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Simple Summary: In this study, we provide descriptions of three fossil species, Calamites cistii, Macrostachya sp., and Punctatisporites punctatus, discovered in the Cisuralian of the eastern Hexi Corridor, northwestern China. Our findings offer insights into the evolution of Calamitaceae strobili during the Late Paleozoic. Calamitaceae was the predominant arborescent element of the Late Paleozoic plant assemblages. However, there is currently controversy surrounding the evolutionary relationships of their four reproductive organs, and there is no unified understanding of the geographical distribution and species richness characteristics. This paper is based on the detailed description of the macro- and microstructures of Calamites and Macrostachya discovered in the Shanxi Formation of the Cisuralian in the eastern Hexi Corridor of northwestern China, and it discusses the evolutionary patterns of calamitean reproductive organs. The results indicate that the current specimens can be identified as the Calamites cistii and Macrostachya sp., and the in situ spores should exhibit distinct trilete marks, indicating that they belong to the Punctatisporites punctatus. The abundant fossil records suggest that the "Calamostachys" type should be considered as the ancestral type of strobili. Additionally, Calamitaceae was widely distributed in mid to low latitudes globally from the Pennsylvanian to the Cisuralian and coupled with paleogeographic distribution characteristics. [ABSTRACT FROM AUTHOR]

Microbial metabolism directly participates in soil nutrient recycling and ecosystem stability. Although the rhizosphere soil is one of the most active habitats, information on how microorganisms acquire nutrients based on ecoenzymatic stoichiometry is lacking, especially for major food crops under field conditions. Thus, this study aimed to explore the soil nutrient properties and microbial biomass concentrations as well as extracellular enzymatic activities and focused on carbon (C), nitrogen (N), and phosphorus (P) cycling of different crop types, including potato (Solanaceae), maize (cereal), soybean (Leguminosae), and buckwheat (Polygonaceae) in the arid area of northern Shaanxi, China. Microorganisms in the rhizosphere soil of four crops were subjected to relative C and N limitation tests based on ecoenzymatic activities. Among the crops, potato and soybean exhibited the maximum limitations. Linear regression analysis of soil nutrients, microorganisms (stoichiometric homeostasis), and threshold elemental ratio synthetically supported microbial metabolic limitations. This finding coincided with the highest and lowest microbial carbon use efficiencies in soybean (0.58) and potato (0.51), illustrating the distinguishing physiological responses of microbes. Partial least squares path modeling further confirmed that the soil microbial nutrient limitations were significantly regulated by soil nutrient properties and extracellular enzyme activities. Taken together, soil microbial metabolism in agricultural ecosystems was co‐limited by relative C and N regardless of the main food crop families in this region in China (northern Loess Plateau). These observations clarified the nutrient cycling driven by soil elemental stoichiometry at the root–soil interface in arid and oligotrophic ecosystems. [ABSTRACT FROM AUTHOR]

In water ecosystems, zoobenthos are one of the most important communities. Maintenance of healthy zoobenthos community is essential for water ecosystems remediation. Understanding the hydrology and water quality factors that drive the variation of zoobenthos is the priority for water ecosystems remediation. The present study used canonical correlation analysis to select the main habitat factors affecting zoobenthic communities based on field sampling of the river zoobenthos in the first pilot city for the construction of civilized water ecosystems in China—Jinan City. In addition, analysis was performed based on geoscience methods of Global Moran's I and Anselin local Moran's I spatial autocorrelation of main habitats factors. The results show that the key water quality physical factors affecting Jinan City zoobenthic communities were pH and conductivity; the key water quality chemical factors were K+, Na+, and permanganate index; and the key hydrological factor was water depth. The sodium ions and conductivity exhibited significant spatial autocorrelation in all seasons. And the regions exhibiting spatial autocorrelation were generally stable. Moreover, the characteristics of benthic animals are closely related to human activities of domestic sewage discharge in the central and agricultural activities in northern parts of the study area. All methods in this paper can be extended to the researches on other communities, for example, algae, zooplankton, and fish in water ecosystems. The methods and results in the paper can provide significant references for managers to protect and restore degraded water ecosystems in global water. [ABSTRACT FROM AUTHOR]

Well-preserved Marattialean fertile fronds are analyzed in this paper that come from the Cisuralian Shanxi Formation of Yongchang, Gansu Province, northwestern China. In particular, synangium in fronds and in situ spores are analyzed in the lab. Data show that the synangium of this species contains between four and five radially arranged pedicellate sporangia. The spores of this plant are small, between 21 and 30 μm, monolete and microgranulate with no visible annule. The fossils presented in this study are included within the genus Cyathocarpus. Furthermore, these spore masses and spores in situ of this genus are described in detail at the first time as a component of the Cathaysian flora. Based on comparisons with previously reported fossil records of these plants, we determined a series of differences. Thus, the fossils presented here are referred to a new species. In addition, the reproductive organs of the new fossils described in this paper provide some valuable taxonomic information. Based on the paleogeographic distribution of Cyathocarpus and the position of paleoplates in Late Paleozoic, we speculated that one of the possible migrated routes of Cyathocarpus is from the Euramerica to the North China Block and Alashan Terrane, terminating in the South China Block. [ABSTRACT FROM AUTHOR]

Cervical cancer is one of the leading causes of cancer-related deaths among women and it is caused by the human papillomavirus (HPV). High variation has been reported in the attribution of specific HPV genotypes to cervical neoplasia among various geographic regions. For effective control of cervical cancer through HPV vaccination, it is essential to estimate the cost-effectiveness of vaccination, to monitor the potential transition into other HPV genotypes, and to understand the distribution of specific HPV genotypes across a specific geographic region. In this study, the distribution of HPV genotypes was investigated in southeast China, from 2011 to 2016. The 12,816 cervical swabs collected from women (age 18–78 years, median 43.6 years) outpatients were analyzed. HPV prevalence among 12,816 cervical swabs analyzed was 22.3% (2,856/12,816). Among these positive cases, 2,216 had only one HPV genotype while 640 had multiple HPV genotypes. The cases with multiple types revealed 23 different HPV genotypes with the five most prevalent being HPV18 (18.2%), HPV52 (14.1%), HPV16 (11.9%), HPV58 (10.6%), and HPV33 (5.5%). The rates of HPV infection in patients with cervical inflammation, CIN-1, CIN-2, CIN-3, squamous carcinoma, and adenocarcinoma were 38.4%, 80.5%, 82.6%, 92.3%, 97.5%, and 93.4%, respectively. Four HPV genotypes, HPV18, HPV16, HPV52, and HPV58, were more prevalent in patients with CIN-2-CIN-3 and invasive cervical cancer. A comparison of HPV genotypes attribution to cervical cancer between southeast China and global incidences revealed distinct differences. Due to this unique prevalence, it is essential to streamline the vaccination development protocol prior to administering vaccines based on global data. [ABSTRACT FROM AUTHOR]

Enriching our knowledge of Paleozoic conifers helps our understanding of plant diversification and climate change in this period. Here we report a compression conifer with well-preserved leaf twigs and seed cones discovered in the Cisuralian Shanxi Formation in Yongchang, Gansu Province, northwest China. The conifer was identified as a new genus, Hexicladia (H. yongchangensis gen. et sp. nov.), according to detailed morphological comparisons of vegetative and reproductive organs with related fossil genera of Paleozoic conifers. The vegetative shoots have helically-arranged ascending branches. The leaves are spirally arranged and broadly attached. The seed cones are terminal and erect, with several bract-scale complexes around the cone axis. The new fossil is assigned to the Voltziales, based on its whole architecture, and its similarities to some "walchian" conifers. Nevertheless, the discovery of Hexicladia gen. nov. adds to our knowledge of Paleozoic conifers, and reveals that conifers had already evolved complex features in the early Permian. • A new Paleozoic conifer is described from the Cisuralian, northwest China. • This new genus bears ascending branches, with spirally arranged leaves and terminal seed cone. • The seed cone comprises several bract-scale complexes around the cone axis. • The new genus reveals conifers had evolved complex features by the early Permian. [ABSTRACT FROM AUTHOR]

Suicide hotlines are widely used, with potential for identification of callers at especially high risk. This prospective study was conducted at the largest psychological support hotline in China. From 2015 to 2017, all distressed callers were consecutively included and assessed, using a standardized scale consisting of 12 elements, yielding scores of high risk (8–16), moderate risk (4–7), and low risk (0–3) for suicidal act. All high-risk and half of moderate- and low-risk callers were scheduled for a 12-month follow-up. Main outcomes were suicidal acts (nonlethal attempt, death) over follow-up. Of 21,346 fully assessed callers, 5822, 11,791, and 3733 were classified as high-, moderate-, or low-risk for suicidal acts, with 8869 callers (4076 high-, 3258 moderate-, and 1535 low-risk) followed up over 12 months. Over follow-up, 802 (9.0 %) callers attempted suicide or died by suicide. The high-risk callers (15.1 %) had 3-fold higher risk for subsequent suicidal acts than moderate- (5.1 %) and 12-fold higher risk than low-risk callers (1.3 %). The weighted sensitivity, specificity, and positive predictive value of high risk scores were 56.4 %, 74.9 %, and 14.4 %. Assessed callers with different risk levels were followed disproportionally. Suicidal risk assessment during a hotline call is both feasible and predictive of risk, guiding resource allocation to higher risk callers. • A comprehensive suicidal risk assessment scale for suicide prevention hotline has been developed. • Of 21,346 fully assessed hotline callers, 8869 callers were followed up over 12-month. • Findings of this prospective study indicate that predictive validities of the scale are acceptable. • Suicidal risk assessment is viable for determination of intervention plan in hotline in resources-limited countries. [ABSTRACT FROM AUTHOR]

Alpine wetland ecosystems are of importance in water conservation and animal husbandry in the arid central Asian. However, there is limited research on their formation and relationship with climate. In this study, we evaluated the long-term interactions of vegetation, hydrology, and climate based on multiple proxies (lithology, grain size, loss-on-ignition (LOI) at 550 °C, and pollen) obtained from a sediment core (BY10A) from Lake Swan, an alpine lake in the central Tianshan Mountains of northwest China (2541 m a.s.l.). Our records show that Holocene sediment facies change considerably within core BY10A, with the succession from bottom to top comprising fluvial, peat, and lake sediments. The fluvial deposits were characterized by coarser sediment, which was probably reworked from extensive sand dunes developed over the basin during the early Holocene (12.0–7.5 cal kyr BP). Regional biological productivity was low at this time as indicated by the low LOI value, and the remains of vegetation was degraded under the dry climate. A warm and wet climate prevailed from 7.5 to 2.0 cal kyr BP, resulting in the establishment of peat. The ability of the peat surface to efficiently trap fine particles was enhanced when regional sand dune bodies (coarser part) became largely stabilized by vegetation growth in response to increases in moisture availability. After 2.0 cal kyr BP, a rise in water level, leading to the formation of Lake Swan, indicated a further shift to a wetter climate. During this interval, there was an increasing influence of lacustrine settling and/or wave action on the grain size distribution and the pollen assemblage. This study indicates a stepwise wetting trend from the early to late Holocene. Findings show that changes in moisture, regulated by the prevailing westerlies, exerted a significant influence on the evolution of vegetation communities and lake level in our study area. Schematic figure showing the Holocene hydroclimate changes in an alpine lake in the central Tianshan Mountains, northwest China. During the early Holocene (12–7.5 cal kyr BP), low biological productivity and vegetation cover reflect a dry climate and correspond to a fluvial depositional environment (a). Subsequently, the development of peat sediments and increases in biological productivity and vegetation cover indicate optimum climate conditions during the mid to late Holocene (7.5–2.0 cal kyr BP) (b). After 2.0 cal kyr BP, a rise in water level, leading to the formation of Lake Swan, indicates conditions of increased moisture. During this interval, there was an increasing influence of lacustrine settling or wave action on the grain size distribution and pollen assemblage (c). [Display omitted] • Multiple proxies were used to evaluate long-term changes in vegetation, hydrology, and climate. • Variations in proxies were highly correlated with depositional processes. • A stepwise wetting trend occurred in the Tianshan Mountains from the early to late Holocene. • Changes in moisture regulated by the westerlies influenced the hydroclimate in our study area. [ABSTRACT FROM AUTHOR]

The present study aims to investigate temporal evolutions of particulate matter (PM) concentrations and its association with the meteorology and aerosol optical depth (AOD) during autumn and winter of 2014–2017 at an urban city, Nanjing in the Yangtze River Delta, East China. The seasonal mean PM 2.5 (PM 10) was found maximum and minimum with 81.2 ± 41.5 μg m−3 (135.6 ± 57.1 μg m−3) and 33.7 ± 19.1 μg m−3 (65.8 ± 34.5 μg m−3) during winter and autumn seasons, respectively. Furthermore, the mean ratio of PM 2.5 /PM 10 was around ~0.57 for the entire study period, with a lower contribution (0.53) in autumn and higher (0.60) in winter. However, the seasonal mean AOD 440 , precipitable water vapor content, Ångström exponent (AE 440-870) was found maximum with 0.97 ± 0.31, 1.58 ± 0.80 cm, and 1.14 ± 0.23 during autumn, and a minimum of 0.62 ± 0.34, 0.60 ± 0.27 cm, and 1.29 ± 0.19 in winter, respectively. The potential source contribution function (PSCF) and concentration weighted trajectory (CWT) models revealed considerable long-distance transport of PM 2.5 from north and northwest China. Besides, the concentration bivariate probability function (CBPF) revealed a significant contribution of PM 2.5 occurred when the winds blown from southerly and northwesterly directions. The relationship between PM 2.5 and meteorology found that PM 2.5 concentration had a positive relationship with AQI, while negative correlations with the major meteorological parameters. A notable spatial heterogeneities and trends were observed in AOD and AE, with negative correlations (−0.5 to 0) in winter over East China. Image 1 • Quantification of PM concentrations and air quality during autumn and winter seasons. • The concentrations of PM 2.5 found maximum in winter relative during autumn. • AOD showed high in autumn clearly demonstrates negative correlation with PM. • The CWT analysis revealed a significant contribution to PM during winter. • The meteorological variables showed negative relationship with PM in all seasons. [ABSTRACT FROM AUTHOR]

The combination of straw returning and nitrogen (N) fertilization is a popular tillage mode and essential strategy for achieving stable yield and high quality. However, the optimal combination strategy and the influence of tillage mode on the morphological, crystalline, and molecular structures of maize starch remain unclear. We conducted a long-term field experiment over 7 years in Northeast China using two tillage modes, rotary tillage with straw returning (RTS) and plow tillage with straw returning (PTS), and four N application rates. The relative crystallinity, 1045/1022 cm -1 value, and B2 and B3 chains of maize starch were higher under RTS than under PTS, resulting in increased stability of starch and improvements in gelatinization enthalpy and temperature. The surface of the starch granules induced by N fertilizer was smoother than that under the N0 (0 kg N ha -1 ) treatment. The proportion of amylose content, solubility, swelling power, and light transmittance increased under N2 (262 kg N ha -1 ) treatment, along with improvement in starch pasting properties. These results suggest that RTS combined with N2 treatment can regulate the morphological, structural, and physicochemical characteristics of maize starch, providing an essential reference for improving the quality of maize starch from an agronomic point of view., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Quantitatively and accurately analyzing nonpoint-source (NPS) pollution is essential for efficiently preventing the input of NPS loads into inland waters. However, the accuracy of previous NPS pollution models is limited by the accuracy of ground parameter data. In addition, there are few effective methods that thoroughly verify modeling results at large scales. This paper presents a framework for accurate NPS pollution estimation by coupling satellite and unmanned aerial vehicle (UAV) monitoring data, and the results are verified by both field sampling and a newly developed inlet NPS pollution "observation" simulation method. Fractional vegetation coverage (FVC) data obtained by satellite were used to improve the accuracy of the runoff module of the framework. Satellite and UAV data were coupled to acquire livestock data, determine inlets, and identify reservoir buffer zones and vegetation types. These new data were then used to improve the accuracy of the livestock and runoff modules in the framework. The results show that the estimation accuracy of total nitrogen, total phosphorus, ammonia nitrogen, and chemical oxygen demand with FVC were improved by 39.96%, 69.29%, 54.05% and 47.22% (in relative error), respectively. The high-resolution livestock data acquisition improved the estimation accuracy of the NPS pollution load by 7-53%. The high-resolution inlet extraction improved the accuracy by 3-24%. The high-resolution buffer zone identification improved the accuracy with the estimated NPS pollutant concentration into reservoir decreasing by 60-99%. Finally, the high-resolution vegetation type identification improved the accuracy by 10-72%. The framework performs satisfactorily, which was verified based on the simulated NPS observations with an average relative error of 11.54-24.31%. We found that the FVC, livestock number, and inlet number are key parameters for NPS pollution modeling; the introduction of monthly variation in the FVC makes the modeled NPS pollution load much higher in areas with mature complex forested ecosystems or densely distributed vegetation but much lower in areas with sparsely distributed vegetation. The above methods provide a scientific reference for high-efficiency NPS pollution prevention in inland waters, laying a solid basis for decision-making regarding water quality management in data-scarce regions around the world., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Previous studies have described the correlation of suicidal ideation (SI) or suicide attempts (SA) in people living with HIV (PLWH), whereas few studies compare the correlation between SI and SA in PLWH. Understanding specific risk factors for SI and SA among PLWH will help with developing tailored and effective suicide prevention strategies among this high-risk group., Methods: A cross-sectional study was conducted from December 2020 to April 2021 in Baoji municipality, Shaanxi Province. The PLWH registered with the Baoji Municipal Center for Disease Control and Prevention (CDC) were recruited and interviewed. Questionnaires and interviews for this study consisted of socio-demographic variables, mental health history, and psychosocial characteristics. The HIV-related clinical features were obtained from CDC medical records. The PLWH included were divided into three groups, i.e., those with a history of suicide attempts (SA group), those with suicidal ideation only (SI group), and those without any suicidal behavior (NSB group). Multinomial logistic regression was used for three-way comparisons among these three groups of PLWH., Results: In total, 995 PLWH were interviewed. The prevalence of probable depression, probable anxiety, SI, and SA in PLWH after being diagnosed as HIV+ was 18.6%, 13.5%, 26.7%, and 3.2%, respectively. Compared with the NSB group, the SI or SA groups were more likely to report probable depression [adjusted odds ratio (AOR) = 2.43, 4.44, respectively], probable anxiety (AOR = 2.80, 5.62, respectively), and high HIV-related stigma (AOR = 2.05, 2.65, respectively). The SI group was more likely to experience high HIV-related stress (AOR = 1.91) and lower quality of life (AOR = 0.56) than the NSB group. Social support and HIV-related clinical features were not associated with SI or SA in this sample. The SA group did not differ from the SI group on any of the psychosocial or HIV-related clinical features., Conclusions: Mental health problems are serious in community residents identified with having an HIV infection in a Central West China municipality. It is important to deliver low-cost and effective psychological services tailored for PLWH that are focused on reducing mental health problems. Future studies should utilize sensitive screening measures and further clarify factors potentially associated with the transition from SI to SA in PLWH., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Yan, Tong, Gao, Zhou, Lan, Wu, Li, Yin, Wang, Liu and Deng.)

Background and Aim: To observe the clinical value of hepatitis C virus (HCV) core antigen (HCcAg) levels in monitoring acute HCV infection in patients with spontaneous clearance (SC) or clearance induced by antiviral therapy., Methods: Patients with iatrogenic HCV infection (n = 104) were enrolled at the Shengjing Hospital, China Medical University, between 5 February 2013 and 3 April 2013. All cases were diagnosed with acute HCV infection, enrolled within 90 days of infection, and followed for 12 to 16 weeks. Blood was collected every month. HCV RNA and HCcAg levels were detected. From week 16, patients without SC were treated with pegylated-interferon and the HCV RNA and HCcAg levels were observed monthly. Follow-up was 7.5 (5.0 to 10.4) months. The Spearman correlation analysis was performed to determine the correlation between HCV RNA and HCcAg. Logistic regression analysis was used to determine the association of baseline HCV RNA and HCcAg levels with SC., Results: Ten patients (9.62%) showed SC, with a negative conversion time of 57 (14 to 143) days. During follow-up, HCV RNA and HCcAg expression levels were positively correlated for each patient (except on the sixth month), but the levels of HCV RNA and HCcAg were not associated with HCV infection SC., Conclusions: HCcAg levels could be of value for monitoring the course early HCV infection, but could not predict SC of HCV infection., (© 2018 Wiley Periodicals, Inc.)