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Adaptation of microbial communities to multiple stressors associated with litter decomposition of Pterocarya stenoptera

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Journal of Environmental Sciences 2014年第5期26卷 1001-1013页

作者： Gaozhong Pu Jingjing Tong Aimeng Su Xu Ma Jingjing Du Yanna Lv Xingjun Tian School of Life Science Nanjing University guangxi institute of Botany Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences

To understand the further impacts of multiple stressors in freshwater, we investigated the effects of heavy metal （HM, Cu and Zn） and nutrient enrichments （nitrogen and phosphorus, NP） on microbial decomposition of Pterocarya stenoptera litter and the associated extracellular enzyme activities and microbial biomass with microcosms. Results showed that the decomposition rates were slower in the polluted stream waters than those in the unpolluted ones, which corresponded to lower microbial biomass and integrated enzyme activities of cellulose and ^-glucosidase. The decomposition rates were accelerated at low HM level, which was associated with the stimulated enzyme activities of hydrolytic enzymes or was stimulated by both NP levels in polluted stream waters. In particular, the hydrolase enzyme activities of microbial communities in polluted stream waters were stimulated by low HM level, suggesting that low HM level-stimulated litter decomposition may be due to the increased enzymatic activities. When microbial communities were exposed to HM and NP simultaneously, the inhibitory effect （in unpolluted stream waters） or the stimulated effect （in polluted stream waters） of low HM concentration was enhanced and attenuated, respectively, which suggests that the NP antagonistic effect against HM toxicity on litter decomposition may contribute to the litter- associated extracellular enzyme activities. These results suggest that the may have antagonistic effects on stream ecosystem functioning. of HM and NP

关键词： leaf decomposition heavy metal and nutrient mixture extracellular enzyme activity community adaptation microbial community

Effects of Selenium and Cobalt on Germination of Alfalfa(Medicago sativa) at Different Temperatures

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animal husbandry and Feed Science 2019年第3期11卷 115-118,124页

作者： Shi Jing Wei Jinyi Lan Xi Qiu Jinhua Deng Suyuan Yao Na animal husbandry research institute of guangxi zhuang autonomous region

Taking No.3 alfalfa(Medicago sativa)as the material,the effects of selenium and cobalt elements on seed germination of alfalfa at different temperatures were studied through germination *** results showed that selenium and cobalt promoted seed germination of alfalfa,and improved germination potential,germination rate,germination index and vigor *** the increasing proportion of selenium and cobalt,the numerical value of each index first increased then *** seed germinations in A15 and B12 treatments were the best at 10℃ and 20℃,while those in A1 and B1 treatments were the worst.

关键词： Selenium Cobalt Alfalfa Germination

Feeding Effect of Codariocalyx gyroides on Meat Rabbits

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animal husbandry and Feed Science 2019年第1期11卷 9-11页

作者： Yao Na Huang Yilong Zeng Fanquan Deng Suyuan Lai Dawei Wei Jinyi animal husbandry research institute of guangxi zhuang autonomous region

To explore the feeding effect of Codariocalyx gyroides on meat rabbits, 30 healthy meat rabbits at the age of 50 days were randomly divided into five groups(Ⅰ,Ⅱ,Ⅲ,Ⅳ and Ⅴ), six rabbits each group. Rabbits in experimental groups Ⅰ,Ⅱ,Ⅲ and Ⅳ were fed with different quantita-tive complete formula feed and unlimited fresh grass of C. gyroides, and those in group Ⅴ(control group) were fed with complete formula feed. The indicators such as feed intake and growth performance were measured after 60 d. The results showed that the gaining effects of meat rabbits in ex-perimental groups Ⅳ and Ⅲ were most obvious, and the daily gain reached(25.75 ±3.00) and(24.50±1.95) g, 20.72% and 14.86% higher than those in control group, respectively. The conversion efficiency of dry matter in experimental group Ⅲ was the highest, and only 2.99 g of C. gyroides and compound feed dry matter was consumed for the growth of 1 g of rabbit meat, receiving significant economic benefit.

关键词： Codariocalyx gyroides Meat rabbit Growth performance Economic benefit Forage conversion efficiency

Seasonal dynamics of soil microbial biomass C and N of Keteleeria fortunei var. cyclolepis forests with different ages

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Journal of Forestry research 2020年第6期31卷 2377-2384页

作者： Yong Wang Xiongsheng Liu Fengfan Chen Ronglin Huang Xiaojun Deng Yi Jiang guangxi Key Laboratory of Superior Trees Resource Cultivation Guangxi Zhuang Autonomous Region Forestry Research InstituteNanning 530002People’s Republic of China

Soil microbial biomass is an important indicator to measure the dynamic changes of soil carbon *** is of great signifi cance to understand the dynamics of soil microbial biomass in plantation for rational management and cultivation of *** order to explore the temporal dynamics and infl uencing factors of soil microbial biomass of Keteleeria fortunei *** at diff erent stand ages,the plantation of diff erent ages(young forest,5 years;middle-aged forest,22 years;mature forest,40 years)at the guangxi Daguishan forest station of China were studied to examine the seasonal variation of their microbial biomass carbon(MBC)and microbial biomass nitrogen(MBN)by chloroform fumigation extraction *** was found that among the forests of diff erent age,MBC and MBN diff ered signifi cantly in the 0–10 cm soil layer,and MBN diff ered signifi cantly in the 10–20 cm soil layer,but there was no signifi cant diff erence in MBC for the 10–20 cm soil layer or in either MBC or MBN for the 20–40 cm soil *** increasing maturity of the forest,MBC gradually decreased in the 0–10 cm soil layer and increased fi rstly and then decreased in the 10–20 cm and 20–40 cm soil layers,and MBN increased fi rstly and then decreased in all three soil *** the soil depth increased,both MBC and MBN gradually decreased for all three *** MBC and MBN basically had the same seasonal variation in all three soil layers of all three forests,i.e.,high in the summer and low in the *** analysis showed that MBC was signifi cantly positively correlated with soil organic matter,total nitrogen,and soil moisture,whereas MBN was signifi cantly positively correlated with soil total *** showed that soil moisture content was the main factor determining the variation of soil microbial biomass by Redundancy *** results showed that the soil properties changed continuously as the young forest grew into the middle-aged forest,which increased soil micro

关键词： Microbial biomass Soil microbial nitrogen Soil microbial carbon Seasonal variation Artifi cial forest Keteleeria fortunei var.cyclolepis

Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: A case study at Lihu,South China

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Journal of Environmental Sciences 2014年第11期26卷 2222-2230页

作者： Liankai Zhang Hui Yang Jiansheng Tang Xiaoqun Qin Au Yik Yu institute of Karst Geology Chinese Academy of Geological Sciences Karst Dynamics Laboratory Ministry of Land and Resources and Guangxi Zhuang Autonomous Region

Arsenic （As） pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As（III） accounts for 51.0% ± 9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As（III） and As（V） in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis （RDA）. Eight main factors, i.e., sediment iron （SFe）, sediment aluminum （SAI）, sediment calcium （SCa）, sediment organic matter （SOM）, sediment manganese （SMn）, water calcium （WCa^2＋）, water magnesium （WMg^2＋）, and water bicarbonate ion （WILCOX） were extracted from thirteen indicators. Their impacts on arsenic content rank as： SFe〉SCa〉WCa^2＋〉SAl〉wHCO3^-〉SMn〉SOM〉WMg^2＋. Of these factors, SFe, SAl, SCa, SOM, SMn, WMg^2＋ and WCa＆2＋ promote arsenic attenuation, whereas WHCO3^- inhibits it. Further investigation revealed that the redox potential （Eh） and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water.

关键词： Karst subterranean stream Sediment Arsenic Geochemical factors Redundancy analysis

Frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 374-379页

作者： Jie Cai Wen-Wen Fan Yun-Hui Zhong Cai-Lan Wen Xiao-Dan Wei Wan-Chen Wei Wan-Yan Xiang Jin-Mao Chen Department of Ophthalmology First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Digital and Intelligent Technology Transformation and Application research institute of Visual Function Tianjin 300000China guangxi Medical University Nanning 530021Guangxi Zhuang Autonomous RegionChina

AIM:To investigate the frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university ***:Totally 158 student volunteers underwent routine vision examination in the optometry clinic of guangxi Medical *** data were used to identify the different types of accommodation and nonstrabismic binocular vision dysfunction and to determine their *** analysis and logistic regression were used to examine the factors associated with these ***:The results showed that 36.71%of the subjects had accommodation and non-strabismic binocular vision issues,with 8.86%being attributed to accommodation dysfunction and 27.85%to binocular *** insufficiency(CI)was the most common abnormality,accounting for 13.29%.Those with these abnormalities experienced higher levels of eyestrain(χ2=69.518,P<0.001).The linear correlations were observed between the difference of binocular spherical equivalent(SE)and the index of horizontal esotropia at a distance(r=0.231,P=0.004)and the asthenopia survey scale(ASS)score(r=0.346,P<0.001).Furthermore,the right eye's SE was inversely correlated with the convergence of positive and negative fusion images at close range(r=-0.321,P<0.001),the convergence of negative fusion images at close range(r=-0.294,P<0.001),the vergence facility(VF;r=-0.234,P=0.003),and the set of negative fusion images at far range(r=-0.237,P=0.003).Logistic regression analysis indicated that gender,age,and the difference in right and binocular SE did not influence the emergence of these ***:Binocular vision abnormalities are more prevalent than accommodation dysfunction,with CI being the most frequent *** binocular refractive disparity leads to more severe eyestrain symptoms.

关键词： optometry clinic non-strabismic binocular vision dysfunction college students convergence insufficiency

Relationships between leaf color changes,pigment levels,enzyme activity,photosynthetic fluorescence characteristics and chloroplast ultrastructure of Liquidambar formosana Hance

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Journal of Forestry research 2022年第5期33卷 1559-1572页

作者： Guoping Yin Yong Wang Yufei Xiao Jisheng Yang Renjie Wang Ying Jiang Ronglin Huang Xiongsheng Liu Yi Jiang guangxi Key Laboratory of Superior Trees Resource Cultivation Guangxi Zhuang Autonomous Region Forestry Research InstituteNanning 530002People’s Republic of China guangxi University Nanning 53000People’s Republic of China

Liquidambar formosana Hance is an attractive landscape tree species because its leaves gradually change from green to red,purple or orange in *** this study,the red variety of *** was used to establish a quantitative model of leaf *** changes in leaf color,pigment levels,enzyme activity,photosynthetic fluorescence characteristics and chloroplast ultrastructure were *** relationship between leaf color and physiological structure indices was quantitatively analyzed to systematically explore the mechanisms behind leaf *** data showed that with a decrease in external temperatures,chloroplast numbers and sizes gradually decreased,thylakoid membranes became distorted,and chlorophyll synthesis was blocked and gradually *** a result,chloroplast membranes could not be biosynthesized normally;net photosynthesis,maximum and actual photochemical efficiency,and rate of electron transfer decreased *** light energy caused leaf *** intensification of photoinhibition,leaves protected themselves using two *** the first,anthocyanin synthesis was promoted by increasing chalcone isomerase and flavonoid glycosyltransferase activities and soluble sugar content so as to increase anthocyanin to filter light and eliminate reactive oxygen species to reduce *** the second,excessive light energy was consumed in the form of heat energy by increasing the non-photochemical quenching *** processes tuned the leaves red.

关键词： Anthocyanins Leaf color parameter Enzymatic activities Chlorophyll fluorescence characteristics Liquidambar formosana

Effectiveness of hospital disinfection and experience learnt from 11 years of surveillance

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The Journal of Biomedical research 2019年第6期33卷 408-413页

作者： Chun’ai Tao Yongxin Gan Weidong Su Zhutian Li Xiaolan Tang Center for Disease Prevention and Control of guangxi zhuang autonomous region

This survey was designed to assess the sanitation status of hospitals and the compliance of hospital staff to disinfection strategies within the past 11 years.A total of 199 provincial affiliated tertiary or secondary public hospitals from 2007 to 2017 were investigated and seven critical categories,namely indoor air,work surface,hand hygiene,ultraviolet(UV) irradiation intensity,use of disinfectants,sterilization of medical items,and effects of steam sterilizer,were *** average qualified rates were(94.74±3.54)%(810/855),(97.25±1.65)%(1 876/1 929),(87.57±4.60)%(2 508/2 864),(95.00±4.50)%(1 196/1 259),and(98.76±1.14)%(1 599/1 619) for indoor air,work surface,hand hygiene,UV irradiation intensity,and sterilization of medical items,*** terms of other categories,a few samples were not qualified:3/1 575 for use of disinfectants and 1/243 for effects of steam *** hospital disinfection monitoring and supervision program effectively improved the effectiveness of *** monitoring and supervision must be conducted to ensure a safe hospital treatment environment.

关键词： hospital disinfection indoor air hand hygiene work surface ultraviolet irradiation intensity surveillance program

research and implementation of a universal workflow model to evaluate the soil fertility based on OGC Web Service

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Geo-Spatial Information Science 2018年第4期21卷 346-357页

作者： Yan Ren Jiaying Chen Lankang Chen Haitao Zhang Ke Zhang Land Surveying and Mapping institute of guangxi zhuang autonomous region NanningChina College of Resources and Environment Huazhong Agricultural UniversityWuhanChina

A method based on workflow technology and Open Geospatial Consortium(OGC)specification is proposed to establish a universal workflow conceptual model in the network *** this paper,the soil fertility evaluation conceptual model was developed as an evaluation method of soil fertility by analyzing the GIS-based fertility evaluation method and extracting the dynamic variable to verify the feasibility *** validation process involves determining the instantiation of the conceptual *** proposed conceptual model achieved the following *** data acquisition and processing functions were packaged into an OGC-compliant service model;these service models were organized into a processing chain in a certain order on the workflow platform by Petri-Net;the fertility evaluation was realized on the workflow platform by calling the processing *** showed that processing functions and data can be shared in the network environment,and the network workflow model can be realized by the workflow *** successful implementation of fertility evaluation proved the feasibility of the network-based universal workflow conceptual *** addition,the flexibility of our modeling method is demonstrated by reconstructing the workflow model.

关键词： OGC Web Service conceptual model workflow fertility evaluation