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In order to investigate the relationship between 137Cs and soil total carbon (TC) in artificial forests, a study was conducted on Platycladus orientalis forest (PO), Quercus variabilis forest (QV), and abandoned land slope. Results demonstrated that both PO and QV have higher levels of 137Cs and lower TC stocks compared to the abandoned land slope. There is a significant correlation between 137Cs and TC in artificial forests, suggesting that 137Cs can be used as a reliable tracer for TC migration in afforestation areas. However, it is not recommended to use 137Cs for estimating TC in abandoned land slopes. [ABSTRACT FROM AUTHOR]

Shrub encroachment is very common in the semiarid regions of China. However, surprisingly little research has been conducted to evaluate the effects of shrubs on soil properties in these regions compared with other regions in the world. Three sites, one without shrub (state 1), one with 13% shrub coverage (state 2), and the third one with 40% shrub coverage (state 3) in the semiarid Inner Mongolian grasslands were selected to investigate the effects of the shrub Caragana microphylla Lam on soil properties. Soil samples were collected from three sites to evaluate the changes of bulk density (BD), grain size distribution, aggregate stability, soil organic carbon (SOC), total nitrogen (TN), and soil water content (SWC) with the development of shrub encroachment. The results showed that BD and soil sand declined, and silt, aggregate >2 mm and the mean weight diameter (MWD) rose from state 1 to state 3, especially in 20–60 cm depths. With the shrub encroachment, the content of SOC and TN increased, and especially, the increase trends were more obvious in the deeper soil than in the surface soil. SWC increased with the development of shrub encroachment at 20–60 cm depths. Greater and deeper water infiltration existed after heavy rainfall in states 2 and 3, suggesting that macropore flow appeared in shrub encroachment sites. All these results indicated that shrub encroachment improved soil physicochemical properties, particularly in deep soil. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore Internet addiction (IA) and its associated factors among Chinese adolescents. Ten thousand one hundred fifty-eight Chinese adolescents were selected in this study by using random cluster sampling. The prevalence rate of IA among Chinese adolescents was 10.4%. Multivariate logistic regression analyses showed gender, the only child, father-adolescent relationship, annual family income, academic performance, physical exercise, Rosenberg Self-esteem Scale (RSES) score, and Liebowitz Social Anxiety Scale (LSAS) score were significantly associated with IA among adolescents in social anxiety group (P < 0.05). In addition, gender, parental control, annual family income, academic performance, physical exercise, RSES score, and LSAS score were significantly associated with Internet addiction among adolescents in non-social anxiety group (P < 0.05). The mediating effects of social anxiety between multiple factors and IA were also significant. These findings can provide guidance aimed at reducing IA among Chinese adolescents. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to test the hypothesis that depression mediated the association between stressful life events and Internet addiction. The participants were randomly recruited from 5 vocational schools in Anhui Province, China and completed a succession of self-completed questionnaires including the Young Internet Addiction Test, the Adolescent Self-rating Life Events Checklist, and the Zung Self-Rating Depression Scale. A structural equation model was applied to examine the mediating role of depression in the association between stressful life events and Internet addiction. The frequency and severity of stressful life events was higher in the Internet addiction group than that in the average Internet use group. Participants in the Internet addiction group experienced more depression when compared to average Internet users. Significant and positive correlations between stressful life events, depression and Internet addiction were detected. The standardized path coefficients from life events to depression and from depression to Internet addiction were significant. The path from life events to internet addiction was also significant. The findings suggested that life events associated with Internet addiction both directly and indirectly, depression mediated the association between life events and Internet addiction. [ABSTRACT FROM AUTHOR]

A cross-sectional study design was applied amongst a random sample (n = 10158) of Chinese adolescents. Self-completed questionnaires, including demographic characteristics, Internet use situation, Youth Internet Addiction Test, Youth Social Support Rating Scale and Zung Self-rating Depression Scale were utilized to examine the study objectives. Among the study population, the prevalence rate of Internet addiction was 10.4%, with 1038 (10.2%) moderately and 21 (0.2%) severely addicted to the Internet. Results from the multivariate logistic regression analyses suggested that a variety of related factors have significant effects on Internet addiction (parental control, per capita annual household income, academic performance, the access to Internet, online activities). The correlation coefficients showed that Internet addiction was negatively correlated with social support and positively associated with depression. Social support had a significant negative predictive effect on Internet addiction. The mediating effect of depression between social support and Internet addiction was remarkable. [ABSTRACT FROM AUTHOR]

Background: Suicide is the leading cause of death among 15–34 year olds in China, but no national data are available on the suicide and suicide attempts rates of college students, a sub-group of youth with 23 million. Several studies have reported the prevalence of suicide attempts among college students, however, no meta-analysis pooling the prevalence of suicide attempts is found. Objective and Methods: This study aims to estimate the pooled prevalence of suicide attempts among college students in China. The relevant studies up to August 2014 were systematically searched via electronic databases (PubMed-Medline, Embase, Chinese Wanfang database, Chinese National Knowledge Infrastructure and Chinese VIP database). We only selected original articles that either reported the prevalence of suicide attempts or sufficient data for calculating the prevalence. Results: A total of 29 eligible studies, with 88,225 college students, were finally included. The maximum and minimum reported prevalences of suicide attempts among college students in China were 0.4% and 10.5%, respectively. The pooled prevalence of suicide attempts was 2.8% (95%CI: 2.3%–3.3%). Subgroup analyses showed that the pooled estimate of prevalence of life time suicide attempts was 2.7% (95%CI: 2.1%–3.3%), and 12-month suicide attempts was 2.9% (95%CI: 2.0%–3.8%). The prevalence for males was 2.4% (95%CI: 1.8%–3.0%), and for females was 2.7% (95%CI: 1.9%–3.7%). The prevalences among college students in grade 1 through 4 were 2.8% (95%CI: 1.7%–3.8%), 1.8% (95%CI: 1.2%–2.3%), 2.0% (95%CI: 0.8%–3.1%), and 2.9% (95%CI: 0.1%–6.7%), respectively. The prevalences among college students from rural and urban areas were 5.1% (95%CI: 2.8%–7.5%) and 3.7% (95%CI: 1.4%–5.9%), respectively. Conclusions: 2.8% prevalence of suicide attempts and more than 600,000 suicide attempters among college students indicate that suicide attempt among college students is an important public health problem in China. More attention should be paid to the current situation. [ABSTRACT FROM AUTHOR]

MAN5, the main extracellular saccharide hydrolase from Bacillus sp. MSJ-5, is an endo-β-mannanase with a demand of at least five sugar moieties for effective cleavage. It has a pH optimum of 5.5 and a temperature optimum of 50°C and is stable at pH 5–9 or below 65°C. MAN5 has a very high ability to hydrolyze konjac flour, 10 U/mg of which could completely liquefy konjac flour gum in 10 min at 50°C. HPLC analysis showed that most glucomannan in the konjac flour was hydrolyzed into a large amount of oligosaccharides with DP of 2–6 and a very small amount of monosaccharide. With the culture supernatant as enzyme source, the optimum condition to prepare oligosaccharides from konjac flour was obtained as 10 mg/ml konjac flour incubated with 10 U/mg enzyme at 50°C for 24 h. With this condition, more than 90% polysaccharides in the konjac flour solution were hydrolyzed into oligosaccharides and a little monosaccharide (2.98% of the oligosaccharides). Konjac flour is an underutilized agricultural material with low commercial value in China. With MAN5, konjac flour can be utilized to generate high value-added oligosaccharides. The high effectiveness and cheapness of this technique indicates its potential in industry. [ABSTRACT FROM AUTHOR]

The Grain for Green Program (GGP) initiated by Chinese government significantly impacts mitigating environmental degradation. Soil water resources probably constrain large-scale vegetation restoration projects in arid and semi-arid regions. Characterizing soil water dynamics after the GGP's implementation is essential in assessing whether vegetation restoration can be sustained as part of ecological restoration. In this study, four sites were selected for field investigation: original natural grassland (NG) and grassland that was reconverted from cropland 12 years (12-year site), 8 years (8-year site), and 6 years (6-year site) before. Soil water at five depths was measured continuously at 10 min intervals at four sites. The findings showed that less rainfall infiltrated a deeper soil layer as the time after restoration augmented, and the 12-year site had the shallowest infiltration depth and soil water storage. Younger restored grassland (8-year and 6-year sites) had a higher soil water content than older restored grassland (12-year site) and NG. The soil water content decreased steadily with restoration age after an immediate initial rise, and the highest soil moisture was in the 8-year site. The results suggest that soil water dynamics varied with GGP and a soil water deficit could be formed after the GGP's implementation for 12 years in semi-arid grassland. [ABSTRACT FROM AUTHOR]

Harmful red tides in China have caused paralytic shellfish toxins (PSTs) pollution and led to severe socioeconomic effects in shellfish aquaculture. Although shellfish can survive harmful algal blooms, the effects on their Condition Index (CI) have been underestimated. This study sought to evaluate the effects of the profiles and levels of paralytic shellfish toxins on variations in the CI in bivalves under natural blooming conditions. We observed clear soft tissue lesions to varying degrees except in Mytilus galloprovincialis after toxin exposure. Among the five species of shellfish exposed in situ, only M. galloprovincialis accumulated PSTs content above the maximum permitted level (800 μg STX di-HCl eq./kg). The highest toxin content in all sample tissues was observed in Patinopecten yessoensis. Significant interspecies differences in PSTs accumulation among the five bivalve species were observed in the hepatopancreas. A total of nine PSTs components and four new C-11 hydroxyl metabolites (so-called M-toxins) toxins were detected, and detoxification diversity was observed among bivalves. We observed a higher proportion of M-toxin in early stages, and the proportions changed only slightly over time in M. galloprovincialis and Magallana gigas , thus accounting for the significantly higher metabolism rate. Notably, the CI in M. gigas and Argopecten irradians was positively correlated with lowest toxin accumulation of PSTs content, but significantly inhibited. In conclusion, our results revealed a significant inhibitory effect on the CI in shellfish, in a species specific manner, with distinct levels of inhibition correlated with different toxin metabolites. Our study revealed the toxin content of different bivalves exposed to a natural red tide environment and the consequent effects on growth, thus building a foundation for research on the mechanisms underlying the effects of PSTs on growth. These data establish the ecological and economic significance of the effects of harmful algal blooms on bivalves. [Display omitted] • The diversity in the PST accumulation capacity of bivalves was observed in situ. • PSTs negatively affected the CI values in distinct levels. • P. yessoensis had the most rapid PST accumulation and clearance rates. • The CI values of mussels showed an S-shaped correlation with toxin distribution. • Metabolite M-toxins were estimated, to expand on prior work. [ABSTRACT FROM AUTHOR]

Abstract: Many arid grasslands around the world are affected by shrub encroachment. However, the transition states of shrub-encroached ecosystems are still poorly known, and the effects of human disturbances are difficult to quantify during the transition process. This study investigated plant biomass, community characteristics, and water capturing capability of the shrub and interspace grass patches during the different transition states of Caragana microphylla Lam-encroached grassland in response to the intensity of anthropogenic disturbances. The results indicate that the number of plant species increased with the disturbance intensity at the shrub patches and that the total aboveground biomass (AB) significantly decreased from the slightly disturbed site to the moderately disturbed site, then significantly increased from the moderately disturbed site to the seriously disturbed site. The total belowground biomass (BB) was much greater in the shrub patches than the interspace grass patches at the above three sites. The results also suggest that grass or shrub dominance were alternative stable states in the processes of shrub encroachment but that a threshold existed during state transition. Dye tracing experiments showed that shrubs had higher water capturing capability than grass. The shrubs could capture and transport water to the deeper soil layers in the shrub patches. We speculate that the competitive advantage for biomass and water by shrubs could be reversed for grass if the disturbance intensity does not exceed a threshold value. A continual increase of anthropogenic disturbance would further lower the water capturing capability of grasses, leading to an increase of biomass and the size of shrub patches and a shift in the landscape to a shrub-dominated state, which would be irreversible. [Copyright &y& Elsevier]

The small genera Allaeanthus and Malaisia within the Moraceae have important edible, medicinal, and economic value. However, complete plastome blueprints and a well-resolved evolutionary history of these two genera are still lack, thereby limiting their conservation and application. The recent discovery of a new distribution of Allaeanthus kurzii in Hainan, China, marked by the collection of two unique samples, alongside three samples of Malaisia scandens, has opened new avenues for research. This study aimed to compare the Allaeanthus and Malaisia plastomes of Hainan Province samples with those of samples from other regions, focusing on plastome structure, codon usage bias, natural selection, and the evolutionary history of A. kurzii and M. scandens. The results showed that both species had a quadripartite plastome structure, with sizes ranging from 162,134 to 162,170 bp for A. kurzii and 161,235 to 162,134 bp for M. scandens. Both species displayed loss of the infA gene and reduction of the rpl22 gene. Two highly variable regions (petD-trnD-GUC and rpl20-clpP) and three highly variable genes (rpl20, petB, and rpl16) were identified in A. kurzii, while two highly variable regions (ycf2-ndhB and ccsA-ndhE) and three highly variable genes (psbT, rpl36, and ycf2) were found in M. scandens. The protein-coding sequences (CDSs) of the Allaeanthus and Malaisia plastomes exhibited similar patterns of adaptive indices and codon usage frequencies. The genes associated with photosynthesis underwent strong purifying selection. Phylogenetic analysis revealed that Allaeanthus, Broussonetia, and Malaisia constituted a monophyletic group, with Malaisia being more closely related to Broussonetia. Broussonetia diversified approximately 19.78 million years ago, Malaisia approximately 4.74 million years ago, and Allaeanthus approximately 16.18 million years ago. These new plastome-based discoveries will guide conservation planners and medicinal plant breeders and genetic resource development for these species in the region., (© 2024. The Author(s).)

As an important ecological barrier for the North China Plain, research on the spatial variations of soil nutrients in the southern foot of the Taihang Mountains is of great significance for the forestry ecological construction in this rocky mountainous area. With the typical slopes (the artificial forestland and the natural wild slope) of the southern foot of the Taihang Mountains as the research objects, we used the grid method to arrange sampling points, and combined classical statistics, geostatistics and constrained sorting methods to analyze the spatial variations of soil nutrients. The results showed that: 1) soil total carbon (TC) contents were 6.80-57.05 g·kg -1 , and the total nitrogen (TN) contents were 0.74-3.93 g·kg -1 . The coefficients of variation of both soil TC and TN were 25.0%-52.8%, belonging to the moderate degree of variation, which were caused by the combination of random and structural factors. The spatial aggregation of soil nutrients decreased with increasing lag distances. 2) The contents of soil nutrients had increasing trends from the top to the bottom of the slopes, with high nutrient values appearing at the bottom of the slopes. 3) The soil bulk density, gravel content, vegetation coverage, and soil water content were the main factors affecting the spatial variability of soil TC and TN on the southern foot of the Taihang Mountains. 4) Soil water content was the main factor affecting soil nutrients at the natural wild slope, but not at the artificial forestland.

Accurate spatial distribution information of soil properties would be helpful for improving the accuracy of soil organic carbon storage estimation. In this study, terrain factors were used as predictors, and the fuzzy C-means (FCM) clustering method was used to make digital soil prediction mapping for soil organic carbon content, soil bulk density, soil depth, and soil gravel content in Nanshan forest farm in Jiyuan City of Henan Province. Based on the digital mapping results, the prediction mapping of soil organic carbon density and the estimation of soil organic carbon storage were realized. The results showed that the average soil organic carbon density in the study area based on the digital soil mapping method was 4.24 kg·m -2 , the mean error (ME), mean absolute error (MAE) and root mean square error (RMSE) of the prediction map were 0.08, 2.80 and 5.03 kg·m -2 , respectively. The accuracy, stability and reliability of the prediction results were higher than the tradiation methods. The soil organic carbon storage in the study area was estimated to be 3.08×10 8 kg. Based on the digital soil mapping technology, only a small number of soil samples could be used to map and estimate the soil organic carbon density with high accuracy, which could characterize the spatial distribution characteristics of soil organic carbon density. This study provided a new way to estimate soil organic carbon storage, which would help to improve the accuracy and efficiency of soil organic carbon storage estimation.

Objective: This study aimed to examine the developmental pattern of diurnal cortisol rhythm during pubertal transition and its prospective association with psychopathological symptoms., Methods: A cohort of 1158 children consisting of 608 boys and 550 girls aged 7 to 9 years (mean [standard deviation] age = 8.04 [0.61] years) were recruited in the Anhui Province of China in 2015 (wave 1). A single awakening sample was collected at baseline, and three additional samples were collected at one weekday in wave 2 to wave 4. Four indices of cortisol activity were evaluated and calculated across the day: awakening cortisol level, cortisol awakening response, the area under the curve with respect to ground (AUC), and the diurnal cortisol slope. In each wave, pubertal development was assessed by testicular size in boys and Tanner scales in girls. Psychopathological symptoms were ascertained in waves 2 to 4., Results: Multilevel mixed models revealed no significant pubertal changes in diurnal cortisol activity in girls. In boys, awakening cortisol (β = -0.005, p = .004) and total cortisol output (lnAUC, β = -0.005, p = .040) significantly decreased across pubertal transition. Higher awakening cortisol and total cortisol output (lnAUC) were associated with higher scores on internalizing symptoms in girls (β = 0.82, p < .001; β = 0.62, p = .012) and externalizing symptoms in boys (β = 0.73, p = .001; β = 0.55, p = .019) during the 3-year follow-up. In contrast, no associations were found between cortisol awakening response and diurnal cortisol slope with psychopathological symptom scores in boys or girls., Conclusions: Development of diurnal cortisol activity during pubertal transition occurs in a sex-specific manner. Awakening cortisol level and daily total cortisol output may serve as markers for psychopathology during pubertal transition.

Objectives: The different etiology of HF has different prognostic risk factors. Prognosis assessment of ICM and NICM has important clinical value. This study is aimed to explore the predicting factors for ICM and NICM., Methods: 1082 HFrEF patients were retrospectively enrolled from Jan. 01, 2016 to Dec. 31, 2017. On Jan. 31, 2019, 873 patients were enrolled for analysis excluding incomplete, unfollowed, and unexplained data. The patients were divided into ischemic and non-ischemic group. The differences in clinical characteristics and long-term prognosis between the two groups were analyzed, and multivariate Cox analysis was used to predict the respective all-cause mortality, SCD and rehospitalization of CHF., Results: 873 patients aged 64(53,73) were divided into two groups: ICM (403, 46.16%) and NICM. At the end, 203 died (111 in ICM, 54.68%), of whom 87 had SCD (53 in ICM, 60.92%) and 269 had rehospitalization for HF(134 in ICM, 49.81%). Independent risk factors affecting all-cause mortality in ICM: DM, previous hospitalization of HF, age, eGFR, LVEF; for SCD: PVB, eGFR, Hb, revascularization; for readmission of HF: low T3 syndrome, PVB, DM, previous hospitalization of HF, eGFR. Otherwise; factors affecting all-cause mortality in NICM: NYHA III-IV, paroxysmal AF/AFL, previous hospitalization of HF, β-blocker; for SCD: low T3 syndrome, PVB, nitrates, sodium, β-blocker; for rehospitalization of HF: paroxysmal AF/AFL, previous admission of HF, LVEF., Conclusions: Both all-cause mortality and SCD in ICM is higher than that in NICM. Different etiologies of CHF have different risk factors affecting the prognosis., Competing Interests: Conflicts of interest There is no conflict of interest., (Copyright © 2020. Published by Elsevier B.V.)

Background: Pervious studies suggested occupational workers exposure to pentachlorophenol (PCP) might contribute to increased risk of cancer. However, few studies have focused on associations between PCP and cancer risk at the community level., Objective: The present study was to explore the cancer risk for the community population living long-term in a PCP contaminated area., Methods: All the cancer cases diagnosed in 2009- 2011 in Tongling City were collected. The cancer patients' residencies were geo-referenced in each district. The historical PCP usage for each district of Tongling was calculated as the PCP pollution index, which was further used to divide into PCP exposure categories. Standardized rate ratios (SRRs) of cancer incidence were applied to detect the cancer risk as exposure grade elevated. Correlation analysis was performed to analyze the relationship between PCP pollution and cancer incidence., Results: A total of 5,288 cancer cases (3,451 male and 1,837 female) were identified. PCP usage was correlated with the incidence of leukemia (r=0.88, P=0.002) for males, and with cancer of the esophagus for males (r=0.83, P=0.008) and females (r=0.71, P=0.020). Compared with the low exposure category, significant SRRs for total cancer sites was obtained for high PCP exposure category (SRR=1.61, 95%CI=1.59-1.62). Most SRR values of the cancer sites were significantly increased as exposure grade elevated and exposure time extended., Conclusion: The present study found that community residents living in the PCP contaminated area had increased risk of cancers. Leukemias, lymphomas and nasopharyngeal and esophageal cancers are most possibly associated with PCP exposure.

Objective: To examine the association between internet addiction and suicidal behaviors in adolescence and to explore whether the association could be partly or fully accounted by depression or/and behaviors related to the impulsivity., Methods: A total of 3507 urban adolescent students in Hefei were administered to complete the questionnaire concerning interact addiction disorder (IAD), suicidal behaviors during the 12 months preceding the survey, behaviors related to the impulsivity, Center for Epidemiologic Studies Depression Scale and early childhood adversities, respectively. Hierarchical logistic regressions were used to evaluate the associations and possible roles of depression and behaviors related to the impulsivity between internet addition and suicidal behaviors after adjustment for confounding factors., Results: Of the 3507 participants, 5.2% were diagnosed as IAD, 27.4% reported suicidal ideation during the 12 months preceding the survey, with another 9.5% had a plan and 2.6% had an attempt. Internet addition was associated with suicidal ideation (OR = 1.79, 95%CI: 1.32 - 2.44), plan (OR = 2.32, 95%CI: 1.57 - 3.42), and attempt (OR = 2.08, 95%CI: 1.03 - 4.22). After adjustment for potential confounding factors, the association between internet addition and attempt was insignificant. When depression and behaviors related to the impulsivity were entered into Hierarchical regression respectively, the associations between internet addition, suicidal ideation and plan were substantially reduced. While internet addition was enter into Hierarchical regression, the associations between depression, behaviors related to the impulsivity, suicidal ideation and plan were not reduced., Conclusion: Adolescent internet addition seems to be associated with suicidal ideation and plan, and the association is possibly mediated by depression and behaviors related to the impulsivity.

Objective: To study the prevalence and its related factors on breast-diseases among women at reproductive age in the rural areas of Anhui province, and to provide data for the development of prevention and healthcare on breast-diseases., Methods: 54 400 rural fertile women aged 15 - 49 were surveyed by a stratified-cluster-random sampling method. Breast examination was conducted in two steps: converging at the clinics, and later visiting their households. Clinical examination and X-ray scanning check up were performed., Results: The rate of the breast-disease among the rural fertile women was 10.69%, and the first three breast-diseases were galactophore hyperplasia, fibroadenoma and intracanalicular papilloma, their prevalence were 9.39%, 0.65% and 0.50% respectively. The results of logistic regression showed in comparison with women and their husbands who were under 29, low education, husbands being farmers, medium menstrual flow, no dysmenorrheal, the total number of deliveries was 0 while no history of abortion, those who aged 30 to 44, high education, husbands were doing other jobs (they were mainly businessmen or teachers), more menstrual flow, dysmenorrheal, the total number of deliveries was 1, they were more likely to got breast diseases. However in comparison with women who earned less than 5000 Yuan per year, those who had 5001 to 8000 Yuan per year were less likely to get breast diseases., Conclusion: Breast diseases were prevalent among rural fertile women and were affected by multi-factors. We suggested that screening program on breast cancer should be carried out at regular intervals and at the same time, to intensify second-class prevention of breast cancer, together with actively treating patients with galactophore hyperplasia, to reduce the prevalence of precancerous pathological changes.