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Petrological implication of wagnerite-Ma5bc in the quartzofeldspathic gneiss, Larsemann Hills, East Antarctica

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Progress in Natural Science:Materials International 2005年第6期15卷 523-529页

作者： edward S. GREW 5790 edward T. Bryand Research Center Department of Earth Sciences Maine 04469-5790 Orono USA University of Maine

Wagnerite-Ma5bc polytype is found in a gneiss associated with cordierite-prismatine-bearing gneiss, northern Stornes Peninsula, Larsemann Hills, East Antarctica. Wagnerite coexists with apatite and both of them are present as rock-forming minerals. Ca depletion is not essential to the formation of wagnerite; sufficient Mg, P and F components, and a relatively low Ca/Mg ratio is critical, otherwise only apatite crystallizes. Strong anatexis of the quartzofeldspathic gneiss of the area results in differentiation and separate enrichment of leuco- and melanocratic components. P and F tend to accumulate in the mafic-rich melanocratic component, and when their abundance reaches certain concentration, wagnerite forms. It is perhaps the chemistry of the setting that controls the appearance of wagnerite, whereas the PT condition is responsible for the variety of wagnerite polytype. A disordered polytype crystallizes at relatively high temperature, then cools down slowly and transforms into one of the ordered polytypes, in this case, the Ma5bc polytype.

关键词： wagnerite-Ma5bc polytype anatexis formation condition volatile components Larsemann Hills.

Vascular resection and reconstruction at pancreatico-duodenectomy:technical issues

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Hepatobiliary & Pancreatic Diseases International 2012年第3期11卷 234-242页

作者： edward CS Lai Pedder Clinic 4/F 9 Queen's Road Central

BACKGROUND:With the improvement of perioperative management over the years,pancreatico-duodenectomy has become a safe operation despite its technical *** presence of concomitant visceral artery occlusion unrelated to the underlying malignancy and concomitant major venous infiltration by tumor poses additional hazards to resection which could compromise the postoperative *** SOURCES:A MEDLINE database search was performed to identify relevant articles using the key ords 'median arcuate ligament syndrome','superior mesenteric artery','replaced right hepatic artery',and 'portal vein resection'.Additional papers and book chapters were identified by a manual search of the references from the key ***:Computed tomography with 3-dimensional reconstruction of the vascular anatomy provides most key information on the potential vascular problems encountered during surgery.A trial clamping of the gastroduodenal artery provides a simple intraoperative assessment for the presence of any significant visceral arterial *** on the timing of diagnosis,division of the median arcuate ligament,bypass or endovascular stenting should be *** and superior mesenteric vein resection had been used with increasing frequency and *** steps and methods taken to reconstruct the venous continuity vary with individual surgeons,and the anatomical variations *** segmental loss of the portal vein,opinions differs with regard to the preservation of the splenic vein,and when divided,the necessity of restoring its continuity;source of the autologous vein graft when needed and whether the use of synthetic graft is a safe ***:During a pancreatico-duodenectomy,images of computed tomography must be carefully studied to appreciate the changes and variation of vascular *** preoperative preparation,acute awareness of the probable arterial and venous anatomical variation and the availability of expert

关键词： pancreatico-duodenectomy vein resection celiac axis compression

Advances in shape measurement in the digital world

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Particuology 2016年第3期14卷 19-31页

作者： Xiaodong Jia edward J. Garboczi School of Chemical and Process Engineering University of Leeds Leeds IS2 9JT. UK Material Measurement Laboratory National Institute of Standards and Technology Boulder CO 80305. USA

The importance of particle shape in terms of its effects on the behaviour of powders and other particulate systems has long been recognised, but particle shape information has been rather difficult to obtain and use until fairly recently, unlike its better-known counterpart, particle size. However, advances in computing power and 3D image acquisition and analysis techniques have resulted in major progress being made in the measurement, description and application of particle shape information in recent years. Because we are now in a digital era, it is fitting that many of these advanced techniques are based on digital technology. This review article aims to trace the development of these new techniques, highlight their contributions to both academic and practical applications, and present a perspective for future developments.

关键词： Particle shape Digital methods Shape measurement Spherical harmonics X-ray tomography

Contribution of spontaneous L-type Ca^(2+) channel activation to the genesis of Ca^(2+) sparks in resting cardiac myocytes

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Science China(Life Sciences) 2004年第1期47卷 31-37页

作者： edward G LAKATTA Laboratory of Cardiovascular Sciences National Institute on Aging National Institutes of Health Baltimore MD 21224 USA

Ca2+ sparks are the elementary events of intracellular Ca2+ release from the sar-coplasmic reticulum in cardiac myocytes. In order to investigate whether spontaneous L-type Ca2+ channel activation contributes to the genesis of spontaneous Ca2+ sparks, we used confocal laser scanning microscopy and fluo-4 to visualize local Ca2+ sparks in intact rat ventricular myocytes. In the presence of 0.2 mmol/L CdCI2 which inhibits spontaneous L-type Ca2+ channel activation, the rate of occurrence of spontaneous Ca2+ sparks was halved from 4.20 to 2.04 events/(100 μm·s), with temporal and spatial properties of individual Ca2+ sparks unchanged. Analysis of the Cd2+-sensitive spark production revealed an open probability of-10-5 for L-type channels at the rest membrane potentials (-80 mV). Thus, infrequent and stochastic openings of sarcolemmal L-type Ca2+ channels in resting heart cells contribute significantly to the production of spontaneous Ca2+ sparks.

关键词： Ca2+ sparks, L-type Ca2+ channels, cardiac myocytes, confocal microscopy.

Influences of Catch Crop and Its Incorporation Time on Soil Carbon and Carbon-Related Enzymes

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Pedosphere 2015年第4期25卷 569-579页

作者： Anna PIOTROWSKA-DLUGOSZ edward WILCZEWSKI Department of Soil Science and Soil Protection Division of Biochemistry Faculty of Agriculture and Biotechnology UTP University of Science and Technology Department of Agrotechnology Faculty of Agriculture and Biotechnology UTP University of Science and Technology

Catch crops that are cultivated for green manure play an important role in improving soil properties. A 3-year field experi- ment was conducted to investigate the effect of catch crop （pea, Pisum sativum L.） management, i.e., incorporation of catch crop in October/November （autumn） and March （spring）, and without catch crop （control）, on soil organic carbon （SOC）, microbial biomass carbon （MBC） and the activities of carbon （C）-cycle enzymes, including cellulase （Cel）, β-glucosidase （Glu） and invertase （Inv）. Additionally, soil total nitrogen （TN） and pHKcl were investigated. The catch crop was cultivated from August to October each year during 2008-2010. Soil samples were collected from the field of spring barley （Hordeum vulgate L.） that had been grown after the catch crop. Soil samples for microbial activity determination were taken in March, May, June and August in 2009, 2010 and 2011, while SOC and TN contents as well as pHKc1 were determined in March and August. The chemical properties studied did not show significant changes as influenced by the experimental factors. The use of catch crop significantly increased the MBC content and the activities of C-cycle enzymes compared to the control. When the catch crop was incorporated in spring, a significantly higher MBC content was noted in March and May compared to autumn incorporation. Moreover, the spring incorporation of the catch crop significantly increased the Glu activity （except March）, while the activities of Cel and Inv as well as the rate of soil basal respiration were usually unaffected by the time of catch crop incorporation. Greater microbial biomass and higher enzyme activities in the catch crop-treated soil, compared to the control, indicated that the application of the catch crop as a green manure could be recommended as a promising technique to increase the biological activity of the soil. Since there was no significant effect or no consistent results were obtained related to the time of catch crop

关键词： cellulase β-glucosidase invertase microbial biomass carbon soil basal respiration

Venous thromboembolism prophylaxis in hospitalized elderly patients： Time to consider a ＇MUST＇ strategy

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Journal of Geriatric Cardiology 2011年第2期8卷 114-120页

作者： Kwok M Ho edward Litton Department of Intensive Care Medicine Royal Perth Hospital and School of Population Health University of Western Australia Perth WA 6000 Australia

Venous thromboembolism （VTE） is the commonest cause of preventable death in hospitalized patients. Elderly patients have higher risk of VTE because of the high prevalence of predisposing co-morbidities and acute illnesses. Clinical diagnosis of VTE in the elderly patient is particularly difficult and, as such, adequate VTE prophylaxis is of pivotal importance in reducing the mortality and morbidities of VTE. Omission of VTE prophylaxis is, however, very common despite continuous education. A simple way to overcome this problem is to implement universal VTE prophylaxis for all hospitalized elderly patients instead of selective prophylaxis for some patients only according to individual＇ s risk of VTE. Although pharmacological VTE prophylaxis is effective for most patients, a high prevalence of renal impairment and drug interactions in the hospitalized elderly patients suggests that a multimodality approach may be more appropriate. Mechanical VTE prophylaxis, including calf and thigh compression devices and/or an inferior vena cava filter, are often underutilized in hospitalized elderly patients who are at high-risk of bleeding and VTE. Because pneumatic compression devices and thigh length stockings are virtually risk free, mechanical VTE prophylaxis may allow early or immediate implementation of VTE prophylaxis for all hospitalized elderly patients, regardless of their bleeding and VTE risk. Although the cost-effectiveness of this Multimodality Universal STat （＇MUST＇） VTE prophylaxis approach for hospitalized elderly patients remains uncertain, this strategy appears to offer some advantages over the traditional ＇selective and single-modal＇ VTE prophylaxis approach, which often becomes ＇hit or miss＇ or not implemented promptly in many hospitalized elderly patients. A large clustered randomized controlled trial is, however, needed to assess whether early, multimodality, universal VTE prophylaxis can improve important clinical outcomes of hospitalized elderly patients.

关键词： age bundle of care deep vein thrombosis prevention pulmonary embolism

Regulation of NF-κB signaling by the A20 deubiquitinase

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Cellular & Molecular Immunology 2012年第2期9卷 123-130页

作者： Noula Shembade edward W Harhaj Department of Microbiology and Immunology Sylvester Comprehensive Cancer Center The University of Miami Miller School of Medicine Miami FL 33136 USA

The NF-κB transcription factor is a central mediator of inflammatory and innate immune signaling pathways. Activation of NF-KB is achieved by K63-1inked polyubiquitination of key signaling molecules which recruit kinase complexes that in turn activate the IKB kinase （IKK）. Ubiquitination is a highly dynamic process and is balanced by deubiquitinases that cleave polyubiquitin chains and terminate downstream signaling events. The A20 deubiquitinase is a critical negative regulator of NF-κB and inflammation, since A20-deficient mice develop uncontrolled and spontaneous multi-organ inflammation. Furthermore, specific polymorphisms in the A20 genomic locus predispose humans to autoimmune disease. Recent studies also indicate that A20 is an important tumor suppressor that is inactivated in B-cell lymphomas. Therefore, targeting A20 may form the basis of novel therapies for autoimmune disease and lymphomas.

关键词： A20 inflammation NF-κB ubiquitin

Analysis of Tonal Noise Generating Mechanisms in Low-Speed Axial-Flow Fans

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Journal of Thermal Science 2016年第4期25卷 302-311页

作者： edward Canepa Andrea Cattanei Fabio Mazzocut Zecchin DIME-Universita di Genova via Montallegro 1 1-16145 Genoa Italy

The present paper reports a comparison of experimental SPL spectral data related to the tonal noise generated by axial-flow fans.A nine blade rotor has been operated at free discharge conditions and in four geometrical configurations in which different kinds of tonal noise generating mechanisms are present:large-scale inlet turbulent structures,tip-gap flow,turbulent wakes,and rotor-stator *** measurements have been taken in a hemi-anechoic chamber at constant rotational speed and,in order to vary the acoustic source strength,during low angular acceleration,linear speed *** order to avoid erroneous quantitative evaluations if the acoustic propagation effects are not considered,the acoustic response functions of the different test configurations have been computed by means of the spectral decomposition ***,the properties of the tonal noise generating mechanisms have been *** this aim,the constant-Strouhal number SPL,obtained by means of measurements taken during the speed ramps,have been compared with the propagation ***,the analysis of the phase of the acoustic pressure has allowed to distinguish between random and deterministic tonal noise generating mechanisms and to collect information about the presence of important propagation effects.

关键词： Axial-flow fans Tonal noise Acoustic response

Dirichlet Process Gaussian Mixture Models:Choice of the Base Distribution

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Journal of Computer Science & Technology 2010年第4期25卷 653-664页

作者： Dilan Grür Carl edward Rasmussen Gatsby Computational Neuroscience Unit University College London Department of Engineering University of Cambridge Max Planck Institute for Biological Cybernetics.D-72076 Tubingen

In the Bayesian mixture modeling framework it is possible to infer the necessary number of components to model the data and therefore it is unnecessary to explicitly restrict the number of components. Nonparametric mixture models sidestep the problem of finding the ＂correct＂ number of mixture components by assuming infinitely many components. In this paper Dirichlet process mixture （DPM） models are cast as infinite mixture models and inference using Markov chain Monte Carlo is described. The specification of the priors on the model parameters is often guided by mathematical and practical convenience. The primary goal of this paper is to compare the choice of conjugate and non-conjugate base distributions on a particular class of DPM models which is widely used in applications, the Dirichlet process Gaussian mixture model （DPGMM）. We compare computational efficiency and modeling performance of DPGMM defined using a conjugate and a conditionally conjugate base distribution. We show that better density models can result from using a wider class of priors with no or only a modest increase in computational effort.

关键词： Bayesian nonparametrics Dirichlet processes Gaussian mixtures