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Sources and cycling of dissolved organic and inorganic carbon on the northern Qinghai-Tibetan Plateau: Radiocarbon results from Qinghai Lake

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SCIENCE OF THE TOTAL ENVIRONMENT 2022年第Part1期851卷 158123页

作者： Zhang, Hongmei Wang, Fuqiang Shan, Sen ren, Peng Luo, Chunle Fu, Wenjing Sun, shuwen Wang, Xuchen Ocean Univ China Frontiers Sci Ctr Deep Ocean Multispheres & Earth Key Lab Marine Chem Theory & Technol Qingdao Peoples R China Qingdao Natl Lab Marine Sci & Technol Qingdao Peoples R China State Ocean Adm North China Sea Environm Monitoring Ctr Qingdao Peoples R China Qingdao Natl Lab Marine Sci & Technol Ctr Isotope Geochem & Geochronol Qingdao Peoples R China

Tibetan Plateau lakes are sensitive to climate variabilities and affect regional temperature, precipitation and ecosystems. In this study, we investigated the concentrations and carbon isotope (14C and 13C) compositions of dissolved organic and inorganic carbon (DOC and DIC) along with the concentrations of major lithologic ions (Na+, Mg2+, K+, Ca2+) and dissolved silicate (DSi) in a large lake, namely, Qinghai Lake, and its seven inflowing rivers on the northeastern Qinghai-Tibetan Plateau of China. Our results revealed large differences in concentrations and isotopic compositions between DOC and DIC, as well as differences in the concentrations of major ions between the rivers and lake. The chemical weathering of carbonate and silicates in the catchments played important roles in con-trolling the fates of major ions in the rivers. In Qinghai Lake, evaporation resulted in 40-290 times the accumulation of Na+, Mg2+, and K+ observed in the rivers, while biological uptake and precipitation reduced the concentrations of Ca2+ and DSi in the lake by 4-17 times compared with those in the rivers. In addition, the concentrations of DOC and DIC in the lake were 6-7 times those in the rivers. The carbon isotope (delta 13C and & UDelta;14C) signatures of DOC and DIC revealed that the rivers transport millennium-aged DOC (1254 & PLUSMN;316 years) and DIC (1513 & PLUSMN;857 years), as influenced largely by the chemical weathering of rocks and preaged soil carbon on the plateau. In contrast, in Qinghai Lake, the ages of DOC are significantly younger (684 & PLUSMN;378 years) than the ages of riverine DOC, as regulated by newly biologically produced modern DOC. Moreover, the DIC ages in Qinghai Lake are all modern, indicating that exchange with atmospheric CO2 is the dominant process controlling the lake DIC. The accumulation and removal of riverine-aged DIC in Qinghai Lake, however, are not well understood, and the unbalanced radiocarbon in lake DIC remains a mystery that needs fu

关键词： Qinghai -Tibetan Plateau Qinghai Lake Carbon cycle Radiocarbon Stable carbon isotope

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Hydrophobic chitosan/salicylic acid blends film with excellent tensile properties for degradable food packaging plastic materials

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JOURNAL OF APPLIED POLYMER SCIENCE 2022年第43期139卷 e53042-e53042页

作者： Liu, Jin Wang, Tianhao Hu, Canmin Lei, Li Liang, Yu Gao, Zideng ren, Xueqin Hu, shuwen China Agr Univ Coll Resources & Environm Sci Beijing 100193 Peoples R China China Agr Univ Beijing Key Lab Farmland Soil Pollut Prevent & Re Beijing Peoples R China Minist Land & Resources China Key Lab Agr Land Qual Beijing Peoples R China

Degradable plastic materials made from biopolymer Chitosan (CS) present one of the alternatives to plastic bags for food packaging, but the stability and durability limits its application. Herein, we demonstrated a facile method of producing hydrophobic CS/salicylic acid (SA) film in organic phase for the first time. SA, which can destruct hydrogen bonds of CS was initially blended with CS in N, N-dimethylacetamide using a catalyst. On this basis, CS/SA blend was crosslinked via isocyanate to the hydrophobic CS-SA film. The derivatives structures were characterized using SEM, FTIR, UV-Vis, and fluorescence spectrum. The film-forming ability of CS was maintained, while the hydrophobicity, mechanical strength, and thermal stability of films were improved. These dramatic improvements occurred with the blending effects of CS and SA and the crosslinking effects of organic isocyanate cross linker. The permeabilities to water vapor and water-soluble substances of film were promoted, which are conducive to the application of the film as food packaging. The demonstration of bacteriostatic and grape preservation properties featured the super performance of the synthetic CS/SA film. Our work provides novel food preservation materials, which can replace the commonly used packaging materials and promote the development of the degradable food packaging plastic bags field.

关键词： degradation films hydrophobicity mechanical properties packaging

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“三权下放改革”对高校专利活动的影响研究——基于80所高校的实证分析

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中国科技论坛 2023年第10期 130-140页

作者：任知洋梅术文南京理工大学知识产权学院江苏南京210094

文章以2013—2020年中国80所高校作为研究样本,通过多期双重差分法测度改革对高校专利活动的效果。研究发现,“三权下放改革”对专利创造、专利质量、专利转化均产生正向影响,对产学研合作没有产生作用。从动态效应上看,改革对专利创造... 详细信息

文章以2013—2020年中国80所高校作为研究样本,通过多期双重差分法测度改革对高校专利活动的效果。研究发现,“三权下放改革”对专利创造、专利质量、专利转化均产生正向影响,对产学研合作没有产生作用。从动态效应上看,改革对专利创造和专利质量的促进效应比较稳定,对专利转化的促进效应则没有持续性。高校对科学技术和成果转化的内部激励强化了“三权下放改革”的效果,目前设立技术转移机构没有在改革中产生影响。此外,区域及高校办学层次异质性分析结果显示,改革效果在东部地区更为突出,“985工程”高校和“211工程”高校实施改革的差异主要体现在专利创造和专利转化上。

关键词：高校技术转移改革评估产权改革双重差分

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Responses of soil carbon cycling microbial functional genes to nitrogen and phosphorus addition in saline-sodic soils

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PLANT AND SOIL 2023年第1-2期490卷 261-277页

作者： Du, Xuejun Ge, Yanning Zhang, Yun Hu, Hao Zhang, Yiying Yang, Ziye ren, Xueqin Hu, shuwen Feng, Haojie Song, Yuling China Agr Univ Coll Resources & Environm Sci 2 Yuanmingyuan West Rd Beijing 100193 Peoples R China Shandong Agr Univ Coll Resources & Environm Natl Engn Res Ctr Efficient Utilizat Soil & Fertil Daizong Rd Tai An 271018 Shandong Peoples R China Hekou Dist Agr & Rural Bur Yellow River Rd 164 Dongying 257200 Shandong Peoples R China

AimsNitrogen (N) and phosphorus (P) have important roles in the terrestrial carbon (C) cycle. Nevertheless, the responses of microbial ecological functions involving C cycling in saline-sodic soils to N and P are barely known, particularly at the functional gene *** influence of N and P addition on C functional genes in saline-sodic soils was explored using a pot experiment. Eight treatments were conducted, namely: a control (CK), three N addition levels (NL, NM, and NH), three P addition levels (PL, PM, and PH), and combined N and P addition (NP).ResultsResults revealed that the total abundance of C functional genes was enhanced by the addition of N and P, promoting C fixation, degradation, and CH4 metabolism. The total gene abundance was the highest in NL among the three N addition treatments;however, the highest abundance was observed in PH among the three P addition treatments. Compared to CK, all treatments exerted greater effects on the abundance of genes related to recalcitrant C decomposition than on labile C decomposition. This was because increment in relative abundance of oligotrophic taxa was greater than that of copiotrophic taxa after the addition of N and P. Partial least squares path modeling analysis revealed that N and P addition regulated gene abundance by altering DOC, microbial diversity, and ESP, thereby directly influencing C *** results highlight that N and P stimulate the abundance of C functional genes via plant biomass and soil property traits in saline-sodic soils.

关键词： Saline-sodic soils Nitrogen addition Phosphorus addition Functional gene Carbon cycling Carbon mineralization

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科技成果权属混合所有制对高校创新效率的影响

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科技进步与对策 2023年第4期40卷 88-96页

作者：任知洋梅术文南京理工大学知识产权学院江苏南京210094

国内科技成果混合所有制试点已开展5年时间,旨在将科技成果部分产权分配给科研人员,通过权利变革改善高校科技创新状况。关于混合所有制试点对高校创新效率的影响,目前缺乏整体定量评价。运用双重差分法计算试点对高校创新效率的整体影... 详细信息

国内科技成果混合所有制试点已开展5年时间,旨在将科技成果部分产权分配给科研人员,通过权利变革改善高校科技创新状况。关于混合所有制试点对高校创新效率的影响,目前缺乏整体定量评价。运用双重差分法计算试点对高校创新效率的整体影响,进而测算产权结构变化对试点与高校创新效率间关系的影响。研究表明,科技成果混合所有制试点对高校创新效率具有正向影响,但因赋权而产生的高校与科研人员共有产权关系没有发挥试点改革对高校创新效率的促进作用,而高校与多元主体共有产权关系正向影响试点改革对高校创新效率的作用。最后,提出政策建议:加快构建精准的混合所有制权利配置体系,明晰主体间产权关系,推动高校与企业等创新主体开展高质量合作,逐步实现试点区域协同管理。

关键词：科技成果转化技术转移政策评估产权改革高校创新效率

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Effect of lateral inhomogeneous AlGaN barrier layer on electronic properties of GaN HEMTs

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MICRO AND NANOSTRUCTURES 2024年 191卷

作者： Guo, Yuchen ren, Yuke Peng, Zhihao Ma, Xiaochen Li, Shuti Zheng, shuwen South China Normal Univ Inst Semicond Sci & Technol Foshan 528225 Peoples R China South China Normal Univ Guangdong Engn Res Ctr Optoelect Funct Mat & Devic Inst Semicond Guangzhou 510631 Peoples R China

In this study, an AlGaN/GaN high electron mobility transistor with lateral inhomogeneous AlGaN barrier layer (LI-AlGaN HEMT) is proposed and studied systematically. The LI-AlGaN HEMT comprises three AlGaN regions with varying Al content, connected to the source, gate, and drain, respectively. With the increase of Al content in each region, the saturation current of the LI-AlGaN HEMT increases gradually, while the on -resistance (R on ) and breakdown voltage (BV) decrease. The threshold voltage (V th ) of the LI-AlGaN HEMT depends only on the Al content of AlGaN beneath the gate. By introducing the source field plate (FP), the calculated output current of the conventional FP-HEMT is consistent with the experimental data. After optimizing Al content, the LI-AlGaN FP-HEMT has the same V th compared with conventional FP-HEMT. However, the saturation current is increased by approximately 20 % and the R on is decreased by approximately 30 %. Additionally, the BV is increased to 1008 V. So the optimized lateral inhomogeneous AlGaN HEMT has better DC characteristics and is suitable for high power GaN device applications.

关键词： AlGaN/GaN HEMT Lateral inhomogeneous channel Threshold voltage Breakdown voltage

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Comparison of deep learning-assisted blinking analysis system and Lipiview interferometer in dry eye patients: a cross-sectional study

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EYE AND VISION 2024年第1期11卷 1页

作者： ren, Yueping Wen, Han Bai, Furong Huang, Binge Wang, Zhenzhen Zhang, shuwen Pu, Yaojia Le, Zhenmin Gong, Xianhui Wang, Lei Chen, Wei Zheng, Qinxiang Wenzhou Med Univ Eye Hosp Natl Clin Res Ctr Ocular Dis Wenzhou 325027 Zhejiang Peoples R China Wenzhou Med Univ Sch Ophthalmol & Optometry 270 Xueyuan West Rd Wenzhou 325027 Zhejiang Peoples R China

BackgroundAbnormal blinking pattern is associated with ocular surface diseases. However, blink is difficult to analyze due to the rapid movement of eyelids. Deep learning machine (DLM) has been proposed as an optional tool for blinking analysis, but its clinical practicability still needs to be proven. Therefore, the study aims to compare the DLM-assisted Keratograph 5M (K5M) as a novel method with the currently available Lipiview in the clinic and assess whether blinking parameters can be applied in the diagnosis of dry eye disease (DED).MethodsThirty-five DED participants and 35 normal subjects were recruited in this cross-sectional study. DED questionnaire and ocular surface signs were evaluated. Blinking parameters including number of blinks, number of incomplete blinking (IB), and IB rate were collected from the blinking videos recorded by the K5M and Lipiview. Blinking parameters were individually collected from the DLM analyzed K5M videos and Lipiview generated results. The agreement and consistency of blinking parameters were compared between the two devices. The association of blinking parameters to DED symptoms and signs were evaluated via *** total, 140 eyes of 70 participants were included in this study. Lipiview presented a higher number of IB and IB rate than those from DLM-assisted K5M (P <= 0.006). DLM-assisted K5M captured significant differences in number of blinks, number of IB and IB rate between DED and normal subjects (P <= 0.035). In all three parameters, DLM-assisted K5M also showed a better consistency in repeated measurements than Lipiview with higher intraclass correlation coefficients (number of blinks: 0.841 versus 0.665;number of IB: 0.750 versus 0.564;IB rate: 0.633 versus 0.589). More correlations between blinking parameters and DED symptoms and signs were found by DLM-assisted K5M. Moreover, the receiver operating characteristic analysis showed the number of IB from K5M exhibiting the highest area under curve of 0.773.C

关键词： Incomplete blinking Deep learning model Dry eye disease

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Performance and mechanisms of biochar-assisted vermicomposting in accelerating di-(2-ethylhexyl) phthalate biodegradation in farmland soil

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JOURNAL OF HAZARDOUS MATERIALS 2023年第PartB期443卷 130330页

作者： Zhen, Zhen Luo, shuwen Chen, Yijie Li, Gaoyang Li, Huijun Wei, Ting Huang, Fengcheng ren, Lei Liang, Yan-Qiu Lin, Zhong Zhang, Dayi Guangdong Ocean Univ Coll Coastal Agr Sci Zhanjiang 524088 Peoples R China Guangdong Ocean Univ Fac Chem & Environm Sci Zhanjiang 524088 Peoples R China Guangdong Ocean Univ Shenzhen Res Inst Shenzhen 518108 Peoples R China Jilin Univ Coll New Energy & Environm Changchun 130021 Peoples R China Jilin Univ Key Lab Groundwater Resources & Environm Minist Educ Changchun 130021 Peoples R China

Biochar and earthworms can accelerate di-(2-ethylhexyl) phthalate (DEHP) degradation in soils. However, little is known regarding the effect of biochar-assisted vermicomposting on soil DEHP degradation and the underlying mechanisms. Therefore, the present study investigated DEHP degradation performance and bacterial community changes in farmland soils using earthworms, biochar, or their combination. Biochar-assisted vermicomposting significantly improved DEHP degradation through initial physical adsorption on biochar and subsequent rapid biodegradation in the soil, earthworm gut, and charosphere. Burkholderiaceae, Pseudomonadaceae, and Flavobacteriaceae were the potential DEHP degraders and were enriched in biochar-assisted vermicomposting. In particularly, Burkholderiaceae and Sphingomonadaceae were enriched in the earthworm gut and charosphere, possibly explaining the mechanism of accelerated DEHP degradation in biochar-assisted vermicomposting. Soil pH, soil organic matter, and humus (humic acid, fulvic acid, and humin) increased by earthworms or biochar enhanced DEHP degradation. These findings imply that biochar-assisted vermicomposting enhances DEHP removal not only through rapid physical sorption but also through the improvement of soil physicochemical characteristics and promotion of degraders in the soil, earthworm gut, and charosphere. Overall, biochar-assisted vermicomposting is a suitable method for the remediation of organic-contaminated farmland soils.

关键词： Soil Biochar Earthworm Microbial communities Di-(2-ethylhexyl) phthalate

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Machine learning assisted dual-emission fluorescence/colorimetric sensor array detection of multiple antibiotics under stepwise prediction strategy

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SENSORS AND ACTUATORS B-CHEMICAL 2022年第0期359卷 131590-131590页

作者： Xu, Zijun Wang, Kejia Zhang, Mengqian Wang, Tianhao Du, Xuejun Gao, Zideng Hu, shuwen ren, Xueqin Feng, Haojie China Agr Univ Coll Resources & Environm Sci Beijing 100193 Peoples R China Beijing Key Lab Farmland Soil Pollut Prevent & Re Beijing 100193 Peoples R China Shandong Agr Univ Coll Resources & Environm Sci Natl Engn Lab Efficient Utilizat Soil & Fertilize Tai An 271018 Shandong Peoples R China

Effective sensors to detect antibiotics as environmental and health hazards are urgently needed. Herein, we constructed a dual-emission fluorescence/colorimetric sensor array based on novel high fluorescence quantum yield carbon dots and CdTe quantum dots. Multi-dimensional data (fluorescence intensities and maximum emission wavelengths) was used to establish a sensor array platform with improved specificity. To meet the challenges of establishing a unified model and detecting outside datasets samples, we innovatively built a unified SX-model using a "stepwise prediction" strategy combined with machine learning to screen optimal methods. By integrating classification and concentration models under a tree-based pipeline optimization technique framework, the extreme random forest was selected as the most accurate classification model. The sensor array detected nine antibiotics at 0.5-50 mu M with 95% accuracy and 4.93% average concentration error for unknown samples outside the datasets. Simultaneous identification of binary and ternary mixed samples was also enhanced. Furthermore, antibiotics in 216 river water and milk samples were discriminated with 100% accuracy and 3.25% and 4.43% average concentration errors of unknown samples outside the datasets, respectively. Finally, antibiotics were completed visually identified. The proposed original SX-model assisted dual-emission sensor not only overcomes low specificity and immobility, but breaks the bottleneck of existing analysis methods showing great application potential in the array detection field.

关键词： Carbon dots Dual emission sensor array Antibiotics Stepwise prediction Machine learning

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The association between stroke and COVID-19-related mortality: a systematic review and meta-analysis based on adjusted effect estimates

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NEUROLOGICAL SCIENCES 2022年第7期43卷 4049-4059页

作者： Li, shuwen ren, Jiahao Hou, Hongjie Han, Xueya Xu, Jie Duan, Guangcai Wang, Yadong Yang, Haiyan Zhengzhou Univ Sch Publ Hlth Dept Epidemiol 100 Sci Ave Zhengzhou 450001 Peoples R China Henan Ctr Dis Control & Prevent Dept Toxicol Zhengzhou 450016 Peoples R China

Objective To investigate the association between stroke and the risk for mortality among coronavirus disease 2019 (COVID-19) patients. Methods We performed systematic searches through electronic databases including PubMed, Embase, Scopus, and Web of Science to identify potential articles reporting adjusted effect estimates on the association of stroke with COVID-19-related mortality. To estimate pooled effects, the random-effects model was applied. Subgroup analyses and meta-regression were performed to explore the possible sources of heterogeneity. The stability of the results was assessed by sensitivity analysis. Publication bias was evaluated by Begg's test and Egger's test. Results This meta-analysis included 47 studies involving 7,267,055 patients. The stroke was associated with higher COVID-19 mortality (pooled effect = 1.30, 95% confidence interval (CI): 1.16-1.44;I-2 = 89%, P < 0.01;random-effects model). Subgroup analyses yielded consistent results among area, age, proportion of males, setting, cases, effect type, and proportion of severe COVID-19 cases. Statistical heterogeneity might result from the different effect type according to the meta-regression (P = 0.0105). Sensitivity analysis suggested that our results were stable and robust. Both Begg's test and Egger's test indicated that potential publication bias did not exist. Conclusion Stroke was independently associated with a significantly increased risk for mortality in COVID-19 patients.

关键词： COVID-19 Stroke Mortality Adjusted effect estimates Meta-analysis

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