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National Science Review 2022年第12期9卷 21-23页

作者： christopher h.martin Department of Integrative Biology University of California Museum of Vertebrate Zoology University of California

Although numerous theoretical models of the feasibility and necessary conditions for sympatric speciation abound in the literature,clear-cut examples in nature remain elusive.And,as always in speciation research,this statement strongly depends on your definition of sympatric speciation [1-3].If using the biogeographic definition of sympatric speciation as divergence between individuals in a population within’cruising range’of each other [4],

关键词： CLEAREST EXAMPLES GENE FLOW

Institutional analysis of intra-and post-operative tracheostomy management for risk reduction

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World Journal of Otorhinolaryngology-head and Neck Surgery 2022年第4期8卷 370-377页

作者： Laura E.henry Ellen A.Paul Joshua h.Atkins Niels D.martin Ara A.Chalian christopher h.Rassekh Department of Otorhinolaryngology-head and Neck Surgery University of PennsylvaniaPhiladelphia19104PAUSA Department of Anesthesiology and Critical Care University of PennsylvaniaPhiladelphia19104PAUSA Department of Traumatology Surgical Critical Careand Emergency SurgeryUniversity of PennsylvaniaPhiladelphia19104PAUSA

Objectives:Determine variability in intra-and post-operative management of tracheostomies(trachs)at our institution as existing literature suggests that trachs are a frequent trigger for airway-related emergencies.Catalyze the development of an institution-wide protocols for trach care.Methods:A 39-question online survey was sent to 55 providers who perform open and percutaneous trachs at three of the hospitals within our large,urban,academic medical center.These providers were identified by surveillance of the operating room schedules for 1 year.Results:The survey was completed by 40 of the 53 eligible providers(75.5%).Response rate by question varied.Respondents included members of all departments that perform trachs at our institution(Otorhinolaryngology,Trauma Surgery,Thoracic Surgery,General Surgery,Cardiovascular Surgery and Interventional Pulmonology).While most responses demonstrated uniformity in practice,notable variations included the following:80%of percutaneous trach providers stated that morbid obesity was not a contraindication to performing a trach outside of the operating room(n=20)while 58%of open trach providers stated that morbid obesity was a contraindication;only 35%of open trach providers perform a Bjork flap(n=350).The survey also identified significant variability in practice with regards to timing of trach suture removal.Discussion:Lack of uniformity was identified in several practices related to intra-and post-operative tracheostomy care.Results did,however,trend toward consensus in many areas.The results are being used to establish a more consistent approach to tracheostomy management across our institution to ensure standardization of practice amidst the rapidly evolving practices of trach placement.Implications for practice:With ongoing evolution in the methods of trach placement and its management,the concepts put forth here will be a resource for health care providers at other institutions to consider intra-institutional analysis and establishment of practice standardization.

关键词： Open tracheostomy Percutaneous tracheostomy Quality improvement Risk reduction Standardization

Fusarium pseudograminearum and F.culmorum affect the root system architecture of bread wheat

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作物学报：英文版 2023年第1期11卷 316-321页

作者： Ahmed Saad Jack christopher Anke martin Stephen McDonald Cassandra Percy Centre for Crop health University of Southern QueenslandToowoombaQLD 4350Australia University of Queensland Queensland Alliance for Agriculture and Food Innovation(QAAFI)Leslie Research FacilityToowoombaQLD 4350Australia

Yield losses of bread wheat due to crown rot can be more severe when drought conditions occur during the grain-filling period.Root architecture characteristics are important for soil exploration and belowground resource acquisition and are essential for adaptation to water-limited environments.Traits such as root angle,length and density have been strongly associated with acquisition efficiency and contribute to yield stability of the crop.The impact of crown rot pathogens on wheat root architecture is poorly understood.We examined differences in root angle,length and number,as well as dry root weight of the crown rot-susceptible bread wheat cultivar,Livingston inoculated with one of two crown rot pathogens Fusarium culmorum or Fusarium pseudograminearum in a transparent-sided root observation chamber.Significant adverse impacts on plant health and growth were revealed by visual discolouration of the leaf sheaths;fresh and dry shoot weight;leaf area of the oldest and the youngest fully expanded leaf and leaf number.Values of most recorded root system measurements were reduced when inoculated with either F.culmorum or F.pseudograminearum.In contrast,root angle was increased in the presence of F.culmorum but was not significantly changed by F.pseudograminearum.The development of whiteheads and grain losses in bread wheat caused by crown rot have previously been associated with blockages of the vascular systems.The method employed here was able to identify differences in the pathogen impacts on roots,which were not detected using previous systems.This research indicates that in the presence of F.culmorum and F.pseudograminearum infection,not only reductions in the size and biomass of the shoot system but also changes in the length,biomass and architecture of the root system could play an important role in yield loss.

关键词： Crown rot Root characteristics Livingston Wheat

A novel aptamer-based small RNA delivery platform and its application to cancer therapy

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Genes & Diseases 2023年第3期10卷 1075-1089页

作者： Toshihiko Tanno Peng Zhang christopher Bailey Yin Wang Wannaporn Ittiprasert martin Devenport Pan Zheng Yang Liu OncoC4 Inc.RockvilleMD 20850USA Division of Immunotherapy Institute of Human VirologyUniversity of Maryland School of MedicineBaltimoreMD 21201USA Department of Microbiology Immunology and Tropical MedicineSchool of Medicine and HygieneGeorge Washington UniversityNW WashingtonDC 20037USA

Major challenges such as nuclease degradation, rapid renal clearance, non-specific delivery, poor cellular uptake and inflammatory response have limited the clinical application of small RNA-mediated gene silencing. To overcome these challenges, we designed a novel targeting small RNA delivery platform comprising of three oligonucleotides: (1) a guide RNA sequence, (2) part of a passenger sequence linked to a DNA aptamer via a PEG linker, and (3) another passenger sequence conjugated to cholesterol, which assemble through complementary base pair annealing. Remarkably, in the presence of magnesium, this molecule self-assembled into a nanoparticle with a hydrophobic cholesterol core, hydrophilic RNA oligonucleotide shell and PEG-linked DNA aptamer flare. The nanoparticles conferred protection to the RNA oligonucleotides against nuclease degradation, which increased bioavailability, and reduced systemic inflammatory responses. The aptamer allowed targeted delivery of RNA therapeutics through cell-specific surface markers, and once inside the cell, the nanoparticles induced lysosomal leakage that released the RNA oligonucleotides into the cytosol to achieve gene silencing. We created a c-Kit-targeting miR-26a delivery particle that specifically accumulated in c-Kit^(+) breast cancer, significantly increased T cell recruitment, and inhibited tumor growth. Regression of large established tumors were achieved when the nanoparticle was used in combination with anti-CTLA-4 monoclonal antibody.

关键词： Aptamer Cancer Micellar nanoparticle miRNA Tar get delivery

The application of Fourier transform mid-infrared(FTIR) spectroscopy to identify variation in cell wall composition of Setaria italica ecotypes

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Journal of Integrative Agriculture 2017年第6期16卷 1256-1267页

作者： christopher Brown Antony P.martin christopher P.L.Grof Centre for Plant Science School of Environmental and Life Sciences University of Newcastle Newcastle 2308 Australia Light Sheet Microscopy Unit Hunter Medical Research Institute Newcastle 2305 Australia

Cell wall composition in monocotyledonous grasses has been identified as a key area of research for developing better feedstocks for forage and biofuel production.Setaria viridis and its close domesticated relative Setaria italica have been chosen as suitable monocotyledonous models for plants possessing the C4 pathway of photosynthesis including sorghum,maize,sugarcane,switchgrass and Miscanthus×giganteus.Accurate partial least squares regression（PLSR）models to predict S.italica stem composition have been generated,based upon Fourier transform mid-infrared（FTIR）spectra and calibrated with wet chemistry determinations of ground S.italica stem material measured using a modified version of the US National Renewable Energy Laboratory（NREL）acid hydrolysis protocol.The models facilitated a high-throughput screening analysis for glucan,xylan,Klason lignin and acid soluble lignin（ASL）in a collection of 183 natural S.italica variants and clustered them into classes,some possessing unique chemotypes.The predictive models provide a highly efficient screening tool for large scale breeding programs aimed at identifying lines or mutants possessing unique cell wall chemotypes.Genes encoding key catalytic enzymes of the lignin biosynthesis pathway exhibit a high level of conservation with matching expression profiles,measured by RT-q PCR,among accessions of S.italica,which closely mirror profiles observed in the different developmental regions of an elongating internode of S.viridis by RNASeq.

关键词： monocotyledonous C4 grasses lignin biosynthesis Fourier transform mid-infrared spectroscopy Setaria italica

Analysis of new bone,cartilage,and fibrosis tissue in healing murine allografts using whole slide imaging and a new automated histomorphometric algorithm

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Bone Research 2015年第4期3卷 226-234页

作者： Longze Zhang martin Chang christopher A Beck Edward M Schwarz Brendan F Boyce Center for Musculoskeletal Research School of Medicine and DentistryUniversity of Rochester Medical Center

histomorphometric analysis of histologic sections of normal and diseased bone samples,such as healing allografts and fractures,is widely used in bone research.however,the utility of traditional semi-automated methods is limited because they are labor-intensive and can have high interobserver variability depending upon the parameters being assessed,and primary data cannot be re-analyzed automatically.Automated histomorphometry has long been recognized as a solution for these issues,and recently has become more feasible with the development of digital whole slide imaging and computerized image analysis systems that can interact with digital slides.here,we describe the development and validation of an automated application（algorithm）using Visiopharm＇s image analysis system to quantify newly formed bone,cartilage,and fibrous tissue in healing murine femoral allografts in high-quality digital images of h＆E/alcian blue-stained decalcified histologic sections.To validate this algorithm,we compared the results obtained independently using OsteoMeasureTM and Visiopharm image analysis systems.The intraclass correlation coefficient between Visiopharm and OsteoMeasure was very close to one for all tissue elements tested,indicating nearly perfect reproducibility across methods.This new algorithm represents an accurate and labor-efficient method to quantify bone,cartilage,and fibrous tissue in healing mouse allografts.

关键词： cartilage slide automated healing fibrous Figure automatically sections segmentation quantify

Assessing volcanic origins within detrital zircon populations——A case study from the Mesozoic non-volcanic margin of southern Australia

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Geoscience Frontiers 2019年第4期10卷 1371-1381页

作者： Milo Barham christopher L. Kirkland martin Danisík Centre for Exploration Targeting (CET)- Curtin Node The Institute for Geoscience Research (TIGeR)School of Earth and Planetary SciencesCurtin UniversityGPO Box U1987PerthWA 6845Australia Geohistory Facility John de Laeter CenterCurtin UniversityGPO Box U1987PerthWA 6845Australia

Detrital zircon U/Pb geochronology is a common tool used to resolve stratigraphic questions,inform basin evolution and constrain regional geological histories.In favourable circumstances,detrital zircon populations can contain a concomitant volcanic contribution that provides constraints on the age of deposition.however,for non-volcanic settings,proving isolated detrital zircon grains are from contemporaneous and potentially remote volcanism is challenging.here we use same grain(U-Th)/he thermochronology coupled with U/Pb geochronology to identify detrital zircon grains of contemporary volcanic origin.(U-Th)/he ages from Cretaceous zircon grains in southern Australia define a single population with a weighted mean age of 104±6.1 Ma.indistinguishable from zircon U/Pb geochronology and palynology(~104.0-107.5 Ma).Detrital zircon trace-element geochemistry is consistent with a continental signature for parent rocks and coupled with detrital grain ages,supports derivation from a>2000 km distant early-to mid-Cretaceous Whitsunday Volcanic Province in eastern Australia.Thus,integration of biostratigraphy,single-grain zircon double-dating(geochronology and thermochronology)and grain geochemistry enhances fingerprinting of zircon source region and transport history.A distal volcanic source and rapid continental-scale transport to southern Australia is supported here.

关键词： Provenance Grain history Thermochronology Geochronology Source to sink Trace-elements

Combustion mechanism development and CFD simulation for the prediction of soot emission during flaring

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Frontiers of Chemical Science and Engineering 2016年第4期10卷 459-471页

作者： Anan Wang helen h. Lou Daniel Chen Anfeng Yu Wenyi Dang Xianchang Li christopher martin Vijaya Damodara Ajit Patki Dan F. Smith Department of Chemical Engineering Lamar University Beaumont TX 77710 USA SINOPEC Safety Engineering Institute Qingdao 266000 China Department of Mechanical Engineering Lamar University Beaumont TX 77710 USA Department of Chemistry Lamar University Beaumont TX 77710 USA

Industrial Flares are important safety devices to bum off the unwanted gas during process startup, shutdown, or upset. however, flaring, especially the associated smoke, is a symbol of emissions from refineries, oil gas fields, and chemical processing plants. how to simultaneously achieve high combustion efficiency （CE） and low soot emission is an important issue. Soot emissions are influenced by many factors. Flare operators tend to over-steam or over-air to suppress smoke, which results in low CE. how to achieve optimal flare performance remains a question to the industry and the regulatory agencies. In this paper, regulations in the US regarding flaring were reviewed. In order to determine the optimal operating window for the flare, different combus- tion mechanisms related to soot emissions were summar- ized. A new combustion mechanism （Vsoot） for predicting soot emissions was developed and validated against experimental data. Computational fluid dynamic （CFD） models combined with Vsoot combustion mechanism were developed to simulate the flaring events. It was observed that simulation results agree well with experimental data.

关键词： flare soot emission combustion mechanism,CFD simulation

Intraocular lens power calculation following laser refractive surgery

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Eye and Vision 2015年第1期2卷 63-70页

作者： christopher hodge Colm McAlinden Michael Lawless Colin Chan Gerard Sutton Aifric martin Vision Eye Institute Level 3270 Avenue ChatwoodVictoriaNSWAustralia Save Sight Institute University of SydneySydneyNSWAustralia Flinders University Bedford ParkAdelaideSouth AustraliaAustralia Wenzhou Medical College WenzhouZhejiangChina School of Optometry and Vision Science University of New South WalesSydneyAustralia University College Dublin MontroseDublinIreland

Refractive outcomes following cataract surgery in patients that have previously undergone laser refractive surgery have traditionally been underwhelming.This is related to several key issues including the preoperative assessment(keratometry)and intraocular lens power calculations.Peer-reviewed literature is overwhelmed by the influx of methodology to manipulate the corneal or intraocular lens(IOL)powers following refractive surgery.This would suggest that the optimal derivative formula has yet been introduced.This review discusses the problems facing surgeons approaching IOL calculations in these post-refractive laser patients,the existing formulae and programs to address these concerns.Prior published outcomes will be reviewed.

关键词： Cataract Laser refractive surgery Intraocular lens calculations

Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes

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Journal of Mountain Science 2019年第2期16卷 243-255页

作者： Derek J.martin christopher ELY Beverley C.WEMPLE Department of Geography and Planning Appalachian State University Department of Geography University of Vermont

The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km^2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.

关键词： Bank erosion Páramo Fluvial geomorphology Andes