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Roles of Arabidopsis Patatin-Related Phospholipases A in Root Development Are Related to Auxin Responses and Phosphate Deficiency

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Molecular Plant 2010年第3期3卷 524-538页

作者： Steffen Rietz Georgi Dermendj.ev Esther Oppermann Fikadu Getah Tafesse Yunus Effendi Andre Holk j.ne E. parker Markus Teige Gunther F.E. Scherer Max Planck Institute for Plant Breeding Research Department of Plant Microbe Interactions Carl von Linne Weg 10 D-50829 Cologne Germany Leibniz University Hannover Molecular Developmental Physiology Herrenhauser Str. 2 D-30419 Hannover Germany University of Vienna MFPL Department of Biochemistry Dr. Bohrgasse 9 A-1030 Wien Austria Present address: University of Utrecht Department of Membrane Enzymology Inst. Biomembranes Padualaan 8 NL 3584 CH Utrecht. The Netherlands

Phospholipase A enzymes cleave phospho- and galactolipids to generate free fatty acids and lysolipids that function in animal and plant hormone signaling. Here, we describe three Arabidopsis patatin-related phospholipase A （pPLA） genes AtPLAIVA, AtPLAIVB, and AtPLAIVC and their corresponding proteins. Loss-of-function mutants reveal roles for these pPLAs in roots during normal development and under phosphate deprivation. AtPLAIVA is expressed strongly and exclusively in roots and AtplalVA-null mutants have reduced lateral root development, characteristic of an impaired auxin response. By contrast, AtPLAIVB is expressed weakly in roots, cotyledons, and leaves but is transcriptionally induced by auxin, although AtplalVB mutants develop normally. AtPLAIVC is expressed in the floral gynaecium and is induced by abscisic acid （ABA） or phosphate deficiency in roots. While an AtplalVC-1 loss-of-function mutant displays ABA respon- siveness, it exhibits an impaired response to phosphate deficiency during root development. Recombinant AtPLA proteins hydrolyze preferentially galactolipids and, less efficiently, phospholipids, although these enzymes are not localized in chloroplasts. We find that AtPLAIVA and AtPLAIVB are phosphorylated by calcium-dependent protein kinases in vitro and this enhances their activities on phosphatidylcholine but not on phosphatidylglycerol. Taken together, the data reveal novel functions of pPLAs in root development with individual roles at the interface between phosphate deficiency and auxin signaling.

关键词： Abiotic/environmental stress hormonal regulation protein phosphorylation/dephosphorylation signaltransduction gene regulation Arabidopsis.

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Recovery rates of combination antibiotic therapy using in vitro microdialysis simulating in vivo conditions

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j.urnal of Pharmaceutical Analysis 2018年第6期8卷 407-412页

作者： j.yesh A.Dhanani Suzanne L.parker j.ffrey Lipman Steven C.Wallis j.remy Cohen j.hn Fraser Adrian Barnett Michelle Chew j.son A.Roberts Burns Trauma and Critical Care Research Centre The University of Queensland UQ Centre for Clinical Research Department of Intensive Care Medicine Royal Brisbane & Women's Hospital Faculty of Health Queensland University of Technology Critical Care Research Group The University of Queensland Institute of Health and Biomedical Innovation & School of Public Health and Social Work Queensland University of Technology Department of Anaesthesiology and Intensive Care and Department of Medical and Health Sciences Link?ping University School of Pharmacy The University of Queensland Department of Pharmacy Royal Brisbane & Women's Hospital

Microdialysis is a technique used to measure the unbound antibiotic concentration in the interstitial spaces, the target site of action. In vitro recovery studies are essential to calibrating the microdialysis system for in vivo studies. The effect of a combination of antibiotics on recovery into microdialysate requires investigation. In vitro microdialysis recovery studies were conducted on a combination of vancomycin and tobramycin, in a simulated in vivo model. Comparison was made between recoveries for three different concentrations and three different perfusate flow rates. The overall relative recovery for vancomycin was lower than that of tobramycin. For tobramycin, a concentration of 20μg/mL and flow rate of 1.0μL/min had the best recovery. A concentration of 5.0μg/mL and flow rate of 1.0μL/min yielded maximal recovery for vancomycin. Large molecular size and higher protein binding resulted in lower relative recoveries for vancomycin. Perfusate flow rates and drug concentrations affected the relative recovery when a combination of vancomycin and tobramycin was tested. Low perfusate flow rates were associated with higher recovery rates. For combination antibiotic measurement which includes agents that are highly protein bound, in vitro studies performed prior to in vivo studies may ensure the reliable measurement of unbound concentrations.

关键词： Microdialysis Combination antibiotic therapy Relative recovery rate Pharmacokinetics Anti-infectives Protein binding

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Drought and Associated Impacts in the Great Plains of the United States—A Review

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International j.urnal of Geosciences 2013年第6期4卷 72-81页

作者： j.ffrey B. Basara j.anna N. Maybourn Casey M. Peirano j.nnifer E. Tate parker j. Brown j.ke D. Hoey Brandon R. Smith 1School of Meteorology University of Oklahoma Norman USA 2Oklahoma Climatological Survey University of Oklahoma Norman USA 1School of Meteorology University of Oklahoma Norman USA 2University of Reading Reading UK School of Meteorology University of Oklahoma Norman USA

The Great Plains region of the United States is susceptible to drought of all kinds including meteorological/climatological, agricultural, hydrological, and socioeconomic. Drought conditions in the region span varying spatial and temporal scales and the causes include: 1) certain synoptic conditions that favor drought such as mid-tropospheric ridging over the drought-affected area and a weak low-level j.t;2) sea surface temperature anomalies and associated teleconnections;3) land-atmosphere coupling;and 4) anthropogenic effects. While drought can span as few as a couple of months, the most severe droughts can occur at the decadal scale such as the 1930s Dust Bowl, the worst drought in recent history from a societal standpoint. Such droughts in the Great Plains have widespread impacts on agriculture, water resources, human health, and the economy.

关键词： Drought Great Plains United States Rainfall Precipitation

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Dofasco 厂4#高炉一代炉役超过12年的炉缸管理

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现代冶金（内蒙古） 2002年第2期 25-30页

作者： B.j.parker 陈革等

本文根据Dofasco厂4#高炉第四代炉役的生产实践，对影响高炉长寿的因素进行了分析，并加以改进，从而使其第五代高炉炉役寿命至少达到12年以上。

关键词：高炉炉缸管理炼铁生产实践

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显微腹腔镜的应用

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中华妇产科杂志 2000年第2期35卷 125-126页

作者：朱兰黄胡信 j.m parker j.ff Reid 中国医学科学院澳大利亚新南威尔斯大学利物蒲医院妇产科

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Solids motion in rolling mode rotating drums operated at low to medium rotational speeds

Solids motion in rolling mode rotating drums operated at low...

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CCAST“颗粒物理”研讨会

作者： Y.L.Ding j.P.K.Seville R.Forster D.j.parker School of Chemical Engineering . Positron Imaging Centre University of Birntingham Edgbaston Birmingham B15 2TT. UK School of Chemical Engineering . Positron Imaging Centre University of Birntingham Edgbaston Birmingham B15 2TT. UK School of Physics and Astronomy. Positron Imaging Centre. University of Birmingham. Edgbaston Birmingham B15 2TT UK School of Physics and Astronomy. Positron Imaging Centre. University of Birmingham. Edgbaston Birmingham B15 2TT UK

＜正＞ The industrial-scale rotating drums are usually operated in the rolling or slumping mode. For the rolling mode, the granular material bed can be divided into two regions, namely, a ’passive’ region where particles are carried up by the drum wall, and an ’active’ region where particles cascade down. As solids mixing mainly occurs in the active region, solids motion in this region and solids exchange between the active and passive regions are of prime importance for the overall performance of the drum. This paper reports some observations on particle motion in the transverse plane of a three-dimensional rotating drum operated at low and medium rotational speeds. The non-invasive PEPT （positron emission particle tracking） technique is used to follow particle traj.ctory and velocity. A mathematical model based on the thin-layer approximation is proposed to describe solids motion in the active layer. Reasonable agreement between the model predictions and experiments is obtained. A new parameter termed the ’solids exchange coefficient is proposed to characterise particle exchange between the passive and active regions. A theoretical expression for this parameter is also derived. This expression, upon application of the thin-layer approximation, is reduced to give an explicit relationship between the solids exchange coefficient and drum operating parameters such as rotational speed and fill percentage. as well as the bed material rheological properties. The solids exchange coefficient is also shown to give a possible scale-up rule for rotating drums operated in a rolling mode, 2001 Elsevier Science Ltd. All rights reserved.

关键词： Solids motion Solids mixing Rotating drums Rolling mode PEPT

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Solids motion in bubbling gas fluidised beds

Solids motion in bubbling gas fluidised beds

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CCAST“颗粒物理”研讨会

作者： M.Stein Y.L.Ding j.P.K.Seville D.j.parker School of Chemical Engineering. University of Birmingham. Edgbaston. Birmingham B15 2TT. UK School of Chemical Engineering. University of Birmingham. Edgbaston Birmingham B15 2TT. UK Positron Imaging Centre University of Birmingham. Edgbaston Birmingham B15 2TT. UK School of Chemical Engineering. University of Birmingham. Edgbaston Birmingham B15 2TT. UK Positron Imaging Centre University of Birmingham. Edgbaston Birmingham B15 2TT. UK Positron Imaging Centre University of Birmingham. Edgbaston. Birmingham B15 2TT. UK School of Physics. University of Birmingham Edgbaston. Birmingham B15 2TT. UK

＜正＞ Gas fluidised beds are widely employed in the chemical, petrochemical, metallurgical, and pharmaceutical industries. Solids mixing in such devices plays a central role in controlling product quality and productivity. This paper presents some observations of particle motion in 3-D gas fluidised beds operated in the bubbling mode and at atmospheric pressure. The non-invasive positron emission particle tracking（PEPT） technique was used to observe and quantify particle traj.ctory, solids How pattern,solids velocity, and solids circulation frequency. It is shown that for relatively-deep beds （cylindrical columns, group B particles）, particles move upward in the central region, and downward near the wall. The average upward particle velocity is - 50% of the bubble velocity under the conditions of this study. Theoretical models are proposed to correlate the overall particle upward velocity and average particle velocity in the drift to the bubble velocity, and to estimate the duration of particle residence in the drift. Model predictions show reasonable agreement with experiments. It is suggested that solids motion in gas fluidised beds can be characterised by ’j.mp’, ’idle’ and ’relaxation’ times. These times may also be linked to particle kinetic energy transfer in lluidised beds. 2000 Elsevier Science Ltd. All rights reserved.

关键词： Gas fluidised bed Bubbling bed Solids motion Particle velocity Mixing PEPT

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用非水溶剂回收和精炼银和金

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黄金 1984年第6期 36-37页

作者： A.j.parker 李世谅

引言金在有氧存在条件下溶解于王水、氯、氰化物水溶液或硫脲溶液中,这些溶剂在金的提取冶金过程中起着重要作用。氯化银在水中的溶解度很小,故在处理一些含银的物料时,对某些溶剂的使用造成了困难。例如,氯化银膜的形成和阻碍离子的传... 详细信息

引言金在有氧存在条件下溶解于王水、氯、氰化物水溶液或硫脲溶液中,这些溶剂在金的提取冶金过程中起着重要作用。氯化银在水中的溶解度很小,故在处理一些含银的物料时,对某些溶剂的使用造成了困难。例如,氯化银膜的形成和阻碍离子的传递,使得氯、氯化铁或王水对含银物料的氧化速度减慢。

关键词： DMSO DMF CI 亚砜甲酰胺氯化物氯化银液固萃取化工单元操作浸取

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Granular motion in rotating drums: bed turnover time and slumping-rolling transition

Granular motion in rotating drums: bed turnover time and slu...

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CCAST“颗粒物理”研讨会

作者： Y.L.Ding R.Forster j.P.K.Seville D.j.parker School of Chemical Engineering. University of Birmingham Edgbaston. Birmingham B15 2TT. UK Positron Imaging Centre. University of Birmingham Edgbaston. Birmingham B15 2TT UK Positron Imaging Centre. University of Birmingham. Edgbaston. Birmingham B15 2TT. UK School of Physics and Astronomy University of Birmingham. Edgbuston. Birmingham B15 2TT. UK School of Chemical Engineering. University of Birmingham Edgbaston. Birmingham B15 2TT. UK Positron Imaging Centre. University of Birmingham. Edgbaston. Birmingham B15 2TT. UK Positron Imaging Centre. University of Birmingham. Edgbaston. Birmingham B15 2TT. UK School of Physics and Astronomy University of Birmingham. Edgbuston Birmingham B15 2TT. UK

＜正＞ Theoretical models are presented tor calculation of the bed turnover time in both the slumping and rolling modes and the slumping-to-rolling transition in rotating drums with less than 50% volumetric fill of free-flowing granular materials. It is suggested that the transition from slumping to rolling occurs when the two turnover times arc equal. The model for the bed turnover time in rolling beds is compared with the data reported in the literature. Very good agreement has been obtained. The bed turnover time is also employed to define a new Froude number for constructing the bed behaviour *** is shown that the bed behaviour diagram based on the new Froude number brings the data points for sand and limestone into single curves. The implications of the bed turnover time for solid mixing and heat transfer within particle beds are also discussed. 2002 Elsevier Science B.V. All rights reserved.

关键词： Rotating drums Bed turnover time Solids motion Rolling mode Slumping mode Transition Bed behaviour diagram

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甜味剂的展望

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甜菜糖业 1979年第5期 24-29页

作者： K.j.parker 徐祖健无锡轻工业学院

前言由于全世界的食糖消费逐年扩大和价格增高的原因,促使糖代用品日益引人注意,尤其是对低产热量的糖代用品的需要,更是使国外研究糖代用品的科学工作者,不断地寻求广泛的甜味剂的报导,陆续发表。本文内容主要介绍非蔗糖甜味剂在当前... 详细信息

前言由于全世界的食糖消费逐年扩大和价格增高的原因,促使糖代用品日益引人注意,尤其是对低产热量的糖代用品的需要,更是使国外研究糖代用品的科学工作者,不断地寻求广泛的甜味剂的报导,陆续发表。本文内容主要介绍非蔗糖甜味剂在当前的趋势,以及几种类别的新甜味剂的来源和效能。糖的用途,历来就认为在于改进食物和饮料的口味。在纪元前3000多年古埃及人已知

关键词：甜味剂蔗糖食品添加剂二糖糖代用品甜蜜素环己基氨基磺酸钠

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