This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. HIGHLIGHTS Methods of guiding students to effectively and appropriately regulate their emotions during public health emergencies and avoid losses caused by crisis events have become an urgent problem for colleges and universities. Therefore, we investigated and analyzed the mental health status of college students during the epidemic for the following purposes.(1) To evaluate the mental situation of college students during the epidemic;(2) to provide a theoretical basis for psychological interventions with college students; and (3) to provide a basis for the promulgation of national and governmental policies. AbstractA COVID-19 epidemic has been spreading in China and other parts of the world since December 2019. The epidemic has brought not only the risk of death from infection but also unbearable psychological pressure. We sampled college students from Changzhi medical college by using cluster sampling. They responded to a questionnaire packet that included the 7-item Generalized Anxiety Disorder Scale (GAD-7) and those inquiring the participants' basic information. We received 7,143 responses. Results indicated that 0.9% of the respondents were experiencing severe anxiety, 2.7% moderate anxiety, and 21.3% mild anxiety. Moreover, living in urban areas (OR = .810, 95% CI = .709 -.925), family income stability (OR = .726, 95% CI = .645 -.817) and living with parents (OR = .752, 95% CI = .596 -.950) were protective factors against anxiety. Moreover, having relatives or acquaintances infected with COVID-19 was a risk factor for increasing the anxiety of college students (OR = 3.007, 95% CI = 2.377 -3.804). Results of correlation analysis indicated that economic effects, and effects on daily life, as well as delays in academic activities, were positively associated with anxiety symptoms (P < .001). However, social support was negatively correlated with the level of anxiety (P < .001). It is suggested that the mental health of college students should be monitored during epidemics.

Wave effects of phonons can give rise to controllability of heat conduction beyond that by particle scattering at surfaces and interfaces. In this work, we propose a new class of 3D nanostructure: a silicon-nanowire-cage (SiNWC) structure consisting of silicon nanowires (SiNWs) connected by nano-cross-junctions (NCJs). We perform equilibrium molecular dynamics (MD) simulations, and find an ultralow value of thermal conductivity of SiNWC, 0.173 Wm -1 K -1 , which is one order lower than that of SiNWs.By further modal analysis and atomistic Green's function calculations, we identify that the large reduction is due to significant phonon localization induced by the phonon local resonance and hybridization at the junction part in a wide range of phonon modes. This localization effect does not require the cage to be periodic, unlike the phononic crystals, and can be realized in structures that are easier to synthesize, for instance in a form of randomly oriented SiNWs network.KEYWORDS: Nano-cross-junction, silicon-nanowires-cage, thermal conductivity, local phonon resonance, random network of silicon nanowiresOver the past decades, nanostructures have attracted great attentions due to its unique properties, including the low thermal conductivity. Most-commonly exercised approach is to lower thermal conductivity by phonon scattering at boundaries (surfaces and interfaces) that becomes dominant over intrinsic scattering as the length scales of the nanostructures decreases. Taking silicon nanowires (SiNWs) as a representative material, reduction of thermal conductivity has been realized by enhanced phonon scatterings at surfaces or boundaries due to high surface-to-volume ratio. Another line of effort to further reduce thermal conductivity which works on bulk materials is to utilize wave nature of phonons. Periodic phononic crystals can terminate or inhibit phonon propagation by inducing interference of phonons reflected at boundaries [12][13][14][15]. A challenge here is to ensure the occurrence of wave interferences, which requires strict periodicity of the internal structure with a size on the order of the phonon waves, which is about 1 nm at room temperature. [16] In addition, boundaries of the internal structures need to be smooth enough to specularly reflect phonons. These make production of the phononic crystals by bottom-up synthesis and top-down fabrication extremely challenging. [17] Therefore, there is a strong need for a structure that can give rise to wave effects (interference, localization, and resonance) "locally" so that the periodicity is no longer and planar nanowire cross-junction architectures.[26] These works have shown the advantages of two-dimensional cross-junction over "bridge" junction.In this letter, based on the above bottom-up approach and planar nano-cross-junctions (NCJs), [26] we take a step further and propose a silicon-nanowire-cage (SiNWC) ( Fig. 1(c)) structure consisting of SiNWs ( Fig. 1(a)) and 3D-NCJs ( Fig. 1(b)). Thus, the 1DSiNW is turned into a 3D bulk material as show...

An effective strategy is proposed to enhance the oxygen reduction reaction (ORR) performance of multiwall carbon nanotubes (MWCNTs) in both acid and alkaline electrolytes by coating them with a layer of biomass derivative N‐doped hydrothermal carbons. The N‐doped amorphous carbon coating plays triple roles: it (i) promotes the assembly of MWCNTs into a 3D network therefore improving the mass transfer and thus increasing the catalytic activity; (ii) protects the Fe‐containing active sites, present on the surface of the MWCNTs, from H2O2 poisoning; (iii) creates nitrogenated active sites and hence further enhances ORR activity and robustness.

Objective: Coronavirus disease 2019 is an escalating global epidemic caused by SARS-CoV-2, with a high mortality in critical patients. Effective indicators for predicting disease severity in SARS-CoV-2 infected patients are urgently needed. Methods: In this study, 43 COVID-19 patients admitted in ChongqingPublic Health Medical Center were involved. Demographic data, clinical features, and laboratory examinations were obtained through electronic medical records. Peripheral blood specimens were collected from COVID-19 patients and examined for lymphocyte subsets and cytokine profiles by flow cytometry. Potential contributing factors for prediction of disease severity were further analyzed.Results: A total of 43 COVID-19 patients were included in this study, including 29 mild patients and 14 sever patients. Severe patients were significantly older (61.9±9.4 vs 44.4±15.9) and had higher incidence in co-infection with bacteria compared to mild group (85.7%vs27.6%).Significantly more severe patients had the clinical symptoms of anhelation (78.6%) and asthma (71.4%). For laboratory examination, 57.1% severe cases showed significant reduction in lymphocyte count.The levels of Interluekin-6 (IL6), IL10, erythrocyte sedimentation rate (ESR) and D-Dimer (D-D) were significantly higher in severe patients than mild patients, while the level of albumin (ALB) was remarkably : medRxiv preprint lower in severe patients. Further analysis demonstrated that ESR, D-D, age, ALB and IL6 were the major contributing factors for distinguishing severe patients from mild patients. Moreover, ESR was identified as the most powerful factor to predict disease progression of COVID-19 patients. Conclusion:Age and the levels of ESR, D-D, ALB and IL6 are closely related to the disease severity of COVID-19 patients. ESR can be used as a valuable indicator for distinguishing severe COVID-19 patients in early stage, so as to increase the survival of severe patients.

Hydrophilic acrylamide-based hydrogels are emerging platforms for numerous applications, but our ability to fully exploit these materials is currently limited. A deepening of our understanding of molecular-level structure/property relationships in hydrogels is crucial to progressing these efforts. Such relationships can be challenging to elucidate on the basis of experimental data alone. Here, we use molecular simulations as a complementary strategy to reveal the molecular-level phenomena that govern the thermo-mechanical properties of hydrogels. We focus on acrylamide-based hydrogels cross-linked with N,N'methylenebisacrylamide, generated using our previously-established computational crosslinking procedure. We find the water content to be a key determinant in the elastic response of these hydrogels, with enhanced tensile and shear properties at low water content. However, we also find increasing water content enhances the hydrogel's thermal conductivity, with the dominant contribution arising from the non-bonded contributions to the heat flux. In addition, chemical cross-linking improved the heat transfer properties of the hydrogel, whereas a reduction in convective heat transfer was predicted with an increase in hydrogel crosslinking. Our simulations provide a rational basis for designing and testing customized hydrogel formulations for maximising both thermal conductivity and mechanical properties.