Public participation in community-organized disaster mitigation activities is important for improving disaster mitigation capacity. With data from 260 questionnaires, this study compared the current status of public participation in model disaster mitigation communities and nonmodel communities in a geological-disaster-prone area. Three community-organized disaster mitigation education activities were compared cross-sectionally. A binary logistic regression was used to analyze the effects of attitude, perceived behavioral control, disaster experience, and other key factors on the public’s choice to participate in community disaster mitigation activities. The analysis results indicated that model communities had higher public participation in two efforts, evacuation drills and self-help skills training, and lower participation in activities that invited them to express their feedback than nonmodel communities. The influence of attitudinal factors on the decision to participate in disaster mitigation activities had a high similarity across community types. The public participation in model disaster mitigation communities is influenced by factors such as subjective norms and participation cognition; the behavior of people in nonmodel communities is influenced by factors such as previous experience with disasters, perceived behavioral control, risk perception, and participation cognition and has a greater potential for disaster mitigation community construction. This study provides practical evidence and theoretical support for strengthening the sustainable development of disaster mitigation community building. The geological environment in Southwest China is complex and susceptible to extreme weather conditions. Coupled with the impact of frequent human engineering activities, geological disasters such as landslides and mudslides have occurred repeatedly, most notably in the Wenchuan earthquake in 2008, which induced landslide disasters in up to 200,000 places . ApproxiIn the study of public participation in disaster prevention and mitigation, Pearce argues that public participation combined with community governance can contribute to achieving sustainable disaster mitigation goals . The botSince 2008, the Chinese government has awarded the title of “National Comprehensive Disaster Reduction Demonstration Community” to communities that meet the requirements of the “Management Measures for the Creation of National Comprehensive Disaster Reduction Demonstration Communities” and pass the audit. China’s comprehensive disaster reduction demonstration communities (hereafter referred to as “model communities”) focus on strengthening the construction of community shelters, stockpiling materials, and enhancing the awareness and capacity of community residents in disaster reduction . Wu et aResearch on the construction of disaster mitigation communities has focused on the evolution of community space, macro-policies, and the qualitative evaluation of disaster mitigation capacity ,17, but In this paper, we used model disaster mitigation communities and nonmodel disaster mitigation communities in Jinchuan County, a geohazard-prone area, to distribute questionnaires and conduct semistructured interviews to investigate the factors influencing public participation in “evacuation drills”, “self-help skills training”, and “opinion expression”. The main objectives of this study are as follows: (1) to investigate the degree of public participation in different disaster mitigation activities in both model and nonmodel disaster mitigation communities, (2) to identify the specific factors influencing decisions to participate publicly in different disaster mitigation activities in different community types and analyze the influence of these factors on public participation, and (3) to provide reasonable countermeasures and suggestions for different communities to improve public enthusiasm for participation and enhance the construction of disaster mitigation communities according to the influencing factors on participation in different disaster mitigation activities.The community-based disaster risk management approach has attracted widespread attention from scholars since 2000, aiming to reduce community vulnerability, formulate disaster mitigation strategies and interventions based on local community characteristics and indigenous knowledge, and improve community resilience and recovery when faced with disaster threats . This apActively implementing disaster risk reduction activities is an important approach in risk education and community preparedness. Witvorapong et al.  found thIn terms of public participation in disaster mitigation activities, most studies have concluded that factors such as risk perception ,35, disaIn the study of individual behavioral decision-making, factors such as individual psychology and social relationships should be considered . The theTo summarize, public participation in diverse community disaster mitigation activities is an important task of disaster risk management at present. Based on previous research, this paper comprehensively selects attitudes, subjective norms, perceived behavior control, risk perception, disaster experience, and participation cognition from the perspectives of psychology, natural environment, and social relations to investigate the influencing factors on public behavior in various disaster mitigation activities. To provide an empirical basis for the targeted improvement of community disaster mitigation plans, a comparative analysis was conducted with public participation in model and nonmodel communities. Jinchuan County is located in the northwestern part of Sichuan Province and the southwestern part of the Aba Tibetan and Qiang Autonomous Prefecture in the transition zone between the Sichuan Basin and the southeastern edge of the Qinghai–Tibet Plateau  How do you conduct disaster risk reduction education activities in your community? (2) How do you think participating in community-organized disaster risk reduction education activities has helped you personally? (3) Do you have any suggestions for mobilizing residents to participate in community-based disaster risk reduction activities? A total of 25 interviewees were recruited for the interviews, including 14 from model communities and 11 from nonmodel communities.The questionnaire consisted of three parts. The first part introduced the purpose and background of the study and the basic demographic characteristics. In the second part, the dependent variables were measured, and the three dependent variables of “evacuation drill”, “self-help skills training”, and “opinion expression” were answered as single-choice questions addressing “whether to participate”. The third section of the questionnaire was the core section, which assessed independent variables such as attitude ,62, subjThe previous methods of questionnaire analysis include linear regression, logistic regression, structural equation modeling, etc. Since the dependent variable is an independent binary variable, this study processed the data using binary logistic regression to examine the relationship between the independent factors and event likelihood . The oddThe logistic regression model takes the following form:The OR can be expressed as follows:i denotes an individual; x denotes the independent variable [The marginal effect can be expressed as follows:variable ,72,73.(1)There were more women than men in the sample size;(2)The age level of the respondents was concentrated in the 46–60 age group;(3)The educational level of respondents in nonmodel communities was significantly lower than that in model communities;(4)In terms of occupation, most respondents in the nonmodel communities were farmers, while respondents in the model communities were mainly farmers and self-employed individuals;(5)The monthly income of respondents in nonmodel communities was generally low, with 65.54% earning less than RMB 1500 per month, while 47.33% of respondents in model communities earn more than RMB 3000 per month.The statistical results of the sample demographic variables are shown in Overall, the range of social groups covered by the respondents in this survey and the sample information were highly representative and conducive to the follow-up study.As shown in p < 0.001, indicating that the collected data were suitable for factor analysis. Principal component analysis and orthogonal rotation were used to extract the common factors with eigenvalues greater than one. The results are shown in The factors with the same characteristics were normalized and simplified through dimensionality reduction processing to preserve the integrity of the information to the maximum extent and provide optimized results for the subsequent analysis . First, t-test was needed to examine the variability in the level of variables between the two types of communities. t-tests for the independent variables between the two communities. The results show that there was a significant difference (Sig < 0.05) in the mean values of each variable between different community types.To investigate the factors influencing public choices to participate in community disaster mitigation activities in different community types, a The mean values of “attitude”, “subjective norms”, and “participation cognition” in the model communities were significantly higher than those in the nonmodel communities. This indicated that the model communities have positive attitudes and higher awareness of participatory disaster mitigation activities and are more likely to be influenced by the community and have a stronger sense of consensus.The mean values of “perceived behavioral control”, “risk perception”, and “disaster experience” are higher in nonmodel communities than in model communities, which indicates that the public in nonmodel communities is more affected by the geological disaster environment, has higher risk perception, and has a higher evaluation of their ability to participate in disaster mitigation activities.Holding other factors constant at the mean level, the evacuation drill activities revealed through the data in The behavioral decisions of residents in both types of communities in the self-help skills training activities were positively influenced by personal attitudes (OR > 1), which indicates that, regardless of the type of community, the public can be 7.4% more likely to participate by maintaining a positive attitude toward this activity compared with a negative attitude. The difference is that model communities are susceptible to the negative influence of two factors, perceived behavioral control and risk perception (OR < 1), which means that if these two factors show an increasing trend, it will lower the likelihood of public participation by 10.4% and 8.0%. Nonmodel communities’ perceived behavioral control and perception of group participation positively influence public participation behavior (OR > 1), indicating that the higher the level of perceived behavioral control and participatory cognition, the more likely it is to increase the level of public participation, with probabilities reaching 12.9% and 8.3%.Attitude has a common positive influence (OR > 1) on opinion expression activities for both types of communities, increasing the likelihood of public participation by 17.3% and 14.2% for model and nonmodel communities. Increased levels of subjective norms and participatory cognition by the public in the model communities could increase their likelihood of participation by 5.2% and 6.6%, respectively. People in nonmodel communities were negatively influenced by subjective norms and disaster experiences, which reduced the likelihood of public participation by 7.6% and 6.5%, respectively, but they were positively influenced by perceived behavioral control, which indicated that it could promote public participation by 18.9%.According to the current state of public participation , the modIt is worth noting that the number of residents participating in “opinion expression” in model communities is less than in nonmodel communities. This implies, on the one hand, that model communities are organized and managed more comprehensively and meticulously and have a higher level of resident recognition of participation mechanisms, activity planning, implementation, and the total organization of mitigation activities. On the other hand, nonmodel communities still have shortcomings in the above aspects, and local people have a higher demand for participation and the active expression of feedback out of consideration for their own safety and the development of local disaster mitigation.(1)Factors influencing the “evacuation drill”According to (2)Factors influencing “self-help skills training”According to the findings, the more positive residents are toward self-help skills training activities, the more likely they are to support public participation. Therefore, regardless of the type of community, policymakers must emphasize the necessity of participation in their daily risk communication. Furthermore, this activity was unaffected by “subjective norms” and “disaster experience,” most likely because, as these skills are eminently in the public’s self-interest, the public is more concerned with acquiring self-rescue knowledge to safeguard their own interests.In addition, an interesting result was found: the higher the perceived behavioral control and risk perception of the model community residents were, the less likely they were to participate in rescue skills training by approximately 10.4% and 8.0%, respectively, while other variables remained constant. This marginal effect result reflects the fact that overconfidence may lead to false competence assessment bias and that fear deters people from taking mitigating measures . This alPerceived behavioral control and participation cognition positively influenced public participation in nonmodel communities, demonstrating that the lower the “threshold” of public participation and the more knowledge regarding participation there is, the stronger the public’s incentive to engage. This indicates that there is still room for improvement in disaster mitigation community construction in nonmodel communities and that a large number of resources are still required to invest in and increase public participation in disaster mitigation, which is consistent with the actual situation of most rural disaster mitigation communities in China.(3)Factors influencing the “opinion expression”Consistent with Asare’s report , the facThe difference is that residents of model disaster mitigation communities are positively influenced by subjective norms and participatory cognition in expression activities, whereas residents of nonmodel disaster mitigation communities are negatively influenced by subjective norms and disaster experience and positively influenced by perceived behavioral control. This demonstrates that participation in model communities has a group effect , implyin(1)Increasing the publicity of disaster mitigation and disaster mitigation activities to strengthen the awareness of residents to participate in risk reduction.(2)Reasonable allocation of community resources for disaster mitigation, strengthening the construction of disaster mitigation environments.Based on the analysis of contributing factors, it is clear that community development in geological-disaster-prone locations must use resources wisely and concentrate on strengthening the disaster mitigation environment in nonmodel communities. For example, social resources should be encouraged to provide technical help and financial support, disaster mitigation education events should be arranged on a regular basis, and the “threshold” of participation should be lowered to allow more residents to participate. In daily disaster preparation, the most recent warnings and activities are distributed via WeChat groups, allowing residents to exchange comments. One-on-one, concentrated interventions are set up to help marginalized persons, particularly those who are severely impacted and have a strong subjective will. To minimize the limiting effects of overconfidence and pessimism, model disaster mitigation communities should focus on the observation and direction of the public’s attitude toward risk status and their ability to master rescue skills throughout the deployment of the “self-rescue skills training” plan.(3)Carrying out “one leads many” community exchange activities and allowing model communities to play a leading role.Communication across communities aids in identifying flaws and gaps within the communities themselves. Regular disaster mitigation communication efforts are carried out with the model community as the core and the neighboring rural communities as the targets of information. This provides a model for other communities to learn from in terms of setting up disaster mitigation activities and motivating people to participate. Organization factors as varied as the structure of the disaster mitigation working group, the development of emergency plans, and the design of disaster mitigation publicity, education, and training activities can all be improved by studying the successful experiences of the model communities.Diversified community disaster mitigation activities encourage public participation and strengthen the community’s catastrophe prevention and mitigation and emergency response capacity through a two-way interaction process. However, the implementation of community disaster mitigation methods must take into account the current degree of community and public participation, as well as the elements that impact the public’s choice to participate in various activities. Therefore, this paper takes “evacuation drills”, “self-help skills training”, and “opinion expression” as examples of community-organized activities and compares model disaster mitigation communities with nonmodel communities to determine what specific factors influence the choice of public participation in disaster mitigation activities and the degree of influence under different levels of disaster mitigation infrastructural support.The research results found that: (1) At present, there is a clear difference in the degree of public participation in disaster reduction activities between model disaster reduction communities and nonmodel communities, with model communities relying on resource support to have a stronger advantage in disaster reduction construction, while residents of nonmodel communities show a higher willingness and demand for participation. (2) Attitude is a key factor influencing public participation in disaster reduction activities, indicating that inducing positive public attitudes toward disaster mitigation activities is an important measure to increase the level of public participation across the board. (3) Community disaster reduction planning should reasonably allocate disaster reduction resources and improve the dynamic adjustment of phases. In the process of building future disaster reduction communities, model communities should make phased adjustments to their activity programs based on community characteristics and feedback from public participation and follow up on the public’s skill acquisition and subjective feelings promptly. The motivation of nonmodel communities’ residents to participate is influenced by the pathways to participation and the risk environment; therefore, decision-makers should focus on improving the resource allocation of nonmodel communities and enhancing the demonstration benefits of model communities.There are still some limitations in this paper. First, the sample size only represents the specific situation of public participation in community disaster mitigation in Jinchuan County, a geohazard-prone area. The public community in other areas with different types or levels of risk may have different preferences affecting the results. Second, this paper explores specific factors that influence public participation but does not dig deeper into the interactions and path relationships among the factors; therefore, they can be further specified, extended, and supplemented in the future. The above issues need to be further discussed in future studies.


Additional morphological and crystal structures were examined and confirmed by high-resolution electron microscopy. Subsequently, the investigations of the optical properties evidenced the high optical absorption (98%) and lower band gap (1.75 eV) for the graphene@WS2 compared to the other samples, with good band-edge alignment to water-splitting reaction. In addition, the photoelectrochemical measurements revealed that the graphene@WS2 (1 wt%) exhibits an excellent photocurrent density (95 μA/cm2 at 1.23 V bias) compared with RHE and higher applied bias potential efficiency under standard simulated solar illumination AM1.5G. Precisely, graphene@WS2 (1 wt%) exhibits 3.3 times higher performance compared to pristine WS2 and higher charge transfer ability, as measured by electrical impedance spectroscopy, suggesting its potential use as an efficient photoanode for hydrogen evolution reaction.Tungsten disulfide nanosheets were successfully prepared by one-step chemical vapor deposition using tungsten oxide and thiourea in an inert gas environment. The size of the obtained nanosheets was subsequently reduced down to below 20 nm in width and 150 nm in length using high-energy ball milling, followed by 0.5 and 1 wt% graphene loading. The corresponding vibrational and structural characterizations are consistent with the fabrication of a pure WS Recently, both computational and experimental studies carried out on WS2 have shown its effective role in catalyzing HER with a relatively good yield [2-like materials, such as vertically aligned MoS2, have shown increasingly exposed edges as active sites for HER electrocatalysis, while the basal plane is catalytically inert [2 performances, it is crucial to select an appropriate catalyst-supporting material that can prevent high-surface-area WS2 nanostructures from agglomerating, enhance electron mobility, and overcome the surface overpotential to improve the overall HER performance. Graphene is the other two-dimensional carbon material that would meet the aforementioned criteria. Due to its high ability in electronic excitation and mobility, its mechanical properties, and its high stability, even at the nanoscale, graphene has received rigorous scientific and industrial attention for a long time [2/g), high electron mobility μe at room temperature , outstanding thermal conductivity (5000 W m−1 K−1), and high electrical conductivity (5:6.4 × 106 S/m), as well as a very low weight. These outstanding proprieties enable graphene to be considered an excellent electrocatalyst support for WS2 nanostructures [Hydrogen fuel is considered a promising source of clean energy that could partly replace fossil fuels at the origin of greenhouse gas emissions. Today, there is a growing universal tendency to focus research and development on green hydrogen production by considering the general ecosystem to lower its costs and make it a more affordable clean-energy source, especially through water splitting (WS) ,2,3,4,5.od yield ,14,15,16ly inert . The incly inert ,19,20. Tong time ,24,25,26ructures ,22.2 nanocomposite as electrodes for improved WS reactions. Next, we conducted a systematic structural characterization and assessment of the optical properties to evaluate the performance of the fabricated samples in photocatalysis-driven WS.In this work, we first produced low-cost graphene@WS3) and thiourea (CH4N2S) powders, were acquired from Alfa Aesar™ . Graphene nanoplatelets were purchased from Sigma Aldrich™ St. Louis, MO, USA. The indium tin oxide (ITO) substrates used in this study are from Lumtec™ , exhibiting a resistance < 10 Ω/cm2. All used substrates were cleaned by immersion in detergent, rinsed successively with acetone, ethanol, and deionized water, and dried under nitrogen flow. WS2 nanosheets were prepared using four processing conditions consisting of various WO3 and thiourea contents until achieving the complete suppression of the oxygen residue and obtaining pure WS2 nanosheets. The initial materials’ contents and the corresponding samples are summarized in the The raw materials, namely tungsten oxide  machine with tungsten carbide container and Zirconia oxide balls  were added to the optimized fabricated WS2 nanosheets (S4), followed by high-energy ball milling at 400 rpm for 1 h. To investigate the different physical properties of the resulting compounds, thin films were prepared on top of various substrates, such as glass, quartz, and ITO. 2 nanosheets from aggregating in the transferring tube. Ethanol was used as the host solution.For the graphene@WS2 with or without graphene, which was poured into a 40-megaliter ethanol container followed by water-bath sonication, as shown in For all samples, the spraying procedure consisted of 0.1 g of a mixture made of WSSubsequently, the structural characterization was carried out using a Bruker™ D4 Endeavor X-ray diffractometer with a 1.54 Å CuKα source, and the vibrational analyses were performed with Raman spectroscopy Renishaw™  using a green laser excitation source (532 nm). The microstructure analysis was performed with a Zeiss™  Gemini 500 ultra-high resolution field emission electron microscope (FESEM) operating at low voltage (1 kV), using an In-lens detector. The crystal structure and the morphology of the obtained nanocomposite were investigated by high-resolution transmission electron microscopy (HRTEM) Cs-corrected Titan from Thermo Fisher Scientific™  operating at 300 kV. TEM samples were prepared on holey carbon Cu grids using drop-casting method. The analysis of optical properties was conducted on a UV-vis-near IR spectrometer V-700 JASCO™  and Fourier transform infrared spectroscopy (FTIR) from Thermo Fisher Scientific™ . The electrical impedance spectroscopy (EIS) and the photoelectrochemical (PEC) measurements were performed using PalmSens4™  EIS electrochemical interface.2 samples are shown in 2 phase of cell constants a = b = 3.15 Å, c = 12.32 Å.The XRD diagrams obtained for the four prepared WS3 structure. This indicates that the reaction of the WO3 with the thiourea was not complete; hence, the resulting WS2 of these samples contained WO3 residue. It is worth noting that the strength of the WO3 residue peak was observed to decrease with increasing thiourea content (from sample S1 to S3). By contrast, the WO3 peak was no longer visible at higher thiourea content as it disappeared for the sample S4. This result suggests that the excess thiourea added to the mixture made it possible to obtain the pure WS2 nanosheets.The XRD diagrams of the samples S1, S2, and S3 exhibit an extra peak at (002) position which corresponds to the WO2 samples. All the samples show common WS2 characteristic peaks, i.e., two strong peaks attributed to E2g1 in-plane and A1g out-of-plane vibrational modes appearing at the 350 and 420 cm−1 positions, respectively. The E2g1 mode involves a displacement of W and S atoms, whereas the A1g mode concerns only the S atoms.3 vibration modes at the 293 cm−1, 675 cm−1, and 836 cm−1 positions, respectively, while the S4 only exhibited the vibration modes E12g and A1g for WS2 occurring at 351 cm−1 and 415 cm−1, respectively. As mentioned above, these results confirm that the CVD reaction was fully completed for the S4 and the oxygen was entirely consumed.Similar to the XRD results, the Raman spectra of the S1, S2, and S3 showed the presence of WO2 samples, and the typical Raman spectra are depicted in 2 peaks, graphene vibrational modes were also obtained for both samples at 1560–1575 cm−1 and at 2647–2700 cm−1 for the G-band and 2D-band, respectively. This confirms the presence of the graphene in the processed graphene@WS2 samples.Furthermore, the Raman spectroscopy was carried out on graphene@WS2 nanocomposite samples, FTIR absorption spectroscopy was conducted on pure WS2, WS2: 0.5 wt% Gr, and WS2: 1 wt% Gr, respectively, as shown in To further screen the presence of the graphene in the processed graphene@WS2 nanocomposites and the strength of this peak is more pronounced for the sample with the higher graphene content.As can be seen, the typical graphene absorption peak is present in the graphene@WS2, WS2: 0.5 wt% Gr, and WS2: 1 wt% Gr, respectively. Both the WS2 nanosheets and the graphene platelets are visible. These samples were further investigated by HRTEM and used for the photoelectrochemical measurements.A general view of the sprayed samples on the ITO substrate is given in 2: 1 wt% Gr. The WS2 nanosheets (dark contrast) appeared to be encapsulated in the graphene nanoplatelets (light contrast), as shown in 2 nanosheets. The quality of the nanocomposite was further verified using HRTEM.2 nanosheets and the graphene nanoplatelets, delimited by the blue box highlighted in 2 materials, as demonstrated by the interplanar distances d(002) = 0.62 nm and d(100) = 0.27 nm, illustrated in the red box in 2 and graphene regions given in 2, as demonstrated by the corresponding fast Fourier transform (FFT) intensity image depicted in The investigation of the optical properties was carried out using an optical spectrometer in the 350–800 nm range. 3 impurities induces a decrease in the optical absorption in the visible region. By contrast, the optimized sample S4 showed a relatively unchanged optical absorption. In particular, it remained stable until it reached the excitons position (around 620 nm), at which point it slightly increased. It is clear that the optimized WS2 sample S4 exhibited high broadband light absorption in the visible region, reaching more than 98% compared to the other samples. Using the Tauc formula (αhυ)n = A(hϑ − Eg), the band-gap energy was obtained, as depicted in As can be seen, samples S1, S2, and S3 exhibited similar optical behavior, consisting of a steady decrease in the optical absorption, which started at 93–97% and hit 80% for S1. This suggests that the presence of WOThe obtained band-gap energies were 1.91 eV, 1.87 eV, 1.82 eV, and 1.8 eV for S1, S2, S3, and S4, respectively. The S4 showed the lowest energy, which was in agreement with the broadband optical absorption performances achieved.2 nanosheets, the optical absorption was also measured for both graphene@WS2 samples, namely 0.5 wt% Gr and 1 wt% Gr, and the results are shown in To evaluate the effect of the graphene’s incorporation on the WS2: 0.5 wt% Gr does not seem to enhance the optical absorption . Then, a linear sweep voltammetry (LSV) and chronoamperometry experiments were carried under standard solar simulator (energy~AM1.5G).In this section, the photocatalytic performances of neat WSE0 ≈ 0.197 V at 25 °C and EAg/AgCl is the applied potential.To extract the potential of RHE, the following Nernst equation was used:2 and the distance between the three electrodes was kept at 5 mm. A Pt fishnet (0.5 cm outer diameter) was used as counter electrode, while standard Ag/AgCl was used as the reference electrode. The LSV scan rate was set to 0.1 V/s along 0–1.5 V range. Prior to LSV experiments, all measurements were stabilized for 200 s under zero applied potential. The results are depicted in For both samples, the active surface is about 1 cm2, which was observed to quickly increase with increasing RHE with respect to the applied potential. Note that the highest current density obtained for the S4 WS2 at high applied voltage was reached by the graphene@WS2 sample at very low applied voltage. Hence, the addition of graphene dramatically enhanced the generated density current, six-folds, which was beneficial to HER. To produce WS reactions, a theoretical potential value of 1.23 V versus RHE is required without considering the surface overpotential and the voltage loss due to electron transport. As can be seen, the S4 WS2 nanosheets showed the lowest photocurrent density, of 17 μA/cm2, at 1.23 V versus RHE over the entire potential range. When the graphene was added, the photocurrent density increased vigorously to 95 μA/cm2. The onset potentials of the S4 WS2 and WS2: 1 wt% Gr nanosheets were 0.61 and 0.52 V, respectively. The cathodic shift in the onset potentials indicated an enhanced charge transport; hence, a higher separation efficiency was obtained, even at low ranges of applied potential.As can be seen in J is the current density, Vbias is the bias potential, and Plight is the light power.Moreover, the applied bias potential efficiency (ABPE) was evaluated using the following equation:2/ITO photoanode exhibited an ABPE of 0.79% at around 0.75 V versus RHE, while the WS2: 1 wt% Gr/ITO photoanode reached 4.11% at the same voltage versus RHE. This increase in ABPE in the graphhene@WS2 sample represented a fourfold-higher performance than that of the pristine WS2 nanosheets. This underlines the beneficial effect of WS2 loaded with graphene on photocatalytic WS reactions.The ABPE equation translates how much the cell device using the processed samples as photoanodes is able to produce ionization current under an external applied voltage at constant solar irradiation. Here, the light power was AM1.5G. The applied potentials were converted into the corresponding potential versus RHE using the Nernst equation. The ABPE findings given in 2: 1 wt% Gr/ITO over time, the transient photocurrent was recorded at 0 V of bias with the light on/off cycles at AM1.5G/cm2, using a monitored mechanical shutter. The results depicted in 2: 1 wt% Gr photoanode was examined at a bias potential of 0 V under AM1.5G illumination. A fast decay occurred for the first 100 s. Subsequently, a plateau was recorded, indicating that the photocurrent had reached a value of 0.4 nA/cm2 over the following 100 s. During this time, the photogenerated electrons were transferred to the Pt counter electrode to boost the HER. Consequently, the generated holes could actively participate in the oxidation process at the photoanode site. In our case, the initiation of the WS experiment induced the accumulation of the photogenerated holes at the photoanode site, since no bias potential was applied. These holes could barely be scavenged by water molecules, and recombination occurred, resulting in a decrease in the photocurrent with time. After about 100 s, the rate of generation and consumption of the holes became constant and the photocurrent is stable [2 NSs and WS2: 1 wt% Gr by evaluating the incident photon-to-current efficiency (IPCE), which gives a good estimation of the number of produced electrons with respect of the number of incident photons. The IPCE was determined by the following expression: IPCE (%) = J × V/incident Power. The obtained IPCE was plotted against the applied potential (V vs. RHE) and depicted in To examine the photoresponse of the photoanode WSs stable . Further2: 1 wt% Gr. Therefore, the incorporation of the graphene dramatically enhanced the IPCE, which exhibited an exponential function profile. This indicates that the graphene provided additional electrons circulating in the photochemical cell, which is further proof of the beneficial effect of graphene in enhancing photochemical reactions.2: 1 wt% Gr photoanode, an EIS experiment was carried out to evaluate its charge transfer capabilities. The EIS was conducted on a three-electrode cell and deionized water electrolyte. A Pt fishnet and Ag/AgCl were utilized as the counter and reference electrodes, respectively. The applied voltage was set to 1 V, with a frequency sweep in the range of 0.01 Hz–100 KHz under visible light irradiation at 100 mW/cm2 of power density. The exposed surface area of all the samples was set to 1 cm2. Nyquist plots of the optimized WS2 and WS2:1 wt% Gr and the corresponding equivalent electrical circuit are shown in To further examine the performance of the WS2 nanosheets (45.8 KΩ) compared to the very low resistance obtained for WS2: 1 wt% Gr (10 KΩ). This result clearly shows that the WS2 loaded with graphene promoted a fourfold better charge transfer compared to the neat WS2 sample. This performance undoubtedly suggests that graphene@WS2 is more suitable for use as a photoanode for HER.The comparison of the EIS measurements with the equivalent electrical circuit indicated the higher resistance of the S4 WS2 NSs and graphene. Our findings demonstrate that processing composite materials based on TMD materials combined with a semimetal achieves four-to-five-times better current density at 1.23 V (V vs. RHE), which is necessary to drive WS reactions and hydrogen-evolution reactions. This contrasts with the findings of a previous study [2/rGO and −0.4 V for neat WS2). These values remain low compared to the theoretical potential of 1.23 V required to achieve WS and HER.In summary, in contrast to previously reported work ,27, the 2 were produced in order to be used as highly efficient photoanodes for hydrogen production via a water-splitting reaction. The successful fabrication of the optimized WS2 nanosheets as well as the graphene@WS2 with two graphene contents was confirmed by several combined techniques, including XRD, Raman and FTIR spectroscopies, SEM, and HRTEM. Our main findings indicate that the sample WS2 with 1 wt% graphene exhibited a broadband visible light absorption reaching 98% and an appropriate band gap of 1.75 eV for water-splitting reactions. These outstanding optical properties led to an enhancement of the photogenerated electrons and to a higher charge transfer, as recorded by the photochemical and electron impedance spectroscopy measurements at ambient conditions. Furthermore, associating graphene with WS2 at only 1 wt% content led to an increase in the current density from 17 to 95 μA/cm2 at 1.23 V versus RHE under AM1.5G illumination with ABPE, which was fourfold higher than the pristine WS2 nanosheets. Hence, the graphene@WS2 could be considered a desirable high-efficient photoanode for hydrogen-evolution reactions.Nanocomposite materials consisting of graphene and WS


In terahertz (THz) wireless systems, graphene shows a tremendous promise for the implementation of miniaturized and reconfigurable antennas due to its unique tunable property. This paper presents a wideband beam reconfigurable directional antenna for THz wireless communication systems. The antenna design concept is based on the Yagi-Uda antenna working principle. The proposed antenna consists of a centre-fed graphene-based driven dipole and three graphene-based parasitic elements on either side of the driven element. These graphene-based parasitic elements either act as directors or reflectors by controlling the surface conductivity of these elements. The surface conductivity of the elements is adjusted individually by applying a bias voltage via the chemical potential of the graphene. The main beam direction of the antenna can be reconfigured by controlling the chemical potentials of the graphene-based parasitic elements. Specifically, the proposed graphene THz antenna reconfigures the main beam into four orthogonal directions  at an operational frequency 1.25 THz. The antenna achieves a directional symmetrical radiation pattern with 14 dBi gain and a front-to-back ratio of 15.5 dB. Furthermore, the proposed graphene THz antenna provides a stable reflection coefficient in four reconfigurable cases and an ultra-wideband of 10-dB impedance bandwidth of 120%. Therefore, this novel design technique of graphene-based ultra-wideband high gain beam reconfigurable THz antenna is promising for THz wireless systems. The THz wireless communications have the advantage of more bandwidth, more directionality, and higher data rate compared to the radio frequency and microwave bands. However, the THz band has a high propagation loss, including molecular absorption loss2. Given the high propagation losses in THz wireless communications, the design of a THz antenna plays an important role since THz antennas of high directionality at both transmitter and receiver can compensate for propagation loss. Recently, several antenna designs at THz frequency have been reported in the literature15. However, conventional metal is no longer suitable due to a decrease in conductivity and skin depth in the THz band16. On the other hand, the nanomaterial graphene is a promising candidate for the implementation of THz miniaturized antennas due to the propagation of surface plasmon polaritons (SPP) waves in the THz regime16. Specifically, graphene has gained momentum for reconfigurable THz antennas due to its inherent tunable high conductivity3 . Recently, reconfigurable antennas based on graphene material at THz band have been widely explored17.The use of the terahertz (THz) band, i.e., frequency ranging from 0.1 to 10 THz, has a great interest in wireless communications due to large bandwidth and high data rates20. In the classical Yagi-Uda antennas, the reconfiguration is achieved by employing the switches on the parasitic elements. However, this conventional switch mechanism is not suitable in the THz band. The insertion of switches in THz implementation can increase the complexity of the antenna structure. By exploiting the tunable dynamic conductivity of graphene at THz, few radiation pattern reconfigurable antennas have been designed23. These antennas have dynamic radiation patterns that can be reconfigured, but the adjustable range for the radiation beam is limited.Yagi-Uda antenna is a well-known antenna design for the implementation of pattern reconfigurable antennas24. However, the design process of a graphene-based Yagi-Uda THz antenna is more complicated. In21, the antenna only reconfigures the radiation beam from 24, the authors designed a complicated structure for a reconfigurable four-beam antenna using the Yagi-Uda antenna concept with metal as radiator and graphene as switches for reconfiguration. A design for a switched beam graphene THz antenna using Yagi-Uda concept has been provided in25. In this work, each parasitic element consists of three different graphene strips and are separated by a small distance of 500 nm, which increases the complexity in the antenna structure. The conductivity of graphene strips of each parasitic element adjusted to make the overall length of the parasitic element larger/smaller than the length of the excited dipole, and hence act as a reflector/director of the antenna structure. The bandwidth information of these beam reconfigurable antennas is not available in most of the literature. However, the 10-dB impedance bandwidth of the four-beam reconfigurable antenna in24 and25 are 10% and 42%, respectively. In26, multi-beam reconfigurable antenna based on graphene at 1.243 THz achieved 10-dB impedance bandwidth of 10.5%, and the gain of 6.5 dB with a 12.1 dB front to-back ratio. A beam-scanning seven-element quasi-Yagi-Uda antenna based on hybrid metal-graphene materials is deflected from 27. An array of graphene-based Yagi-Uda antennas is reported in28, which consists of four identical Yagi-Uda antennas, reconfigures the radiation beam from The Yagi-Uda antenna concept has been used to design graphene-based reconfigurable pattern THz antennasWe propose a simple structured wideband beam reconfigurable THz antenna using novel graphene nanomaterial. The antenna design concept is based on the Yagi-Uda antenna principle. The antenna consists of graphene-based driven dipole and parasitic elements.We design a graphene-based Yagi-Uda reconfigurable antenna by using the electromagnetic (EM) simulator CST Studio Suite and provide the simulation technique for the EM modelling of graphene elements and the beam reconfiguration for the proposed antenna structure.We investigate the performance of the proposed antenna by controlling the chemical potential of the graphene-based driven and parasitic elements. The antenna’s radiation direction is reconfigurable, covering a Furthermore, the experimental feasibility and the required bias voltage to enable the beam reconfiguration of the proposed antenna is discussed.In comparison to previous works, in this report, we present a novel and simple way to design a graphene Yagi-Uda antenna with wideband and beam reconfiguration capability in the THz band. In this work, each parasitic element is a single graphene strip of dynamic conductivity, which makes its implementation simpler than previous works. Moreover, the proposed antenna provides wide bandwidth of 120% and high directivity of 14 dBi compared to previous works. The antenna is capable of reconfiguring its radiation pattern, covering a 29j is the imaginary unit, e is the electronic charge, T is the temperature, To evaluate the proposed graphene-based THz antenna structure, it is essential to model the conductivity of graphene at THz frequencies. According to Kubo formalism, the surface conductivity of graphene in the THz band can be approximated asE can be approximated as30.The conductivity of graphene is strongly dependent on the chemical potential 31t is the thickness of the substrate, and Moreover, the chemical potential parameter of graphene can be adjusted by applying a bias voltage to the graphene layer, which can be approximated asThe bias voltage ted from  as4\docu32. For instance, in the present case, the chemical potential E = 9.05 kV/cm. With the increase in the applied bias voltage, more charge is induced on the graphene element, which in turn increases the chemical potential. The tunable chemical potential of graphene enables the different states and reconfigurations in the graphene-based THz antennas. In the present work, the tunable conductivity of graphene via chemical potential is used to reconfigure the main beam into different directions.In the design of the proposed antenna, the chemical potential A graphene-based Yagi-Uda reconfigurable antenna with four orthogonal beams at THz band is investigated. The design of the proposed antennas is based on the principles of the Yagi-Uda antenna. The three-dimensional (3D) view, cross-sectional view, and top view of the proposed graphene-based Yagi-Uda antenna are shown in Fig. mentclass2pt{minimIn the proposed graphene-based Yagi-Uda THz antenna, the graphene-based parasitic elements either act as directors or reflectors by controlling the surface conductivity of these elements. The surface conductivity of the elements is adjusted individually by applying a bias voltage via the chemical potential of the graphene. The chemical potential of the graphene strip determines its conductivity and hence its active charge concentration region or electrical length. The reflectors are the graphene parasitic elements with higher chemical potential of graphene strip, which means a larger electrical length. The directors are the graphene parasitic elements with smaller chemical potential, which means a smaller electrical length. The dependency of graphene conductivity on the chemical potential parameter enables the reconfiguration in the graphene THz antenna. In the present work, the chemical potential entclass1pt{minimaD1, the element 1 is the driven dipole, elements 2, 3, and 4 are directors and the element 5 is the reflector. Similarly, the element 8 acts as the driven, the element 12 as the reflector and elements 9, 10, and 11 as the directors for mode D2; the element 1 as the driven, the element 2 as the reflector and elements 5, 6, and 7 as the directors for mode D3; the element 8 as the driven, the element 9 as reflector and elements 12, 13, and 14 as the directors for mode D4. The four modes with the chemical potential values of graphene antenna elements are listed in Table The proposed THz antenna consists of two graphene-based driven dipole elements (1 and 8) at the middle and 12 graphene-based parasitic elements on either side of the driven element. In addition, 2, 3, and 4 are three parasitic elements on top; 5, 6, and 7 are three parasitic elements on bottom; 9, 10, and 11 are three parasitic elements on left side; 12, 13, and 14 are three parasitic elements on right side. Feeding has been provided at the centre of driven elements 1 and 8. Two driven dipole elements 1 and 8 are placed in crossed manner at the middle, whereas as three parasitic elements are placed with equidistant in top, bottom, left and right side . The proposed graphene THz antenna operates in four different modes and provides four orthogonal beams. For each working mode, one driven element, one reflector and three directors are required. In mode The graphene properties and the dimensions are chosen for the antenna to operate at 1.25 THz frequency. The The normalized radiation patterns of the antenna in four working mode is shown in Fig. 33. As a result, in order to achieve high data transfer rates, THz systems require devices with multiple antennas and beamforming capabilities. The proposed multibeam antennas are expected to meet this requirement. In traditional low-frequency smart antennas, complex signal processing is required to make a decision for the switched-beam antenna as to which beam to access at any time. In contrast, in the proposed THz antennas, the complexity is reduced significantly because only a voltage change is needed for steering the beam direction. The proposed THz antennas can act as promising candidate for THz communication systems due to its orthogonal beam patterns.The major concern in THz communications is the significant path loss effects on account of molecular absorption35. This kind of environments are enabled by reconfigurable intelligent surfaces, a novel class of planar materials that combine the physics of meta-materials with the connectivity and deployment requirements of the Internet of Things. The unique plasmonic and electronic properties of graphene enable efficient reconfigurable intelligent surface at THz37. The user-side multibeam THz antennas and the environment-side intelligent surfaces can build a promising THz wireless system.Recently, intelligent wireless environments have been proposed as promising smart environments that can make capable of sensing and manipulating wavefronts emitted by user devicesA graphene-based wideband beam reconfigurable directional antenna for THz wireless communication system is proposed in this work. The concept is based on the working principle of the traditional Yagi-Uda antenna. The graphene-based parasitic elements either act as directors or reflectors by controlling the surface conductivity of these elements. The surface conductivity of the elements is adjusted individually by applying a bias voltage via the chemical potential of the graphene. The tunable conductivity behaviour of graphene is used to create orthogonal beams. The performance of the proposed antenna is controlled by the chemical potential of the graphene-based driven and parasitic elements. The antenna is reconfigured in its radiation direction, covering a 36038. In the EM simulator, the graphene element is modelled as a thin resistive sheet with surface impedance T. The thickness of graphene strip 39. In the present work, room temperature T = 300 K, Fermi velocity 40. The relaxation time of graphene is computed as 3. The discrete face port (fed by a 50 ohm source) is considered for the excitation of the antenna structure in the CST Studio Suite EM simulator. For mode The CST Studio Suite EM simulator is used to model the graphene and validate the proposed designed antennaE = 9.05 kV/cm. With the increase in the applied bias voltage, more charge is induced on the graphene strip, which in turn increases the chemical potential. The bias voltage of 1.8, 2.7, and 3.6 V are required to enable the beam reconfiguration of the proposed antenna structure.In the EM simulator, the changing of chemical potential parameter enables the reconfiguration in the graphene THz antenna. To achieve the different modes in the proposed graphene THz antenna, the chemical potential of graphene elements varies from 0.4 eV to 0.8 eV. The variation of chemical potential is achieved by applying different bias voltages to graphene strips. In the present case, the chemical potential 41. On top of the polysilicon layer, a silicon dioxide layer of thickness 2 µm can be spin-coated and then, it should be heated at 300 °C for one hour. The chemical vapour deposition grown graphene strips can then be transferred onto the silicon dioxide layer. Graphene conductive ink is also promising for printed electronics. The antenna can also be fabricated using graphene ink on the silicon dioxide substrate.The feasibility of the fabrication of the proposed antenna structure can be explained with the help of Fig. 43. The different bias voltages enable the different chemical potential on graphene, leads to control of surface conductivity in graphene sheets. The tunable conductivity nature of the graphene elements in the proposed antenna enables beam reconfigurability. The modulation of graphene conductivity experimentally can also be achieved by a photoexcitation process41.The reconfigurable capabilities of the proposed graphene THz antenna structure can be demonstrated experimentally by independent control of each graphene strip through different biasing gates


Vaccine-hesitant persons who inject drugs are at increased risk for several vaccine-preventable diseases. However, vaccination rates among this population remain low. While syringe services programs (SSPs) are places where persons who inject drugs feel comfortable accessing services, few offer vaccination services. This study describes facilitators and barriers to vaccination at SSPs.We used convenience sampling to conduct semi-structured, qualitative in-depth interviews with 21 SSPs in the USA from June to August 2021. Interview questions asked SSPs about their perceptions, priorities, barriers, facilitators, and the effects of partnerships and policies on vaccine administration. We used deductive thematic analysis to identify the main themes.n = 8) SSPs offered vaccinations, and thirteen (n = 13) did not offer vaccinations. Most SSPs believed offering vaccination services was important, although addressing SSP participants’ immediate needs often took precedence. Staffing, physical space, and logistical issues were the most common barriers to vaccine administration reported by SSPs, followed by SSP participant-related barriers. Facilitators of vaccine administration included access to a tracking system, partnering with agencies or other organizations providing vaccines, and having a licensed vaccination provider on-site. Partnerships provided SSPs opportunities to expand capacity but could also restrict how SSPs operate. Recommended policy changes to facilitate vaccine administration included subsidizing the cost of vaccinations and addressing restrictions around who could administer vaccinations.Eight (Increasing the availability of vaccination services at SSPs requires addressing the varying capacity needs of SSPs, such as tracking systems, licensed vaccinators, and free or low-cost vaccination supplies. While these needs can be met through partnerships and supportive policies, both must consider and reflect cultural competence around the lived experiences of persons who inject drugs. Persons who inject drugs are at increased risk for several vaccine-preventable diseases, including hepatitis A , hepatitDespite elevated risks of viral hepatitis among people who use drugs and the availability of effective vaccines, recent studies documented vaccination rates of 32–51% for hepatitis A and 35–56% for hepatitis B among this population –12. Accen = 105), 44% offered any vaccinations on-site; among those, the most commonly provided vaccines were COVID-19 (91%), hepatitis A (76%), influenza (73%), hepatitis B (70%), and tetanus (57%)  stuff out” (NV-387).Despite being a priority, many SSPs recognized specific organizational challenges to vaccine administration. Capacity and logistical issues were the most common barriers to vaccine administration reported by SSPs, followed by participant-related barriers.“I think, well, one of the things is, is there a nurse available? Because it's not ideal to talk to somebody and counsel them and get them excited about whatever service it is, including vaccinations. And then, "Oops, nobody's here. You have to come back another time" (V-651).Over half the SSPs cited limited capacity as a barrier to vaccine administration. Some capacity issues included not having enough physical space to administer vaccines, inability to store or transport vaccines, and no or limited staff qualified to administer vaccines and complete vaccine-related tasks like data entry, tracking, and follow-up. As one SSP explained, they did not want to advertise a service to participants if no one was available to provide it.“What's been difficult is we've not been able to offer consistency. And I think that's hard. Usually, we like to keep things very consistent, just so our participants know what they can count on” (V-855).Most SSPs we spoke to had only one or two full-time staff. Limited staff created the additional problem of time management. Several SSPs struggled with making time to administer vaccines and the associated tasks, such as assessing participants’ needs, accessing records, providing education, data entry, and addressing participants’ vaccination questions. In addition, SSPs with vaccine programs noted that these challenges often created delays or rescheduling of vaccine events, making it tough to offer vaccination services consistently."Honestly, it's just about getting our participants to sit down and discuss that as a need…So I think the biggest barrier is that we don't have that face-to-face interaction with our participants as much as we would like to" (NV-861).In addition to staffing, many SSPs reported participant-level barriers, including a lack of participant demand for vaccinations and vaccine hesitancy specific to COVID-19 vaccinations, which created challenges for vaccine administration. Several SSPs believed that having more staff would allow them time with participants to stress the importance of vaccinations.We asked the SSPs we interviewed about facilitators for initiating or scaling up vaccination services. Most SSPs not offering vaccine services believe having access to a system to track and look up a participant’s vaccination history would make it easier to offer vaccinations. However, among those SSPs, a couple had concerns about using a vaccine tracking system. For example, one SSP worried about participant acceptance of sharing personally identifiable information linking them to an SSP. Another SSP was unsure if access to such a system would assist their ability to offer vaccines because of their staff's lack of familiarity with navigating a tracking system.“Having a tracking system would allow us to create a more targeted approach to who would most likely get a vaccine. And it would probably also help us identify clients who have already been vaccinated” (V-198).More than half of the SSPs without vaccination programs said they would use a tracking system to verify which patients were vaccinated and who needed vaccinations. Several SSPs said they would use this information to tailor their approaches and create better messaging for participants around vaccinations and other medical needs. One SSP believed such a system would allow them to keep track of some aspects of patients' medical histories, especially those who are unstably housed and often have incomplete or nonexistent medical records.Regarding tracking, we asked SSPs if they believed clients would be concerned about their anonymity. A few thought it could be problematic if the client felt their vaccine record would link them back to an SSP. However, most SSPs did not believe concerns over anonymity to be a substantial barrier, especially if the SSP offered or was co-located with a place that offered other services.Half of the SSPs without vaccination programs thought partnering with agencies or other organizations currently providing vaccines would help make it easier to start offering vaccinations to their participants. Most SSPs who mentioned partnerships wanted to partner with a medical facility, community clinic, or another SSP. The remaining SSPs desired to partner with local health departments."I don't think [our staff is] super comfortable talking about vaccinations or immunizations with our clients just because they don't know much about them… It scares people to talk about it if they're not nurses or don't give the vaccine. So, if they had more information on how to provide or offer them, they could maybe do that" (V-830).About a third of SSPs without vaccination programs believed having a licensed healthcare provider on-site would allow them to initiate a vaccination program. A similar number of SSPs said funding for advertising, health promotion, and infrastructure  would facilitate their ability to start a vaccination program. Other facilitators included staff training and staff buy-in.For SSPs currently offering vaccine services, most thoughts increased capacity  would make it easier to scale up their vaccination programs. A few SSPs offering vaccination services mentioned funding to promote vaccination services to the community better and incentivize participants. Example incentives included food, money for transportation, and essential need items . Staff training to address vaccine hesitancy among participants and community education to combat stigma around SSPs were also described as facilitators.[The health department] provides all the supplies, the syringes, and safe-to-use supplies. And then, we supply the supplies they cannot purchase with their money. Because we aren't a health department, we can take a few more risks to distribute things like glass pipes or bleach that they can't. So, we come together to provide the items at the SSP and services" (V-911).Most non-health department SSPs we spoke to have a relationship with their local health department; however, their partnerships ranged from nominal, such as a referral source for participants, to extensive. Almost all SSPs with vaccination programs obtained their vaccines and vaccine-related supplies from the health department. The benefits of partnering with local health departments included access to funding, and physical storage space, staff with clinical training, referrals to needed services, and training opportunities for their staff. Several SSPs explained how their partnerships with the health department allowed them to construct a network of services for their participants."[F]inding the time to network is very difficult to be able to, 'Hey, this is what we do. We're wondering if we could partner with you in some way'. It's time-consuming. And as far as what we would need is maybe some soft introductions, even if it's just an email introduction to get something going without us having to do our whole spiel, that would be great" (NV-232).One SSP noted that while they were aware of the benefits of partnering with local health departments, some smaller, low-capacity SSPs lack the time and ability to establish these partnerships."For the most part, [our relationship with the local health department] is just surface because of what my SSP stands for and why we haven't jumped on some public health grants. First, we are very concerned about harm reduction being co-opted and medicalized. Those with grassroots organizations must ensure that those working in SSPs have lived experience. They know the stigma of different cultural aspects and are familiar with the drug culture and our participants" (NV-374).Despite the stated benefits of partnering with local health departments, a few SSPs discussed their concerns with partnering. For example, several SSPs expressed concerns about partnering staff lacking the cultural competence to work with SSP participants and their potential to further stigmatize or mistreat them because of their drug use."We used to [partner with the local health department], but not so much anymore. The health director changed. And then the sheriff changed, there was someone at the health department who did not like people who use drugs and that caused animosity between her and me, and it ended up dissolving" (NV-561).Other SSPs were leery that health departments would impose rules around what and how services are offered. One SSP shared how their funding, services provided, and policies were affected by changing administration politics.“I think just the reimbursement, whatever it is, the Medicaid or Medicare, or both, reimbursement for hepatitis A is a challenge because we only have a limited supply of those free Hep-A vaccines” (V-651).During our interviews, we asked SSPs if there are local or state policies or legislation that impacted their ability to provide vaccinations. Almost half of the SSPs identified jurisdiction-specific policies requiring that only a licensed healthcare provider could administer vaccines as a barrier to initiating or scaling up their vaccine programs. One SSP explained how the lack of Medicaid reimbursement for hepatitis A vaccines presented challenges for participants with Medicaid coverage.“I wouldn't say that any policies make it difficult, especially not at the state level. Locally, I would say our biggest barrier is more attitude towards the SSP program, [and] participants in the SSP program that make it difficult for us to more publicly advertise kind of the services that we're offering” (V-198).Several SSPs clarified that negative community attitudes toward SSPs, not policies, limited their ability to advertise for their vaccination program and other services they offered.“I think just offering vaccinations for free to all individuals would be the easiest and the most meaningful legislation. It's difficult sometimes to get vaccines to people if they don't fall in certain categories” (V-830).A few SSPs proposed policy or legislative changes to support their vaccination programs. More than one SSP suggested eliminating user fees for all adult vaccinations.The remaining proposed policy or legislative changes included removing barriers around who could administer vaccines and getting full reimbursement for hepatitis A vaccines from Medicaid.SSPs are an essential public health partner for reducing vaccine-preventable diseases among persons who inject drugs. These qualitative interviews with 21 US SSPs identified limited personnel and space capacity, logistical issues, and participant concerns as barriers to vaccination programs at SSPs. Trusted partnerships with organizations providing vaccines, availability of an on-site, licensed vaccinator, and access to a vaccination tracking system were identified as facilitators of vaccination programs at SSPs. Overall, SSPs supported vaccinations and recognized the importance of vaccinations for improving the health of persons who inject drugs; however, SSPs face fundamental challenges in initiating vaccination services for participants. Our interview project identified three opportunities for public health partners to support SSPs in starting or scaling up vaccination services—building capacity for staffing, space, and equipment, providing access to immunization information systems, and enhancing culturally competent partnerships.To expand vaccination services and provide consistent vaccination access, SSPs need support to increase staffing, space, and equipment capacity. Efforts to increase the number of SSP staff, hire staff who can administer vaccinations, and enable SSPs to provide vaccinations on-site would help make staff more available to engage in vaccine conversations. To address the challenges of hiring licensed vaccinators, jurisdictions could review local regulations and expand the types of providers eligible to administer vaccinations with appropriate training and supervision. Health departments can share existing vaccination training resources with SSPs, which would make it easier for SSP staff to engage participants in vaccine conversations. Addressing participants’ competing priorities by offering food, transportation, or housing resources and reducing the steps needed to receive vaccination would help participants engage in meaningful vaccine conversations. However, understanding the feasibility and effectiveness of direct incentives, like financial incentives, deserves further study. CDC supports SSPs through cooperative agreements to support –31 COVIDOur findings highlighted heterogeneity in the provision of on-site vaccination services. Accessibility of vaccinations depended on the hours of operation, the number of staff, and whether licensed vaccinator staff were available part-time or full-time. SSPs noted the importance of consistency when offering services, including vaccination services. Provided with adequate staffing resources, SSPs will also need support to incorporate vaccination screening and services into regular workflows. Providing SSPs with access to immunization information systems (IISs) will assist SSPs in tracking vaccination histories and tailoring vaccination services. Some SSPs described reviewing vaccination status before participant visits or using a cover sheet to remind providers to ask about vaccination. Improving access to IISs could help SSPs use limited staff time and improve consistency in offering vaccinations.Most SSPs used partnerships to create a network of services for their participants but also for their sustainability and growth, providing many SSPs with funding, staff, physical space, training, supplies, and capacity building. The trusted relationship between SSP staff and participants is key to increasing vaccine acceptance among persons who inject drugs. Expanding partnerships between SSPs and public health and healthcare agencies should not compromise trusted relationships between SSPs and their participants. Studies of SSPs  during tThis report is subject to limitations. The qualitative interviews were conducted during the first 12 months of COVID-19 vaccine availability; recent COVID-19 experiences informed many responses. Although we interviewed a mixture of SSPs with and without vaccination services and from a wide geographic range, the perspectives in the interviews might not be representative of all SSPs in the USA.Federal, state, and local public health partners can support SSPs to initiate or scale up vaccination services for persons who inject drugs by supporting the expansion of SSP capacity, providing access to immunization information systems, supporting operational environments conducive to quality partnerships, and addressing the stigma around injection drug use.Despite the great need for access to vaccinations among persons who inject drugs, only a few SSPs offer vaccinations on-site. We found that increasing the availability of vaccination services at SSPs requires addressing the varying capacity needs of SSPs, such as tracking systems, licensed vaccinators, and free or low-cost vaccination supplies. Many of these needs can be met through SSPs developing partnerships with existing vaccine providers and supportive policies that lower barriers for SSPs wanting to provide vaccination services. Critical for both success and sustainability, partnerships and policies must consider and reflect cultural competence around the lived experiences of persons who inject drugs.


However, in addition to being costly and time-consuming, existing strategies for synthesizing sulfides/graphene composites often involve complicated procedures. It is therefore essential to develop a simple yet scalable pathway to construct sulfide/graphene composites for practical applications. Here, we highlight a one-step, template-free, high-throughput “self-bubbling” method for producing MoS2/graphene composites, which is suitable for large-scale production of sulfide/graphene composites. The final product featured MoS2 nanoflakes distributed in three-dimensional macroporous monolithic graphene. Moreover, this unique MoS2/graphene composite achieved remarkable electrochemical performance when being applied to Na-ion battery anodes; namely, excellent cycling stability (474 mA h g−1 at 0.1 A g−1 after 100 cycles) and high rate capability (406 mA h g−1 at 0.25 A g−1 and 359 mA h g−1 at 0.5 A g−1). This self-bubbling approach should be applicable to delivering other graphene-based composites for emerging applications such as energy storage, catalysis, and sensing.Layered metal sulfides (MoS 2 composites for improved performances in sodium-ion batteries.A single-step, template-free, high-throughput synthesis method is developed to produce graphene/MoS Unfortunately, due to the large volume change and/or the sluggish kinetics during charge/discharge cycles, these materials delivered either low reversible capacity or poor cyclability.12 Consequently, layered metal sulfides  have also been explored as anode materials in NIBs due to their unique structural characteristics.13 For example, molybdenum sulfide (MoS2), stemming from its large interlayer spacing  and high capacity for hosting foreign species, has been recently highlighted as a possible candidate for anode material in NIBs.14–19 According to the intercalation and conversion reaction between one MoS2 molecule and four Na+, the theoretical capacity of MoS2 is as high as 670 mA h g−1.20Sodium-ion batteries (NIBs) have been proposed as promising alternatives to lithium-ion batteries (LIBs) in the megawatt- and kilowatt-scale energy storage scenarios  in addition to be costly and time-consuming.28 Another issue with existing MoS2/graphene compositing methods is that some of them do not ensure the intimate contact between MoS2/graphene interfaces, an unfavorable condition for electrochemical applications (charge-transfer process).26 Finally, most of the present MoS2/graphene compositing methods are faced with the issue of low yield, ranging from several tens to hundreds milligrams of powders under laboratory conditions.To improve the electrical conductivity and enhance the structural integrity of MoS2/graphene composite. Our method is cost-effective, simple and scalable. The synthesis utilizes the thermal decomposition of solid precursor to generate MoS2; meanwhile, the released gas from the decomposition reaction blows premixed, melted glucose into crowded bubbles, which then evolve into graphene structures during annealing. The final product is microscopically featured as highly crystalline MoS2 nanoflakes distributed in three-dimensional (3D) macroporous monolithic graphene. With the additional assistance of intimate interfacial contacts between MoS2 and graphene, our composite demonstrates considerably improved electrochemical performance when compared with those of conventional MoS2/graphene composite upon application in NIBs. It is expected that such a unique MoS2/graphene composite should hold potential in promoting the development of practical MoS2 anode in NIBs, while the straightforward self-bubbling method could offer the opportunity in producing MoS2/graphene composites in industrial scale as well as synthesizing other advanced graphene-based composites.Herein, we report a single-step, template-free, high-throughput “self-bubbling” method for synthesizing MoS2 composite in this work. Empirically, thermal decomposition of (NH4)2MoS4 in inert atmosphere leads to MoS2 while releasing a considerable amount of gases.42,43 Results from our carefully conducted thermogravimetric and differential scanning calorimetry (TG/DSC) analysis for (NH4)2MoS4 decomposition in flowing Ar 2MoS4 (as MoS2 source) and glucose (as carbon source) with the setup of a two-stage annealing sequence to produce graphene/MoS2 hybrid, as shown in 4)2MoS4 remains solid inside it. Sequentially, during the second stage (from 200 to 1100 °C), (NH4)2MoS4 decomposes into MoS2 and crystallizes while the released gas species  blow the melted glucose to form crowded bubbles with ultrathin walls, which are then graphitized into 3D graphene networks at high temperature . With this simple approach, a rational nanostructure consists of MoS2 and graphene was obtained (hereafter abbreviated as MoS2@G hybrid). Besides, our approach also allows the MoS2/graphene ratio in the final product to be expediently tuned by using different ratios of (NH4)2MoS4 and glucose as precursors for various potential applications . The advantages of such novel approach include low cost, high flexibility, easy operability and excellent scalability. The complete annealing program is presented in Inspired by these findings, we started with a mixture of (NH2@G hybrid. The single production of the MoS2@G hybrid under our laboratory condition is up to ca. 1–2 g when a 1-inch (diameter) tube furnace was used, and the product is foam-like black solid 45,46 and provides a number of advantages such as excellent mechanical stability, high surface area, and effective avoidance of the graphene restack.The effectiveness of our approach could be fully confirmed by systematic microstructural analysis of the end-product. Firstly, microscopies were involved to reveal the morphological characteristics of the MoSinset of . An optiinset of  manifestinset of  suggest inset of  further 2 content. Transmission electron microscope (TEM) images in in situ experiment22), with a lateral size of 50–100 nm and thickness of 5–10 nm. As expected, the selected area electron diffraction (SAED) pattern in 2 structure (JCPDS no. 37-1492) while the bright diffraction rings reflect high crystallinity  planes) and interlayer distance of graphene (0.34 nm for (002) planes) as shown in the HRTEM images  can be identified throughout repeated observations. It should be noted that MoS2 structure with expanded interlayers is commonly considered to be highly beneficial to improve its electrochemical performance  for battery applications.20,27 In short, the above results consistently showed that the sample from our one-step self-bubbling approach was MoS2 nanoflakes distributed in macroporous few-layered graphene, in accordance with our original design. For comparison purpose, we also prepared pure MoS2 samples via the same process without glucose and the final product is mainly irregular microsized flakes .Our results also show that the graphene walls are decorated with nanosized particulates in the SEM images, most likely the result of the MoSM images , a favorM images , a sligh2@G hybrid. Concerning the chemical states of Mo and S in the product, 2 and MoS2@G hybrid, with their C 1s peak referenced at 284.8 eV. The presence of MoS2 with Mo and S elemental ratio of ∼1 : 2 can be identified for both samples, besides the prominent carbon component in the MoS2@G hybrid. The insets in 2@G hybrid, which are the S 2p, Mo 3d and C 1s regions. The Mo 3d possesses two peaks centered at 229.6 and 232.8 eV, in association with the doublet Mo 3d5/2 and Mo 3d3/2 for Mo4+ ions. Another group of peaks, ascribed to the S 2p3/2 and S 2p1/2 orbital of divalent sulfide ions (S2−), are observed at 162.4 and 163.7 eV, respectively. All these results are well consistent with the reported values for MoS2.25,47 The existence of Mo, S and C in the MoS2@G hybrid was also verified by the electron energy-loss spectrum (EELS), as shown in 2@G hybrid (inset in 2-bonded atoms) as well as a clear σ* step , suggesting the high crystalline nature of graphene in the hybrid.30,48Subsequently, spectroscopic characterizations were employed to further explore the microstructural features of the MoSinset in  presents2 and MoS2@G hybrid match with 2H molybdenite; however, the diffraction peaks of the MoS2@G hybrid are much boarder than those of pure MoS2, a result of the fine MoS2 crystalline size. Notably, the peak of (002) planes for the MoS2@G hybrid slightly shifts towards the direction of low scattering angle, corroborating the expanded interlayer distance as revealed by the above TEM results. The diffraction signal for graphene is not visible due to the intense peaks from MoS2 crystals, so Raman measurement was applied. As can be seen from the inset of 2@G hybrid exhibits two sharp bands at 1360  and 1600 cm−1 , as well as two broad bands at 2690 (2D band) and 2920 cm−1 (D + G band),49 which directly proved the existence of well-crystallized few-layered graphene structure in the hybrid. The hexagonal layered structure of the MoS2 in the hybrid was further confirmed by Raman spectrum with two peaks located at 383 and 407 cm−1 . As shown in 407 cm−1 , which a72.2 wt% .2@G hybrid was quantified by Brunauer–Emmett–Teller (BET) method. Results from the full nitrogen adsorption and desorption isotherms  method, are mainly distributed in the region of mesopores to macropores with a peak centered at 3.87 nm , the first peak at 1.20 V can be ascribed to the intercalation of sodium ions into MoS2 interlayer , the peaks from 1.4 to 1.7 V should be attributed to the oxidation of Mo to MoS2.27 In the subsequent cycles, the peaks at 0.66/0.56 V shift to 1.04/0.75 V with decreased intensity, corresponding to the progressive amorphization of MoS2@G hybrid. Notably, the CVs rapidly become overlapped in the later cycles, suggesting high reversibility for the electrode material. The stability of sodiation/desodiation processes was also confirmed by comparing the cycling performances of MoS2@G hybrid and MoS2 under the galvanostatic mode at a current density of 0.1 A g−1, as shown in 2@G hybrid delivered a capacity as high as 484 mA h g−1 at the 2nd cycle and 474 mA h g−1 at the 100th cycle . In contrast, the MoS2 electrode delivered only a capacity of 268 mA h g−1 at the 2nd cycle and 97 mA h g−1 at the 50th cycle. Furthermore, the CE of the MoS2@G hybrid (>99%) is constantly higher than that of MoS2.The above structural characterizations of our MoS2@G hybrid at 0.05 A g−1 in the potential window of 0.01–3 V vs. Na+/Na. The distinct discharge/charge plateaus in the first cycle are ascribed to the sample's high crystallinity.23 The discharge and charge capacities for the first cycle are 750 and 630 mA h g−1, respectively, corresponding to a CE of 83.7% , the electrode material can still retain ∼67% of its capacity (from 530 to 357 mA h g−1). Moreover, the MoS2@G hybrid is able to recover most of its original capacity when the current rate is restored back to 0.05 A g−1 after forty deep cycles, indicating the high stability of the MoS2@G anode even upon high rate cycling . It is worth noting that, during these repeated discharge/charge cycles, the volume change induced pulverization of the MoS2@G hybrid electrode has been significantly suppressed, as reflected by the constantly high CE (>99%) throughout the measurement and the comparative postmortem TEM study. As shown in 2@G hybrid indicates the existence of small MoS2 flakes firmly decorated on graphene sheets. The MoS2 content remains highly crystallized except the irregular outlines after such long cycling. Moreover, the uniform distribution of MoS2 on graphene sheets was also successful maintained. In contrast, the MoS2 sample shows considerable cracks across the flakes throughout the cycling . We believe that the unique microstructural features of the MoS2@G hybrid itself have brought multiple advantages to act as high-performance electrode materials. First, the thin MoS2 nanoflakes (5–10 nm in thickness) with expanded interlayer spacing (0.65 nm) greatly reduces the strain caused by insertion and extraction of Na+. Second, the high surface area of the MoS2@G hybrid (196.93 m2 g−1) provides a large electrode–electrolyte interface, in facilitating the critical charge-transfer process. Third, the monolithic graphene ensures a 3D porous and flexible scaffold to protect MoS2 from dissolution or detachment during repeated cycles, as well as 3D interconnected pathways for electron transport and Na-ion diffusion. Finally, the homogeneous distribution of MoS2 nanoflakes on graphene nanosheets together with their intimate contact guarantees good conductivity (for both Na+ and electrons), and hence a high level of electrochemical activity and effective material utilization of the MoS2 2MoS4 and glucose (weight ratio of 1 : 1.5) was directly subjected to thermal treatment in a horizontal furnace. As shown in The MoSα radiation . Raman measurement was taken using a Horiba Jobin Yvon LabRAM HR system with a laser wavelength of 488 nm. The nitrogen adsorption and desorption isotherms were obtained at 77 K with a Micromeritics ASAP 2020 volumetric adsorption analyzer.The samples were characterized by different analytical techniques. Simultaneous TG/DSC analysis was performed on a NETZSCH STA 449 C Jupiter system. Optical image was captured on a Nikon Microphot-FXA microscope. SEM observations were made on a JEOL JSM-6700F field-emission SEM. TEM images, SAED pattern, EELS, and EDS were obtained on a JEOL JEM-2100F STEM  system equipped with an Oxford INCA x-sight EDS and an ENFINA 1000 EELS. XPS spectra were acquired on a Thermo Scientific Escalab 250Xi spectrometer. XRD measurement was conducted using a Rigaku SmartLab Intelligent X-ray diffraction system with filtered Cu K4 in the mixed solvent of ethylene carbonate/dimethyl carbonate (1 : 1 v/v ratio) with 5 wt% fluoroethylene carbonate as additive was selected as the electrolyte for the coin cells. CV measurement was conducted on an electrochemical measurement system (PARSTAT 2273) with a scan rate of 0.2 mV s−1 from 3 to 0.01 V. Galvanostatic charge/discharge tests were performed by using a battery testing system (LAND CT2001A) within the potential of 0.01–3 V at room temperature. The capacities are given with respect to the total mass of the active materials throughout the work.The working electrode slurry was prepared by mixing the active materials with Super P and carboxymethyl cellulose binder at a mass ratio of 8 : 1 : 1. The slurry was then spread on the surface of a copper foil and dried at 60 °C for 12 h. Finally, the electrode was stamped into disks with a diameter of 10 mm and vacuum-dried at 60 °C for another 6 h. With sodium tablets as the reference electrode and glass fiber membrane as the separator, CR2032 coin cells were assembled in a glove box  filled with argon. 1 M NaClOL. F., C. L. M., and Y. W. conceived the idea and designed the experiment. L. F. and J. J. prepared samples. L. F., J. J., S. M. N., L.-L. S., L. S., and K. X. conducted structural characterizations. L. F. and M. X. performed electrochemical measurements. H. H. and C. W. L. contributed to critical discussions. L. F., C. L. M., and Y. W. wrote the manuscript, and all authors commented on it. Y. W. and C. L. M. supervised implementation of project. All authors have given approval to the final version of the manuscript. L. F. and M. X. contributed equally to this work.There are no conflicts to declare.RA-008-C7RA12617D-s001


Sarcoidosis has been and remains a challenge for patients and physicians alike. Even in the year 2022, the pathophysiology of sarcoidosis is still incompletely understood. With this Research Topic entitled “Sarcoidosis—The Great Mimicker,” we aimed to shed light on the various aspects of this enigmatic disease. We are thankful and indebted to all authors, reviewers, and external editors who have contributed with their research papers and time to make this a thriving collection of articles. We received many submissions indicating that sarcoidosis attracts researchers from various backgrounds and specialties. With this editorial, we will give an overview of the topics covered in the Research Topic and place them in the context of the current research landscape.Tirelli et al. describes a case of concurrent adenocarcinoma of the lung and coexistent sarcoidosis, which is rare and therapeutically challenging. A recent systematic review identified nine case reports and highlighted that meticulous diagnostic testing is essential to differentiate metastatic disease from sarcoid or sarcoid-like lesions (The search terms (Sarcoidosis[Title]) AND (Case Reports[Filter]) in the commonly used database Pubmed retrieved a steadily increasing number of cases over the years and a total number of 7.280 reports. Starting in 1955, only one case was reported, which increased to 276 as of 2021 . Thus, cDe Cinque et al. focuses on testicular sarcoidosis, an exceedingly rare manifestation of sarcoidosis. They reviewed the literature and identified, including their case, only 20 publications where testicular sarcoidosis was the primary manifestation of sarcoidosis. Most interestingly, they described contrast-enhanced ultrasound (CEUS) features, which can be helpful in discerning sarcoidosis from other malignant testicular lesions. Specifically, sarcoid lesions are hypoechoic and show hypo-enhancement on CEUS, a clinically relevant point.The following case report by Manansala et al. describe a case series of COVID-19 in sarcoidosis patients of African American ethnicity. They report on five cases; one ultimately expired due to a thromboembolic event. This report, published relatively early in the pandemic, was reassuring for patients with sarcoidosis, especially African American patients, who usually suffer more from sarcoidosis than other ethnicities -17 and−12/23-antagonists or B-cell modulating agents, were negative. Clinical trials for anti-IL-6, anti-IL-1, and Janus kinase inhibitors are ongoing and have not been published yet. In light of the recently published American Thoracic Society/European Respiratory Society recommendations for the treatment of sarcoidosis, which confirmed the lack of robust evidence derived from high-quality clinical trials, these trial results are eagerly awaited  and infrequent (neurosarcoidosis) manifestations. In addition, they highlight diseases and conditions that treating physicians always need to be aware of, such as drug-induced sarcoid reactions, common-variable immunodeficiency with granulomas, and differential diagnoses for hypercalcemic syndromes.Adding to the review papers on dedicated topics concerning sarcoidosis is the article by Chioma et al. described the role of the lung microbiome in interstitial lung diseases (ILD), including sarcoidosis. Among the few dedicated studies available, the evidence for alterations in the gut or lung microbiome is mixed. In sarcoidosis specifically, alterations of the microbiome in the lungs have not been firmly established.The last review of the topic by Cacciatore et al. analyzed a French cohort regarding acute vs. chronic sarcoid arthropathy. In short, chronic arthropathy tended to be less symmetric, had more wrist involvement, and more often required second- or third-line therapies.A total of four original papers were included in the topic. The first paper by Cameli et al. identified serum and urinary calcium levels as a useful biomarker in sarcoidosis. The investigators compared sarcoidosis patients with idiopathic pulmonary fibrosis and hypersensitivity pneumonitis. Further, receiver operating characteristics curve analysis revealed an excellent specificity (89.7%) of hypercalciuria for sarcoidosis vs. non-sarcoidosis ILD and a specificity of 82.5% for fibrotic sarcoidosis vs. non-sarcoidosis ILD. This paper highlights the importance of calcium and vitamin D dysregulation in sarcoidosis, which is an area deserving of further investigation.The subsequent exciting investigation by Nickles et al. analyzed similarities between discoid lupus erythematosus (DLE), cutaneous sarcoidosis (CS), and psoriasis by gene co-expression networks. These complex analyses revealed seven common hub genes in DLE and CS: TLR1, ITGAL, TNFRSF1B, CD86, SPI1, BTK, and IL10RA. Furthermore, these analyses also identified several disease-type specific hub genes. These results identified potential molecular targets for treating skin lesions of these diseases.The following paper by Vagts et al. used unsupervised clustering in a cohort of sarcoidosis patients who had undergone a positron emission tomography (PET) scan as part of their workup. A detailed analysis of clinical, laboratory, and imaging features revealed three clusters . In addition, the data showed a reduction in lymphocyte counts in cluster 3 and high PET avidity in clusters 2 and 3.Lastly, These results are relevant since the current recommendations for the diagnosis and detection of sarcoidosis  still veSarcoidosis remains an enigmatic and complicated disease. Within this Research Topic, experts in the field have shared their insights, experience, and research data to deepen our understanding of sarcoidosis. In our view, the agenda for future research includes but is not limited to: (1) what does assist us in making a confident diagnosis of sarcoidosis?, (2) the development of disease clustering criteria for clinical trials, (3) a definition of an applicable response index for measuring outcomes in clinical trials, (4) further explore the role of calcium/vitamin D metabolism in sarcoidosis, and (5) investigate the molecular mechanisms underlying the pathogenesis of the disease. Specialists from all fields, such as pulmonologists, rheumatologists, dermatologists, and neurologists, among many others, should embrace these challenges to improve the diagnosis and treatment of sarcoidosis patients for whom very few therapeutic options are available.PK conceived the article, wrote the manuscript, and created the figure. NS and MM reviewed and edited the paper. All authors contributed to the article and approved the submitted version.Author PK has received honoraria or travel support from Abbvie, Amgen, AstraZeneca, Boehringer Ingelheim, Bristol-Myers-Squibb, Chugai, Galapagos Biopharma, GlaxoSmithKline, Janssen-Cilag, Lilly, Pfizer, and Sanofi-Aventis, all unrelated to this paper. Author PK received research grants from GlaxoSmithKline and Diamed Medizintechnik GmbH, all unrelated to this paper. Author MM reports research awards from Mallinckrodt, advisory membership in Mallinckrodt. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.