NOTCH2NLC gene. As case studies have reported dynamic cortical perfusion changes in NIID, this study aimed to explore the cerebral perfusion pattern in NIID patients.Neuronal intranuclear inclusion disease (NIID), which pathogenesis remains largely unclear, is a neurodegenerative disease caused by GGC repeat expansion in A total of 38 NIID patients and 34 healthy controls (HCs) were recruited, and 2 NIID patients who had had episodic symptoms within 2 months were excluded. Data on demographic characteristics and clinical features were collected. All participants underwent three-dimensional pseudo-continuous arterial spin labeling perfusion magnetic resonance imaging (MRI) scanning. Voxel-based comparisons of cerebral blood flow (CBF) were conducted.p <0.05). When comparing the mean CBF value of the whole brain, no significant differences were observed between NIID patients and HCs . Voxel-based analysis showed no significant difference in cerebral perfusion between NIID patients with and without episodic symptoms. The perfusion within the bilateral middle frontal and anterior cingulate gyri showed positive correlations with MMSE and MoCA scores using age, sex, and education as covariates (p <0.005 uncorrected).NIID patients showed decreased perfusion in the cortex but increased perfusion in the deep brain regions compared with HCs. The regions with significant hypoperfusion were distributed in the bilateral frontal, temporal, parietal, and occipital gyri, with the left frontal gyrus being the most prominent. The regions with significant hyperperfusion included the bilateral basal ganglia, midbrain, pons, para-hippocampal, and parts of the bilateral cerebellum, fusiform, lingual, rectus, orbital, and cingulum anterior gyri, which were adjacent to the midline (all FDR-corrected NIID patients exhibited characteristic cortical hypoperfusion and deep brain hyperperfusion. The perfusion in the bilateral frontal lobe and cingulate gyrus was correlated with the severity of cognitive dysfunction. Cerebral perfusion change may be involved in NIID pathophysiology and serve as a potential indicator for monitoring NIID severity and progression. NOTCH2NLC gene  is a progressive neurodegenerative disease caused by GGC repeat expansion in the 5′ untranslated region of NLC gene . The cliNLC gene .The pathogenesis of these symptoms in NIID remains largely unclear. Recent case studies have reported dynamic cerebral perfusion changes during episodic neurogenic symptoms attacks in NIID patients. Patients with encephalitic episodes, stroke-like episodes, and recurrent disturbance of consciousness show regional decreased cortical cerebral blood flow (CBF) in the hyperacute stage  , subsequUtilizing magnetically labeled blood plasma as an endogenous contrast media, arterial spin labeling (ASL) perfusion is a non-invasive, rapidly repeatable method for quantitatively measuring CBF. While ASL-MRI provides information comparable to fluorodeoxyglucose (FDG)-positron emission tomography (PET) , it doesNOTCH2NLC gene larger than 60  patients clinically presenting with neurologic symptoms in accordance with NIID, including cognitive impairment, parkinsonism, tremor, autonomic dysfunction, peripheral neuropathy, myopathy, ataxia, and various episodic neurogenic symptoms; (2) skin biopsy showing eosinophilic hyaline intranuclear inclusions on hematoxylin and eosin (H&E) staining in adipocytes, fibroblasts, sweat gland cells, or other cells, which were anti-p62-positive on immunochemical staining; (3) the number of GGC repeats in the 5′-UTR of  than 60 . Two patDemographics and clinical characteristics of patients, including sex, age, education level, disease onset age, disease duration, clinical symptoms, and physical examinations, were collected. Cognitive function was evaluated by mini-mental state examination (MMSE) and Montreal Cognitive Assessment (MoCA). According to whether patients had ever suffered from episodic symptoms since disease onset, NIID patients were divided into NIID with and without episodic symptoms.Magnetic resonance imaging (MRI), including 3D T1 weighted imaging (T1WI) and ASL, was performed using a 3.0 Tesla MR scanner . Sagittal 3D T1W images were acquired using magnetization-prepared rapid gradient echo (MPRAGE) . ASL images were obtained using 3D axial acquisition with gradient and spin echo (GRASE) . Other conventional sequences  were also performed to exclude major neurological disorders, such as tumors or stroke.1) and custom scripts on MATLAB software (MATLAB 2019b) with the following steps: (1) co-registration of the M0 image (obtained with the pCASL acquisition and the same image space with CBF) with the anatomical T1W image; (2) normalization of T1W images to MNI template using Segment in SPM; (3) CBF image warped into the MNI space using the forward transformation matrix derived from T1W segmentation. For whole brain level comparisons, the mean CBF within the whole brain was calculated by home-developed Matlab scripts.Cerebral blood flow (CBF) maps were generated with the software provided by the scanner vendor. Imaging data were preprocessed using Statistical Parametric Mapping 12  was considered statistically significant.Using the SPSS 25.0 statistical package, demographic and clinical data of patients in different groups were compared using the χt-tests between the two groups, analysis of covariance (ANCOA) of the subgroups, and the correlation between CBF and clinical variables were analyzed using linear regression, considering sex, age, and education level as covariates. Multiple comparisons were corrected with a false discovery rate (FDR) at p <0.05. If significant clusters were not found, a more liberal voxel-wise threshold at uncorrected p <0.005 with a cluster size of 50 voxels was adopted.Voxel-based analyses of CBF within brain tissue were performed using SPM, including two-sample p values >0.05). Significantly lower scores of MMSE and MoCA were found in the NIID group than that in the HC group .A total of 36 patients with NIID and 34 age- and sex-matched HCs were included in the analysis. The demographic and clinical features of the participants are summarized in p <0.05, the regions with significant hypoperfusion were distributed in the bilateral frontal, temporal, parietal, and occipital gyri, with the left frontal gyrus being the most prominent. Furthermore, the regions with significant hyperperfusion included the bilateral basal ganglia, midbrain, pons, para-hippocampal gyrus, and parts of the bilateral cerebellum, fusiform, lingual, rectus, orbital, and cingulum anterior gyri, which were adjacent to the midline .When comparing the mean CBF value of the whole brain, no significant differences were observed between patients with NIID and HCs (28.81 ± 10.1 vs. NIID patients with episodic symptoms (n = 14) and HCs vs. NIID patients without episodic symptoms . Details regarding anatomical regions for each contrast are shown in A similar pattern of perfusion change was found in the comparisons of HCs p <0.005 uncorrected, Abnormal perfusion within the bilateral middle frontal and anterior cingulate gyri showed positive correlations with cognitive function determined by MMSE and MoCA scores using age, sex, and education as covariates (NOTCH2NLC gene has been recognized as the causative mutation of NIID (GGC repeat expansion in the 5′-untranslated region (5′-UTR) of  of NIID ; however of NIID . The preWe found that deep brain regions in NIID patients were excessively hyperperfused rather than reduced. When comparing the mean CBF value of the whole brain between NIID patients and HCs, the reverse perfusion change in the cortex and deep brain regions could be offset by each other. Interestingly, the imaging changes of the two areas on conventional head MRI of NIID patients are also different. The cerebral cortex with decreased perfusion on ASL manifests as chronic cortical atrophy, while the deep brain regions with hyperperfusion on ASL typically exhibit extensive white matter T2/Flair hyperintensity, which might be related to that hyperperfusion state bringing about a blood-brain barrier breakthrough and consequentially extravasation of fluid and vasogenic edema .The dynamic brain perfusion changes during episodic neurogenic symptoms in NIID patients, showing decreased CBF in focal cortical regions in the hyperacute stage and subsequent hyperperfusion lasting for days to several weeks , are simTaken as a whole, cerebral perfusion in NIID patients exhibits a high-to-low gradient from the deep brain to the cortex. This characteristic perfusion pattern probably might result from the combination of multiple factors. First, the perfusion gradient was exactly consistent with the pressure gradient across cerebral arteries, with a marked drop in blood pressure from large and medium-sized cerebral vessels to cerebral peripheral beds . At the Despite the promising results, the limitations of this study should be considered. First, this study included 14 NIID patients who had ever had episodic attacks. Although the interval between the last episode and the MRI scan was more than 2 months, some patients might continue to have focal cortical hyperperfusion after the episode for a long time or develop excessive hypoperfusion in the focal cortex due to focal brain atrophy. As we have compared the cerebral perfusion between NIID patients with and without episodic attacks without finding a significant difference, the impact on study results was likely to be negligible. Second, the clinical manifestations of NIID are highly heterogeneous, and there is a lack of a verified scale for evaluating the severity of the disease, which makes it impossible to accurately evaluate the correlation between NIID severity and cerebral perfusion. Here, we only analyzed the correlation between cognitive function and perfusion in NIID. Third, as a preliminary study, we observed the cerebral perfusion change of NIID using ASL, and more data were required to further confirm our findings. In addition, it is necessary to evaluate cerebrovascular reactivity and autoregulative capacity in future studies to better clarify the underlying pathophysiological mechanisms.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by Medical Ethics Committee of Beijing Tiantan Hospital, Capital Medical University. The patients/participants provided their written informed consent to participate in this study.Z-QZ and H-FT: study concept, design, and drafting of the manuscript. H-FT, T-TH, Y-YD, AW, Z-ZZ, YZ, and SL: acquisition of data. H-FT, T-TH, Z-QZ, Y-YD, and Z-ZZ: analysis and interpretation of the data. Z-QZ and Y-YD: study supervision. Z-QZ: critical revision of the manuscript. All authors contributed to the article and approved the submitted version.


I am really excited to be the first Editor in Chief of Skin Health and Disease (SHD), a collaboration between the British Association of Dermatologists (BAD), in our centenary year, and Wiley, the publishers. I thoroughly enjoyed my time as Editor in Chief of Clinical and Experimental Dermatology (CED), from January 2013 to December 2018, and I am now eager for a new challenge. The original BAD journal is the British Journal of Dermatology (BJD), which started in 1888. It was renamed as the ‘British Journal of Dermatology and Syphilis’ in 1917 and reverted to its original name only in 1950. The BJD is one of the oldest and most highly cited international dermatology journals. It publishes the highest‐quality research to advance the understanding and management of skin disease to improve patient outcomes. CED started life as the ‘Transactions of the London Dermatological Society’ in 1911, have previously been known as the ‘Transactions of the St John’s Dermatological Society’. It was transferred to the BAD in 1976 and renamed CED. CED is a highly respected and readable provider of original articles and continuing professional development and CED has been rebranded as the BAD’s education journal.SHD now joins its older siblings, as the BAD and Wiley’s first fully open‐access (OA) Dermatology journal. Wiley has 20 dermatology titles, by far the biggest grouping of all the major publishers . Wiley is an American academic publisher, that was established in 1807. It merged with Blackwell’s , the original publishers of BJD and CED, in 2007. The BJD and CED have a longstanding relationship with Blackwell’s and more recently Wiley Blackwell, going back to 1978.Articles are published very quicklyArticles are freely accessible to readersCertain article types may be more easily published OA Some funders require it This new journal is their first purely OA Dermatology journal. So, what is OA publishing? OA publishing is not new. Many established journals, such as BJD and CED, are hybrid journals, publishing a small proportion of their articles in exchange for an article‐processing charge (APC). This is the hybrid model. For a pure OA journal, the APC will have to be paid for every article, unless the relevant university has an agreement with the publisher to waive the APC. There are agreements currently with many universities in the United Kingdom, Germany, the Netherlands, Austria, Sweden, Norway, Finland, Hungary and currently in the United States, we have agreements with Ohio and Virginia. Authors from these regions will not necessarily have to pay to publish. What are the advantages of publishing OA?SHD is a multidisciplinary international open access journal covering all aspects of dermatology including basic science, translational and clinical research. We especially welcome cutting‐edge interdisciplinary and multiprofessional dermatology research. This includes genetics, immunology, pathology, surgery or pure clinical studies, as well as artificial intelligence in dermatology and teledermatology studies. The overarching aim of the journal is to improve patient outcomes by increasing our understanding of skin problems at every stage from disease pathogenesis to its treatment and prevention.We will publish research articles, reviews, case reports, method papers, protocols, negative studies and pilot studies if the article can demonstrate robust methodology, scientific validity and reliability. All papers will undergo rigorous and fast peer review, as well as rapid publication times.shd@bad.org.ukWelcome to your new journal! For any pre‐submission enquiries contact, No conflict of interests have been declared.


Brown rice powder is underutilized mainly due to its lower starch digestibility and poor processing performance. The present study investigated the potential of steam explosion on the improvement of nutritional and physicochemical characteristic in brown rice powder and rheological property of paste. Compared with native brown rice powder, steam explosion at 0.5 MPa for 7 min increased the water-extractable arabinoxylans (5.77%), reducing sugar content (21.04%), and iodine blue value (30.38%), which indicated steam explosion that destroyed the intact cells of brown rice. Later the crystalline structure of brown rice powder was destroyed into an amorphous structure by steam explosion. Steam explosion enhanced the degree of gelatinization (4.76~351.85%) and solvent retention capacity (SRC) of brown rice powder, compared with native sample. The effect on the intact cells and starch structure of brown rice caused the starch digestibility enhancement remarkable. Viscoelastic profiles confirmed that steam explosion weakened the paste strength and elasticity corresponded with hardness and cohesiveness by increasing the loss factor (tanδ). This work provided important information for brown rice powder modified by steam explosion  with good nutritional property (nutrients and digestibility) and processability . Steam exploded brown rice powder  could serve as a potential ingredient widely used in food products. Brown rice has been categorized as one of the potent functional foods because of its high bioactive compounds content and biological activity . As an iRecently, researchers have shown an increased interest in the steam explosion applications. Steam explosion is a novel hydrothermal processing technology in food industry with high efficiency and low energy consumption, which was often employed in lignocellulosic or high-protein materials –9. Steamin vitro starch digestibility), and processibility (solvent retention capacity (SRC) and textural and rheological properties) of brown rice powder were evaluated. These results upon evaluation of nutritional, physicochemical, and rheological characterization in the investigated brown rice powders will have the guiding meaning for the application of steam explosion as an innovative modifying technology in the cereal processing industry and help to identify a new source of flour in food applications for the development of whole grain products from brown rice powder.The aim of this work was to investigate the effect of steam explosion on improvement of the digestibility and rheological property of brown rice powder. The effects of steam explosion on the structural characteristic (scanning electronic microscopy and X-ray diffraction), nutritional characteristic  and a steam generator  . 500 g oThe scanning electronic microscopy (SEM)  was used to obtain SEM images of brown rice powder at a voltage of 1.00 kV.The structures of brown rice samples were measured using a diffractometer . The samples were scanned from 5 to 80° with a scanning speed of 0.02°/s.* means lightness of the powder, a* indicates green or red-purple color and b* indicates yellow or blue color . Lue color . Chroma ue color , hue  and incubated at 60°C for 45 min. Iodine blue value was estimated using protocol established by the method . Total arabinoxylans and water-extractable arabinoxylans contents were determined using the Hashimoto's method . The rede method ; brown re method  with mod5 U/mL)  and 3 mL of deionized water to prepare digestive enzyme solution. Brown rice powders (500 mg) was mixed with 14 mL of deionized water and boiled in a water bath for 5 min. Then, 1 mL of digestive enzyme solution was added, shaken, and incubated at 37°C. Sample solutions of 0.2 mL were taken out after 20, 60, 120, 180, and 240 min and added 80% ethanol solution (5 mL) immediately.Starch digestibility was determined as the previous report , 23–26 wThe SRC tests, included lactic acid (LA), sodium carbonate (SC), sucrose (Suc), and water (W), were measured according to the AACC International Approved Method 56-11.02.The pastes were prepared in the 100-mL centrifugal tube with 6 g powders and 60 mL deionized water; the suspensions were shaken in 95°C water for 30 min and stored at 4°C. The textural properties of pastes were tested by a CT3 Texture Analyzer  with cylinder probe of TA4/1000, and the test speed was set at 0.5 mm/s and the degree of deformation of gel was 30%.The dynamic rheological property of all samples was investigated by an HR-1 Rheometer  based on a method , 28. 6 gp < 0.05). The results were reported as mean ± standard deviation.Three replicate tests were carried out and the average values were reported. Experimental data were processed by one-way analysis of variance using IBM SPSS Statistics 20  with Duncan's multiple range test  as compared to native powder . Color measurements indicated that steam explosion treatment of brown rice yielded a darker color . A similar result was obtained by Zhao et al. (p > 0.05), which indicated stability of yellow color in brown rice powders. The Hue angle values increased from about 0.43 to 0.47 during steam explosion process at 0.5 MPa for 7 min. It suggested increment from a more green color to an orange-red color of steam exploded brown rice. The Hue values of steam exploded powders were gradually increased from 0.41 to 0.46 with the rising of treated pressure from 0.3 to 0.7 MPa for 5 min. The browning index represented the purity of brown color which was an important parameter in processes where enzymatic and non-enzymatic browning took place (p < 0.01) between L* and ΔE (r = −0.987), L* and browning index (r = −0.894), a* and b* (r = −0.785), a* and Hue (r = −0.886), a* and browning index (r = −0.732), while b* and Hue (r = 0.975), b* and browning index (r = 0.757), Hue and browning index (r = 0.759), ΔE and browning index (r = 0.899) showed significant positive relationship (p < 0.01).The color profiles of L, aectively . The steo et al. , whereaso et al. , 28. Theo et al. . No chanok place , 28, 36.ok place . There wp < 0.05) compared with that of NBR. When the steam explosion intensity was >0.5 MPa for 5 min, it could promote the conversion of insoluble dietary fiber to soluble dietary fiber, which indicated steam explosion had the effect of breaking the cell wall of rice bran , which indicated that steam explosion assisted milling damaged cell and starch structure. High-temperature treatment could improve the quality of brown rice, the iodine blue value of high-temperature air fluidization-treated brown rice at 130°C increased significantly, indicating that the quality of brown rice is higher than that of untreated brown rice  the rapidly digestible starch content, however, significantly decreased (p < 0.05) the slowly digestible starch and resistant starch content of brown rice powders. The rapidly digestible starch and resistant starch of steam exploded powders were gradually increased from 36.23 to 40.39% and 21.81 to 34.33% with the rising of treated pressure from 0.3 to 0.7 MPa for 5 min. The rapidly digestible starch and resistant starch of steam exploded powders were gradually increased from 34.95 to 41.56% and 16.05 to 34.52% with the rising of treated time from 3 min to 7 min at 0.5 MPa. The slowly digestible starch content of steam exploded samples was gradually decreased from 4.09 to 1.07% with the rising of treated pressure from 0.3 to 0.7 MPa for 5 min. The rapidly digestible starch content increased and slowly digestible starch and resistant starch content of brown rice powder decreased after steam explosion treatment, which could be due to steam explosion and broken the complex physicochemical mechanisms, which was known as “biomass recalcitrance” for protecting its structural carbohydrates from attack by enzymes  between SDS and W-SRC (r = −0.916), LA-SRC (r = −0.904), Suc-SRC (r = −0.870), SC-SRC (r = −0.916), while water-extractable arabinoxylans and LA-SRC , Suc-SRC , SC-SRC , RDS and LA-SRC , Suc-SRC , SC-SRC  showed significant positive relationship. Brown rice powder modification by steam explosion at 0.5 MPa for 7 min had the highest W-SRC (299.42%), LA-SRC (334.55%), Suc-SRC (318.33%), and SC-SRC (408.42%), respectively, that of native were 92.30, 98.60, 94.51, and 93.56%, respectively.SRC was deemed to be an efficient method to evaluate wheat flour quality; it is a special method for predicting the flour function by estimating the relative contributions of individual flour compounds to water absorption , which ap < 0.01). Gumminess recognized as the energy is required to destroy a semi-solid food to a state ready for swallowing. With semisolid food products, hardness was low  could be widely used in food products.The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding authors.FK and XG: conceptualization, resources, and supervision. FK, YL, and QZ: methodology and validation. FK: software, formal analysis, data curation, writing-original draft preparation, writing-review and editing, project administration, and funding acquisition. QZ, FK, XD, YD, and YL: investigation. QZ and FK: visualization. All authors have read and agreed to the published version of the manuscript.This study was financially supported by the Open Project of Liaocheng University Animal Husbandry Discipline (No. 319312101-08), the Doctoral Research Startup Foundation of Liaocheng University (No. 318052122), the Research and Development of Key Technology of Nutrition Enhancement of Bone-derived Pet Food (No. K22LD04), and the Project of Shandong Province Higher Educational Science and Technology Program for Youth (No. 2019KJF028).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.


Coronaviridae family) causes upper respiratory disease associated with severe economic losses in the poultry industry worldwide. Here, we report for the first time in Kenya and the Eastern African region two novel AvCoVs, designated IBV/ck/KE/1920/A374/2017 (A374/17) and AvCoV/ck/KE/1922/A376/2017 (A376/17), inadvertently discovered using random nontargeted next-generation sequencing (NGS) of cloacal swabs collected from indigenous chickens. Despite having genome organization (5′UTR-[Rep1a/1ab-S-3a-3b-E-M-4b-4c-5a-5b-N-6b]-3′UTR), canonical conservation of essential genes and size (~27.6 kb) typical of IBVs, the Kenyan isolates do not phylogenetically cluster with any genotypes of the 37 IBV lineages and 26 unique variants (UVs). Excluding the spike gene, genome sequences of A374/17 and A376/17 are only 93.1% similar to each other and 86.7–91.4% identical to genomes of other AvCoVs. All five non-spike genes of the two isolates phylogenetically cluster together and distinctly from other IBVs and turkey coronaviruses (TCoVs), including the indigenous African GI-26 viruses, suggesting a common origin of the genome backbone of the Kenyan isolates. However, isolate A376/17 contains a TCoV-like spike (S) protein coding sequence and is most similar to Asian TCoVs (84.5–85.1%) compared to other TCoVs (75.6–78.5%), whereas isolate A374/17 contains an S1 gene sequence most similar to the globally distributed lineage GI-16 (78.4–79.5%) and the Middle Eastern lineage GI-23 (79.8–80.2%) viruses. Unanswered questions include the actual origin of the Kenyan AvCoVs, the potential pathobiological significance of their genetic variations, whether they have indeed established themselves as independent variants and subsequently spread within Kenya and to the neighboring east/central African countries that have porous live poultry trade borders, and whether the live-attenuated Mass-type (lineage GI-1)-based vaccines currently used in Kenya and most of the African countries provide protection against these genetically divergent field variants.The avian gamma-coronavirus infectious bronchitis virus (AvCoV, IBV;  Coronaviridae family) that causes upper respiratory tract, enteric, renal, and reproductive disease  in domestic fowl and is associated with severe economic losses in the domestic poultry industry globally -3′UTR . Six CDSThe complete genome sequences of A374 and A376 showed 87.2% nucleotide identity to each other, or 93.1% identity when the S gene is excluded. Comparative pairwise homologies of the CDS across the genomes of the two Kenyan AvCoVs showed that complete S-genes have the lowest identities , whereas the highest identities are in M (96.4% for both nucleotide and amino acid levels) and 4b  . RegardiBased on the S1 gene, the two Kenyan IBVs identified here do not phylogenetically group with any of the IBVs in lineages GI–GVIII or the UVs ; rather,pro), nsp7 (RNA-dependent RNA polymerase (RdRp) holoenzyme), nsp9 , nsp11/12 (RdRp), and nsp13 (helicase)) and the accessory gene 5 (5b), and the lowest homology in 6b  and the Middle Eastern lineage GI-23 . Conversely, the S protein CDS and S1 gene of isolate A376/17 are most similar to Chinese TCoVs  compared to other TCoVs . In the non-spike genomic regions, the Kenyan AvCoVs share the highest homologies in five of the 16 nsps in gene 1 , domainR-L-R-R↓S, which is located within a 20 amino acid residue region required for cleavage and fusion efficiency [P-S-S-P-T-G-R↓S) has a mutation of the conserved R/K acid residue (consensus motif in IBVs is P-X-S-P-[R/K]-X-R↓S). The membrane fusion peptide of A374/17 has all four residues (CTAGPLGFVKDLVC), which are conserved in CoVs -3′UTR) and size (~27.6 kb) of the two Kenyan isolates are as expected of AvCoVs with canonically conserved essential genes ,62, theyThe current IBV classification is predicated on the S1 gene being the most variable and immunogenic (epitomic) genomic region, and the most commonly sequenced , but theThe higher nucleotide identity among the two Kenyan isolates in the non-spike genomic regions (93.1%) and the phylogenetic grouping together of all five viral genes except the S-gene suggest that their genomic backbones have a common origin. These Kenyan isolates are closest to but group distinctly from the Middle Eastern IBVs (isolate A374/17) and Asian TCoVs (isolate A376/17) and are distantly related to the indigenously African GI-26 viruses , suggesTogether, data from the current study raise questions about the actual origin and evolution of the Kenyan AvCoVs, whether they are also circulating in commercial poultry flocks, and whether migratory wild birds and other non-domestic avian species frequently found scavenging together with rural backyard poultry play roles in the evolution and dissemination of the variants. From our sequence and phylogenetic analyses, the two Kenyan isolates are more similar to each other than to any other sequenced AvCoV sequences over the majority of the genomic backbone, suggesting a shared evolutionary history, and lack of similarities to other sequenced full-length AvCoVs. The S-protein coding sequence of isolate A376 appears to be of recombinant origin similar to but distinct from other sequenced TCoVs such as the Asian and North American TCoVs , and only distantly related to other IBVs. This is a known phenomenon, in which the majority of TCoVs originate from a recombination of an IBV backbone with an S-gene fragment of often unknown origin ,52,66. T® BI L  and CEVAC® Corymune 7K . However, even with the availability of these vaccines, vaccination rates are low outside commercial poultry farming, which is an issue of concern because ~80% of the Kenyan poultry are under non-commercial settings . Some commercial farmers also tend to consult private veterinarians for vaccine options other than the government-approved ones. Based on the phylogenetic and sequence analyses presented in this study, the two Kenyan UVs presented in this study are clearly genetically different from the GI-1-based vaccine strains, which are currently used in Kenya and other African countries. A lack of evidence as to whether the Kenyan UVs cause clinical disease makes it necessary to review the protection of the Mass-type vaccines used in Kenya, because there is evidence that variations of as little as 5% in the S1 gene sequence can negatively affect vaccine efficacy [In most African countries, live-attenuated and inactivated Mass-type-based vaccines are the main control method . Kenya hefficacy .We have reported for the first time in Kenya and the Eastern Africa region the presence of AvCoVs in backyard chickens. Our analyses have demonstrated that the two Kenyan AvCoVs are UVs that are distinct from each other but likely share a common origin not yet represented in the literature, and they do not group with any of the genotypes or strains belonging to the established lineages or other UVs. It is yet to be elucidated whether the genomic variations of the two Kenyan AvCoVs when compared to other previously reported strains are of any pathobiological significance. Outstanding questions include the actual origin of the Kenyan AvCoVs; whether they have indeed established themselves as independent variants in the eastern county of Machakos; and, if so, to what extent they may have spread to the rest of the country and the neighboring east African countries that have porous borders in terms of trade of live poultry. Nevertheless, data from this study underscore the need for active surveillance, identification, and characterization of the variants that are evolving and circulating in the country and the region, because effective vaccination against novel variants requires tailor-made vaccines.


Neuronal intranuclear inclusion disease (NIID) is a rare chronic progressive neurodegenerative disease, with complex and diverse clinical manifestations and pathological eosinophilic hyaline intranuclear inclusions in the central and peripheral nervous systems and visceral organs. Improvements in diagnostic methods such as skin biopsy and gene testing are helpful in revealing the clinical and genetic characters of NIID.NOTCH2NLC gene testing and skin biopsy. Diffusion weighted imaging (DWI) showed high linear intensity in corticomedullary junction. We also reviewed all the published NIID cases with positive NOTCH2NLC GGC repeat expansion and skin biopsy results in PubMed.We presented two cases of NIID diagnosed by using Patient 1 was a 63-year-old male who carried 148 GGC repeats and presented with progressive tremor and limb weakness. Patient 2 was a 62-year-old woman who carried 131 GGC repeats and presented with tremors, memory loss and headaches. The most common clinical manifestation of 63 NIID patients in this study was cognitive impairment, followed by tremors. In our study, almost all the patients were from East Asia, the male to female ratio was 1:1.26, with an age of onset of 54.12 ± 14.12 years, and an age of diagnosis of 60.03 ± 12.21 years. Symmetrical high signal intensity at the corticomedullary junction on DWI were revealed in 80.96% of the patients. For the GGC repeat numbers, the majority of GGC repeats were in the 80–119 intervals, with few GGC repeats above 160. The number of GGC repetitions was significantly higher in patients presented with muscle weakness than in other clinical manifestations.NIID is a neurodegenerative disease caused by aberrant polyglycine (polyG) protein aggregation. NIID mostly occurs in the elderly population in East Asia, with cognitive dysfunction as the most common symptom. Staging NIID based on clinical presentation is inappropriate because most patients with NIID have overlapping symptoms. In our study, there was no significant correlation between the number of GGC repeats and different phenotypes except for muscle weakness. Abnormal trinucleotides repeat and PolyG protein aggregation maybe common pathogenic mechanism in neurodegenerative diseases and cerebrovascular diseases, which needs to be confirmed by more studies. NOTCH2NLC gene  is a rare chronic progressive neuro degenerative disease, with complex and diverse clinical manifestations and pathological eosinophilic hyaline intranuclear inclusions in the central and peripheral nervous systems, and multiple visceral organs. Before skin biopsy was used to diagnose NIID in 2011, less than 40 cases of NIID had been reported . With thNLC gene , more spNLC gene . In patiNLC gene , retinopNLC gene , recurreNLC gene , miosis,NLC gene , can alsAccording to the age of onset, NIID can be divided into three subgroups: infant form, juvenile form, and adult form . SporadiDespite the gradual increase in the reported cases of NIID, the pathogenesis, and the correlation between NIID genotype and phenotype remain unclear. Currently, there are lack of large sample size clinical studies analyzing the clinical characteristics of patients with NIID. The purpose of this study was to report two typical adult cases with NIID diagnosed with both genetic and pathological studies and to summarize and analyze the clinical, genetic, pathological, and radiological characteristics of all the reported NIID patients diagnosed with the same criteria.NOTCH2NLC gene and skin biopsy, with DWI showing high intensity in corticomedullary junction. We also reviewed all the cases of NIID in PubMed database searching by using the terms “neuronal intranuclear inclusion disease.” Case reports and references were obtained and reviewed. The inclusion criteria were as follows: (1) skin biopsy indicating intranuclear inclusions in the nuclei of fibroblasts, fat cells and ductal epithelial cells of sweat glands, (2) NOTCH2NLC gene testing showing abnormal repeated GGC premutation, and (3) detailed medical history. Finally, 63 patients met the inclusion criteria  and/or Mini-Mental State Examination (MMSE) evaluations were conducted for screening cognitive impairment. The patients subsequently underwent lumbar puncture, electromyography (EMG), and electroencephalography (EEG). All patients provided their written informed consent to participate in this study. The Local Ethics Committee of The Sixth Medical Center of the PLA General Hospitals approved this study.Two NIID-affected case subjects from mainland China were included for this study. Both of them were recruited from our hospital. All NIID-affected case subjects presented with typical high linear signals in corticomedullary junction in DWI and received skin biopsy and 1-weighted spin echo images (T1WI), T2-weighted spin echo images (T2WI), fluid attenuation inversion recovery (FLAIR) images, and DWI images were performed on a standard clinical 3.0-T MRI scanner.All MRI examinations including conventional TUnder local anesthesia, a 5 mm diameter skin biopsy specimen was obtained from 10 cm above the lateral malleolus of the affected individual. Histochemical samples were fixed in 10% formalin, embedded in paraffin, and sliced into 6 mm-thickness sections. The sections subsequently were stained with Hematoxylin and Eosin (H&E), and anti-p62 antibody immunofluorescence. Samples for electron microscopic were fixed with 2.5% glutaraldehyde, then incubated in 1% osmium tetroxide, followed by dehydrated with graded acetone, and finally embedded with resin. After stained with uranyl acetate and lead citrate, ultrathin sections were viewed with electron microscopy.NOTCH2NLC gene. GC-rich PCR (GC-PCR) was performed to evaluate the number of GGC repeats.For the repeat-primed PCR (RP-PCR) assay, a fluorescein labeled gene-specific primer were utilized for identifying the GGC repeat expansion of NOTCH2NLC gene showed that the number of GGC repeat amplifications was 148  and 5.98 ng/ml  respectively. The lumbar puncture pressure, routine CSF analysis and CSF cytology showed no abnormalities. Serum and CSF were negative for oligoclonal band and myelin basic protein. The electrocardiogram (ECG) and EEG were normal. EMG results of peripheral nerve suggested slowed motor and sensory nerve conduction, suggesting nerve myelin sheath damage. No significant abnormalities on ultrasound of the chest and abdominal organs. Both cerebral atrophy and leukoencephalopathy were observed by brain MRI . Brain M was 148 . Immunof was 148 . Based o1 and high T2/FLAIR signals  score of 10, suggesting a manic episode. The Geriatric Depression Scale (GDS) score was 14, suggesting mild depression. The Self-Rating Anxiety Scale (SAS) was 38, suggesting moderate anxiety. Apart from the positive pyramidal sign, no significant abnormalities were found on neurological examination. The lumbar puncture pressure, CSF chemical analysis and cytology were normal. Laboratory examinations, routine blood tests and biochemical tests were unremarkable. Serum and CSF were negative for oligoclonal band and myelin basic protein. A total of 24 h ECG suggested inferior wall myocardial ischemia, and the coronary CTA indicated mild stenosis of the right coronary artery. Ultrasonography of chest and abdomen organs showed no obvious abnormality. Peripheral nerve EMG did not show abnormalities. Digital video electroencephalogram revealed some diffuse slow waves, especially in the leads of frontal and temporal regions. Brain MRI-DWI showed corticomedullary junction hyperintensity, especially in the parietal and frontal lobes . Bilater signals , no enha signals . We perf signals . A saw-t signals . A totalh GC-PCR . Finallyn = 16) and an MMSE score of 20.54 ± 8.85 (n = 26). Tremor  and other Parkinsonian symptoms are not uncommon. Bladder dysfunction is the most common autonomic dysfunction symptom. Some patients also showed signs of peripheral nerve damage such as muscle weakness and sensory deficits, and EMG suggested damage to motor and sensory nerves. A total of 21 patients presented with other neurological deficits such as impaired consciousness, mainly due to encephalitis attacks. Fifty-two of the 63 patients showed high signal in the corticomedullary junction region on DWI. In addition, cerebral white matter lesions and cerebral atrophy were also common, and a small number of patients with encephalitis also showed abnormal contrast enhanced lesions. Of the 26 patients who underwent lumbar puncture, elevated protein concentrations in the CSF were found in 21 cases. The NOTCH2NLC gene testing in 53 patients showed GGC repeat number of 102.98 ± 23.52. Among all diagnosed patients, 80–99 and 100–119 were the most common GGC repeat number intervals for NIID  of NIID patients showed abnormal DWI signals, which is related to lesions in the brains of NIID, while there is small percentage of patients with NIID who do not exhibit abnormalities on DWI and are misdiagnosed. The highly diverse clinical presentations of NIID poses difficulties in clinical diagnosis. Combining gene testing and pathological studying for diagnosis can improve the diagnostic reliability of NIID.In this study, we report two classical NIID patients diagnosed genetically and pathologically, and we also reviewed all NIID patients diagnosed with the same criteria, and summarized the clinical features of 63 patients with NIID. We found that patients with NIID diagnosed with the abnormal NOTCH2NLC gene leading to intranuclear inclusion body invasion into different tissues and cells of the nervous system and other systems. Since all the nervous system  may be affected, and the clinical manifestations depend on the site involved, the clinical presentation vary widely. Although NIID has previously been proposed to be classified into different subtypes based on different symptoms , a concept that refers to all diseases with the GGC repeat expansion in the 5′UTR of NOTCH2NLC gene. To date, NRED includes Parkinsonism-related disorders   , and it isorders . Aberranneration .NOTCH2NLC gene are associated with sporadic cerebral small vessel disease  for the publication of any potentially identifiable images or data included in this article.BZ designed and wrote the manuscript. MY and QY contributed to the conception and carried out a logic examination of the manuscript. ZW, YZ, and SP participated in the review of medical professional knowledge of the manuscript. MY, QY, and BZ helped with proofreading and revision. YY and XQ contributed to the conception and critically revised the manuscript. All authors contributed to the article and approved the final version.


Machine learning can be used to explore the complex multifactorial patterns underlying postsurgical graft detachment after endothelial corneal transplantation surgery and to evaluate the marginal effect of various practice pattern modulations. We included all posterior lamellar keratoplasty procedures recorded in the Dutch Cornea Transplant Registry from 2015 through 2018 and collected the center-specific practice patterns using a questionnaire. All available data regarding the donor, recipient, surgery, and practice pattern, were coded into 91 factors that might be associated with the occurrence of a graft detachment. In this research, we used three machine learning methods; a regularized logistic regression (lasso), classification tree analysis (CTA), and random forest classification (RFC), to select the most predictive subset of variables for graft detachment. A total of 3647 transplants were included in our analysis and the overall prevalence of graft detachment was 9.9%. In an independent test set the area under the curve for the lasso, CTA, and RFC was 0.70, 0.65, and 0.72, respectively. Identified risk factors included: a Descemet membrane endothelial keratoplasty procedure, prior graft failure, and the use of sulfur hexafluoride gas. Factors with a reduced risk included: performing combined procedures, using pre-cut donor tissue, and a pre-operative laser iridotomy. These results can help surgeons to review their practice patterns and generate hypotheses for empirical research regarding the origins of graft detachments. Two principal treatment modalities are currently used, namely Descemet’s stripping endothelial keratoplasty (DSEK) and Descemet’s membrane endothelial keratoplasty (DMEK)2. In recent years, DMEK has increased in popularity due to its potential for faster visual recovery and improved visual outcome compared to DSEK4. In both DSEK and DMEK, postoperative detachment of the graft is a relatively common complication7. Detachment can require a secondary surgical intervention, potentially resulting in a less viable graft. The reported prevalence of graft detachment ranges from 2 to 27% for DSEK and 6% to 82% for DMEK7.Posterior lamellar keratoplasty is the current standard treatment to restore visual function in patients with irreversible corneal endothelial cell dysfunction12, and a wide range of risk factors have been proposed and/or investigated relating to the type of procedure (DSEK versus DMEK)7, graft storage and preparation 16, and recipient and donor’s characteristics 18. Furthermore, various “best practice patterns” have been proposed, resulting in a wide range of surgical tools and techniques that have been adopted when performing posterior lamellar keratoplasty19. These include the insertion method21, the size of the descemetorhexis23, combined surgical procedures27, the use of anterior chamber (AC) tamponade 33, and the duration of time spent in the supine position (imposed or recommended) following surgery28.The underlying cause of graft detachment is considered to be multifactorialIn the Netherlands, all centers that perform corneal transplants report their procedures to the Netherlands Organ Transplant Registry (NOTR). These records include extensive follow-up data, including complications, thus providing a unique source of real-world data regarding graft survival, patient characteristics, and donor characteristics. We expanded this dataset using a 35-item questionnaire regarding the preoperative, perioperative, and postoperative procedures performed at each center, as rapidly changing practice patterns in the field of surgery made performing an independent assessment of these practice patterns in a clinical study unfeasible.35. Here, we present the results of our machine learning analysis to identify factors that predict an increase or decrease in the risk of graft detachment following posterior lamellar keratoplasty.Machine learning models can be used to detect complex patterns in large datasets, and these patterns can help researchers identify factors that can predict the risk of postsurgical complicationsA total of 3647 posterior lamellar keratoplasties were performed in the Netherlands and recorded in the NOTR registry between January 1, 2015 and December 31, 2018, including 2651 DSEK procedures (73%) and 996 DMEK procedures (27%). The surgeries were performed at sixteen centers throughout the Netherlands. Twelve of these centers submitted their practice patterns (Supplementary Tables The mean (± SD) donor age was 70 ± 9 years, and 61.4% of donors were male. The most common cause of death was diseases of the circulatory system (53.3%), followed by diseases of the respiratory system (16%), other/unknown (20.3%), cancer (8.8%), and trauma (1.5%). The mean interval between death and the transplant procedure was 19 ± 5 days. A complete summary of the donor characteristics is provided in Supplementary Table The most common indication for surgery was FECD (76.7% of cases). Interestingly, FECD was the indication for performing DMEK in 91.1% of cases, compared to 71.2% in DSEK. The majority of recipients were pseudophakic prior to surgery, with 62.3% having a posterior chamber intraocular lens. In total, 88.8% of recipients had not previously undergone a corneal transplant in the same eye. In 39.5% of cases, the graft was equal in size to the descemetorhexis; the graft was undersized in 26.1% of cases and oversized in 34.4% of cases. In 71.7% of cases, posterior lamellar keratoplasty was not combined with another surgical procedure. The most frequently performed combined surgical procedures were peripheral iridectomy and cataract surgery . A surgical complication was reported in the NOTR in 4.1% of all cases (3.3% of DSEK procedures and 6% of DMEK procedures) and included endothelial damage (0.8% of cases), difficulty unfolding the graft (0.7%), graft rupture or preparation problems (0.4%), iris prolapse (0.4%), and hemorrhage of the AC (0.4%). The recipient and surgery characteristics are summarized in Supplementary Tables The incidence and prevalence of postoperative graft detachment are summarized in Table After correction for the DMEK learning curve, a total of 3464 cases were included for machine learning analysis. The discriminatory power of the three machine learning models at predicting graft detachment (based on the AUC) ranged from 0.65 to 0.72 . Our identification of predictive factors can help surgeons make evidence-based changes of their practice patterns, provide insight in the marginal contribution to surgical safety of current practices, and can help generate hypotheses for empirical clinical research regarding the origins of graft detachments. Particularly, this study can function as a data-driven protocol standardization of future prospective studies regarding posterior lamellar keratoplasties.36. Moreover, the presented approach enables the evaluation of the numerous modulations of practice patterns in use and the relative impact of proposed key factors, particularly of value in the rapidly evolving field of surgery in which assessing these practice patterns independently in a clinical study would not be feasible.A major strength of this study is our access to an extensive, nationwide dataset and the inclusion of practice patterns in our analysis of a national cornea transplantation registry. The real-world data of the transplantation registry are represented with practically absent inclusion bias, owing to the obligatory and incentivized data-entry in the register. The assessment of both linear and non-linear relationships between a wide range of factors is unique and revealed the complex interactions between factorsDespite these strengths several limitations warrant discussion. None of our three models explain all of the variance in our dataset, and not all factors that can affect graft detachment are registered in our dataset . Furthermore, the register lacks comprehensive contextual information and the completeness and correctness of the data in the registry could not be validated. This lack of contextual information is exemplified by our finding of unknown and/or missing observations in the model output; the interpretation of which is ambiguous and full of assumptions. We therefore chose to not report these outputs. With respect to the practice patterns, we cannot exclude response/recall bias regarding the replies to the questionnaire. Although the surgical protocols for DSEK and DMEK overlap to a large degree, they also differ in several respects. By aggregating the two procedures into a single database, procedure-specific predictive factors might not be identified. Certain predictive factors, such as aphakia, were relatively rare and therefore lack the necessary power to appear in the model output, whilst experts agree on the added risk of this particular condition. Therefore, the effect of certain variables cannot be estimated reliably. Finally, the retrospective nature of the study should be noted. Prospective validation of the results is essential to evaluate the usefulness of the models and possible applications in clinical practice.37, and our results indicate that DMEK is associated with an increased risk of graft detachment, consistent with previous studies6. This increased risk may be due in part to increased difficulty when handling the DMEK graft and/or the fact the DMEK graft edge is more prone to curling up, thus lifting the graft from the recipient’s stromal bed39. In addition, partial detachments are more common after DMEK, possibly increasing the rate of rebubbling of the graft compared to DSEK40. Alternatively, the increased risk associated with DMEK may partially be related to the surgeon’s learning curve. Indeed, from 2016 to 2018 the prevalence of graft detachment decreased more steeply for DMEK than for DSEK4. In our model, we attempted to correct for this learning curve by excluding the first 20 DMEK surgeries performed at each clinic, although the results in Table The effect of donor-related factors, recipient-related factors, surgery-related factors, and practice patterns on the prevalence of graft detachment is an ongoing topic of discussion. Many surgeons in the Netherlands are transitioning from DSEK to DMEK15. Graft marking was associated with an increased risk of detachment in the Lasso model only. However, in the Netherlands graft marking is infrequently practiced, clouding the full assessment of the effect of this practice. Furthermore, and consistent with previous findings, our models indicate that patients who had one or more previously failed grafts had a higher risk of detachment36.Our results show a diffuse pattern of donor age, recipient age, donor cause of death, and the interval between donor death and surgery. Regarding these factors, our analyses are inconclusive. Regarding preparation techniques, our results are consistent with previous studies that found no difference between pre-cut and surgeon-cut tissues21. Furthermore, we found that a graft diameter > 8.4 mm may be associated with a reduced risk of graft detachment. Several groups previously hypothesized that a larger graft may overlap with the retained Descemet membrane in the recipient, thus inhibiting graft attachment23. However, no effect of graft size compared to the descemetorhexis size was found. Both DMEK and DSEK are increasingly combined with other procedures such as cataract surgery. In none of our models a combination of procedures was associated with an increased risk risk of graft detachment. Combining these results with previous studies we can conclude that combining surgical procedures does not increase the risk of graft detachment26. Finally, two of the three models in our study found that pre-operative laser peripheral iridotomy was more protective than surgical peripheral iridectomy, although none of the models found that surgical peripheral iridectomy substantially increased the risk of detachment. This difference between laser iridotomy and surgical iridectomy may be due to the increased risk of intraoperative fibrin formation during surgical iridectomy41.We also found that several types of graft insertion devices were associated with an increased risk graft detachment; however, we consider the choice of insertion device a proxy for idiosyncratic surgeon factors too subtle to be captured in our register or questionnaire. We opted not to enter to individual surgeon or center as a model factor, as this study is not designed as an exercise in benchmarking. Notwithstanding, these expected between-surgeon differences might now be attributed to proxy parameters. The insertion tools themselves are known to increase the risk of endothelial damage, although no significant differences have been found between the various commercially available insertion devices43. This discrepancy may be explained in part by the recent transition of surgeons to using SF6 gas together with the concomitant transition to performing DMEK (with a subsequent increased risk of detachment in their learning curve). Nevertheless, we believe that the previously reported putative benefits associated with using SF6 gas might have been overestimated relative to all other factors and is exemplified by continued reports of relatively high rates of graft detachment45. After posterior lamellar keratoplasties, patients are instructed to remain in the supine position in order to maximize the beneficial effects of AC tamponade, and the length of time in this position can affect the risk of graft detachment. The results of our study indicate that strictly imposing a supine duration of at least 2 h reduced the risk of graft detachment. Similar results were also found if the patients were instructed to remain in the supine position for 48 h following surgery, consistent with the routine practice of most surgeons28.Interestingly, we found that using air as the tamponade agent was not associated with an increased risk of graft detachment, while using SF6 gas appeared to increase the risk of graft detachment. This finding is in contrast with previous studies suggesting that the use of SF6 gas may reduce the risk of graft detachment47. Similarly, we found no increased risk of complications either during or following surgery; however, this apparent lack of effect may have been due to the relatively low incidence of these events.Lastly, several previously suggested risk and protective factors were not identified by our models. For example, we found no effect of increasing intraocular pressure above physiological limits for a certain time, consistent with previous studies suggesting that overpressuring of the eye after graft insertion has only a limited protective effectIn conclusion, we applied a supervised machine learning approach to a nationwide dataset and identified the most relevant factors for predicting graft detachment following posterior lamellar keratoplasties. Our analysis revealed that performing a DMEK procedure, the use of SF6 gas, and previous graft failure increased the risk of detachment, whereas performing a DSEK procedure, preoperative laser iridotomy, larger graft size, remaining strictly supine for at least 2 h, and a recommendation for staying in the supine position for 48 h reduced the risk of detachment. In contrast, performing a combined procedures and the use of pre-cut tissue had no effect on the risk of graft detachment, neither did overpressuring of the eye after graft-insertion. These results can help surgeons improve their practice patterns and can help researchers formulate new, testable hypotheses. Future studies should focus on improving the performance of machine learning approaches by including more detailed, contextual information. Importantly, these models’ “in silico” predictions should be tested in clinical practice.The data used in this study were acquired from the NOTR, which is hosted by the Netherlands Transplant Foundation (NTS). We included all DSEK and DMEK procedures registered in the NOTR between January 1, 2015, and December 31, 2018, including 12 months of follow-up data. The Netherlands Institute for innovative ocular surgery did not participate in the nationwide registry at the time of the data collection (2015–2018) and their data is therefore not included in this analysis. Two cornea banks  supplied all of the corneal grafts assessed in this study. The NOTR steering committee provided Institutional Review Board (IRB) approval for the extraction and analysis of data in this study. All patients provided informed consent to be included in the registry for research purposes. No identifying information of donors or patients was available to the researchers and all data were anonymized prior to delivery to the researchers. No donor tissue was were procured from prisoners. In accordance with IRB approval, the data were not stratified at the individual surgeon, center, donor or patient level. The study was conducted in accordance with the principles of the Declaration of Helsinki and Dutch legislation. The NOTR data were restructured and made accessible for machine learning analysis.All available data in the registry regarding the donor, graft, recipient, and practice patterns was collected. The donor’s information included sex, age at the time of death, cause of death, endothelial cell count, interval between death and explantation of the eye, interval between explantation of the eye and preservation of the eye, and interval between death and the transplant procedure. The donor’s cause of death was classified into the following five categories: neoplasms/cancer, diseases of the respiratory system, trauma, diseases of the cardiovascular system, and other causes of death. The recipient’s information included sex, age at the time of surgery, indication for corneal transplantation surgery, and preoperative lens status. The indication for transplant surgery was classified into the following five categories: Fuchs corneal endothelial dystrophy (FECD), pseudophakic bullous keratopathy (PKB), graft failure, other corneal dystrophies, and other indications. Information regarding the surgical procedure included the surgeon’s position , date of surgery, instruments used for donor preparation, instruments used for graft insertion, diameter of the donor graft, diameter of the descemetorhexis, whether it was a combined surgical procedure, and surgical complications. Combined surgical procedures were recoded into the following five groups: peripheral surgical iridectomy, cataract surgery, posterior intraocular lens insertion without cataract extraction, anterior vitrectomy, and other combined surgical procedures or unspecified. Postoperative events recorded in the NOTR were classified as surgery-related  and not surgery-related . The recoding of the variables resulted in a set of 91 predictor variables.We used a questionnaire to determine the practice patterns used by the transplantation centers that contributed their data to the registry, including the center-specific practice patterns  and any protocol changes that may have occurred within the data collection period. All practice patterns questionnaires were collected by the NTS and anonymized before delivery to the researchers.4.The center-specific practice patterns were connected to the respective patients in the registry, and protocol changes that occurred in the period between January 2015 and December 2018 were taken into account. To reduce the potential effects of a surgical learning curve, the first 20 DMEK surgeries performed at each center were removed from the datasetThe primary outcome measure of this study was postoperative graft detachment, which was defined as the occurrence of an intervention to re-adhere the graft  reported in the NOTR. The dataset was divided into a training set and a test set, compromised of 70% and 30% of the dataset, respectively. The training set was used to develop a suitable model based on the predictive variables identified, and the test set was used to validate the model. The following three machine learning models were built: a L1 regularized logistic regression using least absolute shrinkage and selection operator (lasso) model, a classification tree algorithm (CTA), and random forest classification (RFC).48. For each split, the explanatory variable that best partitioned the records was chosen based on accuracy, until the set could not be split further. To reduce over-fitting, pruning was performed using fivefold cross-validation, thus removing nodes that did not improve the accuracy of the tree. In the final tree, each leaf node was assigned the class with the highest frequency among its records, and each record reaching the node was predicted as being in that class. Although classification trees are very useful to detect higher-order relations and non-linear relations, they are not very robust, meaning that small changes in the data can result in large changes in the final estimated tree. RFC leads to a more robust classification model by building a large number of classification trees and splitting the data using a random sample of the entire set of explanatory variables to serve as split candidates. The resulting trees were combined by taking a majority vote, and the overall prediction was the most frequently occurring class among all predictions. By forcing each split to consider only a subset of variables, the RFC analysis overcomes the potential problem of one or more strong predictors dominating the solution, thus rendering the average of the trees less variable and therefore more reliable. In this study 1000 trees were used to build the RFC model.These three models have been chosen for the following reasons. Given the 91 predictors, a simple logistic regression analysis with outcome graft detachment is computationally difficult or even impossible. The lasso model is a special form of logistic regression in which the estimated regression coefficients are shrunken towards zero relative to the least squares estimates. As a result, some coefficients will be exactly zero, which leads to the selection of a subset of most predictive predictors for graft detachment. However, the Lasso will only be able to detect linear relations of the predictors with the outcome detachment. To detect non-linear relationships and higher-order relationships among the explanatory variables, we used CTA and RFC. The CTA partitioned the training dataset based on outcome  using a series of successive splits 49. The RFC model was trained in combination with weights to balance the outcome classes. No resampling techniques were used for the test set.The relatively low rate of graft detachment in the dataset resulted in a large imbalance between the two outcome categories  and can therefore affect the statistical model estimation and evaluation. To solve this imbalance, we performed random oversampling of examples (ROSE) for the lasso and the CTAWe summarized all quantitative and qualitative variables, including the donor characteristics, recipient characteristics, procedure characteristics, postoperative events, and practice patterns. The prevalence of graft detachment was determined separately for all procedures involving DSEK and all procedures involving DMEK independently. All statistical analyses were performed using the R statistical software package version 4.0.5 , except for the RFC which was performed using in Python version 3.8 and the scikit-learn package version 0.24.1 .The machine learning models were evaluated using the test set. The predicted outcome was compared with the observed outcome reported in the NOTR  by calculating the sensitivity, specificity, and the area under the curve (AUC). As different machine learning methods were used it was expected the models would diverge to some extend and a qualitative analysis of the model outcomes was performed. The overlap between models was used to identify factors associated with an increased or decreased risk.Supplementary Information 1.Supplementary Information 2.Supplementary Information 3.Supplementary Information 4.Supplementary Information 5.Supplementary Information 6.Supplementary Information 7.


This paper presents a new method, a fast prediction method based on the Cartesian stiffness model and equivalent spring stiffness (FPM-CSES), to calculate displacement errors of deformation caused by low stiffness for industrial robot. First, the Cartesian stiffness model based on the Jacobian matrix was established for a robot, and then the displacement error model of deformations caused by external force was established based on Cartesian stiffness. Second, the transmission system of the robot’s joint was analyzed, and an equivalent method for joint stiffness was presented based on a series spring system. Meanwhile, the stiffness of the key components including the servo motor, harmonic reducer, and timing belt was deduced in detail. Finally, a compared simulation and a measurement experiment were conducted on a 6-joint series robot. It was found that the FPM-CSES could calculate any configuration among the robot’s workspace. Compared with the finite element analysis (FEA) method, the presented method is feasible and more efficient. The experimental results showed that the prediction accuracy of the FPM-CSES is rather high, with an average rate of more than 83.72%. Hence, the prediction method presented in this study is simple, fast, and reliable, and could be used to predict and analyze the displacement errors caused by the cutting force, and provide the basis for trajectory planning and error compensation, enhancing the robot’s machining performance. With the higher demands of manufacturing automation and intelligence, industrial robots (IRs) are developing rapidly, and the application of IR is becoming more and more mature such as in welding, spraying, and carrying, and so on. Compared with traditional CNC machine tools, IRs have the advantages of large workspace, higher flexibility, and lower cost ,2,3. HowThere are two main sources of elastic deformation of IRs: one is the elastic deformation of the joints, and the other is the elastic deformation of the links. Among the existing research, the calculation methods of robot stiffness are mainly divided into two types. One is considering both the stiffness of the joints and links. Generally, the finite element method and the hypothetical modal method are used for the analysis of the flexibility of the links. Yang and Sadler  proposedAt present, the relationship modeling between the joint stiffness and the robot’s end effector (EE) is established mainly through the two approaches: the theoretical assumed model and the experimental measurement method. Generally, the series springs are assumed for the joints in the theoretical model , and fraThere are various measurement and identification methods for joint stiffness and the whole stiffness of the robot’s EE ,18. ZhanTo date, however, the displacement errors due to stiffness for IRs have not yet been sufficiently investigated. Many of the methods available are based on field measurements with the help of additional measuring instruments, which are time-consuming and costly, and even require professional operations. Some others are based on the mathematical model, but usually involve a complicated derivation process.Recently, one of the most promising concepts for quality control and improvement is called zero defect manufacturing (ZDM) ,22 that Considering that serial robots with six degrees of freedom (six DoFs) are one of the most widely IRs in today’s manufacturing industry, this paper will focus on the prediction method of displacement errors caused by low stiffness for IRs. The rest of this paper is organized as follows. In this paper, the D-H parameter method was adopted for kinematic modeling. For each link of the robot, there are four kinematic parameters based on the D-H method including link length To explain the modeling method, a 6-joint serial robot—IRB 120—was used as an example. First, the coordinated system of the robot was established, as shown in The overall transformation matrix i} with respect to the base coordinate system.The relationship between the velocity of the robot’s EE and the joint velocity can be described byFor IRs, the robot’s stiffness refers to the ability of the robot to resist deformation after the end flange of the robot receives the force and moment. Assume that the external six-dimensional wrench vector The displacement error caused by deformation can be expressed byThe relationship between the external wrench vector and displacement error can be expressed as:From the aspect of the mechanical structure, a joint consists of transmission components such as gears, chains, belts, shafts, etc. Assume that the torque received by each joint of the robot is denoted by The relationship between the Cartesian stiffness matrix of the robot’s EE and the joint stiffness  can be ds matrix :(13)KC=[The influence of urations . Neverth ignored , and EquAccording to Equations (9) and (14), the displacement error model of the deformation caused by external force and moment can be established as follows:It can be seen that when the robot’s EE is applied a certain force and moment, the displacement errors caused by the robot’s low stiffness can be predicted, as long as we know the Jacobian matrix and joint stiffness. The Jacobian matrix, which is posture dependent, can be obtained according to Equations (4)–(6). Thus, how to calculate the joint stiffness of a robot will be introduced below.Generally, the transmission system of a robot’s joint includes the servo motor, reducer, timing belts, etc. Therefore, the stiffness calculation methods of the typical mechanical components can be deduced based on empirical formulas.The natural frequency of the AC servo motor system can be obtained based on the torsional vibration model. The natural frequency Therefore, as long as the mechanical time constant of the motor and the moment of inertia of the rotor are known, the torsional stiffness of the motor can be obtained.There are two main approaches to measuring the stiffness value of the harmonic reducer. One is to fix the input shaft, then apply torque at the output shaft from zero to the rated torque Generally, the stiffness of the output end is regarded as the standard value of the torsional stiffness of the reducer. The torsional stiffness can be calculated byThe torsional stiffness of the timing belt is divided into two parts: one is the tensile stiffness of the timing belt, and the other is the torsional stiffness of the pulley. The stiffness calculation formula of the timing belt can be expressed asSince each joint of a series robot is independent and controlled by their respective drive systems, the stiffness of each joint can be solved separately. The transmission system of a joint is mainly made up of three components: the driving component, transmission component, and link component. Here, we propose a new method, an equivalent method of stiffness based on the series spring system. Namely, all of the components’ stiffness of joint is converted to the equivalent stiffness of the corresponding joint’s output end. First, the transmission system is equivalent to a series system composed of a number of elastic elements. The conversion principle of the joint stiffness is shown in Compared with the traditional CNC machine tool, IRs have the advantages of large workspace, higher flexibility, and lower cost. However, the low stiffness characteristic of industrial robots limit their application in the field of precision manufacturing. Therefore, we proposed a new method, a prediction method based on the Cartesian stiffness model and the equivalent spring stiffness (FPM-CSES), to calculate the displacement errors caused by the low stiffness of IR.In order to verify the feasibility and reliability of the above displacement error model and equivalent method of joint stiffness, the compared simulation and measurement experiments were carried out on a 6-joint series robot, IRB 120. The finite element analysis (FEA) method was adopted as the compared data, and a laser tracker was used to measurement the displacement errors.First, the joint transmission systems of the robot were analyzed, as shown in Second, the joint stiffness parameters were calculated. For the AC servo motors, the mechanical time constant The harmonic reducer of the robot was of the CSG series. According to the product specifications of the reducers, the reduction ratio and stiffness values are shown in The timing belt is a belt with a circular tooth profile of 3GT produced by MISUMI. The tooth form factor To sum up, the joint stiffness values of each joint were calculated according to Equation (21), and the results are shown in To verify the feasibility and reliability of the displacement error model, the compared simulation was conducted based on the FEA method.t1 is the run time of the calculation process based on the displacement error model.First, the displacement errors were predicted based on FPM-CSES. According to Equations (4)–(6) and (15), and Next, the deformations by force were analyzed based on the FEA method adopting ANSYS Workbench. We assumed that the robot links were rigid bodies and only the stiffness of joints was considered. First, the materials of the robot were set up. The main body of the robot was made of cast iron. The density of the material was calculated according to the volume of the robot model and the weight of the robot. Second, the connections of the joints were set up. The link pair setup was adopted, and the torsional stiffness of the rotary pair was set according to Comparing To verify the feasibility of the FPM-CSES, a measurement experiment was carried out on a 6-joint series robot, IRB 120. This experiment was to measure the displacement errors caused by forces applied at the center of the robot’s EE, as shown in As shown in Meanwhile, the displacements of the 55 points were measured before and after applied force, respectively. The different values between the two measured values were the displacement errors. The calculation results based on FPM-CSES and the measurement results are shown in Therefore, FPM-CSES could be used to predict and analyze the displacement errors caused by cutting force in advance, and provide the basis for trajectory planning to avoid the low stiffness configuration and enhance the robot’s machining performance. Moreover, it could be used to provide the data support for error compensation. In addition, after careful observation of Compared with the FEA method, it is more efficient to calculate the displacement errors caused by the applied force using FPM-CSES;The displacement errors of any configuration among the robot’s workspace caused by applied force can be quickly predicted;The results showed that the prediction accuracy was rather high, with an average rate of more than 83.73%.IRs have the advantages of large workspace, higher flexibility, and lower cost. Thus, IRs are widely used in welding, spraying, and carrying and so on. However, the low stiffness characteristic of IRs limits their application in the field of precision manufacturing. Therefore, this paper presented a new prediction method, FPM-CSES, to calculate the displacement error caused by low stiffness when the robot’s EE is applied force. The method development was established based on the Cartesian stiffness model and equivalent spring stiffness. The feasibility and reliability of the presented method was verified by simulation and experiments. The results allowed us to arrive at the following major conclusions:It is therefore reasonable to conclude that our FPM-CSES is simple, efficient and reliable, and that it can provide the basis for trajectory planning to avoid low stiffness configurations and provide the data support for error compensation, enhancing the robot’s machining performance and the precision of products. It should be noted that the presented method is an approximate calculation method. To enhance the predicted accuracy, the gravity of the mechanism should be taken into account. In future work, according to ZDM, we intend to focus on the prevention strategy .


Using a 5.5 mm-height ti-base abutment may produce a clinically unacceptable outcome (ΔEab > 2) in A1/0 and A2/3 color groups.The effects of different heights of ti-base abutments on the color of anterior screw-retained zirconia restorations fabricated using computer-aided design and computer-aided manufacturing (CAD-CAM) technologies may affect the optical clinical outcome. The purpose of this study was to measure and compare the color parameters of zirconia crowns in different shades on ti-base abutments. Identical specimens (N = 160) were milled to restore the screw-retained central maxillary incisor crown, using 5% mol yttria zirconia (5Y-TZP). The specimens were designed using computer design software to match 3.5 mm and 5.5-mm ti-base abutments and milled using one CAD-CAM technology. Specimens were divided into four main groups depending on zirconia shade  and then assigned to two subgroups according to ti-base height. Color measurements in the CIELab coordinates were made using a spectrophotometer under room-light conditions. Color difference (ΔE*) values were calculated using the CIE76 and CIEDE2000 formula. Within the group of A0/1 and A2/3, for 5.5 mm abutment height, a significant difference was found between the means of colors ∆E00 and ∆Eab ( An anterior fixed prosthesis aims to mimic nature by providing the same characteristics for natural teeth as texture, size, shape and color properties. Implant-supported restoration can be applied by two different techniques, either a screw-retained prosthesis or a cement-retained prosthesis . The useOne recent study evaluated the effect of ti-base abutment height on the retention of zirconia crowns using a pull-out test and concluded that the ti-base height has no effect on zirconia superstructure retentiveness . HoweverQuantifying tooth color is usually performed via the CIELab system, using the computerized data obtained by a spectrophotometer, which allows for mathematical analysis and comparison of color properties ,9,10. AcPrevious studies have reported a variability in the findings of the color threshold using the CIE76 formula ,9,10, ΔE2O3), minimizing pores sizes, evaluating sintering temperatures and using larger grains can enhance the monolithic zirconia esthetic properties [Few studies, however, have examined the effect of several factors on the light scattering of zirconia, such as material composition, porosity, sintering and grain size, concluding that reducing oxide alumina particles  was screwed to an implant analog  embedded in acrylic resin , then scanned using a laboratory scanner . The 3D digital data was inserted into the computer software  in order to virtually design two identical monolithic screw-retained zirconia implant central incisor crowns to match 3.5 mm and 5.5 mm ti-base abutments . The crown was designed with a facial aspect thickness of 0.8 mm at the ti-base finish line up to 2 mm at the mid-occlusal-gingival crown height and with screw-channel located in the mid-buccal-palatal aspect .The monolithic zirconia crowns were milled from a 5 mol% yttria-stabilized tetragonal zirconia polycrystal (5Y-TZP) block  using CAD-CAM technology  in a dry fine milling strategy. Three cutter tools: 2.5 mm, 1 mm and 0.6 mm, were used. Each set of 3 new cutter tools was for milling 90 specimens. In order to mimic clinical conditions, the crowns were hand polished using diamond polish mint paste  and glazed using a synthetic disc  with porcelain polishing paste  in a single direction for 30 s by the same operator (AB).One hundred and sixty CAD-CAM ti-base abutments with two heights of 3.5 and 5.5-mm  were screwed to resin-embedded implant analogs  .Specimens were divided into 4 main groups depending on zirconia shade, then divided to 2 subgroups according to ti-base height; no cement was used to prevent cement color bias .A digital spectrophotometer  was used for color measurements. For the color measurement, a special mold was used to standardize the specimen’s position, making the spectrophotometer probe tip axis perpendicular to the tested specimen’s buccal surface. The device was calibrated according to the manufacturer’s instructions using a calibration apparatus before each subgroup, and all measurements were made in the optical environment. All the specimens were tested with a standardized-photography neutral 18% gray card  as a background. Room illuminance was 1007 lux, which was measured using a light meter . Specimens were randomized in each group, and the spectrophotometric measurements were performed and recorded by a single operator (ML) with the Commission International de I’Eclairage (CIE) L*a*b* color space system, which allows for the determination of color in the three-dimentional space. L* indicates the lightness (0–100), with 0 being black and 100 being white. The coordinate a* is for red and green, and b* is for yellow and blue.The CIE76 and the CIEDE2000 formulas based on the CIELAB color space are as follows:00 ≤ 1.30 and Δab ≤ 1.00. Clinical acceptability was set at ΔE00 > 2.25 and Δab > 2 [In the present study, the parametric factors of the CIEDE2000 formula were set to 1. Further, the perceptibility threshold was set at ΔE Δab > 2 .t-test .Data analysis was performed using SPSS 27 for Windows . Descriptive analysis included mean, median and standard deviation. The Kolmogorov–Smirnov Test showed a non-normal distribution, and an E log transformation was made. Data were analyzed using two-way ANOVA, and mean ΔE values were compared with a t-test was used according to a sample size calculation that considers test significance = 0.05, power = 0.9 and effect size = 1.6.To test for the difference in mean between the 2 groups, the . As performed in SPSS software, version 21, 9 samples in each group should be sufficient for achieving significant results at 0.05.The means and standard deviations of the color parameters L*, a* and b* of test groups are presented in p < 0.01)  for a 3.5-mm abutment height and (−2.02 ± 0.54) for a 5.5-mm abutment height. The B2/3 color group had the highest b* variable values, (1.03 ± 0.59) for a 3.5-mm abutment height and (1.72 ± 1.12) for a 5.5 abutment height. ∆E* values were calculated using the CIE76 and CIEDE2000 formula. Two-way ANOVA for the independent variables, abutment height and its interaction with crown color significantly influenced the ΔE values in the study groups ( < 0.01) .Means and standard deviations of the CIE76 and CIEDE2000 color difference of all groups are presented in The results of the present study suggest that the abutment height significantly affects the Δa*, Δb*, ΔL* and ΔE* variables of different zirconia crown shades. Thus, the null hypothesis was rejected.There are two main methods for color evaluation: visual and instrumental and commercially manufactured shade guides are used for the visual method, which is extremely difficult, due to multiple factors, such as environmental and lightening conditions, as well as viewer interpretation. In an objective color analysis with the spectrophotometer used in this study, according to other previous studies, more reliable and accurate results were found than subjective methods ,19. Prevab = 2.53) found in the A1/0 color group and a value of (ΔEab = 2.23) in the A2/3 color group when using a 5.5-mm abutment height. These findings, which were approved by different previous studies, are considered clinically unacceptable.In our study, ΔE* values using the CIE76 formula ranged from 0.96 to 2.53, with the highest value  when using a translucent-shade cement before and after the cementation procedure, which may be considered clinically unacceptable. Moreover, an opaque cement results in a clinically unaccepted color change in 0.5 mm and in 2 mm zirconia disk thicknesses. Hence, to prevent bias, ti-base abutments were not cemented in this study [One previous study reported the effect of abutment color on the restoration color and suggested increasing the thickness of the restoration when using a titanium abutment . This sois study . One othis study . L* valuTo achieve higher translucency, attempts were made by producing partially stabilized 4Y- and 5Y-TZP materials with a high nonbirefringent cubic phase content. Nowadays, we know that the translucency of zirconia materials increases with higher Y-TZP contents (5Y-TZP > 4Y-TZP > 3-YTZP). Zirconia with a microstructure with a grain size of under 100 nm is expected to allow for light transmission without scattering. Therefore, speed and super-speed sintering methods resulting in ultrafine and dense Y-TZP grains by growth prevention are used to achieve high translucency . TherefoFor more healthy soft tissues in the aesthetic zone, the crown’s ti-base interface is usually located 1 mm sub-gingivally, and different gingival ti-base heights can be used depending on the depth of the implant.Silva et al.  reportedThe limitations of this in vitro study include the in vitro color assessment, the fact that only one thickness of restoration was tested, and the single translucent zirconia brand. These factors may lead to different spectrophotometric results. Another limitation of this is study is the that cement effect was not tested when each specimen acted as its own control group. The results of this study may, however, help setting guidelines for anterior zirconia implant reconstructions.ab > 2) in A1/0 and A2/3 shades of monolithic translucent zirconia.Using a 5.5 mm-height ti-base abutment may produce a clinically unacceptable outcome (ΔEWhen restoring A1/0 and A2/3 shades of monolithic anterior zirconia restorations using high ti-base abutments, the final color may be largely affected.If possible, using a short ti-base abutment may be favorable when restoring a monolithic anterior A1/0 and A2/3 shade zirconia, providing that the retention forces must be considered, depending on the length of the restored crown.From this study, the following conclusions were drawn: