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Benggang, an erosional phenomenon located in southern China, exhibits distinctive characteristics that can have profound ecological and agricultural consequences as well as pose risks to human life. Previous investigations have primarily focused on elucidating the relationships between the physical and chemical attributes of soils collected from Benggang. However, the precise role of free iron oxides in the surface properties of Benggang soil and its contribution to the formation of Benggang remains largely unexplored. In this study, we aim to investigate the role of free iron oxides in Benggang soil by removing them and subsequently introducing goethite to evaluate their impact on the soil’s surface properties. Our results reveal a decrease in the surface charge density of soil colloidal particles with increasing soil depth. Specifically, the uppermost red soil layer exhibits the highest value, followed by the sandy soil and the lowermost clastic layer. Upon removing free iron oxide, we documented reductions of 44.28% (red soil), 20.62% (sandy soil), and 8.70% (clastic layer) in the surface charge density of colloidal particles. The red soil layer presented an over 18-fold increase compared to the initial linear shrinkage, followed by the sandy soil and clastic layer. Notably, the addition of goethite to the iron oxide-free soil layers resulted in the recovery of approximately 81.93%, 121.13%, and 104.35% of the initial surface charge density, respectively. Moreover, significant changes in volume shrinkage were observed, with approximately 97.54% (red soil), 94.75% (sandy soil), and 89.72% (clastic layer) of the initial values being influenced. These findings underscore the substantial influence of free iron oxide on the physicochemical properties of Benggang soil and contribute to a comprehensive understanding of the erosive mechanisms underlying Benggang formation. [ABSTRACT FROM AUTHOR]

Coal and gas outburst is a type of coal mine dynamic disaster with complex causes and serious consequences. In China, the number and scale of outburst disasters are among the highest in the world. It is an inevitable stage for outburst that the mechanical instability of the combination of intact coal and tectonic coal (CICTC) in strata. The dip angle of the interface has an important influence on the instability of CICTC-containing gas. To further understand the instability process of CICTC, the uncoordinated deformation of CICTC was defined. According to this, three strain conditions were delimited. The variations of stress under three strain conditions were analyzed, the expressions of additional interfacial stress were established. Then, based on the Mohr–Coulomb criterion, the strength characteristics and failure forms were analyzed. It was found that the dip angle deflects the principal stress in the interface, and the influences of additional stresses on the value of principal stress are opposite. These two reasons make the principal stress state and instability process of the combination complicated. Finally, combined with actual parameters, the instability processes of CICTC under different stress paths and buried depths were studied. It can be found that the failures of CICTC under different stress paths were concentrated appearing in the tectonic coal body, intact coal interface, and tectonic coal interface. With the increase of buried depth, the initial maximum principal stress increases and the reduction from additional stresses to the strength of intact coal interface enhances, which makes the combination damage easily and the failure form change. The research results in this paper can provide a theoretical basis to prevent and control the outburst of the combination containing gas considering the dip angle of the interface. Highlights: The uncoordinated deformation of combination considering the dip angle was first defined. The expressions of additional interfacial stress of combination considering the dip angle were established The influences of different stress paths and buried depths for the instability of combination were discussed quantificationally. [ABSTRACT FROM AUTHOR]

Today, China has become the world's third largest international trading country and the largest container manufacturer. However, with the demand of industrial production, resulting in the decrease of tropical rain forest year by year, clonal wood (apitong) has become a rare tree species, and the raw materials used in the production of container wood flooring have gradually developed from imported clonal wood to multi-timber. In this case, it is very important to find new materials to replace imported clone wood and study the mechanism of damage (destruction) of container wood flooring subjected to external strength. Based on the mechanical analysis and comparison of 7 260 kg container wood floor test in trolley and conventional laboratory load test, the causes and cracking position of container wood floor opening were studied, and the form and mechanism of container wood floor under the action of external strength were clarified. [ABSTRACT FROM AUTHOR]

Fighting the COVID‐19 pandemic requires large numbers of citizens to adopt disease‐preventive practices. We contend that national identification can mobilize and motivate people to engage in preventive behaviors to protect the collective, which in return would heighten national identification further. To test these reciprocal links, we conducted studies in two countries with diverse national tactics toward curbing the pandemic: (1) a two‐wave longitudinal survey in China (Study 1, N = 1200), where a national goal to fight COVID‐19 was clearly set, and (2) a five‐wave longitudinal survey in the United States (Study 2, N = 1001), where the national leader, President Trump, rejected the severity of COVID‐19 in its early stage. Results revealed that national identification was associated with an increase in disease‐preventive behaviors in both countries in general. However, higher national identification was associated with greater trust in Trump's administration among politically conservative American participants, which then was associated with slower adoption of preventive behaviors. The reciprocal effect of disease‐preventive behaviors on national identification was observed only in China. Overall, our findings suggest that although national identification may serve as a protective factor in curbing the pandemic, this beneficial effect was reduced in some political contexts. HighlightsPolicymakers should note that national identity serves as a protective factor in curbing the COVID‐19 pandemic. Narratives that highlight the collective agency of people would be useful in promoting disease‐preventive actions as long as they are also endorsed by national leaders.National leaders should provide clear and consistent recommendations in promoting disease‐preventive actions.Practitioners and policymakers should be aware of how the communication strategies they use would be affected by society's political contexts. Mobilizing disease‐preventive actions through a patriotic frame might not be useful when national leaders did not unambiguously promote disease prevention. [ABSTRACT FROM AUTHOR]

Many COVID-19 conspiracy theories implicate China and its agents, whether implicitly or explicitly, as conspirators with potentially malicious intent behind the current pandemic. We set out to explore whether Chinese people believe in pandemic-related conspiracy theories, and if so, how do their secure (in-group identification) and defensive (collective narcissism) in-group positivity predict their conspiracy beliefs. We hypothesized that national identification would negatively predict the tendency to attribute responsibility to an in-group, thus predicting less risk-rejection conspiracy theory beliefs (e.g., COVID-19 is a hoax). In contrast, national collective narcissism would positively predict the tendency to attribute responsibility for the pandemic to an out-group, which in turn would validate conspiracy theories that acknowledge the risk of the pandemic (e.g., COVID-19 is a bioweapon). To test these predictions, we collected data in China (n = 1,200) in April 2020. Supporting our predictions, national identification was negatively associated with risk-rejection conspiracy beliefs via in-group attribution, whereas national collective narcissism was positively associated with risk-acceptance conspiracy beliefs via out-group attribution. [ABSTRACT FROM AUTHOR]

Panonychus citri (McGregor) is the most common pest in citrus-producing regions. Special low-toxicity acaricides, such as spirocyclic tetronic acids and mite growth inhibitors, have been used for a long time in China. However, pesticide resistance in mites is a growing problem due to the lack of new acaricide development. Wide-spectrum insecticides, such as amitraz have gained acceptance among fruit growers. An amitraz-resistant strain of P. citri was obtained by indoor screening to examine field resistance monitoring of mites to acaricides and to explore the resistant mechanism of mites against amitraz. The amitraz-resistant strain of P. citri had an LC50 value of 2361.45 mg l−1. The resistance ratio was 81.35 times higher in the resistant strain of P. citri compared with the sensitive strain. Crossing experiments between the sensitive and resistant strains of P. citri were conducted, resulting in a D value of 0.11 for F1 SS♀×RS♂ and 0.06 for F1 RS♀×SS♂. Reciprocal cross experiments showed that the dose–mortality curves for the F1 generations coincided, indicating that the resistance trait was not affected by cytoplasmic inheritance. The dose–expected response relationship was evaluated in the backcross generation and a significant difference was observed compared with the actual value. The above results indicate that the inheritance of resistance trait was incompletely dominant, governed by polygenes on the chromosome. Synergism studies demonstrated that cytochrome P450s and esterase may play important roles in the detoxification of amitraz. Based on differential gene analysis, 23 metabolism-related genes of P. citri were identified, consistent with the results of synergism studies. Real-time PCR verification implied that P450s, ABC transporters, and acetylcholinesterase might influence the detoxification of amitraz by P. citri. These results provide the genetic and molecular foundation for the management of pest mite resistance. [ABSTRACT FROM AUTHOR]

To examine the relationship between proactive personality and professional identity of undergraduate nursing students, including the role of psychological resilience and irrational belief as mediators. Personality has been shown to play a crucial role in determining professional identity. However, the influence of proactive personality on professional identity in the nursing field is poorly understood and requires further investigation. We conducted a cross-sectional study in China. Between July and December of 2021, 860 nursing undergraduates participated in an online questionnaire survey. Four main variables (proactive personality, psychological resilience, irrational belief and professional identity) and two covariates (willingness to choose nursing profession and family attitude towards nursing) were assessed. The assessment tools chosen are both valid and reliable. To test the proposed multi-mediation model, linear regression analysis by Hayes's SPSS macro-PROCESS was used. The results revealed that PP, PR and PI were positively connected with one another, but negatively with IB. PP positively predicted PI through direct and indirect paths, after controlling for two covariates. The percentage of indirect path (78.72%) outweighed the direct path (21.28%). The indirect effect of PR (72.51%) was higher than that of PR and IB (6.21%). PI was also positively predicted by students' "Yes" willingness and families' "supportive" attitude towards nursing. This study stated that nursing educators should take nursing students' PP seriously, which would allow for activities to be taken to improve their PR and decrease their IB, hence continuously enhancing their PI. In addition, respecting students' professional aspirations and improving family support may also be valuable ways to boost their PI. [ABSTRACT FROM AUTHOR]

Two new limonoids, kihadanin C (1) and 23-methoxydasylactone A (2), together with seven related known ones, 3 - 9, were isolated from the root bark of the plant Dictamnus dasycarpus. The structures of the new compounds were elucidated on the basis of extensive analyses of their spectroscopic data (1Dand 2D-NMR, MS) and by comparison of their NMR data with those reported in the literature. To the best of our knowledge, 1 presents the first example of A,D-seco limonoid with an unusual 3,4-dihydroxy- 2,5-dimethoxytetrahydrofuran moiety as ring E. In the bioassay in vitro, 7 showed moderate antibacterial activity against Staphylococcus aureus, while 8 and 9 displayed neuroprotective activities against H2O2-induced injury in SH-SY5Y cells. [ABSTRACT FROM AUTHOR]

Three fungi with different types of transformation of glycyrrhizin (GL) were isolated from the soil samples of glycyrrhiza glabra planting area in China. According to their morphologies and 18 S rDNA gene sequence analysis, the three fungi were identified and named as Penicillium purpurogenum Li-3, Aspergillus terreus Li-20 and Aspergillus ustus Li-62. Transforming products analysis by TLC and HPLC-MS indicated that P. purpurogenum Li-3, A. terreus Li-20 and A. ustus Li-62 could stably transform GL into GAMG, GAMG and GA, and GA, respectively. P. purpurogenum Li-3 was especially valuable to directly prepare GAMG for applications in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

In this paper the researchers collected 28 times of maximum light including 4 times of those observed at the Xinglong station, the National Astronomical Observation of China between May 27, 2004 and June 1, 2004 and 1 time of maximum light from a 60 cm telescope on May 4, 1984. It found that the O-C point distribution was more completely compared than in any papers published before. The period is decreasing at the rate of about (1.4±0.1)×10−8 per year, which should not be caused by stellar evolution. It might be only part of a binary orbital light-time variation or other unknown reason. The time scale is longer than Pocs and Szeidl’s suggestion; the star needs more observations before we can be certain of the exact light-time variation. [ABSTRACT FROM AUTHOR]

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.

Agricultural non-point source pollution is threatening water environmental health of the Three Gorges reservoir. However, current studies for precision management of the agricultural non-point source pollution within this area are still limited. The objective of this study was identifying the critical areas and primary sources of agricultural non-point source pollution for precision management. Firstly, the inventory analysis approach was used to estimate the discharge amount of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) from farmland fertilizer, crop residues, livestock breeding, and daily activities. Afterwards, the deviation standardization method was applied to evaluate the emission intensity of TN, TP, and COD, as well as calculating the comprehensive pollution index (CPI) of each village, based on which the critical areas for agricultural non-point source pollution management could be distinguished. Moreover, the equivalence pollution load method was conducted to identify the primary pollution sources within each critical zone. The above methods were implemented to an emigrant town within the Three Gorges reservoir area named Gufu. Results showed that agricultural non-point source pollution in Gufu town has been alleviated to a certain extent since 2016. Nevertheless, in four areas of the town (i.e., Longzhu, Fuzi, Shendu, and Maicang), the agricultural non-point source pollution still deserved attention and improvement. For the mentioned critical areas, farmland fertilizer and livestock breeding were the primary sources causing agricultural non-point source pollution. The emission amount of TN and TP from farmland fertilizer accounted for 60% and 48% of the total, respectively. And those from livestock breeding were 29% and 46%. Our research could provide definite targets to relieve agricultural non-point source pollution, which had great significance to protect water environment while coordinating regional economic growth after emigrant resettlement., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

We established 340-year chronologies of total ring width, early wood width, and late wood width with tree-ring samples of Pinus taiwanensis at high altitude collected from the western Tianmu Mountain in northern Zhejiang Province. According to the criterion that subsample signal strength (SSS) should be larger than 0.8, the reliable period was from 1810 to 2019. Through the correlation analysis between chronologies and climatic factors, we examined the responses of tree ring growth to climate. The results showed that radial growth of P. taiwanensis was more sensitive to temperature than to precipitation. Comprehensively considering the correlation analysis results for the raw and first-order difference series, early wood width was significantly correlated with the early growing season mean and maximum temperatures of the prior year, while late wood width with prior May and current September mean and maximum temperatures. The correlation pattern of total ring width was similar to that of early wood width, although at a low level. The optimal correlation was between early wood width and prior April-July mean temperature. Based on this relationship, April-July mean temperature of the Tianmu Mountain, East China was reconstructed for the period of 1809-2018 with an explained variance of 61.5%. Both the raw and first-order difference series passed the split sample calibration-verification test. The warm periods were 1809-1833 and 1965-2018, with a cold period in 1834-1964. Temperature had risen rapidly since the 1960s. From the standpoint of low frequency, it reached an unprecedented level since the 1980s over the past 210 years. Spatial correlation analysis showed that the reconstructed temperature series could represent temperature variations of East China, which had a good agreement with a reconstructed regional temperature series from East China. Our results showed that P. taiwanensis had a great potential for paleoclimate reconstruction in East China.

In order to investigate the hypolipidaemic and antioxidant effects of various dark teas produced from different post-fermentation using the same raw material, a hyperlipidaemia zebrafish model combined with binding bile salts assay and antioxidant assays were performed in this study. Results showed that the hypolipidaemic effect of dark tea extracts increased significantly (p < 0.05) while the antioxidant ability decreased sharply compared with raw material. Particularly, Liupao tea (50%) and Pu-erh tea (48%) showed promising hypolipidaemic potential; however, the antioxidant capacity of Pu-erh tea decreased (31-49%) most dramatically. Besides, the levels of total polyphenols and catechins decreased sharply, but theabrownin, gallic acid, and caffeine increased significantly after post-fermentation. Moreover, the potential mechanisms of regulating hyperlipidaemia by dark tea extracts were discussed. These results suggest that microbial fermentation significantly affects the bioactivity of dark teas, and provide theoretical basis for processing and improving of dark tea products for hyperlipidaemia therapy., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The growth, biomass, nutrient content and accumulation as well as the vertical distribution of nutrient accumulation in Cunninghamia lanceolata plantation across densities of 1800, 3000, 4500 trees·hm -2 were stu-died in order to provide scientific basis for efficient cultivation of C. lanceolata plantation. The total amounts of nutrients accumulated in C. lanceolata plantation with 1800, 3000, 4500 trees·hm -2 were 1311.57, 2531.55 and 2307.33 kg·hm -2 , respectively. There were significant variations among different densities. Under the same density, the order of nutrient content and accumulation in C. lanceolata plantation was total N > total K > total Ca > total Mg > total P. Moreover, the amount of nutrients in trunk and bark decreased with the increases of tree height. The amount of nutrient accumulation in persistent withered branch and leaf were allocated from middle to the upper part of tree, while the opposite was observed for fresh branch and leaf. N accumulation increased with the increases of stand densities, while the other nutrients first increased then decreased. The order of the amount of nutrient accumulation in trunk, bark, root, persistent withered branch, persistent withered leaf and litter among different densities was 4500 > 3000 > 1800 trees·hm -2 , and was 3000 > 1800 > 4500 trees·hm -2 in fresh branch and leaf, and 1800 > 3000 > 4500 trees·hm -2 in understory. Under the densities of 1800 and 4500 trees·hm -2 , the nutrient distribution ratio in bark was the largest, accounting for 21.6% and 19.4%. In 3000 trees·hm -2 , the distribution ratio of fresh leaves reached its maximum, accounting for about 22.9%, and the next was fresh branches, which had a distribution ratio of about 17.8%. 3000 trees·hm -2 was the most appropriate density for nutrient accumulation and distribution in C. lanceolata plantation.

To understand the effects of straw return modes on soil carbon pools, we investigated total soil organic carbon (SOC), labile organic carbon fractions, and inorganic carbon (SIC) in different straw return modes at a depth of 0-40 cm under a maize-wheat cropping system in the Guanzhong Plain, Shaanxi, based on an 11-year field experiment. There were five straw return modes, i.e ., no return of straw of both wheat and maize (CK), the retention of high wheat stubble plus the return of chopped maize straw (WH-MC), the return of both chopped wheat and maize straw (WC-MC), the retention of high wheat stubble and no return of maize straw (WH-MN), and the return of chopped wheat straw and no return of maize straw (WC-MN). The proportions of SOC storage were significantly higher under the WH-MC and WC-MC treatments than that under the CK by 28.1% and 22.2%, respectively. The proportions of SIC storage were increased by 20.4% and 17.3%, respectively. Compared with the initial value, the increases of sequestered SOC and SIC ranged from -0.84 t·hm -2 to 6.55 t·hm -2 , respectively, and from -0.26 t·hm -2 to 8.61 t·hm -2 , respectively. The efficiency of sequestration of SOC was 7.5%. To maintain the basic SOC level, the minimum carbon input from straw was 4.65 t·hm -2 ·a -1 . The contents of labile carbon fractions at the 0-20 cm layer increased significantly under the WH-MC and WC-MC treatments compared with those of the control. Results of principal component analysis showed that the changes in soil carbon pools were primarily affected by the amount of straw return. Additionally, the increases in SIC storage could be ascribed to the Ca 2+ and Mg 2+ ions derived from irrigation water and plant residues that could coprecipitate with the CO 2 from SOC mineralization to form CaCO 3 . In conclusion, our results indicated that the straw return mode that utilized the retention of high wheat stubble and chopped maize straw was sufficient to maintain soil carbon storage and would be the optimal straw-returning strategy for the region.

Pinellia ternata is a medicinal herb of Araceae, and its tubers are used as medicines. It is a common Chinese herbal medicine in China and has a large market demand. When exposing to strong light intensity and high temperature during the growth process, P. ternata withers in a phenomenon known as &quot;sprout tumble&quot;, which largely limits tuber production. Shade can effectively delay sprout tumble formation and increase its yield, however the relevant regulation mechanism is unclear. DNA methylation, as a self-modifying response to environmental changes, is often involved in the regulation of plant growth and development. In this study, P. ternata grown under natural light and 90% shading were selected as the control group and the experimental group for genomic DNA methylation analysis by using methylate sensitive amplification polymorphism(MSAP). The results showed that a total of 617 loci were detected with 20 pairs of primers, of which 311 were in the natural light group and 306 in the shading group. The methylation sites in the light and shading groups accounted for 58.2% and 71.57%, respectively, and the methylation ratios in the methylation sites were 27.65% and 29.41%, respectively, indicating that shading significantly induced the genome DNA methylation of P. ternata. Compared to the natural light group, shading promoted 32.51% of the genes methylation, while inducing 16.25% gene demethylation. This study reveals the DNA methylation variation of P. ternata under shading conditions, which lays a preliminary theoretical foundation for further analysis of the mechanism of shading regulation of P. ternata growth from epigenetic level.

Given the importance of undergrowth vegetation to plantation ecosystem, this study analyzed the effects of three kinds of understory management measures, including understory preservation, understory removal, and interplanting, on the soil bacterial diversity, community structure and relative abundance under large diameter timber plantation of Cunninghamia lanceolata using high-throughput sequencing technology. The relationship between soil physical and chemical properties and bacterial community diversity were analyzed. The results showed that Chao1, Ace and Shannon indices of soil bacterial communities of understory preservation were higher than those of understory removal and interplanting. Actinobacteria, Acidobacteria and Chloroflexi were the dominant bacteria groups in the soil of C. lanceolata plantation. Compared with understory removal and interplanting, the relative abundance of Proteobacteria, Planctomycetes, Firmicutes and Verrucomicrobia in the soil of understory preservation was relatively high, while that of Actinobacteria, Acidobacteria and Chloroflexi was relatively low. There were significant differences in the relative abundance of Firmicutes, Planctomycetes, Verrucomicrobia, Parcubacteria and Actinobacteria among three understory management measures. The contents of moisture, total nitrogen, total phosphorus, hydrolyzed nitrogen and available phosphorus in the soil were important factors affecting soil bacterial community structure. Soil bacterial diversity indices had significant positive correlation with the contents of total nitrogen, total phosphorus, total potassium, hydrolyzed nitrogen and available potassium in the soil.

A field experiment was conducted in the Key Field Station for Monitoring of Eco-Environment of Purple Soil of the Ministry of Agriculture of China in the farm of Southwest University in Chongqing. Static opaque chamber and gas chromatography methods were used to study the effect of plastic film mulching on CH 4 and N 2 O emissions characteristics from a rice-rapeseed crop rotation in situ for one year. The results showed that CH 4 and N 2 O emissions are mainly concentrated in the early stages of the growth of each crop and there is a clear seasonal variation of CH 4 emissions during the rice growing period and N 2 O in the rapeseed growing period. The CH 4 flux changed from -0.45 to 1.90 mg·(m 2 ·h) -1 and the N 2 O flux varied between -46.1 and 2040.7 μg·(m 2 ·h) -1 over the entire year. Plastic film mulching was found to increase the total emissions of CH 4 and N 2 O, with the total CH 4 emission of(27.22±4.48) kg·hm -2 over the entire year, which is 26.22% higher than that of the non-mulching treatment(19.93±0.56) kg·hm -2 . The total amount of N 2 O emissions under film mulching treatment increased 16.6% from (11.27±2.77) kg·hm -2 under no mulching treatment to (13.14±0.82) kg·hm -2 . The results analyzed for soil moisture and soil temperature showed that mulching significantly increased the soil moisture during the rapeseed season, while there was no obvious correlation with soil temperature (at depths of 5 cm and for the surface temperature) for each crop season. During the rapeseed growing season, CH 4 and N 2 O emissions negatively correlated with soil moisture and has a significant negative correlation during the seedling period with film mulching treatment. Moreover, under the two treatments, the correlation between CH 4 and N 2 O emissions and soil temperature was negligible. This study indicates that plastic film mulching impacts CH 4 and N 2 O emissions at different growth stages of the crops, which changes the proportion of the emission of the two gases over the whole growth period, and promotes the emission of CH 4 and N 2 O in the rice-rapeseed system. In the time scale of 100 years, the integrated global warming potentials (GWP) of CH 4 and N 2 O emission under plastic film was a CO 2 equivalent of 4213.00 kg·hm -2 compared with that under conventional treatment of 3454.17 kg·hm -2 . Conventional emits 22.0% less CO 2 , indicating that plastic film mulching is not an effective measure for carbon sequestration.

Pistacia chinensis is a strict dioecious plant with male and female flowers in individuals. In China, P. chinensis is widely planted for biodiesel oil due to high oil content in seeds. In practice it requires to grow more female plants for biodiesel production. At present, there are still no reliable methods for sex determination during the long juvenile stage of this species. In order to develop protein molecular markers for sex determination in P. chinensis, proteomic approach was used to identify differentially expressed proteins between male and female plants. Vegetative organs (leaf and stem) rather than reproductive organs/tissues were used for protein extraction so as to develop protein markers which can be used in siblings before flowering. Protein was extracted using a phenol-based protocol. By using two-dimensional electrophoresis, a total of 10 protein spots were found to be differentially expressed in leaf and stem between both sexes, of which 7 were successfully identified by mass spectrometry and matched to 6 functional proteins such as NB-ARC domain containing protein, light harvesting chlorophyll a/b binding protein, asorbate peroxidase (APX), eukaryotic translation initiation factor 5A2, temperature-induced lipocalin (TIL) and phosphoglycerate kinase (PGK). The sex-related difference displayed in a tissue-specific way, especially in stem. PGK existed in high abundance in stem phloem in the female, but was almost not detected in the male; APX and two TIL species were highly abundant in the stem of male plants, while their abundance was much lower in female plants. Moreover, these abundance differences were further confirmed in individual plants. Hence, it is assumed that APX, PGK and TIL might be promising candidates to serve as protein molecular markers for sex determination in P. chinensis. Our results form the basis for a further understanding of the biochemical mechanisms of sex determination in P. chinensis.

Objective: To examine the mortality and risk factors among HIV-infected patients during 1989 - 2011 in Dehong prefecture, Yunnan province., Methods: All HIV-infected patients reported during 1989 - 2011 in Dehong prefecture who held local residency were included in the study. Mortality rates and cumulative survival rates were calculated. Multiple regression analysis under Cox proportional hazard model was conducted to examine the risk factors for deaths., Results: A total of 13 006 HIV-infected patients were included in this study including 73.2% males, 79.1% peasants and 48.7% married at the time of reporting. 64.5% of the patients were ethnic minorities, and 68.7% were illiterate or having received only primary school education. All the patients were followed-up for a total of 55 962.30 person-years with 4648 patients died, with overall mortality rate as 8.31/100 person-years. The mortality rate had been increasing from 1990 to 2004 but decreasing since 2005. The average survival time since the identification of HIV infection was 9.48 years overall, and was 16.65 years for those having received antiretroviral treatment (ART) and 7.67 years for those without ART. Data from multiple regression analysis indicated that ART and socio-demographic characteristics such as age, gender, ethnicity, occupation, marital status, education background etc. were significantly associated with death among HIV-infected patients., Conclusion: The comprehensive AIDS campaigns including ART had significantly reduced the deaths among HIV-infected patients in Dehong prefecture. More efforts on the scaling up program of ART as well as the enhanced management and follow-up program tailored for HIV-infected patients with different socio-demographic characteristics were needed to further reduce the deaths in the area.

Objective: To explore the determinants and changes of CD4(+) T cell counts among antiretroviral treatment-naive HIV/AIDS patients in Dehong prefecture, Yunnan province., Methods: A retrospective cohort analysis was conducted on HIV-infected local residents, being reported during 1989 through May 2010, in Dehong prefecture. The patients had received at least two CD4(+) T cell counting tests before receiving the antiretroviral treatment (ART). Difference between the first and the last CD4(+) T cell counts was calculated and described. Logistic regression analysis was conducted to examine the determinants of significant depletion of CD4(+) T cell counts among them., Results: A total of 4487 HIV/AIDS patients were included in the study. The change of CD4(+) T cell counts between the first and the last CD4(+) T cell count tests had a median of -2.0 cells/µl in month (IQR: -8.2 - 3.6) and was significantly associated with socio-demographic characteristics, HIV transmission mode, the first or baseline CD4(+) T cell counts and the time interval between the first and the last CD4(+) T cell counting tests etc. About 60.0% (2693/4487) of the HIV/AIDS patients had deletions of CD4(+) T cell counts, and 31.2% (1400/4487) had significant (≥ 30%) deletions of CD4(+) T cell counts. Results from the multiple logistic regression analysis indicated that age, ethnicity, marital status, HIV transmission mode, the first CD4(+) T cell counts and the interval between the first and the last CD4(+) T cell counting tests were significantly associated with the significant depletion of CD4(+) T cell counts., Conclusion: The changing rate of CD4(+) T cell count among ART-naive local HIV-infected patients in Dehong prefecture, Yunnan province was relatively slow. However, substantial proportion of them showed significant decreases of CD4(+) T cell counts, which was determined by many factors. More efforts were needed to systematically and consistently follow-up those HIV-infected patients and measure their CD4(+) T cell counts in China, in order to instantaneously monitor the disease progression, and the initiation of ART, if necessary.

Objectives: To analyze the fatality and causes of death related to comprehensive prevention and care programs among HIV-infected patients in Dehong prefecture of Yunnan province, from 1989 to 2010., Methods: Data on HIV/AIDS death cases in Dehong prefecture were extracted from the "Chinese National Comprehensive HIV/AIDS Prevention and Care Information System" and were analyzed., Results: From 1989 to the end of 2010, a total of 13 493 HIV/AIDS cases registered as local residents or currently living in Dehong, had been reported. Among them, 8569 were reported as HIV cases with 2036 deaths and the other 4924 were reported as AIDS cases with 2251 deaths. A few of the cases had survived for 15 - 20 years. By the end of 2010, the number of deaths was higher than the number of survivors among HIV/AIDS cases reported before 2004, whereas the number of survivors was higher than the number of deaths among HIV/AIDS cases reported in 2004 and there after. During the twenty years' period, the proportion of reported HIV/AIDS cases died in the same year showed a secular trend of being low-highest-low, rising up to > 10.0% in 2001, peaking at 18.9% in 2003 and then continuously going down to 5.8% in 2010. The proportion of HIV/AIDS cases who survived at the beginning but died later in the year was going down since 2007. The proportion of HIV/AIDS deaths died directly from AIDS was increasing whereas the proportion of HIV/AIDS deaths dying directly from overuse of drugs was decreasing in the recent years. Among HIV/AIDS deaths, the proportion of ever received CD4(+) T-cell testing and the proportion of ever having received antiretroviral treatment were also increasing in the past years, reaching to 89.9% and 25.5% in 2010, respectively., Conclusion: The case fatality of HIV/AIDS was decreasing in the past years in Dehong prefecture. More efforts were needed to scale up the CD4(+) T-cell count testing and antiretroviral treatment in order to further reduce both morbidity and mortality among HIV/AIDS patients in Dehong prefecture. It is critical to improve surveillance program on HIV/AIDS deaths in the rural areas.

Objective: To determine the adherence to and its determinants of methadone maintenance treatment (MMT) among heroin addicts in Dehong prefecture in Yunnan province from 2005 to 2009., Methods: A dynamic cohort analysis was conducted with the time of treatment initiation as the time of cohort entry, to calculate the proportion of adhering to the treatment at different time points after initiation of the treatment, and to study the determinants of adherence., Results: A total of 3758 had been treated. Among them, 95.8% were males, 75.8% aged between 20 - 39 years, 90.4% were peasants or unemployed, 57.0% were ethnic minorities, 35.0% were single and 55.5% were married with spouses, 43.9% were illiterate or educated at most primary school. The age of first using drugs averaged at 23.93 years. About 96.3% of the study subjects had used heroin and 21.7% were HIV-infected. The minimum time under MMT was less than 1 month and the maximum 61 months. The median methadone dose at first delivery was 25 ml, with the minimum 1 ml and the maximum 330 ml. By the end of the study or observation period, a total of 1798 patients had withdrawn from treatment and 1960 were still under treatment. The proportions of adherence to or still being under the treatment after 1, 3, 6, 9, 12, 24, 36, 48 and 60 months treatment were 0.919, 0.847, 0.756, 0.690, 0.637, 0.519, 0.417, 0.360 and 0.321, respectively. Multiple regression analysis using Cox proportional hazard model indicated that withdraw from the methadone maintenance treatment was significantly associated with location of the treatment clinics, year of treatment initiation, marital status, HIV infection status, methadone dose of first delivery and the result of last urine test for heroin use., Conclusion: MMT attendants in Dehong prefecture had a relatively high withdraw rate and low adherence rate. More efforts are needed to provide tailored counseling and education to MMT attendants, to provide family and community support, appropriate methadone dose at first delivery, and to better coordinate with local police department.

Objective: To understand the relationship of tendency on drug abuse and related influencing factors for middle school students., Methods: A total of 603 students were assessed with self-made copying style scale, consciousness to resistance of smoking, drinking and resistance ability through a questionnaire. A relationship model was set up by structure equation modeling., Results: Copying style and resistance ability had significantly direct influence on tendency of drug abuse (with standardized coefficients were 0.202 and 0.092 respectively). Consciousness to resistance of smoking and drinking had significantly indirect influence on tendency of drug abuse. The goodness of fit for the structural equation model was satisfactory, with GFI, AGFI, RMSEA as 0.981, 0.972 and 0.014 respectively., Conclusion: It was meaningful to grasp some copying skills and resistance ability to lower the tendency of drug abuse in middle school students.

Objective: To study multiple risk factors of N-nitroso compounds (NOC) in high- and low-risk areas for esophageal cancer in southern China., Method: The samples of 24-hr diets and 12-hr overnight urine were collected from 120 male healthy subjects (35-64 years old) selected by a 3-stage random cluster sample procedure in each of the high-risk area (Nanao County) and low-risk area (Lufeng County) for esophageal cancer. The urinary samples were respectively collected from undosed subjects, subjects ingested 500 mg L-proline (together with 200 mg ascorbic acid ) and subjects ingested 500 mg proline. The levels of total NOC (TNOC), N-nitrosamino acids (NAAs), volatile N-nitroso compounds and reductive ascorbic acid (VC) in the samples were measured. By unconditional logistic stepwise regression model, we analyzed the association between the multiple factors of NOC and esophageal cancer mortality. The factors included the intake and excretion levels of various kinds of NOC, the ability of NAAs endogenous formation and its inhibition by VC, and nutrition status of VC in the body., Results: The results of unconditional logistic stepwise regression showed that risk factors entered the model were diet TNOC content (OR 9.613, 95% CI 1.921-48.115) and urinary NAAs level after ingested VC (OR 1.137, 95 % CI 1.001-1.298)., Conclusion: The higher level of diet TNOC and the lower inhibition ability of NOC endogenous formation by VC were important risk factors on NOC etiology of esophageal cancer in southern China.

Objective: To study the dynamic change of the ingredients of Coptis chinensis and evaluate the quality of the crude drugs from main producing areas., Method: The ingredients of samples from Shizhu and Wuxi counties in Chongqing, Hongya and Dayi counties in Sichuan, Zhenping county in Shanxi, Lichuan county in Hubei were analyzed for berberine, coptisine, jatrorrhizine, palmatine and the total alkaloids by HPLC and UV methods., Result and Conclusion: The contents of measured indexes were mostly highest in 5-years-old C. chinensis. Considering factors such as the yield, it is reasonable to harvest the 5-years-old C. chinensis. There are minor differences in condents of C. chinensis from different areas, all tested samples met the pharmacopoeial standards. It is concluded that the general quality of C. chinensis was good and acceptable.