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Nitrogen addition has been shown to affect plant litter decomposition in terrestrial ecosystems. The way that nitrogen deposition impacts the relationship between plant litter decomposition and altered soil nitrogen availability is unclear, however. This study examined 18 co-occurring litter types in a subtropical forest in China in terms of their decomposition (1 yr of exposure in the field) with nitrogen addition treatment (0, 0.4, 1.6, and 4.0 mol·N·m−2·yr−1) and soil fauna exclusion (litter bags with 0.1 and 2 cm mesh size). Results showed that the plant litter decomposition rate is significantly reduced because of nitrogen addition; the strength of the nitrogen addition effect is closely related to the nitrogen addition levels. Plant litters with diverse quality responded to nitrogen addition differently. When soil fauna was present, the nitrogen addition effect on medium-quality or high-quality plant litter decomposition rate was −26% ± 5% and −29% ± 4%, respectively; these values are significantly higher than that of low-quality plant litter decomposition. The pattern is similar when soil fauna is absent. In general, the plant litter decomposition rate is decreased by soil fauna exclusion; an average inhibition of −17% ± 1.5% was exhibited across nitrogen addition treatment and litter quality groups. However, this effect is weakly related to nitrogen addition treatment and plant litter quality. We conclude that the variations in plant litter quality, nitrogen deposition, and soil fauna are important factors of decomposition and nutrient cycling in a subtropical forest ecosystem. [ABSTRACT FROM AUTHOR]

Background: Plants can directly affect litter decomposition by producing litter materials of different qualities. However, whether living plants have indirect effects on litter decomposition by affecting changes in forest microenvironments is presently unclear in plantation forests. Methods: We addressed this issue by studying the decomposition of the leaf litter and fine roots of Chinese fir [Cunninghamia lanceolata (Lamb.) Hook.], a timber species widely planted in China, in 113 non-neighboring quadrats of varying basal area of the dominant plant species (i.e., Chinese fir) and distinct basal areas and species richness of regenerated woody plants (i.e., species other than Chinese fir) in a subtropical Chinese fir forest. Results: Our results showed that fine roots decomposed significantly more rapidly than leaf litter possibly because fine roots were easier access to mineralized nutrients and microbes compared with leaf litter. Further analyses showed that leaf litter and fine root decomposition rates were significantly controlled by the plant community attributes. The decomposition of both leaf litter and fine roots was mainly controlled by woody species regenerated during stand development rather than by Chinese fir. Specifically, leaf litter and fine root decomposition rates decreased with increasing basal area of regenerated woody plants, possibly due to nutrient competition and/or reduced photodegradation. Conclusions: This study provides empirical evidence that woody species regenerated during stand development play a certain role in determining litter decomposition rates through plant-soil interactions in Chinese fir plantations. Regenerated woody plants should be considered in future studies on soil carbon and nutrient cycling in plantation forest. [ABSTRACT FROM AUTHOR]

Highlights: [•] Most litter-C was converted into CO2 during decomposition. [•] Litter-C changed the decomposition rate of native soil organic carbon. [•] The effects of inorganic N addition on the fates of litter-C depend on the inorganic N form. [ABSTRACT FROM AUTHOR]

Abstract: Soil organic carbon (SOC) dynamics and nutrient availability determine the soil quality and fertility in a Chinese fir plantation forest in subtropical China. Uniformly 13C-labeled Chinese fir (Cunninghamia lanceolata) and alder (Alnus cremastogyne) leaf litter with or without 100mg NH4 + or NO3 − were added to the soil. The purpose was to investigate the influence of N availability on the decomposition of the litter and native SOC. The production of CO2, the natural abundance of 13C–CO2, and the inorganic N dynamics were monitored. The results showed that Chinese fir (with a high C:N ratio) and alder (with a low C:N ratio) leaf litter caused significant positive priming effects (PEs) of 24% and 42%, respectively, at the end of the experiment (235d). The PE dynamics showed that positive PE can last for at least 87d. However, the possible occurrence of a significant negative PE with a sufficient incubation period is difficult to confirm. The application of both NH4 + and NO3 − was found to have a stimulating effect on the decomposition of Chinese fir and alder leaf litter in the early stage (0–15d) of incubation, but an adverse effect in the late stage. Compared with NO3 −, NH4 + caused a greater decrease in the PE induced by both Chinese fir and alder leaf litter. The effects of NH4 + and NO3 − on the PE dynamics had different patterns for different incubation stages. This result may indicate that the stability or recalcitrance of SOC, especially in such plantation forest soils, strongly depends on available leaf litter and application of N to the soil. [Copyright &y& Elsevier]

Objective To determine the prevalence of HIV-1, syphilis, relative factors associated with HIV-1 and syphilis infection among drug users in China. Methods Chinese HIV/AIDS comprehensive surveillance is a routine work; the data on drug users in 2005 were analysed; HIV-1 and syphilis antibody status was obtained from blood tests; demographic and behavioural data were collected through standardized interviews. Logistic regression was used to analyse independent association between HIV-1 and syphilis status and risk behaviours. Results HIV-1 antibody prevalence was 5.0% ,with large regional differences. Syphilis positive rate was 2. 8%. Logistic regression analysis showed demographic and behavioural factors significantly associated with HIV prevalence were: minority versus Han-Chinese (OR 4.10; P <0.001), education ≤9 years versus >9 years (OR 1.61; P = 0.001), IDU with needle-sharing versus non-IDU (OR 4.44; P <0.001); demographic and behavioral factors significantly associated with syphilis prevalence were : sample source detoxification center versus others (OR 3.49; P < 0.01), female versus male (OR 5.14; P <0.001), education ≤9 years versus >9 years (OR 2.27; P <0.001). Conclusion HIV-1 prevalence among drug users in China is relatively high (5%) and the risk of HIV-1 infection is associated predominantly with minority status, low education and injecting drug use. Special interventions among drug users in China are strongly warranted. [ABSTRACT FROM AUTHOR]

Summary: Objectives: To determine the state of HIV infection, its secular trends and influencing factors in a village central China with a high prevalence rate of blood-borne AIDS. Methods: HIV screening in WY village was carried out. Results: The rate of paid blood donors in WY village was found to be 36.3% (466/1285). The HIV infection rate was 15.3% (197/1285). Among 197 HIV positive cases, 80 (40.6%) were infected through paid blood donation, four (2.0%) were infected through sexual activity, seven cases (3.6%) were infected through mother-to-child transmission, one case (0.5%) was infected through transfusion, and one (0.5%) was infected through nosocomial infection. In 100 cases (50.8%) the infection route could not be identified, however, based on their history of paid blood donation, their age, and the chance of becoming infected with HIV through paid blood donation, it is likely that most of these 100 cases were infected by paid blood donation. In the final four cases the method of transmission could not be determined. Of the infected women of reproductive age only 1.9% (2/103) had the intention to conceive. In the cases of HIV status conflicting spouses, 51.7% (30/58) did not consistently use condoms. Conclusions: The main route of HIV transmission was found to have been paid blood donation in the past, and will be by sexual means in the future. [Copyright &y& Elsevier]

Most cities in China are experiencing severe air pollution due to rapid economic development and accelerated industrialization. Exposure to various air pollutants has been related to acute exacerbations of chronic obstructive pulmonary disease (AECOPD). However, less is known about the spatial association between air pollution and AECOPD hospitalizations in the Yangtze River delta (YRD) economic and industrial region. Jinhua city is located in the YRD region of East China, in the middle of Zhejiang province. For the first time, 1563 AECOPD hospitalization cases in Jinhua during 2019 were enrolled in our analysis. The spatial distribution of six pollutants (SO 2 , CO, PM10, PM2.5, O 3 , NO 2) and the population temporal-spatial specific air pollutant exposure levels were estimated using the ordinary Kriging model through geographic information system (GIS). Global Moran's I was used to explore the spatial association between ambient air pollutants and AECOPD hospitalizations. The Z-scores of residential SO 2 , CO, PM10, PM2.5, O 3 , and NO 2 levels were 31.88, 42.95, 45.90, 32.29, 52.18, and 34.59, respectively. The concentrations of six monitored pollutants and AECOPD hospitalizations showed statistically significant spatial clustering. A generalized linear model (GLM) using a Poisson distribution with the log-link function was used to construct a core model. After adjusting for potential confounders in the model, residential SO 2 , NO 2 and O 3 concentrations were significantly associated with increased AECOPD hospitalizations. Image 1 • Ambient air pollution is correlated with AECOPD hospitalizations spatially in Jinhua city, 2019. • SO 2 , CO, PM10, PM2.5, O 3 , and NO 2 were evaluated. • O 3 levels are most highly spatially correlated with AECOPD hospitalization. • GIS is a powerful tool to analyze the spatial association between air pollution and respiratory illness. [ABSTRACT FROM AUTHOR]

Background. Hepatocellular carcinoma (HCC) is one of the most common malignancies globally, but its molecular mechanism is unclear. Abnormal expression of centromere protein U (CENPU) is closely related to diverse human cancers. The purpose of this article was to evaluate the function and potential mechanisms of CENPU in HCC development. Methods. We performed bioinformatics analysis of The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Gene Expression Profiling Interactive Analysis (GEPIA), and Kaplan-Meier plotter databases to investigate the clinical significance and prognostic value of CENPU in HCC. Western blotting and immunohistochemical staining were used to measure protein expression, while reverse transcription-quantitative polymerase chain reaction (qRT-PCR) was used to determine mRNA expression. Cell Counting Kit8 (CCK-8) and colony formation assays were conducted to examine cell proliferation. Transwell and wound healing assays were used to assess cell migration and invasion. Gene set enrichment analysis (GSEA) was used to explore the potential signaling pathways of CENPU involved in HCC. Results. High expression of CENPU in HCC was predicted by public database analysis and indicated a poor prognosis. CENPU expression was significantly higher in HCC tissues and cells than in normal tissues and cell. In vitro, CENPU promoted the proliferation, migration, and invasion of HCC cells. GSEA results indicated that CENPU was linked to the Notch signaling pathway, and our research supported this prediction. Conclusion. CENPU promotes the malignant biological process of HCC and may be a promising target for HCC treatment. [ABSTRACT FROM AUTHOR]

In this study, we use the strong motion records and seismic intensity data from 11 moderate-to-strong earthquakes in the mainland of China since 2008 to develop new conversion equations between seismic intensity and peak ground motion parameters. Based on the analysis of the distribution of the dataset, the reversible conversion relationships between modified Mercalli intensity (MMI) and peak ground acceleration (PGA), peak ground velocity (PGV), and pseudo-spectral acceleration (PSA) at natural vibration periods of 0.3 s, 1.0 s, 2.0 s, and 3.0 s are obtained by using the orthogonal regression. The influence of moment magnitude, hypocentral distance, and hypocentral depth on the residuals of conversion equations is also explored. To account for and eliminate the trends in the residuals, we introduce a magnitude-distance-depth correction term and obtain the improved relationships. Furthermore, we compare the results of this study with previously published works and analyze the regional dependence of conversion equations. To quantify the regional variations, a regional correction factor for China, suitable for adjustment of global relationships, has also been estimated. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the coverage and willingness of pneumococcal vaccination and further explore the influencing factors of vaccination willingness among people in mainland China.Methods: Literature searches were conducted independently by two researchers in English- and Chinese-language databases from database inception to 6 October 2021. A random-effects meta-analysis model was used to derive summary vaccination coverage and willingness. Predefined subgroup analysis and meta-regression were performed to explore the sources of heterogeneity.Results: A total of 97 studies were included in this meta-analysis. The summary vaccination coverage in 76 included studies was 21.7% (95% confidence interval [CI]: 17.2%-26.5%). Subgroup analysis shows that the summary coverage was 29.0% (95% CI, 20.4%-39.1%) among the permanent residents and 20.7% (95% CI, 12.4%-35.9%) among the floating residents. The eastern and central regions presented higher coverage than the western region. Notable differences were observed between the various study populations. A total of 27 studies provided an estimation of vaccination willingness, with a summary willingness of 51.2% (95% CI, 40.4%-61.9%). In subgroup analysis, the summary willingness was 57.9% (95% CI, 48.3%-67.2%) in urban areas and 52.3% (95% CI, 40.8%-63.8%) in rural areas. Parents with children and people with a history of pneumonia were more willing to be vaccinated than the elderly. Recommendations by family members and physicians, previous pneumococcal and influenza vaccination, perceived vaccination effectiveness and severity of disease and a history of pneumonia contributed to vaccination willingness.Conclusions: Compared to global estimates and other countries, pneumococcal vaccination coverage and willingness are at a lower level in mainland China. Recommendations for vaccination by family members and doctors, a history of vaccination and the perception of pneumonia and vaccination are associated with greater willingness to be vaccinated. [ABSTRACT FROM AUTHOR]

Plant functional traits can serve as indicators of plant resource-use strategies in response to environmental changes. Plants growing in acidified soil exhibit conservative traits and limit growth, but there is still little known about changes in above- and belowground functional traits and their coordination under alleviation of soil acidification. Here, we conducted a pot experiment on raising soil pH by liming in Chinese fir (Cunninghamia lanceolata) saplings in southern China. The experiment involved in two degrees of acidified soil (Mild, pH = 4.3; Severe, pH = 3.6) and three liming treatments: Control (CK, 0), low liming treatment (L, 1000 kg CaO hm−2) and high liming treatment (H, 4000 kg CaO hm−2). We measured 22 above- and belowground functional traits of Chinese fir including allocation, morphological, photosynthetic, and chemical traits to assess their response to liming. The results show that liming enhanced aboveground mass fraction and total leaf area (TLA), and reduced construction cost (lower C concentration). However, specific leaf area (SLA), nutrient concentrations of N and P, and photosynthetic rate (Pn) remained unchanged. These results suggest that aboveground components exhibited acquisitive strategies in response to liming with greater TLA and lower construction cost. Moreover, liming reduced root mass fraction (RMF), increased specific root length (SRL), specific root area (SRA), and root N and Ca nutrient concentrations. These results suggest that belowground components also exhibited acquisitive strategies through constructing longer and thinner roots with greater metabolic rates. Our findings show that liming shifts above- and belowground resource-use strategies of Chinese fir from conservative to acquisitive. These changes in functional traits support the ability of Chinese fir to grow rapidly in response to alleviation of soil acidification. Our research not only contributes to a deeper understanding of plant adaptation mechanisms in the face of environment changes but also provides valuable insights for improving carbon sequestration of plantations in subtropical China. • 22 functional traits of Chinese fir were measured to assess their response to liming. • Liming elevated total leaf area and reduced leaf construction cost. • Liming elevated specific root length, specific root area and root N concentration. • Liming shifts resource-use strategies of Chinese fir towards acquisitive. [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: To elucidate the mechanisms of Gong Qing Decoction(GQD) on human trephocytes and decidual cells in vivo based upon the effective practice of alleviating uterine bleeding in RU486 medical abortion. Materials and methods: 90 intrauterine pregnancy women within 7 weeks, presenting for elective termination of pregnancy, were divided into the GQD-RU486 group, the RU486 group and the vacuum aspiration group. Duration of uterine bleeding was recorded and volume of uterine bleeding was measured by the method of alkaline hematin photometric. Ultramicrostructure of trephocytes and decidual cells were observed with transmission electron microscope (TEM), and apoptosis rate (AR) was assessed by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay. At the same time, immunohistochemical staining was performed and integral optical density was analyzed to evaluate the protein expression of Fas, FasL, Caspase-8 and Caspase-3 in both trephocytes and decidual cells preliminarily. Results: In comparison with the RU486 group and the vacuum aspiration group, both the duration and volume of uterine bleeding decreased significantly in the GQD-RU486 group. At the same time, both trephocytes and decidual cells in the GQD-RU486 group showed typical character of apoptotic ultramicrostructure and displayed up-regulated apoptosis rate. Synchronously, the integral optical density showed increased protein expression of Fas, FasL, Caspase-8 and Caspase-3 in both trephocytes and decidual cells in the GQD-RU486 group compared with other groups. Conclusion: These data suggest that GQD can alleviate uterine bleeding effectively in RU486 medical abortion by way of apoptosis induction. The apoptosis enhancement of RU486 by GQD may be attributable to the activation of Fas and FasL. [Copyright &y& Elsevier]

• Effect of wollastonite addition on SOC mineralization is evaluated. • Wollastonite addition increases SOC mineralization. • Greater wollastonite effect occurs on soils with lower pH values. • Soil trait change account for SOC mineralization response to wollastonite addition. Enhanced rock weathering through adding silicate rock powder to soil has been increasingly considered as an effective means of removing CO 2 from the atmosphere. However, the potential impact of silicate rock powder addition on the stability of soil organic carbon remains largely unknown, which adds an uncertainty to its effectiveness in mitigating atmospheric CO 2. In this study, the response of soil CO 2 efflux to wollastonite addition was evaluated for 12 land-use types in a subtropical region of China through an incubation experiment. Results showed that wollastonite addition significantly (P < 0.05) increased soil CO 2 efflux over the control by an average of 330.97 ± 29.25% during the incubation period. Approximately 90% of the variance in soil CO 2 efflux was explained by soil properties in this study. Increased soil pH, dissolved organic carbon and available silicon induced by wollastonite addition were the main reasons responsible for the increase in soil CO 2 emission. Soils having lower pH values responded to wollastonite addition with a higher increase in CO 2 emissions. Based on numerous land-use types, our study showed that wollastonite application will cause substantial increase in the mineralization of soil organic carbon in acidic soil, which may weaken the effectiveness of enhanced rock weathering strategies as a tool for CO 2 sequestration. [ABSTRACT FROM AUTHOR]

• A passive subambient daytime radiative cooling (PSDRC) coating was prepared. • The superamphiphobic topcoat had contact angles > 150° and sliding angles < 10°. • The different PSDRC roofs showed subambient cooling effects under direct sunlight. • The net energy reduction of the PSDRC-coated buildings was impressive. • The solar reflectance of the coating was reduced by 0.005 after dirt-resistance tests. • The solar reflectance of the coating was reduced by 0.021 after accelerated aging tests. In this study, a super-amphiphobic passive sub-ambient daytime radiative cooling (PSDRC) coating was applied to various buildings in different climatic regions in China. Irrespective of sunny, cloudy, and rainy weather conditions, the roof and west-facing wall surfaces coated with the PSDRC coating exhibited distinct sub-ambient cooling effects. Compared with the cool-white and grey roof surface temperatures, the roof surface temperature due to PSDRC coating was lower by 10.1 °C and 33.1 °C, respectively. Consequently, the room interior temperatures of different buildings were lower than the ambient air temperature during the day because of heat conduction and convection. The room with a window coated by the PSDRC coating had 18.2 °C lower interior temperature than that with a west-facing glass window. Thus, the PSDRC coating decreased the cooling energy consumption of buildings in the summer but increased the heating energy consumption in the winter. However, the net energy savings were considerable because of low solar irradiance and high heating energy demand when the sub-ambient cooling effect was diminished, which minimised the difference between the roof surface and room interior temperatures of the PSDRC and control buildings. After five-cycle dirt resistance tests, the solar reflectance of the super-amphiphobic PSDRC coating was reduced only by 0.0051. After 2000 h of artificial accelerated weathering tests, the solar reflectance of the superamphiphobic PSDRC coating was attenuated by 0.021 on average. This indicates the significance of the super-amphiphobic self-cleaning capability, which endowed the coating with a long-term sub-ambient cooling effect. [ABSTRACT FROM AUTHOR]

Abstract: Total mercury (THg) and methylmercury (MeHg) were measured in large number of soil samples collected from areas with different types of land use, different depth in the Pearl River Delta (PRD) of South China. THg and MeHg concentrations ranged from 16.7 to 3320ngg−1 and 0.01 to 1.34ngg−1, respectively. THg levels are highest in the top 0–20cm soil layer, and decrease from the surface to bottom layer soil. Spatial variation was observed with different types of land use. Urban parks had the highest concentrations and the other areas tended to decrease in the order of residential areas, industrial areas, vegetable fields, cereal fields, and woodlands. Temporal variation was also noted, and two relatively high THg contamination zones located in the northwestern part of the PRD have significantly expanded over the last two decades. Both THg and MeHg concentrations were correlated significantly with soil organic matter (OM), but not with soil pH. THg pollution status was evaluated using two assessment methods. [Copyright &y& Elsevier]

Abstract: Aim of the study: Huang-Lian-Jie-Du-Tang (HLJDT) is a traditional Chinese medicine with anti-inflammatory use. In the present study, the effects of its component herbs and pure components were observed on eicosanoid generation to find out the contributory components and their precise targets on arachidonic acid (AA) cascade. Materials and methods: By monitoring leukotriene B4 (LTB4), 5-hydroxyeicosatetraenoic acid (5-HETE), and 12-hydroxy-5,8,10-heptadecatrienoic acid (12-HHT), we compared the effects of HLJDT, HLJDT free of one or two component herbs, and water extract of four single component herbs of HLJDT (Rhizoma coptidis, Radix scutellariae, Cortex phellodendri and Fructus gardeniae) on eicosanoid generation in rat elicited peritoneal macrophages. In addition, thirteen pure compounds from HLJDT (baicalin, baicalein, wogonoside, wogonin, berberine, magnoflorine, phellodendrine, coptisine, palmatine, jateorrhizine, crocin, chlorogenic acid, and geniposide) were tested in the macrophages. Furthermore, the efficacies of these thirteen compounds were evaluated on cell-free purified enzymes: leukotriene A4 hydrolase (LTA4H), 5-, 15-lipoxygenase (5-, 15-LO), and cyclo-oxygenase-1/2 (COX-1/2). Moreover, the possible synergetic effect on LO pathway derived LTB4 generation between the active components was also tested in rat peritoneal macrophages. Results: Our experiments showed that Rhizoma coptidis and Radix scutellariae were responsible for the suppressive effect of HLJDT on eicosanoid generation. Some of the pure components including baicalein, baicalin, wogonoside, wogonin, coptisine, and magnoflorine inhibited eicosanoid generation in rat macrophages via LO pathway of AA cascade. Further experiments on cell-free purified enzymes confirmed that Radix scutellariae derived baicalein and baicalin showed significant inhibition on 5-LO and 15-LO, while Rhizoma coptidis derived coptisine showed medium inhibition on LTA4H. On the other hand, no significant inhibition of thirteen components on COX-1/2 was observed. Moreover, the slight synergetic inhibition on LTB4 between baicalein and coptisine was proved in the rat peritoneal macrophages. Conclusions: Baicalein and coptisine, the active components of HLJDT, for the first time are found to interfere with arachidonic acid cascade via inhibition on different points of LO pathway. This finding makes the mechanism of HLJDT clearer and achieves its safer therapeutic application. [Copyright &y& Elsevier]

Abstract: Aim of the study: Tanshinone IIA (T), salvianolic acid B (S) and ginsenoside Rb1 (G) are the three major active ingredients of Compound Danshen Formula (CDF) for its protective effects on myocardial ischemia (MI). In this study, we aimed to investigate therapeutic and synergistic effects of TSG (combination of T, S and G) on MI rats with metabolomic strategy. Materials and methods: MI model were induced in Sprague-Dawley rats by left anterior descending coronary artery ligation. MI rats were respectively administrated T, S, G, TSG and CDF. Plasma was analyzed by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Partial least squares discriminate analysis (PLS-DA) models were built to evaluate the therapeutic and synergistic effects of TSG at whole level. 22 MI biomarkers in rat plasma were also investigated to explain that. Results: TSG brings nearly equal therapeutic effects on MI as CDF and it plays more stable regulated action on those 22 identified metabolites than single compound. Conclusions: Overall, there were few methods for the study of synergistic effects of Chinese medicine. Our results suggested that metabolomics offers a new idea for Chinese medicine research. [Copyright &y& Elsevier]

Background: Injection drug use (IDU) is one of the major modes of HIV transmission in China. Drug use is illegal in China, all identified drug users are registered by Public Security Bureau, and most were sent to detention; most detainees engaged in high risk behaviours. In order to well understand the HIV/AIDS knowledge among detainees, a survey was conducted in different detention settings in Hunan province in 2008 to assess knowledge and attitudes about HIV among detainees and to provide useful information for HIV prevention and intervention strategies in detention centers.Methods: A cross-sectional survey was conducted in 10 detentions in Hunan province, China, and demographic information along with knowledge and attitude of HIV/AIDS was collected through standardized interviews. Descriptive statistics were used to describe HIV knowledge, attitudes, and education services among detainees.Results: There were 956 detainees interviewed from 10 detention centers. The male to female ratio was 2.24:1. The majority detainees received nine years of compulsory education, accounting for 51.5%. There were nine questions to assess HIV/AIDS knowledge of detainees, and 35.7% of those surveyed answered all nine questions correctly. There were 92.3% (882/956) who consented to be informed about the HIV antibody test results when tested, and 81% (774/956) elected that their family members were also informed. All detention centers had an organized HIV/AIDS education program.Conclusion: This study gives us an overview about HIV/AIDS knowledge in detention in Hunan province, and all detention sites in the study provided HIV/AIDS intervention services among detainees that focused on HIV/AIDS knowledge, attitude, and health behaviors. [ABSTRACT FROM AUTHOR]

• Green leaf litter (GL) experienced a faster decay than senescence leaf litter (SL). • The temperature sensitivity (Q 10) of decomposition of GL was lower than that of SL. • The Q 10 of litter decomposition was negatively controlled by litter quality. • The faster litter decay after warm was due to reduced microbial carbon use efficiency. In the context of climate change, more frequent and severe extreme climate events are expected, which could lead to increased leaf fall before senescence. The decomposition of those abnormal fallen leaf litters may play a pivotal role in affecting the carbon (C) cycle in terrestrial ecosystems. Nevertheless, how their decomposition responds to temperature increase has rarely been studied, which limits the accurate estimation of the response of soil C dynamics to global warming and associated feedback. In the present study, green leaves (GL) were used to represent abnormal fallen leaf litters, and we compared the temperature sensitivity (Q 10) of the decomposition of GL with that of the corresponding senescent litters (SL) from nine species, which are widely distributed in subtropical China. Results showed that GL experienced a faster decomposition than SL. Conversely, the Q 10 of GL decomposition was significantly lower than that of SL decomposition. We also found that the Q 10 values of litter decomposition correlated positively with the C:N ratio and the lignin:N ratio, which supported the "C quality temperature" hypothesis. Furthermore, Q 10 was negatively controlled by phospholipid fatty acids of total microbes, fungi, and bacteria in soils. Experimental warming evidently increased the metabolic quotient of litter decomposition (q CO 2); a greater increase occurred in the decomposition of SL rather than that of GL. A positive correlation between Q 10 and warming-induced relative change in q CO 2 was also detected. We highlighted that the increasing inputs of abnormal fallen leaf litters caused by climate change could decrease the Q 10 of litter decomposition. [ABSTRACT FROM AUTHOR]

Frost damage of soil foundations of engineering structures is controlled by mechanical properties of soil under frozen and unfrozen states, existing widely in cold regions such as Genhe area that is termed as the "pole of cold" in China. For investigating engineering properties of soil in cold regions, a series of triaxial compressive tests were carried out on both frozen and unfrozen Genhe silty clay with different degrees of compaction under different confining pressures. The test results show that the stress-strain curves gradually change from softening to hardening with increasing confining pressure, temperature and decreasing compaction degree. Additionally, both axial and radial deformation is more sensitive to lower confining pressures. An accurate method was proposed for determining the elastic modulus. The elastic modulus and strength decrease significantly as the state of soil changes from frozen to unfrozen. The effect of compaction degree on radial deformation, strength and failure strain is gradually eliminated with the increase of confining pressure, which can be observed in both frozen and unfrozen soil. The isotropic tensile strength and the cohesion were obtained in the stress spaces of p - q and σ - τ respectively, and the ice cementing force was identified by adopting the difference of the two strength parameters between frozen state and unfrozen state. The results indicate that the ice cementing force calculated by two strength parameters is consistent, which increases with increasing compaction degree. • The coupling effect of compaction degree and confining pressure was identified. • A method was proposed for accurately determining the elastic modulus under global strain measurement. • The restraining effect of confining pressure on radial deformation was quantified. • The ice cementing force was determined by two methods and the two results were consistent. [ABSTRACT FROM AUTHOR]

Planted forests are a key component of sustainable forest management, as their fast-growing biomass can provide many important ecosystem goods and services essential to human well-being. Accurate estimation of forest biomass is important for global carbon accounting and afforestation policy making, yet saturated reflectance signals over vegetation and a shortage of cloud-free images during the growing season largely limit the utility of optical remote sensing for biomass estimation of planted forests in subtropical and tropical regions. Stand age is a crucial factor in determining forest growth and stand development but hasn't been widely used in remote sensing-based biomass estimation approaches. The main objective of this study was to investigate the applicability of an allometric analysis approach combined with Landsat-derived forest age structure to estimate stand biomass of fast-growing forest plantations in a subtropical landscape of China. We used the Vegetation Change Tracker (VCT) approach and Landsat time series data from 1986 to 2016 to detect annual stand-replacing disturbance and estimate forest stand age. Allometric equations and relative growth rate functions were combined to establish the linkage between tree biomass and forest stand age. We also modeled the spatial distribution of tree biomass using a conventional remote sensing (CRS) method that only utilizes spectral and textural variables and an extended CRS method that incorporates stand age (CRS_EX). We then compared the CRS and CRS_EX methods with the allometric analysis method to highlight the importance of stand age and post-disturbance forest regrowth for biomass estimation. The Landsat-derived disturbance history was significantly correlated with stand age (R2 = 0.82, RMSE = 3.7 year, p < 0.01). The CRS_EX and allometric analysis methods substantially improved tree biomass estimates (R2 CRS_EX = 0.77, RMSE CRS_EX = 37.7 t/ha; R2 Allometric = 0.70, RMSE Allometric = 43.5 t/ha) compared to the CRS method (R2 CRS = 0.53, RMSE CRS = 54.38 t/ha). Tree biomass estimated from the allometric analysis method aligned better with the allometric growth curves, while CRS_EX and CRS methods both exhibited notable overestimation for young and mid-aged forests. This study suggests that allometric models have the potential to be applied in subtropical forest plantations through the use of the existing forest stand development knowledge and increasingly open access remote sensing data. • Stand age of plantation forests can be hindcasted using dense time series of Landsat-derived disturbance history. • Spectral-only remote sensing approaches fail to capture biomass variations along the gradient of stand age. • Combining stand age and allometry theory can improve tree density and biomass estimations substantially. [ABSTRACT FROM AUTHOR]