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distinct expression profiles of transcriptional coactivators for thyroid hormone receptors during Xenopus laevis metamorphosis

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Cell Research 2003年第6期13卷 459-464页

作者： BINdU d PAUL National Institutes of Health Laboratory of Gene Regulation and development National Institute of Child Health and Human development Bldg. USA.

The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/ NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-l/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are express

关键词： transcription coactivators thyroid hormone receptor Xenopus laevis metamorphosis histone acetylation.

Nanocrystalline and Nanocomposite Magnetic Materials and Their Applications

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Journal of Iron and Steel Research International 2007年第4期14卷 69-74页

作者： Robert d Shull Magnetic Materials Group National Institute of Standards and TechnologyGaithersburg MD 20899MarylandUSA

Nanocrystalline materials can possess bulk properties quite different from those commonly associated with conventional large-grained materials. Nanocomposites, a subset of nanocrystalline materials, in addition have been found to possess magnetic properties which are similar to, but different from, the properties of the individual constituents. New magnetic phenomena, unusual property combinations, and both enhanced and diminished magnetic property values are just some of the changes observed in magnetic nanocomposites from conventional magnetic materials. Here, a description will be presented of some of the exciting new properties discovered in nanomaterials and the magnetic applications envisioned for them.

关键词： nanocomposite ferromagnet magnetoresistance magnetic refrigeration domain imaging

Landslides at Qingjiang River in the downstream Area of Shuibuya dam Site, China

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Journal of China University of Geosciences 2006年第2期17卷 158-162页

作者： Kallen d 项伟 Ehret d Rohn J University of Karlsruhe Department of Applied Geology Faculty of Engineering China University of Geosciences

To enhance the general knowledge of landslides in China, the dAAd （German Academic Exchange Service） is financing an investigative project. As part of this project, at the Qingjiang （清江） River, a 10 km^2 area downstream of the Shuibuya （水布垭） dam site was geologically and geotechnicaUy mapped to gather information concerning landslides and their correlation to lithology, slope angles and texture. The geological mapping contained the characterization of the lithological units. The characterization of the shape of landslides and the classification of rocks into units with similar geotechnical behavior is contained in the geotechnical map. Samples were taken and investigated using X-ray diffraction to identify the clay minerals and geotechnical tests to determine the effective shear angle and cohesion of rocks and soils. Geotechnical mapping showed a close connection between lithology, slope angle and texture concerning the occurrence of landslides. Most landslides occur on the northern bank of the Qingjiang River where the dip angle of the bedding is nearly parallel to the slope, resulting in potential and effective slide planes. On the southern bank only sporadic and small landslides occur because the bedding is antipodal to the slope angle. This pilot work is a base for further and more detailed investigations in this area.

关键词： landslide geotechnical mapping geological mapping shear test and X-ray diffraction Shuibuya dam site.

Nitric oxide(NO) decomposition on catalysts, containing oxides of lanthanum and cerium, supported on γ-alumina

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Journal of Rare Earths 2019年第2期37卷 151-159页

作者： d.Stoyanova P.Georgieva I.Avramova K.Aleksieva d.Marinova d.Mehandjiev Institute of General and Inorganic Chemistry-BAS Institute of Catalysis-BAS

The present work was devoted to study the catalytic activity of lanthanum and cerium oxides separately,deposited on g-alumina in the reaction of decomposition of nitric oxide. The catalyst samples were prepared by the method of impregnation of g-Al_2 O_3 using solutions, containing nitrates of lanthanum and cerium. The prepared samples were calcined for 4 h at temperature 650℃ in an oven in air atmosphere. The catalysts were characterized by: chemical analysis by inductively coupled plasma atomic emission spectrometry(ICP-AES), X-ray diffraction(XRd), X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM) combined with energy-dispersive X-ray spectroscopy(EdS), electron paramagnetic resonance(EPR) and infrared(IR) spectroscopy, as well as measurement of the specific surface area. The results show that the catalysts based on lanthanum oxide and cerium oxide deposited on alumina display high catalytic activity over 60% conversion degree with respect to decomposition of nitric oxide in the absence of reducing agent. In the presence of reducer the activity reaches 90% conversion degree.

关键词： Rare earths Catalysts Catalytic activity decomposition of nitric oxide

Twin Growth and Texture Evolution in an Extruded AM30 Magnesium Alloy during Compression

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Journal of Materials Science & Technology 2014年第9期30卷 884-887页

作者： d.Sarker J.Friedman d.L.Chen department of Mechanical and Industrial Engineering Ryerson University 350 Victoria StreetTorontoOntario M5B 2K3 Canada

The aim of this study was to examine and quantify the growth of extension twins and the associated texture change in an extruded AM30 magnesium alloy during compression along the extrusion direction. Three stages of twin growth with increasing strain were observed due to twin-dislocation interactions, together with increasing texture volume fraction of {1210}〈0001〉 and {01- 10}〈0001〉 components. Stage I was characterized by a relatively slow and gradually accelerating growth. A steady-state twin growth was reached in stage II, where the twin width increased linearly with increasing strain. Stage III twin growth became decelerated, exhibiting a plateau-like character.

关键词： Magnesium alloy Compressive deformation Twinning Twin growth Texture

Monitoring of rhythms in laset speckle data

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Journal of Innovative Optical Health Sciences 2014年第3期7卷 73-82页

作者： d.E.Postnov A.Y.Neganova d.d.Postnov A.R.Brazhe Physics department Saratov State University Astrakhanskaya St.83Saratov 410012Russia Biophysics department Biological FacutyMoscow State UniversityLeninskie Gory 1Building 12119991 MoscowRussia

While the laser speckle imaging(LSI)is a powerful tool for multiple biomedical applications,suchas monitoring of the blood flow,in many cases it can provide additional information when combined with spatio-temporal rhythm *** demonstrate the application of GraphicsProcessing Units(GPU)-based rhythm analysis for the post procesing of LSI data,discuss therelevant structure of GPU-based computations,test the proposed technique on surrogate 3d data,and apply this approach to kidney blood fiow *** with surrogate data demonstrate the ability of the method to extract information about oscillation patterns fromnoisy data,as well as to detect the moving source of the *** analysis of kidney dataallow us to detect and to localize the dymamics arising from autoregulation processes at the levelof individual nephrons(tubuloglomerular feedback(TGF)rhythm),as well as to distinguishbetween the TGF-active and the TGF-silent zones.

关键词： Laser speckle imaging wavelet transform kidney autoregulation.

Optimization Study of the Efficient Spindle

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Journal of Thermal Science 2008年第3期17卷 243-246页

作者： Y.d.Kim d.H.Chun M.S.Kang H.d.Kim Korea Textile Machinery Research Institute School of Textiles Yeungnam University School of Mechanical Engineering Andong National University

In the field of yarn dyeing, the most generally employed method is a type of package dyeing which uses a package of cheese stacked on a spindle made of a perforated tube. Spindles up to now, have been designed without considering the characteristics of dyeing liquid, focusing only on the geometric configuration which cause many problems such as lack of level dyeing. To improve the level dyeing and find the appropriate spindle configuration for the most effective dyeing process, this study examines the spindle flow-field in detail, using a computational method. Flow characteristics inside the spindle have been investigated with varying in porosity, porous diameter and the velocity of the flow. The results show that the total pressure of the flow through the spindle is used to overcome body force. The characteristics of the flow from the porous spindle could also be observed. Based on the results from this study, an effective spindle configuration for level-dyeing has been proposed.

关键词： Porosity Spindle Yarn dyeing Computational Fluid dynamics

Electron Structure and Microwave Absorbing Ability of Flaky FeSiAl Powders

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Journal of Materials Science & Technology 2011年第2期27卷 170-174页

作者： T.d.Zhou d.F.Liang L.J.deng d.C.Luan Xihua University Chengdu 610039China State Key Laboratory of Electronic Thin Films & Integrated devices University of Electronic Science and Technology of ChinaChengdu 610054China

Soft magnetic metallic materials have been widely used for absorbing electromagnetic *** Fe 86 t Si t Al 14（t=9,11,14 and 16） alloys powders were prepared from melt-quenched ribbons by annealing and *** a previous report we discussed the order-disordered structure of this *** this article,we studied their electron *** electron numbers of（111） and（100） plane increase with increasing Si content but Bohr magneton *** permittivity and complex permeability are both decreased with increasing Si content *** lowest value of reflectivity among the four alloys is originated from Fe 70 Si 14 Al *** peak values of reflectivity are all lower than 10 dB,and the absorbing frequency range（R 10 dB） increases from 1 to 2 GHz when t reaches 16.

关键词： Flaky powders Specific saturation magnetism Bohr magneton Absorbing ability

de-twinning and Texture Change in an Extruded AM30 Magnesium Alloy during Compression along Normal direction

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Journal of Materials Science & Technology 2015年第3期31卷 264-268页

作者： d.Sarker J.Friedman d.L.Chen department of Mechanical and Industrial Engineering Ryerson University

Twinning and de-twinning are the salient deformation mechanisms in hexagonal close-packed(hcp)metals. The aim of this study was to examine and quantify the de-twinning process involving a reversible motion of twin boundaries in an extruded AM30 magnesium alloy after re-compression along the normal direction(Nd) of pre-compressed samples along the extrusion direction(Ed). {1012} extension twins were first introduced at a compressive strain of 3.7% along the Ed. The subsequent compressive deformation along the Nd induced a gradual shrinkage of twins with increasing cumulative true strain,and the complete de-twinning occurred at a strain of ~7.7%. The twin width decreased linearly with increasing true strain. Texture measurements verified the rotation of c-axes of hcp unit cells towards the anti-compression direction due to {1012} extension twinning after compression along the Ed, and a gradual return of c-axes to the initial orientation due to twin shrinking or de-twinning during the following compression along the Nd. The {1012} twinning corresponded to the formation of new texture components C{1210} and d{0110} and a decrease in the initial texture components A{0001} and B{0001}, while the twin shrinking or de-twinning was characterized by a gradual vanishing of components C{1210} and d{0110} and an increase in the components A{0001} and B{0001}.

关键词： Magnesium alloy Compressive deformation Twinning d