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Total organic halogen(TOX) in human urine: A halogen-specific method for human exposure studies

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Journal of Environmental Sciences 2017年第8期29卷 285-295页

作者： Susana Y.Kimura Weiwei Zheng Taylor N.Hipp Joshua M.Allen Susan d.Richardson department of Chemistry and Biochemistry University of South Carolina Key Laboratory of Public Health Safety Ministry of Education Department of Environmental Health School of Public Health Fudan University

disinfection by-products（dBPs） are a complex mixture of compounds unintentionally formed as a result of disinfection processes used to treat drinking water. Effects of long-term exposure to dBPs are mostly unknown and were the subject of recent epidemiological studies. However,most bioanalytical methods focus on a select few dBPs. In this study, a new comprehensive bioanalytical method has been developed that can quantify mixtures of organic halogenated compounds, including dBPs, in human urine as total organic chlorine（TOCl）, total organic bromine（TOBr）, and total organic iodine（TOI）. The optimized method consists of urine dilution, adsorption to activated carbon, pyrolysis of activated carbon, absorption of gases in an aqueous solution, and halide analysis with ion chromatography and inductively coupled plasma-mass spectrometry. Spike recoveries for TOCl, TOBr, and TOI measurements ranged between 78% and 99%. Average TOCl, TOBr, and TOI concentrations in five urine samples from volunteers who consumed tap water were 1850, 82, and 21.0 μg/L as X^-, *** who consumed spring water（control） had TOCl, TOBr, and TOI average concentrations in urine of 1090, 88, and 10.3 μg/L as X^-, respectively. TOCl and TOI in the urine samples from tap water consumers were higher than the control. However, TOBr was slightly lower in tap water urine samples compared to mineral water urine samples, indicating other sources of environmental exposure other than drinking water. A larger sample population that consumes tap water from different cities and mineral water is needed to determine TOCl, TOBr, and TOI exposure from drinking water.

关键词： Adsorbable organic halogen(AOX) Total organic halogen(TOX) disinfection by-products(dBPs) Total organic chlorine(TOCl) Total organic bromine(TOBr) Total organic iodine(TOI) Urine drinking water

Challenges in the implementation of food safety and quality assurance systems in small-scale fisheries

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Food Quality and Safety 2023年第1期7卷 178-186页

作者： Esther GarridoGamarro Cecilie Smith Svanevik Anne-Katrine Lundebye Monica Sanden Enrica d'Agostino Marian Kjellevold Lauren Pincus Johannes Pucher Fisheries and Aquaculture division Food and Agriculture Organization of the United NationsViale delle Terme di CaracallaRomeItaly Institute of Marine Research BergenNorway WorldFish Jalan Batu MaungBatu MaungPenangMalaysia German Federal Institute for Risk Assessment Department Experimental Toxicology and ZEBETBerlinGermany Shared first authorship

Ninety percent of the world’s fishers are directly involved in small-scale fisheries(SSFs),and many food safety and quality issues along the food value chains may be both irreversible and *** safe,high-quality aquatic products are key to sustaining life,promoting good health,and avoiding adverse health *** This paper aimed to highlight factors preventing the implementation of safety and quality assurance systems in SSFs by analysing the results from surveys on the implementation of Article 11 of the Food and Agriculture Organization of the United Nations(FAO)Code of Conduct for Responsible Fisheries(2017,2019,and 2022).Materials and methods The analysis considered responses to 15 closed-ended questions on food safety and quality obtained from 143 FAO Members and the European Union,and 87 open-ended replies addressing challenges in *** The major factors preventing the implementation of the Code’s food safety and quality provisions were lack of sanitation and monitoring programmes,lack of infrastructure(particularly refrigeration facilities)lack of technical capacities and limited management of food safety risks along the value *** and quality assurance efforts were focused on international markets,resulting in less attention being paid to domestic markets where a high degree of informality was *** Improved implementation of safety and quality assurance systems will lead to safer food with higher nutritional quality,extended shelf-life and reduced post-harvest *** awareness of food safety issues in SSFs is a prerequisite for achieving several of the UN Sustainable development Goals.

关键词： Food security policy monitoring legislation value chain domestic market international trade

Ototoxic destruction by co-administration of kanamycin and ethacrynic acid in rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第10期12卷 853-861页

作者： Hong LIU da-lian d1NG Hai-yan JIANG Xue-wen WU Richard SALVI Hong SUN Center for Hearing and deafness University at Buffalo State University of New York New York 14214 USA department of Otolaryngology the Third Xiangya Hospital of Central South University Changsha 410013 China department of Otolaryngology Xiangya Hospital of Central South University Changsha 410008 China

It is well known that ethacrynic acid (EA) can potentiate the ototoxicity of aminoglycoside antibiotics (AmAn) such as kanamycin (KM),if they were applied at the same ***,to create the model of EA-KMinduced cochlear lesion in rats,adult rats received a single injection of EA (75 mg/kg,intravenous injection),or followed immediately by KM (500 mg/kg,intramuscular injection).The hearing function was assessed by auditory brainstem response (ABR) measurement in response to click and/or tone bursts at 4,8,12,16,20,24,and 32 *** static microcirculation status in the stria vascularis after a single EA injection was evaluated with eosin *** pathological changes in cochlear and vestibular hair cells were also quantified after co-administration of EA and *** a single EA injection,blood flow in vessels supplying the stria vascularis rapidly ***,the blood supply to the cochlear lateral wall partially recovered 5 h after EA *** changes in ABR were basically parallel to the microcirculation changes in stria vascularis after single EA ***,disposable co-administration of EA and KM resulted in a permanent hearing loss and severe damage to the cochlear hair cells,but spared the vestibular hair *** the cochlear lateral wall is the important part of the blood-cochlea barrier,EA-induced anoxic damage to the epithelium of stria vascularis may enhance the entry of KM to the ***,experimental animal model of selective cochlear damage with normal vestibular systems can be reliably created through co-administration of EA and KM.

关键词： Ototoxicity Ethacrynic acid Kanamycin Rat Blood-cochlea barrier

discovery of Japalura chapaensis Bourret,1937(Reptilia:Squamata:Agamidae)from Southeast Yunnan Province,China

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Zoological Research 2018年第2期39卷 105-113页

作者： Kai Wang Ke Jiang Yu-Fan Wang Nikolay A.Poyarkov Jr. Jing Che Cameron d.Siler Sam Noble Oklahoma Museum of Natural History & department of Biology University of Oklahoma Kunming Institute of Zoology Chinese Academy of Sciences Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Zhejiang Forest Resource Monitoring Center department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University

due to a paucity of surveys in northern Indochina and lack of international collaborations among neighboring countries, recognized distributional ranges for many amphibian and reptile species end at the political borders for some countries, despite seemingly continuous suitable habitat spanning the region. Combining both morphological and genetic data, we report the first discovery of Japalura chapaensis, a rare agamid lizard believed previously to be endemic to northern Vietnam only, along the border region of southeastern Yunnan Province,China. To facilitate future research on the genus Japalura sensu lato in Indochina, we provide detailed descriptions of additional specimens of this rare species, including the first description of coloration in life and an expanded diagnosis, and discuss the species boundary of J. chapaensis with respect to its congeners.

关键词： draconinae Indochina Morphological Variation New record Range extension Systematics Taxonomy

Experimental observations of nonlinear effects of the Lamb waves

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Chinese Journal of Acoustics 2004年第3期23卷 226-243页

作者： dENGMingxi d.C.Price d.A.Scott LogisticsEngineeringUniversityChongqing400016 CSIROTelecommunicationandIndustrialPhysicsNSW Australia

The experimental observations of nonlinear effects of the primary Lamb waves have been reported. Firstly, the brief descriptions have been made for the nonlinear acoustic measurement system developed by Ritec. The detailed considerations for the acoustic experiment system established for observing of the nonlinear effects of the primary Lamb waves have been carried out. Especially, the analysis focuses on the time-domain responses of second harmonics of the primary Lame waves by employing a straightforward model. Based on the existence conditions of strong nonlinearity of the primary Lamb waves, the wedge transducers are designed to generate and detect the primary and secondary waves on the surface of an aluminum sheet. For the different distances between the transmitting and receiving wedge transducers, the amplitudes of the primary waves and the second harmonics on the sheet surface have been measured within a specified frequency range. In the immediate vicinity of the driving frequency, where the primary and the double frequency Lamb waves have the same phase velocities, the quantitative relations of second-harmonic amplitudes with the propagation distance have been analyzed. It is experimentally verified that the second harmonics of the primary Lamb waves do have a cumulative growth effect along with the propagation distance.

关键词： Experimental observations of nonlinear effects of the Lamb waves MHz

X射线三晶衍射研究YBa_2Cu_3O_y超导薄膜

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物理学报 1993年第9期42卷 1479-1484页

作者：李超荣麦振洪 Р.d.НАТТОN С.Н.du 中国科学院物理研究所北京100080 department of Physics University of EdinburghU.K.

应用X射线三晶衍射对LaAlO_3衬底上生长的YBa_2Cu_3O_y薄膜中的应力水平、存在的主要缺陷,以及薄膜与衬底的失配和取向关系等进行了研究。结果表明,薄膜在衬底上几乎完全松弛,应力很小,薄膜存在较严重的晶格取向差缺陷,这是影响薄膜晶... 详细信息

应用X射线三晶衍射对LaAlO_3衬底上生长的YBa_2Cu_3O_y薄膜中的应力水平、存在的主要缺陷,以及薄膜与衬底的失配和取向关系等进行了研究。结果表明,薄膜在衬底上几乎完全松弛,应力很小,薄膜存在较严重的晶格取向差缺陷,这是影响薄膜晶体结构完整性的主要因素。此外,衬底与薄膜在垂直于表面和平行于表面方向都存在取向差。

关键词：超导膜薄膜 X射线衍射 YBCO

The effect of caloric restriction on genetical pathways

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Food Science and Human Wellness 2023年第5期12卷 1450-1457页

作者： Mustafa Fevzi Karagöz A.Gülçin Sağdıçoğlu Celep Faculty of Health Sciences Department of Nutrition and DieteticsGazi UniversityÇankaya 06490Turkey

Energy restriction is defined as reducing nutrient intake without dragging the organism into malnutrition. Energy restriction is preferred because it is a non-genetic intervention that increases life expectancy. Nicotinamide adenine dinucleotide(NAd~+)and adenosine monophosphate(AMP)levels, which are the indicators of intracellular energy deficiency, increase with energy restriction. The increase in NAd~+ level stimulates sirtuin(SIRT)enzymes, and the increase in AMP level stimulates AMP-activated protein kinase(AMPK). Various mechanisms are regulated by stimulating these enzymes. By Forkhead box O(FoxO)transcription factors, the ability of resistance to oxidative stress increases, and antioxidant genes, dNA repair, and autophagy genes are stimulated. Apoptosis is induced by stimulation of the p53 protein, and tumor growth is suppressed by the disruption of aging cells. The suppression of phosphoinositide 3-kinase(PI3K)-/-Akt, and therefore mTOR signal stimulates autophagy and mitophagia, and cleanses damaged cells and organelles. Mitochondrial biogenesis is stimulated, antioxidant capacity increases, and inflammatory response decreases. Adipose tissue and lipid metabolism are regulated by the regulation of fatty acid synthesis and oxidation. As a consequence, the effects of caloric restriction on cellular metabolism are regulated through the genetic pathways.

关键词： Caloric restriction Energy restriction Sirtuin AMPK Mitochondrial biogenesis

Organic carbon content and carbon isotope variations across the Permo-Triassic boundary in the Gartnerkofel-1borehole, Carnic Alps, Austria

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Acta Geochimica 2018年第3期37卷 422-432页

作者： M.E.Brookfield W.S.Wolbach A.G.Stebbins I.Gilmour d.R.Roegge School for the Environment University of Massachusetts at Boston department of Chemistry De Paul University department of Physical Sciences Planetary and Space Sciences The Open University department of Chemistry Illinois Wesleyan University

The Gartnerkofel borehole is one of the most thoroughly studied and described Permo-Triassic sections in the world. detailed bulk organic carbon isotope studies show a negative base shift from-24% to-28% in the Latest Permian which latter value persists into the Earliest Triassic after which it decreases slightly to-26%. Two strongly negative peaks of [-38% in the Latest Permian and a lesser peak of-31% in the Early Triassic are too negative to be due to a greater proportion of more negative organic matter and must be due to very negative methane effects. The overall change to more negative values across the Bulla/Tesero boundary fits the relative rise in sea level for this transition based on the facies changes. A positive shift in organic carbon isotope values at the Late Permian Event Horizon may be due to an increase in land-derived organic detritus at this level—a feature shown by allTethyan Permo-Triassic boundary sections though these other sections do not have the same values. Carbonate carbon isotope trends are similar in all sections dropping by2–3 units across the Permo-Triassic boundary. Gartnerkofel carbonate oxygen values are surprisingly, considering the ubiquitous dolomitization, compatible with values elsewhere and indicate reasonable tropical temperatures of 60 °C in the Latest Permian sabkhas to 20–40 °C in the overlying marine transition beds. Increased landderived input at the Late Permian Event Horizon may be due to offshore transport by tsunamis whose deposits have been recognized in India at this level.

关键词： Organic Carbon Isotopes Permo-Triassic Gartnerkofel Austria

Hepatitis C virus antigens enzyme immunoassay for one-step diagnosis of hepatitis C virus coinfection in human immunodeficiency virus infected individuals

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World Journal of Hepatology 2019年第5期11卷 442-449页

作者： Ke-Qin Hu Wei Cui Susan d Rouster Kenneth E Sherman division of GI/Hepatology University of CaliforniaIrvineSchool of MedicineOrangeCA 92868United States division of digestive diseases University of Cincinnati College of MedicineCincinnatiOH 45267United States

BACKGROUNd Current diagnosis of hepatitis C virus(HCV)infection requires two sequential steps:testing for anti-HCV followed by HCV RNA PCR to confirm *** have developed a highly sensitive and specific HCV-antigens enzyme immunoassay(HCV-Ags EIA)for one-step diagnosis of viremic HCV *** To assess the clinical application of the HCV-Ags EIA in one-step diagnosis of viremic HCV infection in human immunodeficiency virus(HIV)-coinfected *** The study blindly tested HCV-Ags EIA for its performance in one-step diagnosing viremic HCV infection in 147 sera:10 without HCV or HIV infection;54 with viremic HCV monoinfection;38 with viremic HCV/HIV coinfection;and 45 with viremic HCV and non-viremic HIV *** Upon decoding,it was 100%accordance of HCV-Ags EIA to HCV infection status by HCV RNA PCR *** five sera with HCV infection,HCV RNA was as low as 50-59 IU/mL,and four out of five tested positive for HCV-Ags ***,it was also 100%accordance of HCV-Ags EIA to HCV infection status by HCV RNA PCR in 83 sera with HCV and HIV coinfection,regardless if HIV infection was active or *** The modified HCV-Ags EIA has a lower detection limit equivalent to serum HCV RNA levels of approximately 100 IU/*** is highly sensitive and specific in the setting of HIV coinfection,regardless of HIV infection status and Cd4 *** data support the clinical application of the HCV-Ags EIA in one-step diagnosis of HCV infection in HIV-infected individuals.

关键词： Hepatitis C virus Hepatitis C virus antigens Hepatitis C virus core antigen Hepatitis C virus diagnostic test diagnostic assay Enzyme immunoassay