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Ectomycorrhizal and Saprotrophic Fungal Communities Vary Across mm-Scale Soil Microsites Differing in Phosphatase Activity

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Pedosphere 2019年第3期29卷 344-359页

作者： Aaron GODIN Denise BROOKS Sue j. GRAYSTON Melanie D. j.NES Biology Department University of British Columbia Okanagan campus Kelowna V1V 1V7 (Canada) Department of Forest & Conservation Sciences Faculty of Forestry University of British Columbia Vancouver V6T 1Z4 (Canada)

To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imprinting to guide mm-scale sampling from microsites with high and low phosphatase activities in birch/douglas-fir stands. Study 1 involved sampling one root window per site at 12 sites of different ages(stands);study 2 was conducted at one of the stem-exclusion stands, at which 5 root windows had been installed. Total fungal and ectomycorrhizal(EM) fungal terminal-restriction fragment length polymorphism(TRFLP)fingerprints differed between high-and low-phosphatase activity microsites at 8 of 12 root windows across 12 sites. Where differences were detected, fewer EM fungi were detected in high-than low-phosphatase activity microsites. Using 5 root windows at one site,next-generation sequencing detected similar fungal communities across microsites, but the ratio of saprotrophic to EM fungal reads was higher in high-phosphatase activity microsites in the two windows that had low EM fungal richness. In windows with differences in fungal communities, both studies indicated that EM fungi were less successful than saprotrophic fungi in colonizing fine-scale,organic matter-rich microsites. Fine-scale sampling linked with in situ detection of enzyme activity revealed relationships between soil fungal communities and phosphatase activity that could not be observed at the scales employed by conventional approaches, thereby contributing to the understanding of fine-scale phosphorus cycling in forest soils.

关键词： ectomycorrhizae fine scale fungal communities phosphatase root windows saprotrophic fungi soil imprinting

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Risk factors, surgical complications and graft survival in liver transplant recipients with early allograft dysfunction

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 423-429页

作者： douglas Bastos-Neves Paolo Rogerio de Oliveira Salvalaggio Marcio Dias de Almeida Digestive and Hepatobiliary Surgery Hospital Sao Vicente de PauloRio de JaneiroBrazil Liver Transplant Unit Hospital Israelita Albert EinsteinSao PauloBrazil

Background: Early allograft dysfunction (EAD) is a severe complication after liver transplantation. The associated risk factors and complications have re-gained recent interest. This study investigated risk factors, survival and complications associated with EAD in a large liver transplant center in Latin America. Methods: Retrospective, unicenter, cohort, based on data from adult patients undergoing first deceaseddonor liver transplant from j.nuary 2009 to December 2013. EAD was defined by one or more of the following:(i) bilirubin ≥10 mg/dL on postoperative day 7;(ii) international normalized ratio ≥1.6 on postoperative day 7, and (iii) alanine aminotransferase or aspartate aminotransferase > 2000 IU/L within the first seven days after transplant. Results: A total of 602 patients were included;of these 34.2% developed EAD. Donor risk factors were male ( P = 0.007), age between 50 and 59 years ( P = 0.034), overweight ( P = 0.028) or grade I obesity ( P = 0.012), sodium > 157 mmol/L ( P = 0.002) and grade IV ischemia/reperfusion inj.ry ( P = 0.002). Cold ischemia time ≥10 h ( P = 0.008) and warm ischemia time ≥40 min ( P = 0.013) were the surgical factors. Male ( P 157 mmol/L and grade Ⅳ ischemia/reperfusion inj.ry. Cold ischemia time ≥10 h and warm ischemia time ≥40 min were the surgical risk factors. Male was the only recipient protective factor. Patients with EAD had higher reoperations and graft loss rates.

关键词： Graft survival Liver transplantation Primary graft dysfunction Donor evaluation

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Regeneration Responses in Partially-Harvested Riparian Management Zones in Northern Minnesota

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j.urnal of Water Resource and Protection 2014年第6期6卷 556-564页

作者： douglas N. Kastendick Brian j. Palik Eric K. Zenner Randy K. Kolka Charles R. Blinn j.shua j. Kragthorpe Penn State University University Park USA University of Minnesota St. Paul USA USDA Forest Service Northern Research Station Grand Rapids USA

Trees serve important functions in riparian areas. Guidelines often suggest how riparian forests should be managed to sustain functions, including tree retention and increasing the component of conifers and later-successional species. While regeneration of early successional species is not discouraged, there is uncertainty about the ability to regenerate the latter along with more desirable species. We investigated the regeneration of species differing in successional status and growth forms under different amounts of residual basal area. The study was conducted in riparian sites in northern Minnesota USA. At each site, one portion of the riparian area was uncut, while a downstream area was harvested to 16 or 8 m2·ha-1. Woody vegetation was sampled before and five-years after harvesting and summarized as early, mid-, and late successional hardwoods, as well as conifers and shrubs. After five years, the density of early successional trees was lower at 16 m2·ha-1 compared to 8 m2·ha-1;densities in both treatments were lower than in clearcuts. Densities of mid- and late successional hardwoods and conifers did not increase in either treatment. The higher basal area treatment resulted in a lower density of shrubs, which might be important for establishing more desirable tree species, although this may require additional activities to promote establishment.

关键词： Riparian Management Overstory Retention Regeneration RMZ Riparian Forest

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Synthetic biology identifies the minimal gene set required for paclitaxel biosynthesis in a plant chassis

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Molecular Plant 2023年第12期16卷 1951-1961页

作者： Youj.n Zhang lorenz Wiese Hao Fang Saleh Alseekh Leonardo Perez de Souza Federico Scossa j.hn Molloy Mathias Christmann Alisdair R.Fernie Max-Planck-Institut fur Molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany Center of Plant Systems Biology and Biotechnology 4000 PlovdivBulgaria Institute of Chemistry and Biochemistry Freie Universitat BerlinTakustraBe 314195 BerlinGermany Department of Biomolecular Systems Max Planck Institute of Colloids and Interfaces14476 PotsdamGermany Research Center for Genomics and Bioinformatics(CREA-GB) Via Ardeatina 54600178 RomeItaly

The diterpenoid paclitaxel(Taxol)is a chemotherapy medication widely used as a first-line treatment against several types of solid *** supply of paclitaxel from natural sources is ***,missing knowledge about the genes involved in several specific metabolic steps of paclitaxel biosynthesis has rendered it difficult to engineer the full *** this study,we used a combination of transcriptomics,cell biology,metabolomics,and pathway reconstitution to identify the complete gene set required for the heterologous production of *** identified the missing steps from the current model of paclitaxel biosynthesis and confirmed the activity of most of the missing enzymes via heterologous expression in Nicotiana ***,we identified a new C4β-C20 epoxidase that could overcome the first bottleneck of metabolic *** used both previously characterized and newly identified oxomutases/epoxidases,taxane 1β-hydroxylase,taxane 9aα-hydroxylase,taxane 9α-dioxygenase,and phenylalanine-CoA ligase,to successfully biosynthesize the key intermediate baccatin Ill and to convert baccatin Ill into paclitaxel in *** combination,these approaches establisha metabolic route to taxoidbiosynthesis and provide insights into the unique chemistry that plants use to generate complex bioactive metabolites.

关键词： paclitaxel biosynthesis synthetic biology baccatin Ill biosynthesis Taxus

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Earth meets spirit

Earth meets spirit

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作者： photography douglas Beasley

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由粉末冶金Fe(Cr,Mo)钢制备的同步器齿毂的力学性能

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粉末冶金技术 2013年第4期31卷 309-313页

作者： lorenz S Sigl Patrice Delarbre Sinterstahl GmbH Ftissen D-87629德国

试验测定零件本身的强度性能是困难的,因此通常不采用此类数据。本文介绍了一种用于直接测定零件本身强度性能的方法,即用水射流切割零件,随后进行磨加工制备小型矩形试棒(约40mm×5mm×5mm)测定数据。采用典型粉末冶金零件——粉末冶... 详细信息

试验测定零件本身的强度性能是困难的,因此通常不采用此类数据。本文介绍了一种用于直接测定零件本身强度性能的方法,即用水射流切割零件,随后进行磨加工制备小型矩形试棒(约40mm×5mm×5mm)测定数据。采用典型粉末冶金零件——粉末冶金高合金化Fe(Cr,Mo)钢同步器齿毂制备的小型试棒测定抗拉强度、冲击强度及3点弯曲横向断裂强度,并和常规拉伸试样(DIN EN ISO 2740)的强度与冲击性能进行了对比。结果表明,由同步器齿毂与常规试样测定的数据都在试验误差范围之内,完全一致。为了证实对比的有效性,还用全面的化学与显微组织分析证明了2种试样的相似性。最后,建立了小型拉伸试棒的横向断裂强度与抗拉强度之间的相关性。

关键词：力学性能硬度拉伸性能横向断裂强度

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Review of Matrix Aluminas for Refractory Formulations

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China's Refractories 2015年第1期24卷 57-62页

作者： Andreas BUHR Rainer KOCKEGEY_lorenz Lanyin ZHANG Bin LONG Yunpeng ZHOU Zhongkai TIAN Almatis GmbH Qingdao Almatis Co. Ltd.

Historically,ground calcined aluminas were the first high-alumina matrix products that were used in refractory formulations, in both shaped and unshaped products. At that time the flow properties of castables were enhanced by the use of silica fume. This was followed later by the development of fully ground reactive aluminas which contributed to the design of the matrix below 63 μm. In addition to aggregate fines,a range of bi-modal and multi-modal reactive aluminas were also developed. These not only gave improved physical properties but also better castable workability. This paper reviews matrix alumina developments over time,from basic ground calcines to complex multi-modal matrix products and their globally standardised manufacture.

关键词： matrix fillers reactive alumina porosity strength global product concept

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Assessing the effects of surface-bound humic acid on the phototoxicity of anatase and rutile TiO_2 nanoparticles in vitro

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j.urnal of Environmental Sciences 2016年第4期28卷 50-60页

作者： Xiaoj.a He Sabrieon Sanders Winfred G.Aker Yunfeng Lin j.ssica douglas Huey-min Hwang Department of Biology Jackson State University Department of Biological Sciences Alcorn State University Environmental Science Ph.D.Program Jackson State University Department of Chemistry and Biochemistry Jackson State University School of Polymers and High Performance Materials The University of Southern Mississippi

In this study,the cytotoxicity of two different crystal phases of TiO2 nanoparticles,with surface modification by humic acid（HA）,to Escherichia coli,was *** physicochemical properties of TiO2 nanoparticles were thoroughly *** different initial concentrations,namely 50,100,and 200 ppm,of HA were used for synthesis of HA coated TiO2 nanoparticles（denoted as A/RHA50,A/RHA100,and A/RHA200,respectively）.Results indicate that rutile（LC50（concentration that causes 50%mortality compared the control group）=6.5）was more toxic than anatase（LC50=278.8）under simulated sunlight（SSL）irradiation,possibly due to an extremely narrow band *** is noted that HA coating increased the toxicity of anatase,but decreased that of ***,AHA50 and RHA50had the biggest differences compared to uncoated anatase and rutile with LC50of 201.9 and21.6,*** then investigated the formation of reactive oxygen species（ROS）by TiO2 nanoparticles in terms of hydroxyl radicals（OH）and superoxide anions（O2^-）.Data suggested that O2^- was the main ROS that accounted for the higher toxicity of rutile upon SSL *** also observed that HA coating decreased the generation of OH and O2^- on rutile,but increased O2^- formation on *** from TEM analysis also indicated that HA coated rutile tended to be attached to the surface of *** more than anatase.

关键词： TiO2nanoparticles Escherichia coli Humic acid Crystallinity Surface coating

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Status of IPC-4101F

Status of IPC-4101F

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第十八届中国覆铜板技术·市场研讨会

作者： douglas j.Sober Microtek Changzhou Laboratories

The publication of IPC-4101E released in March 2017 has introduced a tightened definition of contamination that is allowed for copper-clad laminates and prepregs. Otherwise the changes in this revision are minimal. For IPC-4101 Revision F, there are a number of changes that will affect CCL makers world-wide including new specification sheets, introduction of FR-15.0 and FR-15.1, and the new IPC Validation Services certification program. As a primary contributor to IPC-4101 and the Base Materials General Chairman for IPC, Mr. Sober will provide details of these standards and how they will affect the electronics supply chain.

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Plasmonic mid-infrared third harmonic generation in germanium nanoantennas

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Light(Science & Applications) 2018年第1期7卷 19-25页

作者： Marco P.Fischer Aaron Riede Kevin Gallacher j.copo Frigerio Giovanni Pellegrini Michele Ortolani douglas j.Paul Giovanni Isella Alfred Leitenstorfer Paolo Biagioni Daniele Brida Department of Physics and Center for Applied Photonics University of Konstanz78457 KonstanzGermany School of Engineering University of GlasgowRankine BuildingOakfield AvenueGlasgow G128LTUK L-NESS Dipartimento di Fisica del Politecnico di MilanoVia Anzani 4222100 ComoItaly Dipartimento di Fisica Politecnico di MilanoPiazza Leonardo da Vinci 3220133 MilanoItaly Department of Physics Sapienza University of Rome00185 RomeItaly Physics and Materials Science Research Unit University of Luxembourg162a avenue de la FaïencerieL-1511 LuxembourgLuxembourg

We demonstrate third harmonic generation in plasmonic antennas consisting of highly doped germanium grown on silicon substrates and designed to be resonant in the mid-infrared frequency range that is inaccessible with conventional nonlinear plasmonic *** to the near-field enhancement,the result is an ultrafast,subdiffraction,coherent light source with a wavelength tunable between 3 and 5μm,and ideally overlapping with the fingerprint region of molecular *** observe the nonlinearity in this challenging spectral window,a highpower femtosecond laser system equipped with parametric frequency conversion in combination with an all-reflective confocal microscope setup is *** demonstrate spatially resolved maps of the linear scattering cross section and the nonlinear emission of single isolated antenna structures.A clear third-order power dependence as well as mid-infrared emission spectra prove the nonlinear nature of the light *** support the observed resonance length of the double-rod antenna and demonstrate that the field enhancement inside the antenna material is responsible for the nonlinear frequency mixing.

关键词： antenna antennas scattering

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