Neurotrophin signaling via receptor tyrosine kinases is essential for the development and function of the nervous system in vertebrates. TrkB activation and signaling show substantial differences to other receptor tyrosine kinases of the Trk family that mediate the responses to nerve growth factor and neurotrophin-3. Growing evidence suggests that TrkB cell surface expression is highly regulated and determines the sensitivity of neurons to brain-derived neurotrophic factor (BDNF). This translocation of TrkB depends on co-factors and modulators of cAMP levels, N-glycosylation, and receptor transactivation. This process can occur in very short time periods and the resulting rapid modulation of target cell sensitivity to BDNF could represent a mechanism for fine-tuning of synaptic plasticity and communication in complex neuronal networks. This review focuses on those modulatory mechanisms in neurons that regulate responsiveness to BDNF via control of TrkB surface expression. Nerve growth factor (NGF) was the first member of the neurotrophin family that was discovered as a survival factor for distinct populations of neurons during a critical period of development. When brain-derived neurotrophic factor (BDNF) and the other members of the neurotrophin family were identified, it became apparent that the responsiveness of BDNF-sensitive neurons was also qualitatively different from NGF-dependent neurons. These differences can be explained by differential target cell responsiveness to BDNF rather than differential expression of the corresponding TrkB receptor. In the present article, we aim to provide an overview about some historic aspects that first pointed to differences between NGF and BDNF, and recent findings on molecular mechanisms how target cell sensitivity to BDNF signaling is regulated by TrkB cell surface expression. These mechanisms could explain differential responsiveness of developing neurons to NGF and BDNF.Work by Viktor Hamburger and others has shown that many types of neurons are generated in excess in the embryonic nervous system of vertebrates and that only subpopulations that are supported by neurotrophic factors are maintained (reviewed by Purves and Lichtman 2A-R) depend on the presence of TrkB  and spinal motoneurons . First, neuronal activity triggers Ca2+ entry via AMPA and NMDA receptors (a). Ca2+ stimulates adenylyl cyclase activity, thus causing an elevation of cAMP levels which trigger PKA and PI3K activity (b). This leads to the mobilization of a rapidly available intracellular reserve pool of TrkB (c). TrkB containing vesicles are transported in a microtubule-dependent manner to distinct sites at the cell surface where they integrate, such as dendritic spines. In the dendritic target area, TrkB is transported in an actin-dependent manner via Myosin Va and associates with PSD-95 for guided integration into the PSD (d). TrkB is then able to bind BDNF and gets activated via autophosphorylation at C-terminal tyrosine residues (e).In summary, these studies provide evidence that cAMP-mediated TrkB surface translocation in dendritic spines but also axon terminals involves several critical steps Fig. . First, Elevated levels of cAMP play a central role in the translocation of TrkB to distinct cell surface regions within neurons. Thus, it is not surprising that G protein–coupled receptors (GPCRs) were proposed as key activators and potential central physiological regulators for the effects observed in cultured neurons after cAMP treatment , phospholipase C (PLC), or L- and N-type Ca2+ channels  via stimulation of phospholipase C-beta (PLC-β) activity    constitute the largest and most diverse family of transmembrane receptors , or mannose (Man) modifies the core oligosaccharide (Moremen et al. Glycan structures on newly synthesized glycoproteins are crucial for protein secretion. N-glycosylation is the most frequent form of posttranslational modification in the ER (Moremen et al. An unconventional secretory pathway from the ER to the cell surface that is independent of the Golgi apparatus has recently been described (Hanus et al. Taken together, N-glycosylation appears as a modulatory mechanism for retention or export of Trk receptors from the ER. While TrkA and insulin receptors require N-glycosylation for surface export, the same condition retains TrkB in the ER, leading to the conclusion that N-glycosylation has individual effects on distinct Trk receptors. Notably, TrkB export from the ER after EGF-mediated transactivation is a very fast process and occurs within seconds. For this reason, it appears unlikely that this mechanism involves processing in the ERGIC and Golgi. This observation rather favors the idea of a direct ER export to the cell surface (Puehringer et al. The development and function of neuronal networks, especially correct communication and adequate responses to incoming synaptic signals, crucially depend on neurotrophin signaling. TrkB and TrkA differ in the way how they induce cell death in the absence of corresponding ligands (Nikoletopoulou et al. The regulation of TrkB cell surface expression has many advantages for the function of BDNF/TrkB signaling in the context of synaptic plasticity. Changes in subcellular cAMP could act in a highly local manner and thus fine-tune individual synapses (Maiellaro et al. So far, it remains elusive whether the simultaneous activity of different afferents is required to induce BDNF-/TrkB-mediated LTP in such circuits. LTP then would be induced in a spatio-temporal manner only when both afferents are active. On the other side, such a scenario also would require a highly precise mechanism for removal of TrkB from the cell surface, and it is not clear whether this occurs only after ligand-induced endocytosis or also by other mechanisms. Alterations of such control mechanisms could cause aberrant synaptic plasticity and network communication and thus might be involved in numerous neuropsychiatric diseases.


Fusarium oxysporum f. sp. cubense (Foc) symptoms. A total of 117,814 bacterial and 17,317 fungal operational taxonomy units (OTUs) were identified in the rhizosphere, roots, and corm of the host plant. Results revealed that bacterial and fungal microbiota present in roots and corm primarily emanated from the rhizosphere. The composition of bacterial communities in the rhizosphere, roots, and corm were different, with more diversity observed in the rhizosphere and less in the corm. However, distinct sample types i.e., without (asymptomatic) and with (symptomatic) Fusarium symptoms were the major drivers of the fungal community composition. Considering the high relative abundance among samples, we identified core microbiomes with bacterial and fungal OTUs classified into 20 families and colonizing distinct plant components of banana. Our core microbiome assigned 129 bacterial and 37 fungal genera to known taxa.We assessed the diversity, structure, and assemblage of bacterial and fungal communities associated with banana plants with and without  Rhizospheric and endophytic microbiota have been shown to significantly improve plant health and development ,2. BenefMusaceae spp.) are cultivated throughout the humid tropics and sub-tropics. In sub-Saharan Africa (SSA), bananas are an important component of the diet and a crucial source of income for many small holder farmers. Disease pressure is the major threat threatening banana productivity in the region [Fusarium oxysporum f. sp. cubense (Foc), lack of pesticides, and appropriate resistant varieties encouraged the search for alternatives to sustain productivity. Foc race 1 is present everywhere in SSA hampering dessert banana (of the Musa subgroup AAB) productivity [Bananas  race 1. Symptomatic banana plants were selected based on the morphological symptoms including yellow coloration of leaves and maroon color lines inside the pseudostem. In addition, we demonstrated the composition and assemblage of the naturally occurring microbiome in the rhizosphere, root, and corm samples. Our study is the first to describe an inventory of bacterial and fungal communities associated with the components of asymptomatic and symptomatic banana plants infected by Foc. In addition, we describe core microbiomes in the rhizosphere, root, and corm and established a model for studying banana microbiota.To elucidate the role of the microbiome in plant growth and disease control, it is necessary to investigate the microbiome dynamics and distribution in different plant components. Thus, the present investigation was conducted to study the microbiome (both bacteria and fungi) structure and mode of associations with asymptomatic and symptomatic banana plants infected by Musa subgroup AAB) is a popular dessert banana cultivar in east Africa that is susceptible to Foc. The rhizosphere, roots, and corm of asymptomatic and symptomatic plants were targeted for sampling. Symptomatic banana plants exhibited yellowing leaves with brown streak discoloration inside the pseudostem and corm, and asymptomatic plants had green leaves with no discoloration inside the pseudostem and corm  of fungi was amplified . AmplifiThe library was loaded onto the Illumina platform at a concentration of 10–20 pM for cluster generation and sequencing. The template fragments were sequenced in both the forward and reverse direction through Paired-End sequencing on the Illumina platform.DNA (chimeras) sequences were filtered using usearch61 algorithm (de novo mode) and generated in silico using the FLASH tool with a minimum 10 bp overlap to recreate the V3–V4 region. All the samples were pooled in a single file, processed, and clustered to facilitate resemblance among different plant components and locations. The taxonomic names were assigned with UCLUST algorithm. OTUs for bacterial and fungal communities correlated with their abundances, were organized into a BIOM file. QIIME was used for downstream processing and intra-sample analysis or Alpha (α) and Beta (β) diversity calculations to analyze species richness. We used non-metric multidimensional scaling (NMDS) and principal coordinate analysis (PCoA) plots to visualize differences in bacterial and fungal communities composition among samples.Differences in microbial community richness among rhizosphere, root, and corm of banana were evaluated with chaos1 estimator and the Shannon diversity index. The Bray–Curtis dissimilarity matrix was calculated for bacterial and fungal communities and used for PCoA analysis with QIIME.We investigated core and non-core microbial communities (both for bacteria and fungi) in combination of sample type and location with MySQL query over the filtered OTU table. Further, we evaluated the relative abundance of each OTU in different samples and taxonomical histograms were plotted.The sequence data were deposited in NCBI with SRA accession PRJNA493905 and PRJNA494050.We characterized the bacterial and fungal communities associated with each plant component , location, and sample types (asymptomatic and symptomatic). A total of 16 million reads, with an average of 0.9 and 0.5 million reads per sample type, were generated for 16S and ITS2, respectively. A total of 4.6 million reads from 16S and 2.5 million reads from ITS2 were clustered at ≥97% sequence identity after the removal of low-quality reads via the UCLUST algorithm. A total of 117,814 bacterial and 17,317 fungal operational taxonomy units (OTU) were recovered.We analyzed the variables such as plant component, location, and sample types (asymptomatic and symptomatic). Among the rhizosphere, root, and corm, a specific association was observed for both bacterial and fungal communities among the sample types. The rhizosphere significantly impacted the bacterial communities regardless of plant components. However, the location had a significant effect on fungal communities . High vaRhizobiales, Xanthomonadales, and Burkholderiales were the most dominant bacterial orders associated with each plant component in both locations for asymptomatic and symptomatic sample types. Among the fungi, Hypocreales was the most dominant order followed by Agaricales, Incertae_sedis, Sordariales, Mortierellales, and Eurotiales in both locations for asymptomatic and symptomatic sample types  in Kilimanjaro and Chthoniobacteraceae (18.36%) and Sphingomonadaceae (13.34%) in Arusha; both were highly abundant in sample types. In case of fungal communities, Nectriaceae were found to be preferential colonizers and represented 23% of the relative abundance for both locations, followed by Plectosphaerellaceae (17.14%), Mortierellaceae (9.54%), and Trichocomaceae (8.42%) of sample types.Members of Hyphomicrobiaceae were more abundant in the rhizosphere, and Pseudomonadaceae in the roots and corm in both locations of sample types. For fungal communities, Mortierellaceae was observed with the highest relative abundance in the rhizosphere, Nectriaceae in roots, and Plectosphaerellaceae in corm of both locations of sample types. Notably, a small group of bacterial and fungal communities were not specifically accommodated by any particular plant component. This includes core bacterial communities associated with Chthoniobacteraceae and Sphingomonadaceae, and core fungal communities were associated with Trichocomaceae and Auriculariaceae.Bacterial communities classified as members of Bacillus, Pseudomonas, and Trichoderma  that is associated with promoting plant growth. The rhizosphere and root samples also included fungi belonging to Aspergillus and Trichoderma, which are known for their biocontrol attributes. Bacterial communities such as Pseudomonadaceae, which were supposed to be in high relative abundance in rhizosphere, root, and corm, have been poorly explored with respect to their plant growth promoting attributes in bananas. Other groups such as Hyphomicrobiaceae and Sphingomonadaceae have never been explored for their plant growth promoting traits. Regarding fungal communities, Trichoderma was among the highly abundant groups identified in the rhizosphere, root, and corm whose plant growth traits are known. More than 92.8% of bacterial groups that were identified have never been explored. In the case of fungal communities, very few genera (<1%) have been explored from any host plant  samples were with a lower bacterial and fungal diversity than the asymptomatic samples. This may be due to the disease stress, which is directly linked to the decreased value of available carbon for microbes in the rhizosphere, responsible for specific microbial groups selection, and thus regulating their community compositions. Banana plant resistance and Fusarium aggressiveness in different plant components also contribute to bacterial and fungal prevalence. In both locations, bacterial and fungal OTU counts were maximum in the rhizosphere followed by root and corm in sample types (We demonstrated that the rhizosphere had the greatest diversity of bacterial and fungal communities in the banana plant  but thatle types . Host plle types . Our resle types . NotablyBacillus, Pseudomonas, and some free-living diazotrophs such as Azospirillum and Bradyrhizobium which contribute to efficient nutrient acquisition, promote plant growth, and control soil-borne diseases. Pseudomonas and Bacillus, commonly found in the banana rhizosphere are known to promote growth, reduce stress, and act as biocontrol agents against diverse Fusarium-infected plant diseases [Aspergillus which has already been reported for its contribution to plant growth and induced resistance against phytopathogens. Beneficial interactions of fungal communities with host plant roots are also known to improve nutrient acquisition [A fraction of the core bacterial and fungal communities identified in the present study have previously been reported, but a larger proportion have not been reported. Some core bacterial and fungal communities were known to stimulate plant growth and promote health in various crops. We infer that these beneficial microbial communities are positively correlated with banana health. These include diseases . Host pldiseases ,24,25. Wuisition ,28,29,30Our study revealed that banana plants harbor rich and diverse bacterial and fungal communities, which decreases from the rhizosphere to the roots and corm. Rhizosphere, roots, and corm components impacted bacterial communities, and different sample types influenced fungal communities distribution. Besides the high taxonomic and functional diversity in bacterial communities, we observed about 92.8% of the total relative abundance. By comparing communities in other crops, we state that several of the communities discovered in banana could serve as key nodes for plant growth and health.


Blended web-based and face-to-face (F2F) treatment is a promising electronic health service because the strengths of one mode of delivery should compensate for the weaknesses of the other.The aim of this study was to explore this compensation by examining patients’ user experience (UX) in a blended smoking cessation treatment (BSCT) in routine care.Data on patients’ UX were collected through in-depth interviews (n=10) at an outpatient smoking cessation clinic in the Netherlands. A content analysis of the semantic domains was used to analyze patients’ UX. To describe the UX, the Hassenzahl UX model was applied, examining 4 of the 5 key elements of UX from a user’s perspective: (1) patients’ standards and expectations, (2) apparent character (pragmatic and hedonic attributes), (3) usage situation, and (4) consequences .BSCT appeared to be a mostly positively experienced service. Patients had a positive-pragmatic standard and neutral-open expectation toward BSCT at the treatment start. The pragmatic attributes of the F2F sessions were mostly perceived as positive, whereas the pragmatic attributes of the web sessions were perceived as both positive and negative. For the hedonic attributes, there seemed to be a difference between the F2F and web sessions. Specifically, the hedonic attributes of the web sessions were experienced as mostly negative, whereas those of the F2F sessions were experienced as mostly positive. For the usage situation, the physical and social contexts were experienced positively, whereas the task and technical contexts were experienced negatively. Nevertheless, the consequential appeal of BSCT was positive. However, the consequential emotions and behavior varied, ultimately resulting in diverse combinations of consequential appeal, emotions, and behavior .This study provided insights into the UX of a blended treatment, and the results support the expectation that in a blended treatment, the strengths of one mode of delivery may compensate for the weaknesses of the other. However, in this certain setting, this is mainly achieved in only one way: F2F sessions compensated for the weaknesses of the web sessions. As a practical conclusion, this may mean that the web sessions, supported by the strengths of the F2F sessions, offer an interesting approach for further improving the blended treatment. Our theoretical findings reflect the relevance of the aspects of hedonism, such as fun, joy, or happiness in the UX, which were not mentioned in relation to the web sessions and were only scarcely mentioned in relation to the F2F sessions. Future research should further investigate the role of hedonistic aspects in a blended treatment and whether increased enjoyment of a blended treatment could increase treatment adherence and, ultimately, effectiveness. Health care is undergoing a sea change driven by the progress in digital technology . One of One of the main elements clarifying the individual’s use of services in general  and eHeavia a user interface and F2F communication in counselling sessions.Usually, the term UX refers to products, services, and objects that a person interacts with through a user interface . HoweverAlthough a number of studies have examined the blended treatment , little features of a product or service, a process is triggered, in which the user constructs the UX  are selected and combined by the treatment developers independently of the patients that ultimately follow the treatment. Since the features are not constructed by the users, the product features only play a minor role in this study. In turn, the focus is placed on the patients’ response to the treatment’s features to explore the UX from the user’s perspective in a narrower sense. This means that the UX from a user’s perspective is built based on only four of these five key elements: (1) the patient’s standards and expectations, (2) the apparent character, (3) the usage situation, and (4) the consequences. In the following paragraphs, each key element is described and illustrated by examples of how it applies to the blended treatment in this study.features of a product or service refer to its content, presentation, functionality, and interaction [via a Web-based smoking diary). More details about the study intervention are provided below in the Methods section.The eraction ,24. The eraction  that comstandards and expectations are based on their experiences with the other services [The patients’ services ,24 with pragmatic and hedonic attributes [utility  and usability  of a service, such as BSCT. Hedonic attributes of BSCT refer to stimulation , identification , and evocation .When confronted with a service, an apparent character is constructed by the user. The apparent character is a cognitive structure representing tributes ,24. Pragtechnical, task-related, physical, and social contexts. These situations are different between patients and over the course of the treatment, especially for the Web-based sessions. For example, filling in a smoking diary while being on your own in a silent surrounding may result in different consequences than doing this in the living room with a partner and children around you.The usage situation moderates the consequences of the apparent character ,24 and rappeal, emotions, and behavior [The fit of the apparent character and the usage situation leads to three consequences: behavior ,24. For As UX has been shown as an important factor in explaining the behavior of a user in general , and patBSCT is a clinician-led intervention  which coThe current study is a substudy of the LiveSmokefree study—a single-center randomized controlled noninferiority trial with parallel group design, which examines the effectiveness of BSCT as compared with F2F treatment. The inclusion criteria for the LiveSmokefree study were (1) aged 18 years or older, (2) willing to quit smoking, (3) current daily smoker (at least one cigarette a day), and (4) speaking/reading/writing Dutch.A purposive sample (n=10) of the participants from the blended arm of the LiveSmokefree study  that hadBoth the LiveSmokefree study and this substudy on patients’ UX were approved by the accredited Medical Research Ethics Committee Twente (P14-37/NL50944.044.14). The LiveSmokefree study was registered in the Dutch Trial Registration (NTR5113).Qualitative data about the patients’ UX was collected by in-depth semi-structured interviews. The interview guide  was deveThe interviews were conducted by the first author (LS) between October 2016 and March 2017. Because LS is not a Dutch native speaker, he was supported by trained Dutch research assistants to avoid possible ambiguities and linguistic misunderstandings. On the date of the interview, the interviewees were picked up from the waiting area of the SRP and led to a neutral meeting room. After receiving permission for audio recording, the interviewer read a written introduction, which emphasized that the patient was invited to recall and describe (“tell stories”) their UX. After this briefing, a general stimulus  was used to start. Interviews followed a detailed written interview guide , but werThe audio-recordings were transcribed verbatim by trained research assistants following the guidelines for data preparation and transcription, as described by McLellan et al , and werThe data regarding the patients’ age, sex, education level, internet skills, nicotine dependence, and counselor  were acqThe data about adherence and smoking status  were acqBased on the semi-structured interview guide, content analysis was used to analyze all the interviews. The codebook was developed by two research team members , building on the interview guide and the research goals related to the clinical setting  ). The coAfter coding, all coded Dutch quotes were paraphrased in English by LS and collected in a table . ApplyinIn the following, the patient characteristics are presented first. Then, the positive and negative statements for each key element are described. As far as possible, this is done first for BSCT in general and then for the F2F and Web sessions. It is to be noted that the analysis and presentation methods were clarified after the interview phase, and the statements were not always available in every area.Patients’ characteristics are shown in In general, the patients approached BSCT mostly with a positive-pragmatic standard and a neutral-open expectation. None of the patients had followed a blended treatment or a Web-based treatment before. Therefore, their standards and expectations were based mainly on earlier experiences with F2F sessions, with earlier stop smoking attempts, and with ICT use in general. Only one patient (#34) used health-apps . However, most of the patients (7/10) had received F2F counseling before, participated in a group therapy (#34), or were familiar with mindfulness .F2F sessions, positive standards predominated. Patients said, for example, that “Human touch is important” (#75), quitting is easier with F2F support , F2F treatment is “ideal,” and it “adapts to your competencies” (#12). One patient, however, considered that it “can be hard if you dislike the counselor” (#14).For earlier stop smoking attempts, patients had the standard that the quitting success may depend on themselves , on missing support .Building amongst others on ICT-use in general, while being familiar with using ICT , the majority of patients showed a pragmatic standard “Computer is a tool” ; “I am not a computer freak” (#12); “Computer is not my way” (#10); or “I am neither a forerunner nor a left behind” (#25). Only one patient (#34) reported that he “personalizes his mobile.” Most patients also emphasized that they do not prefer computer-mediated communication over F2F communication because it “leads to misunderstandings” (#53), “it is easier to cheat online” , “it is easier to do sloppy” (34), “online information is not as important as written on paper” (#25), or “I do not trust internet information” (#509). Three of the patients  reported that they use mobile devices  more often, for example, “I use the laptop less since I have a tablet” (#25) or “I prefer mobile over PC” (#27).For BSCT in general, most patients  described their expectations as “neutral” or “not clear,” while some  emphasized to expect support from BSCT, saying, for example, that they want the counselor to be “a driving force” (#10) or that they expect “to get more grip on smoking cessation” (#34). One patient (#14) remarked that BSCT “is new and sounds interesting.”Referring to pragmatic attributes (usability and utility) were experienced mostly positive while the hedonic attributes , especially for the Web sessions, tended to be negative.While being confronted with BSCT and moderated by their standards and expectations, the apparent character of BSCT that the patients constructed, seemed to be both positive and negative. The usability and utility) were experienced as good. However, some patients also criticized pragmatic aspects of BSCT, especially of the Web sessions, which indicated possibilities for further improvements.BSCT’s pragmatic attributes , “there have been no problems” (#509), “everyone was kind” (#34) “everything was clear and easy to use” (#53), “all was quite logical” (#14), the “treatment was picked up well” , “BSCT parts connected to each other” , and that “the intervals between sessions were fine” (#53). One patient (#14) reported “less travelling”  as an advantage of BSCT, while another patient (#10) found that “still having to travel to the hospital at all” is a disadvantage. Further negative aspects of usability reported were the “long waiting list” before treatment start  (Note: regular waiting time before treatment start was around two months), “the long waiting times” in the waiting area before start of a F2F session (#14), that it was “not clear where to turn to outside the office hours” (#14), that “intervals between sessions were too long” , and that “not everything was explained in detail” (#25) and that the patient was “surprised about the order of the sessions” (#25).Most patients experienced the usability of the F2F sessions was experienced as “easy” (#25) or as “easier than web” (#27). Yet some patients criticized “that the counselor did not have enough time”  or that the sessions were “slow and time consuming” .The usability ofWeb sessions as “easy to use,” while three patients  reported the opposite (“not easy to use”). The patients criticized that the Web sessions were “too time demanding” , there was “a lot of repetition” , they “did not get immediate response” (#14), they “did not receive online assignments” (#27), and the “login would have been easier if you do not have to remember your password” (#27). Furthermore, two patients  reported that they did the smoking registration on paper before doing it on the Web because “it was simpler” (#106). However, this was “double work” (#106). Yet the patients liked “to be notified about new Web content automatically” (#75), that “emails and phone calls raised awareness” (#34), that “filling in forms online was handy” (#34), and “online saved time” (#25).Six patients , experienced the utility of BSCT in general, the patients experienced the utility as positive, finding that “all BSCT parts were helpful—some more, some less” (#53), BSCT “matched my quitting process” (#53), “all has been discussed” (#106), “there was progress” (#106), BSCT “offered support” (#27), or “Web only would not have offered what I needed” (#75).With regard to the utility of the F2F session was experienced as positive by most patients (7/10) also. Patients reported that F2F “offered flexibility” (#75) as “I could talk to the counselors about all of my problems” (#509), “all has been discussed” (#14), that with F2F “it was easier to ask questions” (#14), F2F “you got direct answers” (#14), F2F “stimulated more than web” (#10), and F2F “with medication was better than medication only” (#106). The counselors “reinforced” , “stimulated” , “offered support” , “shared good metaphors” (#53), and “explained everything very well” (14). Three patients experienced the F2F session as not useful, saying that the counselors “did not offer enough support” , “did not reinforce” (#12), “did not motivate” (#12), “did not discuss all alternatives” (#34), and “asked too much questions” (#27).The utility of the Web sessions, there were both positive and negative experiences. Some patients had a predominantly negative experience saying that “reporting via Web was too time demanding” (#509), that Web “offered too much information” (#106), that Web “did not match my quitting process” , that “a computer does not answer” (#14) and that Web “does not work for me” (#75). Furthermore, ideas for improvement were reported, such as “an App would be better than web” (#34) and other services should be included, such as “short reinforcements via WhatsApp, emails, in-between sessions, video instructions, helpdesk, chat support, short instructions” (#34) and “audio information” (text to speech) (#27). However, patients also reported positive experiences saying that the Web “offered support in difficult moments” (#53), Web “offered tips” (#53), and “it was good to have information available online” .For the stimulation, identification, and evocation), BSCT was experienced both positively and negatively. While some patients felt stimulated by BSCT, others reported being demotivated. Especially for the Web sessions, most patients reported low identification. Also, the Web sessions evoked mostly negative comparisons and induced several ideas for improvements.For the hedonic attributes , to “discuss costs of smoking” (#12), to “think” , to “dig deeper” (#509), or to “look back” (#75). Patients also reported that the carbon monoxide measurements during the F2F sessions stimulated quitting . On the other hand, patients reported that “BSCT did not offer new things” (#34) or was “not interesting” (#14), and that certain interventions  were “not new” (#25). Furthermore, patients were demotivated by “always the same questions” (#27), by “digging too deep” (#27), and by contradictory goals (quitting smoking vs weight reduction) (#27).For F2F sessions, patients said that the “counselor had no impact” . However, some patients  reported that they were reinforced by the counselors to use the Web sessions.For the Web sessions, one patient said, that Web “broadened your awareness” (#75), whereas the majority of patients reported no or low stimulation saying that “online won’t get through to me” , “online exchange with the counselor did not affect extraordinary” , and to be demotivated by the Web sessions  or computer use (#106).For the BSCT in general patients could identify linking to individual features, such as “perseverance” or “self-control.” However, for the Web sessions, most patients reported low identification. The ones showing higher identification with the Web sessions did this by referring to personal contact with the counselor. Patients found it easier with the F2F sessions than the Web sessions of BSCT.For BSCT in general, patients reported that BSCT linked to individual features, such as “perseverance” (#75), “self-control” (#75), “the ability to work based on reading and writing” (#75), “IT-skills” (#10), and “age” (#10). However, one patient (#27) reported that she “felt treated like a child” and that she “lost her rhythms.”Related to F2F sessions patients reported that these “felt more familiar” (#106), that patients liked “the F2F sessions the most” (#53) and “talking to the ladies” (#10)  refers to the female counselors).For the Web sessions, most patients reported low identification, saying, “I don't feel like it much” (#106) or “not to like online” , that “online is not my style” , to “prefer on paper” (#25), or being “too stupid for IT” (#10). One patient (#75) showed a higher identification with the Web sessions, emphasizing “Web I did for myself,” “I know why I did Web,” and “I understood the process.” In turn, she criticized saying that “online did not give the opportunity to make it more personal” (#75). Three patients reported that the Web parts supported their personal contact with the counselor, mentioning that via Web parts “I had contact with her” and “they knew something about me” (#509), that “during the F2F sessions it became clear that the counselor reads the Web content“ (#25), that “I had the idea that it is used on the other side” (#53), and that “you knew there is someone behind it” (#34). In turn, three patients reported that “you didn’t know who has written the content” (#15), that “computer did not talk to you” , and that “you did not get the feeling that there is a human being on the other side” (#12).For the Web sessions, the patients reported several negative comparisons, such as “Web was like handling a machine, because you are not sitting opposite to each other” (#106), Web sessions were like “bookkeeping” , like “a manual” (#53), like “filling in tax forms” (#10), and like “paper” (#27).For the technical context had a negative impact on the UX. Especially the Web sessions depended on the technical factors, which were criticized. Furthermore, referring to the task context of BSCT in general, some patients reported not having enough time for the treatment. Both the physical and the social context were described as mostly positive.For the usage situation, mostly the Web sessions, criticizing by saying that Web “did not work on iPad” . Although the patients had been informed at start of the treatment that the software for the Web session could not be used on tablet computers, they would have preferred to use tablets because the “Tablet is always on, Laptop not”  and tablet “is more comfortable” (#10), or because they  moved from laptop to tablet during BSCT. Furthermore, for the use of computers for the Web sessions, the patients criticized by saying that they “had to start up the laptop, which takes time” .For the technical situation, the patients referred to the Referring to tasks, patients reported not to have enough time for the BSCT “because of other tasks” (#509) or “because of family tasks” (#106), or to feel “sometimes stressed—sometimes relaxed” (#27).F2F sessions, the patients reported little about the physical usage situation, mentioning only “that I live close to the hospital” (#25) and “that the treatment took place in the old building, which was not a nice place”  (Note: Between the patients treatment and the interviews the department moved to a new building).For the Web sessions, the patients shared more information about the physical usage situation reporting that they did the Web sessions at “my own home office” , in a “hobby room upstairs, which is a nice place” (#10), “upstairs, where it is quite hot in the summer” (#14), “with the laptop at the dining table with wife and children around me” (#53), “in the kitchen” (#106), and “with laptop lying on the bed in the sleeping room” (#509).For the BSCT in general, most patients reported feeling supported by the family, saying that everyone “supported”  and “complimented” (#53), that “family motivated stopping” (#106) and “nearly no one in our family smokes” (#14), that “my partner stimulated” , “offered incentives” , “accompanied” (#14), “gave feedback on better health conditions” (#53) and “does not smoke” (#509), and that “children supported” (#27), “children were positive about quitting” (#53) and “my son also quit” (#14). One patient said he (#25”) “lives alone” and “did not tell much about BSCT”; she reported that “everyone was sceptic of the quitting success.” One patient (#27) reported that “her partner did not support,” “questioned the Web sessions,” and broke “the agreement to smoke outside only.”For the social situation during For friends and colleagues, the patients reported that “none of my friends smoke” (#10), “no one smokes inside” (#14), and that “colleagues also have positive experiences with cessation treatment” (#53). Furthermore, one patient emphasized that he “stimulates others to quit smoking” (#10).BSCT in general had a positive appeal, while emotions  varied. Again, there was clear distinction between the F2F sessions and the Web sessions. Similar to the emotional consequences, the behavioral consequences  also varied, ultimately resulting in diverse combinations of consequential appeal, emotions, and behavior.Overall, BSCT in general, appealed to be “good.” The patients reported that BSCT was a “mix of talking and reading” (#14) and it “offered variety” (#75). The “shared information both F2F and Web was fine” (#106) and “Web only would not have been so easy” (#53). F2F sessions and Web sessions were “quite different” (#34); “sometime F2F was better—sometimes Web was better” (#14) and “Web was an extension of F2F” (#53). One patient (#27) emphasized the medical treatment saying “Champix was good.”For six patients , F2F sessions mostly appealed to be “good.” The patients reported that the F2F sessions were “fine” (#509) or “finer than web” (#106) and that the F2F sessions were “most important” (#53) or “most important at treatment start” (#34). One patient (#12) emphasized “that only F2F touches your heart” and that he would go for F2F “100% in all facets.” However, one patient (#27) said that the F2F sessions were “whiny.” For the counselors, one patient (#27) described her counselor as “nice,” while another patient (#34) said that his counselor had a “stiff posture” and that she was “annoying,” “pedantic” and “cumbersome.”The Web sessions, the majority of patients reported a negative appeal, saying that the Web sessions “yielded nothing” , were “a lot” , “cumbersome” (#106), “boring” , “tiring” (#27), “nonsense” , and “dead” (#10). However, one patient (#75) said that “Web was nice” while others—also referring to positive appeal—reported that the Web sessions could be done “comfortable at home” (#34) and that Web was “a serious matter” (#25), although she would not go for “Web only.”For the BSCT in general, some not. Again, there was a distinction between F2F sessions and Web sessions, but not as clear as for the appeal.Emotional consequences varied—some patients were satisfied with BSCT in general, three patients reported to be satisfied  or “thankful” (#106). Furthermore, referring to negative emotions about BSCT in general, patients reported “feeling abandoned, left alone” (#12), “tension and the need to relax physically” (#75), and “contradictions between quitting smoking and weight reduction” (#27). One patient said that the F2F sessions and Web sessions stimulated “the same moods” (#25). The mood during the F2F sessions was “good” , while Web sessions were experienced as “unpleasant” (#27) and “making me nervous” (#34). One patient reported to feel “guilty because I did not stick to appointments” (#27).While two patients  said that they were not satisfied with adhered to BSCT in general, doing both the F2F sessions and the Web sessions. One of them (#14) said he “could have stopped after four sessions” because he was “sure not to need it in the future.” However, he continued BSCT “to do the counselors and researchers a favor.” Five patients  reported that they found the Web sessions “sloppy.” Furthermore, one patient (#27) mentioned that she “forgot about some of her sessions.”During the interviews, three patients  reported that they BSCT in general  was 6.5 (IQR 5.50-11.75). Based on a 60% threshold for both the F2F sessions and the Web sessions [Based on the auxiliary data , medium sessions , three pquitting. One (#106) mentioned that “I had no problems because I had medication (Champix)” and “I threw away my last shags.” The other one (#53) mentioned that he told himself “Never again!” and “Enough!” (Basta!), and that “he saved money for the holidays with his family.” Two patients  reported that they reduced smoking during BSCT.Based on the interviews and the auxiliary data, four patients  reported successful The variety of consequential appeals, emotions, and behavior could be summarized in three types of combinations: “positive,” “negative,” and “mixed” consequences.Three patients  experienced “positive” consequences. BSCT appealed to be good and they felt “satisfied”/“thankful,” adhered to the treatment and quit smoking.On the contrary, another three patients  experienced “negative” consequences: The Web sessions appealed negative  and BSCT in general resulted in negative emotions (abandoned/not satisfied). Ultimately, they did not adhere to the treatment and did not quit smoking.Mixed consequences: Three  of the four remaining patients did not quit smoking, while one (#10) did. Interestingly, BSCT in general appealed “good” to the nonquitters  while—for the quitter (#10) at least, the Web sessions appealed to be “nonsense.” Although two of the nonquitters  reported negative emotions (“tension”/“not satisfied”), these two patients at least partly adhered to BSCT . In turn, the third nonquitter (#27) reported positive emotions (“satisfied”) but did not adhere at all.To the remaining quitter (#10), although the Web sessions appealed to be “nonsense” and he did not adhere to BSCT in general, he reported positive emotions (“satisfied”) and ultimately quit smoking.This study aimed to provide insight in the UX of a blended treatment. In the light of this study, the expectation that the strength of one mode of delivery can compensate for the weaknesses of the other in blended treatment, can be partially supported because the F2F sessions compensated for the weaknesses of the Web sessions so that BSCT in general was mostly experienced positively.Our study described the UX of a BSCT using Hassenzahl’s key elements of UX from a user’s perspective ,24. OverAlthough patients’ pretreatment expectations toward BSCT were neutral and the Web sessions appealed negative, overall BSCT in general appeared to be positively experienced afterwards. This is in line with an evaluation study (n=7) by Kooistra et al  of a bleInterestingly, although the hedonistic gap made the Web sessions appeal negatively, the overall BSCT was experienced positively. This could support the assumption that in blended treatment the strength of one mode  may compensate for the weaknesses of the other  ,5. This We mainly found that the F2F sessions compensated for the weaknesses of the Web sessions. Yet three patients reported that the Web sessions influenced their personal contact with the counselor positively. Although the Web sessions mostly had a low identification and a negative appeal, the Web sessions supported the F2F sessions because these patients felt more related to the counselor. However, even though the Web sessions may have supported the F2F sessions, it should be noted that none of the patients indicated that the Web sessions compensated for the F2F sessions. It remains undecided if this is because there was no need for compensation as the F2F sessions were overall positive, or that the Web sessions were not able to compensate. It should also be taken into account that the routine care in the hospital was not Web based, the patients were of older age, and did not have an affinity for the internet , and the patients’ preferences for modes of delivery were not taken into account as they were not free to choose for BSCT because they were included in a randomized controlled trial. These factors may additionally explain the low positive impact of the Web sessions.The emotional and behavioral consequences varied, ultimately resulting in three types of combinations of appeal, emotions , and behavior : “positive,” “negative,” and “mixed.” These types can be used to work on UX profiles that can support further development of blended care and improve the matching between the treatment and patient .Further work needs to be done to investigate how the integration of F2F and Web treatments can be carried out to ultimately increase the effectiveness and efficiency of a blended treatment. This study provides a hint to explore this question by emphasizing the relevance of hedonic attributes in the UX. Even if the UX was predominantly positive because the hedonistic gap in the area of the Web sessions was compensated relatively easily by the F2F sessions, this does not mean that BSCT cannot be further improved to increase adherence and long-term abstinence. Hedonism could be a starting point for this. Further research on the following questions could be useful:Could the hedonistic gap in the Web sessions be not only due to the mode of delivery, but also the concrete content of the Web sessions? Perhaps, it was precisely the interventions that the patients experienced as nonhedonistic, which were the part of the Web sessions. This was neither explicitly considered in the treatment design nor asked for in detail in the interviews. However, this might have been the case because more standard exercises and messages could be offered on the Web more easily. A stronger involvement of patients in the early design stages of the Web sessions may help to prevent the hedonistic gap.May hedonism play a less prominent role in the health care context than in the other domains? Patients tend to approach a health problem with a pragmatic-neutral expectation, such as “What’s important is that it works. As long as it helps, I can also accept that it is unpleasant.” Consequently, hedonistic aspects, such as fun, enjoyment, pleasure, and aesthetics may not be expected in the first place, and therefore, may not be missed. Moreover, this may be compensated relatively easily by positive experiences with the counselors. However, if hedonism was less important in health care, it would contradict our conclusion that it should receive more attention.Could both scientific research and clinical practice use insights from persuasive systems design ,37, “nudHow do the apparent character and the consequential appeal and emotions relate to the quitting behavior? On the one hand, apparently a negative appeal  may lead to consequential combination of negative appeal, emotions, and behavior . On the other hand, it is also possible to distinguish between diverse episodic UXs ultimately leading to a cumulative UX , for exaThe data and model used in this study provided a rich insight into the UX of a blended treatment for smoking cessation in an ambulant clinical setting. Though this study yielded valuable knowledge for the understanding and improvement of BSCT and the matching of patients and treatment, limitations should be noted when interpreting the findings. First, the sample of patients used in this study was a purposive sample that was intended to represent the heterogeneity of the patients of an outpatient cessation clinic. Hence, it is uncertain, if the rather small sample (n=10) is representative of the population referring to characteristics, such as sex, age, internet skills, or educational level, and if the thematic saturation was reached with this sample size. It should also be considered that patients did not choose BSCT on their own but were randomly assigned to it because they participated in a randomized controlled trial. However, the high degree of consensus in the findings may indicate generalization of our main conclusions. Second, the interviews were conducted retrospectively. Conducting additional interviews at treatment start and during treatment could have offered a more valid insight in the process of patients’ UX construction . Third, the software that was used for the Web sessions was developed around 2005, which may have led to technical incommodities , which may have negatively impacted the UX. This assumption is based on the fact that patients often stated that they would have liked to do the Web sessions on their mobile device. We assume that a newer mobile device–compatible software with similarly good pragmatic attributes as the previous Flash-software could have also improved the hedonistic attributes and thus have led to more positive consequences. Fourth, the interviews were conducted with the first patients that followed the new blended version of the smoking cessation treatment. At that time, the treatment still had some teething problems, such as being new for the originally F2F counselors. We did not integrate the counselors’ views on the uptake of BSCT, and therefore, we cannot compensate for bias through inadequate treatment fidelity. Fifth, as long-term abstinence is the goal of a smoking cessation treatment, prolonged follow-up analysis of patients’ UX could reveal a different picture. For example, some patients may continue using the Web-based modality and benefit from this at a later stage, resulting in a UX that would be more in favor of the Web-based treatment. Conversely, relapse to smoking at a later stage may lead to a negative adjustment of the UX of the blended treatment. Sixth, we could not elaborate further on which specific parts of the Web sessions were experienced positively or negatively as we did not ask for these in detail in the interviews. Seventh, the study interventions are selected and combined by the researchers and treatment developers without considering the individual patients who ultimately followed the treatment. This resulted in a rather inflexible approach of blending  to allow for comparisons with the F2F treatment as usual in the randomized controlled trial (LiveSmokefree study) . This inThis study provides insight into the key elements of the UX of a blended treatment for smoking cessation and supports the expectation that in a blended treatment, one mode of delivery may compensate for the weaknesses of the other. However, in this certain setting, this could be mainly achieved in only one way: F2F sessions compensated for the weaknesses of the Web sessions. As a practical conclusion, this may mean that the Web sessions supported by the strength of the F2F sessions, offer an interesting approach for further improving the blended treatment in this specific context. Our theoretical findings reflect the relevance of the aspects of hedonism, such as fun, joy, or happiness in UX , which w


The use of graphene and its derivatives with excellent characteristics such as good electrical and mechanical properties and large specific surface area has gained the attention of researchers. Recently, novel nanocomposite materials based on graphene and conducting polymers including polyaniline (PANi), polypyrrole (PPy), poly  (PEDOT), polythiophene (PTh), and their derivatives have been widely used as active materials in gas sensing due to their unique electrical conductivity, redox property, and good operation at room temperature. Mixing these two materials exhibited better sensing performance compared to pure graphene and conductive polymers. This may be attributed to the large specific surface area of the nanocomposites, and also the synergistic effect between graphene and conducting polymers. A variety of graphene and conducting polymer nanocomposite preparation methods such as in situ polymerization, electropolymerization, solution mixing, self-assembly approach, etc. have been reported and utilization of these nanocomposites as sensing materials has been proven effective in improving the performance of gas sensors. Review of the recent research efforts and developments in the fabrication and application of graphene and conducting polymer nanocomposites for gas sensing is the aim of this review paper. These dications .Graphene is a p-type semiconductor that contains a larger hole to electron ratio concentration and has to pull an electron effect in a gas atmosphere . When grConducting polymers, including polypyrrole (PPy), polyaniline (PANi), polythiophene (PTh), and so on, have been used as the sensing materials of gas sensors. Conducting polymer-based gas sensors are more sensitive, with a shorter response time at room temperature, that tune both chemical and physical properties by using different substituents in comparison with most commercially available metal oxide (MO)-based gas sensors. Another advantage of conducting polymers is their synthesizing procedure is facilitated through chemical or electrochemical processes. Also, copolymerization or structural derivations can modify their polymer molecular chain structure .In recent years, the development of novel polymer nanocomposites has attracted significant worldwide research interest. The advantage of polymer-nanocomposite includes the value-added properties of the pure polymers without affecting their processability, inherent mechanical properties, and lightweight ,17,18. WNowadays, many studies investigated the performance of gas sensor-based graphene and its composites with metal oxides and polymers ,25,26,27A critical review of the published papers indicates that there is a gap in our knowledge about the comparison in preparation and sensing performance of graphene and different conducting polymers in the application of chemiresistive sensors for detecting various target gases. This article focuses on recent research efforts, developments, and approaches for the preparation of graphene and conducting polymer nanocomposites. The fabrication of chemiresistive gas sensors with graphene and conducting polymer nanocomposites is described along with a discussion of sensing performances.2, Fe2O3, ZnO, SnO2, and WO3. MOS materials possess good sensing properties, but require high operating temperatures [Sensors with accurate sensing performance have attracted much attention to monitoring and controlling emissions from various emitters . Gas seneratures . Theoreteratures . On the eratures . The seneratures ,43,45,46To enhance the sensitivity and selectivity of a resistive gas sensor, it is essential to understand the sensing mechanism. It is well known that the conductance of n-type semiconductors increases with a reducing analyte and decreases with an oxidizing one . The oppThe sensing performance parameters of the gas sensor include response, sensitivity, selectivity, stability, repeatability, response and recovery time, the limit of detection, and working temperature . The resFor reducing environments;o and Rg are the resistances of the sensor in background gas and the presence of target gas, respectively, and S is the response of the sensor. Based on the electrical response, different approaches are used to determine the sensitivity of a gas sensor. Sensitivity is the change degree in response to a certain concentration of target gas. The ability of a sensor to selectively respond is known as selectivity. Selectivity refers to the characteristics that determine whether a sensor can respond selectively to an analyte or a group of analytes. Repeatability is how much the gas sensor test results will be constant when they are tested in the same environment continuously and whether it can affect the working life of the sensor. Response time and recovery time are other important parameters for determining the performance of a sensor towards a specific gas. The response time and recovery time are defined as the time to reach 90% of the total change in resistance during exposure and removal of the target gas, respectively. The lowest concentration of target gas that can be detected by the gas sensor is known as the limit of detection (LOD). The temperature that can give the gas sensors its highest sensitivity is known as the working temperature [For oxidizing environments;perature ,53,54,55To detect the target gases, variety of materials such as conducting polymers ,57, carbNowadays, graphene and its derivatives have received attention owing to their unique properties such as good conductivity, large specific surface area, feasible adsorption of gas molecules, and their potential to be modified by functional groups as a sensing material for gas sensor fabrication ,65. On tSeveral studies reported that graphene and conducting polymer composites indicated excellent mechanical, thermal, gas barrier, electrical, and flame retardant properties in comparison with pure conducting polymers ,72,73,74Over the last few years research on incorporating graphene into polymer matrices to provide novel nanocomposite materials with enhanced electrical, thermal, mechanical, electrical, and other properties due to the large aspect and surface-to-volume ratios of the nanofiller has reseived extensive attention ,77,78,79The in situ polymerization involves chemical reactions. Normally in this technique, the nanofiller mixes with monomers in a solvent. The use of monomers can help to adjust the interactions between materials which makes possible intercalation and results in exfoliation and also compared to high molecular weight polymers, monomers diffuse into the galleries of the silicate more efficiently ,91. AlthThis section focuses on the synthesis of graphene and different conductive polymers  (PEDOT), etc.) nanocomposites and their application for gas sensing .The most widely used methods to synthesize graphene and PANi nanocomposites for the application of gas sensors are in situ chemical polymerization and solution mixing. In situ chemical polymerization was reported as an efficient method to uniformly disperse graphene oxide (GO) with a strong interaction between the GO and polymer matrix and . Typical2/rGO/PANi nanocomposite was synthesized by using the in situ polymerization technique [2 powder and NaOH were added in the same solution and then stirred to obtain the precipitate of SnO2/rGO/PANi composite [In situ chemical oxidative polymerization also was used for the preparation of graphene quantum dots (GQDs)/PANi ,107. SnOechnique ,109,110.The S, N: GQDs were prepared by the hydrothermal method in the presence of citric acid and thiourea. Ammonium persulfate (APS) was added to the mixture of aniline, 30 mL hydrochloric acid (HCl) and then transferred to the suspension of citric acid and thiourea. In the last step, the powder of S, N:GQDs/PANi hybrid was washed and dried in the oven. 2/GO/PANi by using the in-situ polymerization of aniline in the presence of TiO2/GO nanocomposite. Firstly, TiO2/GO composite was mixed with 50 mL of deionized water under stirring, and then aniline was added to the solution drop by drop in an ice water bath to obtain a hybrid material consisting of bulk reduced TiO2/GO/PANi [Junfeng Tian, et al. synthesized TiO/GO/PANi .4OH) solution firstly and then dissolved in N-methyl-2-pyrrolidone (NMP) while stirring. After that, graphene was added to the solution to make graphene-PANi nanocomposite [The most simple process method to prepare graphene and PANi nanocomposite is solution mixing ,112. Noromposite ,114.3 sensor based on rGO–PANi hybrid, which was synthesized using a simple, chemical oxidative polymerization method and coated on a flexible polyethylene terephthalate (PET) thin film was reported by Shouli Bai [3 exposure, good selectivity to some of the volatile organic compounds (VOCs) tested, and short response time and recovery time which were 20 s and 27 s, respectively at room temperature. GO-rambutan like PANi hollow nanosphere hybrid (GPA) for the detection of ammonia gas was prepared by the in situ chemical oxidation polymerization method and assembled on PET substrates as flexible devices [3, response and recovery time  and low detection limit of 50 ppb.The NHouli Bai . The com devices . The sen3 sensors based on /PANi loading on PTE and N-doped GQDs/PANi hybrid assembled on two different electrodes, silver (Ag) and aluminum (Al). The composite of S, N: GQDs and PANi lead to significant improvement in the response , and response and recovery time  at room temperature [3 gas sensor based on N-GQDs/PANi with Ag contact illustrated the best response of 110.92 compared to the sensor with an Al electrode (86.91) under 1500 ppm target gas at room temperature [Jaber Nasrollah Gavgani, et al.  and M. Hperature . The NH3perature .2/PANi composites were prepared by using the in situ chemical oxide polymerization for detecting different gases such as NH3 [4 [2S [2/PANi composite film exhibited 160% response to 20 ppm NH3, 9.1% toward 100 ppb H2S, and 26.1% to 100 ppm of CH4.The rGO@ SnOh as NH3 , CH4 [11s NH3 [4 , and H2S3 [4 [2S  at room 6H5–CH3) gas indicated the response of 11.6% and 90% toward 100 ppm and 5000 ppm C6H5–CH3 gas, respectively.The Gr/PANi nanocomposites were prepared by solution mixing  and in s3, CH4, C6H5–CH3, Benzene, and H2S. Among different NH3 gas sensors based on graphene and PANi nanocomposites, rGO–PANI hybrids loaded on a flexible PET thin film indicated the highest response of 344.2 to 100 ppm NH3 and the response time and recovery time were 20 s and 27 s, respectively [3. The enhancement of the sensing performance of the sensor based on rGO-PANi hybrid under NH3 exposure might be related to the acid-base deprotonation process of PANi nanoparticles, resulting in the selective response to NH3 gas.ectively . The sel3 gas sensor based on rGO/PANi hybrid sensing performance can be caused by the acid-base de-doping process of PANi nanoparticles and the synergetic effects between rGO and PANi [3.The enhancement of NHand PANi . This no3 gas sensor based on copper (II) tetrasulfophthalocyanine supported on a 3-dimensional nitrogen-doped graphene-based framework (CuTSPc@3D-(N)GF)/(PEDOT-PSS) nanocomposite  (PEDOT) nanocomposite. Yajie Yang, et al. ,118 prepomposite d.PEDOT:PSS is a widely used conjugated polymer due to its excellent electrical conductivity, high transparency, good processability, and low redox potential ,124. Fir2 gas compared to the sensor based on pure rGO [2 were also investigated. The PEDOT/RGO composite showed good sensing performance to NO2, higher operating temperature, and improved sensitivity. The gas sensor based on (CuTSPc@3D-(N)GF)/(PEDOT-PSS) nanocomposite indicated better response (5 and 53 times) and lower response and recovery times towards 200 ppm of NH3 compared with pure PEDOT-PSS and CuTSPc@3D-(N)GF [PEDOT, one of the most famous conducting polymers, attracted researchers’ attention due to its good conductivity, electrical properties associated with its low bandgap, and good stability ,127. Thepure rGO . The elepure rGO  and the 3D-(N)GF . 3 and NO2 gases. The gas-sensing performance of PEDOT/rGO nanocomposites prepared by in-situ polymerization technique revealed in contrast to other PEDOT/rGO nanocomposites, which were listed in 2 gas [As we can see in in 2 gas .2 gas exposure have been executed repeatedly. Yang et al. [2 gas, because of the synergistic effect between rGO and PEDOT. The gas sensor based on rGO and PEDOT nanocomposite under the various concentrations of NO2 gas  nanoparticles utilized the sol-gel method to obtain TiO2@PPy–graphene nanosheet (GN) nanocomposite  when exposed to 50 ppm of NO2 at room temperature. The gas sensor based on RGO-PPy composite decorated by TiO2 indicated a response of 102.2% toward 50ppm of NH3 [PPy is one of the most widely used conducting polymers in different applications due to its high conductivity, facile synthesis process, and great environmental stability . Graphenm of NH3 .2, humidity, NH3, and CO is indicated in 3 exposure when it is decorated with TiO2 nanoparticles [2 is an n-type semiconductor material with a bandgap of around 3.33 eV, which made it useful for sensing materials [2 nanoparticles can be a useful way to enhance sensing performance of rGO/PPy.The investigation of gas sensors based on RGO-PPy composites toward various target gases such as NOarticles . TiO2 isaterials . DevelopPolystyrene (PS)-modified graphene composites were prepared by using the solution blending method ,137,138.2 detection [2 exposure) compared to the pure PTh and graphene which might be attributed to synergistic effects between PTh and graphene [The in situ polymerization technique was used to prepare a hybrid of ethylenediamine-modified, rGO, and PTh and then the as-prepared hybrid was deposited on a flexible PET film to fabricate a sensor for NOetection . PTh attetection ,144. Thegraphene ,146,147.2TPP and graphene which were selected for being versatile, biodegradable, eco-compatible, recyclable (PS) [Joshua Avossa, et al.  designedble (PS) ,149 and −3 ΔR/R mg L−1 and the LOD of the sensor was 22.67 mg/L.Rey Alfred G. Rañola, et al.  investig3 exposure. 3 (1–1500 ppm). As we can understand from the tables and 3, the gas-sensing performance of PEDOT/RGO nanocomposites prepared by in-situ polymerization technique revealed in contrast to other PEDOT/RGO nanocomposites exhibited excellent sensing performance to NO2, and rGO/PPy nanocomposite indicated the highest response of 102.2% under 50 ppm NH3 exposure when it is decorated with TiO2 nanoparticles. Compared to various gas sensors based on graphene and conductive polymer nanocomposites such as graphene/PEDOT, graphene/PPy, graphene/PTh, and so on, graphene and PANi nanocomposite gas sensor shows the highest response for detecting NH3 gas. The enhancement of gas accessibility might contribute to the large surface area of the composite materials and also the combination of materials with various properties can result in a synergistic effect. Incorporating the merits of high conductive graphene sheets with the advantages of conducting polymers has attracted researchers’ attention to tap their novel characteristics because of the synergistic effect between them. The superior electrical properties of graphene materials, including high carrier mobility, and detectable change in their resistance after adsorption or desorption of gases, also contribute to the high sensitivity.The preparation methods and sensing performance of graphene and conductive polymer nanocomposites are discussed in this review paper. The most widely used methods to prepare nanocomposites of graphene and conductive polymers for the application of gas sensors are in situ chemical polymerization. Mixing these two materials exhibited better sensing performance compared to pure graphene and conductive polymers because of the large specific surface area of the nanocomposites, which might be attributed to the anchoring of conducting polymers on the surface of graphene sheets. According to the tables listed, rGO–PANI hybrids loaded on a flexible PET thin film indicated the highest response of 344.2 to 100 ppm NHThe most important mechanism that should be considered in graphene and conducting polymer composites is normally referring to non-interface dependent complementary behavior, which is known as a synergistic effect. A synergistic effect determines when various constituents in a composite material are separately in contact with the gas phase and serve a different purpose that is complementary of the other constituents in a material.The chemiresistors fabricated using the composite of graphene and other conducting polymers to date have received relatively little attention. On the other hand, there are only a few works that have studied the sensing performance of graphene/conductive polymer composites under various gases. Very few works have been reported on new preparation methods of this novel material and their application in gas sensors. The lower limit of detection for the given gas was not reported in most studies.Improving the large-scale production of gas sensors based on graphene/conductive polymer nanocomposites, enhancing the selectivity by functionalizing the sensing layer, and increasing the stability of the active layer should be considered in future studies.


Students are using file sharing sites to breach academic integrity in light of the Covid-19 pandemic. This paper analyses the use of one such site, Chegg, which offers “homework help” and other academic services to students. Chegg is often presented as a file sharing site in the academic literature, but that is just one of many ways in which it can be used. As this paper demonstrates, Chegg can and is used for contract cheating This is despite the apparent existence of an Honour Code on Chegg which asks students not to breach academic integrity. With pandemic led safety considerations leading to increased online teaching and assessment, the paper analyses data relating to how Chegg is used by students in five STEM subjects, namely Computer Science, Mechanical Engineering, Electrical Engineering, Physics and Chemistry. The results show that students are using Chegg to request exam style questions. They demonstrate that contract cheating requests can be put live and answered within the short duration of an examination. The number of student requests posted for these five subjects increased by 196.25% comparing the time period April 2019 to August 2019 with the period April 2020 to August 2020. This increase corresponds with the time when many courses moved to be delivered and assessed online. The growing number of requests indicates that students are using Chegg for assessment and exam help frequently and in a way that is not considered permissible by universities. The paper concludes by recommending that academic institutions put interventions in place to minimise the risk to educational standards posed by sites such as Chegg, particularly since increased online teaching and assessment may continue after the pandemic. This paper reports on the growth of how a single market leading file sharing website has been used for contract cheating purposes. The period of growth coincides with the Covid-19 pandemic and the associated necessary increase in online teaching and assessment within education.when academic lecture materials, notes, assessment tasks, answers, and responses are shared, swapped, and traded over Internet-based sites in fee, free, or barter (credit/exchange) arrangements”. Although student collaboration is often encouraged within an educational setting, a challenge with file sharing comes when students share files owned by a university with commercial providers. These providers then sell materials which they have no ownership claim over to other students. Often a barter system is used, with other students encouraged to upload more materials so that they can themselves get access to other resources and answers. As well as breaching copyright and instructor rights of intellectual property, this also has commercial implications for educational providers. Dixon and George  subjects, offering an analysis over a two-year period with reference to pre and post Covid-19 provision. The paper concludes by recommending that the sector works to address contract cheating through file sharing sites particularly as this relates to Covid-19.Many forms of assessment are susceptible to contract cheating. The literature in this field has revealed that an aggressive industry exists, aiming to implore students to cheat  number of questions posted in 18/19 was 8357 and in 19/20 was 14,578. Table The number of questions asked and answered on 1 March each year was also calculated. Eight thousand two hundred seventy-six questions were posted 1 March 2018 across all five subjects. These were answered 89.96% of the time. Thirteen thousand seven hundred nineteen questions were posted on 1 March 2020 and answered 85.57% of the time. Despite the slight drop in the percentage of questions answered, the raw numbers showed a substantial quantitative increase.Table The average number of questions per day per month was also calculated at a subject level and compared on a month-by-month basis. This showed a striking result. Between September and March, inclusive, the percentage increase never exceeded 32.27% for any of the subjects. Between April and August, inclusive, the smallest increase was 80.08% and the largest increase 343%. Table Figures For example, in Fig. Figure A further analysis considered the average number of questions asked per day in the September to March period and in the April to August period, compared over the 2 years. Between September and March, this showed an overall 12.68% increase between the years of the average number of questions posted per day per month, but between April and August the increase was 196.25%, which is a substantial difference. Furthermore, the average had dropped by 28.92% between the September 2018–March 2019 and April 2019–August 2019 periods, but increased by 87.74% between the September 2019–March 2020 and April 2020–August 2020 periods.Table Although Table Chegg do not provide the facility to trace requests directly back to an individual academic provider, or even a country of origin. On occasion it may be possible to work this out, but the way in which data is shown on the site makes this difficult. For example, some posts contain photos or screenshots of a problem that is likely to have been encountered in a standard textbook. Such standard questions could be in use at many institutions.Many questions list a number of available marks on them. Others appear to contain randomised variables. These are indicators that the questions are likely from online exams. Some questions contain both marks and randomised variables, as indicated by the Physics question example shown in Fig. Students have also been observed posting a series of requests one after another, most often where the questions are multiple choice or short answer format. Figure An interesting consequence of the Covid-19 pandemic is that there are many questions on Chegg whose themes include Covid-19. A selection of terms such as COVID, pandemic and coronavirus were used as search terms across all questions on Chegg from all subjects. In every case, Chegg returned 500 results, which is the limit of the number of questions returned by a search. This indicates that students around the world are being set questions on Covid-19 and that many of them are finding their way onto file sharing sites for third parties to answer on their behalf.This paper has reviewed how a file sharing website popular with students is used to facilitate contract cheating. There are many assessed coursework and exam questions posted and answered every day. The data shows a substantial increase in the number of questions asked and answered in the period from April 2020 onwards, largely matching with the move online of teaching and assessment. Given the number of exam style questions, it appears highly likely that students are using this site as an easy way to breach academic integrity by obtaining outside help.Using the fact that around 85% of questions asked are answered at least once, it is possible to approximate the number of questions answered each year. Based on Table To have a successful and growing business and to deliver a return to its shareholders, Chegg depends on a continual growth in the number of subscribers it has. Based on the growth in the number of questions asked, this also suggests an increase in subscribers and thus the number of students who have access to the answers.The apparent growth in student cheating also matches an increase in the market value of Chegg. Table In an interview, Chegg’s chief executive mentioned that they noticed a “sustainable growth” of the website starting from 15 March 2020 (Gelles Chegg does claim to have an Honour Code in place. In the Honour Code, it is stated that Chegg does not support fraud, cheating or breaches of copyright and suggests that materials may be removed or user accounts terminated if academic institutions contact them to open an investigation. There is little evidence that account termination has happened. In addition, it appears that there is nothing to stop students posting questions online and receiving answers within the time frame of an exam. There does not seem to be any manual approval of requests or periods of delay before questions are put live to be answered. People, including Chegg certified experts, appear to be ready and waiting to answer questions as they are asked. This seems to provide evidence that the Chegg Honour Code system is not working based on the volume of requests for assessed work that have been observed.Some individuals have stated that requests can be made to Chegg if their copyrighted teaching or assessment material is found online Murdoch . This maFuture action in this area is necessary. This includes awareness raising with both staff and students. Using contract cheating services is not victimless and this has to be communicated. Similarly, the messaging needs to provide consistent and clear advice that there are benefits to working with academic integrity and there are risks involved when breaching it. Staff should be encouraged to monitor file sharing sites for their assessments, but this can be difficult when questions are posted as images rather than text. Some form of automated monitoring, with immediate reporting to instructors if their assessments or exam questions appear to be found online, would be a useful development.Further research data could be collected from Chegg, covering more subjects over a longer time period. This investigation has focused only on STEM subjects, which typically have many questions that are mathematical or scientific in nature. This may make this area easier for contract cheating providers to give quick answers for these subjects than it would be for those that are more text based or descriptive. In addition, content analysis of the questions posted would also be useful, but that would most likely require an automated or machine learning based approach. Although it is the market leader, Chegg is not the only file sharing site. It would be instructive to see if the trends identified here extend more widely.Academic integrity breaches are happening and, as the data presented in this paper has demonstrated, such breaches are becoming more common as a result of Covid-19. These breaches do require a continued reconsideration of teaching and assessment methods. Even if face-to-face teaching returns, it is unlikely that this will ever now consistently take the same format it did prior to the pandemic. The genie is well and truly out of the bottle and there is no way to put the stopper back in. The entire academic integrity community, including but not limited to staff, students, academic institutions, quality bodies and commercial providers alike, needs to be ready and prepared to act.


Candida albicans, multidrug-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus biofilms, whereas MediHoney, polyhexamethylene biguanide (PHMB), and benzalkonium chloride (BZK) ointments failed to eradicate all biofilms within 2 hours. We assessed cytotoxicity by exposing L-929 fibroblasts to extracts of each ointment; Trypan blue exclusion was used to assess cell viability, and Alamar blue conversion was used to assess metabolic function. After exposure to PG+CAP and MediHoney, fibroblast viability was 96.23% and 95.23%, respectively (Trypan blue), and was comparable to untreated cells (98.77%). PHMB and BZK showed reduced viability . Metabolic activity results followed a similar pattern. Cytotoxicity of PG+CAP ointment towards erythrocytes was comparable to saline. PG+CAP ointment seems to be safe and can rapidly eradicate microbial biofilm; thus, PG+CAP ointment merits further in vivo testing as a potential antimicrobial wound ointment.Antiseptic wound ointments are widely used to treat dermal wounds that are microbially contaminated. Polygalacturonic acid (PG)+caprylic acid (CAP) is a novel combination that has been shown to eradicate biofilms. We developed a novel PG+CAP ointment and compared the biofilm eradication capability and cytotoxicity of PG+CAP with that of commercially available antiseptic wound ointments. We used a well-established biofilm model to quantitatively assess the eradication of organisms following exposure to the wound ointments for 2 hours. PG+CAP ointment completely eradicated  Antiseptic wound ointments are widely used to treat dermal wounds that are microbially contaminated. These ointments play an important role in inhibiting microbial biofilms because the ointments are broad-spectrum and do not encourage the development of antibiotic-resistant microorganisms. Quaternary-ammonium benzalkonium chloride (BZK) wound ointment was shown to generate an adequate environment for wound healing; it improved cell proliferation and cell activity and suppressed the multiplication of bacteria , 2. PolyStaphylococcus aureus (MRSA), multidrug-resistant Pseudomonas aeruginosa, Candida albicans, Escherichia coli, and Salmonella enteritidis) [As alternatives to both antiseptic and antibiotic ointments, natural plant-based agents have been shown to provide optimal biofilm disinfection without leading to antimicrobial resistance . MediHonritidis) . This stBenzalkonium chloride , polyhexamethylene biguanide , and MediHoney  wound ointments were purchased and used directly, while PG+CAP ointment was prepared in the laboratory as previously described . The oinP. aeruginosa (MDA #118), and C. albicans (MDA #117), as representative hospital-acquired infection pathogens from cancer patients. For testing, the organisms were grown from glycerol stock on trypticase soy agar+5% sheep blood (for bacteria) or on Sabouraud dextrose agar . Each organism was inoculated into Muller Hinton broth and diluted to 0.5 McFarland. Further dilutions were made as necessary for testing.Biofilm eradication testing was conducted using highly virulent clinical isolates of MRSA (MDA #120), multidrug-resistant 5 CFU/mL) and incubating at 37°C for 24 hours. All culture liquid was then removed, and disks were washed for 30 minutes in isotonic sterile saline to remove any remaining planktonic organisms. After washing, disks were exposed to ointments, control ointment base, and control by adding Muller Hinton broth and incubating at 37°C for 120 minutes. After exposure, viable organisms remaining on the surface of the silicone disks were assessed by disrupting biofilm via sonicating the disks in 5 mL of isotonic saline for 15 minutes. The resulting sonicate was serially diluted and quantitatively cultured onto trypticase soy agar+5% sheep blood for Staphylococcus aureus and P. aeruginosa or on Sabouraud dextrose agar for C. albicans. Each ointment for each organism was tested with six replicates. To ensure eradication was complete (no surviving dormant or persister cells) from biofilms for which no viable colonies were recovered following the exposure to ointments, we conducted regrowth experiments by first exposing biofilm-colonized disks to each experimental solution, then rinsing, and subsequently transferring the disks to fresh broth and reincubating for an additional 24 hours. Following the 24-hour regrowth interval, disks were sonicated and cultured as indicated above to determine whether any organisms remaining embedded in the biofilm were still viable.A well-established biofilm colonization model was employed to test eradication of pathogenic biofilms following 2 hours of exposure to different ointments . BrieflyMus musculus) cells were used in our study. Cell culture was performed according to fibroblast protocols as described by Rosenblatt et al. [2 until the cells formed a monolayer (60% confluent); then, a 2% extract of each ointment was added to its corresponding wells and incubated at 37°C with 5% CO2 for 24 hours. In the Trypan blue exclusion test, live cells with intact membranes exclude the Trypan blue dye whereas dead cells do not, and therefore, dead cells are stained with blue cytoplasm [μL HBSS+10% Alamar blue reagent and incubated at 37°C with 5% CO2 for 4 hours. Cell viability (absorbance) was determined at 570 nm using a microplate reader spectrophotometer, and the absorbance for each ointment was compared with that of controls.NCTC clone 929 areolar fibroblast mouse , incubating for 24 hrs, and then counting viable erythrocytes from 1 : 200 dilution in normal saline using a hemocytometer. Results from 5 replicates were collected for each ointment. 2% saline in whole blood was used as a control.U test to compare the performance of comparators. All tests were two-sided with an alpha level of 0.05. p < 0.05 was used to determine significance.To determine whether there was a significant difference between ointments and controls in the assays, the Kruskal-Wallis test was used. Pairwise comparisons were assessed using the Mann-Whitney C. albicans but was not able to fully eradicate biofilms of Staphylococcus aureus and P. aeruginosa. BZK and MediHoney did not fully eradicate biofilms of any of the tested pathogens. For MRSA, PG+CAP was significantly more efficacious than PHMB (p = 0.02), BZK (p = 0.002), and MediHoney (p = 0.002) in eradicating biofilms. PG+CAP eradicated significantly more P. aeruginosa biofilms than did BZK (p = 0.015) and significantly more C. albicans biofilm compared with MediHoney (p = 0.015). No growth was observed in the regrowth experiments for any ointments for which no viable colonies were recovered in the biofilm eradication assay, verifying that eradication was complete.p < 0.05). Results of the Alamar blue metabolic activity assay are shown in p < 0.05). Of the ointments assessed, PG+CAP was uniquely able to rapidly eradicate all representative biofilms without producing significant cytotoxicity relative to nonantimicrobial controls. The conventional antiseptic ointments (BZK and PHMB) were more cytotoxic and less broad-spectrum than PG+CAP. Previous studies reported that BZK was cytotoxic to fibroblasts, keratinocytes, and other epithelial cells . ElectroFibroblasts cells treated with PHMB generated discernable cytotoxicity in our study. These results are consistent with previous studies with PHMB on epithelial cells . MechaniDermal wounds have been reported to exhibit improved healing at acidic pH . The PG+These findings suggest that PG+CAP ointment is both safe and can rapidly eradicate microbial biofilm; thus, PG+CAP ointment merits further in vivo testing as a potential antimicrobial wound ointment with low toxicity for treating biofilm contaminated wounds. In this regard, future ultrastructural analysis of biofilms by electron microscopy following treatment with PG+CAP ointment would also be worthwhile.


Mutations in the gene coding for tau, MAPT, can cause FTLD-tau, directly linking tau dysfunction with disease . Another protein, TDP-43, comprises aggregates which are the primary hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP), and mutations in the gene coding for TDP-43, TARDBP, can cause disease . To model tau or TDP-43 proteinopathies, transgenic C. elegans have been generated that express the full-length human protein pan-neuronally. These worms exhibit significant uncoordinated movement on plates and impaired thrashing in liquid . However, tau- and TDP-43- expressing worms are not paralyzed; they still move their heads and have some motility on the plate  which are not captured in standard crawling or thrashing assays. To assay differences in total activity, we used a WMicroTracker ARENA System . The ARENA captures population level activity data by relying on optical interferometry, which uses a large array of infrared LED microbeams to detect both the movement and position of worms on a culture plate. Disruption of an LED microbeam by worm movement is recorded by repeat scans of the 6-well culture plate, and allows for real-time processing. The software identifies changes in the location of disrupted beams between scans and assigns an activity score based on differences identified between each consecutive scan (Simonetta SH). Both tau- and TDP-43- expressing worms had significantly less activity per minute than N2 . Further, we found the ARENA- assessed activity data recapitulated the relative severity of phenotypes among the strains as measured by motility assays. For example, both CK10 (tau V337M) and CK144 (tau WT) have significantly uncoordinated movement when crawling or thrashing in liquid, with CK144 having worse motility than CK10, due to its much higher burden of total tau protein expressed . Likewise, CK410 (TDP-43 WT) worms have slightly impaired motility compared with N2 when crawling on a plate, CK423 (TDP-43 M337V) are severely uncoordinated, and CK426 (TDP-43 A315T) have the most severe uncoordinated phenotype. The relative toxicities of these strains stem from the effects of the mutations, as TDP-43 protein expression is relatively even among these transgenic strains . Interestingly, the ARENA captures activity of these severely uncoordinated worms that move poorly in motility assays such as crawling on an NGM plate or thrashing in liquid . Therefore, ARENA assessment of aggregate activity may be a more accurate metric for capturing non-locomotor movement of C. elegans that are severely uncoordinated.Aggregates of the protein tau are the hallmark of several neurodegenerative diseases including Alzheimer’s disease, frontotemporal lobar degeneration (FTLD-tau), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Pick’s disease, and chronic traumatic encephalopathy (CTE) . The plate was placed in the ARENA 15 minutes before starting the run to allow worms to acclimate. 14 activity scores were collected per strain over 60 minutes. Statistical analysis was performed with GraphPad Prism 8.All worms used were staged by way of timed egglay, and grown at 16Strains UsedN2 BristolbkIs10  IIICK10 bkIs144  IVCK144 bkIs410  IICK410 bkIs423  IVCK423 bkIs426  IICK426