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Case of Waardenburg Shah syndrome in a family with review of literature

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Journal of Otology 2018年第3期13卷 105-110页

作者： Setty.l.n.Chandra Mohan Department of Otolaryngology and Head and neck Surgery Mahatma Gandhi Memorial Hospital Warangal

Waardenburg syndrome is a rare disease characterized by sensorineural deafness in association with pigmentary defects. Depending on additional symptoms, WS have been classified into four *** syndrome type 4, also called as Waardenburg Shah Syndrome is a very rare congenital disorder with astounding variable clinical expression, characterized by pigmentary abnormalities of the hair(A white forelock of hair, premature graying) and pigmentary changes of the iris such as heterochromia or homochromia irides, sensorineural deafness and Hirschsprung disease. Three genes have been bestowed so far in consociation with EDnRB, EDn3, and SOX10 genes. The pattern of inheritance is multifarious with the SOX10 mutation affiliation with autosomal dominant inheritance whereas the EDnRB and EDn3 genes are passed down in an autosomally recessive pattern.

关键词： Waardenburg Shah Syndrome Hirschsprung disease Dystopia canthorum

Magneto optics and time resolved terahertz spectrocopy

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Chinese Physics B 2018年第7期27卷 112-119页

作者： T Dong Z G Chen n l Wang International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Exploring, manipulating, and understanding new exotic quantum phenomena in condensed-matter systems have gen- erated great interest in the scientific community. Static and time resolved optical spectroscopies after photoexcitations are important experimental tools for probing charge dynamics and quasiparticle excitations in quantum materials. In Syner- getic Extreme Condition User Facility （SECUF）, we shall construct magneto-infrared and terahertz measurement systems and develop a number of ultrafast femtosecond laser based systems, including intense near to mid-infrared pump terahertz probe. In this article, we shall describe several systems to be constructed and developed in the facilities, then present some examples explaining the application of magneto optics and time resolved spectroscopy techniques.

关键词： magneto-optics infrared spectroscopy mid-infrared pump terahertz probe

Stable niO-CeO_(2) nanoparticles with improved carbon resistance for methane dry reforming

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Journal of Rare Earths 2022年第1期40卷 57-62页

作者： Andrea Cárdenas-Arenas Esther Bailón-García Dolores lozano-Castelló Patrick Da Costa Agustín Bueno-lópez Department of Inorganic Chemistry University of AlicanteCarretera de San Vicente s/nE03080AlicanteSpain Sorbonne Universite Institut Jean Le Rond d'AlembertCNRS UMR 71902 place de la gare de ceinture78210Saint Cyr L'EcoleFrance

High surface area mixed oxide 8.7%niO-CeO_(2) nanoparticles(122 m2/g;6-7 nm)were prepared using a reversed microemulsion method,and were tested for dry methane reforming(DRM).The catalytic activity of these nanoparticles remains stable under the severe conditions of DRM(700℃),and they show better carbon resistance than conventional niO-CeO_(2) catalysts prepared without control of the *** activity and selectivity of nanoparticles and reference catalyst are similar,but nanoparticles reduce the accumulation of carbon by 63%during the DRM tests,which is a key feature for this *** and H_(2)-TPR suggest that the improved carbon resistance of the nanoparticles is due to the better interaction and cooperation between niO and CeO_(2) mixed *** nanoparticles,the participation of cerium cations in the redox processes taking place during DRM stabilizes cationic species of *** the contrary,the catalyst prepared without control of the size suffers segregation of ni during DRM reaction,and segregated ni explains the higher catalytic formation of carbon.

关键词： Methane dry reforming nickel Ceria nanoparticle Rare earths

Relationship between HSP90a, nPC2 and l-PGDS proteins to boar semen freezability

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Journal of Animal Science and Biotechnology 2017年第3期8卷 582-591页

作者： Julián Valencia Germán Gómez Walter lópez Henry Mesa Francisco Javier Henao Universidad de Caldas Faculty of Agricultural Sciences A.A. 275 Manizales Caldas Colombia

Background： The purpose of this study was to determine the association of three proteins involved in sperm function on the freezability of porcine semen： the heat shock protein 90 alpha（HSP90a）, the niemann-Pick disease type C2 protein（nPC2）, and lipocalin-type prostaglandin D synthase（l-PGDS）.Six adult boars（each boar was ejaculated three times, 18 in total） were classified by freezability based on the percentage of functionally competent sperm. The male semen with highest freezability（MHF） and the male semen with lowest freezability（MlF） were centrifuged immediately after collection to separate seminal plasma and spermatozoa to make four possible combinations of these two components and to incubate them for 3 h,adjusting the temperature to 17 °C, to freeze them afterwards. The quantification of proteins was performed in two stages： at zero and at 3 h after incubation of the four ***： The spermatozoa × incubation time（IT） interaction only had effect（P 〈 0.01） on HSP90 a levels; this protein increased in seminal plasma, after 3 h of incubation, in larger quantity（P 〈 0.05） in combinations with MlF spermatozoa. In relation with the nPC2 protein, two isoforms of 16 and 19 kDa were identified. The 19 kDa isoform was affected（P 〈 0.01） only by the seminal plasma × IT interaction, with superior values（P 〈 0.01） both at zero and three hours of incubation, in the combinations with MHF seminal plasma; and 16 kDa isoform was affected（P 〈 0.01） only by the IT with reduction after 3 h of incubation. The levels of l-PGDS was affected（P 〈 0.01）only by the spermatozoa × IT interaction, which reduced（P 〈 0.01） in combinations with MlF spermatozoa after 3 h of ***： It is possible to consider that the three proteins evaluated were associated with freezability of boar semen due, especially, to the fact that mixtures with MlF spermatozoa showed greater increase levels of the HSP90 a protein and reduction of l-PGDS in plasma. In addition, the seminal

关键词： Boar freezability HSP90a l-PGDS nPC2 Semen preservation Seminal plasma

Atomic-scale roles of Zn element in age-hardened AlMgSiZn alloys

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Journal of Materials Science & Technology 2021年第11期70卷 105-112页

作者： n.n.Jiao Y.X.lai S.l.Chen P.Gao J.H.Chen Center for High-Resolution Electron Microscopy College of Materials Science&EngineeringHunan UniversityChangsha410082China Electron Microscopy laboratory and International Center for Quantum Materials School of PhysicsPeking UniversityBeijing100871China

Adding alloying elements to improve the performances or the manufacturing processes of Al-Mg-Si alloys has long been a serious issue in developing advanced automotive aluminum *** Zn element,among those promising ones,has demonstrated positive alloying effects on Al-Mg-Si ***,the atomic-scale roles of Zn in an age-hardened Al-Mg-Si-Zn alloy have not been adequately *** atomic-resolution electron microscopy,here we report the precise locations of Zn elements in all hardening precipitates involved and their alloying mechanism at the atomic scale when alloying the *** results show that Zn atoms enter all the major hardening phases to occupy specific featured atomic sites of the original elements,*** Si1 and Mg2 sites in theβ’-2 phase,and modify their crystal structures,interfacial structures and morphologies in characteristic *** is revealed that for theβ’-phase,Zn atoms occupy unique atomic sites,whereas for other phases,they demonstrate similar behaviors as other additive alloying elements such as Ag and Cu do.

关键词： Al-Mg-Si alloy Zn addition Precipitate Electron microscopy

Application of thermally stimulated acoustic emission method to assess the thermal resistance and related properties of coals

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International Journal of Mining Science and Technology 2018年第2期28卷 243-249页

作者： E.A.novikov R.O.Oshkin V.l.Shkuratnik S.A.Epshtein n.n.Dobryakova national University of Science and Technology(MISiS) Moscow 119049Russia

Traditional methods of coal thermal resistance characterization are informative but considerably timeconsuming and require utilization of a complex and expensive equipment. This limits the effectiveness of their application. In this paper, authors experimentally investigated potential application of thermally stimulated acoustic emission method for developing of relatively simple and rapid coals thermal resistance assessment method. Features of thermally stimulated acoustic emission of anthracite, lignites and bituminous coal samples subject to cyclic thermal loading have been experimentally *** the first time, it has been shown that there exists a relationship of such patterns with structural parameters and properties of the coal samples, as well as their thermal resistance. The results indicate the possibility of applying the method of thermally stimulated acoustic emission to control processes of cryogenic disintegration and thermal resistance of fossil coals. The description of the equipment and methodological support needed for the implementation of this method have been provided.

关键词： Acoustic emission Fossil coal Thermal resistance Cryogenic disintegration Structure Properties

Activation Energy of nitriding Medium Carbon Ferromanganese Alloy

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Journal of Iron and Steel Research International 2013年第1期20卷 58-61,78页

作者： Saeed n Ghali Mamdouh M Eissa Micheal l Mishreky Steel Technology Department Central Metallurgical Research and Development Institute (CMRDI)Helwan 11421CairoEgypt

Investigation of some kinetics aspects of the reaction between nitrogen and medium carbon ferromanganese （MC-FeMn） was made. nitriding process of fine medium carbon ferromanganese was carried out at temperature ranging from 973 to 1 223 K and time up to 480 min. nitriding was carried out under nitrogen and hydrogen gas pressures. At temperature of 573 K, hydrogen gas was injected with pressure of about 0.2 MPa followed by injection of nitrogen gas up to 1.2 MPa. Sample mass was 35 g, nitrided in cylindrical chamber with 34 mm in inner diameter and 1 200 mm in length. The change in nitrogen pressure was taken as an indication for nitrogen pickup. The mass gain i.e. nitrogen pickup in kilograms per surface area （m2） was determined by time at different temperatures. nitriding rate constants were calculated and the activation energy of nitriding process was derived from Arrhenius equation. The nitriding rate constant was found to be increased by increasing temperature of the reaction. The activation energy of nitriding process of fine medium carbon ferromanganese at time ranging up to 28 800 s is around 140 kJ/mol. It was found that the rate controlling step of the nitriding process of MC-FeMn is diffusion mechanism.

关键词： nitriding ferromanganese gas solid reaction activation energy

SUPERPlASTICITY OF A WATER-QUEnCHED AnD TEMPERED 40Cr STEEl

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Acta Metallurgica Sinica(English letters) 2004年第5期17卷 682-688页

作者： X.J.Xu G.l.liu l.JShi X.n.Cheng l.Cai SchoolofMechanicalEngineering JiangsuUniversityJiangsu212013China

The superplastic deformation characteristics, of commercial 40Cr (i.e., 5140) steel that was water-quenched only 1 times and subsequent high-temperature tempered, were investigated. The results showed that the 40Cr steel has a fine grain of 10-15μm at room temperature, and exhibits a tensile elongation of 304%, a true flow stress of 89.3MPa and a strain rate sensitivity m-value of 0.227 at the initial strain rate of 1.0×10-3s-1and at the temperature of 750°C. The final fracture is caused by the development of neck. The experimental result of elongation is in good agreement with the theoretically predicated value according to the analytical expression (where ef, m, f, nv and ε is respectively elongation, average strain rate sensitivity, initial geometric defect, average strain hardening sensitivity at constant deformation velocity and average true strain). The fracture surface is intergraular, and superplastic deformation induces an equiaxed and grown grain. Decreasing strain rate increases tensile elongation and strain rate sensitivity m-value. The primary superplastic deformation mechanism is thought to be atom-diffusion-controlled grain boundary sliding.

关键词： superplasticity 40Cr steel quenching medium quenching times Microstructure

U-Pb geochronology and geochemistry of late Palaeozoic volcanism in Sardinia(southern Variscides)

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Geoscience Frontiers 2017年第6期8卷 1263-1284页

作者： l.Gaggero n.Gretter A.langone A.Ronchi Department of Earth Environment and Life SciencesUniversity of GenoaCorso Europa 2616132 GenoaItaly Department of Earth and Environmental Sciences University of PaviaVia Ferrata 127100 PaviaItaly Institute of Geosciences and Earth Resources IGGeCnR Via Ferrata 127100 PaviaItaly

The latest Carboniferous to lower Permian volcanism of the southern Variscides in Sardinia developed in a regional continental transpressive and subsequent transtensile tectonic *** produced a wide range of intermediate-silicic magmas including medium-to high-K calc-alkaline andesites,dacites,and rhyolites.A thick late Palaeozoic succession is well exposed in the four most representative Sardinian continental basins(nurra,Perdasdefogu,Escalaplano,and Seui-Seulo),and contains substantial stratigraphic,geochemical,and geochronological evidence of the area's complex geological evolution from the latest Carboniferous to the beginning of the *** on major and trace element data and lA-ICP-MS U-Pb zircon dating,it is possible to reconstruct the timing of postVariscan *** volcanism records active tectonism between the latest Carboniferous and Permian,and post-dates the unroofing and erosion of nappes in this segment of the southern *** particular,igneous zircon grains from calc-alkaline silicic volcanic rocks yielded ages between299±1 and 288±3 Ma,thereby constraining the development of continental strike-slip faulting from south(Escalaplano Basin)to north(nurra Basin).notably,andesites emplaced in medium-grade metamorphic basement(***,Ogliastra)show a cluster of older ages at 332±12 *** the large uncertainty,this age constrains the onset of igneous activity in the *** new radiometric ages constitute:(1)a consistent dataset for different volcanic events;(2)a precise chronostratigraphic constraint which fits well with the biostratigraphic data and(3)insights into the plate reorganization between laurussia and Gondwana during the late Palaeozoic evolution of the Variscan chain.

关键词： Permian volcanism Sardinia U-Pb geochronology Calc-alkaline volcanism