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Open Journal of Ecology 2012年第4期2卷 167-177页

作者： Chelsea D. Jones katherine E. Woods William n. Setzer Department of Chemistry University of Alabama in Huntsville Huntsville USA

The overall goal of the project was to test the hypothesis that Lamium amplexicaule and Lamium purpureum, weedy invasive species to north America, use phytotoxic allelochemicals in interplant competition. The chemical compositions of the essential oils from the aerial parts of L. amplexicaule and L. purpureum have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils and several essential oil components have been screened for phytotoxic activity on lettuce (Lactuca sativa) and perennial ryegrass (Lolium perenne) as well as nematocidal activity against Caenorhabditis elegans, brine shrimp (Artemia salina) lethality, and insecticidal activity against the red imported fire ant (Solenopsis invicta × richteri). L. amplexicaule essential oil was composed largely of α-pinene, β- pinene, 1-octen-3-ol, (E)-caryophyllene, and germacrene D, while L. purpureum oil was dominated by α-pinene, β-pinene, 1-octen-3-ol, β-elemene, and germacrene D. neither essential oil exhibited notable phytotoxicity or lethality against nema-todes, brine shrimp, or fire ants. It is unlikely, therefore, that the allelopathy observed in these Lamium species is due to volatile phytochemical constituents.

关键词： Allelopathy Essential Oil Composition Lamium amplexicaule Lamium purpureum

Soil Enzyme Activities and Organic Matter Composition Affected by 26 Years of Continuous Cropping

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Pedosphere 2016年第5期26卷 618-625页

作者： Fugen DOU Alan L.wright Rao S.MYLAVARAPU JIAnG Xianjun John E.MATOCHA Texas A&M AgriLife Research Center at Beaumont BeaumontTX 77713(USA) University of Florida Indian River Research&Education CenterFt.PierceFL 34945(USA) University of Florida Soil&Water Science Dept.GainesvilleFL 32611(USA) Southwest University College of Resources and EnvironmentChongqing(China) Texas A&M University Agricultural Research and Extension CenterCorpus ChristiTX 78406(USA)

The study was to determine the long-term effects of subtropical monoculture and rotational cropping systems and fertilization on soil enzyme activities and soil C, n, and P levels. Cropping systems included continuous sorghum(Sorghum bicolor L.), cotton(Gossypium hirsutum L.), corn(Zea mays L.), and cotton/sorghum rotations after 26 years of treatment imposition. Soil under continuous sorghum and continuous corn had 15% and 11%, respectively, greater C concentrations than soil under continuous *** C was 10% higher at 0–7.5 cm than at 7.5–15 cm. Total n followed similar trends with soil depth as organic C. Continuous sorghum had 19% higher total n than other crop species and rotations. With fertilization, continuous cotton had the highest total P at 0–7.5 cm and sorghum had the highest at 7.5–15 cm. Soil total P was 14% higher at 0–7.5 than at 7.5–15 cm, and fertilization increased 15% total P compared to unfertilized soil. Arylsulfatase, alkaline phosphatase, and β-d-glucosidase activity were the highest for sorghum and the lowest for cotton. Rotation increased enzyme activities compared to continuous cotton but not for continuous sorghum. Of all crop species and rotations, continuous cotton generally showed the lowest levels of organic matter and enzyme activities after 26 years. Fertilization significantly increased the yields for all cropping systems, but rotation had no significant effect on either sorghum or cotton lint yield compared to each crop grown in monoculture. Long-term cropping did not increase soil organic matter levels beyond short-term gains, indicating the difficulty in promoting C sequestration in subtropical soils.

关键词： C sequestration fertilization monoculture rotation subtropical soil

Autotrophic and Heterotrophic nitri?cation in a Highly Acidic Subtropical Pine Forest Soil

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Pedosphere 2016年第6期26卷 904-910页

作者： FAEFLEn J.Sarwee LI Shiwei XIn Xiaoping Alan L.wright JIAnG Xianjun College of Resources and Environment Southwest UniversityChongqing 400715(China) Everglades Research&Education Center University of FloridaBelle Glade FL 33430(USA)

The occurrence of nitri?cation in some acidic forest soils is still a subject of ***?cation of main nitri?cation pathways in acidic forest soils is still largely *** yellow soil(Oxisol) samples were selected to test whether nitri?cation can occur or not in acidic subtropical pine forest *** contributions of autotrophs and heterotrophs to nitri?cation were studied by adding selective nitri?cation inhibitor *** nH^+_4-n concentrations decreased,but nO^-_3-n concentrations increased signi?cantly for the no-nitrapyrin control during the ?rst week of incubation,indicating that nitri?cation did occur in the acidic subtropical *** calculated net nitri?cation rate was 0.49 mg n kg^(-1)d^(-1)for the no-nitrapyrin control during the ?rst week of *** amendment resulted in a signi?cant reduction of nO^-_3-n *** nitri?cation rate averaged0.28 mg n kg^(-1)d^(-1)and the heterotrophic nitri?cation rate was 0.21 mg n kg^(-1)d^(-1)in the ?rst ***-oxidizing bacteria(AOB) abundance increased slightly during incubation,but nitrapyrin amendment signi?cantly decreased AOB amo A gene copy numbers by about 80%.However,the ammonia-oxidizing archaea(AOA) abundance showed signi?cant increases only in the last 2weeks of incubation and it was also decreased by nitrapyrin *** results indicated that nitri?cation did occur in the present acidic subtropical pine forest soil,and autotrophic nitri?cation was the main nitri?cation *** AOA and AOB were the active biotic agents responsible for autotrophic nitri?cation in the acidic subtropical pine forest soil.

关键词： acidic yellow soil ammonia-oxidizing archaea ammonia-oxidizing bacteria net nitrification rate nitrapyrin nitrification inhibitor

Delayed referral for liver transplant evaluation worsens outcomes in chronic liver disease patients requiring inpatient transplant evaluation

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World Journal of Transplantation 2023年第4期13卷 169-182页

作者： katherine M Cooper Alessandro Colletta nicholas J Hathaway Diana Liu Daniella Gonzalez Arslan Talat Curtis Barry Anita Krishnarao Savant Mehta Babak Movahedi Paulo n Martins Deepika Devuni Department of Medicine UMass Chan Medical SchoolWorcesterMA 01605United States Department of Medicine Division of GastroenterologyUMass Chan Medical SchoolWorcesterMA 01605United States Department of Surgery Transplant DivisionUMass Chan Medical SchoolWorcesterMA 01605United States

BACKGROUnD Indications to refer patients with cirrhosis for liver transplant evaluation(LTE)include hepatic decompensation or a model for end stage liver disease(MELDna)score≥*** studies have evaluated how delaying referral beyond these criteria affects patient *** To evaluate clinical characteristics of patients undergoing inpatient LTE and to assess the effects of delayed LTE on patient outcomes(death,transplantation).METHODS This is a single center retrospective cohort study assessing all patients undergoing inpatient LTE(n=159)at a large quaternary care and liver transplant center between 10/23/2017-7/31/*** referral was defined as having prior indication(decompensation,MELD-na≥15)for LTE without *** referral was defined as referrals made within 3 mo of having an indication based on practice *** regression and Cox Hazard Regression were used to evaluate the relationship between delayed referral and patient *** Many patients who require expedited inpatient LTE had delayed *** regarding transplant candidacy were a leading cause of delayed ***,delayed referrals negatively affected overall patient outcome and an independent predictor of both death and not receiving a *** referral was associated with a 2.5 hazard risk of *** Beyond initial access to an liver transplant(LT)center,delaying LTE increases risk of death and reduces risk of LT in patients with chronic liver *** is substantial opportunity to increase the percentage of patients undergoing LTE when first clinically *** is crucial for providers to remain informed about the latest guidelines on liver transplant candidacy and the transplant referral process.

关键词： Liver transplantation Liver transplant evaluation Liver transplant referral Patient access Equity Patient outcomes

Fungal infection dynamics in response to temperature in the lepidopteran insect Galleria mellonella

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Insect Science 2018年第3期25卷 454-466页

作者： Vadim Y. Kryukov Olga n. Yaroslavtseva Miranda M. A. Whitten Maksim V. Tyurin katherine J. Ficken Carolyn Greig nadja R. Melo Viktor V. Glupov Ivan M. Dubovskiy Tariq M. Butt Institute of Systematics and Ecology of Animals Siberian Branch of Russian Academy of Science Novosibirsk Russia Institute of Life Science College of Medicine Swansea University Swansea Wales UK Department of Biosciences College of Science Swansea University Swansea Wales UK

This study examines how the dynamics of fungus-insect interactions can be modulated by temperature. The wax moth, Galleria mellonella, is a well-studied and important model insect whose larvae in the wild develop optimally at around 34 ℃ in beehives. However, surprisingly little research on wax moths has been conducted at relevant temperatures. In this study, the entomopathogenic fungus Metarhizium robertsii inflicted rapid and substantial mortality on wax moth larvae maintained at a constant temperature of 24 ℃, but at 34 ℃ a 10 fold higher dose was required to achieve an equivalent mortality. The cooler temperature favored fungal pathogenicity, with condial adhesion to the cuticle, germination and hemocoel invasion all significantly enhanced at 24 ℃, compared with 34 ℃. The wax moth larvae immune responses altered with the temperature, and with the infective dose of the fungus. Enzyme-based immune defenses （lysozyme and phenoloxidase） exhibited enhanced activity at the warmer temperature. A dramatic upregulation in the basal expression of galiomicin and gallerimycin was triggered by cooling, and this was augmented in the presence of the fungus. Profiling of the predominant insect epicuticular fatty acids revealed a 4-7 fold increase in palmetic, oleic and linoleic acids in larvae maintained at 24 ℃ compared with those at 34 ℃, but these failed to exert fungistatic effects on topically applied fungus. This study demonstrates the importance of choosing environmental conditions relevant to the habitat of the insect host when determining the dynamics and outcome of insect/fungus interactions, and has particular significance for the application of entomopathogens as biocontrol agents.

关键词： biocontrol entomopathogenic fungus immunity Metarhizium temperature

Burn injury prevention in low-and middleincome countries:scoping systematic review

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Burns & Trauma 2021年第1期9卷 123-144页

作者： Kate Price Kwang Chear Lee katherine E.Woolley Henry Falk Michael Peck Richard Lilford naiem Moiemen College of Medical and Dental Sciences University of BirminghamEdgbastonBirminghamB152TTUK University Hospital Birmingham nHS Foundation Trust Queen Elizabeth Hospital BirminghamMindelsohn WayEdgbastonBirminghamB152WBUK Institute of Applied Health Research University of BirminghamEdgbastonBirminghamB152TTUK Adjunct Professor of Environmental Health Emory UniversityRollins School of Public HealthAtlantaGA 30322US Clinical Professor of Surgery University of Arizona College of MedicinePhoenixAZ 85004US

Background:Burn injuries are a leading cause of morbidity and disability,with the burden of disease being disproportionately higher in low-and middle-income countries(LMIC).Burn prevention programmes have led to significant reductions in the incidence of burns in high-income ***,a previous systematic review published in 2015 highlighted that implementation and evaluation of similar programmes has been limited in *** objective of this scoping review and narrative synthesis was to summarise and understand the initiatives that have been carried out to reduce burn injuries in LMIC and their ***:We aimed to identify publications that described studies of effectiveness of burn prevention interventions applied to any population within a LMIC and measured burn incidence or burns-related *** publications were identified from three ***,data was extracted from manuscripts identified in the systematic review published by Rybarczyk et *** then performed a search for manuscripts on burn prevention interventions published between January 2015 and September ***,we extracted data from two systematic reviews where burn evidence was not the primary outcome,which were identified by senior authors.A quality assessment and narrative synthesis of included manuscripts were ***:In total,24 manuscripts were identified and categorized according to intervention *** majority of manuscripts(n=16)described education-based *** manuscripts focused on environmental modification interventions and four adopted a mixedmethods *** of the education-based initiatives demonstrated improvements in knowledge relating to burn safety or first aid,however few measured the impact of their intervention on burn *** manuscripts described population-based educational interventions and noted reductions in burn *** one of the four manuscripts describing environmental modification i

关键词： Burns Prevention Low-and-middle income countries Systematic review

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即将看到:冷原子模拟超导体

物理 2019年第9期48卷 601-601页

作者：戴闻 katherine wright 中国科学院理化技术研究所

自从1986年发现铜基超导体以来,这种材料一直困扰着物理学家。致力于将超冷原子安放在有序激光晶格的物理学家认为,他们的实验很快就能对上述困扰提供所需的线索。这些实验可能接近产生一个高温超导体的模型,其中的原子扮演电子的角色。

关键词：高温超导体原子模拟物理学家超冷原子光晶格实验电子

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压力下的超导体

物理 2015年第6期44卷 384-384页

作者：戴闻 katherine wright 中国科学院理化技术研究所不详

最近的一份报告称：实验已经表明,H2S在加压条件下超导转变温度高达190 K。如果得到证实,这一发现将冲击铜氧化合物保持的超导转变温度最高记录（164 K）,并朝室温超导体的发现迈出新的一步。超高临界温度被认为与非常规超导电性相关,... 详细信息

最近的一份报告称：实验已经表明,H2S在加压条件下超导转变温度高达190 K。如果得到证实,这一发现将冲击铜氧化合物保持的超导转变温度最高记录（164 K）,并朝室温超导体的发现迈出新的一步。超高临界温度被认为与非常规超导电性相关,其物理机制至今仍是未知的。但是,西班牙Donostia国际物理中心的Ion Errea和他的同事们,已经证明了上述假设对于高压下的H2S是不正确的。

关键词：超导体超导转变温度压力物理机制铜氧化合物高临界温度加压条件超导电性

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生物量子何时展现自我

物理 2015年第4期44卷 259-259页

作者：戴闻 katherine wright 中国科学院理化技术研究所

对于许多生物学过程而言（其中包括：视觉，光合作用，动物的磁信号导航等），光子（即光量子）的吸收起着重要的作用。举个例子，某些鸟类，在它们的视网膜上有激发产生的光电子，这些光电产的运动受地球磁场的操控。而鸟类为了长途飞... 详细信息

对于许多生物学过程而言（其中包括：视觉，光合作用，动物的磁信号导航等），光子（即光量子）的吸收起着重要的作用。举个例子，某些鸟类，在它们的视网膜上有激发产生的光电子，这些光电产的运动受地球磁场的操控。而鸟类为了长途飞行之路线识别，

关键词：生物学过程光量子光合作用地球磁场光电子磁信号视网膜鸟类

Oral mucosal lipids are antibacterial against Porphyromonas gingivalis, induce ultrastructural damage, and alter bacterial lipid and protein compositions

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International Journal of Oral Science 2013年第3期5卷 130-140页

作者： Carol L Fischer katherine S Walters David R Drake Deborah V Dawson Derek R Blanchette Kim A Brogden Philip W Wertz Dows Institute for Dental Research College of Dentistry The University of Iowa Central Microscopy Research Facility College of Dentistry The University of Iowa Department of Endodontics College of Dentistry The University of Iowa Department of Pediatric Dentistry College of Dentistry The University of Iowa Department of Periodontics College of Dentistry The University of Iowa Department of Oral Pathology Radiology & Medicine College of Dentistry The University of Iowa

Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria;however,little is known about their spectrum of antimicrobial activity or mechanisms of action against oral *** this study,we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis,an important colonizer of the oral cavity implicated in *** inhibitory concentrations,minimal bactericidal concentrations,and kill kinetics revealed variable,but potent,activity of oral mucosal and salivary lipids against ***,indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria,although specific components of bacterial membranes are also likely *** micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma *** information,coupled with the association of treatment lipids with *** lipids revealed via thin layer chromatography,suggests that the plasma membrane is a likely target of lipid antibacterial *** a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and n-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique *** stress response,including proteins important in fatty acid biosynthesis,metabolism and energy production,protein processing,cell adhesion and *** or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.

关键词： antimicrobial lipid fatty acid Porphyromonasgingivalis sphingoid base sphingolipid ultrastructure