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Abstract: A field experiment located in Taihu Lake Basin of China was conducted, by application of urea or a mixture of urea with manure, to elucidate the interception of nitrogen (N) export in a typical rice field through “zero-drainage water management” combined with sound irrigation, rainfall forecasting and field drying. N concentrations in floodwater rapidly declined before the first event of field drying after three split fertilizations, and subsequently tended to return to the background level. Before the first field drying, total particulate nitrogen (TPN) was the predominant N form in floodwater of plots with no N input, dissolved inorganic nitrogen (DIN) on plots that received urea only, and dissolved organic nitrogen (DON) on plots treated with the mixture of urea and manure. Thereafter TPN became the major form. No N export was found from the rice field, but total nitrogen (TN) of 15.8 kg/hm2 was remained, mainly due to soil N sorption. The results recommended the zero-drainage water management for full-scale areas for minimizing N export. [Copyright &y& Elsevier]

Domestic biodegradable wastes (DBW) pose a threat to environmental quality and human health. Bioconversion via black soldier fly larvae (BSFL; Hermitia illucens L.) is an expedient way for converting 'waste to resource' (insect protein and biofertilizer). Although researches abounded in laboratory-reared experiments and bioconversion mechanisms were pertinent, the void of data from actual and full-scale operation restricts the intensification of BSFL technology and its global adoption. Hence, a full-scale BSFL bioconversion system lasting 4 years in Hangzhou (China) was investigated, and the feasibility and efficiency of 15 tonnes of DBW per day were studied. Through continuous technical optimization, the average production of fresh larvae was increased from 8.5% in 2017 to 15.3% in 2020, along with bioconversion rate of final vermicompost decreased from 35.4% to 14.5%. The total biomass reduction rate in 2020 was 68.7 ± 17.4 kg/(m 3  d), equivalent to 0.735 ± 0.215 kg/(kg d) in the form of fresh larvae. Crude fat in fresh larvae accounted for 13.4%, and crude protein accounted for 16.2% in which the determined amino acid profile bore a strong resemblance to fish meal only except histidine and tyrosine. Its economic benefits proved the feasibility of this technology, and the profit reached up to 35.9 US$ per tonne of DBW in 2019. In conclusion, BSFL bioconversion system under current 'insect-farm' operation was a promising solution for DBW treatment with value-added waste recycling.

The practices of head and neck surgical oncologists must evolve to meet the unprecedented needs placed on our health care system by the Coronavirus disease 2019 (COVID-19) pandemic. Guidelines are emerging to help guide the provision of head and neck cancer care, though in practice, it can be challenging to operationalize such recommendations. Head and neck surgeons at Wuhan University faced significant challenges in providing care for their patients. Similar challenges were faced by the University of Toronto during the severe acute respiratory syndrome (SARS) pandemic in 2003. Herein, we outline our combined experience and key practical considerations for maintaining an oncology service in the midst of a pandemic., (© 2020 Wiley Periodicals, Inc.)

Objectives: We examined the prevalence and risk factors of migraine among the She population. The prevalence of migraine among She Chinese in Fujian province is high., Methods: This study is a cross-sectional survey. Subjects completed a questionnaire that collected demographic and clinical data related to migraine. Physical examination and clinical laboratory tests were performed. Data were analyzed by regression analysis., Results: Of the 5519 subjects enrolled, 2377 were male (43·1%) and 3142 female (56·9%). Of these, 581 (10·53%) experienced migraine annually, including 6·18% of males and 13·82% of females. Highest prevalence rate was among those aged 40-49 years (11·28%). The 141 (24·3%) subjects who had migraine with aura had higher incidence of family history of headache than those without aura (38·5% vs 19·9%, P < 0·0001)., Conclusion: Female gender and insomnia are possible risk factors for migraine in the She population.

By using soil and water assessment tool (SWAT) model, this paper simulated the surface runoff intensity and the export loadings of sediment particulates and nutrients via non-point source hydrological pathway in Tiaoxi watershed, and integrated with the simulation results, analyzed the temporal and spatial distribution characteristics of non-point source pollution in the watershed in 2008. In the study area, the per unit area non-point source pollution was stronger in northern region than in southern region and in eastern region than in western region, and the weakest in central region. Among the land utilization types, farmland had the biggest contribution to the sediment loading. There were significantly positive correlations between the loadings of surface runoff and associated sediment particulates and the rainfall intensity. The export loadings of nutrients through surface runoff were higher in rainy season (from June to September) than in dry season (from December to next March), and there existed significant correlations between the surface runoff loadings of sediment particulates, organic nitrogen, and nitrate and the average gradient of lands.

Nitrogen (N) and phosphorus (P) loss from rice paddy fields represents a significant threat to water quality in China. In this project, three irrigation-drainage regimes were compared, including one conventional irrigation-drainage regime, i.e. continuous submergence regime (CSR), and two improved regimes, i.e. the alternating submergence-nonsubmergence regime (ASNR) and the zero-drainage irrigation technology (ZDIT), to seek cost-effective practices for reducing nutrient loss. The data from these comparisons showed that, excluding the nutrient input from irrigation, the net exports of total N and total P via surface field drainage ranged from -3.93 to 2.39 kg ha and 0.17 to 0.95 g ha(-1) under the CSR operation, respectively, while N loss was -2.46 to -2.23 kg ha(-1) and P export was -0.65 to 0.31 kg ha(-1) under the improved regimes. The intensity of P export was positively correlated to the rate of P application. Reducing the draining frequency or postponing the draining operation would shift the ecological role of the paddy field from a nutrient export source to an interception sink when ASNR or the zero-drainage water management was used. In addition, since the rice yields are being guaranteed at no additional cost, the improved irrigation-drainage operations would have economic as well as environmental benefits.

Healthy wetland system is regarded as an effective way for biological remediation of non-point source pollutants. A case field investigation on phosphorus (P) status of overlying water and sediment was carried out for Xiazhuhu wetland located in Northern Zhejiang Province, China. A static wetland microcosm experiment was conducted to understand the characteristics and mechanisms related to P exchanging, P forms changing, and water quality impact across the interface of water and sediment. Field investigation showed that total P (TP) concentrations of sediments were found from 0.187 mg x g(-1) to 0.591 mg x g(-1), and TP in overlying water reached from 0.022 mg x L(-1) to 0.718 mg x L(-1) where the seasonal concentration variations of TP, dissolved P (DP), and particulate P (PP) were commonly found in order as winter > summer > spring > fall. Fed by synthetic solution containing P levels of 0.0 - 10.5 mg x L(-1), a 35-day-lasting microcosm study showed that P retention by sediments could be divided into three basic phases in order, i.e., buffer reaction, rapid adsorption, and slow adsorption. Under a typical stress concentration of 1.0 mg x L(-1) in overlying water, the increment of P tanks in different forms was found as NH4 Cl-P (0.0%), Fe-P/Mn-P (around 20%), NaOH-TP (around 66%, mainly as the form of Al-P), Ca-P (1.9%), and Res-P (11.3%), on the condition of Xiazhuhu wetland under low water season. Application of Al to wetland would increase the capacity of sediment P retention in Xiazhuhu wetland.

A near-trench paddy field experiment with five urea application rates (0-360 kg N ha(-1) in 90-kg increments) was conducted on a paddy soil in the Taihu Lake Region of China to elucidate N losses through lateral seepage during three rice (Oryza sativa L.) growing seasons. The total N (Nt), NH4(+) -N, and NO3(-) -N concentrations in the lateral seepage water increased with increasing N rates. The seasonal Nt fluxes by lateral seepage varied from 6.8 to 25.6 kg N ha(-1) for urea application rates of 90 to 360 kg N ha(-1). Lateral seepage accounted for 4.7 to 6.6% of the Nt applied, implying that lateral seepage was an important pathway of N loss from near-trench paddy fields. The cumulative N loss via lateral seepage was significantly related to N fertilization rate (P = 0.05). Floodwater level was also identified as a main factor affecting N losses via lateral seepage from paddy fields, as indicated by a positive linear relationship (R2 = 0.43) between floodwater level and daily lateral flow during the flooded period (P = 0.05). Under the conditions of these experiments, a shallow floodwater depth of 50 mm, urea application rates of 90 kg N ha(-1) or less, and no rainfall within 1 wk after N application reduced N losses by lateral seepage from paddy fields.

Loss of life expectancy (LLE) was used to evaluate and quantitate the health risk caused by carcinogen and non-carcinogen pollutants, and was proposed as a new method to compare the environmental health risk of different pollutants. The environmental health risks exposed by 6 major environmental pollutants in China, i.e., arsenic, DDTs, BaP, lead, cadmium and mercury, were evaluated and compared by using LLE. The LLE caused by carcinogen pollutants such as arsenic, DDTs and BaP are 3.6 d, 2.2 d and 12.1 d respectively, while the corresponding values caused by non-carcinogen pollutants such as lead,mercury and cadmium are 1.1 d, 1.7 d and 5.8 d respectively. Based on the studies published before, the rank of the health risk of the selected six environmental pollutants is BaP > cadmium > arsenic > DDTs > mercury > lead. The results reveal that the LLE can be utilized as a new index to evaluate and quantitate the health risk, and the environmental health risk caused by carcinogen and non-carcinogen pollutants can be compared within an unitive criterion by LLE.

Objective: To investigate the incidence and clinical and endoscopic characteristics of Barrett's esophagus (BE) and the relationship between BE and reflux esophagitis (RE)., Methods: Patients with BE were diagnosed according to new standard by endoscopy and histology. The prevalence, form in endoscopy, histology of biopsy, age, sex, symptom, Helicobacter pylori (Hp) infection and relationship between BE and RE were analyzed., Results: BE was 7.90% of the total endoscopy number, and male vs female was 1.98, mean age (45.1 +/- 14.8) years old. Only 19.15% of BE patients had typical reflux symptoms. 81.20% of BE patients were with short segment BE. Intestinal metaplasia was detected in 34.83% of BE and dysplasia 9.88%. 39.94% of BE patients were infected with Hp. Patients with RE (2.07%) were significantly less than those of BE (P < 0.01). 8.42% of BE patients were also with RE and 32.11% of RE patients were also with BE., Conclusions: The incidence of BE in Fujian of China is high. Most of BE are short segment BE and male and have no typical reflux symptoms. Intestinal metaplasia is found in 1/3 of BE patients. There isn't a close association between BE and RE.