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High Performance Liquid Chromatographic Identification and Estimation of Phthalates in Sewer Waste and a Receiving River in Ibadan City, Southwestern Nigeria

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Journal of Water Resource and Protection 2012年第10期4卷 851-858页

作者： gregory O. Adewuyi Department of Chemistry University of Ibadan Ibadan Nigeria

medical wastes have been implicated in river pollution in developing countries and most often people depend on water from such rivers for sources of livelihood. Phthalates (endocrine disruptors) are major components in medical wastes and are commonly found contaminants in aquatic environment. most sewage treatment facilities handling medical waste are inefficient due to overuse and poor maintenance and discharge directly into rivers. This study aimed to investigate the identity and estimates the concentration of phthalates in supposed treated medical wastes from a hospital sewer and water from a receiving river. Samples were randomly collected before and after treatment by the sewer plants, while samples were randomly collected along the course of the river starting from point of discharge. Control samples were taken from upstream about 500 m along the river course. The samples were extracted by liquid-liquid chroma- tographic process using dichloromethane, after which they were cleaned up in a column of silica gel using hexane as the mobile solvent. The cleaned extracts were analyzed by HPLC. The concentrations (μg/L) of dimethyl-, diethyl-, diphenyl-, dibutyl- and di-(2-ethyl)hexyl phthalates ranged from 62.81 ± 18.53;4.74 ± 3.57;2.05 ± 1.80;11.40 ± 5.58 to 141.92 ± 35.8 respectively in the sewer waste. The receiving river had a concentration (μg/L) of 9.17 ± 14.02;0.18 ± 0.31;0.48 ± 0.84;2.84 ± 1.21;61.72 ± 38.35 respectively for dimethyl-, diethyl-, diphenyl-, dibutyl- and di-(2-ethyl) hexyl phthalates. These concentrations were higher than control and far exceeded the USEPA limits of 3 μg/l recom- mended for phthalates in water. Contaminants of aquatic environment by untreated wastes from hospitals has serious implications on public health and environment as human risks for phthalate esters downstream are high and this calls for urgent need to develop strategy to build incentives for compliance in treatment and discharge of wastes into river waters.

关键词： Sewage Treatment Phthalates Liquid-Liquid Extraction Clean-Up Effluent Toxicity

Drying conditions in Switzerland-indication from a 35-year Landsat time-series analysis of vegetation water content estimates to support SDGs

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Big Earth Data 2021年第4期5卷 445-475页

作者： Charlotte Poussin Alexandrine massot Christian Ginzler Dominique Weber Bruno Chatenoux Pierre Lacroix Thomas Piller Liliane Nguyen gregory Giuliani Institute for Environmental Sciences University of GenevaGenevaSwitzerland Swiss Federal Institute for Forest Snow and Landscape Research WSLBirmensdorfSwitzerland Institute for Environmental Sciences Gap Non-linearity and Climate GroupUniversity of GenevaGenevaSwitzerland

Exacerbated by climate change,Europe has experienced series of hot and dry summer since the beginning of the 21st *** importance of land conditions became an international concern with a dedicated sustainable development goal(SDG),the SDG *** calls for developing and finding innovative solu-tions to follow and evaluate impacts of changing land condi-tions induced by various driving *** Switzerland,drought risk will significantly increase in the coming decades with severe consequences on agriculture,energy production and *** this paper,we used a 35-year satellite-derived annual and seasonal times-series of normalized difference water index(NDWI)to follow vegetation water content evolution at different spatial and temporal scales across Switzerland and related them to temperature and precipitation to investigate possible responses of changing climatic *** indicate that there is a small and slow drying tendency at the country scale with a NDWI mean decreasing slope of−0.22%/year for the 23%significant pixels across *** tendency is mostly visible below 2000 m above sea level(m.a.s.l.)and in all biogeographical *** Southern Alps regions appear to be more responsive to changing drying conditions with a significant and slight negative NDWI trend(−0.39%/year)over the last 35 ***,NDWI values are mostly a func-tion of temperature at elevations below the tree line rather than *** suggest that multi-annual and seasonal NDWI can be a valuable indicator to monitor vegetation water content at different scales,but other components such as land cover type and evapotranspiration should be considered to better characterize NDWI *** Earth Observations data can provide valuable complementary obser-vations for national statistics on the ecological state of vegeta-tion to support SDG 15 to monitor land affected by drying conditions.

关键词： Climate change vegetation NDWI Landsat drought SDG 15 land degradation ecosystems Earth Observation big Earth data Switzerland

China's great wall, Israel's Bar Lev Line, and passive infectious disease surveillance

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Journal of medical Colleges of PLA(China) 2014年第2期29卷 77-79页

作者： maha A Elbadry mary m merrill meng-meng ma mai-Juan ma Jia-Hai Lu Wu-Chun Cao gregory C Gray One Health Center of Excellence for Research and Training College of Public Health and Health Professions University of Florida P.O. Box 100188Gainesville FL 32610 USA School of Public Health Key Laboratory of Tropical Disease Control Research Ministry of Education Sun Yat-sen University State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology

Emerging infectious diseases are some of modern society's greatest threats. Like some great construction efforts designed to protect mankind, current public health measures against these emerging pathogens have not always been successful. This paper highlights the importance of embracing new interdisciplinary approaches towards emerging pathogen threats. One such approach, termed One Health, is quickly being embraced by professional organizations and public health institutions across the world as a way forward. This paper briefly discusses the above problems and preliminary steps taken by Chinese academic institutions to embrace the One Health approach.

关键词： zoonoses communicable diseases emerging epidemiology public health one health

New insights into the role of DNA synthesis in meiotic recombination

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Science Bulletin 2016年第16期61卷 1260-1269页

作者： Jiyue Huang gregory P. Copenhaver Hong ma Yingxiang Wang State Key Laboratory of Genetic Engineering and CollaborativeInnovation Center for Genetics and Development Ministry ofEducation Key Laboratory of Biodiversity Science andEcological Engineering and Institute of Biodiversity SciencesInstitute of Plants Biology Center for Evolutionary BiologySchool of Life Sciences Fudan University Shanghai 200438China Department of Biology and the Carolina Center for GenomeSciences University of North Carolina at Chapel Hill ChapelHill NC 27599-3280 USA Lineberger Comprehensive Cancer Center University of NorthCarolina School of Medicine Chapel Hill NC 27599-3280 USA Institutes of Biomedical Sciences Fudan UniversityShanghai 200032 China

meiosis comprises two rounds of nuclear division following a single phase of DNA replication, leading to the production of haploid gametes and is essential for sexual reproduction in eukaryotes. Unlike mitosis, meiosis involves homologous chromosome pairing, synapsis, and recombination during prophase I. meiotic recombination not only ensures the accurate segregation of homologs, but also redistributes alleles among offspring. DNA synthesis is a critical process during meiotic recombination, but our understanding of the proteins that execute and regulate it is limited. This review summarizes the recent advances in defining the role of DNA synthesis in meiotic recombina- tion through analyses of DNA synthesis genes, with specific emphasis on DNA polymerases （e.g., Pole and PolS）, replication processivity factor RFC1 and translesion polymerases （e.g., Pol~）. We also present a new double strand break repair model for meiotic recombination, which includes lagging strand DNA synthesis and leading strand elongation. Finally, we propose that DNA synthesis is one of critical factors for discriminating meiotic recombination pathways and that this differentiation may be conserved among eukaryotes.

关键词： meiotic recombination DNA synthesis Crossover associated conversion tract

Tailoring spin mixtures by ion-enhanced maxwell magnetic coupling in colortunable organic electroluminescent devices

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Light(Science & Applications) 2018年第1期7卷 629-640页

作者： Junwei Xu Yue Cui gregory m.Smith Peiyun Li Chaochao Dun Linqi Shao Yang Guo Hongzhi Wang Yonghua Chen David L.Carroll Center for Nanotechnology and molecular materials Wake Forest UniversityWinston-SalemNC 27109USA Department of Physics Wake Forest UniversityWinston-SalemNC 27106USA Key Laboratory of Luminescence and Optical Information(ministry of Education) Institute of Optoelectronics TechnologyBeijing Jiaotong University100044 BeijingP.R.China Department of Electro-Optics School of EngineeringUniversity of DaytonDaytonOH 45469USA Department of mathematics Wake Forest UniversityWinston-SalemNC 27106USA State Key Laboratory for modification of Chemical Fibers and Polymer materials 201620 ShanghaiP.R.China College of materials Science and Engineering Donghua University201620 Shanghai P.R.China Institute of Advanced materials Nanjing Tech University211816 NanjingJiangsuP.R.China Department of Physics and Astronomy College of CharlestonCharlestonSC 29424USA

In this work,we show that the spin dynamics of excitons can be dramatically altered by maxwell magnetic field coupling,together with an ion-enhanced,low-internal-splitting-energy organic semiconducting *** employing a unique,alternating current(AC)-driven organic electroluminescent(OEL)device architecture that optimizes this magnetic field coupling,almost complete control over the singlet-to-triplet ratio(from fluorescent to phosphorescent emission in a single device)is *** attribute this spin population control to magnetically sensitive polaron–spin pair intersystem crossings(ISCs)that can be directly manipulated through external driving *** an illustration of the utility of this approach to spin-tailoring,we demonstrate a simple hybrid(double-layer)fluorescence–phosphorescence(F–P)device using a polyfluorene-based emitter with a strong external Zeeman effect and ion-induced long carrier *** control over de-excitation pathways is achieved by controlling the device-driving frequency,resulting in complete emission blue–red color *** photoluminescence(PL)spectroscopy directly confirms that this color control derives from the magnetic manipulation of the singlet-totriplet *** results may pave the way to far more exotic organic devices with magnetic-field-coupled organic systems that are poised to usher in an era of dynamic spintronics at room temperature.

关键词： temperature. coupling maxwell

Effect of Impaired Lung Function on the Development and Progression of Endobronchial Premalignant Lesions

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Journal of Cancer Therapy 2012年第4期3卷 364-371页

作者： Vijayvel Jayaprakash gregory m. Loewen martin C. mahoney Samjot Dhillon Sai Yendamuri D. Kyle Hogarth Enrique machare-Delgado Ravi J. menezes Sandra m. Jacob mary E. Reid Cancer Prevention and Population Sciences Roswell Park Cancer Institute Buffalo USA Department of medical Imaging University Health Network Toronto Canada Department of medicine Roswell Park Cancer Institute Buffalo USA Department of Social and Preventive medicine State University of New York at Buffalo Buffalo USA Department of Thoracic Surgery Roswell Park Cancer Institute Buffalo USA Pulmonary Oncology Sacred Heart Medical Center Spokane USA School of medicine State University of New York at Buffalo Buffalo USA Section of Pulmonary and Critical Care medicine University of Chicago Chicago USA

Background: Chronic obstructive pulmonary disease (COPD) and presence of endobronchial premalignant lesions (EPL) are individual risk factors for lung cancer (LC). However, effect of impaired lung function (ILF) on the natural history of EPL has not been explored. Patients and methods: This study included 217 high-risk participants from a hospital-based LC surveillance cohort who underwent pulmonary function testing followed by bronchoscopy with endobronchial biopsies. Baseline histopathology diagnoses included 91 cases (41.9%) with squamous metaplasia (Sm), 25 (11.5%) with squamous dysplasia (SD), 1 (0.5%) with in-situ carcinoma and 5 (2.3%) with invasive LC. Follow-up biopsies were obtained for 69 patients, and 16 (23.2%) patients demonstrated progression to a higher grade lesion. Regression models were used to evaluate the relationship between ILF and EPL. All the models were adjusted for age, gender and tobacco smoking. Results: Patients with FEV1% of mes greater risk of being diagnosed with an EPL [95% confidence interval: 1.93-10.80] and 8-fold greater risk of SD, compared to patients with FEV1% ≥80. COPD was associated with 2.7 and 4.8 times greater risk of Sm and SD, respectively. The mean time to progression to a higher-grade lesion was shorter in COPD patients compared to patients without COPD (27 versus 50 months, p = 0.02). Conclusion: Our results indicate that ILF may be a predictor of prevalence and progression of EPLs among patients at high risk of LC. Therefore, spirometry can be a complementary pre-screening tool for identifying patients with EPL who need more intense LC surveillance.

关键词： COPD Lung Cancer Premalignant Lesions Dysplasia Pulmonary Function Test Spirometry

Geomagnetic field absenee reduces adult body weight of a migratory insect by disrupt!ng feeding behavior and appetite regulation

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Insect Science 2021年第1期28卷 251-260页

作者： Gui-Jun Wan Shou-Lin Jiang ming Zhang Jing-Yu Zhao Ying-Chao Zhang Wei-Dong Pan gregory A.Sword Fa-Jun Chen Department of Entomology Nanjing Agricultural UniversityNanjingChina Beijing Key Laboratory of Bioelectromagetics Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina Department of Entomology Texas A&M UniversityCollege StationTXU.S.A.

The geomagnetic field(GmF)is well documented for its essential role as a cue used in animal orientation or *** evidence indicates that the absence of GmF(mimicked by the near-zero magnetic field,NZmF)can trigger stress-like responses such as reduced body weight,as we have previously shown in the brown planthopper,Nilaparvata *** this study,we found that consistent with the significantly decreased body weight of newly emerged female(—14.67%)and male(—13.17%)adult ***,the duration of the phloem ingestion feeding waveform was significantly reduced by 32.02%in 5th instar nymphs reared under the NZmF versus ***,5th instar nymphs that exhibited reduced feeding had significantly higher glucose levels(+16.98%and+20.05%;24 h and 48 h after molting),which are associated with food aversion,and expression patterns of their appetite-related neuropeptide genes(neuropeptide F,dow regulated overall;short neuropeptide F,dowregulated overall;adipokinetic hormone up-regulated overall;and adipokinetic hormone receptor,down-regulated overall)were also altered under the absence of GmF in a manner consistent with diminishing ***,the expressions of the potential magnetosensor croptochromes(Crys)were found significantly altered under the absence of GmF,indicating the likely upstream signaling of the Cry-mediated magnetoreception *** findings support the hypothesis that strong changes in GmF intensity can reduce adult body weight through affecting insect feeding behavior and underlying regulatory processes including appetite *** results highlight that GmF could be necessary for the maintenanee of energy homeostasis in insects.

关键词： appetite body weight feeding behavior geomagnetic field magnetoreception Nilaparvata lugens

Androgen receptor deficiency in monocytes/ macrophages does not alter adiposity or glucose homeostasis in male mice

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Asian Journal of Andrology 2018年第3期20卷 276-283页

作者： Katya B Rubinow Barbara Houston Shari Wang Leela Goodspeed Kayoko Ogimoto gregory J morton Christopher mcCarty Robert E Braun Stephanie T Page Division of metabolism Endocrinology and Nutrition Department of Medicine University of Washington School of Medicine Seattle WA 98195 USA Jackson Laboratory Bar Harbor ME 04609 USA

Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor （AR） is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. male mice bearing a cell-specific knockout of the AR in monocytes/macrophages （m-ARKO） were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type （WT） and m-ARKO mice （12-22 weeks of age, n = 12 per group） were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake （3.0 ± 0.5 g per day for WT mice vs 2.8 ± 0.4 g per day for m-ARKO mice） or total energy expenditure （0.6 ± 0.1 Kcal h-1 for WT mice vs 0.5 ± 0.1 Kcal h-1 for m-ARKO mice） were evident between groups during high-fat feeding. Liver weight was greater in m-ARKO than that in WT mice （1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02）. Finally, m-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to WT mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.

关键词： androgen receptor knockout mice macrophages male hypogonadism metabolic syndrome

Universal frequency engineering tool for microcavity nonlinear optics:multiple selective mode splitting of whispering-gallery resonances

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Photonics Research 2020年第11期8卷 1676-1686页

作者： Xiyuan Lu Ashutosh Rao gregory moille Daron A.Westly Kartik Srinivasan microsystems and Nanotechnology Division Physical Measurement LaboratoryNational Institute of Standards and TechnologyGaithersburgM aryland 20899USA Institute for Research in Electronics and Applied Physics and m aryland NanoCenter University of MarylandCollege ParkMaryland 20742USA Department of Chemistry and Biochemistry University of MarylandCollege ParkMaryland 20742USA Joint Quantum Institute NIST/University of MarylandCollege ParkMaryland 20742USA

Whispering-gallery microcavities have been used to realize a variety of efficient parametric nonlinear optical processes through the enhanced light–matter interaction brought about by supporting multiple high quality factor and small modal volume *** to such studies is the ability to control the relative frequencies of the cavity modes,so that frequency matching is achieved to satisfy energy *** this is done by tailoring the resonator cross *** so modifies the frequencies of all of the cavity modes,that is,the global dispersion profile,which may be undesired,for example,in introducing competing nonlinear ***,we demonstrate a frequency engineering tool,termed multiple selective mode splitting(mSmS),that is independent of the global dispersion and instead allows targeted and independent control of the frequencies of multiple cavity *** particular,we show controllable frequency shifts up to 0.8 nm,independent control of the splitting of up to five cavity modes with optical quality factors≳10^5,and strongly suppressed frequency shifts for untargeted *** mSmS technique can be broadly applied to a wide variety of nonlinear optical processes across different material platforms and can be used to both selectively enhance processes of interest and suppress competing unwanted processes.

关键词： resonator nonlinear splitting