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Unsupervised learning on scientific ocean drilling datasets from the South China Sea

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Frontiers of earth Science 2019年第1期13卷 180-190页

作者： Kevin C.TSe Hon-Chim CHIU Man-yin TSANG yiliang LI edmund y.LAM Department of earth Sciences The University of Hong KongPokfulamHong KongChina Department of Geography and Centre for Geo-computation Studies Hong Kong Baptist UniversityKowloon TongHong KongChina Department of earth Sciences University of TorontoTorontoON M5S 2M8Canada Department of electrical and electronic engineering The University of Hong KongPokfulamHong KongChina

Unsupervised learning methods were applied to explore data patterns in multivariate geophysical datasets collected from ocean floor sediment core samples coming from scientific ocean drilling in the South China *** to studies on similar datasets,but using supervised learning methods which are designed to make predictions based on sample training data,unsupervised learning methods require no a priori information and focus only on the input *** this study,popular unsupervised learning methods including K-means,self-organizing maps,hierarchical clustering and random forest were coupled with different distance metrics to form exploratory data *** resulting data clusters were externally validated with lithologic units and geologic time scales assigned to the datasets by conventional methods. Compact and connected data clusters displayed varying degrees of correspondence with existing classification by lithologic units and geologic time scales.K-means and self-organizing maps were observed to perform better with lithologic units while random forest corresponded best with geologic time *** study sets a pioneering example of how unsupervised machine learning methods can be used as an automatic processing tool for the increasingly high volume of scientific ocean drilling data.

关键词： machine learning unsupervised learning ODP IODP clustering

Dental and periodontal phenotype in sclerostin knockout mice

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International Journal of Oral Science 2014年第2期6卷 70-76页

作者： Ulrike Kuchler Uwe y Schwarze Toni Dobsak Patrick Heimel Dieter D Bosshardt Michaela Kneissel Reinhard Gruber Department of Oral Surgery Medical University of Vienna Vienna Austria Austrian Cluster for Tissue Regeneration Vienna Austria Department of Oral Surgery and Stomatology School of Dental Medicine University of Berne Berne Switzerland Karl Donath Laboratory for Hard Tissue and Biomaterial Research University Clinic of Dentistry Medical University of Vienna Vienna Austria Ludwig Boltzmann Institute for experimental and Clinical Traumatology in AUVA Research Center Vienna Austria Robert K. Schenk Laboratory of Oral Histology School of Dental Medicine University of Berne Berne Switzerland Musculoskeletal Disease Area Novartis Institutes for BioMedical Research Basel Switzerland Laboratory of Oral Cell Biology School of Dental Medicine University of Berne Berne Switzerland

Sclerostin is a Wnt signalling antagonist that controls bone metabolism. Sclerostin is expressed by osteocytes and cementocytes; however, its role in the formation of dental structures remains unclear. Here, we analysed the mandibles of sclerostin knockout mice to determine the influence of sclerostin on dental structures and dimensions using histomorphometry and micro-computed tomography （μCT） imaging, μCT and histomorphometric analyses were performed on the first lower molar and its surrounding structures in mice lacking a functional sclerostin gene and in wild-type controls, pCT on six animals in each group revealed that the dimension of the basal bone as well as the coronal and apical part of alveolar part increased in the sclerostin knockout mice. No significant differences were observed for the tooth and pulp chamber volume. Descriptive histomorphometric analyses of four wild-type and three sclerostin knockout mice demonstrated an increased width of the cementum and a concomitant moderate decrease in the periodontal space width. Taken together, these results suggest that the lack of sclerostin mainly alters the bone and cementum phenotypes rather than producing abnormalities in tooth structures such as dentin.

关键词： alveolar bone micro-computed tomography mouse periodontium sclerostin tooth

LASeR CLADDeD TiCN COATINGS ON THe SURFACe OF TITANIUM

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Acta Metallurgica Sinica(english Letters) 2007年第3期20卷 210-216页

作者： y.L. yang D. Zhang H.S. Kou C. S. Liu College of Science Northeastern University Shenyang 110004 China College of Material and Metallurgy Northeastern University Shenyang 110004 China

Laser cladded coatings of TiCN were produced on the surface of titanium. To obtain the optimal techniques, several conditions were tested by varying the laser scanning rate. The choice of shielding gas was also studied. The cladded coatings were then evaluated from the surface mechanics point of view based on their microhardness. The microstructure of some interesting samples was investigated by optical micrographs （OM）. The results showed that under the condition of fixed pulse frequency and pulse width, the laser scanning rate and the shielding gas are the main factors influencing the components of coatings. TiCN coatings were decompounded and oxidized during the cladding process in the condition of no shielding gas of N2. X-ray diffraction results indicated that the composite coatings composed of TiCN, TiC, Ti2N, and TiO2 were produced using appropriate techniques. The results indicated that the best condition in terms of the surface microhardness is obtained when the scanning rate is 1.5mm/s, the pulse frequency is 15Hz, the pulse width is 3.0ms, and N2 is chosen as the shielding gas. The microhardness of the composite coatings is about 1331kg · mm^-2, which is about 4 times that of the substrate. The optical micrographs indicated that the cladding zone is made up of TiCN, TiO2 and some interdendritic Ti, but the diffusion zone mainly consists of the dendrites phase, and the cladded depth is about 80μm, which is more than 2 times that of the laser nitrided sample. There were no microcracks or air bubbles in the cladded sample, which was cladded using the above optimal techniques.

关键词： laser cladding TiCN coating titanium

Pathogenesis of fatty liver diseases and hepatocellular carcinoma

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Liver Research 2022年第4期6卷 201-202页

作者： John y.L.Chiang Tiangang Li Integrative Medical Sciences Northeast Ohio Medical UniversityRootstownOHUSA Harold Hamm Diabetes Center Department of PhysiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOKUSA

The prevalence of fatty liver diseases has increased rapidly in recent years to about 25%*** liver diseases are multi-faceted in pathogenesis,disease phenotype,and *** is important to understand disease pathogenesis and mechanism in order to develop effective and safe drug therapy for treating fatty liver *** fatty liver disease(AFLD,or alcohol associ-ated liver disease)and viral hepatitis have been the major causes of liver transplant,liver cancer,and death.

关键词： diseases mechanism. liver

Pressure　Loss　Through　Sharp　180　deg　Turn　in　a　Relatively　Short　Two－Pass　Smooth　and　Rib－Roughened　Channel

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Journal of Thermal Science 1995年第2期4卷 109-116页

作者： C.y. Zhao W.Q. Tao(School of energy and Power engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China) School of energy and Power engineering Xi’an Jiaotong University Xi’an China

The local pressure distributions and resistance coefficients (f1 and f2) through the sharp 180 deg turn in a relatively short (L/De = 4) two-pass smooth and rib-roughened channel were investigated for a Reynolds number range of 1.0 × 103 - 9.0 × 103. The rib pitch-to-height ratios (p/e) were 5,10, and 20. The rib height-to-hydraulic diameter ratios (e/De) were 0.025, 0.050 and 0.10, and the rib angles of attack (α) were 90, 45, 60, -45, and -60 deg. Ribs were installed not only in before and after turn regions but also in turn region. The results show that the resistance coefficients remain approximately constant when Reynolds number is more than 3.0×104. The effects of the rib condguration (rib spacing, rib height, and rib orientation) on the inlet straight duct resistance coefficient (f2) were significant, however, their effects on the overall resistance coefficient (f1) were diluted by the sharp-180 turn. For this relatively short channel (L/De=4), the overall resistance coefficient (f1) was greatly affected by the sharp turn. Correlations for the overall resistance (f1) and inlet straight duct resistance coefficient (f2) are presented.

关键词： resistance cofficient rib-roughened channel.

Formation of Co-implanted Silicon Ultra-Shallow Junctions for Low Thermal Budget Applications

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Chinese Physics Letters 2013年第1期30卷 127-129页

作者： Rehana Mustafa S.Ahmed e.U.Khan Department of Physics International Islamic UniversityIslamabadPakistan Advanced electronics Laboratory Faculty of Engineering&TechnologyInternational Islamic University IslamabadPakistan Center for emerging Sciences Engineering and TechnologyIslamabadPakistan Department of Physics Gomal UniversityD.I.KhanPakistan

We present a systematic study to create ultra-shallow junctions in n-type silicon substrates and investigate both pre-and post-annealing processes to create a processing strategy for potential applications in *** wafers were co-implanted with indium and C atoms at energies of 70 keV and 10 keV,respectively.A carefully chosen implantation schedule provides an abrupt ultra-shallow junction between 17 and 43 nm with suppressed sheet resistance and appropriate retained sheet carrier concentration at low thermal budget.A defect doping matrix,primarily the behavior and movement of co-implant generated interstitials at different annealing temperatures,may be engineered to form sufficiently activated ultra-shallow devices.

关键词： shallow annealing implantation

Features of the Real Structure of Lanthanum Hexaboride Polycrystalline

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Chinese Physics Letters 2001年第7期18卷 942-943页

作者： ZHeNG Shu-Qi MIN Guang-Hui ZOU Zeng-Da yU Pu-Lian HAN Jian-De y.B.Paderno College of Materials Science and engineering Shandong UniversityJi’nan 250061 Institute for Problems of Materials Science National Academy of Sciences of UkraineKiev 03142Ukraine

The Microstructure of lanthanum hexaboride(LaB6)polycrystalline has been studied by using transmission electron *** shows that the ideal LaB6 polycrystalline can be obtained by sintering ingots at the temperature of 2273 K for holding time of 120 min in Ar pressure of 800 Torr,where the ingots are formed by pressing LaB6 powder at room temperature at a pressure of 0.4-0.5 *** particles in LaB6 polycrystalline hardly bind;there are only a few of pores at the joint parts of three particles and a few of impurities exist in some *** sintering process for fabricating LaB6 polycrystalline is analysed and the formation of the pore and the impurities are studied from the point of surface tension.

关键词： LaB6 polycrystalline lanthanum

ectopic expression of neurotrophic peptide derived from saposin C increases proliferation and upregulates androgen receptor expression and transcriptional activity in human prostate cancer cells

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Asian Journal of Andrology 2007年第5期9卷 601-609页

作者： yan Ding Hui-Qing yuan Feng Kong Xiao-yan Hu Kai Ren Jie Cai Xiao-Ling Wang Charles y. e young Department of Biochemistry and Molecular Biology School of Medicine Shandong University Jinan 250012 China Departments of Urology and Biochemistry and Molecular Biology Mayo Graduate School Mayo Clinic Rochester MN55905 USA

Aim： To determine the effects of the functional domain of saposin C （neurotrophic peptide [NP]） on androgen receptor （AR） expression and transcriptional activity. Methods： We constructed DNA vectors expressing NP or a chimeric peptide of the viral TAT transduction domain and NP （TAT-NP） using gene cloning technology. The effects of ectopic expression of NP or TAT-NP on cell growth were examined by 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyl-2H-tetrazolium bromide （MTT） assay. Reverse transcription-polymerase chain reaction （RT-PCR）, Western blot, transient transfection and reporter gene assays were used to determine the effects of NP on AR expression and activation. Results： NP stimulated proliferation of androgen responsive LNCaP cells in the absence of androgens. RT-PCR and Western blot analyses showed that ectopic expression of NP resulted in induction of AR gene expression, and that the NP-stimulated expression of AR could be synergistically enhanced in the presence of androgens. Furthermore, reporter gene assay results showed that NP could enhance AR transactivation by increasing androgen-inducible gene reporter activity. Conclusion： We provided evidence that ectopic expression of saposin C-originated NP could upregulate AR gene expression and activate the AR transcriptional function in an androgen-independent manner in prostate cancer cells.

关键词： neurotrophic peptide, androgen receptor saposin C prostate carcinoma cell lines

Synthesis,Crystal Structure and Conformational Analysis of (e)-5-Methoxy-2-((4-methoxyphenylimino)methyl)phenol

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Chinese Journal of Structural Chemistry 2010年第3期29卷 359-364页

作者： ■AHN Onura ByKGNGR Orhana ALBAyRAK i■demb ODABA■O■LU Mustafac Department of Physics Faculty of Arts and SciencesOndokuz Mayis University Department of Science education Sinop University Chemistry Programme Pamukkale University

The title compound,（e）-5-methoxy-2-（（4-methoxyphenylimino）methyl）phenol（C15H15NO3）,crystallizes in monoclinic,space group P21/c with a=9.4361（6）,b=10.6212（5）,c=12.9338（9）,β=93.064（5）o,V=1294.41（14）3,Z=4,Dc=1.320 g/cm3,F（000）=544,Rint=0.116,T=296 K,μ=0.09 mm-1,the final R=0.051 and wR=0.148 for 1836 observed reflections with I2σ（I）.An extensive two-dimensional network of C–H…O hydrogen bonds and π-ring interactions are responsible for the crystal *** hydrogen bonds and C–H…π interactions produce R22（14）,R44（30） and R44（31） *** addition to the molecular geometry from X-ray experiment,the molecular geometry of the title compound in the ground state has been calculated using the semi-empirical（AM1 and PM3） and density functional theory method（DFT）（B3LyP） with 6-31G（d） basis *** determine the conformational flexibility,molecular energy profile of the title compound was obtained by semi-empirical（PM3 and AM1） and DFT/B3LyP calculations with respect to the selected degree of torsional freedom,which varied from –180° to ＋180° in a step of 10°.

关键词： crystal structure Schiff base PM3 AM1 DFT conformational analysis