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trade-off between microbial carbon use efficiency and specific nutrient-acquiring extracellular enzyme activities under reduced oxygen

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Soil Ecology Letters 2023年第2期5卷 43-53页

作者： Ji Chen Irene Cordero Daryl L.Moorhead Jennifer K.Rowntree lorae t.simpson Richard D.Bardgett Hayley Craig Department of Agroecology Aarhus University8830 TjeleDenmark Aarhus University Centre for Circular Bioeconomy Aarhus University8830 TjeleDenmark iCLIMAtE Interdisciplinary Centre for Climate Change Aarhus University4000 RoskildeDenmark Department of Earth and Environmental Sciences The University of ManchesterOxford RoadManchesterM139PTUK Department of Environmental Sciences University of Toledo2801 W.Bancroft St.ToledoOH 43606-3390USA School of Biological and Marine Sciences University of PlymouthDrake CircusPlymouthPL48AAUK Florida Oceanographic Society 890 NE Ocean BlvdStuartFL 34996USA NatureMetrics Occam CourtSurrey Research ParkGuildfordGU27HJUK

Mangroves are one of the most ecologically sensitive ecosystems to global climate change,which have cascading impacts on soil carbon(C),nitrogen(N)and phosphorus(P)***,mangroves are experiencing increasing N and P loadings and reduced oxygen availability due to intensified climate change and human ***,both direct and interactive effects of these perturbations on microbially mediated soil C,N and P cycling are poorly ***,we simultaneously investigated the effects of N and P loadings and reduced oxygen on microbial biomass,microbial respiration,and extracellular enzyme activities(EEAs)in mangrove *** calculated the microbial metabolic quotient(qCO_(2)),which is regarded as a useful inverse metric of microbial C use efficiency(CUE).Our results show that reduced oxygen significantly increases both qCO_(2) and microbial specific EEAs(enzyme activity per unit of microbial biomass)for C-,N-and P-acquisition regardless of N or P ***,we found that qCO_(2) positively correlated with microbial specific EEAs under reduced oxygen,whereas no clear relationship was detected under ambient *** results suggest that reduced oxygen increases microbial specific EEAs at the expense of increasing microbial respiration per unit biomass,indicating higher energy cost per unit enzyme production.

关键词： reduced oxygen extracellular enzyme microbial respiration nutrient acquisition nutrient addition mangrove

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Structural confirmation of sulconazole sulfoxide as the primary degradation product of sulconazole nitrate

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Journal of Pharmaceutical Analysis 2018年第2期8卷 96-102页

作者： Qun Xu Ashraf Khan Di Gao Kristie M.Adams Fatkhulla tadjimukhamedov Shane tan John t.simpson Compendial Development Laboratory United States Pharmacopeia

Sulconazole has been reported to degrade into sulconazole sulfoxide via sulfur oxidation; however,structural characterization data was lacking and the potential formation of an N-oxide or sulfone could not be excluded. to clarify the degradation pathways and incorporate the impurity profile of sulconazole into the United States Pharmacopeia–National Formulary(USP–NF) monographs, a multifaceted approach was utilized to confirm the identity of the degradant. the approach combines stress testing of sulconazole nitrate, chemical synthesis of the degradant via a hydrogen peroxide-mediated oxidation reaction,semi-preparative HPLC purification, and structural elucidation by LC–MS/MS and NMR *** determination was primarily based on the comparison of spectroscopic data of sulconazole and the oxidative degradant. the mass spectrometric data have revealed a Mc Lafferty-type rearrangement as the characteristic fragmentation pathway for alkyl sulfoxides with a β-hydrogen atom, and was used to distinguish the sulfoxide from N-oxide or sulfone derivatives. Moreover, the generated sulconazole sulfoxide was utilized as reference material for compendial procedure development and validation, which provides support for USP monograph modernization.

关键词： Sulconazole nitrate Sulconazole sulfoxide Forced degradation Structural characterization LC–MS/MS

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Identification of isopeptidase activity in the midgut of insects： Purification, properties and nutritional ecology of a Hofmannophila pseudospretella （Lepidoptera： Oecophoridae） larval enzyme

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Insect Science 2010年第4期17卷 325-334页

作者： Robert M. simpson John t. Christeller Plant and Food Research Institute Tennant Drive Palmerston North 4474 Private Bag 11 030 New Zealand

A γ-glutamyl transpeptidase （isopeptidase） has been purified 580-fold to homogeneity from the midgut of keratinophagous larvae of Hofmannophila pseudospretella. the enzyme is a single polypeptide of molecular mass 80 kDa. the enzyme was identified by its hydrolytic activity against the synthetic substrate, γ-glutamyl-AMC, its molecular mass and inhibition profile compared to other γ-glutamyl transpeptidases. the enzyme is low or absent from most other insect digestive systems apart from other keratinophagous lepidopteran larvae and predatory carabids. While isopepfide bonds are present in high levels of the proteins in the diet of keratinophages, their presence in the diet of predatory beetles has not been established.

关键词： γ-glutamyl transpeptidase Hofmannophila pseudospretella isopeptidase,keratinophagous nutritional ecology

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Phylogeny and evolution of Perezia(Asteraceae:Mutisieae:Nassauviinae)

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Journal of Systematics and Evolution 2009年第5期47卷 431-443页

作者： Beryl B.simpson Mary t.K.ARROYO Sandra SIPE Marta DIAS de MORAES Joshua McDILL Integrative Biology and Plant Resources Center The University of Texas1 University Station A6700AustinTX 78712USA Facultad de Ciencias Universidad de ChileCasilla 653Santiago de ChileChile Universidade Federal do Acre Campus FlorestaCruzeiro do SulAcreBrazil

A molecular phylogenetic analysis of most of the species of Perezia reveals that,as traditionally defined,the genus is not monophyletic with two species more closely related to Nassauvia than to *** addition,our results show that Burkartia(Perezia) lanigera is related to Acourtia and is the only member of that clade in South *** remaining species are monophyletic and show a pattern of an early split between a western temperate and an eastern subtropical clade of *** the western clade,the phylogeny indicates a pattern of diversification that proceeded from southern,comparatively low-elevation habitats to southern high-elevation habitats,and ultimately into more northern high-elevation *** most derived clades are found in the high central Andes,where significant radiation has occurred.

关键词： Andes biogeography Mutisieae Nassauviinae Perezia.

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An examination of predictive markers for successful sperm extraction procedures:a linear model and systematic review

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Asian Journal of Andrology 2023年第1期25卷 38-42页

作者： Nicholas Major K Russ Edwards Kit.simpson Marc Rogers Department of Urology Medical University of South CarolinaCharlestonSC 29425USA Department of Healthcare Leadership and Management Medical University of South CarolinaCharlestonSC 29425USA Department of Urology University of North CarolinaChapel HillNC 27514USA

the authors performed a comprehensive review of current literature to create a model comparing commonly evaluated variables in male factor infertility,for example,follicle-stimulating hormone(FSH),testicular volume(tV),and testosterone(t),to better predict sperm retrieval rate(SRR).twenty-nine studies were included,9 with data on conventional testicular sperm extraction(ctESE)for a total of 1227 patients and 20 studies including data on microdissection testicular sperm extraction(mtESE)for a total of 4760 patients.A weighted-means value of SRR,FSH,t,and tV was created,and a weighted linear regression was then used to describe associations among SRR,type of procedure,FSH,t,and *** this study,weighted-means values demonstrated mtESE to be superior to ctESE with an SRR of 51.9%vs 40.1%.Multiple weighted linear regressions were created to describe associations among SRR,procedure type,FSH,t,and *** models showed that for every 1.19 mIU ml^(−1)increase in FSH,there would be a significant decrease in SRR by 1.0%.Seeking to create a more clinically relevant model,FSH values were then divided into normal,moderate elevation,and significant elevation categories(FSH20 mIU ml^(−1),respectively).For an index patient undergoing ctESE,the retrieval rates would be 57.1%,44.3%,and 31.2%for values normal,moderately elevated,and significantly elevated,*** conclusion,in a large meta-analysis,mtESE was shown to be more successful than ctESE for sperm *** has an inverse relationship to SRR in retrieval techniques and can alone be predictive of ctESE SRR.

关键词： follicle-stimulating hormone meta-analysis microtesticular sperm extraction nonobstructive azoospermia testicular sperm retrieval

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A Note on the Relationship Between temperature and Water Vapor over Oceans, Including Sea Surface temperature Effects

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Advances in Atmospheric Sciences 2006年第1期23卷 141-148页

作者： C.-L. SHIE W.-K. tAO J. simpson Goddard Earth Sciences and technology Center University of MarylandBaltimore CountyBaltimoreMaryland 21250USA Laboratory for AtmospheresNASA Goddard Space Flight CenterGreenbeltMaryland 20771USA Laboratory for Atmospheres NASA Goddard Space Flight CenterGreenbeltMaryland 20771USA

An ideal and simple formulation is successfully derived that well represents a quasi-linear relationship found between the domain-averaged water vapor, Q （ram）, and temperature, t （K）, fields for the three tropical oceans （i.e., the Pacific, Atlantic and Indian Oceans） based on eleven GEOS-3 [Goddard Earth Observing System （EOS） Version-3] global re-analysis monthly products. A Q - t distribution analysis is also performed for the tropical and extra-tropical regions based on in-situ sounding data and numerical simulations [GEOS-3 and the Goddard Cumulus Ensemble （GCE） model]. A similar positively correlated Q - t distribution is found over the entire oceanic and tropical regions; however, Q increases faster with t for the former region. It is suspected that the tropical oceans may possess a moister boundary layer than the tropics. the oceanic regime falls within the lower bound of the tropical regime embedded in a global, curvilinear Q - t relationship. A positive correlation is also found between t and sea surface temperature （SSt）; however, for one degree of increase in t, SSt is found to increase 1.1 degrees for a warmer ocean, which is slightly less than an increase of 1.25 degrees for a colder ocean. this seemingly indicates that more （less） heat is needed for an open ocean to maintain an air mass above it with a same degree of temperature rise during a colder （warmer） season [or in a colder （warmer） region]. Q and SSt are also found to be positively correlated. Relative humidity （RH） exhibits similar behaviors for oceanic and tropical regions. RH increases with increasing SSt and t over oceans, while it increases with increasing t in the tropics. RH, however, decreases with increasing temperature in the extratropics. It is suspected that the tropical and oceanic regions may possess a moister local boundary layer than the extratropics so that a faster moisture increase than a saturated moisture increase is favored for the former regions. t, Q, saturated water v

关键词： moisture temperature relationship quasi-equilibrium states tropics oceans

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Nitrate reduction capacity of the oral microbiota is impaired in periodontitis:potential implications for systemic nitric oxide availability

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International Journal of Oral Science 2024年第1期16卷 52-61页

作者： Bob t.Rosier William Johnston Miguel Carda-Diéguez Annabel simpson Elena Cabello-Yeves Krystyna Piela Robert Reilly Alejandro Artacho Chris Easton Mia Burleigh Shauna Culshaw Alex Mira Department of Genomics and Health FISABIO FoundationCenter for Advanced Research in Public HealthValenciaSpain Department of Biological and Biomedical Sciences Glasgow Caledonian UniversityGlasgowUK Oral Sciences University of Glasgow Dental SchoolSchool of MedicineDentistry and NursingCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Sport and Physical Activity Research Institute University of the West of ScotlandBlantyreScotland Instituto de Biomedicina de Valencia Consejo Superior de Investigaciones Científicas(IBV-CSIC)ValenciaSpain CIBER Center for Epidemiology and Public Health MadridSpain

the reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity(NRC)and, therefore, nitric oxide availability has not been evaluated. the current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitratereducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals(P tasets with n = 20–82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. the oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate(a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment(P t recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria(P t effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.

关键词： impaired intake nitrate

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Everything you always wanted to know about metallic hydrogen but were afraid to ask

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Matter and Radiation at Extremes 2020年第3期5卷 25-30页

作者： Eugene Gregoryanz Cheng Ji Philip Dalladay-simpson Bing Li Ross t.Howie Ho-Kwang Mao Centre for Science at Extreme Conditions and School of Physics and Astronomy University of EdinburghEdinburgh EH93FDUnited Kingdom Center for High Pressure Science and technology Advanced Research Shanghai 201203China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China

the hydrogen molecule is made from the first and lightest element in the periodic *** hydrogen gas is either compressed or cooled,it forms the simplest molecular *** solid exhibits many interesting and fundamental physical *** is believed that if the density of the solid is increased by compressing it to very high pressures,hydrogen will transform into the lightest known metal with very unusual and fascinating properties,such as room temperature superconductivity and/or *** this article,we provide a critical look at the numerous claims of hydrogen metallization and the current experimental state of affairs.

关键词： hydrogen metallic solid

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Synthesis and Crystal Structure of Ethyl 2-(6-(1,3-Dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) Butanoate

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Chinese Journal of Structural Chemistry 2009年第5期28卷 585-589页

作者：吴道新罗斐贤莫洪波王晓光任叶果 simpson Jim 黄明智 School of Chemistry and Biological Engineering Changsha University of Science and TechnologyChangsha Hunan 410076 China Key Laboratory of Chemical Biology and traditional Chinese Medicine Research (Ministry of Education of China) Hunan Normal UniversityChangsha 410081 China National Engineering Research Center for Agrochemicals Hunan Research Institute of Chemical IndustryChangsha 410007 China Department of Chemistry University of OtagoPO Box 56 Dunedin New Zealand

the title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. the crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, t= 296（2） K, R = 0.0508 and wR = 0.1478.

关键词： synthesis crystal structure ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b]oxazin-4(3H)-yl) butanoate herbicidal protox inhibitors

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Structural Studies on the Cu–H System under Compression

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Engineering 2019年第3期5卷 505-509页

作者： Jack Binns Miriam Pena-Alvarez Mary-Ellen Donnelly Eugene Gregoryanz Ross t. Howie Philip Dalladay-simpson Center for High Pressure Science and technology Advanced Research (HPStAR) Shanghai 201203 China Centre for Science at Extreme Conditions The University of Edinburgh Edinburgh EH9 3FD UK Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

Hydrogen chemistry at extreme pressures is currently subject to extensive research due to the observed and predicted enhanced physical properties when hydrogen is incorporated in numerous binary systems. Despite the high reactivity of hydrogen, the noble metals (Cu, Ag, and Au) display an outstanding resilience to hydride formation, with no reports of a stable compound with a hydrogen molar ratio - 1 at room temperature. Here, through extreme compression and in situ laser heating of pure copper in a hydrogen atmosphere, we explore the affinity of these elements to adopt binary compounds. We report on the phase behavior and stabilities in the Cu–H system, analyzed via synchrotron X-ray diffraction, up to pressures of 50 GPa. We confirm the existence of the previously reported c0-CuH0.15, c1-CuH0.5, and e-Cu2H phases. Most notably, we report the highest hydrogen-content noble-metal hydride stable at room temperature to date: c2-CuH0.65, which was synthesized through laser heating. this study furthers our understanding of hydrogen-transition metal chemistry and may find applicability in future hydrogen-storage applications.

关键词： High pressure Hydrogen storage Noble metal chemistry

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