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Purpose: To investigate the correlation between socioeconomic status (SES) and the incidence of hypertension among adults aged 18 or above in southwest China. Methods: A multistage proportional stratified cluster sampling method was employed to recruited 9280 adult residents from 12 counties in southwest China, with all participants in the cohort tracked from 2016 to 2020. The questionnaire survey gathered information on demographics, lifestyle habits, and household income. The physical exam recorded height, weight, and blood pressure. Biochemical tests measured cholesterol levels. The chi-square test was employed to assess the statistical differences among categorical variables, while the Cox proportional hazards regression model was applied to evaluate the association between socioeconomic status (SES) and the incidence of hypertension. Results: The finally effective sample size for the cohort study was 3546 participants, after excluding 5734 people who met the exclusion criteria. Adults in the highest household income group had a significantly lower risk of hypertension compared to those in the lowest income group (HR = 0.636, 95% CI: 0.478–0.845). Besides, when compared to individuals in the illiterate population, the risk of hypertension among adults with elementary school, junior high school, senior high school and associate degree educational level decreased respectively by 34.4% (HR = 0.656, 95%CI: 0.533–0.807), 44.9% (HR = 0.551, 95%CI: 0.436–0.697), 44.9% (HR = 0.551, 95%CI: 0.405–0.750), 46.1% (HR = 0.539, 95%CI: 0. 340–0.854). After conducting a thorough analysis of socioeconomic status, compared with individuals with a score of 6 or less, the risk of hypertension in participants with scores of 8, 10, 11, 12, and greater than 12 decreased respectively by 23.9% (HR = 0.761, 95%CI: 0.598–0.969), 29.7% (HR = 0.703, 95%CI: 0.538–0.919), 34.0% (HR = 0.660, 95%CI: 0.492–0.885), 34.3% (HR = 0.657, 95%CI: 0.447–0.967), 43.9% (HR = 0.561, 95%CI: 0.409–0.769). Conclusion: The findings indicate a negative correlation between socioeconomic status and hypertension incidence among adults in southwest China, suggesting that individuals with higher socioeconomic status are less likely to develop hypertension. [ABSTRACT FROM AUTHOR]

Background: Curcubita ficifolia Bouché (Cucurbitaceae) has high value as a food crop and medicinal plant, and also has horticultural value as rootstock for other melon species. China is home to many different cultivars, but the genetic diversity of these resources and the evolutionary relationships among them, as well as the differences between C. ficifolia and other Cucurbita species, remain unclear. Results: We investigated the chloroplast (cp) genomes of 160 C. ficifolia individuals from 31 populations in Yunnan, a major C. ficifolia production area in China. We found that the cp genome of C. ficifolia is ~151 kb and contains 128 genes, of which 86 are protein coding genes, 34 encode tRNA, and eight encode rRNAs. We also identified 64 SSRs, mainly AT repeats. The cp genome was found to contain a total of 204 SNP and 57 indels, and a total of 21 haplotypes were found in the 160 study individuals. The reverse repeat (IR) region of C. ficifolia contained a few differences compared with this region in the six other Cucurbita species. Sequence difference analysis demonstrated that most of the variable regions were concentrated in the single copy (SC) region. Moreover, the sequences of the coding regions were found to be more similar among species than those of the non-coding regions. The phylogenies reconstructed from the cp genomes of 61 representative species of Cucurbitaceae reflected the currently accepted classification, in which C. ficifolia is sister to the other Cucurbita species, however, different interspecific relationships were found between Cucurbita species. Conclusions: These results will be valuable in the classification of C. ficifolia genetic resources and will contribute to our understanding of evolutionary relationships within the genus Cucurbita. [ABSTRACT FROM AUTHOR]

As a major component of water cycle, the accuracy quantification of different precipitation products is critical for evaluating climate change and ecosystem functions. However, a lack of evidence is available to choose a precise precipitation product in relative applications. Here, to solve this limit, we analyze the spatiotemporal pattern and accuracy of four precipitation products, including CHIRPS V2.0, PERSIANN-CDR, ECMWF ERA5-Land, and GLDAS_NOAH025_3H, over China during the period of 1981–2020, based on the five precipitation traits (i.e., spatial pattern of multi-year average, annual trend, seasonality, frequency, and intensity), and meteorological gauge observations are taken as the benchmark. Our results show that, compared to other products, CHIRPS data has the strongest ability to present spatial pattern of multi-year average precipitation, especially in most parts of northeastern and southern China, and ERA5 has the weakest ability to simulate the multi-year average precipitation. All four precipitation products can accurately depict the spatial pattern of seasonality, among which CHIRPS and ERA5 have the highest and lowest fitting ability, respectively, but four products poorly describe the spatial pattern of precipitation intensity and frequency at a daily scale. These products only correctly predict the interannual precipitation trend in some local areas. Our findings provide evidences to select high-quality precipitation data, and could help to improve the accuracy of relative geophysical models. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine the effect of type 2 diabetes mellitus (T2DM) on overall survival (OS) of patients with stage IIIB–IV non‐small cell lung cancer (NSCLC). Methods: We retrospectively analyzed patients with stage IIIB–IV NSCLC from January 2015 to December 2018 in the Department of Oncology at the First Affiliated Hospital of Anhui University of Traditional Chinese Medicine. Kaplan–Meier plots, log‐rank tests, and Cox proportional hazards regression models were used to describe the effect of T2DM on the OS of patients with stage IIIB–IV NSCLC. Results: This study collected data on 76 patients with NSCLC and T2DM (group A) and 214 NSCLC patients without T2DM (group B). After propensity score matching (PSM) analysis, 74 patients were included in each group. The mean OS of all patients was 17 months (range, 11–31 months). The mean OS of group A was 15 months (range, 8–25 months) and the mean OS of group B was 20 months (range, 14–39 months). The mean OS of group B was longer than group A, and the difference was statistically significant. Univariate analysis of the clinical data showed that T2DM and complications were significantly correlated with the prognosis of patients with stage IIIB‐IV NSCLC (p = 0.003 and p = 0.034). Multivariate Cox model analysis showed that T2DM and complications were independent prognostic factors for patients with stage IIIB–IV NSCLC (p = 0.002 and p = 0.024, respectively). Conclusion: Stage IIIB–IV NSCLC patients without T2DM have an increased OS compared to patients with stage IIIB–IV NSCLE and T2DM. [ABSTRACT FROM AUTHOR]

Aims: To explore the influence of nine healthy lifestyle factors on the risk of type 2 diabetes mellitus in adults in Guizhou, China. Methods: Data were obtained from a large population‐based prospective cohort study in Guizhou Province, China. A total of 7,319 participants aged ≥18 years without diabetes at baseline were included in this study and were followed up from 2016 to 2020. A healthy lifestyle score was calculated based on the number of healthy lifestyle factors. Results: During an average of 7.1 person‐years of follow‐up, 764 participants were diagnosed with type 2 diabetes mellitus. Compared with those of participants who scored 0–3 for a healthy lifestyle, the hazard ratios (95% confidence intervals) of those who scored 4, 5, 6, and ≥7 were 0.676 (0.523–0.874), 0.599 (0.464–0.773), 0.512 (0.390–0.673), and 0.393 (0.282–0.550), respectively, showing a gradual downward trend (P for trend <0.01). More importantly, they had lower fasting and 2 h post‐load plasma glucose levels and fewer changes in plasma glucose levels during follow‐up. If ≥7 healthy lifestyle factors were maintained, 33.8% of incident diabetes cases could have been prevented. Never smoking was the strongest protective factor against type 2 diabetes mellitus. Conclusions: A healthy lifestyle can effectively decrease plasma glucose levels and reduce the incidence of type 2 diabetes mellitus in adults in Guizhou, China. In addition, not smoking may be an effective way to prevent type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

In the seasonal frozen area of northeast China, cement concrete is usually in a working environment of cold climate and chlorine erosion coupling effect. In general, with a reasonable addition of air entraining agent (AEA) and multimineral admixtures such as fly ash, blast furnace slag, and silica fume, the durability of cement concrete under the effects of freeze-thaw and salt solution can be significantly improved in cold regions. However, due to several more compositions of cement concrete with multiple mineral admixtures, it would take excessive trial mixtures to select the desired mixture proportion based on the conventional method. This means a great deal of costs of raw materials and laboratory experimental time. In this paper, the experimental scheme of mixture proportion for air-entrained concrete with multimineral admixtures was designed based on the orthogonal experiment design method. Based on the compressive strength, rapid chloride permeability, and weight loss and relative dynamic elastic modulus after salt freeze-thaw cycles, the influence of different mineral admixtures and their dosages on the durability of concrete subjected to freeze-thaw in salt solution was analyzed. After that, based on genetic algorithm, an optimization of mixture proportion was proposed, which only requires less trial mixes and accessible optimization process. The test results indicated the superiority of air-entrained concrete with multimineral admixtures when serving in salt freeze-thaw environment. Eventually, it was also verified that the optimized concrete in this paper could achieve pleasurable durability performances under salt freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

The initiation and propagation of hydraulic fractures dominate the fracture morphology and conductivity, thereby determining the fracturing stimulation effect. This work took the shallow dull-type coal seam in the Hancheng block as the research object, and focused on the propagation and optimization of the H-shaped fracture. By using a combination of mechanical theoretical analysis, laboratory experiment, numerical simulation, field test, and optimization evaluation, an integrated study on the formation conditions, morphology evolution, propagation laws, main controlling factors, and optimal design of H-shaped fractures was conducted. The mechanical criterion for identifying H-shaped fracture propagation was derived through the analysis of the stress fields on the fracture surface. A 3D numerical model of H-shaped fractures was established with cohesive element method, and the propagation law and influencing factors of H-shaped fractures were investigated. Sensitivity analysis of the influencing factors on the H-shaped fractures was performed with grey incidence analysis method. The optimization of the H-shaped fracture parameters was performed by fracture propagation numerical simulation. The results show that H-shaped fractures dominated by horizontal fractures are generally formed in shallow dull-type coal seams. H-shaped fractures can improve the CBM development effect by parameter optimization of indirect fracturing technology. The judging criterion for H-shaped fracture formation is that the tensile strength of the upper and lower weakly cemented horizontal interfaces is less than that of the coal seam and the vertical principal stress is lower than the minimal horizontal principal stress. The incidence degree of fracturing fluid injection rate, viscosity, perforation location, minimum horizontal stress difference, and coal seam permeability on the H-shaped fracture propagation decreases in turn. The engineering factors (fracturing fluid injection rate and viscosity and perforation location) are the major impact factors. With the increase in coal seam permeability, the horizontal fracture develops from stubby-type to slender-type. The minimum horizontal principal stress difference mainly affects the horizontal fracture. As the fracturing fluid viscosity increases, the horizontal fracture length increases first and then decreases. The fracturing fluid injection rate has a great impact on the height-length profile of horizontal fractures. The optimal injection rate seems to be 6.5–7 m3/min, the optimal fracturing fluid viscosity is between 10 mPa·s and 15 mPa·s, and the optimal perforation location is selected near the formation interface. These research results could provide a reference for the design and optimization of efficient fracturing of coalbed methane reservoirs. • An integrated study on H-shaped fracture was conducted with multimethod combination. • Mechanical judging criterion for H-shaped fracture propagation was derived. • Numerical modeling of H-shaped fracture in dull coal seam fracturing was performed. • Sensitivity analysis of influence factors on H-shaped fracture propagation was made. • The fracturing operational parameters of H-shaped fracture were optimized. [ABSTRACT FROM AUTHOR]

The physiological metabolism of marine animals farmed in coastal areas is influenced greatly by extreme weather and frequent aqueous layer exchange, with short or long periods of heavy rain reducing seawater salinity. Black seabream (Acanthopagrus schlegelii) is a euryhaline fish, that are farmed in China under both normal/ambient salinity in seawater cages and low salinity conditions in pond culture. To explore the effects of an acute change in salinity on physiological metabolism, juvenile black seabream (weight 19.80 ± 0.37 g) was subjected to low salinity (4–5 psu) over five time points including 1 h (H1), 6 h (H6), 12 h (H12), 24 h (H24) and one week (W), with 0 h (initial, natural salinity of 22 psu) as control group. Results indicated that acute exposure to low-salinity resulted in various responses related to oxidative stress (OS) and endoplasmic reticulum stress (ERS). The key markers of OS including reactive oxygen species and malonaldehyde were significantly increased with acute salinity stress up to 6 h, then decreased to return to normal levels. A similar pattern was recorded for total antioxidant capacity, which showed significantly higher activity in the H6 group. All parameters related to ERS increased with duration of the low-salinity stress, which stimulated expression of key genes including nuclear factor kappa B (nf-κb) and c-Jun N-terminal kinase (jnk), triggering inflammation and apoptosis. However, total apoptotic cell rate decreased markedly as the duration of salinity stress increased up to one week. Gill expression of genes of long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis was up-regulated by low salinity stress with levels of docosahexaenoic (DHA), eicosapentaenoic (EPA) and arachidonic acids (ARA) being highest in the H12 group, which positively contributed to enhanced ability of osmoregulation. In conclusion, acute low-salinity stress stimulated various stress responses but, as the duration of salinity stress increased, the fish showed signs of physiological adaptation to the environmental change. During the adaptive process to maintain hemolymph osmotic pressure regulation, LC-PUFA were rapidly enriched in gill, which might be a crucial strategy allowing A. schlegelii to adapt to low-salinity stress. These findings provided further insight and understanding of the physiological responses and underlying adaptive strategy of euryhaline fish to salinity stress, and confirmed time-dependent effects. [Display omitted] • A. schlegelii showed time-dependent responses to low-salinity stress (22 to 4 psu). • LC-PUFA were enriched in gill with acute low-salinity stress. • Low-salinity caused stress responses including OS and ERS. • nf-κb and jnk were stimulated by ERS triggering inflammation and apoptosis. • A. schlegelii showed physiological adaptation to low-salinity stress. [ABSTRACT FROM AUTHOR]

[Display omitted] • Notable levels of OPA and NOPE were found in e-waste dismantling workers' hands for the first time. • The levels of NOPE were higher than those of traditional OPE on workers' hands. • The dust levels of TPHP and AO168 = O might be acceptable predictors of hand wipe levels. • Occupational exposure to NOPE via hand-to-mouth contact was more significant than dust ingestion. Electronic waste (e-waste) is a well-known source of plastic additives in the environment. However, the e-waste-related occupational exposure to organophosphite antioxidants (OPAs) and the relevant oxidation products—novel organophosphate esters (NOPEs)—via different pathways is still unknown. In this study, six OPAs and three NOPEs were measured in 116 dust and 43 hand-wipe samples from an e-waste dismantling area in Central China. The median concentrations of ΣOPAs and ΣNOPEs were 188 and 13,900 ng·g−1 in workshop dust and 5,250 ng·m−2 and 53,600 ng·m−2 on workers' hands, respectively. The increasing concentrations of dust in the form of triphenyl phosphate (TPHP) (p < 0.01) and tris(2,4-di- tert -butylphenyl) phosphate (AO168 = O) (p < 0.05) were strongly associated with the corresponding concentration on workers' hands. Furthermore, men had significantly lower levels of NOPEs on their hands than did women (p < 0.01). Moreover, the hand wipe levels of AO168 = O (41,600 ng·m−2) was significantly higher than that of the typical OPE (TPHP, 7370 ng·m−2), and the hand-to-mouth contact (ΣOPAs, 9.48 ng·kg bw-1·day−1; ΣNOPEs, 109 ng·kg bw-1·day−1) was a more significant and integrated pathway than dust ingestion (ΣOPAs, 0.10 ng·kg bw-1·day−1; ΣNOPEs, 5.01 ng·kg bw-1·day−1) of e-waste related occupational exposure to these "new" chemicals. [ABSTRACT FROM AUTHOR]

Oxyria sinensis adopts a tolerant strategy as a metal excluder to survive toxic metal concentrations. Biodiversity and the endophytic fungal community colonizing the O. sinensis roots were assessed from a mining area (MA) and a neighboring non-mining area (nMA) in southwestern China. All O. sinensis roots formed fully developed dark septate endophytes (DSEs) and arbuscular mycorrhizal fungi (AMF). Total DSE colonization was higher for the MA versus nMA, in contrast to the total AMF colonization in the two sites. The DSE colonization was higher than AMF colonization regardless of the site. Pure-culture data showed that the fungi closely related to Exophiala, Cadophora and Phialophora dominantly colonized the O. sinensis roots. A total of 450 operational taxonomic units (OTUs) were identified showing the presence of a distinct fungal community in MA and nMA, which was shaped by soil physiochemical properties, including soil Zn concentrations and organic matter. We found that O. sinensis accumulates and adapts efficiently to local endophytic fungi to achieve the expansion of its community, including the spontaneously reclaimed DSE. This property may be targeted to achieve its colonization with a pioneer plant for phytoremediation in the restoration of a vegetation cover in a metal-contaminated area. [ABSTRACT FROM AUTHOR]

Augmented reality tools and applications have been shown to have powerfully impelled the development of the field of education. In this article, the authors designed and developed an augmented reality technology-based courseware "Starry Sky Exploration—Eight Planets in the Solar System" and explored how AR can bring an immersive learning experience to students and improve students' learning effectiveness. This article presents and evaluates AR courseware applicable for the geography curriculum in secondary schools in China. In this study, 36 students from Shanghai secondary vocational school were invited to participate in the experiment, the authors use reliability analysis, regression analysis and brainwave analysis to evaluate the effectiveness of the AR course. The authors found that students have higher learning satisfaction and behavioral willingness in AR-based experiential learning activities. It can be seen that AR helps to stimulate students' interest in learning. [ABSTRACT FROM AUTHOR]

This study aimed to explore the status and influencing factors of workplace vertical violence for Chinese nursing students, and examine the relationship between the resilience and workplace vertical violence. Questionnaire survey was conducted with cluster sampling among 486 nursing students by demographic questionnaire, the Resilience Scale of University Students and Questionnaire on Nursing Students' Workplace Vertical Violence. The survey indicated that, 51.23% of nursing students have experienced workplace vertical violence; 64.3% of perpetrators were identified as assigned nurses; 65.46% and 59.44% of nursing students have respectively suffered from adverse psychological and physiological effect; and 66.67% of nursing students determined to work harder and get stronger afterwards. Besides, birthplace, education level, professional identity, sensitive personality, prior knowledge of workplace vertical violence experience before clinical practice, and resilience were the most important influencing factors of workplace vertical violence for Chinese nursing students (p < 0.05). Workplace vertical violence suffering from nurses is very common for nursing students in the clinical training. Although it has negative impacts on the psychology and physiology of nursing students, more nursing students can positively adjust themselves. Resilience plays a positive role in the nursing students' workplace vertical violence. • This study indicates that situation of workplace vertical violence suffered by nursing students is not optimistic in China. • This study identifies important risk factors of nursing students' workplace vertical violence. • Resilience plays a positive role in the nursing students' workplace vertical violence. • Most nursing students can positively adjust themselves when they are subjected to workplace vertical violence. • This study provides a certain intervention directions for the occurrence of nursing students' workplace vertical violence. [ABSTRACT FROM AUTHOR]

The three-stage acid fracturing technology is an effective technology for tight sandstone reservoirs with undeveloped natural fractures. Its filed test has achieved good results in the tight sandstone field test in the Daning block of China. The core of this technology is to complete the pump injection procedure of "conventional fracturing, acid fracturing and conventional fracturing" in sequence. However, fracture propagation behaviors vary greatly under different acidizing fracturing conditions. In this paper, the influence of different factors on the uneven degree of hydraulic fracture etching and fracture propagation was studied by triaxial hydraulic fracturing physical simulation experiment. The effects of different acid concentration, acid dosage and acid reaction time on fracture propagation behaviors were analyzed. The results show that the fractures formed by the fracturing with displacement of 160 mL/min in the laboratory did not penetrate the overburden and underburden, and longer fractures and small branch fractures were formed in the reservoir. Hydraulic fractures showed a trend of continuous expansion in the sandstone reservoir, indicating that the fracturing effect was favorable. The experimental displacement is converted to the field displacement of 8 m3/min. The influence degree of acid concentration, acid dosage, acid reaction time on fracture propagation of three-stage acidizing fracture decreases in turn. Acid concentration and acid dosage are positively correlated with the area of fracture propagation. The influence of acid injection reaction time on fracture propagation is the lowest, and the influence of acid injection reaction time on fracture propagation area is significant only in the case of high acid dosage or high acid concentration. The influence of acid immersion time on fracture permeability is far less than that of acid concentration on fracture permeability. However, the greater the acid concentration, the greater the impact of acid immersion time on fracture permeability. The experimental results can provide empirical reference for the on-site construction of the three-stage acid fracturing in tight sandstone reservoirs. • The experiment was conducted to explore the fracture propagation behaviors of three-stage acid fracturing. • The fracture permeability of under different acidification conditions was characterized. • The influence of acid dosage, acid concentration and reaction time on fracture propagation was compared and analyzed. [ABSTRACT FROM AUTHOR]

Ginsenosides, which mainly exist in rhizomes and roots of Panax notoginseng (Burk) F. H. Chen, exhibit various physiological functions and medicinal values. However, the accumulation process of ginsenosides in the rhizome, epidermis, and xylem of the main root is unknown. Herein, the temporospatial distribution and mechanism of variation of ginsenosides in the underground parts of three-year-old P. notoginseng were investigated. The results showed that the accumulation of ginsenosides in rhizomes accelerated from May. In 12-month growth stages (except May), the content of ginsenosides in the xylem and epidermis were higher than that in the rhizome. However, the ginsenosides in rhizomes increased rapidly, whereas the ginsenosides in the main root decreased from May to July. The expression levels of genes encoding squalene epoxidase, dammarenediol synthase, and uridine diphosphate-dependent glycosyltransferase (UGTPg1) in rhizomes were increased in May, whereas genes encoding squalene synthase, protopanaxadiol synthase, protopanaxatriol synthase, UGTPg45, and UGTPg29 were expressed at considerably increased levels in June. Distinct expression levels of genes related to ginsenoside biosynthesis were the main reasons for the temporospatial fluctuation of ginsenoside accumulation in the two tissues. weighted gene co-expression network analysis demonstrated that many transcripts regulated ginsenoside accumulation in underground tissues. These results provide essential data for farmers and processors participating in P. notoginseng cultivation and utilisation. • The distribution and variation of ginsenosides in Panax notoginseng. • The accumulation mechanism of ginsenosides during key period was investigated. • The ginsenosides spatial-temporal distribution and mechanism was first revealed. • Providing essential data for 6 billion RMB market of P. notoginseng in China. [ABSTRACT FROM AUTHOR]

Cancer-associated fibroblasts (CAFs) play crucial roles in enhancing cell survival, proliferation, invasion, and metastasis. We previously showed that hepatocellular carcinoma-derived CAFs (H-CAFs) promoted proliferation of hepatocellular carcinoma (HCC) cells. This study aimed to further explore the role of CAFs in HCC epithelial-mesenchymal transition (EMT) and the underlying mechanism. High CAF density was significantly associated with liver cirrhosis, inferior clinicopathologic characteristics, elevated EMT-associated markers, and poorer survival in human HCC. Within HCC cells, EMT was induced after co-culture with H-CAFs. Secretomic analysis showed that IL-6 and HGF were the key EMT-stimulating cytokines secreted by H-CAFs. Proteomic analysis revealed that TG2 was significantly upregulated in HCC cells with EMT phenotypes. Overexpression of TG2 promoted EMT of HCC cells, and knockdown of TG2 remarkably attenuated the H-CAF-induced EMT. Furthermore, during EMT, TG2 expression was enhanced after HCC cells were stimulated by IL-6, but not HGF. Inhibition of the IL-6/STAT3 signaling decreased TG2 expression. The principal TG2 transcription control element and a potential STAT3 binding site were identified using promoter analysis. Hence, H-CAFs facilitates HCC cells EMT mediated by IL-6, which in turn activates IL-6/IL6R/STAT3 axis to promote TG2 expression., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Introduction: Dioscorea species, which contain abundant steroidal saponins, have been used as folk medicines or raw materials to synthesise steroid drugs., Objective: To establish a rapid chemotaxonomic method that will comprehensively resolve confusions about genetic relationships of genus Dioscorea., Methods: A comprehensive strategy using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) was firstly proposed to evaluate the chemotaxonomy of 12 species (27 taxa) from China by hierarchical cluster analysis (HCA) based on the variations of the identified metabolites., Results: Twenty-eight secondary metabolites (mainly steroidal saponins) were identified. The MS n fragmentation patterns of DA (a new acetylated steroidal saponin at C-7 position) were firstly reported. Moreover, eight major steroidal saponins were further quantified simultaneously by UPLC-QTOF-MS method. According to HCA results, D. bulbifera L. was distinguished with species of sect. Stenophora Uline for pennogenin-type steroidal saponins. Dioscorea zingiberensis exhibited far distance from other members of sect. Stenophora Uline for two unique saponins. Dioscorea banzhuana may be reclassified into sect. Stenophora. Dioscorea nipponica subsp. rosthornii and D. collettii var. hypoglauca might be separated from their original subspecies/varieties as new species, respectively., Conclusion: The chemotaxonomic method was successfully applied in the study of genetic relationships of Dioscorea species. This study not only enhanced the understanding of chemical constituents, but also laid basic theoretical foundations for the rational utilisation and chemotaxonomy of genus Dioscorea., (© 2019 John Wiley & Sons, Ltd.)

We aimed to evaluate the association between occupational stress and PCOS risk in a Chinese population and whether insulin resistance mediates the association. A total of 366 patients with PCOS and 325 controls were included in this study. Three logistic regression analyzes were applied in statistical analysis. In the first logistic regression analysis, the occupational stress significantly influenced development of PCOS (cumulative R 2  = 0.737). In model 2, the environmental factors cumulatively accounted for 4.2% of the variance in PCOS risk. In model 3, which contained HOMA-IR, the R 2 of HOMA-IR to PCOS risk was as high as 0.41, but the R 2 of occupational stress reduced to 0.22. HOMA-IR became the main risk factor for PCOS. SEM model showed that ORQ, PSQ and PRQ had a direct and indirect effect on PCOS, and the indirect effect was through HOMA-IR. Occupational stress has a direct and indirect relationship with PCOS, which is mediated by HOMA-IR.