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Ammonia-oxidizing archaea and bacteria are structured by geography in biological soil crusts across North American arid lands

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Ecological Processes 2013年第1期2卷 98-107页

作者： Yevgeniy Marusenko scott T Bates Ian Anderson Shannon l Johnson Tanya Soule Ferran Garcia-Pichel School of life Sciences Arizona State UniversityP.O.Box 874501TempeAZ 85287-4501USA Cooperative Institute for Researchin Environmental Sciences University of ColoradoBoulderCO80309USA Bioscience Division B-11Los Alamos National LaboratoryLos AlamosNM87545USA Department of Biology Indiana University-Purdue UniversityFort WayneINUSA

Introduction:Biological soil crusts(BSCs)can dominate surface cover in dry lands worldwide,playing an integral role in arid land biogeochemistry,particularly in N fertilization through fixation and *** is a characteristic and universal N transformation in BSCs that becomes important for the export of N beyond the microscopic bounds of the crust *** contribution of ammonia-oxidizing bacteria(AOB)in BSCs has been shown,but the role and extent of the recently discovered ammonia-oxidizing archaea(AOA)have ***:We sampled various types of crusts in four desert regions across the western United States and characterized the composition and size of ammonia-oxidizing communities using clone libraries and quantitative PCR targeting the amoA gene,which codes for the ammonia monooxygenase enzyme,universally present in ammonia-oxidizing ***:All archaeal amoA sequences retrieved from BSCs belonged to the Thaumarchaeota(Nitrososphaera associated Group I.1b).Sequences from the Sonoran Desert,Colorado Plateau,and Great Basin were indistinguishable from each other but distinct from those of the Chihuahuan *** on amoA gene abundances,archaeal and bacterial ammonia oxidizers were ubiquitous in our survey,but the ratios of archaeal to bacterial ammonia oxidizers shifted from bacterially dominated in northern,cooler deserts to archaeally dominated in southern,warmer ***:Archaea are shown to be potentially important biogeochemical agents of biological soil crust N *** associated with different types of BSCs and biogeographical factors reveal a niche differentiation between AOA and AOB,possibly driven by temperature.

关键词： Biological soil crust Desert Arid amoA Ammonia oxidation Nitrification Nitrogen cycle Thaumarchaeota

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Continuous live cell imaging of cellulose attachment by microbes under anaerobic and thermophilic conditions using confocal microscopy

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Journal of Environmental Sciences 2013年第5期25卷 849-856页

作者： Zhi-Wu Wang Seung-Hwan lee James G.Elkins Yongchao li scott Hamilton-Brehm Jennifer l.Morrell-Falvey BioEnergy Science Center Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN 37831USA College of Food Agricultural and Environmental SciencesThe Ohio State University1328 Dover RdWoosterOH 44691USA National Institute of Advanced Industrial Science and Technology Biomass Refinery Research CenterHiroshimaJapan Department of Forest Biomaterials Engineering College of Forest and Environmental SciencesKangwon National UniversityChuncheon 200-701Korea

live cell imaging methods provide important insights into the dynamics of cellular processes that cannot be derived easily from population-averaged *** the bioenergy field,much research is focused on fermentation of cellulosic biomass by thermophilic microbes to produce biofuels;however,little effort is dedicated to the development of imaging tools to monitor this dynamic biological *** is,in part,due to the experimental challenges of imaging cells under both anaerobic and thermophilic *** an imaging system is described that integrates confocal microscopy,a flow cell device,and a lipophilic dye to visualize *** to technical obstacles regarding suitable fluorescent markers,photodamage during imaging,and maintenance of environmental conditions during imaging are *** system was utilized to observe cellulose colonization by Clostridium thermocellum under anaerobic conditions at 60℃.This method enables live cell imaging of bacterial growth under anaerobic and thermophilic conditions and should be widely applicable to visualizing different cell types or processes in real time.

关键词： thermophile lipophilic dye cellulose biofuel confocal laser scanning microscopy biofilm

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The use of near infrared transmittance kernel sorting technology to salvage high quality grain from grain downgraded due to Fusarium damage

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Animal Nutrition 2015年第1期1卷 41-46页

作者： Michael E.Kautzman Mark l.Wickstrom Tom A.scott Toxicology Centre University of Saskatchewan Department of Veterinary Biomedical Sciences College of Veterinary MedicineUniversity of Saskatchewan Department of Animal and Poultry Science College of AgricultureUniversity of Saskatchewan

The mycotoxins associated with specific Fusarium fungal infections of grains are a threat to global food and feed security. These fungal infestations are referred to as Fusarium Head Blight(FHB) and lead to Fusarium Damaged Kernels(FDK). Incidence of FDK >0.25% will lower the grade, with a tolerance of 5%FDK for export feed grain. During infestation, the fungi can produce a variety of mycotoxins, the most common being deoxynivalenol(DON). Fusarium Damaged Kernels have been associated with reduced crude protein(CP), lowering nutritional, functional and grade value. New technology has been developed using Near Infrared Transmittance(NIT) spectra that estimate CP of individual kernels of wheat, barley and durum. Our objective is to evaluate the technology's capability to reduce FDK and DON of downgraded wheat and ability to salvage high quality safe kernels. In five FDK downgraded sources of wheat,the lowest 20% CP kernels had significantly increased FDK and DON with the high CP fractions having decreased FDK and DON, thousand kernel weights(TKW) and bushel weight(Bu). Strong positive correlations were observed between FDK and DON(r = 0.90); FDK and grade(r = 0.62) and DON and grade(r = 0.62). Negative correlations were observed between FDK and DON with CP(r =-0.27 and-0.32);TKW(r =-0.45 and-0.54) and Bu(r =-0.79 and-0.74). Results show improved quality and value of Fusarium downgraded grain using this technology.

关键词： Fusarium Deoxynivalenol Near infrared Crude protein Mycotoxin

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Does selective logging change ground-dwelling beetle assemblages in a subtropical broad-leafed forest of China？

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Insect Science 2017年第2期24卷 303-313页

作者： Xiao-Dong Yu Chong-ling liu liang lu scott l. Bearer Tian-Hong luo Hong-Zhang Zhou Key laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China The Nature Conservancy Community Arts Center 220 West Fourth Street Williamsport PA USA

Selective logging with natural regeneration is advocated as a near-to-nature strategy and has been implemented in many forested systems during the last decades. However, the efficiency of such practices for the maintenance of forest species are poorly understood. We compared the species richness, abundance and composition of ground- dwelling beetles between selectively logged and unlogged forests to evaluate the possible effects of selective logging in a subtropical broad-leafed forest in southeastern China. Us- ing pitfall traps, beetles were sampled in two naturally regenerating stands after clearcuts （ca. 50 years old, stem-exclusion stage： selectively logged 20 years ago） and two mature stands （〉 80 years old, understory re-initiation stage： selectively logged 50 years ago） during 2009 and 2010. Overall, selective logging had no significant effects on total beetle richness and abundance, but saproxylie species group and some abundant forest species significantly decreased in abundance in selectively logged plots compared with unlogged plots in mature stands. Beetle assemblages showed significant differences between selec- tively logged and unlogged plots in mature stands. Some environmental characteristics associated with selective logging （e.g., logging strategy, stand age, and cover of shrub and moss layers） were the most important variables explaining beetle assemblage structure. Our results conclude that selective logging has no significant impacts on overall richness and abundance of ground-dwelling beetles. However, the negative effects of selective logging on saproxylic species group and some unlogged forest specialists highlight the need for large intact forested areas for sustaining the existence of forest specialist beetles.

关键词： habitat affinity management microhabitat species diversity successionalstage

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lower extremity amputation:the emerging role of targeted muscle reinnervation(TMR)and regenerative peripheral nerve interface(RPNI)

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Plastic and Aesthetic Research 2022年第1期9卷 334-350页

作者： Yoshiko Toyoda Said Azoury Andrew Bauder l.scott levin Stephen Kovach Division of Plastic and Reconstructive Surgery University of PennsylvaniaPhiladelphiaPA 19104USA Department of Plastic and Reconstructive Surgery Memorial Sloan Kettering Cancer CenterNew YorkNY 10065USA Department of Orthopedic Surgery University of PennsylvaniaPhiladelphiaPA 19104USA

lower extremity amputation is increasingly prevalent in the United States,with growing numbers of patients suffering from diabetes and peripheral vascular *** has significant functional sequelae as more than half of patients are unable to ambulate at one year *** mobility and decreasing chronic post-amputation pain can significantly improve the quality of life for these patients and reduce the cost burden on the healthcare *** and reconstructive surgery has been at the forefront of“reconstructive amputation”,in which nerve pedicles can be surgically guided to decrease painful neuroma formation as well as provide targets for myoelectric prosthesis *** herein review post-amputation outcomes,epidemiology of chronic,post-amputation pain,and current treatments,including total muscle reinnervation and regenerative peripheral nerve interface,which are at the forefront of multidisciplinary treatment of lower extremity amputees.

关键词： lower extremity amputation post-amputation pain neuroma targeted muscle reinnervation regenerative peripheral nerve interface

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limb preservation with suprafascial and thin perforator flaps: salvaging osteomyelitis, Charcot collapse and critical limb ischemia

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Plastic and Aesthetic Research 2019年第8期6卷 13-23页

作者： Shawn Diamond Andres F.Doval Benjamin scott Matthew l.Iorio Division of Plastic and Reconstructive Surgery Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215USA Division of Plastic and Reconstructive Surgery University of Colorado Anschutz Medical CenterAuroraCO 80045USA.

AIM: There are limited reports in the United States demonstrating outcomes of primarily thinned fasciocutaneous flaps in the setting of critical limb ischemia, Charcot collapse and osteomyelitis. We hope to determine patient and flap related outcomes in advanced lower extremity disease. Methods: The authors conducted a retrospective review of fasciocutaneous free flaps of variable thickness for lower extremity salvage. Osteomyelitis and non-osteomyelitis patients were compared according to our primary outcome measures: functional ambulation, bone healing and complications to flap and patient. Subgroups with critical limb ischemia, Charcot collapse and diabetic foot were analyzed separately. Results: Fifty-nine patients underwent free flap reconstruction: osteomyelitis (n = 20, 34%), Charcot collapse (n = 22, 37%), and/or critical limb ischemia (n = 12, 20%). All patients underwent anterolateral thigh flaps tailored for defect-specific thicknesses: 17 superthin, 25 suprafascial, 17 subfascial. There were no significant differences between groups in terms of partial and complete flap loss (P = 1.000 and P = 0.108). Ninety-one percent of patients were ambulatory at follow up. Eighty-tive percent of individuals with osteomyelitis cleared their infection demonstrating radiographic bone healing. Two patients developed recalcitrant deep space infections ultimately requiring amputation. Subgroup analysis did not show any differences in flap related complications within the diabetic Charcot population. In multivariate regression, preoperative revascularization was independently associated with failure of limb salvage. ;Conclusion: Primarily thinned perforator flaps performed well in the setting of lower extremity limb salvage, critical limbischemia, osteomyelitis, and the Charcot foot - expanding their role in the armamentarium for lower extremity care.

关键词： Perforator flap diabetic foot limb salvage

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Echocardiography in centenarians： characteristics, utility and follow-up

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Journal of Geriatric Cardiology 2018年第5期15卷 328-333页

作者： Jorge A Brenes-Salazar Jaime de la Fuente Punnaiah Marella Hari Chaliki Christopher scott Heidi M Connolly Roger l Click Department of Cardiovascular Diseases Mayo Clinic Rochester USA Department of Internal Medicine Mayo Clinic Rochester USA Department of Cardiovascular Diseases Mayo Clinic Arizona USA Division of Biostatistics Mayo Clinic Rochester USA

Background Echocardiography has been shown to be a valuable resource in the diagnosis of many cardiac conditions, and can be used in all age groups, from the fetus to the oldest old. In the context of an increasingly aging population, the impact and utility of echocar- diography in centenarians is largely unknown. This study is to determine whether echocardiography in centenarians aids in making clinical patient management decisions. Methods A retrospective review of echocardiograms from 1986 to 2014, at two affiliated tertiary centers, in individuals who were 100 years or older at the time of the examination. Patient and echocardiogram characteristics, management decisions based on echocardiography, and mortality were documented. Results 114 centenarians had echocardiograms, with ages ranging from 100 to 107 years （101 - 1.4 years）. In 82 of the centenarians evaluated （72%）, no changes in management occurred as a consequence of the echocardiogram. From all management changes directly related to the echocardiogram, 81% （n = 26） of these corresponded to medication adjustments; interventional or surgical procedures followed the echocardiogram only in 4% （n = 5） of the total number of centenarians. Echocardiogram-based changes in management were only significant in patients that were referred for congestive heart failure （P = 0.02）. After the echocardiogram was performed, 1-month and 1-year mortality were 15% and 47%, respectively. The median survival after the echocardiogram was obtained was 13 months （range 0.03 to 145 months）, with no difference if there was a change or no change in manage- ment （P = 0.21）. Conclusions Among centenarians undergoing echocardiography, despite additional diagnostic information, echocardio- grams in centenarians influence management in a minority of cases, most commonly in the form of medication changes for treatment of heart failure. A significant proportion of centenarians are deceased within a year of undergoing echocardiographic ass

关键词： Centenarian Echocardiography Geriatric

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Segment boundaries of the adult rat epididymis limit interstitial signaling by potential paracrine factors and segments lose differential gene expression after efferent duct ligation

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Asian Journal of Andrology 2007年第4期9卷 565-573页

作者： Terry T. Tumer Daniel S. Johnston scott A. Jelinsky Jose l. Tomsig Joshua N. Finger Department of Urology University of Virginia Health Science System Charlottesville VA 22908 US Cell Biology University of Virginia Health Science System Charlottesville VA 22908 US Contraception Women＇s Health and Musculoskeletal Biology Wyeth Research Collegeville PA 19426 USA Biological Technologies Molecular Profiling and Biomarker Discovery Wyeth Research Cambridge MA 02140 USA

The epididymis is divided into caput, corpus and cauda regions, organized into intraregional segments separated by connective tissue septa （CTS）. In the adult rat and mouse these segments are highly differentiated. Regulation of these segments is by endocrine, lumicrine and paracrine factors, the relative importance of which remains under investigation. Here, the ability of the CTS to limit signaling in the interstitial compartment is reviewed as is the effect of 15 days of unilateral efferent duct ligation （EDl） on ipsilateral segmental transcriptional profiles. Inter-segmental microperifusions of epidermal growth factor （EGF）, vascular endothelial growth factor （VEGFA） and fibroblast growth factor 2 （FGF2） increased phosphorylation of mitogen activated protein kinase （MAPK） in segments 1 and 2 of the rat epididymis and the effects of all factors were limited by the CTS separating the segments. Microan＇ay analysis of segmental gene expression determined the effect of 15 days of unilateral EDl on the transcriptome-wide gene expression of rat segments 1-4. Over 11 000 genes were expressed in each of the four segments and over 2 000 transcripts in segment 1 responded to deprivation of testicular lumicrine factors. Segments 1 and 2 of control tissues were the most transcriptionally different and EDl had its greatest effects there. In the absence of lumicrine factors, all four segments regressed to a transcriptionally undifferentiated state, consistent with the less differentiated histology. Deprivation of lumicrine factors could stimulate an individual gene＇s expression in some segments yet suppress it in others. Such results reveal a higher complexity of the regulation of rat epididymal segments than that is generally appreciated. （Asian J Androl 2007 July; 9： 565-573）

关键词： efferent duct ligation dedifferentiation proximal epididymis

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Geographic segregation and evidence of density-dependent changes in sex ratios in an abundant colonial waterbird

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Integrative Zoology 2014年第5期9卷 570-582页

作者： Brian S.DORR Katie C.HANSON-DORR Travis l.DeVAUlT Alban GUIllAUMET scott C.BARRAS United States Department of Agriculture Wildlife Services(USDA-WS)National Wildlife Research CenterMississippi Field StationMississippi StateMississippiUSA USDA-WS National Wildlife Research CenterOhio Field StationSanduskyOhioUSA Department of Wildlife Fisheries and AquacultureMississippi State UniversityMississippi StateMississippiUSA USDA-WS MoseleyVirginiaUSA University of Hawaii Office of Research/PIPESHiloHIUSA.

Demographic information,such as geographic segregation of sexes and sex ratio data,is needed to develop,model and evaluate conservation and management strategies for wildlife.A variety of physiological,behavioral and environmental factors can influence segregation of sexes and sex ratios,many of which originate with density-dependent *** from 50:50 sex ratios of double-crested cormorants(Phalacrocorax auritus)collected during control efforts in breeding and wintering areas across their eastern range of the USA were evaluated using using a Z-test as well as Stouffer’s weighted *** addition,a specifically-designed randomization test was used to evaluate density-dependent effects on primary sex ratios in cormorants from egg collections and colony nest count data over a 21-year *** collected from breeding colonies were strongly male-biased,whereas cormorants collected from feeding flocks were slightly biased toward *** were partly segregated by sex on the wintering grounds,with significantly more males found in areas with intensive channel catfish *** null hypothesis that females produced a balanced sex ratio independent of number of nesting cormorants was rejected:more male embryos were produced during rapid population growth,whereas at maximum nesting number more female embryos were *** populations stabilized,the sex ratio was more *** examination of sex ratios indicates that different management methods and locations result in sex-biased culling of ***-biased culling in cormorants could make population reduction efforts more efficient and reduce overall *** suggest further research to examine density-dependent effects on primary sex ratios documented here.

关键词： Ashmole’s halo management Phalacrocorax auritus population growth sex ratio theory

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Scalable, Green Chain Transfer Agent for Cationic RAFT Polymerizations

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Chinese Journal of Chemistry 2023年第4期41卷 399-404页

作者： scott W.Spring Chloe S.Cerione Jesse H.Hsu Shelby l.Shankel Brett P.Fors Department of Chemistry and Chemical Biology Cornell UniversityIthacaNew York14853 United States

Cationic polymerizations of vinyl ethers have gained recent attention due to their ability to produce robust,biorenewable *** developments have been largely enabled by the advent of cationic reversible addition−fragmentation chain-transfer(RAFT)polymerization;however,the scalability and sustainability of this method are hindered by current chain-transfer agents(CTAs),which exist as viscous,colored oils requiring complex syntheses and solvent-intensive ***,we produce a solid,colorless CTA through a green synthetic route in 83%yield on a 50-gram *** investigate the utility of this CTA in chemical,electrochemical,photochemical,and acid-initiated methods,revealing that it achieves efficient polymerization with excellent control over molecular weight,low dispersity values,high chain end fidelity,and temporal control in cationic RAFT polymerizations.

关键词： Vinyl ethers CTA Cationic polymerization Green RAFT

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