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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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气候问题的“根”源

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生物技术世界 2011年第5期8卷 40-47页

作者： richard d.bardgett 周林文

人类已经不可避免地改变了这个世界的生态系统。我们已经耕种了地球表面超过40％的土地，并且把外来物种引入新的地区、向大气层排放二氧化碳、打乱自然的气候循环，还以过量的氮和其他废物污染水体生态系统。

关键词：气候问题水体生态系统地球表面外来物种二氧化碳废物污染大气层耕种

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植物根功能属性的组织方式及进化趋势

植物根功能属性的组织方式及进化趋势

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2018全国植物生物学大会

作者：马泽清郭大立徐兴良卢明镇 richard d.bardgett david M.Eissenstat M.Luke McCormack Lars O.Hedin 中国科学院地理科学与资源研究所 Princeton University The University of Manchester The Pennsylvania State University University of Minnesota

长期以来,植物进化理论主要是基于对叶片、花等地上部分的认识,而对地下根系结构和功能在进化过程中如何组织却鲜为人知。我们经过长期的积累,收集了全球369种植物一级根数据,揭示了全球根系生物地理格局,提出了一个全新的植物进化理论... 详细信息

长期以来,植物进化理论主要是基于对叶片、花等地上部分的认识,而对地下根系结构和功能在进化过程中如何组织却鲜为人知。我们经过长期的积累,收集了全球369种植物一级根数据,揭示了全球根系生物地理格局,提出了一个全新的植物进化理论:在长达4亿年的植物进化过程中,地下吸收根朝更加高效、独立的方向进化,促进了植物的传播。从热带雨林到荒漠,植物吸收根直径整体在变细,倾向于更加灵活的构建方式,对共生真菌依赖性降低,通过该方式,植物单位碳投资的资源获取效率得以优化,从而能够高效地捕获稍纵即逝的水分和养分,增强了植物对环境的适应能力。在水分供应充足的热带雨林,根的设计对水力安全性考虑较低,细根和粗根物种共存,很多系统发育较古老的物种得以保存:而在水分胁迫较强的草原和荒漠,由于季节性资源供应方式不稳定,根系多样性下降。该工作揭示了隐秘在地下的适者生存的规则,在全球尺度证明了根效率是植物进化的动力,对于理解植物资源获取策略、生物地球化学循环和生物多样性保护至关重要。

关键词：吸收根植物进化地下生态学共生真菌植物功能属性

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design of soft magnetic materials

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npj Computational Materials 2022年第1期8卷 17-26页

作者： Ananya Renuka Balakrishna richard d.James Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA90089USA Aerospace and Engineering Mechanics University of MinnesotaMinneapolisMN55455USA

We present a strategy for the design of ferromagnetic materials with exceptionally low magnetic hysteresis,quantified by *** this strategy,we use a micromagnetic algorithm that we have developed in previous research and which has been validated by its success in solving the“Permalloy Problem”—the well-known difficulty of predicting the composition 78.5%Ni of the lowest coercivity in the Fe–Ni system—and by the insight it provides into the“Coercivity Paradox”of ***,the design strategy predicts that cubic materials with large saturation magnetization ms and large magnetocrystalline anisotropy constant κ_(1) will have low coercivity on the order of that of Permalloy,as long as the magnetostriction constantsλ_(100),λ_(111)are tuned to special *** explicit prediction for a cubic material with low coercivity is the dimensionless number(c_(11)−c_(12))λ_(100)^(2)/(2_(κ_(1)))=81 for〈100〉easy *** results would seem to have broad potential application,especially to magnetic materials of interest in energy research.

关键词： magnetic cubic exceptional

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Tissue Engineering to Restore Cardiac Function

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Engineering 2022年第6期8卷 13-17页

作者： richard d.Weisel Toronto General Research Institute Toronto General HospitalUniversity Health Network&Department of SurgeryDivision of Cardiac SurgeryUniversity of TorontoTorontoON M5G 2C4Canada

1. Introduction The purpose of cardiac surgery is to restore the injured heart to full function. For many congenital cardiac defects, appropriate repair is able to establish nearly normal cardiac function. One example of such repair is closing abnormal holes between cardiac chambers in young children, which usually restores normal function that persists for the lifetime of the child. However, the advent of surgery for ischemic heart disease has resulted in new challenges for cardiac surgeons.

关键词： function surgery lifetime

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“Teaching old dogs new tricks”:targeting neural extracellular matrix for normal and pathological aging-related cognitive decline

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Neural Regeneration Research 2019年第4期14卷 578-581页

作者： Adam d.richard Xiao-Hong Lu department of Pharmacology Toxicology and Neuroscience Louisiana State University Health Sciences Center

Cognitive decline is a feature of normal and pathological aging. As the proportion of the global aged population continues to grow, it is imperative to understand the molecular and cellular substrates of cognitive aging for therapeutic discovery. This review focuses on the critical role of neural extracellular matrix in the regulation of neuroplasticity underlying learning and memory in another under-investigated "critical period": the aging process. The fascinating ideas of neural extracellular matrix forming a synaptic cradle in the tetrapartite synapse and possibly serving as a substrate for storage of very long-term memories will be introduced. We emphasize the distinct functional roles of diffusive neural extracellular matrix and perineuronal nets and the advantage of the coexistence of two structures for the adaptation to the ever-changing external and internal environments. Our study of striatal neural extracellular matrix supports the idea that chondroitin sulfate proteoglycan-associated extracellular matrix is restrictive on synaptic neuroplasticity, which plays important functional and pathogenic roles in early postnatal synaptic consolidation and aging-related cognitive decline. Therefore, the chondroitin sulfate proteoglycan-associated neural extracellular matrix can be targeted for normal and pathological aging. Future studies should focus on the cell-type specificity of neural extracellular matrix to identify the endogenous, druggable targets to restore juvenile neuroplasticity and confer a therapeutic benefit to neural circuits affected by aging.

关键词： aging cognitive decline neural extracellular matrix tetrapartite synapse long-term memory storage therapeutic targeting striatum chondroitin sulfate proteoglycan

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Epigenetic regulation of neuronal dendrite and dendritic spine development

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Frontiers in Biology 2010年第4期5卷 304-323页

作者： richard d.SMRT Xinyu ZHAO department of Neuroscience University of New Mexico School of MedicineAlbuquerqueNew Mexico 87131USA

dendrites and the dendritic spines of neurons play key roles in the connectivity of the brain and have been recognized as the locus of long-term synaptic plasticity,which is correlated with learning and *** development of dendrites and spines in the mammalian central nervous system is a complex process that requires specific molecular events over a period of *** has been shown that specific molecules are needed not only at the spine’s point of contact,but also at a distance,providing signals that initiate a cascade of events leading to synapse *** specific molecules that act to signal neuronal differentiation,dendritic morphology,and synaptogenesis are tightly regulated by genetic and epigenetic *** has been shown that the dendritic spine structure and distribution are altered in many diseases,including many forms of mental retardation(MR),and can also be potentiated by neuronal activities and an enriched *** dendritic spine pathologies are found in many types of MR,it has been proposed that an inability to form normal spines leads to the cognitive and motor deficits that are characteristic of *** mechanisms,including dNA methylation,chromatin remodeling,and the noncoding RNA-mediated process,have profound regulatory roles in mammalian gene *** study of epigenetics focuses on cellular effects that result in a heritable pattern of gene expression without changes to genomic *** extensive efforts to understand the molecular regulation of dendrite and spine development,epigenetic mechanisms have only recently been *** this review,we will focus on epigenetic mechanisms that regulate the development and maturation of dendrites and *** will discuss how epigenetic alterations could result in spine abnormalities that lead to MR,such as is seen in fragile X and Rett *** will also discuss both general methodology and recent technological advances in the study of neuronal den

关键词： epigenetics neurodevelopment dendritic spine synapse microRNA methyl-CpG binding protein 2(MeCP2) mental retardation

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Seismic Reflection Characteristics of Naturally-Induced Subsidence Affecting Transportation

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Journal of China University of Geosciences 2009年第3期20卷 496-512页

作者： richard d Miller Jianghai Xia don W Steeples Kansas Geological Survey The University of Kansas Lawrence KS 66047 USA department of Geology The University of Kansas Lawrence KS 66047 USA

High-resolution seismic reflections have been used effectively to investigate sinkholes formed from the dissolution of a bedded salt unit found throughout most of Central Kansas. Surface subsidence can have devastating effects on transportation structures. Roads, rails, bridges, and pipelines can even be dramatically affected by minor ground instability. Areas susceptible to surface subsidence can put public safety at risk. Subsurface expressions significantly larger than surface depressions are consistently observed on seismic images recorded over sinkholes in Kansas. Until subsidence reaches the ground surface, failure appears to be controlled by compressional forces evidenced by faults with reverse orientation. Once a surface depression forms or dissolution of the salt slows or stops, subsidence structures are consistent with a tensional stress environment with prevalent normal faults. detecting areas of rapid subsidence potential, prior to surface failure, is the ultimate goal of any geotechnical survey where the ground surface is susceptible to settling. Seismic reflection images have helped correlate active subsidence to dormant paleofeatures, project horizontal growth of active sinkholes based on subsurface structures, and appraise the risk of catastrophic failure.

关键词： shallow seismic reflection imaging subsidence sinkhole.

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Clinical significance of mesenteric panniculitis-like abnormalities on abdominal computerized tomography in patients with malignant neoplasms

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World Journal of Gastroenterology 2016年第48期22卷 10601-10608页

作者： Eli d Ehrenpreis Grigory Roginsky richard M Gore University of Chicago Center for the Study of Complex Diseases Gastroenterology North Shore University Health System Highland Park Hospital department of Radiology North Shore University HealthS ystem

AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHOdS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical *** In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.

关键词： Panniculitis Peritoneal X ray Neoplasms Computed tomography Small intestine Misty mesentery Lymphoma Tomography Positron emission tomography

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Monte Carlo sampling for error propagation in linear regression and applications in isochron geochronology

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Science Bulletin 2019年第3期64卷 189-197页

作者： Yang Li Shuang Zhang richard Hobbs Camila Caiado Adam d.Sproson david Selby Alan d.Rooney State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences department of Earth Sciences Durham University department of Geology and Geophysics Yale University department of Mathematical Sciences Durham University Atmosphere and Ocean Research Institute The University of Tokyo

Geochronology is essential for understanding Earth's history. The availability of precise and accurate isotopic data is increasing; hence it is crucial to develop transparent and accessible data reduction techniques and tools to transform raw mass spectrometry data into robust chronological data. Here we present a Monte Carlo sampling approach to fully propagate uncertainties from linear regressions for isochron dating. Our new approach makes no prior assumption about the causes of variability in the derived chronological results and propagates uncertainties from both experimental measurements(analytical uncertainties) and underlying assumptions(model uncertainties) into the final age *** synthetic examples, we find that although the estimates of the slope and y-intercept(hence age and initial isotopic ratios) are comparable between the Monte Carlo method and the benchmark‘‘Isoplot" algorithm, uncertainties from the later could be underestimated by up to 60%, which are likely due to an incomplete propagation of model uncertainties. An additional advantage of the new method is its ability to integrate with geological information to yield refined chronological constraints. The new method presented here is specifically designed to fully propagate errors in geochronological applications involves linear regressions such as Rb-Sr, Sm-Nd, Re-Os, Pt-Os, Lu-Hf, U-Pb(with discordant points),Pb-Pb and Ar-Ar.

关键词： Linear regression Isochron Geochronology Uncertainty propagation Monte Carlo Isoplot

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