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Mercury photoreduction and photooxidation in lakes：Effects of filtration and dissolved organic carbon concentration

Journal of Environmental Sciences 2018年第6期30卷 151-159页

作者： nelson J.O’Driscoll Emma Vost Erin mann Sara Klapstein Robert Tordon Matthew Lukeman Department of Earth & Environmental Science Acadia University Wolfville B4P 2R6 Nova Scotia Canada Environment Canada Dartmouth Nova Scotia Canada Department of Chemistry Acadia University Wolfville B4P 2R6 Nova Scotia Canada

Mercury is a globally distributed, environmental contaminant. Quantifying the retention and loss of mercury is integral for predicting mercury-sensitive ecosystems. There is little information on how dissolved organic carbon（DOC） concentrations and particulates affect mercury photoreaction kinetics in freshwater lakes. To address this knowledge gap,samples were collected from ten lakes in Kejimkujik national Park, nova Scotia（DOC： 2.6–15.4 mg/L）. Filtered（0.2 μm） and unfiltered samples were analysed for gross photoreduction, gross photooxidation, and net reduction rates of mercury using pseudo first-order curves. Unfiltered samples had higher concentrations（p = 0.04） of photoreducible divalent mercury（Hg（II）RED）（mean of 754 ± 253 pg/L） than filtered samples（mean of 482 ± 206 pg/L）;however, gross photoreduction and photooxidation rate constants were not significantly different in filtered or unfiltered samples in early summer. DOC was not significantly related to gross photoreduction rate constants in filtered（R2= 0.43; p = 0.08） and unfiltered（R2= 0.02; p = 0.71） samples; DOC was also not significantly related to gross photooxidation rate constants in filtered or unfiltered samples. However, DOC was significantly negatively related with Hg（Ⅱ）RED in unfiltered（R2= 0.53; p = 0.04）, but not in filtered samples（R2= 0.04;p = 0.60）. These trends indicate that DOC is a factor in determining dissolved mercury photoreduction rates and particles partially control available Hg（Ⅱ）RED in lake water. This research also demonstrates that within these lakes gross photoreduction and photooxidation processes are close to being in balance. Changes to catchment inputs of particulate matter and DOC may alter mercury retention in these lakes and could partially explain observed increases of mercury accumulation in biota.

关键词： Mercury Photoreduction Photooxidation Dissolved organic carbon(DOC) Particulates Kejimkujik national Park

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A Second Main Theorem on P^n for difference operator

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Science China Mathematics 2009年第12期52卷 2751-2758页

作者： WOnG Pit-mann LAW Hiu-Fai WOnG Philip P.W. Department of Mathematics University of Notre Dame Department of Mathematics University of Hong Kong

The main result of this article is an extension of the Second Main Theorem,of Halburd and Korhonen,for meromorphic functions of finite *** result replaces the counting function of the ramification divisor nramf(r)in the classical Second Main Theorem by the counting function of a finite difference divisor npair(r).In this article,the Second Main Theorem of Halburd and Korhonen is extended to the case of holomorphic maps into Pn of finite order.

关键词： finite difference Second Main Theorem finite order ramification

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Testes extracts inhibit heart contractions in females of the blood-feeding insect, Rhodnius prolixus

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Insect Science 2010年第4期17卷 386-392页

作者： Jocelyn D. Martens R. gary Chiang Biology Department Redeemer University College Ancaster Ontario Canada

Myogenic contractions of the heart of the female blood-feeding insect, Rhodnius prolixus （Stal）, are inhibited by crude extracts of testes applied directly to isolated dorsal vessels. Dorsal vessels were observed with a stereo microscope and heart beats timed with a stopwatch. In normal Rhodnius saline, hearts contract at 14.8 4- 7.1 beats per minute （n = 45）. Crude extracts of the testes and the two male reproductive accessory organs （the opaque and transparent accessory glands） were prepared from previously frozen tissue by homogenizing 5-20 glands in a small glass homogenizer containing Rhodnius saline, centrifuging for 5 rain at 2 000 g, and collecting the supernatant. Testes extract as low as 1.0 glands per mL inhibit contractions whereas crude extracts of the opaque or transparent accessory glands have no consistent effect. We refer to this cardiac inhibitor as rhodtestolin （Rhodnius testis inhibitory factor）, and discuss its possible effects on the female during copulation.

关键词： cardiac inhibition copulation heart beat Rhodnius rhodtestolin testis

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Age predicts the absence of caloric-induced vertigo

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Journal of Otology 2018年第1期13卷 5-9页

作者： gary P.Jacobson Erin G.Piker Sarah L.Grantham Lauren n.English Department of Hearing and Speech Sciences Divisions of Audiology and Vestibular Sciences Vanderbilt University Medical Center Nashville TN USA Department of Communication Sciences and Disorders James Madison University Harrisonburg VA USA

Introduction: The absence of vertigo during the caloric test, despite a robust response, has been suggested to represent a central vestibular system phenomenon. The purpose of this investigation was to determine the prevalence of absent caloric-induced vertigo perception in an unselected group of patients and to assess possible predicting ***: Prospective investigation of 92 unselected patients who underwent caloric testing. Inclusion criteria were that each patient generate a maximum slow phase velocity(maxSPV) > 15 deg/sec and a caloric asymmetry of≤10%. Following the caloric, patients were asked, "Did you have any sensation of motion?"Results: Results showed 75% of patients reported motion with a mean age of 56.51 years compared to a mean age of 66.55 in the 25% of patients reporting an absence of motion. A logistic regression was performed and the overall model was statistically significant accounting for 29% of the variance in caloric perception. The significant predictor variables were patient age and maxSPV of the caloric response. The effect size for both variables was small with an odds ratio of.9 for maxSPV and 1.06 for ***: The current investigation showed that both age and maxSPV of the caloric response were significant predictors of vertigo perception during the caloric exam. However, the association between age and caloric perception is not conclusive. Although there is evidence to suggest that these findings represent age-related changes in the central processing of vestibular system stimulation, there are additional unmeasured factors that influence the perception of caloric-induced vertigo.

关键词： Vestibular Vertigo Central processing Caloric test Aging

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Burn recidivism:a 10-year retrospective study characterizing patients with repeated burn injuries at a large tertiary referral burn center in the United States

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Burns & Trauma 2019年第1期7卷 75-84页

作者： Sarah L.Laughon Bradley n.Gaynes Lori P.Chrisco Samuel W.Jones Felicia n.Williams Bruce A.Cairns gary J.Gala Department of Psychiatry 101 Manning DriveCB#7160Chapel HillNC 27599-7160USA Department of Surgery 4001 Burnett-Womack BuildingCB#7050Chapel HillNC 27599-7050USA north Carolina Jaycee Burn Center 101 Manning DriveCB#7206Chapel HillNC 27599-7600USA

Background:Psychiatric and substance use disorders are common among trauma and burn patients and are known risk factors for repeat episodes of trauma,known as trauma *** epidemiology of burn recidivism,specifically,has not been *** study aimed to characterize cases of burn recidivism at a large US tertiary care burn center and compare burn recidivists(RCs)with non-recidivists(nRCs).Methods:A 10-year retrospective descriptive cohort study of adult burn patients admitted to the north Carolina Jaycee Burn Center was conducted using data from an electronic burn registry and the medical *** variables were reported using medians and interquartile ranges(IQR).Chi-square and Wilcoxon-mann-Whitney tests were used to compare demographic,burn,and hospitalization characteristics between nRCs and ***:A total of 7134 burn patients were admitted,among which 51(0.7%)were RCs and accounted for 129(1.8%)*** the 51 RCs,37 had two burn injuries each,totaling 74 admissions as a group,while the remaining 14 RCs had between three and eight burn injuries each,totaling 55 admissions as a *** to nRCs,RCs were younger(median age 36 years vs.42 years,p=0.02)and more likely to be white(75%vs.60%,p=0.03),uninsured(45%vs.30%,p=0.02),have chemical burns(16%vs.5%,pnd have burns that were≤10%total body surface area(89%vs.76%,p=0.001).The mortality rate for RCs *** did not differ(0%vs.1.2%,p=0.41).Psychiatric and substance use disorders were approximately five times greater among RCs compared to nRCs(75%vs.15%,pn total hospital charges per patient were nearly three times higher for RCs ***($85,736 vs.$32,023,pnclusions:Distinct from trauma recidivism,burn recidivism is not associated with more severe injury or increased *** to trauma recidivists,but to a greater extent,burn RCs have high rates of comorbid psychiatric and medical conditions that contribute to increased health care u

关键词： Burn recidivism Consult psychiatry Substance use disorder Repeat burn injury

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Triolein emulsion infusion into the hepatic artery increases vascular permeability to doxorubicin in rabbit liver

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World Journal of Gastroenterology 2021年第2期27卷 152-161页

作者： Yong-Woo Kim Hak Jin Kim Byung mann Cho Seon Hee Choi Department of Radiology Research Institute for Convergence of Biomedical Science and TechnologyPusan National University Yangsan HospitalPusan National University College of MedicineYangsan 50612South Korea Department of Radiology Biomedical Research InstitutePusan National University HospitalPusan National University College of MedicineBusan 49241South Korea Preventive Medicine and Occupational Medicine Pusan National University School of MedicineYangsan 50612South Korea Department of Radiology Pusan National UniversityBusan 49241South Korea

BACKGROUnD The infusion of triolein emulsion(TE)induced increased vascular permeability and a negligible and temporary decrease in liver function without specific histopathological *** To assess changes in doxorubicin concentration according to the percentage of TE infused via a hepatic artery to study the vascular permeability in the rabbit *** Thirty-nine healthy rabbits were divided into five groups according to the concentration of emulsified triolein infused into the hepatic arteries:Group 0,saline infusion(control group,n=5);group 1,0.3%TE(n=13);group 2,0.6%TE(n=6);group 3,0.9%TE(n=8);and group 4,1.5%TE(n=6).Doxorubicin(2.4 mg/kg)was infused immediately after TE injection via the hepatic *** 2 h,the livers were harvested,and doxorubicin concentrations were calculated *** doxorubicin concentrations were compared between TE groups and the control group,and the optimal concentrations within the TE groups were *** analysis was performed using the nonparametric mann-Whitney U test and Kruskal-Wallis test.Pnsidered statistically *** In the liver,doxorubicin concentrations were 2.06,2.07,2.16 and 1.66 times higher in groups 1 through 4,respectively,and significantly higher in the TE groups than in the control group(all Pno significant differences in the mean doxorubicin concentrations between the four TE groups(P=0.642).In the lungs,the mean doxorubicin concentrations were not significantly different between the control and TE groups(P>0.05).COnCLUSIOn TE infusion into the hepatic arteries significantly increased the doxorubicin concentration approximately twofold but was not different between the TE *** findings suggest that TE infusion might be a useful adjuvant treatment of liver cancers.

关键词： Triolein emulsion Liver tumor Chemotherapy Drug delivery Vascular permeability Dexorubicin

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Can Ebola virus become endemic in the human population？

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Protein & Cell 2016年第1期7卷 4-6页

作者： gary Wong George F. Gao Xiangguo Qiu Special Pathogens Program National Microbiology Laboratory Public Health Agency of Canada Winnipeg MB CanadaDepartment of Medical Microbiology University of Manitoba Winnipeg MB Canada Department of Medical Microbiology University of Manitoba Winnipeg MB Canada CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of SciencesBeijing 100101 China national Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100052 China Officeof Director-General Chinese Center for Disease Control and Prevention Beijing 102206 China

The 2014-15 Ebola virus reported during March 2014 Guinea. has shown itself to （EBOV） outbreak, originally n the Western African nation of be resistant to traditional con- tainment methods, with over 28,000 infections and 11,000 deaths over 18 months. Recently, news that a Scottish nurse had relapsed to EBOV disease with neurological symptoms at 10 months after recovery have astonished experts. The prolonged nature of the outbreak has led to questions whether EBOV can become endemic in the human popula- tion, an undesirable outcome due to the large amount of resources required to keep this virus under control. In this commentary, we discuss aspects EBOV disease with those caused by pathogens considered endemic in humans, as well as factors which may contribute to sustained EBOV transmission in humans.

关键词： High Case Fatality Rate EBOV Infection Severe Hemorrhagic Fever Minor Public Health EBOV Outbreak

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Validation of a radioimmunoassay-based fecal corticosteroid assay for Richardson＇s ground squirrels Urocitellus richardsonii and behavioural correlates of stress

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Current Zoology 2014年第5期60卷 591-601页

作者： James F. HARE Calen R RYAn Chris EnRIGHT Laura E. GARDInER Lindsay J SKYnER Charlene n. BERKVEnS W. gary AnDERSOn Department of Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Assiniboine Park Zoo Winnipeg MB Canada R3R 2N7 Present Address: School of Applied Science Bay of Plenty Polytechnic Tauranga 3112 New Zealand

We validated a radioimmunoassay-based method quantifying fecal glucocorticoid metabolites （FGMs） from captive male and female Richardson＇s ground squirrels Urocitellus richardsonii. Blood samples were drawn to explore the correlation between plasma cortisol and FGM concentrations. We also injected groups of squirrels with normal saline （CTL; control）, adre- nocorticotropic hormone （ACTH; stimulating adrenal activity）, or dexamethasone （DEX; suppressing adrenal activity）. Potential correlations between stress and behaviour were explored through quantification of fecal pellet production and the intervention necessary to elicit defecation, as well as the behaviour of subjects in the context of handling. Changes in plasma cortisol concen- tration between capture （baseline）, and following handling （stress-induced） were also quantified for free-living squirrels. While glucocorticoid concentrations recovered from feces during our captive-animal study were not well correlated with plasma eortisol concentrations, and uncorrelated with defecation or behaviour, FGM concentrations did reflect the activation of the hypothalamic- pituitary-adrenal （HPA） axis. FGM concentrations increased significantly during initial captivity, but declined to baseline level as individuals acclimated to the novel environment. Injection of subjects with ACTH increased FGMs above baseline, confirming activation of the HPA axis. Plasma cortisol concentrations increased significantly with induced stress, indicating that capture and handling activated the glucocorticoid stress response even among previously handled, free-living subjects. Our findings validate a non-invasive tool that will afford new insight into the physiological processes underlying social, reproductive and antipredator behaviour of Richardson＇s ground squirrels [Current Zoology 60 （5）： 591-601, 2014 ].

关键词： Stress Corticosteroids Fecal glucocorticoid metabolites Radioimmunoassay Richardson's ground squirrels

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Angle-Based Beamforming in mmWave Massive MIMO Systems with Low Feedback Overhead Using Multi-Pattern Codebooks

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China Communications 2019年第9期16卷 18-30页

作者： Yuyan Zhao Yanan Liu gary Boudreau Akram Bin Sediq Xianbin Wang Department of Electrical and Computer Engineering Western UniversityLondonON N6A 5B9Canada Ericsson Canada OttawaON K2K 2V6Canada

The integration of millimeter-wave(mmWave)communications and massive multiple input multiple output(MIMO)techniques is a promising solution to dramatically increase the 5G network *** using large antenna arrays,beamforming can be adopted to improve the 5G capacity by employing spatial domain *** a frequency division duplexing(FDD)based 5G mmWave MIMO system,beamforming operation requires timely downlink channel state information(CSI)***,the rapid channel variations caused by short wavelength of mmWave band,and the high-level feedback information required due to the large number of antennas in massive MIMO system lead to the significantly increased beamforming *** this paper,by exploiting the higher angular stability of such channels,we propose an angle-based beamforming scheme to reduce the feedback frequency and the number of feedback *** facilitate this approach users are initially selected to reduce the intra-zone interference before ***,location related feedback,which is not affected by the number of antennas,is adopted to reduce *** simulation results show that two proposed user selection algorithms can adapt to scenarios with diverse requirements,while the feedback overhead of proposed angle-based beamforming algorithm is sharply reduce compared with that of CSIbased beamforming algorithm.

关键词： angle-based beamforming codebook feedback reduction user selection

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Risk of conduction disturbances following different transcatheter aortic valve prostheses:the role of aortic valve calcifications

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Journal of Geriatric Cardiology 2022年第3期19卷 167-176页

作者： Francesco Pollari Ferdinand Vogt Irena Großmann Jill Marianowicz Marie Claes Steffen Pfeiffer Johannes Schwab Theodor Fischlein Cardiac Surgery Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Cardiology Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Radiology Klinikum NürnbergParacelsus Medical UniversityNurembergGermany

OBJECTIVES To assess the impact of prosthesis choice and aortic valve calcifications on the occurrence of conduction disturb-ances after transcatheter aortic valve implantation(TAVI).METHODS We retrospectively analyzed the preoperative clinical characteristics,electrocardiograms,contrast-enhanced mul-tidetector computed tomography scans and procedural strategies of patients who underwent TAVI in our center between January 2012 and June *** of calcium volume was performed for each aortic cusp above(aortic valve)and below(left ventricular outflow tract,LVOT)the basal *** analysis was performed to evaluate risk factors for the onset of new bundle branch block(BBB),transient and permanent atrioventricular block(tAVB,pAVB).RESULTS A total of 569 patients were included in the *** different prostheses were implanted(Edwards Sapien XT,n=162;Edwards Sapien 3,n=240;Medtronic CoreValve,n=27;Medtronic CoreValve Evolut R,n=21;Symetis Acurate,n=56;Sy-metis Acurate neo,n=63).The logistic regression analysis for BBB showed association with baseline left anterior *** logistic regression for tAVB,found the prior valvuloplasty and the balloon post-dilatation associated with the *** left and right BBB,degree of oversizing,and LVOT calcification beneath the non-coronary cusp were associated with *** the prosthesis model,nor the use of a self-expandable prosthesis showed statistical significance with the above-men-tioned outcomes on univariate *** LVOT calcification beneath the non-coronary cusp,baseline left anterior hemiblock,right BBB,balloon post-dilatation,prior valvuloplasty and oversizing are independently associated with postprocedural conduction disturbances after *** of a self-expandable prosthesis may show a lower incidence of AVB,if applied in lower calcified aortic valves.

关键词： aortic balloon conduction

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