Functional abdominal pain disorders in children in southern Anhui Province, China are related to academic stress rather than academic performance.

BACKGROUND: Functional abdominal pain disorders (FAPDs) are one of the most common gastrointestinal disorders in children. The aim of this study was to investigate the prevalence of FAPDs in children in southern Anhui Province, China and their association with academic stress. METHODS: In this cross-sectional survey, we randomly selected children aged 6-17 years from 11 public schools in southern Anhui Province. FAPDs were diagnosed according to the Rome IV criteria, and a custom-designed questionnaire was used to investigate the association between academic stress and FAPDs in children. RESULTS: A total of 2,344 children aged 6-17 years were enrolled. The mean age was 12.4 ± 3.0 years. Of these children, 335 (14.3%) were diagnosed with FAPDs according to the Rome IV criteria. Among the children with FAPDs, 156 (46.6%) were boys, and 179 (53.4%) were girls. The prevalence was higher in girls than in boys. The most common disorder was irritable bowel syndrome (IBS) (n = 182 (7.8%)). Other types of FAPDs included functional abdominal pain-not otherwise specified (FAPNOS) (n = 70 (3.0%)), functional dyspepsia (FD) (n = 55 (2.3%)), and abdominal migraine (AM) (n = 28 (1.2%)). Academic stress, not meeting parental expectations, poor relationships with parents, and sleep disturbances were independent risk factors for FAPDs in children; academic performance was not associated with the development of FAPDs. CONCLUSION: There was a high prevalence of FAPDs among children in southern Anhui Province, China, and IBS was the most common subtype of functional abdominal pain. Academic stress, rather than academic performance, was associated with FAPDs in children.

Heavy metals in water and surface sediments of the Fenghe River Basin, China: assessment and source analysis.

This paper combines environmental science, inorganic chemistry, water quality monitoring and other disciplines to analyze and assess the heavy metals in the water bodies and sediments of the Fenghe River Basin (FRB) in Shaanxi Province, and reveal their sources. The Water Quality Index (WQI), Nemero Index (Pn), Geological Accumulation Index (I-geo) and Potential Ecological Risk Index (RI) are used to assess heavy metals in water and sediments. Pearson correlation analysis (CA), hierarchical cluster analysis (HCA), principal component analysis (PCA) and positive matrix factorization (PMF) models are used to study the relationship and source of heavy metals. The results show that most of the residual heavy metals in the water are below the corresponding environmental quality standards for surface water. Most of the heavy metals in the sediment exceed the background value of the soil. The factors or sources of heavy metals in water and sediment are revealed in detail through PMF models. The main sources of pollution in the region are urban construction and transportation, the electronics industry, machinery manufacturing and tourism. In water, the average contribution rates of these four sources to heavy metals were 36.8%, 11.7%, 9.4% and 42.0%, and in sediments were 8.0%, 29.2%, 23.9% and 38.9%. Therefore, these sectors should be given sufficient attention.

Control and remediation methods for eutrophic lakes in the past 30 years.

Accelerated eutrophication, which is harmful and difficult to repair, is one of the most obvious and pervasive water pollution problems in the world. In the past three decades, the management of eutrophication has undergone a transformation from simple directed algal killing, reducing endogenous nutrient concentration to multiple technologies for the restoration of lake ecosystems. This article describes the development and revolution of three remediation methods in application, namely physical, chemical, and biological methods, and it outlines their possible improvements and future directions. Physical and chemical methods have obvious and quick effects to purify water in the short term and are more suitable for small-scale lakes. However, these two methods cannot fundamentally solve the eutrophic water phenomenon due to costly and incomplete removal results. Without a sound treatment system, the chemical method easily produces secondary pollution and residues and is usually used for emergency situations. The biological method is cost-effective and sustainable, but needs a long-term period. A combination of these three management techniques can be used to synthesize short-term and long-term management strategies that control current cyanobacterial blooms and restore the ecosystem. In addition, the development and application of new technologies, such as big data and machine learning, are promising approaches.

Efficiency of Neuromuscular Electrical Stimulation and Transcutaneous Nerve Stimulation on Hemiplegic Shoulder Pain: A Randomized Controlled Trial.

OBJECTIVE: To compare the efficacy of neuromuscular electrical stimulation (NMES) and transcutaneous nerve stimulation (TENS) on hemiplegic shoulder pain (HSP). DESIGN: This is a prospective randomized controlled trial. SETTING: A rehabilitation hospital. PARTICIPANTS: Participants (N=90) were randomized into NMES (n=36), TENS (n=36), or control groups (n=18). INTERVENTIONS: NMES (15Hz, pulse width 200µs) was applied to supraspinatus and deltoids (medial and posterior parts), whereas TENS (100Hz, pulse width 100µs) was used on the same areas. The surface electrodes were placed near the motor points of the supraspinatus and medial or posterior bundle of deltoids. The 4-week treatment consisted of 20 sessions, each session composed of 1 hour of stimulation per day. Routine rehabilitation program without any stimulation was administered to the control and the NMES/TENS groups. Numerical rating scale (NRS), active/passive range of motion (AROM/PROM) of shoulder, upper extremity Fugl-Meyer Assessment (FMA), modified Ashworth scale (MAS), Barthel Index (BI), and stroke-specific quality of life scale (SSQOLS) were assessed in a blinded manner at baseline, 2, 4, and 8 weeks after treatment, respectively. MAIN OUTCOME MEASURES: The primary endpoint was the improvement from baseline in NRS for HSP at 4 weeks. RESULTS: NRS scores in NMES, TENS, and control groups had decreased by 2.03, 1.44, and 0.61 points, respectively after 4 weeks of treatment, with statistically significant differences among the 3 groups (P<.001). The efficacy of the NMES group was significantly better than that of the TENS group (P=.043). Moreover, the efficacy of NMES and TENS groups was superior to that of the control group (P<.001, P=.044, respectively). The differences in the therapeutic efficacy on shoulder AROM/PROM, FMA, MAS, BI, and SSQOLS scores were not significant among the 3 groups. CONCLUSIONS: TENS and NMES can effectively improve HSP, the efficacy of NMES being distinctly superior to that of TENS in maintaining long-term analgesia. However, NMES was not more efficacious than the TENS or control group in improving the shoulder joint mobility, upper limb function, spasticity, the ability of daily life activity, and stroke-specific quality of life in HSP patients.

Preparation of ureido-functionalized PVA/silica mesoporous fibre membranes via electrospinning for adsorption of Pb2+ and Cu2+ in wastewater.

Ureido-functionalized mesoporous polyvinyl alcohol/silica composite nanofibre membranes were prepared by electrospinning technology and their application for removal of Pb2+ and Cu2+ from wastewater was discussed. The characteristics of the membranes were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption analysis. Results show that the membranes have long fibrous shapes and worm-like mesoporous micromorphologies. Fourier transform infrared spectroscopy confirmed the membranes were successfully functionalized with ureido groups. Pb2+ and Cu2+ adsorption behavior on the membranes followed a pseudo-second-order nonlinear kinetic model with approximately 30 minutes to equilibrium. Pb2+ adsorption was modelled using a Langmuir isotherm model with maximum adsorption capacity of 26.96 mg g-1. However, Cu2+ adsorption was well described by a Freundlich isotherm model with poor adsorption potential due to the tendency to form chelating complexes with several ureido groups. Notably, the membranes were easily regenerated through acid treatment, and maintained adsorption capacity of 91.87% after five regeneration cycles, showing potential for applications in controlling heavy metals-related pollution and metals reuse.

Magnetic metal-organic frameworks: γ-Fe2O3@MOFs via confined in situ pyrolysis method for drug delivery.

A general one-step in situ pyrolysis route for the construction of metal-organic frameworks encapsulating superparamagnetic γ-Fe2O3NPs dispersed in the confined cavities of MOFs homogeneously is described. The integration of γ-Fe2O3 NPs or clusters into MOFs can endow these porous materials with superparamagnetic element. By the combination of the thermal stability of MOFs and pyrolysis of metal triacetylacetonate complex at matched conditions, the porous structure of MOFs are well maintained while the size-induced superparamagnetic property of nano γ-Fe2O3 is obtained. As a proof of concept, both the γ- Fe2O3@ZIF-8 and γ-Fe2O3@MIL-53(Al) were successfully prepared, and the latter was chosen to demonstrate its potential drug delivery as a magnetic MOF.

Global systematical and comprehensive overview of mountainous flood risk under climate change and human activities.

Snow-covered mountainous regions are crucial for the hydrologic cycle. Any changes in the cryosphere are critical and directly impact the hydrologic cycle and socio-environment of the downstream. It is likely to occur more extreme events of precipitations, raising the risk of flooding worldwide. Glacier melting is increasing, thus the formation of the moraine-dammed lake called glacial lake, whose outburst may be a catastrophic disaster. Due to steep topography, flash floods with high energy can sweep away infrastructure, electric power stations, property, and livelihood and even change the channel morphology, hence the whole environment. In this article, we present the causes of flooding in mountainous regions and historical trends of mountainous flooding and its management policies. Carbon emission is a driver to increase the temperature of the globe and which is triggering the flash floods in mountainous regions is illustrated using data from different sources. The discussion section includes how technology helps to achieve a climate-resilient environment. Understanding river morphology, mapping and monitoring risks, and simulating essential natural processes are necessary for reducing the cascading hazards in the mountains. There is still a gap in modern data collection techniques in mountainous regions. More advanced technology for regional and global collaborations, climate change adaption, and public awareness can build the climate resilience cryosphere.

Effectiveness of smartphone-assisted cardiac rehabilitation: a systematic review and meta-analysis.

PURPOSE: To explore the effectiveness of smartphone-assisted home cardiac rehabilitation and whether it can be used as a remote detection method to promote home cardiac rehabilitation. METHODS: Four databases were searched to collect randomized controlled trials (RCTs) about smartphone-assisted cardiac rehabilitation. The Cochrane risk-of-bias tool was used to assess the methodological quality of the included studies. Two independent investigators performed the literature screening, information extraction, and risk of bias assessment. Any disagreements were resolved by a third investigator. Meta-analysis and systematic review were performed. Sensitivity analysis and subgroup analysis were carried out to explore the sources of heterogeneity. RESULTS: A total of 14 RCTs involving 1962 patients were included. Meta-analysis showed that compared with conventional cardiac rehabilitation/usual care, smartphone-assisted cardiac rehabilitation significantly improved VO2peak in patients with cardiovascular disease (WMD= 1.32, 95%CI:0.82 to 1.81, p > 0.05) and enhanced their treatment compliance (RR = 1.62, 95%CI:1.21 to 2.17, p > 0.05). There were no significant differences in six-minute walk distance (WMD = 12.88, 95%CI:-0.82 to 26.57, p > 0.05), body mass index (BMI) (WMD=-0.14, 95%CI:-0.34 to 0.06, p > 0.05), life quality, psychological status, and other cardiovascular risks. CONCLUSION: Smartphone-assisted cardiac rehabilitation showed significant improvement in exercise capacity and treatment compliance in patients with cardiac rehabilitation but did not improve BMI, quality of life, psychological status, or reduce other cardiovascular risks. Smartphone-based cardiac rehabilitation is increasingly used as a remote detection method for cardiac rehabilitation in middle-income countries, which provides new insights into home cardiac rehabilitation.

Smartphone-assisted cardiac rehabilitation showed significant improvement in exercise capacity and treatment compliance in patients with cardiac rehabilitation.Smartphone-assisted cardiac rehabilitation showed no significant improvements in body mass index, quality of life, psychological status, and other cardiovascular risk.Smartphone-based cardiac rehabilitation is increasingly used as a remote detection method for cardiac rehabilitation in middle-income countries, which provides new insights into home cardiac rehabilitation.

Regio- and Stereoselective Organocatalyzed Relay Glycosylations To Synthesize 2-Amino-2-deoxy-1,3-dithioglycosides.

Herein, we describe a novel methodology for the regio- and stereoselective convergent synthesis of 2-amino-2-deoxy-dithioglycosides via one-pot relay glycosylation of 3-O-acetyl-2-nitroglucal donors. This unique organo-catalysis relay glycosylation features excellent site- and stereoselectivity, good to excellent yields, mild reaction conditions, and broad substrate scope. 2-Amino-2-deoxy-glucosides/mannosides bearing 1,3-dithio-linkages were efficiently obtained from 3-O-acetyl-2-nitroglucal donors in both stepwise and one-pot glycosylation protocols. The dithiolated O-antigen of E. coli serogroup 64 was successfully synthesized using this newly developed method.

A case report of phacolytic glaucoma in lens cortex behind posterior capsule: A CARE-compliant article.

RATIONALE: Phacolytic glaucoma (PLG), a secondary open-angle glaucoma caused by high molecular weight proteins leaking through the capsule of a hypermature cataract. Leakage of liquefied lens cortex behind the posterior capsule is rare. In this paper, we review a case of phacolytic glaucoma in the lens cortex behind posterior capsule. PATIENT CONCERNS: This case report describes a 79-year-old male patient with a 7-year history of progressive blurred vision and a 1-day history of distended in his left eye. He underwent phacoemulsification combined with intraocular lens implantation at our facility 7 years ago. DIAGNOSES: The patient had lower vision (light perception vision) and increased intraocular pressure (IOP) (60 mmHg) in the left eye. Auxiliary inspection found that the left eye had deep anterior chamber depth (around 1 corneal thickness of the peripheral AC angle) as well as vitreous and aqueous humor opacity in the left eye. Combining the clinical symptoms and examinations, we made the diagnosis of PLG in the left eye. INTERVENTIONS: The patient underwent trabeculectomy and extracapsular cataract extraction of the left after a stable ocular condition, during the operation to see that white chyous cortex was visible under the posterior capsule and posterior capsule membrane of the lens was avulsed circularly. OUTCOMES: The postoperative condition was stable. During the follow up of 3 months, the IOP of the left eye was stable without ocular discomfort. LESSONS: This case reported a patient with phacolytic glaucoma in the lens cortex behind posterior capsule who underwent successful surgery, indicating spontaneous capsule rupture can occur in the posterior capsules in PLG and when this situation is detected during the operation, the posterior capsule tearing method can be applied to absorb the lens cortex sticking at the posterior surface of the posterior capsule.

The role of long noncoding RNAs in therapeutic resistance in cervical cancer.

Cervical cancer is one of the common tumors and often causes cancer-related death in women. Chemotherapy is a common cancer therapy, which displays a pivotal clinical benefit for cancer patients. However, chemoresistance becomes a big obstacle for failure of treatment in cancer patients. Recently, long noncoding RNAs (lncRNAs) have been identified to regulate drug resistance in human cancers, including cervical cancer. In this review, we describe the role of lncRNAs in regulation of chemotherapeutic resistance in cervical cancer. We also discuss the molecular mechanisms of lncRNA-mediated drug resistance in cervical cancer. Moreover, we describe that targeting lncRNAs could reverse drug resistance in cervical cancer. Therefore, lncRNAs could become effective therapeutic targets and chemotherapeutic sensitizers for cervical cancer patients.

Pentagalloylglucose suppresses the growth and migration of human nasopharyngeal cancer cells via the GSK3ß/ß-catenin pathway in vitro and in vivo.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a type of malignant squamous cell tumour originating from the nasopharynx epithelium. Pentagalloylglucose (PGG) is a natural polyphenolic compound that exerts anticancer effects in many types of tumours. However, the role and underlying mechanism of PGG in NPC cells have not been fully defined. PURPOSE: This study aimed to investigate the anticancer activity of PGG as well as the potential mechanism in NPC cells. METHODS: The effects of PGG on the proliferation, apoptosis and cell cycle distribution of CNE1 and CNE2 cells were assessed by MTT and flow cytometry assays. Cell migration was evaluated using wound healing and transwell assays. The expression of microtubule-associated protein 1 light chain 3 beta (LC3B) was observed by immunofluorescence staining. Western blotting was used to explore the levels of related proteins and signalling pathway components. Furthermore, the effects of PGG on NPC cell growth were analysed in a xenograft mouse model in vivo using cisplatin as a positive control. RESULTS: PGG dose-dependently inhibited the proliferation of CNE1 and CNE2 cells. PGG regulated the cell cycle by altering p53, cyclin D1, CDK2, and cyclin E1 protein levels. PGG induced apoptosis and autophagy in NPC cells and elevated the Bax/Bcl-2 ratio and the protein levels of LC3B. Moreover, PGG decreased NPC cell migration by increasing E-cadherin and decreasing N-cadherin, vimentin and CD44 protein levels. Mechanistically, PGG treatment downregulated p-mTOR and ß-catenin expression but upregulated p-p38 MAPK and p-GSK3ß expression. In addition, PGG significantly inhibited NPC cell tumour growth and lung metastasis in vivo. CONCLUSION: PGG may suppress cell proliferation, induce apoptosis and autophagy, and decrease the metastatic capacity of NPC cells through the p38 MAPK/mTOR and Wnt/ß-catenin pathways. The present study provides evidence for PGG as a potential therapy for NPC.

Exploring sustainable solutions for the water environment in Chinese and Southeast Asian cities.

Water is essential for human activities and economic development, and the water environment significantly influences ecological balance and global climate. China and Southeast Asia are the most populous areas in the world, and their water resources are deteriorating day by day. We focus on five representative cities such as, Beijing, Jakarta, Hanoi, Kathmandu and Manila to investigate water-environmental problems with the ultimate goal of providing recommendations for sustainable urban water management. The study found that (1) the water environment of all cities has been polluted to varying levels, while the pollution has improved in Beijing and Jakarta, and the situation in other regions is severe. (2) The aquatic biodiversity has reduced, and its pollution is mainly caused by organic pollutants and decreasing river flow. In addition, numerous people live in megacities without access to clean surface water or piped drinking water, which greatly increases the use of groundwater. Further, frequent floods in the world leads to serious damage to urban infrastructure and further deterioration of water environment quality. To address these problems, countries and organizations have begun to construct wastewater treatment plants and develop water-saving technology to ensure healthy and sustainable development of water environment. The results and practical recommendations of this study can provide scientific insights for future research and management strategies to address water quality challenges during ongoing policy debates and decision-making processes.

Light-driven selective aerobic oxidation of (iso)quinoliniums and related heterocycles.

Selective C1-H/C4-H carbonylation of N-methylene iminium salts, catalyzed by visible-light photoredox and oxygen in the air, has been reported. A ruthenium complex acts as a chemical switch to conduct two different reaction pathways and to afford two different kinds of products. In the absence of the ruthenium complex, the Csp2-H bonds adjacent to the nitrogen atoms are oxidized to α-lactams by the N-methyleneiminium substrates themselves as photosensitizers. In the presence of the ruthenium complex, the oxidation reaction site of quinoliniums is switched to the C4 region, resulting in the formation of 4-quinolones. The use of two transformations directly introduces oxygen into the nitrogen heterocyclic skeletons under an air atmosphere.

Airborne phthalates in indoor environment: Partition state and influential built environmental conditions.

Exposure to phthalates has recently become a major public health concern. The information of indoor airborne phthalates and their air-particle partition in real indoor environmental condition is still limited. In this study, the gas- and PM2.5-concentrations of 7 phthalates in 40 residences were concurrently measured in summer and winter. The major phthalates (median concentration in the summer and winter, respectively) in indoor air were DMP (2442.3 and 2403.4 ng/m3), DiBP (801.0 and 640.0 ng/m3) and DnBP (5173.2 and 1379.6 ng/m3), whereas the major phthalates in PM2.5 were DiBP (1055.1 and 585.9 ng/m3) and DnBP (1658.5 and 1517.0 ng/m3) and DEHP (215.1 and 344.9 ng/m3). Air-PM2.5 partition coefficients (Kp) of DiBP, DnBP and DEHP were calculated: the summer and winter median values (m3/µg) were 0.053 and 0.011 for DiBP, 0.010 and 0.004 for DnBP, 0.021 and 0.025 for DEHP, respectively. Air-PM2.5 partition of DiBP and DnBP approached equilibrium, while that of DEHP did not reach equilibrium in either season. The impacts of built environmental conditions on phthalate concentrations were characterized. Elevated temperature resulted in accumulation of airborne phthalates. Higher air humidity led to more water absorption of aerosols in summer, facilitated mass transfer of phthalates from air to PM2.5, and resulted in greater Kp of DiBP and DnBP in the summer. Any factors such as proximity to local traffic highway and indoor smoking activities, which can increase indoor PM2.5 concentrations, resulted in significantly higher airborne phthalate concentrations. Improving ventilation was not an effective measure to reduce indoor airborne phthalate concentrations.

Anti-inflammatory activity of isobutylamides from zanthoxylum nitidum var. tomentosum.

Inflammation is a very common and important basic pathological process. There is still a great need for the isolation of effective anti-inflammatory agents from plants. In this paper, five new isobutylamides, zanthoxylumamides E-I (1-5), and four known isobutylamides (6-9) were isolated from Zanthoxylum nitidum var. tomentosum (Rutaceae). Chiral resolution of seven racemic isobutylamides (1-4 and 6-8) was successfully performed, and the absolute configurations of two stereoisomers of 1-4 were validated by ECD and NMR. The obtained isobutylamides were evaluated in vitro anti-inflammatory activity with the lipopolysaccharide (LPS)-stimulated production of nitric oxide (NO) in murine macrophage RAW264.7 cells. Compound 8 exhibited significant inhibition of LPS-induced NO production. The underlying molecular mechanisms of the anti-inflammatory activity of 8 revealed that it suppressed the NO production through the modulation of myeloid differentiation factor 88 (MyD88) and interferon regulatory factor 3 (IRF3) signaling pathways.

Water quality trend assessment in Jakarta: A rapidly growing Asian megacity.

Megacities are facing serious water pollution problems due to urbanization, rapid population growth and economic development. Water is an essential resource for human activities and socio-economic development and water quality in urban settings has important implications for human and environmental health. Urbanization and lack of sewerage has left the water in Jakarta, Indonesia in a heavily polluted condition. Rigorous assessment of urban water quality is necessary to understand the factors controlling water quality conditions. We use trend analysis to assess the current water quality conditions in Jakarta, focusing on Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), and Total Suspended Solids (TSS). In most monitoring stations analyzed, BOD and TSS concentrations have decreased over time, but from large starting concentrations. DO in most monitoring stations has increased. Although Jakarta's water quality has shown some improvement, it remains heavily impaired. The average value of BOD is low in upper stream stations compared to middle and lower stream stations. BOD and TSS trends of some water quality stations in middle and lower streams show increasing trends. Cluster analysis results suggest three groups for BOD and TSS, and four groups for DO. Understanding water quality conditions and factors that control water quality suggest strategies for improving water quality given current trends in climate, population growth and urban development. Results from this study suggest research directions and management strategies to address water quality challenges.

Synthesis and discovery of asiatic acid based 1,2,3-triazole derivatives as antitumor agents blocking NF-κB activation and cell migration.

A series of asiatic acid (AA) based 1,2,3-triazole derivatives were designed, synthesized and subjected to a cell-based NF-κB inhibition screening assay. Among the tested compounds, compound 6k displayed impressive NF-κB inhibitory activity with an IC50 value in the low micromolar range. A molecular docking study was performed to reveal key interactions between 6k and NF-κB in which the 1,2,3-triazole moiety and the hydroxyl groups of the AA skeleton were important for improving the inhibitory activity. Subsequently, surface plasmon resonance analysis validated the high affinity between compound 6k and NF-κB protein with an equilibrium dissociation constant (KD) value of 0.36 µM. Further studies showed that compound 6k observably inhibited the NF-κB DNA binding, nuclear translocation and IκBα phosphorylation. Moreover, in vitro antitumor activity screening showed that compound 6k (IC50 = 2.67 ± 0.06 µM) exhibited the best anticancer activity against A549 cells, at least partly, by inhibition of the activity of NF-κB. Additionally, the treatment of A549 cells with compound 6k resulted in apoptosis induction potency and in vitro cell migration inhibition. Thus, we conclude that AA based 1,2,3-triazole derivatives may be potential NF-κB inhibitors with the ability to induce apoptosis and suppress cell migration.

Impact of forest maintenance on water shortages: Hydrologic modeling and effects of climate change.

The importance of water quantity for domestic and industrial water supply, agriculture, and the economy more broadly has led to the development of many water quantity assessment methods. In this study, surface flow and soil water in the forested upper reaches of the Yoshino River are compared using a distributed hydrological model with Forest Maintenance Module under two scenarios; before and after forest maintenance. We also examine the impact of forest maintenance on these variables during extreme droughts. Results show that surface flow and soil water increased after forest maintenance. In addition, projections of future water resources were estimated using a hydrological model and the output from a 20km mesh Global Climate Model (GCM20). River discharge for the near-future (2015-2039) is similar to that of the present (1979-2003). Estimated river discharge for the future (2075-2099) was found to be substantially more extreme than in the current period, with 12m3/s higher peak discharge in August and 7m3/s lower in July compared to the discharges of the present period. Soil water for the future is estimated to be lower than for the present and near future in May. The methods discussed in this study can be applied in other regions and the results help elucidate the impact of forests and climate change on water resources.

Toxic effects of NH4+-N on embryonic development of Bufo gargarizans and Rana chensinensis.

Although nitrogen fertilizer is commonly used worldwide, little information is currently available about NH4+-N toxicity on amphibians. This study determined the acute and chronic toxic effects of NH4+-N on two native Chinese amphibian species (Bufo gargarizans and Rana chensinensis), and compared the negative sensitivity of different embryos to NH4+-N. Static renewal aqueous exposures were performed using B. gargarizans and R. chensinensis embryos at Gosner stage 2 over 96 h. In terms of 96 h-LC50, B. gargarizans and R. chensinensis embryos had significantly different responses to NH4+-N, and the latter was more sensitive to NH4+-N than the former. In the chronic toxicity test, exposure to 10 mg L-1NH4+-N or higher significantly decreased the hatching rate of embryos in both species. Significant increases in the abnormality rate of embryos at 50 mg L-1NH4+-N or higher were observed and morphological abnormalities were characterized by axial flexures, yolk sac edema, and hyperplasia in both species. Additionally, the total length of embryos decreased in a dose-dependent manner after exposure to NH4+-N. The results indicate that NH4+-N exposure can increase abnormality and inhibit the hatching and development of embryos in B. gargarizans and R. chensinensis.