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Maintenance of Species differences in Closely Related Tetraploid Parasitic Euphrasia (Orobanchaceae) on an Isolated Island

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Plant Communications 2020年第6期1卷 85-99页

作者： Hannes Becher Max R.Brown Gavin Powell Chris Metherell Nick J.Riddifordand alex d.twyford University of Edinburgh School of Biological SciencesInstitute of Evolutionary BiologyCharlotte Auerbach RoadEdinburgh EH93FLUK Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK Botanical Society of Britain and Ireland 4 High Firs CrescentHarpendenHertfordshire AL51NAUK Schoolton Fair IsleShetland ZE29JUUK

Polyploidy is pervasive in angiosperm evolution and plays important roles in adaptation and ***,polyploid groups are understudied due to complex sequence homology,challenging genome assembly,and taxonomic ***,we study adaptive divergence in taxonomically complex eyebrights(Euphrasia),where recent divergence,phenotypic plasticity,and hybridization blur species *** focus on three closely related tetraploid species with contrasting ecological preferences that are sympatric on Fair Isle,a small isolated island in the British *** a common garden experiment,we show a genetic component to the morphological differences present between these *** wholegenome sequencing and a novel k-mer approach we call“Tetmer”,we demonstrate that the species are of allopolyploid origin,with a sub-genome divergence of approximately 5%.Using2 million SNPs,we show sub-genome homology across species,with a very low sequence divergence characteristic of recent *** genetic variation is broadly structured by species,with clear divergence of Fair Isle heathland Euphrasia micrantha,while grassland Euphrasia arctica and coastal Euphrasia foulaensis are more closely ***,we show that tetraploid Euphrasia is a system of allopolyploids of postglacial species divergence,where adaptation to novel environments may be conferred by old variants rearranged into new genetic lineages.

关键词： incipient speciation k-mer spectrum allopolyploidy tetraploid divergence with gene flow taxonomic complexity

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Effectiveness of a fixed-depth sensor deployed from a buoy to estimate water-column cyanobacterial biomass depends on wind speed

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Journal of Environmental Sciences 2020年第7期32卷 23-29页

作者： Justin d.Chaffin douglas d.Kane alex Johnson F.T Stone Laboratory and Ohio Sea Grant the Ohio State UniversityOH 43456USA division of Natural Science Applied Scienceand MathematicsDefiance CollegeDefiance OHF.T Stone LaboratoryThe Ohio State University and Ohio Sea GrantOH 43456USA

Water quality sondes have the advantage of containing multiple sensors,extended deployment times,high temporal resolution,and telecommunication with stakeholder accessible data ***,sondes that are part of buoy deployments often suffer from typically being fixed at one *** water treatment plants are interested in water quality at a depth of the water intake and other stakeholders(*** and swimmers)are interested in the surface,we examined whether a fixed depth of approximately 1 m could cause over-or under-estimation of cyanobacterial *** sampled the vertical distribution of cyanobacteria adjacent to a water quality sonde buoy in the western basin of Lake Erie during the summers of 2015–2017.A comparison of buoy cyanobacteria RFU(Relative Fluorescence Unit)at 1 m to cyanobacteria chlorophyll a(chla)measured throughout the water column showed occurrences when the buoy both under and overestimated the cyanobacteria chl a at specific *** differences between buoy measurements and at-depth grab samples occurred during low wind speeds(ds allowed cyanobacteria to accumulate at the surface above the buoy’s *** wind speeds(>4.5 m/sec)resulted in better agreement between the buoy and at-depth *** wind speeds 12 hr before sample collection decreased the difference between the buoy and at-depth samples for high wind speeds but not low *** suggest that sondes should be placed at a depth of interest for the appropriate stakeholder group or deploy sondes with the ability to sample at various depths.

关键词： Buoyancy Harmful algal bloom Lake Erie Microcystis Water quality

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A transition from a large open pit into a novel “macroblock variant” block caving geometry at Chuquicamata mine, Codelco Chile

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 549-561页

作者： German Flores alex Catalan Newcrest Mining Ltd. Melbourne3004Australia Codelco Chile Santiago8320000Chile

With a history of more than 100 years, Chuquicamata has become one of the largest open pits in the world. Its current depth of 1100 m, length of 4500 m and width of 3000 m, resulting in haulage distances of over 11,000 m from pit bottom to the processing plant or waste dumps, with waste/ore ratio greater than 4 and much lower grades, are effectively determining its profitable limit by the end of this decade. Currently, there are over 4300 Mt of geological resources containing 0.7% of copper and 340 ppm (1 ppm = 1 g/t) of molybdenum below the final pit shell. The corresponding orebody geometry is 3000 m northsouth, 300-800 m eastwest and the drilling campaign suggested the existence of more than 900 m of mineable ore from the final pit bottom. This is in spite of the fact that the Chuquicamata orebody is still open at depth. The business case to continue with the mining of the Chuquicamata orebody is to change from the current large open pit to a novel macroblock variant block caving geometry. This requires a production rate of 140,000 t/d (50 Mt per annum), with a continuous material handling system to achieve the 7-year ramp-up to full production. The resolution of a number of known technical, operational and logistical challenges outside current industry practises which Chuquicamata will face over its projected 40-year mine life is therefore essential. These challenges include simultaneous operations of open pit and underground macroblocks and from the initial lift to the second lift, rapid ramp-up and optimum sequencing of the planned macroblocks, early dilution from the west fault and late dilution from potential slope failures, and the potential for major operational hazards. An equally important issue to be addressed is cultural given that the mining history in the northern region of Chile, which includes Chuquicamata, is predominantly open pit. This paper presents a synopsis of the main challenges that the Chuquicamata underground project will face in order t

关键词： Macroblock variant Block caving Cave propagation Early and late dilutions Intensive preconditioning Rib pillar West fault Ore buffer

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Multi-frequency dielectrophoretic characterization of single cells

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Microsystems & Nanoengineering 2018年第1期4卷 156-164页

作者： alex Jaffe Joel Voldman department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMAUSA

We explore the use of dielectrophoresis to discern the electrical properties of single cells by observing them at multiple *** first simulate experimental conditions to show that as we increase the number of measured frequencies,we are able to better discriminate among different ***,we use the simulation to find the optimal number and value of frequencies to use to best discriminate among different cells in *** then fabricate a microfluidic device,calibrate it with polystyrene beads,and characterize it with BA/F3 *** this device,we test three different activation levels of HL60 cells treated with cytochalasin d using the optimal frequency sequence obtained in simulation to determine the differences in discrimination abilities depending on the number of frequencies *** quantify the discrimination abilities of the optimal one,two,and three frequencies by minimizing 0-1 loss.

关键词： optimal beads characterization

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Increased salt sensitivity induced by sensory denervation: role of superoxide

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Acta Pharmacologica Sinica 2004年第12期25卷 60-66页

作者： alex F CHEN,donna H WANG department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA

AIM: To test the hypothesis that production of superoxide in mesenteric resistance arteries is increased and con- tributes to the development of hypertension induced by sensory denervation plus high salt intake. METHOdS: Newborn Wistar rats were given capsaicin 50 mg/kg sc on the 1st and 2nd d of life. After weaning, male rats were grouped as follows and treated for 3 weeks with: capsaicin pretreatment plus normal sodium diet (0.5 %, CAP-NS), CAP plus high sodium diet (4 %, CAP-HS), control plus NS (CON-NS), or CON-HS. Both tail-cuff systolic blood pressure and mean arterial pressure (MAP) were measured in each of the groups. Western blot analysis was used for measurement of manganese superoxide dismutase (MnSOd) and endothelial nitric oxide synthase (eNOS) in the mesenteric resistance arteries. Lucigenin chemiluminescence assay was used for superoxide production in the mesenteric resistance arteries. The Griess method was used for measurement of nitrite/nitrate levels in plasma. RESULTS: Both tail-cuff pressure and MAP were higher in CAP-HS compared with CAP-NS, CON-HS, and CON- NS rats (Pd and eNOS in the mesenteric resistance arteries were increased in CAP-HS compared with CAP-NS, CON-HS, and CON-NS (Pdifferent among 4 groups. Acute iv administration of tempol, a membrane-permeable superoxide scavenger, de- creased MAP in both CAP-HS and CON-HS when compared with their respective controls. However, the de- creases of MAP between these two groups were not different. Chronic treatment with tempol failed to prevent the development of hypertension in CAP-HS rats. Superoxideproduction in the mesenteric resistance arteries was increased in CAP-HS compared with CAP-NS, CON-HS, and CON-NS (Pdid not prevent the increase of mesenteric superoxideproduction in CAP-HS rats. CONCLUSIONS: Regardless of increased vascular MnSOd levels, salt

关键词： superoxides tempol afferent neurons capsaicin denervation dietary sodium chloride nitric oxide

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Ethical challenges in mass drug administration for reducing childhood mortality:a qualitative study

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Infectious diseases of Poverty 2022年第5期11卷 93-94页

作者： Ahmed Alasmar alex C.Kong Anthony d.So Matthew deCamp 不详 division of General Internal Medicine and Center for Bioethics and Humanities Department of MedicineUniversity of Colorado School of MedicineUniversity of Colorado Anschutz Medical Campus13080 E.19th AveMail Stop B137AuroraCO 80045USA

Background:Mass drug administration(MdA)of medications to entire at-risk communities or populations has shown promise in the control and elimination of global infectious *** of the broad-spectrum antibiotic azithromycin has demonstrated the potential to reduce childhood mortality in children at risk of premature death in some global ***,MdA of antibiotics raises complex ethical challenges,including weighing near-term benefts against longer-term risks—particularly the development of antimicrobial resistance that could diminish antibiotic efectiveness for current or future *** aim of this study was to understand how key actors involved in MdA perceive the ethical challenges of ***:We conducted 35 semi-structured interviews from december 2020–February 2022 with investigators,funders,bioethicists,research ethics committee members,industry representatives,and others from both highincome countries(HICs)and low-and middle-income countries(LMICs).Interview participants were identifed via one of seven MdA studies purposively chosen to represent diversity in terms of use of the antibiotic azithromycin;use of a primary mortality endpoint;and whether the study occurred in a high child mortality *** were analyzed using constructivist grounded theory ***:The most frequently discussed ethical challenges related to meaningful community engagement,how to weigh risks and benefts,and the need to target MdA We developed a concept map of how participants considered ethical issues in MdA for child mortality;it emphasizes MdA’s place alongside other public health interventions,empowerment,and *** over an ethical double standard in weighing risks and benefts emerged as a unifying theme,albeit one that participants interpreted in radically diferent *** thought MdA for reducing child mortality was ethically obligatory;others suggested it was ***:Ethical challenges raised by MdA of antib

关键词： Antimicrobial resistance decolonizing global health Mass drug administration Child mortality Ethics Global health equity

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A simple umbelliferone based fluorescent probe for the detection of nitroreductase

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 311-314页

作者： Adam C. Sedgwick alex Hayden Barry Hill Steven d. Bull Robert B. P. Elmes Tony d. James department of Chemistry University of Bath Bath BA2 7AY UK department of Chemistry Maynooth University Maynooth Co. Kildare Ireland

A simple nitrobenzyl-umbelliferone （NCOU1） was synthesised containing a nitroreductase （NTR） trigger moiety. The presence of NTR, resulted in the fragmentation of the parent molecule and release of the highly emissive fluorophore umbelliferone via an NTR-catalyzed reduction of the nitro group. In the presence of the NTR enzyme, NCOU1 gave rise to a 5-fold increase in fluorescence intensity at 455 nm and was selective for NTR over other reductive enzymes. These results indicate that NCOU1 can be used as a simple assay for the detection of NTR.

关键词： NITRO RAdICALS NTSR1 gene FLUORESCENT PROBES Skimmetin Nitroreductases noise-temperature ratio

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Comparative characterization of mesenchymal stem cells from different age groups of cynomolgus monkeys

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Science China(Life Sciences) 2010年第5期53卷 563-572页

作者： ZHANG Y.alex Cell Therapy Center Xuanwu HospitalCapital Medical Universityand Key Laboratory of NeurodegenerationMinistry of Education

Bone marrow mesenchymal stem cells(BM-MSCs) are a potential tool for cell therapy and tissue *** this study,we carried on a comparative study of the characteristics of MSCs from different age cynomolgus monkeys.A variety of factors,including donor age,must be considered before further applications,and various tests should be used to properly assess MSCs before the clinical application,especially when a prolonged culture and ex vivo expansion is necessary.

关键词： cynomolgus monkey mesenchymal stem cells differentiation expansion safety

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Cotton-harvester-flow simulator for testing cotton yield monitors

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International Journal of Agricultural and Biological Engineering 2010年第1期3卷 44-49页

作者： Ruixiu Sui J.alex Thomasson S.d.Filip To USdA-ARS Cotton Ginning Research Unit StonevilleMS 38776USA Biological and Agricultural Engineering department Texas A&M UniversityCollege StationTX 77843USA Agricultural and Biological Engineering department Mississippi State UniversityMississippi StateMS 39762USA

An experimental system was developed to simulate the pneumatic flow arrangement found in picker-type cotton *** simulation system was designed and constructed for testing a prototype cotton yield monitor developed at Mississippi State *** simulation system was constructed to approximate the pneumatic cotton flow system of a cotton picker,and was capable of operating with varying cotton flow *** simulator was tested with different cotton flow rates,and the relationship between feeder rate and amount of conveyed seed cotton was found to be ***,the simulator was used to conduct tests with the novel optical cotton yield monitor,which proved accurate at measuring the amount of seed cotton flowing through the ***,some differences between laboratory testing and field-testing were noted:seed cotton becomes fluffed and twisted when recycled through the simulator,and seed cotton stored in the laboratory tends to be of lower moisture content than cotton during *** differences should be considered when using a laboratory simulator to test cotton yield monitors.

关键词： cotton yieldmonitor precision agriculture sensor cotton harvester

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Changes in fetal mannose and other carbohydrates induced by a maternal insulin infusion in pregnant sheep

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Journal of Animal Science and Biotechnology 2015年第2期6卷 222-229页

作者： Laura d Brown Stephanie R Thorn alex Cheung Jinny R Lavezzi Frederick C Battaglia Paul J Rozance Perinatal Research Center Division of Neonatology Department of Pediatrics University of Colorado Denver School of Medicine Center for Women’s Health Research University of Colorado Denver School of Medicine

Background： The importance of non-glucose carbohydrates, especially mannose and inositol, for normal development is increasingly recognized. Whether pregnancies complicated by abnormal glucose transfer to the fetus also affect the regulation of non-glucose carbohydrates is unknown. In pregnant sheep, maternal insulin infusions were used to reduce glucose supply to the fetus for both short （2-wk） and long （8-wk） durations to test the hypothesis that a maternal insulin infusion would suppress fetal mannose and inositol concentrations. We also used direct fetal insulin infusions （1-wk hyperinsulinemic-isoglycemic clamp） to determine the relative importance of fetal glucose and insulin for regulating non-glucose carbohydrates. Results： A maternal insulin infusion resulted in lower maternal （50%, P 〈 0.01） and fetal （35-45%, P 〈 0.01） mannose concentrations, which were highly correlated （r^2 = 0.69, P 〈 0.01）. A fetal insulin infusion resulted in a 50% reduction of fetal mannose （P 〈 0.05）. Neither maternal nor fetal plasma inositol changed with exogenous insulin infusions. Additionally, maternal insulin infusion resulted in lower fetal sorbitol and fructose （P 〈 0.01）. Conclusions： Chronically decreased glucose supply to the fetus as well as fetal hyperinsulinemia both reduce fetal non-glucose carbohydrates. Given the role of these carbohydrates in protein glycosylation and lipid production, more research on their metabolism in pregnancies complicated by abnormal glucose metabolism is clearly warranted.

关键词： Fructose Glucose Inositol Insulin Mannose Pregnancy

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