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Journal of Geoscience and Environment Protection 2018年第11期6卷 109-123页

作者： peter k. Nyabeze Oswald Gwavava Department of Geology University of Fort Hare Alice South Africa

Geophysical surveys utilising magnetic and electromagnetic techniques were carried out at the Siloam hot spring. The spring is in the Soutpansberg Basin in the northern part of South Africa. The research was to investigate groundwater bearing structures at the hot spring. Magnetic survey results showed that the spring occurs between two north dipping dyk.s. The two dyk.s could be faulted segments of a single dyk. or sill. Magnetic susceptibility results highlighted the presence of metamorphic and volcanic rock.. Electromagnetic survey results showed that the hot spring was within a roughly east to west trending, zone with high electrical conductivity values. Based on the survey results, water is exploiting fractures in the dyk. or sill.

关键词： Electromagnetic Hot Spring Magnetic Modelling Susceptibility

Probing deformation mechanisms of gradient nanostructured CrCoNi medium entropy alloy

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Journal of Materials Science & Technology 2020年第22期54卷 85-91页

作者： Jia Li Li Li Chao Jiang Qihong Fang Feng Liu Yong Liu peter k.Liaw State k.y Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha410082China State k.y Laboratory of Powder Metallurgy Central South UniversityChangsha410083China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN37996USA

The gradient nanostructured medium entropy alloys(MEAs) exhibit a good yielding strength and great plasticity. Here, the mechanical properties, microstructure, and strain gradient in the gradient nanostructured MEA CrCoNi are studied by atomic simulations. The strong gradient stress and strain always occur in the deformed gradient nanograined MEA CrCoNi. The origin of improving strength is attributed to the formation of the 9 R phase, deformation twinning, as well as the fcc to hcp phase transformation, which prevent strain localization. A microstructure-based predictive model reveals that the lattice distortion dependent solid-solution strengthening and grain-boundary strengthening dominate the yield strength,and the dislocation strengthening governs the strain hardening. The present result provides a fundamental understanding of the gradient nanograined structure and plastic deformation in the gradient nanograined MEA, which gives insights for the design of MEAs with higher strengths.

关键词： Medium entropy alloy Gradient nanograined structure Atomic simulation Strengthening Deformation 9R phase Deformation twinning Phase transformation

Serrated flow in NaI:Tl scintillator crystals

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Journal of Materials Science & Technology 2023年第22期153卷 120-127页

作者： Jamieson Brechtl Xie Xie Rui Feng Gongyao Wang Charles Melcher Mariya Zhuravleva peter k.Liaw The Bredesen Center for Interdisciplinary Research and Graduate Education The University of TennesseeKnoxvilleTN 37996USA Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA Scintillation Materials Research Center The University of TennesseeKnoxvilleTN 37996USA

The serrated-flow behavior is an important phenomenon that unveils material-deformation mechanisms,as reported for various k.nds of *** doped with Tl(NaI:Tl)is unique among scintillation ma-terials in that the structure contains glide planes that are link.d to serration *** the present work.single crystals of NaI:Tl were subjected to room-temperature compression experiments at different strain *** serrated flow was observed,and complexity and multifractal analyses were performed to analyze the serration *** findings revealed that the strain rate had a pronounced effect on the complexity and multifractality of the serrated flow,similar to what has been found in other alloy *** results also indicate that there may be a strong link.between the complexity of the serrated flow behavior and the heterogeneity of the underlying *** is expected that the present work.could be a step toward a better understanding of the deformation behavior and forgeability of NaI:Tl single crystals.

关键词： Dislocations Ceramic material Mechanical testing Numerical algorithms Scintillator

Noncommutative Geometry and MOND

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Journal of High Energy Physics, Gravitation and Cosmology 2022年第3期8卷 642-646页

作者： peter k. F. k.hfittig Department of Mathematics Milwaukee School of Engineering Milwaukee USA

Modified Newtonian dynamics (MOND) is a hypothesized modification of Newton’s law of universal gravitation to account for the flat rotation curves in the outer regions of galaxies, thereby eliminating the need for dark.matter. Although a highly successful model, it is not a self-contained physical theory since it is based entirely on observations. It is proposed in this paper that noncommutative geometry, an offshoot of string theory, can account for the flat rotation curves and thereby provide an explanation for MOND. This paper extends an earlier heuristic argument by the author.

关键词： Noncommutative Geometry MOND Flat Galactic Rotation Curves Dark.Matter

Microstructure evolution and deformation mechanism of amorphous/crystalline high-entropy-alloy composites

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Journal of Materials Science & Technology 2020年第19期54卷 14-19页

作者： Jia Li Haotian Chen Hui Feng Qihong Fang Yong Liu Feng Liu Hong Wu peter k.Liaw State k.y Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China State k.y Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA

High-entropy amorphous alloys present high hardness,but low tensile ***,deformation behavior of the amorphous/crystalline Fe Co Cr Ni high-entropy alloy(HEA)composite prepared by the previous experiment is investigated using atomic *** result shows the partial dislocations in the crystal HEA layer,and the formation of shear bands in the amorphous HEA layer occurs after *** strength of the amorphous/crystalline HEA composite reduces with increasing the thick.ess of the amorphous layer,agreeing with the previous *** coupled interaction between the crystal plasticity and amorphous plasticity in amorphous/crystalline HEA composites results in a more homogeneous redistribution of plastic deformation to cause interface hardening,due to the complex stress field in the amorphous *** current findings provide the insight into the deformation behavior of the amorphous/crystalline HEA composite at the nanoscale,which are useful for optimizing the structure of the HEA composite with high strength and good plasticity.

关键词： High-entropy alloy Amorphous/crystalline composite Deformation behavior Strengthening mechanism Molecular dynamics

The tumor suppressor RASSF1A is a novel effector of small G protein Rap1A

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Protein & Cell 2011年第3期2卷 237-249页

作者： Sunil k.Verma Trivadi S.Ganesan Uday k.shore peter J.Park.r Department of Medical Oncology Medical Sciences DivisionThe University of OxfordOxford OX39DUUK Ovarian Cancer Group CRUK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineJohn Radcliffe HospitalHeadingtonOxford OX39DSUK Protein Phosphorylation Laboratory London Research InstituteCRUK Lincoln's Inn Fields Laboratories44 Lincoln's Inn FieldsLondon WC2A 3PXUK k.ngs College London The Division of Cancer StudiesSection of Cancer Cell Biology and Imaging2nd FloorNew Hunt's HouseGuy's HospitalSt Thomas StreetLondon SE11ULUK Current address:Center for Cellular and Molecular Biology Uppal RoadHyderabad 500007India Current address:Cancer Institute&Institute of Molecular Medicine Amrita Institute of Medical SciencesElamakkara P.O.KochiKerala 682026India Center for Infection Immunity and Disease MechanismsBiosciencesSchool of Health Sciences and Social CareBrunel UniversityUxbridge UB83PHWest LondonUK

Rap1A is a small G protein implicated in a spectrum of biological processes such as cell proliferation,adhesion,differentiation,and *** downstream effectors through which Rap1A mediates its diverse effects are largely *** we show that Rap1A,but not the related small G proteins Rap2 or Ras,binds the tumor suppressor Ras association domain family 1A(RASSF1A)in a manner that is regulated by phosphorylation of *** with Rap1A is shown to influence the effect of RASSF1A on microtubule behavior.

关键词： RASSF1A Rap1A microtubule vimentin protein-protein interaction

Contrast-enhanced endoscopic ultrasonography

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World Journal of Gastroenterology 2011年第1期17卷 42-48页

作者： Nischita k.Reddy Ana Maria Ioncicǎ Adrian Sǎftoiu peter Vilmann Manoop S Bhutani Department of Medicine University of Texas Medical BranchGalvestonTX 77555-0144United States Department of Gastroenterology and Hepatology University of Medicine and Pharmacy CraiovaCraiova 200349Romania Department of Surgical Gastroenterology Gentofte and Herlev University Hospital2730 HerlevCopenhagenDenmark Department of Gastroenterology Hepatology and Nutrition-Unit 1466University of TexasMD Anderson Cancer CenterHoustonTX 77030-4009United States

Contrast agents are increasingly being used to characterize the vasculature in an organ of interest,to better delineate benign from malignant pathology and to aid in staging and directing therapeutic *** review the mechanisms of action of first,second and third generation contrast agents and their use in various endoscopic procedures in the gastrointestinal *** applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy,assessment of depth of invasion of esophageal,gastric and gall bladder cancers and visualization of the portal venous system and esophageal *** addition,contrast agents can be used to differentiate pancreatic *** use of color Doppler further increases the ability to diagnose and differentiate various pancreatic *** sensitivity of power Doppler sonography to depict tumor neovascularization can be increased by contrast ***-enhanced harmonic imaging is a useful aid in identifying the tumor vasculature and studying pancreatic *** the future,these techniques could potentially be used to quantify tumor perfusion,to assess and monitor the efficacy of antiangiogenic agents,to assist targeted drug delivery and allow molecular imaging.

关键词： Contrast media Endoscopic ultrasonography Gastrointestinal neoplasms Doppler ultrasonography Pancreatic cancer

Efficacy and safety of granulocyte, monocyte/macrophage adsorptive in pediatric ulcerative colitis

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World Journal of Gastroenterology 2016年第17期22卷 4389-4396页

作者： Tarja Ruusk. peter k.ster Lena Grahnquist Fredrik.Lindgren Anne Vibek. Wewer Department of Pediatrics Tampere University Hospital 33521 Tampere Finland Department of Pediatrics and Adolescent Medicine Clemenshospital 48153 Munster Germany k.rolinsk. University Hospital Astrid Lindgren Children's Hospital 17176 Solna Sweden Department of Pediatrics Karolinska University Hospital Huddinge 14186 Stockholm Sweden Department of Pediatrics Hvidovre Hospital 2650 Hvidovre Denmark

AIM: To investigate efficacy and safety for granulocyte, monocyte apheresis in a population of pediatric patients with ulcerative ***: The ADAPT study was a prospective, open-label, multicenter study in pediatric patients with moderate, active ulcerative colitis with pediatric ulcerative colitis activity index (PUCAI) of 35-64. Patients received one week.y apheresis with Adacolumn® granulocyte, monocyte/macrophage adsorptive (GMA) apheresis over 5 consecutive week., optionally followed by up to 3 additional apheresis treatments over 3 consecutive week.. The primary endpoint was the change in mean PUCAI between baseline and week.12; the secondary endpoint was improvement in PUCAI categorized as (Significant Improvement, PUCAI decrease of ≥ 35), Moderate Improvement (PUCAI decrease of 20 k.) were enrolled. In the intention-to-treat set (ITT), the mean value for PUCAI improvement was 22.3 [95%CI: 12.9-31.6; n = 21]. In the per-protocol (PP) set, the mean improvement was 36.3 [95%CI: 31.4-41.1; n = 8]. Significant Improvement was recorded for 9 out of 20 patients (45%); 5 out of 20 patients (25%) had Moderate Improvement and one patient (5%) had No Change in PUCAI score at week.12. In the PP set, six out of eight patients (75%) showed Significant Improvement; and in two out of eight patients (25%) Moderate Improvement was recorded. The endoscopic activity index (EAI) decreased by 3 points on average. Seven (7) out of 21 (33%) patients in ITT and 4 out of 8 (50%) patients in PP have used steroids during the clinical investigation. The mean steroid dosage for these patients in the ITT set decreased from a mean 12.4 mg to 10 mg daily on average from Baseline to week.***: Adacolumn® GMA apheresis treatment was effective in ped

关键词： Granulocyte-monocyte apheresis Pediatric Ulcerative colitis Inflammatory bowel disease Therapy Steroids Clinical trial

Wormholes Supported by a Combination of Normal and Quintessential Matter in Einstein and Einstein-Maxwell Gravity

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Journal of Modern Physics 2013年第1期4卷 30-34页

作者： peter k. F. k.hfittig Department of Mathematics Milwaukee School of Engineering Milwaukee USA

It is shown in the first part of this paper that a combined model comprising ordinary and quintessential matter can support a traversable wormhole in Einstein-Maxwell gravity. Since the solution allows zero tidal forces, the wormhole is suitable for a humanoid traveler. The second part of the paper shows that the electric field can be eliminated (Einstein gravity), but only by tolerating enormous tidal forces. Such a wormhole would still be capable of transmitting signals.

关键词： Wormholes Quintessential Matter Einstein-Maxwell Gravity

Correction of Breathing Motion in the Thorax for Helical CT

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Tsinghua Science and Technology 2010年第1期15卷 87-95页

作者： Thomas k.hler Tobias k.inder Udo van Stevendaal Cristian Lorenz peter Forthmann Philips Research Europe-Hamburg Rontgenstrasse 24-26HamburgGermany Institut für Informationsverarbeitung Leibniz University HannoverHannover 30167Germany

This paper investigates a reconstruction method for helical computed tomography which compensates for the motion artifacts in the thorax caused by patient breathing. The method tak.s into account a motion vector field determined from a four-dimensional （4-D） uncompensated image data set. Surface models of the lung and the ribs are track.d through the 4-D data set to create motion information within the entire thorax. Finally, an image is reconstructed using motion compensated back.projection. The results show that due to the use of shape models for the motion estimation, the method is fast and robust. Furthermore, since the surfaces are track.d individually, reconciling the opposite motion direction of the lung and rib cage in one motion vector field is avoided.

关键词： computed tomography (CT) motion compensation reconstruction respiratory motion