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The production of nitrogen-doped carbon quantum dots (N-CDs) from walnut shell waste is crucially important for green chemistry and sustainable development. Herein we fabricate N-CDs by a bottom-up solvothermal method and use the novel N-CDs to modify the electron transport layer (ETL) in perovskite solar cells (PVSCs). The N-CDs can produce 440 nm fluorescence under the excitation of 350 nm light with a quantum yield of 8.75%. Infrared absorption spectra show that N-CDs contain high proportions of nitrogen-containing and oxygen-containing functional groups. , Through the incorporation of N-CDs into SnO2 ETL, the formation of defects is inhibited, and crystallinity is improved. This is because the N-CDs contains a large number of functional groups such as nitrogen and oxygen and these groups would interact with the ETL and perovskite, which reduce the defect/trap centers in PVSCs. Therefore, the N-CDs modified PVSCs show improved power conversion efficiency. This study provides a novel way to use walnut shell waste to synthesize N-CDs and achieve efficient and stable perovskites solar cells.

Purpose This study aimed to investigate the comparison and relationship between serum heat shock protein 72 (sHSP72) and intestinal permeability in patients with cerebral infarction (CI) and healthy individuals to elucidate the link to gut microbiota alterations and clinical severity of CI. Methods Stool samples of 50 CI patients and 46 healthy volunteers were applied to characterize intestinal flora profile through 16S rRNA gene sequencing. Composition difference and taxon evaluation were observed. sHSP72 and zonulin were assayed using enzyme-linked immunoassay (ELISA). Medical comorbidities and dietary habits were acquired using questionnaires and partial biochemical index were recorded. The obtained data were then subjected to comparative and correlative analysis. Results We found that the levels of zonulin and sHSP72 were significantly higher in CI group compared to the healthy group. Strikingly, sHSP72 and zonulin levels were positively correlated in CI group. After adjustment for age, gender, medical comorbidities and biochemical index, sHSP72 and zonulin levels correlated positively with clinical severity of CI. In the CI patient group, the abundance of bacteria Eubacterium_fissicatena_group, Eubacterium_eligens_group and Romboutsia manifested remarkably positive correlation with sHSP72. The abundance of bacteria Eubacterium_fissicatena_group and Acetivibrio were significantly positive correlation with zonulin levels. The CI group had a decreased abundance of Eubacterium_fissicatena_group, Eubacterium_eligens_group and Romboutsia, and an increased abundance of Acetivibrio. Conclusion Our findings represented that an increase in sHSP72 and zonulin levels were manifested in patients with CI and related to specific gut microbiota alterations and the clinical severity of CI.

Aims The aims of this study were to assess how functional diversity (FD) and functional redundancy respond to subalpine meadow ecosystem degradation under anthropogenic disturbance and how species contribute to functional redundancy along the disturbance gradient. Methods The study was carried out in the subalpine meadow in Mount Jade Dragon, which is located at the southeastern edge of the Tibetan Plateau. Four disturbance intensities [no disturbance (ND), weak disturbance (WD), moderate disturbance (MD) and severe disturbance (SD)] were identified. Species richness, soil properties and five key plant functional traits were assessed along the disturbance gradient. Simpson’s diversity index, FD based on the Rao algorithm, functional redundancy, community-weighted mean of each functional trait and species-level functional redundancy were determined. Important Findings Unimodal change pattern of FD and functional redundancy along the disturbance gradient were found in the present study, with their maximum in MD and WD, respectively. Species diversity showed a decreasing trend with increasing disturbance intensity. As disturbance intensified, species with traits related to conservative growth strategies, such as low specific leaf area (SLA) and high leaf dry matter content (LDMC), decreased, whereas species with resource acquisitive strategies, such as small plant, high SLA and low LDMC, increased in the community. At the species level, species showed species-specific roles in functional redundancy. Notably, some species were important in the community in terms of their unique function. For instance, Ligularia dictyoneura in ND and Potentilla delavayi in MD and SD.

The shuttle effect and sluggish conversion kinetics of lithium polysulfides (LiPSs) restrict the practical application of lithium–sulfur (Li–S) batteries. Herein, we introduce nickel cobaltite/carbon nanofiber (NiCo₂O₄/CNF) composites as a chemical trapper and conversion accelerator for LiPSs. The experiment and density functional theory indicate that polar NiCo₂O₄ can strongly trap polysulfides through Ni–S and Co–S bonds. The CNF network provides structural stability and serves as a second barrier for polysulfides. Systematic studies on the solid₍ₛᵤₗfᵤᵣ₎–liquid₍ₚₒₗyₛᵤₗfᵢdₑₛ₎–solid₍ₛᵤₗfᵢdₑ₎ conversion reactions qualitatively and quantitatively demonstrate that the well-designed NiCo₂O₄/CNF interface with strong polysulfides affinity, affluent polar nucleation sites, and fast Li⁺/e– transport can noteworthily catalyze the liquid-phase conversion of LiPSs and the solid-phase deposition of lithium sulfide (Li₂S) and protect the lithium anode as well. Thus, the NiCo₂O₄/CNF-based batteries can exhibit a high rate capability of 870 mAh g–¹ at 5 C and excellent cycling performance evidenced by a capacity retention of 95% after 200 cycles at 0.1 C with a sulfur loading of 6.3 mg cm–². Further increasing the sulfur loading to 7.9 mg cm–² and with a lean electrolyte/sulfur (E/S) ratio of 7.2 μL mgₛ–¹, the Li–S battery can deliver a high areal capacity of 8.1 mAh cm–².

Long-term arsenic exposure is a worldwide public health problem that causes serious harm to human health. The liver is the main target organ of arsenic toxicity; arsenic induces disruption of the DNA damage repair pathway, but its mechanisms remain unclear. In recent years, studies have found that epigenetic mechanisms play an important role in arsenic-induced lesions. In this study, we conducted experiments in vitro using normal human liver cells (L-02) to explore the mechanism by which the histone demethylase JHDM2A regulates H3K9 dimethylation (me2) in response to arsenic-induced DNA damage. Our results indicated that arsenic exposure upregulated the expression of JHDM2A, downregulated global H3K9me2 modification levels, increased the H3K9me2 levels at the promoters of base excision repair (BER) genes (N-methylpurine-DNA glycosylase [MPG], XRCC1 and poly(ADP-ribose)polymerase 1) and inhibited their expression levels, causing DNA damage in cells. In addition, we studied the effects of overexpression and inhibition of JHDM2A and found that JHDM2A can participate in the molecular mechanism of arsenic-induced DNA damage via the BER pathway, which may not be involved in the BER process because H3K9me2 levels at the promoter region of the BER genes were unchanged following JHDM2A interference. These results suggest a potential mechanism by which JHDM2A can regulate the MPG and XRCC1 genes in the process of responding to DNA damage induced by arsenic exposure and can participate in the process of DNA damage repair, which provides a scientific basis for understanding the epigenetic mechanisms and treatments for endemic arsenic poisoning.

The application and accumulation of phosphogypsum (PG) may cause soil pollution, so it is of significance to establish a rapid method for its determination in soil. In this study, the feasibility of quantifying PG in soil by multivariate calibration combined with portable near-infrared spectroscopy (NIR) and infrared spectroscopy (IR) was investigated. In order to obtain better accuracy, standard normal variable (SNV) and Savitzky-Golay smoothing were employed as the pretreatment methods for IR and NIR, respectively. The competitive adaptive reweighted sampling (CARS) algorithm was used for variable optimization of these models. The results show that the predictive determination coefficient and root mean square error of prediction (RMSEP) of IR and NIR partial least squares (PLS) models were 0.9933 and 1.88% and 0.8830 and 6.55%. The limits of detection (LOD) for the models were 4.0006% and 14.225%. The reproducibility of the models is satisfactory with good accuracy and precision. In addition, extreme learning machine (ELM) and support vector machine (SVM) algorithms were also used to analyze the data, resulting in similar outcomes to those obtained by PLS. The results of a dual t test demonstrated that there is no significant difference between these methods and the standard procedure (GB/T 23456-2018) at the 95% confidence level. However, the reported protocols have the advantages of on-site analysis, speed, and convenience for the determination of phosphogypsum in soil.

Digitalization and low-carbon development are parallel in the digital economy. In what ways does the development of low-carbon economy can be contributed by the digital transformation of enterprises? This paper analyzes the impact of digital transformation on carbon emissions from a micro perspective. Based on unbalanced panel data from 278 listed companies between 2010 and 2018, a double fixed-effect model is used to test the overall effects of digitalization on carbon emission intensity, the intermediary role of green technology innovation capacity and the regulatory effect of absorptive capacity. Results show that digital transformation of enterprises contributes to the reduction of carbon emission intensity, green technology innovation capability partially mediates the impact of digital transformation on carbon emission intensity, and absorptive capacity moderates the impact of digital transformation on green technology innovation capacity. Based above, this paper puts forward corresponding countermeasures from the aspects of digitalization, greening and low carbon.

The Jinchang Cohort was an ongoing 20-year ambispective cohort with unique metal exposures of an occupational population. Until now, the Jinchang Cohort has completed three phases of follow-up from January 2014 to December 2019. The baseline cohort was completed from June 2011 to December 2013, and a total of 48 001 people were included. Three phases of follow-ups included 46 713, 41 888 and 40 530 participants, respectively. The death data was collected from 2001 to 2020. The epidemiological, physical examination, physiological and biochemical data of the cohort were collected by using the methods of cross-section and prospective cohort study. Biological specimens were collected on baseline to establish a biological specimen bank. The concentrations of metals in urine and serum were detected by inductively coupled plasma mass spectrometry (ICP-MS). The new areas of research aim to study the all-cases mortality, the burden of diseases, heavy metals and diseases, and course of the chain from disease to high-risk outcomes using a combination of macro and micro means, which provided scientific basic to explore pathogenesis of multi-etiology and multi-disease, and to evaluate the effects of the intervention measures in the population.

The Jinchang Cohort was an ongoing 20-year ambispective cohort with unique metal exposures to an occupational population. From January 2014 to December 2019, the Jinchang Cohort has completed three phases of follow-up. The baseline cohort was completed from June 2011 to December 2013, and a total of 48 001 people were included. Three phases of follow-ups included 46 713, 41 888, and 40 530 participants, respectively. The death data were collected from 2001 to 2020. The epidemiological, physical examination, physiological, and biochemical data of the cohort were collected at baseline and during follow-up. Biological specimens were collected on the baseline to establish a biological specimen bank. The concentrations of metals in urine and serum were detected by inductively coupled plasma mass spectrometry (ICP-MS). The new areas of research aim to study the all-cases mortality, the burden of diseases, heavy metals and diseases, and the course of the chain from disease to high-risk outcomes using a combination of macro and micro means, which provided a scientific basis to explore the pathogenesis of multi-etiology and multi-disease and to evaluate the effects of the intervention measures in the population.

Formyl peptide receptors (FPRs) are a group of G protein-coupled cell surface receptors that play important roles in host defense and inflammation. Owing to the ubiquitous expression of FPRs throughout different cell types and since they interact with structurally diverse chemotactic agonists, they have a dual function in inflammatory processes, depending on binding with different ligands so that accelerate or inhibit key intracellular kinase-based regulatory pathways. Neuroinflammation is closely associated with the pathogenesis of neurodegenerative diseases, neurogenic tumors and cerebrovascular diseases. From recent studies, it is clear that FPRs are important biomarkers for neurological diseases as they regulate inflammatory responses by monitoring glial activation, accelerating neural differentiation, regulating angiogenesis, and controlling blood brain barrier (BBB) permeability, thereby affecting neurological disease progression. Given the complex mechanisms of neurological diseases and the difficulty of healing, we are eager to find new and effective therapeutic targets. Here, we review recent research about various mechanisms of the effects generated after FPR binding to different ligands, role of FPRs in neuroinflammation as well as the development and prognosis of neurological diseases. We summarize that the FPR family has dual inflammatory functional properties in central nervous system. Emphasizing that FPR2 acts as a key molecule that mediates the active resolution of inflammation, which binds with corresponding receptors to reduce the expression and activation of pro-inflammatory composition, govern the transport of immune cells to inflammatory tissues, and restore the integrity of the BBB. Concurrently, FPR1 is essentially related to angiogenesis, cell proliferation and neurogenesis. Thus, treatment with FPRs-modulation may be effective for neurological diseases.

The crystal morphology and geometry may play a role in electronic dissemination transition, and they would lay the foundation for the assembly about various accessories. The main aim of our research is to investigate a variety of factors which had an impact on the types and morphologies of the final products during the Co(OH)2 crystal formation process, such as substrate material, reaction concentration and reaction time. In this paper, Co(OH)2 microspheres are successfully prepared by a facile hydrothermal synthesis method, using cobalt nitrate hexahydrate and ammonium fluoride as the raw material, ammonia as the complexing agent and a clean nickel or copper foam as the base material. The structure and morphology of samples are characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM).

Objective: Both exposure to heavy metals and alcohol intake have been related to the risk of type 2 diabetes (T2D). In this study, we aimed to assess the potential interactions between metal exposure and alcohol intake on the risk of T2D and prediabetes in a cohort of Chinese male workers. Methods: We conducted a cross-sectional analysis of 26,008 Chinese male workers in an occupational cohort study from 2011 to 2013. We assessed metal exposure and alcohol consumption at baseline in these workers who were aged ≥20 years. Based on occupations which were categorized according to measured urine metal levels, multiple logistic regression analyses were used to evaluate the independent and joint effects of metal and alcohol exposure on the risk of T2D and prediabetes. Results: Risks of T2D (Ptrend = 0.001) and prediabetes (Ptrend = 0.001) were significantly elevated with increasing number of standard drinks per week, years of drinking, and lifetime alcohol consumption. An adjusted odds ratio (OR) of 6.1 (95% confidence interval [CI]: 4.8–7.8) was observed for the smelting/refining workers (highest metal exposure levels) who had the highest lifetime alcohol consumption (>873 kg) (Pinteraction = 0.018), whereas no statistically significant joint effect was found for prediabetes (Pinteraction = 0.515). Conclusions: Both exposures to metal and heavy alcohol intake were associated with the risk of diabetes in this large cohort of male workers. There was a strong interaction between these two exposures in affecting diabetes risk that needs to be confirmed in future studies. Keywords: Metals, Alcohol, Type 2 diabetes, Prediabetes, Interaction

Based on measurements over a period of more than 650 days, we investigated the long-term stability of superconducting Mo–Cu bilayer films in the laboratory environment. The samples are based on sputtered films, which were grown for fabricating transition-edge sensor (TES) arrays. The results show an increasing trend of their superconducting transition temperature ( T c ) and transition width with time. There appears to be a turning point between 150 and 200 d, after which the rate of increasing becomes smaller. We suspect that oxidation occurred at the interface of the bilayer, through exposed edges, until the edges are fully oxidized. If proven, the slower rising trend would reflect the subsequent evolution of the bilayer films through, e.g. further oxidation of the interface, which might change T c through the proximity effect. We quantified the proximity effect with our bilayer samples of different Cu-to-Mo thickness ratios. As a function of the thickness ratio, the measured T c values are fitted well with the Martinis equation, provided that the transmission coefficient (between the layers) and T c , M o of the Mo layer are both allowed to vary. Based on the best-fit model, we found that a change of about 1% in the transmission coefficient would be sufficient to account for the slower variation in the bilayer transition temperature. We also noticed that the best-fit value of T c , M o is significantly higher than that measured for our bare Mo films. This could also be explained by surface oxidation of the Mo film samples. The implications of our results on TES-related applications are discussed.

To address the problems of poor generalization performance, high computational cost and low prediction accuracy of existing methods for evaluation of college students' mental health, we propose a mental health evaluation method based on WLLE (weighted locally linear embedding) and MLP (multilayer perceptron). First of all, by using the cluster sampling method, with SCL90 as the test scale, the mental health data of college students was collected using paper questionnaires and online questionnaires, and the data was pre-processed. Then, the WLLE algorithm is employed for dimensionality reduction of high-dimensional data, and the key features of dataset are extracted. Finally, the nonlinear classifier MLP is used to classify the extracted feature data, and the mental health states of samples to be tested are evaluated. The experimental results prove that compared to the existing mental health early warning methods, the method proposed in this paper can provide higher prediction precision and stronger generalization performance.

The Hot Universe Baryon Surveyor (HUBS) is a satellite concept proposed in China to address the so-called “missing baryon problem”, which has serious implications on the formation and evolution of galaxies. At the heart of HUBS there is a high-resolution soft X Ray spectrometer based on transition-edge sensors operating below 100 mK. A cooling system is needed to provide such a low-temperature environment. It necessarily consists of a precooling stage and a cold stage. The cold stage could be enabled by an adiabatic demagnetization refrigerator (ADR). Because an ADR could be operated without gravity’s assist and has no refrigerant consumption, it is a good candidate for satellite mission like HUBS. For HUBS, the ADR will be employed to cool the detector down to below 100 mK from the precooling stage (at about 4K), which is enabled by mechanical pulse tube refrigerators. ADR for HUBS is now under development in our lab. The key technologies of building an ADR including growth of paramagnetic salt pill crystals, gas-gap heat switch are under development. A preliminary design of the ADR is completed and the design parameters are optimized. In this paper, we report on the status of the development.

The Hot Universe Baryon Surveyor (HUBS) is a satellite mission that is proposed to probe “hidden” baryons in the universe and thus to fill a void in observational astronomy that seriously affects our understand of galaxy formation and evolution. The HUBS payload is highly optimized for detecting diffuse X-ray emission from the baryons, with the combination of large field of view and high spectral resolution. To assess the scientific capabilities of HUBS, we created mock observations with data from a state-of-the-art cosmological hydrodynamical simulation (IllustrisTNG). The targets include systems that are representative of galaxies, galaxy groups, and galaxy clusters at various redshifts. We generated the X-ray spectra and images of the selected sources from the mock observations, taking into account galactic foreground emission, X-ray emission from cosmologically distant background sources, as well as emission from other sources along the lines of sight. The results from analyzing the mock observations show that the assumed design of HUBS is appropriate for achieving its primary scientific objectives. In this paper, we present the results and discuss issues related to observing strategies.

Hot Universe Baryon Surveyor (HUBS)1 is being conceptualized in China as a high throughput and highresolution spectroscopic X-ray mission dedicated to studying cosmic “missing” baryons, which are thought to exist in the gas of very low density and temperature of roughly one million degrees in the halo of galaxies or in large-scale structures. To detect weak emission from the “missing” baryons, HUBS will employ an X-ray microcalorimeter based on transition-edge sensors (TES) array that operates at very low temperatures. The key characteristics of the detector technology are excellent energy resolution and high quantum efficiency, which makes it an ideal choice for constructing a non-dispersive X-ray imaging spectrometer. We are developing X-ray microcalorimeters for HUBS, based on superconducting Mo/Cu bilayer films. In this work, we present results on characterization of the Mo/Cu films and TES devices at temperatures below 200 mK, including their I − V characteristics, pulse signals and energy resolutions. We have also studied correlations between the superconductivity and other properties of the films (including residual resistivity ratio, stress, crystalline structure, interface properties, etc.). Preliminary results are presented in this work.

By extracting low-level features under the rectangular coordinate system, traditional leaf recognition methods typically have properties such as high dimensionality of extracted features, high-computational requirement and weak generalization performance. Based on the manifold learning algorithm D-LLE, we proposed a novel leaf recognition method under the polar coordinate system. The method first extracts from the leaf images high-dimensional features associated with polar coordinate as the preprocessing. Consequently, D-LLE is harnessed to reduce the features' dimensionality. In the low-dimensional space, we use the nearest neighbor classifier to make final determination. Experimental results exhibit higher effectiveness and efficiency of our method compared with classical traditional methods.

Background This case-control study is aimed to investigate the correlation of altered functional connectivity (FC) in cerebellum with cognitive impairment in amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD).Methods The morphometric and resting-state FC MRI analysis including 47 participants with AD, 32 with aMCI and 43 age-matched normal controls (NCs) were conducted. We compared the cerebellar gray matter volume and cerebellar FC with cerebral cortical regions among three groups. To investigate the relationship of cerebellar FC with cognition, we measure the correlation of significant altered FC and individual cognitive domain.Results No significant morphometric differences of cerebellum was observed across three groups. The patients with AD had weaker cerebral cortical FCs in bilateral Crus I, left VIIb and IX compared to NCs, and in bilateral Crus I compared to patients with aMCI. For patients with aMCI, the weaker FC were found between right Crus I, left VIIb and IX and cerebral cortical regions compared to NCs. The strength of left cerebellar FC positively correlated with specific cognitive subdomains, including executive function, attention, visuospatial function, and global cognition in AD and aMCI.Conclusions These findings demonstrated the alteration of cerebellar FC with cerebral cortical regions, and the correlation of cerebellar FC and cognitive impairment in AD and aMCI.

Background Cyanobacteria are of special concern because they proliferate in eutrophic water bodies worldwide and affect water quality. As an ancient photosynthetic microorganism, cyanobacteria can survive in ecologically diverse habitats because of their capacity to rapidly respond to environmental changes through a web of complex signaling networks, including using second messengers to regulate physiology or metabolism. A ubiquitous second messenger, bis-(3′,5′)-cyclic-dimeric-guanosine monophosphate (c-di-GMP), has been found to regulate essential behaviors in a few cyanobacteria but not Microcystis, which are the most dominant species in cyanobacterial blooms. In this study, comparative genomics analysis was performed to explore the genomic basis of c-di-GMP signaling in Microcystis aeruginosa. Results Proteins involved in c-di-GMP metabolism and regulation, such as diguanylate cyclases, phosphodiesterases, and PilZ-containing proteins, were encoded in M. aeruginosa genomes. However, the number of identified protein domains involved in c-di-GMP signaling was not proportional to the size of M. aeruginosa genomes (4.97 Mb in average). Pan-genome analysis showed that genes involved in c-di-GMP metabolism and regulation are conservative in M. aeruginosa strains. Phylogenetic analysis showed good congruence between the two types of phylogenetic trees based on 31 highly conserved protein-coding genes and sensor domain-coding genes. Propensity for gene loss analysis revealed that most of genes involved in c-di-GMP signaling are stable in M. aeruginosa strains. Moreover, bioinformatics and structure analysis of c-di-GMP signal-related GGDEF and EAL domains revealed that they all possess essential conserved amino acid residues that bind the substrate. In addition, it was also found that all selected M. aeruginosa genomes encode PilZ domain containing proteins. Conclusions Comparative genomics analysis of c-di-GMP metabolism and regulation in M. aeruginosa strains helped elucidating the genetic basis of c-di-GMP signaling pathways in M. aeruginosa. Knowledge of c-di-GMP metabolism and relevant signal regulatory processes in cyanobacteria can enhance our understanding of their adaptability to various environments and bloom-forming mechanism.