The state-of-the-art procedure for examining the lymph nodes in a lung cancer patient involves using an endobronchial ultrasound (EBUS) bronchoscope. The EBUS bronchoscope integrates two modalities into one device: (1) videobronchoscopy, which gives video images of the airway walls; and (2) convex-probe EBUS, which gives 2D fan-shaped views of extraluminal structures situated outside the airways. During the procedure, the physician first employs videobronchoscopy to navigate the device through the airways. Next, upon reaching a given node’s approximate vicinity, the physician probes the airway walls using EBUS to localize the node. Due to the fact that lymph nodes lie beyond the airways, EBUS is essential for confirming a node’s location. Unfortunately, it is well-documented that EBUS is difficult to use. In addition, while new image-guided bronchoscopy systems provide effective guidance for videobronchoscopic navigation, they offer no assistance for guiding EBUS localization. We propose a method for registering a patient’s chest CT scan to live surgical EBUS views, thereby facilitating accurate image-guided EBUS bronchoscopy. The method entails an optimization process that registers CT-based virtual EBUS views to live EBUS probe views. Results using lung cancer patient data show that the method correctly registered 28/28 (100%) lymph nodes scanned by EBUS, with a mean registration time of 3.4 s. In addition, the mean position and direction errors of registered sites were 2.2 mm and 11.8 The state-of-the-art procedure for examining the lymph nodes in lung-cancer patients draws on an endobronchial ultrasound (EBUS) bronchoscope ,2,3,4. TBefore the procedure, the physician first examines a patient’s 3D chest computed tomography (CT) scan to select suspicious lymph nodes a. Later,Unfortunately, EBUS can be difficult to use effectively . This siRecently proposed image-guided bronchoscopy systems have proven to make videobronchoscopic navigation through the airways a high-success, skill-independent operation ,10. UsinThese systems, however, do not offer any means to guide the placement of the EBUS probe for localizing extraluminal sites, as suggested by Several recent works have attempted to extend image guidance to EBUS localization ,21,22,23The other works applied virtual bronchoscopy to the allied problem of peripheral nodule diagnosis ,23. The cenario) . This recenario) . The metOur proposed registration method draws upon the concept of a CT-based virtual EBUS, as introduced by Zang et al. ,26. The The method, partially motivated by previous research in ultrasound registration, draws upon the idea of mutual information (MI). MI techniques have been commonly used to register ultrasound and CT images since the MI metric does not require the two sources to have similar image appearances ,28. FiguDuring live EBUS localization, our proposed method uses an optimization process, which combines both NMI and region shape information, to register CT-based virtual EBUS views to the live views generated by the real EBUS probe. We also integrated the method into an image-guided EBUS bronchoscopy system that features a multimodal virtual EBUS bronchoscope, which integrates both the standard virtual videobronchoscope and the virtual EBUS . Thus, iWe first overview the protocol employed by our image-guided EBUS bronchoscopy system . SectionTo begin, the system complied with the standard protocol of nodal staging bronchoscopy. First, prior to the procedure, a guidance plan was derived from the patient’s high-resolution 3D chest CT scan —this syt et al. .Proper localization of a lymph node depends on our proposed method for registering the virtual and real EBUS probes. To this point, registration involves aligning the virtual EBUS view derived from the preoperative CT scan and the live “real” intraoperative EBUS probe view.p within the 3D virtual space, wherep specifies the location p in , the phe, wherep=a,b,c,tTo formulate the optimization, we employed a cost function y et al. , is giveo images ,41, is gIn , h(ICTp)sume. In , RCTp reperation . Thus, tAlgorithm 1: Multimodal CT-EBUS Registration Algorithm.1.Initialize optimization  with cap2.Segment ROI g et al. .3.Derive a modified pose 4.T iterations.Using cost function ined by (–6)) and) andC), ou), ou6)),po=argminm cost C . To thisAt the conclusion of the registration algorithm, we now know the precise location in 3D chest space of the lymph node depicted in the live intraoperative EBUS probe view Regarding steps 1–2, Step 3 next generates a simplex l voxels . Next, t1.Compute dot product 2.If 3.Otherwise, To find the surface points defining the simplex, we used the algorithm of Gibbs et al. . The sea 1 layer . However 1 layer . Thus, tl. noted . To ensuThe six adjusted vertices T iterations. Steps 3–4 of the top-level multimodal CT-EBUS registration algorithm were then repeated until the voxel corresponding to Step 4 now applies the iterative simplex algorithm to collapse the simplex around an optimal pose po ,44. DuriThe marginal densities  used by CN in (–3)) wer) werCN iFor the station 10 node example of We ran all experiments on the guidance computer. For our tests, this computer was a Dell Precision T5500 64-bit Windows-based PC  powered by an Nvidia Quadro 4000 2GB PCIe graphics engine and a Matrox Vio IA/OA frame grabber. All software was implemented in C++. Many data-intensive operations were parallelized using Nvidia’s compute-unified device-architecture (CUDA) tools and OpenMP. A 24-inch Dell monitor served as the guidance system’s display. A standard Olympus Evis Exera III bronchoscopy suite was used for all tests . To interface the EBUS bronchoscope to the guidance computer, we connected a BNC-to-BNC cable from the bronchoscope display monitor’s PnP (picture-in-picture) video output to the guidance computer’s Matrox video input. This gave access to the live video streams from the EBUS bronchoscope (both the bronchoscopic video and EBUS).We developed and tested our method using data collected retrospectively from 10 lung-cancer patients. These data were collected at our University’s lung cancer management clinic through two IRB-approved study protocols under informed consent. Chest CT scans were generated by Siemens CT scanners. Each scan was made up of 512 × 512 axial-plane sections (number of sections per scan: 570 to 720), with section thickness = 0.75 mm, section spacing To define the ground truth for each ROI, we first picked a 2D EBUS frame I in IUS . Finallyal space . We then1.Position difference 2.Direction error 3.Needle difference To perform the test for each ROI, we began by running the registration method at initial pose ested in :1.PositiRegarding these metrics, For the 28-ROI test set, the registration method correctly localized 28/28 ROIs (100%), with average registration time = 3.4 s, which represents the time to complete the iterative simplex optimization algorithm for  after se1.Positional parameters 2.Angle parameters 3.T from 5 to 25, step size 5.Iteration parameter We next performed a parameter sensitivity test for the registration method. For the test, we first randomly picked one ROI from each human case used in the 28-ROI study. We then performed tests on these 10 ROIs, whereby one search parameter was varied over a given range:(The angle range accounts for the physician’s limitations in twisting the bronchoscope ). For eaT beyond five iterations does result in performance improvement. This gain was less significant, however, from 15 to 25 iterations, especially considering that the mean execution time increased from 3.4 to 8.0 s. Hence, for the previous 28-ROI study and all later human studies, we chose Overall, the initial condition step sizes, which affect the size of the initial simplex, had a minimal impact on the performance. The bronchoscope position and needle errors, Regarding the 28-ROI test, the precise mean registration time = 3.4 s ± 1.6 s, with a range = . Notably, the registration time does depend somewhat on the size of the node. We note that the two largest nodes considered required the longest registration times: (1) 10.0 s for a station 7 node with all axes The registration method has been integrated into a complete image-guided EBUS bronchoscopy system, as described more fully in . Figure Lung cancer persists as the most common type of cancer death, with a mortality rate >85% . The staWe proposed a near real-time CT-EBUS registration method that facilitates an accurate EBUS-based examination of a lymph node during an EBUS bronchoscopy. In particular, after the physician navigates the bronchoscope near the lymph node’s vicinity, the method enables accurate image-guided EBUS probe placement; i.e., the physician can immediately localize the lymph node without the uncertainty encountered in standard EBUS usage. Laboratory results using data from lung cancer patients show the registration method’s robust performance.The method has also been integrated into a complete image-guided EBUS bronchoscopy system designed for chest nodal staging, as demonstrated with system examples. A companion paper by Zang et al. gives more detail related to the system’s guidance and display capabilities . As discWhile these results point to the potential practicality of the method for live clinical practice, a larger multi-center study is needed to more fully ascertain our methodology’s utility for enabling more efficacious EBUS-based nodal staging. One notable limitation is the need to segment ROIs live in the captured real EBUS frame. Some ROIs required multiple segmentation attempts. However, the prospective study gave an acceptable 18.1 s mean time to segment an ROI in a real EBUS frame (part of the 87.4 s mean procedure time per node). Finally, the system requires integration into an approved system meeting federal FDA quality standards.As an additional point, for all lymph nodes considered in our studies, the physician specified the nodal station labels while selecting target lymph nodes on CT during procedure planning. Hence, during the later image-guided EBUS bronchoscopy procedure, when a node scanned by the “real” EBUS is registered to the target CT-based node, this not only confirms the 3D physical location of the node, but it also implicitly confirms the real node’s station label. While not a part of this paper, we had devised a methodology previously for automatically defining the nodal stations and assigning station labels to lymph nodes identified in CT; e.g., ,50.On another note, we also easily adapted the registration method to the newer Olympus BF-UC190F EBUS bronchoscope by a simple adjustment of scope tip specifications . By maki


Residency and fellowship program directors profoundly impact trainees, institutions, and patient safety. Yet, there is concern for rapid attrition in the role. The average program director tenure is only 4-7 years, and that timeline is likely a result of burnout or opportunities for career advancement. Program director transitions must be carefully executed to ensure minimal disruption to the program. Transitions benefit from clear communication with trainees and other stakeholders, well-planned successions or searches for a replacement, and clearly delineated expectations and responsibilities of the outgoing program director. In this Practical Tips, four former residency program directors offer a roadmap for a successful program director transition, with specific recommendations to guide critical decisions and steps in the process. Themes emphasized include readiness for a transition, communication strategies, alignment of program mission and search efforts, and anticipatory support to ensure the success of the new director. In 2022, 6,087 residency and fellowship programs participated in the U.S. National Residency Matching Program . By exteStudies suggest that the average program director tenure is only 4–7 years . While tIrrespective of cause, program director transitions occur in one of two ways. While some may happen abruptly and out of immediate necessity, most transitions can be carefully planned to ensure the least disruptive change for stakeholders and the program-at-large. Planned or not, we believe there are general principles that should be followed when a program director steps down. These reflect the need for thoughtful communication to staff and trainees, searches or successions that strategically align with program missions, and a shared understanding of the involvement of the outgoing program director. If a deliberate approach to this process is not followed, programs risk threats to stability, stakeholder cohesion, progress with ongoing initiatives, and quality of training.In this Practical Tips, we provide program directors a roadmap and best practices for stepping down from the role. Our author team is composed of four former residency program directors with a combined 33 years of tenure, and our collective experiences of stepping down informed the recommendations that follow. We address program directors directly in this piece, although we believe that other education leaders will find the content valuable, as well.Recognize when it is time to step down. There are many reasons that a program director may consider stepping down. Promotion to a new role is common, such as chair/vice chair or assistant/associate dean  Committee, the ACGME, and the human resources office  I liked the practical tip approach and thought the manuscript was well written. I find the content and advice accurate, appropriate and meaningful for both program directors and departments. I have a few edits or comments that if addressed, I think would make the article more appropriate and valuable to its intended audience. Thank you for the opportunity to participate in this review.If evidence from practice is presented, are all the underlying source data available to ensure full reproducibility?Not applicableIs the topic of the practical tips discussed accurately in the context of the current literatureYesAre all factual statements correct and adequately supported by citations?YesAre the conclusions drawn balanced and justified on the basis of the presented arguments?YesAre arguments sufficiently supported by evidence from the published literature and/or the authors’ practice?YesReviewer Expertise:Leadership, medical education and clinical policiesI confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. Overall, I perceive this article as very well done and reflective of the current literature regarding the program director role, responsibilities, as well as factors related to burnout and turnover, hinging on the experiences of 4 well known authors and role models in emergency medicine--which supports the credibility of the contents. It does a nice job suggesting why there is a need to navigate a PD change to begin with, with most common reasons that PD's leave their PD roles due to 1. exhaustion and burnout in the current position or 2. being promoted up and out of the role. It then goes on to fairly clearly outline every step in the process, with each step seemingly generalizable enough that they could be applicable to PD's transitioning roles, regardless of institution. interim PD while the more formal search is being conducted? Or is it supposed to be understood that that is the suggestion here, even without it being fully spelled out? Perhaps just clarifying the role of the PD successor appointed well in advance of the PD leaving the role, and how they serve in the role until a potentially new person is appointed may clear that point up a bit for the readers. To me, if you appoint a PD successor, you are choosing someone internally who will be mentored to take the role. If then an extensive search is conducted, this sort of defeats the purpose of appointing a successor ahead of time and training them up, outside of them being strictly placed as a PD interim in the case of sudden PD loss.  One small thing I was thinking as I read through the points was that point #2, have a succession plan in place, suggests that every PD should have a "go to" person to start fulfilling the role if and when they want to step down--as if this person will be given the PD role when it's time for the transition without any additional questions being asked--sort of an "assumed position". Then when we move to tip 9, we talk about conducting an extensive search looking at both internal and external candidates for the role, treating both equally, and really looking for the person that fits the role the best. So my thought would be how do these points correlate? If you suggest that there should be an automatic PD successor ready, would this person be initially just referred to as Otherwise, no major suggestions, and I really enjoyed reading the article!If evidence from practice is presented, are all the underlying source data available to ensure full reproducibility?YesIs the topic of the practical tips discussed accurately in the context of the current literatureYesAre all factual statements correct and adequately supported by citations?YesAre the conclusions drawn balanced and justified on the basis of the presented arguments?YesAre arguments sufficiently supported by evidence from the published literature and/or the authors’ practice?YesReviewer Expertise:medical education, pass/fail step 1, rural emergency medicine, lower 1/3 SLOEI confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.


In this study, we established α-Syn RT-QuIC using recombinant human α-Syn as the substrate. All 5 brain homogenates of neuropathological PD cases and 13 skin homogenates of clinical PD cases showed positive results, whereas all the samples of negative controls remain negative. Meantime, randomly selected 6 skin samples of PD cases and 6 skin samples of sCJD cases showed negative in opposite prion RT-QuIC and α-Syn RT-QuIC. Our α-Syn RT-QuIC showed dose-dependent manner between the lag times and peak ThT fluorescent values. Additionally, the detecting limitation was about 10–7 dilution for brain tissues and 10–6 for skins. Those data indicate a reliable specificity and good sensitivity of the established α-Syn RT-QuIC in identifying and amplifying the misfolded α-Syn in brain and skin tissues of patients with PD.The real-time quaking-induced conversion (RT-QuIC) assay has been developed and used as an  Chronic neurodegenerative diseases are a group of neurological diseases due to loss of neurons and/or their myelin sheaths, usually affecting elder people with long clinical course but irreversible disease progression. Neurodegenerative diseases include Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington disease (HD), amyotrophic lateral sclerosis (ALS), and prion disease (PrD), etc. Although the etiologies of various neurodegenerative diseases are different, aggregates of amyloidogenic proteins in the lesions of central nerve system (CNS) are the common neuropathological features, which are considered as the valuable disease-specific diagnostic biomarkers .Sc in PrD, undergoing prion-like pathology , and other genetic prion diseases. The reactivities of skin samples of patients with PD and sCJD were also cross-evaluated with opposite prion RT-QuIC and α-Syn RT-QuIC. Our results reveal reliable specificity and good sensitivity of the α-Syn RT-QuIC in distinguishing patients with PD and sCJD experimentally.The post-mortem brain samples from the 4 patients of neuropathologically confirmed PD and one of the patients had corresponding skin samples were kindly supplied by the National Prion Disease Pathology Surveillance Center (NPDPSC), Case Western Reserve University School of Medicine, Cleveland, OH, United States. The skin biopsy samples from 12 Chinese patients with PD were obtained from the Department of Neurology, The First Affinitive Hospital, Guizhou Medical University. A number of one post-mortem brain sample and the biopsy skin sample from a patient with neuropathologically confirmed PD were obtained from the Department of Neurology, Beijing Tiantan Hospital, Capital Medical University. Some clinical information of the enrolled patients with PD is shown in g for 10 min, the supernatants were collected and stored at –80°C for further usages.Brain homogenates  were prepared by homogenizing the cortical brain tissues in lysis buffer  with 0.5 mm zirconium oxide beads with shaking for 1 min at maximum speed. According to the previously described protocols , roughlyPrion RT-QuIC assays were conducted as described previously . α-Syn RThe lag times and the peak fluorescence values were analyzed and plotted by the software GraphPad Prism.–2, 10–3, and 10–4 diluted preparations of each sample were prepared, respectively. All 5 samples from PD cases were positive in α-Syn RT-QuIC , and 1 G114V genetic CJD (gCJD), were recruited into this study. After prepared brain homogenates, 10 RT-QuIC . Furtherdilution . Contrardilution . Notably–3, 10–4, and 10–5 diluted skin homogenates were separately prepared. Positive α-Syn RT-QuIC was considered in all skin samples of 13 PD cases  was negative in 10–3 but positive in 10–4 and 10–5. Repeat α-Syn RT-QuIC tests of these three cases illustrated the same results  of α-Syn RT-QuIC for α-synucleinopathy have been reported in some previous studies with relatively large case numbers . High acSome studies of skin prion RT-QuIC have revealed a variation in seeding activity based on the sampling sites. The skin specimens from ears and back of prion infected experimental rodents showed slightly higher seeding activities than that from limbs . The ski50/mg: 5 × 104) in α-Syn RT-QuIC is lower than that of brains (SD50/mg: 2.8 × 106)  in US after undergone a complicate approach of enrichment  . Howeverof skins . Study of brains . Our stuactivity , 2021. Urichment . Such di–5) skin samples of PD cases seem to induce more positive reactions in α-Syn RT-QuIC than lower diluted (10–3 and 10–4) ones. Higher concentration of samples but lower capacity in the aggregation of α-Syn may reflect that some unidentified components in the tested samples are not conducive to the nucleation and growth of α-Syn aggregates (–4 and 10–5) with 3–4 duplicating wells and the reaction time of 120 h for future application. The diagnostic significance of the established α-Syn RT-QuIC of biopsy skin specimens for Chinese patients of α-synucleinopathy still needs large-scale clinical trials.Under our experimental condition, higher diluted  of the University Hospital Cleveland Medical Center Written informed consent was obtained from family members for skin autopsy through the NPDPSC. The patients/participants provided their written informed consent to participate in this study.D-DC contributed to study design, performed the experiments, and prepared the manuscript. LJ and YH assisted with collecting and organizing clinical cases. KX, L-PG, and CC assisted with the preparation of experimental materials and statistical analysis. QS contributed to the study design and collect clinical cases. X-PD and QS contributed to the design, study concept, and final manuscript preparation. All authors read and approved the final manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


We aimed to develop a horticultural therapy program to prepare adolescents at the Dae san juvenile detention center (D-JDC) for their return to society. The effects of the program on emotional stability and career exploration were investigated. Adolescents who wished to participate in the horticultural therapy program were recruited from the D-JDC. Data were collected using various questionnaires before and after the program was implemented. Thirty-five  students were enrolled. The program mainly consisted of plant cultivation activities, such as seeding, transplanting plants, cutting, harvesting, and post-harvest utilization. To evaluate emotional health, the ego-resiliency scale was used. To evaluate social behavior, the inventory of parent and peer attachment, peer attachment scale, and social skills scale were used. Career exploration was assessed using the career preparation behavior scale and the career decision-making self-efficacy-short form. Peer attachment, social skills, and career preparation behavior showed significant improvements after the program, with the students responding positively in the post-program surveys. Our horticultural therapy program helped improve the career exploration and social skills of D-JDC students and positively affected their emotional stability. Based on our findings, horticultural therapy can be used as a correctional program for adolescents in D-JDC to help them return to society. Adolescence is a transitional period from childhood to adulthood, during which an individual undergoes drastic physical, psychological, and social changes ,2. In paDepending on the educational background, age, and admission time of JDC students, they are provided specific educational programs, career development training, personality education courses, and general education. Furthermore, Dae san JDC (D-JDC) provides medical care and rehabilitation education to protected young people. Personality development education, which has been designed for the reformation of prisoners in South Korea, is mainly aimed at influencing psycho-emotional aspects such as self-esteem, return to society, mental health, and interpersonal relationships. Research trends by subject are in the order of horticultural therapy 25%), art therapy (20%), and music therapy (17.5%) . In addi%, art thHorticultural therapy is a professional client-centric treatment that utilizes aspects of horticulture to meet the specific therapeutic or rehabilitative needs of participants; it was first introduced in South Korea in the 1980s and has become increasingly popular since . The morThe present study determined the efficacy of a horticultural therapy program, based on the precepts of the TOP, that was designed to improve the emotional health and career exploration skills of adolescents at the D-JDC. The program utilized native plants to improve the self-efficacy, peer attachment, social skills, career preparation skills, and self-efficacy in career decision making among the juveniles at the JDC.We designed a horticultural therapy program with the help of an education officer at the D-JDC located in Daejeon city. We recruited male and female students who volunteered to participate. Before starting the study, the purpose of the study and precautions regarding horticultural therapy were explained, and informed consent was obtained from the volunteers. Thirty-five students completed the eight-session program, with an attendance rate of 91.4%. Owing to the nature of the JDC, which mainly provides psychological rehabilitation and treatment, the participants often missed sessions since they experienced frequent psychological changes, had to attend psychological counseling, or were released. The present study was approved by the Institutional Bioresearch Ethics Committee of Konkuk University (7001355-2018-HR-275).Spiraea salicifolia L., Hydrangea serrata f. acuminata (Siebold & Zucc.) Wilson, Caryopteris incana (Thunb. ex Houtt.), Allium senescens L., Iris ensata ‘spontanea’ (Makino) Nakai, Aster koraiensis Nakai, Lythrum salicaria L., Dendranthema indicum (L.) Des Moul., Pteridium aquilinum (L.) Kuhn, Mentha arvensis ‘piperascens’ L., and Prunella vulgaris var. lilacina were used in various activities, such as seeding, transplanting plants, cutting, harvesting, decorating pressed flowers, and still life drawing , developed by Block and Kremen , was useFor evaluating social behavior, the Inventory of Parent and Peer Attachment (IPPA), developed by Armsden and Greenberg , was useWe used the career decision-making self-efficacy: short form (CDMSE-SF) developed by Lea and Lee . The CDMp < 0.05.For demographic data analysis, descriptive statistics were calculated  using Microsoft Excel . To analyze the effects of the horticultural therapy program, the distribution normality was tested using SPSS , and the data were analyzed using paired t-tests, with the significance level set at The respondents were aged between 10 and 19 years ; 11 male and 24 female students were included. Regarding educational background, 97.1% had a middle school diploma or lower, 88.6% of them were students at the time of the survey, and 54.36% lived in the metropolitan area .p = 0.365). Among the sub-items, vitality, interpersonal relationships, emotional control, curiosity, and optimism showed prominent changes.p = 0.05). Social skill scores also showed a significant improvement from the pre-score of 17.66 (15.30) to the post-score of 27.91 (15.03) (p < 0.001).p < 0.05). The CDMSE-SF score significantly improved from the pre-score of 80.69 (21.04) to the post-score of 86.09 (20.57) (p = 0.113).Among the youths who participated in this study, 88% stated that they were generally satisfied with the program; furthermore, 94% stated that they were satisfied with the total number of sessions in the program (eight), and 6% stated that they were not satisfied. Regarding the number of sessions, the following responses were collected: 100 session (one youth), 12 (two youths), 10 (two youths), 3 (three youths), and 2 (one youths). Of the respondents, 74% (23 persons) stated that they were satisfied with the 90-min session duration; others preferred session durations of 10, 30, 60, 100, and 120 min. Regarding the frequency of once a week, 71% were satisfied and 10% were dissatisfied; 50% of those who were not satisfied wanted the program to run twice a week. The most preferred activity was cutting (16%) followed by flower decoration (15%), urban agriculture manager job experience (14%), planting (13%), welfare gardener job experience (13%), seed sowing (12%), harvesting (11%), and transplanting (6%). Further, 45% stated that it was good to learn new things and that the therapy enhanced their job search skills (76%). The respondents were open to participating in horticultural therapies in the future and were willing to recommend the therapy to their friends. They stated that the program was fun and friendly.The eight-session horticultural therapy program had a significant effect on the development of the peer attachment, social skills, and career preparation behaviors of the adolescents at the D-JDC. The adolescents reported a significant increase in peer attachment after the horticultural therapy program. This result was consistent with those of previous studies, where indoor horticultural therapy with easy access improved peer relationships through plant care and group activities and that horticultural activities had a positive effect on peer relationships ,36. AlthRegarding social skills, the teachers noticed a synergistic effect of the therapy. The adolescents performed well in cooperative functions such as helping others, sharing objects, and following rules or instructions for using living plants. It is believed that positive effects were achieved by making self-assertions, accepting suggestions from friends, and exercising self-control in a conflict situation. These results were consistent with those of previous studies, where increased social relations were reported among children who engaged in horticultural therapy ,38,39.Career preparation behavior showed a significant improvement, consistent with the results of a previous study that reported on the ego-resiliency and social support of out-of-school adolescents . GinzberThe students who completed the horticultural therapy program showed improved self-resilience and career decision self-efficacy and developed skills to cope well with internal and external stressors. The sub-items of ego-resiliency, interpersonality, emotional control, curiosity, optimism, and vitality showed significant improvements. The expectations and curiosity about new plants and activities observed in each session appear to support the problem-solving ability of the participants. This result is in line with those of a previous study where attachment to plants and curiosity in a cultivation-based horticultural therapy program were found to be effective in improving the psychological health of adult prisoners ; in anotThe program had a positive effect on self-efficacy in career decision-making, which indicates that experiencing and understanding plants and plant cultivation firsthand enabled the participants to accomplish the horticultural-related career activities, which in turn increased their confidence in their ability to make careful and wise decisions. Considering that juvenile offenders have to leave the regular school system and receive correctional education at the JDCs, the educational function of the JDCs should be developed. Instead of solely pursuing responsibility for misconduct among the juvenile offenders, the state, as the new guardian, should also focus on character development, specialized education, and career development training to help them gain the knowledge and skills necessary for their social roles after release ,46.The present study verified that the emotional stability and social adaptability of the juveniles at the D-JDC changed positively through the implementation of a horticultural therapy that focused on career exploration for adolescents with uncertain career paths. Furthermore, the program was effective in improving the participants’ career design ability. This study is limited to certain region participants, and it is difficult to generalize the results due to the absence of a control group. Future studies should focus on further understanding the role of native plants in supplementary career-based education for juveniles. The horticultural therapy program developed in this study is expected to be an excellent educational program for improving career preparation among young people in correctional institutions.


Stingless bees, also known as meliponines, live in beehives. However, reports on the distribution of stingless bees are scattered, resulting in a lack of precision. Honey and propolis are the main components that can be harvested from their beehive, with a great commercial value of up to 610 million USD. Despite the enormous potential profits, discrepancies in their bioactivities have been observed worldwide, leading to a lack of confidence. Therefore, this review provided oversight on the potential of stingless bee products and highlighted the differences between stingless bees in Asia, Australia, Africa, and America. The bioactivity of stingless bee products is diverse and exhibits great potential as an antimicrobial agent or in various diseases such as diabetes, cardiovascular disease, cancers, and oral problems. Hymenoptera, Apidae: Meliponini), comprising 60 different groups divided into 600 different species and subspecies [Apini relatives, especially Apis mellifera) [The tropics and subtropics are home to thousands of unique bee species. Meliponini, also known as stingless bees, is one of the species that captured the attention of researchers . Stinglebspecies . The colllifera) . The higA. mellifera propolis was estimated to constitute the vast bulk of the market for propolis [Stingless bee products such as propolis and honey bring high commercial value. For example, it was estimated that the global commercial market for propolis was worth approximately 610 million USD in 2020, with an estimated annual net growth rate of 5.48% from 2021 until 2026 [Hymenoptera, Apidae: Meliponini) has been employed in traditional medicine in Peru for at least a few centuries. This honey is collected by felling trees that contain bee colonies, locating the honey pots, and then leaving the nests exposed rather than harvesting them for meliponiculture. Additionally, colonies are commonly found in the walls of homes and other manufactured constructions [Honey produced by stingless bees  are very different [H. Itama propolis being more effective than G. thoracica. It was reported that the higher phenolic concentration of H. Itama propolis was responsible for its antibacterial activity [H. Itama bees had anti-inflammatory and antioxidant properties [H. Itama in Malaysia has great beneficial effects.The chemical contents of the two species . α-MG is a plant-derived compound with multiple pharmaceutical properties, including antibacterial ones [S. aureus (MRSA), and Gram-positive pathogens do not develop resistance against α-MG [Additionally, there have been reports of biological activity in a few different preparations of Thai stingless bee propolis described as follows. The Thai stingless bee compound . Howeverial ones , 23. α-Mnst α-MG , 25.T. laeviceps and T. melanoleuca, were tested for their ability to inhibit the growth of the pathogen Cryptococcus neoformans [C. neoformans from producing chitin and chitosan, both components of the cell wall, as well as melanin, which is a virulence factor [CDA1, IPC1-PKC1, and LAC1 that are implicated in the cryptococcal melanization pathway was reduced by propolis treatment [Propolis from two different species of stingless bees, oformans . Propolie factor . Additioreatment . The proreatment –33.T. carbonaria were reported to exhibit anti-inflammatory activities. The most frequent compounds, according to the gas chromatographic data, were a combination of phenolics and terpenoids, notably pimaric acid, isopimaric acid, and gallic acid [In Australia, little research has been done on the bioactive compounds of propolis produced by stingless bees. Despite this, studies have revealed that the propolis produced by Australian stingless bees has therapeutic properties . For exalic acid .S. aureus and was thought to be responsible for therapeutic advantages [M. ferruginae) [Dactylurina Staudinger exhibits antibacterial activity for Gram-positive and Gram-negative bacteria infections [Propolis was reported to have a dose-dependent relaxing effect on the arteries of smooth muscles. Propolis extract of stingless bees also showed antibacterial action against vantages . Consequruginae) . Additiofections . DespiteCandida species [There is a strong argument that Brazil has conducted the most comprehensive research on the biological activity of stingless bees' antibacterial, anti-inflammatory, and antioxidant biological properties. These arguments were consistent with Asian-origin stingless bees and stingless bee propolis of Australian origin . Propoli species .Scaptotrigona aff. postica and M. subnitida. The antioxidant activity had several properties, such as radical scavenging, reducing power, and metal-chelating abilities [Scaptotrigona aff. postica propolis extract had antagonistic effects on asthma [M. subnitida improved healing lesions' evolution, boosted angiogenesis and collagen synthesis, and decreased inflammatory cell recruitment [M. subnitida is one of the major potential products to be utilized in future treatments.American stingless bees propolis contain antioxidant activities, and these properties were observed in different bee species such as bilities . Propolibilities . Propolibilities . The antn asthma . Propoliruitment , 44–53. ruitment –56. ThisApis mellifera remain a challenge because of the rising threat of various diseases and the increased use of agrochemicals to combat foreign bodies [th century [A. m. scutellata cause the spread of Africanized population, which affects the A. mellifera European lineages [Apiculture or beekeeping using n bodies . Melipon century , 59. EveSince the beginning of recorded history, propolis has been utilized as a medicinal ingredient. Propolis is made of a resinous material that can be obtained from many different plants. Propolis has been used to construct hives and protect their colonies. In addition, the propolis produced by stingless bees is referred to as geopropolis because it is produced from plant resins mixed with pollen, wax, salivary secretions, and soil. However, the name "geopropolis" is sometimes used to refer to propolis collected by Meliponini in general, which is not accurate because only some species of Meliponini add soil and clay to the plant resins collected in their nests .AmEater gene expression are repressed by propolis [Propolis has a high level of biological activity and is associated with a wide variety of beneficial effects on human health, including antiviral, antibacterial, antifungal, anticancer, immunomodulatory, and anti-inflammatory . There ipropolis , 64. Thein vitro to human clinical trials that are randomized, controlled, and monitored with placebos [Humans have utilized propolis for around the same amount of time as honey. Surprisingly, the medical application of propolis developed independently throughout millennia in a variety of different ancient communities. According to historical texts, propolis was utilized by ancient peoples in Egypt, Greece, Persia, and Rome to treat a wide variety of illnesses and conditions. It is reported that Hippocrates employed propolis to treat ulcers as well as internal and external wounds of the body. Propolis has been used as a form of traditional medicine for a very long time in India as ayurvedic medicine. The efficacy of propolis as a therapeutic agent has been demonstrated unequivocally and comprehensively by recent studies . Evidencplacebos . Diabeteplacebos –69.In every wound, there is a population of microorganisms; nevertheless, the vast majority of these organisms do not cause an infection, and the wound eventually heals. However, under certain conditions, the wound can be severely infected. This is due to the weakened immune system that leads to the multiplication of pathogens and transmission of the infection to the host's tissues, which may result in granuloma or an abscess . If thisBacillus genus, Actinomycete, or Streptomyces, which do not obstruct the body's natural healing process.As reviewed earlier, honey or cerumen contains a large number of microorganisms. When honey is applied to a wound, the effect that this may have on the body's natural ability to heal is a topic of discussion . Most ofThe prevention or treatment of infections, particularly when the patient is healing, is the major objective of antimicrobial treatments. Honey produced by stingless bees can be utilized in pharmaceutical preparations as an antibacterial component because it possesses antimicrobial and antiseptic properties .A. mellifera, but Emi et al. discovered it in a variety of honey samples produced by stingless bees from different parts of the world [et al. conducted an entomological study and found that the cuticular antimicrobial compounds emitted by stingless bee honey were also responsible for inhibiting microbial growth [Components containing peroxide and those that do not contain peroxide are responsible for the antibacterial action of honey. The activity of hydrogen peroxide provides the foundation for the peroxide component, controlled by glucose oxidase and catalase, both necessary enzymes in the honey. Catalase neutralizes the hydrogen peroxide produced by glucose oxidase, which allows the honey's nutritional content to be preserved. Glucose oxidase stimulates the production of hydrogen peroxide. Hydrogen peroxide increases cytokine production, which plays a role in the inflammatory response against germs . The anthe world . Stow etl growth . Honey pl growth .Trigona, the researchers found that the hive consists of 63.7 percent propolis, 20.9 percent beebread, and 15.4 percent honey [The percentages of stingless bee-based elements in the beehive are currently unknown, although these percentages fluctuate based on the bee species. Because the hive itself is constructed out of propolis, the majority of a hive inhabited by stingless bees will contain propolis as its primary component. In a study that looked at nine different species of nt honey , 78. In Saccharomyces cerevisiae, Acetobacter spp., or Pediococcus spp. [Stingless bees are responsible for the production of honey, which is then stored in the hive in tiny resin pots. In earlier times, honey would typically be extracted from honey pots by pressing them. This approach had several downsides, such as causing pot damage and reducing the number of bees produced. When the pot honey was squeezed, it produced stingless bee honey contaminated with bee bread containing microorganisms. This stimulated the honey to ferment, which produced a variety of honey products such as honey wine and honey vinegar by several microorganisms such as cus spp. –81. TherThe chemical makeup of goods derived from stingless bees differs depending on their botanical and geographical origin, the species of bees used, and the local climate. This is true even when harvesting methods and post-harvest management of stingless bee honey have been improved. Hence, there is currently no internationally accepted characterization standard for stingless bee products , 82.This review article shows that stingless bee products have the potential to act as antimicrobial agents in the future. The present article observed that different regions of the world have different predominant species of bees. However, it is important to note that regions with long winters have a low colony of stingless bees that resulted in being understudied. Biological activities remained one of the most important aspects in the sting and stingless bees' studies and were found to regulate several different cellular pathways. Hence, future studies are critical in promoting and understanding the mechanism of action of sting and stingless bees to act as antimicrobial agents or other potential biological activities.


Rural caregivers are often underserved by caregiving services, yet little is known about how the intersectionality of geographic context and race/ethnicity relates to caregiving resources among dementia caregivers. We examined whether 1) caregiving resources and experiences differ across metro and non-metro areas; and 2) the use of caregiving resources is associated with geographic context by race/ethnicity, controlling for age, gender, and education. We analyzed a sample of caregivers of care recipients aged 65 years or older with ‘probable’ dementia (n= 808) in the 2017 National Health and Aging Trends Study (NHATS) and the associated National Study of Caregiving (NSOC). We defined geographic context by the recipient’s residence in metro (urban) or non-metro  counties and grouped formal  and informal (family or friend help) resources. Among minority caregivers, 47% of those living in metro and 36% in non-metro areas used a formal service, and 83% and 72%, respectively, used informal resources. Among White caregivers, estimates were 44%, 48%, 76%, and 66%, respectively. Multivariate regression analyses revealed that non-metro White dementia caregivers had 2.04 times higher odds (95% CI=1.10-3.78) of using formal resources than metro White dementia caregivers. This pattern was not observed among minority dementia caregivers. The use of informal resources did not differ across geographic contexts by race/ethnicity. Findings suggest the influence of geographic context on the use of formal caregiving resources varies by race/ethnicity. With higher rates of dementia in non-metro areas, formal caregiving resources among non-metro minority dementia caregivers need more attention.


In the absence of randomized controlled trials (RCTs) on the benefits of therapeutic exercise programs involving children with bronchiectasis, we undertook a pilot RCT to evaluate the effects of a play-based therapeutic exercise program on fundamental movement skill (FMS) proficiency. The effects of the program on cardiorespiratory fitness, perceived competence, and health-related quality of life (HR-QoL) were examined as secondary outcomes.n = 11) or wait-list control (n = 10). The exercise program comprised 7 × 60-min weekly sessions and was supplemented by a home-based program 2-days/week. Participants were assessed on: FMS (locomotor and object control skills) using the Test of Gross Motor Development 2nd Edition (TGMD-2); cardiovascular fitness by calculating the percent change in heart rate (%ΔHR) from rest to completion of the first stage of a submaximal treadmill test; perceived competence using Harter’s athletic competence subscale; and QoL with the PedsQL.Children [median (IQR) age: 6.8 (5.3–8.8) years] with bronchiectasis unrelated to cystic fibrosis were randomized to a 7-week therapeutic exercise program (p = 0.01) and object control  skills, with no significant change in controls . Among children completing the program, %ΔHR declined by 6% points, while %ΔHR declined only marginally among controls (0.9% points), but the group by time interaction was not statistically significant. The program had a small positive impact on competence perceptions (Cohen’s d = 0.2) and HR-QoL (Cohen’s d = 0.3).Significant group by time interactions were observed for locomotor and object control skills. Children completing the therapeutic exercise program exhibited significant improvements in both locomotor (pre 29.0 ± 2.0, post 35.2 ± 2.2, This pilot RCT provides preliminary evidence for the efficacy of a play-based therapeutic exercise program to improve proficiency in FMS and fitness in children with bronchiectasis. The results are sufficiently positive to warrant conducting a larger RCT testing the efficacy of the exercise program in children with bronchiectasis and/or other chronic respiratory conditions. Globally bronchiectasis is recognized as a major cause of respiratory morbidity, mortality and health-care utilization . It is pCurrent guidelines for the treatment and management of bronchiectasis call for regular exercise as a means of improving cardiovascular fitness and QoL , 7. HoweChildren meeting the following inclusion criteria were eligible to participate in the study: diagnosed with bronchiectasis, aged between 4 and 13 years, and able to complete an exercise program. Bronchiectasis was diagnosed according to the then current guideline published by the Thoracic Society of Australia and New Zealand (N = 20). This calculation was based on an anticipated between-group difference of at least 0.8 standard deviations (SDs) for locomotor and object control movement skills, respectively , Brisbane, Australia, between March 2015 and February 2017. Clinicians were provided a detailed study description, along with the inclusion and exclusion criteria, and asked to identify children who met the criteria and would benefit from participating in a therapeutic exercise program addressing movement skills and aerobic fitness. Parents of potential participants were subsequently contacted by the primary investigator (BJ) who formally assessed eligibility and provided details about the study. After discussing the study, parents with children who were eligible and interested in participating provided written informed consent. Children aged ≥7 years also provided written assent. Following established procedures for estimating the sample size for a pilot RCT , the minectively . EthicalA single-site, open RCT was conducted in a clinical setting at a public hospital in Brisbane . After providing consent (and/or assent), children completed baseline assessments which were conducted by the primary investigator at the Queensland Centre for Children’s Health Research (CCHR) in Brisbane, Australia. After baseline testing, children were randomized to the therapeutic exercise program or the wait list control condition. A permuted block randomization method was used for allocation, with four children in each block. An external statistician not actively involved in the recruitment or data collection generated the randomization sequence. The allocation sequence was concealed in a set of sealed opaque envelopes labeled with the participant number. Children randomized to the exercise group started the program 1 week after baseline assessments and completed the post-program assessments within 1 week of finishing the last exercise session. The baseline and post-test assessments and delivery of the exercise program was conducted by the principal investigator (BJ); thus, assessor blinding was not possible. Participants also were not blinded to group allocation as this is not possible in an exercise intervention study. Children randomized to the control group received the intervention after completing post-program assessments.The therapeutic exercise program aimed to improve FMS and cardiorespiratory fitness. The program comprised a combination of supervised and unsupervised exercise. The supervised sessions consisted of one 60-min session per week, conducted over 7-weeks, led by a clinical exercise physiologist (BJ). To supplement each supervised session, children completed a home-based program 2 days per week which consisted of two games from their most recent hourly session. During each 60-min session, children rotated through six activity stations where they completed developmentally appropriate games targeting specific FMS. A description of each game is provided in Parents completed a brief questionnaire providing information about their child’s health history, duration of cough, type of cough, current medication, frequency of doctor visits during the last 12 months, and family demographics .Fundamental movement skills were assessed using the Test of Gross Motor Development 2nd Edition (TGMD-2) . The TGMCardiorespiratory fitness was measured using a submaximal graded treadmill test following the Balke protocol for low active children . For ethPerceived competence was assessed using the athletic competence subscale from Harter’s Self-Perception Profile for children . This suThe Pediatric Quality of Life Inventory (PedsQL) 4.0 was utilized to assess QoL . The PedThe parent-proxy cough-specific quality of life (PC-QoL-8)  consistsd was used to describe effect sizes. A Cohen’s d of 0.2 corresponded to a small effect size, 0.5 to a medium effect size and 0.8 to a large effect size  ANOVA was used to assess the effect of the therapeutic movement program on FMS, cardiovascular fitness perceived competence, QoL and PCQOL. Data were analyzed according to the intention to treat principle, with missing values imputed using the last observation being carried forward method . Cohen’sect size . All anaIn total, 21 children were enrolled in the study, with 11 randomized to the exercise group and 10 to the control group. The flow of the participants through the study is shown in Descriptive statistics for the exercise group and control group are reported in F = 7.6, p = 0.01) and object control skills  = 8.3, p = 0.01). Children randomized to the exercise group exhibited statistically significant and substantial improvements in both locomotion and object control movement skills, while the control group exhibited little change. The associated effect sizes indicated that the exercise group had a large positive effect on locomotor and object control skills. No significant group by time interactions were observed for scores on the Harter’s perceived athletic competence scale, PedsQL and PCQoL.F = 0.9, p = 0.4). Expressed as an effect size, the exercise program had a moderate positive effect on cardiorespiratory fitness (Cohen’s d = 0.5).d = 0.5) was commensurate with that reported for improvements in aerobic fitness in asthmatic children completing exercise training  delivered the program and completed the assessments. While assessor bias cannot be ruled out, it is important to note that the assessments of cardiorespiratory fitness, perceived competence and QoL were instrument based and therefore did not require interpretation from the assessor. While locomotion and object control scores were based on assessor ratings, the TGMD-2 assessment protocol mitigates against observer bias by clearly delineating the critical features for each skill, which are coded as being present or absent. Third, the exercise program comprised of seven supervised 60-min weekly sessions, with a supplementary home-based program completed twice a week, which is a relatively low dose for an exercise intervention . Despited = 1.2) and object control skills (Cohen d = 1.3) and an estimated SD of 6.8 for locomotor and object control standard scores (based on the observed SD and the recommended inflation factor of 1.099), a sample size of 24 participants will be required. To offset a projected dropout rate of up to 25%, the larger trial should recruit and enroll 15 participants per group, providing a total trial sample size of N = 30. This calculation assumes a power level of 80% and a two-sided alpha level of 0.05. In addition, a future RCT should consider implementing the program over a longer duration (8–10-weeks) and employ accelerometer-based motion sensors to monitor the supplemental home-based exercise sessions. Where possible, future studies should be carefully designed to minimize bias , and include a follow-up period to determine the extent to which improvements in FMS proficiency are maintained over time and contribute to positive changes in other health outcomes such as physical activity performance, cardiorespiratory fitness, and health-related QoL.In conclusion, this pilot RCT provides preliminary evidence for the efficacy of a seven-session play-based therapeutic movement program to improve proficiency in FMS in children with bronchiectasis. The program had a moderate positive effect on cardiorespiratory fitness, but no improvements were noted for perceived competence and QoL. The results are sufficiently positive to warrant conducting a larger RCT testing the efficacy of the exercise program in children with bronchiectasis and/or other chronic respiratory conditions. Based on the observed effect sizes for the impact of the program on locomotor skills  and the Human Research Ethics Committee at the University of Queensland (2014001176). Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.BJ and SGT designed the study. BJ collected and analyzed the data and wrote the manuscript. SGT was a major contributor in designing the study, analyzing data, and writing the manuscript. SG and ST helped designing the study and writing the manuscript. HP and AC helped with recruiting the participants and writing the manuscript. All authors read and approved the final manuscript.


Plants deploy extracellular and intracellular immune receptors to sense and restrict pathogen attacks. Rapidly evolving pathogen effectors play crucial roles in suppressing plant immunity but are also monitored by intracellular nucleotide-binding, leucine-rich repeat immune receptors (NLRs), leading to effector-triggered immunity (ETI). Here, we review how NLRs recognize effectors with a focus on direct interactions and summarize recent research findings on the signalling functions of NLRs. Coiled-coil (CC)-type NLR proteins execute immune responses by oligomerizing to form membrane-penetrating ion channels after effector recognition. Some CC-NLRs function in sensor–helper networks with the sensor NLR triggering oligomerization of the helper NLR. Toll/interleukin-1 receptor (TIR)-type NLR proteins possess catalytic activities that are activated upon effector recognition-induced oligomerization. Small molecules produced by TIR activity are detected by additional signalling partners of the EDS1 lipase-like family (enhanced disease susceptibility 1), leading to activation of helper NLRs that trigger the defense response. R’ genes  and pathogen Avirulence ‘Avr’ genes (recognized effectors). PTI provides a broad-spectrum resistance to a wide range of nonadapted pathogens and as such contributes to basal immunity [Plants and animals are continuously coresident with microbes, many of which are potential pathogens. While animals deploy specialized mobile cells within a circulatory system as the basis of adaptive immunity, plants rely on a cell-autonomous immune system to detect and restrict pathogen attacks. This comprises two main layers of recognition that operate either at the cell surface or in the host cytoplasm as illustrated in immunity ,10,11. Eimmunity ,13. Therimmunity ,15. In tR-NLRs or RNLs [NLR gene families. However, in other cases, additional noncanonical domains in some NLRs can mediate recognition as described below [NLR proteins occur in plants, animals, and fungi and share a basic protein architecture consisting of a conserved central nucleotide-binding (NB) domain, a C-terminal LRR domain, and distinct N-terminal domains. Plant NLRs can be subdivided into two main groups according to their N-terminal domains: those containing an N-terminal TIR (Toll/interleukin-1 receptor and resistance) domain (TIR-NLR or TNL), and those with an N-terminal CC (coiled-coil) domain (CC-NLR or CNL). A subset of CC-NLRs have CC domains related to RPW8 (resistance to powdery mildew 8) and are known as CC or RNLs ,17. Gene or RNLs . The cen or RNLs . In many or RNLs , and coned below ,26.Recognition of effectors in the intracellular space of host cells is a central event in the activation of ETI. Plant NLR proteins can recognize effectors directly by physical interaction or indirectly through an intermediate partner as illustrated in A number of examples of direct interactions are given in Recent structural determination of the TIR-NLR proteins, ROQ1 and RPP1, in complex with their respective effectors, XopQ1 and ATR1, revealed key insights into the molecular basis of recognition ,26,44. IPseudomonas syringae AvrRps4 and Ralstonia solanacearum PopP2, leading to immune responses mediated by the executor protein RPS4 [in planta, but overexpression of the sensor NLRs, RRS1 and RGA5, does not [NLRs with integrated decoy domains often occur as one member of an NLR pair, in which one protein known as the sensor NLR contains an ID that interacts directly with effectors to induce activation of the alternate executor (or helper) NLR B 17,28,,28,30,47ein RPS4 ,51. Thesein RPS4 . Overexpdoes not ,54. Moredoes not .Several early studies showed that self-association of the TIR or CC signalling domains is a precondition of cell death activity. For example, mutations that disrupt the self-association of Sr33 or MLA10 CC domains abolish the cell death caused by either expression of the CC domain alone or the full-length CNL protein ,56. SimiXanthomonas effector AvrAC indirectly via a decoy protein kinase, PBS1-like protein 2 (PBL2). After uridylation by AvrAC, PBL2UMP interacts with the ZAR1-RKS1 complex through RKS1, causing outwards rotation of the ZAR1 NB domain, which promotes ADP release and subsequent ATP binding. ATP binding induces further structural changes that assist formation of the active pentameric structure. The N-terminal α1 helix of the CC domain is exposed upon ZAR1 activation and in the resistosome complex, the five CC domains form a funnel-shaped structure with the α1 helices at the apex. The active ZAR1 resistosome associates with the PM and can act as a Ca2+ influx channel [2+ permeable channel that is necessary for immunity activation. Newly published research shows that the isolated CC domain of the Arabidopsis helper CCR-NLR NRG1.1 also adopts a four-helical bundle structure that closely resembles those of other plant CC domains and the inactive state of ZAR1 [AtNRG1.1 protein oligomerizes and forms puncta in the PM, and both activated AtNRG1.1 and AtADR1 can cause Ca2+ influx. Both channel activity and cell death induction also require conserved negatively charged residues in the N-terminal of the CC domains, as observed for ZAR1. This suggests that the CCR domains of these proteins function similarly to the CC domains of other CNL proteins. Moreover, transcriptome analysis revealed that similar gene expression changes are triggered by activation of both CCR-NLRs and other CNLs [2+ permeable channels might be a common mechanism for immune activation by CC-NLRs. There are, however, exceptions to this model. For instance, many of the CC-NLRs in the Solanaceae family operate within a sensor-helper network, where a variety of sensor CC-NLRs are involved in pathogen detection but require helper CC-NLRs of the NRC family to induce immune responses [Structural determination of complexes containing the full-length CC-NLR protein ZAR1 revealed major conformational changes during its activation. This work identified three structural phases: an inactive monomeric state, an intermediate preactivation monomeric state, and the active state, which forms a wheel-like pentameric resistosome complex ,61. Inac channel . Mutatio of ZAR1 . Moreoveher CNLs ,65. Hencesponses ,67. For esponses . A recenesponses  suggests+ and generate a variant-cyclic-ADP-ribose products (v-cADPR), which is hypothesized to activate downstream signalling [+ hydrolase activity [albeit at much lower levels than SARM1 [TIR-NLRs adopt a very different signalling strategy compared with CC-NLRs. TIR domains possess NADase catalytic activity; upon self-association, TIRs hydrolyze NADgnalling ,20. The activity ,71. Planan SARM1 ,20. The an SARM1 ,20. ThesNicotiana benthamiana and RPP1 from Arabidopsis recognize their cognate effectors directly [N. benthamiana [The TIR-NLR proteins ROQ1 from directly ,26. Unlithamiana ,72. Thusthamiana . This acthamiana .R-NLRs, NRG1 and ADR1, that work co-operatively with either the EDS1-SAG101 or EDS1-PAD4 heterodimers, respectively, to mediate immunity [Two levels of signalling components are required downstream of the TIR domain catalytic activity  leading to resistance outputs . The firimmunity ,78–82. IEDS1 family proteins feature an N-terminal lipase-like α/β-hydrolase-fold domain and a C-terminal EP domain (named from the EDS1-PAD4 interaction), which is composed primarily of α-helical bundles . Both EDR-NLRs, ADR1 and NRG1, represent an ancient branch of the CC-NLR gene family that occurs in widely diverged plant lineages. This family is usually represented by only one or a few copies within each species in contrast with the broad diversity of other CNL and TNL families. CCR-NLRs from various species, especially Arabidopsis, are required for the function of all tested TNLs and some CNLs [AtADR1s are used by both TNLs and CNLs and function upstream of the SA pathway to restrict pathogen growth, whereas AtNRG1s function mainly for cell death induction by TNLs. AtADR1s and AtNRG1s work synergistically to provide effective resistance [Solanum tuberosum ADR1 (StADR1) or NbNRG1 induces a resistance response that suppresses the accumulation of potato virus X without visible HR [N. benthamiana require EDS1-SAG101 and NRG1 for activation of immunity [NbEDS1–NbPAD4–NbADR1 module has not yet been shown to contribute to immunity in N. benthamiana. An expression profiling study showed that NbNRG1 is required for 80% of the transcriptional changes induced by recognition of the bacterial XopQ1 effector in N. benthamiana, suggesting a major role in this response [NbADR1. The entire Arabidopsis AtEDS1–AtSAG101–AtNRG1 module can be transferred into N. benthamiana to mediate TIR-NLR-triggered immunity [AtEDS1 plus NbSAG101), or the AtEDS1–AtPAD4–AtADR1 module, cannot confer cell death mediated by TIR-NLRs or restriction of pathogen growth in N. benthamiana [R-NLRs coevolved separately in different species.The helper CCome CNLs ,65,91–94sistance . Howeversistance . Transiesible HR ,91. Thussible HR . EDS1-PAsible HR ,81,86,87sible HR ,96,97. Aimmunity ,80,87, wimmunity . Howeverthamiana ,86,91. TR domains and Ca2+ channel activity. A reasonable hypothesis is that the EDS1 family node evolved as an adapter complex to connect TNLs to a pre-existing CNL signalling pathway. No TNL, SAG101, or NRG1 proteins exist in monocots, but the monocot TIR-only protein BdTIR possesses NADase activity and can induce EDS1- and NRG1-dependent cell death in N. benthamiana [Arabidopsis TNLs including RPS4, RPS6, and SNC1 have been reported to interact with EDS1 [In summary, EDS1 family proteins seem to act as a signalling convergence node where the EDS1-PAD4 and EDS1-SAG101 heterocomplexes work complementarily to collect immune signals from NLRs. These heterocomplexes further activate either ADR1 or NRG1 to execute different immune responses, which require their CCthamiana ,20,79,83ith EDS1 ,98–100. ith EDS1 . Howeverith EDS1 ,15. The ith EDS1 .Plant NLRs have evolved direct and indirect recognition mechanisms to detect pathogens. Direct recognition is the dominant form in resistance to biotrophic filamentous pathogens such as fungi and oomycetes.Selection imposed by direct recognition leads to evolution of effector proteins through modification of surface residues that prevent interaction with host receptors.2+ channels on the PM while oligomerization of TNLs activates TIR domain enzymatic functions that produce potential signalling molecules.CNL and TNL proteins assemble into higher-order resistosomes after effector recognition. In CNL resistosomes, the CC domains seem to act as CaEDS1–PAD4–ADR1 and EDS1–SAG101–NRG1 modules work differently and synergistically for ETI.Mapping physical connections between TIR-NLRs, EDS1 family proteins and NRG1 or ADR1, are required to understand immune signal transmission during ETI.


These data could serve as a basis to setup national prevention strategies focused on socio-cultural, environmental, and behavioral aspects for a better management of HEV infection in Senegal.In West Africa, research on the hepatitis E virus (HEV) is barely covered, despite the recorded outbreaks. The low level of access to safe water and adequate sanitation is still one of the main factors of HEV spread in developing countries. HEV infection induces acute or sub-clinical liver diseases with a mortality rate ranging from 0.5 to 4%. The mortality rate is more alarming (15 to 25%) among pregnant women, especially in the last trimester of pregnancy. Herein, we conducted a multicentric socio-demographic and seroepidemiological survey of HEV in Senegal among pregnant women. A consecutive and non-redundant recruitment of participants was carried out over the period of 5 months, from March to July 2021. A total of 1227 consenting participants attending antenatal clinics responded to a standard questionnaire. Plasma samples were collected and tested for anti-HEV IgM and IgG by using the WANTAI HEV-IgM and IgG ELISA assay. The overall HEV seroprevalence was 7.8% (n = 96), with 0.5% (n = 6) and 7.4% (n = 91) for HEV IgM and HEV IgG, respectively. One of the participant samples was IgM/IgG-positive, while four were declared indeterminate to anti-HEV IgM as per the manufacturer’s instructions. From one locality to another, the seroprevalence of HEV antibodies varied from 0 to 1% for HEV IgM and from 1.5 to 10.5% for HEV IgG. The data also showed that seroprevalence varied significantly by marital status ( Hepatitis E is geographically a very heterogeneously distributed disease, being is present in both developed and developing countries. Hepatitis E virus (HEV) is a nonenveloped and quasi-enveloped virus with an icosahedral capsid. Its genomic structure is a single stranded positive-sense RNA containing three open reading frames ORF 1–3). The second ORF 2) is the one encoding for the protein of the viral capsid targeted by neutralizing antibodies directed against HEV [–3. The s is the oPaslahepevirus balayani and infecting mammals [To date, HEV genetic diversity shows eight different genotypes (HEV-1 to HEV-8), all belonging to  mammals ,5,6. Of  mammals ,4,5,7,8.Rocahepevirus ratti (rat hepatitis E virus) [Transmission is essentially by the fecal–oral route, causing generally asymptomatic infection ,9,10. ToE virus) ,22,23. IE virus) ,25. MoreE virus) ,27.Most infections are self-limited acute hepatitis in immunocompetent subjects. However, it can become severe with very high mortality rates in specific population groups, including pregnant women and immunosuppressed people ,30,31,32In developed countries, the seroprevalence of anti-HEV IgG was estimated to range from 7% to 21% . Kim et In year 2014, a localized epidemic was declared in the gold-bearing area of Kédougou located in the south-eastern region in Senegal. Local health authorities reported 19 deaths, and almost all of the infected individuals came from traditional gold panning sites, which concentrate a community of several workers from African countries, especially those bordering Senegal . Since tAccording to the 2018 Demographic and Health Survey report , the covFurthermore, beyond the health, economic, and environmental concerns, the issue of hepatitis E in West Africa is poorly covered, as evidenced by the very limited number of scientific studies ,48. FromThis prospective and multi-site study is part of a research program on the epidemiology of hepatitis E leaded by the GRBA-BE (Groupe de Recherche Biotechnologies Appliquées et Bioprocédés Environnementaux)/JEAI EPIVHE (Jeune Équipe Associée à l’IRD (Institut de Recherche pour le Développement) EPIVHE (Environnement et Epidémiologie du virus de l’hépatite E)) and his collaborators. Except for Dakar, the capital city of Senegal that housed two sites, all the three other regions had only one . RegardlThe inclusion criteria were pregnant woman from four weeks of amenorrhea confirmed by a pregnancy test and/or ultrasound, aged 18 years or over, resident for at least 6 months in the targeted localities, and consenting to participate in the study. Those with acute alcoholic hepatitis or drug-induced hepatitis and/or non-consenting were not included. On all the sites, a consecutive and non-redundant recruitment of participants was carried out over the period from March to July 2021. Socio-demographic and other relevant information to the study were collected with standardized survey forms and through individual and anonymous interviews. This consisted of collecting the address of the place of residence including trips over the past 12 months, access to sanitation and safe water supply services, individual and community hygiene , age, education level, regular income linked to a professional activity, and marital status. The data collected were entered directly into an Excel file.For each participant, a whole blood sample was taken on EDTA tubes for laboratory analysis. Lymphocyte separation was performed within two hours after collection and the plasma was frozen at −80 °C or stored at −20 °C on site until processing. An individual identification code per site and per patient was assigned to each sample. A written and signed informed consent form was obtained from each participant before the interview and sample collection. Ethical and administrative approvals were also obtained from the Senegalese National Ethics Committee for Health Research (N°000130/MSA/CNRES/Sec) and the Ministry of Public Health and Social Action (N°00000582/MSAS/DPRS/DR).As the study was carried out in the context of COVID-19 pandemic, in accordance with the recommendations of the local health authorities, our field teams have taken all the necessary measures to prevent and fight against the spread of the SARS-CoV-2 infection.To detect anti-HEV IgM and IgG, we used enzyme-linked immunosorbent assay (ELISA) from Wantai Biological Pharmacy Enterprise, Beijing, China (Wantai HEV-IgM ELISA and Wantai HEV-IgG ELISA), as per the manufacturer’s instructions. The specific HEV IgM and IgG antibodies were detected by adding plasma samples to ELISA plates precoated with recombinant HEV ORF2 antigens. HEV antibodies, if present in plasma sample, bind to these precoated antigens, which subsequently react with anti-human IgG or IgM conjugated to the enzyme horseradish peroxidase (HRP-conjugate). The reaction was then revealed by the addition of a chromogen . The reported sensitivities and specificities are in the range of 97.10–98.40% for HEV IgM antibodies and 99.08–99.90% for HEV IgG antibodies. In addition, the HEV-IgM represents the best marker for detecting the acute HEV infection, where RT-PCR cannot be performed . OpticalAll samples declared positive in the first tests were re-tested by Wantai HEV-IgM and HEV-IgG ELISA in accordance with the manufacturer’s instructions.® Pro Version 15.0.0 software . To assess the sociodemographic and environmental factors associated with exposure to HEV infection, we performed bivariate analyses. With regard to the data of binary variables whose frequencies were less than 5, chi-squared or Fisher’s exact tests were carried out. For all calculations, the confidence interval was set at 0.95. p-values < 0.05 were considered statistically significant.Statistical analysis was performed with JMPn = 50) and at the Gaspard Kamara Health Center (n = 116). At the other sites, we recruited 400, 397, and 264 participants, respectively, at the Regional Hospital Center of Saint-Louis, the Health District of Kédougou, and the NEMA Health Center of Ziguinchor. The median age was 25 years (age range 18–50 years). The distribution of age groups showed a greater representation of the 18–23-year-olds with 43%, 24–29-year-olds for 29.1%, followed by the 30–35-year-olds with 18.2%. Participants aged 36 and above represented only 9.7%. Of these, 3.6% (n = 45) were aged ≥ 40 years. Despite a low participation rate in Dakar and Ziguinchor localities, the total number of pregnant women enrolled was very satisfactory (n = 1227 vs. 1000 participants expected). The overall and site-specific results of the survey relating to hand hygiene, the disinfection of unpackaged fresh fruits and vegetables before consumption and access to safe drinking water and sanitation services, educational level, marital status, and regular income are summarized in A total of 1227 pregnant women attending antenatal consultations were recruited throughout five health facilities across four different geographic regions. In Dakar, the recruitment was carried out at the Obstetrical Gynecology Center of the Aristid Le Dantec hospital . Moreover, only 9% of them reached a higher level of education. Unlike the other localities, 25.9% of the participants in the city of Dakar reached a higher level of education. It should be noted that 92% of the participants in this study declared that they were married, and only 18.7% had regular income . On this last point, the highest rate was observed in Dakar (45.8%), which contrasts with that noted in Saint-Louis (11.8%).Overall, 78.4% of pregnant women reported having access to safe drinking water. However, a remarkably low rate was noted in Ziguinchor (37.1%). Indeed, 42.8% of participants reported not having access to sanitation services, including adequate toilets. The level of access for women residing in other localities was relatively acceptable and varied from 91.4% to 100%.Regarding hand hygiene, overall, more than 90% of participants declared that they systematically washed their hands, especially after using the toilet. In addition, 71.3%, 87.7%, and 100% of the participants, respectively, from Saint-Louis, Kédougou, and Dakar declared that they proceeded to the decontamination of food matrices (fruits and vegetables), particularly those not wrapped and eaten raw. However, among respondents from Ziguinchor, almost 30% said they did not systematically decontaminate fruits and vegetables eaten raw .n = 6) and 7.4% (n = 91) of participants were positive for IgM and IgG antibodies to HEV, respectively. Only one sample was positive for both IgM and IgG. A total of 4 samples were declared indeterminate to anti-HEV IgM, despite having been re-tested according to the WANTAI HEV-IgM and IgG ELISA detection kit manufacturer’s instructions. The observed prevalence rate of HEV varied from one geographic region to another. For anti-HEV IgM, no positive sample was identified in Dakar and Ziguinchor, while it was 0.5 and 1% for Saint-Louis and Kédougou, respectively. The HEV IgG seroprevalence was higher in the regions of Saint-Louis and Kédougou, with 10.5% and 9.6%, respectively, while in Dakar and Ziguinchor, it was 4.2 and 1.5%, respectively. Between sites, the differences observed were statistically significant only for the IgG seroprevalence (p = 0.0133)  .p-values were 0.0372 and 0.0048 for IgM and IgG, respectively). With regard to age groups, this association is more remarkable among young adults (18–35 years), where more than 80% of infections were observed (p < 0.0001), economic situation (regular income) (p = 0.0043), and access to sanitation services  (p = 0.0006) were significantly associated with exposure to HEV  and 7.4% (n = 91) of IgM and IgG, respectively. Otherwise, this overall seroprevalence hides disparities between sites  in pregnant women attending antenatal consultations in five health facilities distributed in four different geographical regions. The overall HEV seroprevalence found was high (7.8%), with 0.4% . This situation could be linked to the fact that recruitment had taken place in the midst of a crisis due to the COVID-19 pandemic. Dakar, the capital city, concentrated more cases across the country, and therefore its health facilities were rarely visited by the population for fear of contracting COVID-19. This low participation rate coincides with the fact that none of plasma samples tested revealed anti-HEV IgM positivity, an indicator of acute infection, while 7 (4.2%) were positive for anti-HEV IgG antibodies, indicating previous exposure to HEV. Previous studies carried out in Dakar also revealed rare cases of hepatitis E infections [Hight rate of participation was obtained, which could be considered as indicative of good attendance at prenatal care structures. Compared to other regions, Dakar recorded lower participation rates  found in Saint-Louis participants, the positivity rates for anti-HEV IgM (1%) and IgG (9.6%) in pregnant women in Kédougou were higher than those of the other localities. While contexts were different, the data of this study contrast with those reported during the 2014 epidemic. The prevalence rates of IgM and IgG in individuals who were identified in contact with people who tested positive for hepatitis E by RT-PCR and suspected on the basis of symptoms were 38.8% and 27.5% for IgM and IgG, respectively. It should be noted that this study population of the 2014 epidemic had previously tested negative by RT-PCR. This study reports that the risk of exposure was statistically higher in men (77.3%) than in women (22.7%). However, serious cases have been observed mainly in women, particularly those who are pregnant. Moreover, among them, two cases of death due to hepatitis E were noted during this study .Our work also has some limitations. First, the study sites are all located in urban areas. We were also unable to establish a link between seroprevalence of HEV infection and the pregnancy term. Another limitation is the lack of molecular data to confirm acute infection. This aspect is planned in further development of the project.With a satisfactory participation rate (122.7%) related to the expected sampling, this seroepidemiological survey confirms the circulation of HEV in Senegal and in particular contributes to a better understanding of hepatitis E virus infection in pregnant women with a national seroprevalence of 7.8%. Our data confirm also that HEV is a poverty-linked infection, as evidenced by the significant association of seroprevalence with regular income and access to sanitation services. Thus, as a means to mitigate this emerging infection, a holistic intervention approach should be adopted.


Currently, the most widely used protocol for the transportation layer of computer networks for reliable transportation is the Transmission Control Protocol (TCP). However, TCP has some problems such as high handshake delay, head-of-line (HOL) blocking, and so on. To solve these problems, Google proposed the Quick User Datagram Protocol Internet Connection (QUIC) protocol, which supports 0-1 round-trip time (RTT) handshake, a congestion control algorithm configuration in user mode. So far, the QUIC protocol has been integrated with traditional congestion control algorithms, which are not efficient in numerous scenarios. To solve this problem, we propose an efficient congestion control mechanism on the basis of deep reinforcement learning (DRL), i.e., proximal bandwidth-delay quick optimization (PBQ) for QUIC, which combines traditional bottleneck bandwidth and round-trip propagation time (BBR) with proximal policy optimization (PPO). In PBQ, the PPO agent outputs the congestion window (CWnd) and improves itself according to network state, and the BBR specifies the pacing rate of the client. Then, we apply the presented PBQ to QUIC and form a new version of QUIC, i.e., PBQ-enhanced QUIC. The experimental results show that the proposed PBQ-enhanced QUIC achieves much better performance in both throughput and RTT than existing popular versions of QUIC, such as QUIC with Cubic and QUIC with BBR. At present, computer networks remain the essential platform for information interaction, where the transport layer plays an influential role. The emergence of modern applications, such as video live broadcast and Internet of Things (IoT), has imposed higher demands on throughput, packet loss rate, and network delay. The development of wireless transmission technologies such as 5G and WiFi has made the network environment even more complex. The Transmission Control Protocol (TCP), as a widely used protocol, experiences problems such as large handshake delay, head-of-line (HOL) blocking, and protocol solidification, which increasingly affect network performance. Compared with TCP, the User Datagram Protocol (UDP) is more efficient for real-time transmission but lacks reliability.In 2012, Google proposed the Quick UDP Internet Connection (QUIC) protocol [For both TCP and QUIC protocols, congestion control is one of the core mechanisms. The basic logic of TCP congestion control contains congestion sensing and the corresponding disposal pattern, which improves the network utilization by estimating the bandwidth-delay product (BDP) of the link and adjusting the send rate of clients. Since the first congestion control algorithm, Tahoe , was proRecently, researchers have started to design TCP congestion control algorithms using machine learning algorithms. There are numerous versions of TCP based on supervised learning, such as TCP with DeePCCI  and TCP However, for these popular versions of QUIC, only heuristic congestion control algorithms are applied. Most heuristic congestion control algorithms commonly perceive the network state based on simple network models and adopt a fixed strategy, i.e., shrinking the window when packet loss occurs or RTT increases, and augmenting the window when an acknowledge character (ACK) is received. Such a simple strategy makes heuristic congestion control algorithms unable to achieve optimal results in dynamic and changeable network environments. For example, in the WiFi scenario, where obstacles and human activity affect network quality, packet loss events do not imply the occurrence of congestion. However, heuristic congestion control algorithms cannot distinguish that. This issue leads to poor performance of the QUIC protocol in terms of throughput and latency when the network settings change. Therefore, to enable the QUIC to achieve better performance in different network environments, we tried to design DRL-enhanced QUIC using the merits of DRL in environment awareness and decision making.First, we developed a novel congestion control mechanism, referred to as proximal bandwidth-delay quick optimization (PBQ) by combining proximal policy optimization (PPO)  with traSecond, for the purpose of reducing the action space and establishing the connection of the values of the congestion window (CWnd) for each interaction, we used continuous action ratio as the output action of PBQ’s agent. Additionally, in the design of the utility function, we used a relatively simple formulation of the objective function as the optimization objective and introduced a delay constraint. By doing so, our proposed PBQ-enhanced QUIC achieves higher throughput and maintains a low RTT.Third, we built a reinforcement learning environment for QUIC on the network simulation software ns-3, where we trained and tested PBQ-enhanced QUIC. The experimental results showed that our presented PBQ-enhanced QUIC achieves much better RTT and throughput performance than existing popular versions of QUIC, such as QUIC with BBR and QUIC with Cubic .The contributions of this work can be summarized as follows:The organization of the rest of this paper is as follows: The QUIC protocol is a secure and reliable data transfer protocol first proposed by Google in 2012, which was released as a standardized version of QUIC, RFC 9000 , by the TCP is a plaintext transport protocol and transport layer security (TLS) is required to implement data encryption transmission. In TLS 1.2, two RTTs are required for the TLS handshake phase and three RTTs for the total handshake delay. Under TLS 1.3, the TLS handshake phase requires one RTT, and the handshake phase still requires two RTTs.Comparatively, the QUIC protocol optimizes the handshake process. In the handshake phase, QUIC incorporates the transmission parameters into the encryption part. When the first connection is established, the client sends authentication- and encryption-related information to the server. It takes only one RTT to establish a connection. Alternatively, we can use quantum key distribution to replace the original encryption information exchange . When thMultiplexing is multiple streams on a connection at the same time, commonly on a Hyper Text Transfer Protocol (HTTP) stream. For HTTP/2, a TCP connection can support multiple HTTP streams. However, HOL blocking in the TCP protocol causes interference between HTTP streams, which affects their performance. In advance, multiple streams can be created on a single QUIC connection, which reduces the handshake frequency. The QUIC protocol is implemented based on UDP. Streams on the same QUIC connection are independent of each other, which solves the HOL blocking problem.One TCP connection is known to be identified by a quintuple, i.e., <ion port . If one Particularly, before the client’s IP changes, the endpoints communicate via a nondetection packet. After IP changes, the path detection is performed to verify the reachability before connection migration starts. If the path detection fails, the connection migration cannot be performed; otherwise, a fresh connection is established. The IP address is verified between the client and the server, and the endpoint holding the latest IP address of the peer migrates. When migration occurs, the congestion control part and the reliable transport protocol estimation part of the path need to be reset. After the connection migrates, it sends a nonprobe packet.The QUIC protocol is a reliable UDP-based data transfer protocol, which makes it compatible with existing network protocols. The congestion control algorithm in TCP is implemented in kernel mode, and if an upgrade is performed, the kernel needs to be recompiled. However, the QUIC protocol straddles kernel mode and user mode, and its congestion control part is in user mode. Thus, it can be easily upgraded. In particular, the QUIC protocol supports the configuration of different congestion control algorithms for applications, making it possible to optimize for specific applications.In this section, we describe PBQ and its application to QUIC to form the PBQ-enhanced QUIC.For clarity, Monitoring ModuleWe set the network state collection interval to 100 ms, and the designed state quantity is shown in Reward Function Designt, t. Then, we formulate an optimization problem to maximize the linear utility function under a given RTT constraint, i.e., t, and t.We trained PBQ using a linear function with constraints. First, we define a linear utility function as Action DesignReinforcement learning action types can be divided into two categories, discrete and continuous actions. We first used discrete actions, but analyzing the experimental results, we found that when using discrete actions, the output of the agent considerably fluctuated, and it was difficult to achieve better performance in the initial stages of the interaction. In general, the discrete action does not favor the early stability of the network links. The final solution in this study draws on the additive increase multiplicative decrease (AIMD)  idea in Learning Algorithm for PBQFor the DRL agent, PPO is employed, which is a classical actor-critic algorithm. We used tanh as the activation function in both actor and critic neural networks. Because the state transitions in traditional congestion algorithms are not complex, we preferred to build a simpler neural network and train on it. Finally, we constructed a three-layer neural network, where the hidden layer contains 64 neurons.D is initialized, which is used to store state, action and reward. The policy parameters D. The policy parameters Algorithm 1 PBQ’s learning algorithm.1:D and training episode Initialize replay memory 2:Initialize policy parameters 3:fordo4:     Reset environment, obtain initial state 5:     6:for t = 1 to do     7:if time to play PPO action then         8:             Run policy 9:             Map 10:           Perform 11:else        12:            Play a BBR action, perform 13:end if        14:D        Collect 15:        16:if then        17:            18:end if        19:end for      20:end forFor clarity, the PBQ training phase is summarized in Algorithm 1. On lines 1–2 of Algorithm 1, the training episode PacerThe Pacer module is responsible for distributing the actions output by the Decision module to the corresponding clients. The action distribution is driven by an update callback for the CWnd and an update callback for the pacing rate. For pacing rate, when the client receives an ACK or packet loss occurs, the underlying BBR adjusts the pacing rate and triggers a pacing rate update callback. For CWnd, the Decision module receives the updated network state from the Monitoring module; the RL part outputs We specifically designed states and actions. The Monitoring module periodically collects the state of the environment and sends the processed data to the Decision module. We collected a number of environment states, including pacing rate, current RTT and minimum RTT, interval, packet loss rate, CWnd, and so on. The output of the Pacer module includes the CWnd and pacing rate of the senders. The BBR regulates the pacing rate of the clients, and the DRL agent gives the congestion window as the predicted BDP. Then, the Pacer module changes the sending behavior of the clients.We tested the PBQ-enhanced QUIC in various scenarios on the open-source network simulator ns-3  and compThe application of DRL methods is inseparable from the interaction with the environment. Several researchers have implemented their own simulation environments, but they all target the TCP domain, and there is no mature solution for the simulation environment of the QUIC protocol alone. At the same time, we think that the development of a network simulation environment is a huge and meticulous project that should be focused on the study of congestion control algorithms; therefore, we chose the ns-3 platform to build the training and testing environment. We built our own simulation environment based on NS3-gym  and QuicWe also applied the PPO method to the congestion control part of QUIC. We trained PPO and PBQ on the link shown in As illustrated in Similarly, we compared PBQ-enhanced QUIC with QUIC using current learning-based congestion control algorithm Remy and heuristic algorithms such as Bic , Cubic, In traditional algorithms, BBR is based on network modeling, while the remaining algorithms take packet loss events as congestion occurrence signals. In this part, we still used the dumbbell link in We tested the proposed algorithm using a previously trained model in a different network scenario. The throughput changes with the packet loss rate as illustrated in When packet loss occurs, QUIC with congestion control algorithms that take packet loss events as a signal, such as QUIC with Cubic and QUIC with NewReno, frequently enter fast recovery, resulting in low throughput and low RTT. While QUIC with BBR requires constant probing of the network, QUIC with Remy relies on a state-action table. It is difficult for them to balance throughput and RTT. Our algorithm can efficiently identify the overall state of the network and can output relevant actions by periodically collecting the network state. As the packet loss rate increases, the throughput performance of our algorithm is less affected, and it is the best among the different packet loss rates. Furthermore, our proposed algorithm achieves higher throughput analso has better packet loss tolerance ability than QUIC with Remy and QUIC with BBR.Then, the packet loss rate was set to 2.5%, and we modified the number of flows and compared the throughput and delay performance of different QUIC implementations. The results are shown as Owing to the presence of random packet loss, algorithms that take packet loss events as congestion occurrence signals fail to accurately identify the cause of congestion. In the policies of these congestion control methods, the current link can only support a low throughput; thus, the throughput is at a low level. In this case, the flows barely affect each other. As a result, as shown in In this study, we first developed a two-level regulatory mechanism PBQ, which combines the heuristic algorithms BBR and DRL to approximate PPO. The convergence rate of the model is accelerated by using BBR to estimate the specific transmission rate. Moreover, we proposed PBQ-enhanced QUIC, an implementation of QUIC that uses PBQ as a congestion control algorithm. Unlike QUIC with heuristic congestion control algorithms, our QUIC implementation learns congestion control rules from experience by using RL signals. Therefore, our QUIC implementation can be better adapted to various network settings.As shown in In future work, we plan to build a testbed in real-world networks and test PBQ-enhanced QUIC on it. We will improve the PBQ-enhanced QUIC based on its performance in real-world networks. Moreover, different applications have different requirements on network metrics, so we plan to design congestion control algorithms for different applications by taking advantage of the feature that the congestion control part of QUIC is implemented in user mode. We expect different applications to perform efficiently on the same network.