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Strategies towards statistically robust interpretations of in situ U-Pb zircon geochronology

Geoscience Frontiers 2016年第4期7卷 581-589页

作者： christopher j.Spencer christopher L.Kirkland Richard j.M.Taylor The Institute of Geoscience Research(TIGeR) Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Centre for Exploration Targeting-Curtin Node Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Australian Research Council Centre of Excellence for Core to Crust Fluid SystemsPerthWA 6102Australia

Zircon U-Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon （via laser ablation and secondary ionization mass spectrometry） has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable （e.g. detrital zircons as a sedi- ment fingerprinting method）. The ease of acquisition, while bringing benefit to the Earth science com- munity, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U -Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. We discuss a range of data filtering approaches and their inherent limitations （e.g. discordance and the reduced chi-squared; MSWD）. We evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206pb and 207pb/206pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U-Pb datasets will become increasingly pertinent.

关键词： Zircon Geochronology U-Pb Geostatistics MSWD

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Colonoscopic polypectomy and associated techniques

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World journal of Gastroenterology 2010年第29期16卷 3630-3637页

作者： christopher j Fyock Peter V Draganov Division of Gastroenterology Hepatology and NutritionUniversity of Florida

Polypectomy of colonic polyps has been shown to reduce the risk of colon cancer development and is considered a fundamental skill for all endoscopists who perform colonoscopy.A variety of polypectomy techniques and devices are available,and their use can vary greatly based on local availability and *** general,cold forceps and cold snare have been the polypectomy methods of choice for smaller polyps,and hot snare has been the method of choice for larger *** use of hot forceps has mostly fallen out of *** for difficult to remove polyps may require the use of special devices and advanced techniques and has continued to *** a result,the vast majority of polyps today can be removed *** electrocautery is frequently used for polypectomy,endoscopists should be thoroughly familiar with the basic principles of electrosurgery as it pertains to *** of a polypectomy site is an important adjunct to polypectomy and can greatly facilitate future surgery or endoscopic *** two most common post-polypectomy complications are bleeding and *** incidence can be decreased with the use of meticulous polypectomy techniques and the application of some prophylactic *** review will examine the technique of polypectomy and its complications from the perspective of the practicing gastroenterologist.

关键词： Colonic polyp Polypectomy Colonoscopy Polypectomy technique Complications

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Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond

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journal of Environmental Sciences 2023年第2期124卷 522-543页

作者： Mark W.Lusty christopher j.Gobler School of Marine and Atmospheric Sciences Stony Brook UniversitySouthamptonNY 11968USA

This study explored the effects of H_(2)O_(2)on Cyanobacteria and non-target microbes using fluorometry,microscopy,flow cytometry,and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY,*** addition of H_(2)O_(2)(8 mg/L)significantly reduced Cyanobacteria concentrations during a majority of experiments(66%;6 of 9)and significantly increased eukaryotic green and unicellular brown algae in 78%and 45%of experiments,*** heterotrophic bacteria declined significantly following H_(2)O_(2)addition in all experiments,bacteria indicative of potential fecal contamination(Escherichia coli,Enterococcus,fecal coliform bacteria)consistently and significantly increased in response to H_(2)O_(2),evidencing a form of‘pollution swapping’.H_(2)O_(2)more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem *** whole-pond H_(2)O_(2)applications over a twoyear period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or *** bacterial phyla of Cyanobacteria,Actinobacteria,and Planctomycetes were the most negatively impacted by H_(2)O_(2).Microcystis was always reduced by H_(2)O_(2),as was the toxin microcystin,but Microcystis remained dominant even after repeated H_(2)O_(2)*** H_(2)O_(2)favored the growth of eukaryotic algae over potentially harmful Cyanobacteria,the inability of H_(2)O_(2)to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination.

关键词： Indicator bacteria Toxic cyanobacteria Microcystin Microcystis Hydrogen peroxide Bacteria Enterococcus E.coli Pollution swapping

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Enhanced recovery programme in colorectal surgery:Does one size fit all?

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World journal of Gastroenterology 2012年第40期18卷 5661-5663页

作者： Alison Lyon christopher j Payne Graham j MacKay Specialty Registrar in General Surgery West of Scotland RotationGlasgow G4 0SFUnited Kingdom Lister Department of Surgery Glasgow Royal InfirmaryGlasgow G4 0SFUnited Kingdom

Enhanced recovery after surgery(ERAS) employs a multimodal perioperative care pathway with the aim of attenuating the stress response to surgery and accelerating *** has been difficult to determine the relative importance of some of the individual components of these pathways such as epidural analgesia and laparoscopic colorectal *** argue that only a rigid adherence to the published ERAS protocol can achieve the proposed benefits of fast-track *** this article,we explore some of the areas where the evidence base may be changing and ask whether a more flexible and individualised approach should be considered.

关键词： Enhanced recovery Fast-track Laparoscopic Intravenous fluid Postoperative analgesia

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Genome and clonal hematopoiesis stability contrasts with immune,cfDNA,mitochondrial,and telomere length changes during short duration spaceflight

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Precision Clinical Medicine 2024年第1期7卷 1-13页

作者： j.Sebastian Garcia-Medina Karolina Sienkiewicz S.Anand Narayanan Eliah G.Overbey Kirill Grigorev Krista A.Ryon Marissa Burke jacqueline Proszynski Braden Tierney Caleb M.Schmidt Nuria Mencia-Trinchant Remi Klotz Veronica Ortiz jonathan Foox christopher Chin Deena Najjar Irina Matei Irenaeus Chan Carlos Cruchaga Ashley Kleinman jangKeun Kim Alexander Lucaci Conor Loy Omary Mzava Iwijn De Vlaminck Anvita Singaraju Lynn E.Taylor julian C.Schmidt Michael A.Schmidt Kelly Blease juan Moreno Andrew Boddicker junhua Zhao Bryan Lajoie Andrew Altomare Semyon Kruglyak Shawn Levy Min Yu Duane C.Hassane Susan M.Bailey Kelly Bolton jaime Mateus christopher E.Mason Department of Physiology and Biophysics Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine Weill Cornell MedicineNew YorkNY 10021USA Department of Immunology Weill Cornell MedicineCornell UniversityNew YorkNY 10021USA Department of Stem Cell Biology and Regenerative Medicine Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90033USA Space Exploration Technologies Corporation HawthomeCA 90250USA Sovaris Aerospace BoulderCO 80302USA Advanced Pattern Analysis&Human Performance Group BoulderCO 80302USA Children's Cancer and Blood Foundation Laboratories Departments of Pediatrics and Cell and Developmental BiologyDrukier Institute for Children's HealthMeyer Cancer CenterWeill Cornell MedicineNew YorkNY 10021USA Meyer Cancer Center Weill Cornell MedicineNew YorkNY 10065USA Department of Nutrition and Integrative Physiology Florida State UniversityTallahasseeFL 32306USA Department of Systems Engineering Colorado State UniversityFort CollinsCO 80523USA Element Biosciences San DiegoCA 10055USA Department of Environmental and Radiological Health Sciences Colorado State UniversityFort CollinsCO 80523USA Cell and Molecular Biology Program Colorado State UniversityFort CollinsCO 80523USA BioAstra Inc New YorkNYUSA Washington University St Louis Oncology Division St.LouisMO 63100USA Meinig School of Biomedical Engineering Cornell UniversityIthacaNY 14853USA The Feil Family Brain and Mind Research Institute Weill Cornell MedicineNY 10021USA WorldQuant Initiative for Quantitative Prediction Weill Cornell MedicineNew YorkNY 10021USA

Background The Inspiration4(I4)mission,the first all-civilian orbital flight mission,investigated the physiological effects of short-duration spaceflight through a multi-omic *** advances,there remains much to learn about human adaptation to spaceflight's unique challenges,including microgravity,immune system perturbations,and radiation *** To provide a detailed genetics analysis of the mission,we collected dried blood spots pre-,during,and post-flight for DNA *** length was measured by quantitative PCR,while whole genome and cfDNA sequencing provided insight into genomic stability and immune adaptations.A robust bioinformatic pipeline was used for data analysis,including variant calling to assess mutational *** Telomere elongation occurred during spaceflight and shortened after return to ***-free DNA analysis revealed increased immune cell signatures *** significant clonal hematopoiesis of indeterminate potential(CHIP)or whole-genome instability was *** long-term gene expression changes across immune cells suggested cellular adaptations to the space environment persisting months *** Our findings provide valuable insights into the physiological consequences of short-duration spaceflight,with telomere dynamics and immune cell gene expression adapting to spaceflight and persisting after return to *** sequencing data will serve as a reference point for studying the early development of CHIP in astronauts,an understudied phenomenon as previous studies have focused on career *** study will serve as a reference point for future commercial and non-commercial spaceflight,low Earth orbit(LEO)missions,and deep-space exploration.

关键词： genomes clonal hematopoiesis stability immune mitochondria ribosomes spaceflight

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A systematic review of the attractant-decoy and repellent- plant hypotheses: do plants with heterospecific neighbours escape herbivory?

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journal of Plant Ecology 2015年第4期8卷 337-346页

作者： Ally Ruttan christopher j.Lortie Department of Biology York University4700 Keele StreetTorontoOntario M3J1P3Canada

Aims this systematic review highlights the relative support and implica-tions of the attractant-decoy and repellent-plant hypotheses,discuss-ing important linkages between these theories and the opportunity for novel integration into ecological and applied *** an extensive systematic review of the current literature on the attract-ant-decoy and repellent-plant hypotheses was done to describe the following attributes of the research to date:(i)the geographic extent(country and biome)of studies on this topic,(ii)the scope of experi-mental designs used,(iii)the level of support for these hypotheses with respect to the breadth of ecological niches tested,(iv)the level of support for these hypotheses with respect to the classes of herbi-vores examined and,lastly,(v)the ecological impact or purpose of these ***,we summarize important research gaps in the empirical literature on this topic and identify novel opportunities for critical linkages between ecological and applied *** Findingsa total of 37%of experiments testing these two associated hypotheses were done in North america,frequently in either temperate broadleaf(26%of studies)or taiga ecosystems(15%of studies).the majority of these studies involved experimental manipulations such as removing and transplanting vegetation and either tracked or excluded mammalian *** implications were primarily examined(59%of studies),but there were also implications described for agriculture and commercial forestry in 22%of *** repellent-plant hypothesis was well supported in many ecological systems,particularly for mammalian herbivores,but the attractant-decoy hypothesis has been less frequently tested,thereby representing an important research *** herbivores were under-represented in all categories except in applied contexts such as commercial forestry and *** is a clear need for studies to connect these two ecological hypotheses with the manageme

关键词： associated plant defence attractant-decoy herbivory neighbour repellent-plant systematic review

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Exploiting a chink in the armor:engineering broadly neutralizing monoclonal antibodies for SARS-like viruses

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Signal Transduction and Targeted Therapy 2021年第7期6卷 1944-1945页

作者： Mirko Cortese christopher j.Neufeldt Department of Infectious Diseases Molecular VirologyHeidelberg UniversityHeidelbergGermany

In a recent article published in Science,Rappazzo and co-authors1 engineered a human monoclonal antibody to bind and neutralize a broad range of SARS-like *** authors used a directed evolution approach with yeast surface display on antibodies isolated from a SARS-CoV-1 survivor,to engineer a broad-spectrum neutralizing antibody with improved neutralization breath,potency,and resistance to viral spike glycoprotein(S protein)mutations(Fig.1).

关键词： neutral SARS antibodies

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Chromatoprobe as a sample-sparing technique for residual solvent analysis of drug discovery candidates by gas chromatography

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药物分析学报：英文版 2017年第4期7卷 265-269页

作者： christopher j.Poronsky jingfang Qian Cutrone Bristol-Myers Squibb Research and DevelopmentWallingfordCT 06492USA

In drug discovery research, residual solvent measurement is an integral part of purity analysis for synthesis of a drug candidate before it is used for toxicity testing. This is usually carried out using gas chromatography(GC)with direct injection sample introduction. This method requires testing compounds to be soluble at high concentrations( > 50 mg/mL, usually in DMSO) to achieve acceptable sensitivity, a hurdle which is not always achievable for some samples such as cyclic peptides and oligonucleotides. To overcome the limitation associated with the direct injection approach, a new method using the Chromatoprobe thermal extraction device was developed for quantifying residual solvents of drug discovery compounds. This method not only consumes significantly less material(less than 1 mg), but also shows higher sensitivity than the direct injection *** addition, because no diluent is required with the Chromatoprobe thermal extraction, all residual solvents can be detected and measured without further method optimization. In our study, we compared data from GC residual solvent analysis using the Chromatoprobe solid sample introduction to those of the direct injection method for seven in-house samples. Our results showed a good agreement between the data from these two sample introduction methods. Thus, the Chromatoprobe sample introduction method provided a samplesparing alternative to the direct injection method for the measurement of residual solvents in drug *** method can be particularly useful for residual solvent analysis in samples that are available only in limited amounts, poorly soluble, and/or unstable in the diluents used for the direct injection method.

关键词： Chromatoprobe Thermal extraction Gas chromatography Residual solvent Drug discovery

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Neurological and neuropsychological consequences of electrical and lightning shock： review and theories of causation

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Neural Regeneration Research 2017年第5期12卷 677-686页

作者： christopher j.Andrews Andrew D.Reisner Faculty of Medicine-The University of Queensland HerstonAustraliaLightning and Electrical InjuriesMt Ommaney Family PracticeMt OmmaneyBrisbaneAustralia Forensic Diagnostic Center of District Nine CambridgeOHUSA

Injuries from lightning and electrical injuries involve multiple systems of the body, however neurological symptoms are very widely reported. A disabling neuropsychological syndrome is also noted. This paper presents a comprehensive review of neurological and neuropsychological symptoms. Partial theories of causation for these injuries have been advanced, however, there is no convincing explanation for both delay in onset of symptoms and also the genesis of the neuropsychological syndrome. A theory of causation is proposed which satisfies both these constraints. This theory suggests circulating hormones such as cortisol, together with nitric oxide and oxidant free radicals from glutamatergic hyper-stimulation, act on tissues remote from the injury path including the hippocampus. This theory opens a research path to explore treatment options.

关键词： electrical injury lightning injury neurology neuropsychology neuropsychiatry injury trauma

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The floristic relationship between the upland and lowland Carboniferous wetlands of Variscan Euramerica——Evidence from some medullosalean pteridosperm fronds

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journal of Palaeogeography 2019年第2期8卷 130-141页

作者： christopher j.Cleal Borja Cascales-Mi?ana Department of Natural Sciences National Museum Wales CNRS University of Lille

Alethopteris grandinii represents remains of fronds of a medullosalean pteridosperm(probably a small tree) that rapidly migrated across the lowland wetland habitats of Variscan Euramerica in middle Asturian(late Moscovian)*** was probably caused by changing drainage patterns within the lowland coal swamps,in response to climate and landscape ***,these medullosaleans had first appeared rather earlier,in early Bolsovian(early Moscovian) times,in upland wetland *** upland habitats may have pre-adapted these plants to the changed condition in the lowland coal swamps.

关键词： Carboniferous Coal swamps Medullosales Upland Migration

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