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国际医学放射学杂志 2013年第3期 287-288页

作者： J.Y.Choo C.m.Park n.K.Lee S.m.Lee H.J.Lee J.m.Goo 张业坡 Department of Radiology Seoul National University College of Medicineand Institute of Radiation MedicineSeoul National University Medical Research Center

目的总结运用锥形束CT(CBCT)虚拟导航引导系统进行105例肺部小结节(≤1cm)病人经皮穿刺活检(PCnB)的初步经验。方法运用CBCT虚拟导航引导系统对连续的105例病人(男55例,女50例,平均年龄62岁)的107个肺小结节[≤1cm,平均大小为(0.85±0.1... 详细信息

目的总结运用锥形束CT(CBCT)虚拟导航引导系统进行105例肺部小结节(≤1cm)病人经皮穿刺活检(PCnB)的初步经验。方法运用CBCT虚拟导航引导系统对连续的105例病人(男55例,女50例,平均年龄62岁)的107个肺小结节[≤1cm,平均大小为(0.85±0.14)cm]进行了活检。评估内容包括辐射剂量、敏感度、特异度、诊断准确度及活检并发症。结果同轴针穿破胸膜的次数、活检次数、CT扫描次数、整个活检过程持续时间、同轴针体内停留时间以及穿刺过程估计的射线剂量分别平均为1.03±0.21、3.1±0.7、3.4±1.3、(10.5±3.2)min、(7.2±2.5)min和(5.72±4.19)mSv。60个结节(56.1%)为恶性肿瘤;38个为良性(35.5%)和9个(8.4%)为不确定。CBCT虚拟引导下肺小结节穿刺活检的敏感度、特异度和诊断准确度分别为96.7%(58/60)、100%(38/38)和98.0%(96/98)。发生并发症13例(12.1%),其中气胸7例(6.5%),咯血6例(5.6%)。结论肺小结节(≤1cm)的CBCT虚拟引导下的PCnB是一种高度准确和安全的诊断方法。要点①CBCT虚拟导航引导提供了新的活检肺结节的选项。②CBCT虚拟导航引导下小结节(≤1cm)的PCnB是非常准确的。③CBCT虚拟导航引导下小结节(≤1cm)的PCnB是安全的。④CBCT虚拟导航引导下PCnB的操作时间和辐射剂量是合理的。

关键词： C-臂锥形束CT 虚拟导航引导肺活检肺小结节准确性

Weave geometry generation avoiding interferences for mesoscale RVEs

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Journal of materials Science & Technology 2019年第12期35卷 2869-2882页

作者： Daniel Höwer Shengkai Yu Trenton m.Ricks Brett A.Bednarcyk Evan J.Pineda Bertram Stier Stefanie Reese Jaan-Willem Simon Institute of Applied mechanics RWTH Aachen University52074 AachenGermany nASA Glenn Research Center ClevelandOH 44135USA Collier Research and Development Corporation Newport NewsVA 23606USA

An algorithm which allows the generation of representative volume elements(RVEs) for complex woven and warp-interlaced fiber-reinforced composite topologies while avoiding unphysical tow intersections is presented. This is achieved by extending an existing RVE generation strategy in two significant ways:(1) the local cross section shape of the tow is adjusted depending on the local tow curvature in a way that preserves the cross sectional area of the tow, and(2) the elementary crimp interval is separated into a planar and a transition region. The modifications facilitate the generation of a wide range of elaborate textile topologies without tow intersections, which are present without the proposed modifications unless complex tow to tow contact models are introduced. The mechanical properties of plain weaves were predicted based on the topology generated with the proposed algorithm as well as based on RVEs which were constructed based on actual micrographs, i.e. a "digital twin" of the actual microstructure. A comparison of the predicted mechanical properties based on finite element and multiscale Generalized method of Cells techniques shows close agreement. However, some differences exist with respect to experimentally determined material parameters due to the finite dimensions of the specimens. Lastly,mechanical properties of multilayered weaves are predicted with the finite element method. The considered material systems are carbon fiber in epoxy matrix as well as C/C-sic. However, the procedure is applicable to a wide range of material systems.

关键词： RVE generation multiscale analysis Composites

High-throughput reaction engineering to assess the oxidation stability of mAX phases

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npj Computational materials 2021年第1期7卷 20-32页

作者： D.Sauceda P.Singh A.R.Falkowski Y.Chen T.Doung G.Vazquez m.Radovic R.Arroyave Department of materials Science & Engineering Texas A&M UniversityCollege StationTX 77843USA Department of mechanical Engineering Texas A&M UniversityCollege StationTX 77843USA Ames Laboratory US Department of EnergyIowa State UniversityAmesIA50011USA

The resistance to oxidizing environments exhibited by some mn+1AXn(mAX)phases stems from the formation of stable and protective oxide layers at high operating *** mAX phases are hexagonally arranged layered nitrides or carbides with general formula m_(n+1)AX_(n),n=1,2,3,where m is early transition elements,A is A block elements,and X is C/*** attempts to model and assess oxide phase stability in these systems has been limited in scope due to higher computational *** address the issue,we developed a machine-learning driven high-throughput framework for the fast assessment of phase stability and oxygen reactivity of 211 chemistry mAX phase m_(2)*** proposed scheme combines a sure independence screening sparsifying operator-based machine-learning model in combination with grand-canonical linear programming to assess temperaturedependent Gibbs free energies,reaction products,and elemental chemical activity during the oxidation of mAX *** thermodynamic stability,and chemical activity of constituent elements of Ti_(2)AlC with respect to oxygen were fully assessed to understand the high-temperature oxidation *** predictions are in good agreement with oxidation experiments performed on Ti_(2)*** were also able to explain the metastability of Ti_(2)sic,which could not be synthesized experimentally due to higher stability of competing *** generality of the proposed approach,we discuss the oxidation mechanism of Cr_(2)*** insights of oxidation behavior will enable more efficient design and accelerated discovery of mAX phases with maintained performance in oxidizing environments at high temperatures。

关键词： stability mAX maintained

Sonographic evaluation of the post-operative rotator cuff: Does tendon thickness matter?

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Open Journal of Clinical Diagnostics 2013年第3期3卷 78-84页

作者： J. Lasbleiz T. Benkalfate J. n. morelli J. Jan Orthopaedic Department Clinique Mutualiste La Sagesse 4 Place Saint Guénolé Rennes France Radiology Department Clinique Mutualiste La Sagesse 4 Place Saint Guénolé Rennes France Sport medicine Department Clinique Mutualiste La Sagesse 4 Place Saint Guénolé Rennes France Texas A&m Health Sciences Center Temple USA

The goal of this work is to determine whether sonographic measures of tendon thickness correlate with post-operative functional parameters or re-tear rates. 53 consecutive patients with supraspinatus tears on mRI were examined by an orthopedic surgeon to determine: pre-and post-operative patient pain (via Constant-murley scale), night time pain, maximum force production by the affected arm (in pounds), and range of motion deficits. Post-operative ultrasound at 3 and 12 months following surgery was performed to evaluate for recurrent tear and to measure tendon thickness. Post-operative tendon thickness was inversely related to patient age (r = -0.24;p value of tendon thickness. Post-operative tendon thickness did not successfully predict post-operative functional outcomes or pain levels (p > 0.05). normal post-operative tendon thickness of the rotator cuff decreases from 3 to 12 months following surgery. Thickness is reduced in patients with more severe tears and in older patients but does not correlate with post-operative patient pain or functional outcomes.

关键词： Rotator Cuff Sonography Postoperative Imaging Arthroscopy Postoperative Evaluation

Spinal cord injury reprograms muscle fibroadipogenic progenitors to form heterotopic bones within muscles

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Bone Research 2022年第2期10卷 310-325页

作者： Hsu-Wen Tseng Dorothée Girard Kylie A.Alexander Susan m.millard Frédéric Torossian Adrienne Anginot Whitney Fleming Jules Gueguen marie-Emmanuelle Goriot Denis Clay Beulah Jose Bianca nowlan Allison R.Pettit marjorie Salga François Genêt marie-Caroline Le Bousse-Kerdilès Sébastien Banzet Jean-Pierre Lévesque mater Research Institute-The University of Queensland WoolloongabbaQLDAustralia Institut de Recherche Biomédicale des armées(IRBA) INSERM UMRS-MD1197 ClamartFrance InSERm UmRS-mD 1197 Universitéde Paris-SaclayHôpital Paul BrousseVillejuifFrance InSERm UmS-44 Universitéde Paris-SaclayHôpital Paul BrousseVillejuifFrance UPOH(UnitéPéri Opératoire du Handicap Perioperative Disability Unit)Physical and Rehabilitation Medicine departmentRaymond-PoincaréHospitalAssistance Publique-Hôpitaux de Paris(AP-HP)GarchesFrance Universitéde Versailles Saint Quentin en Yvelines UFR Simone Veil-SantéEND:ICAP INSERM U1179Montigny le BretonneuxFrance

The cells of origin of neurogenic heterotopic ossifications(nHOs), which develop frequently in the periarticular muscles following spinal cord injuries(SCIs) and traumatic brain injuries, remain unclear because skeletal muscle harbors two progenitor cell populations: satellite cells(SCs), which are myogenic, and fibroadipogenic progenitors(FAPs), which are mesenchymal. Lineage-tracing experiments using the Cre recombinase/Lox P system were performed in two mouse strains with the fluorescent protein Zs Green specifically expressed in either SCs or FAPs in skeletal muscles under the control of the Pax7 or Prrx1 gene promoter, respectively. These experiments demonstrate that following muscle injury, SCI causes the upregulation of PDGFRα expression on FAPs but not SCs and the failure of SCs to regenerate myofibers in the injured muscle, with reduced apoptosis and continued proliferation of muscle resident FAPs enabling their osteogenic differentiation into nHOs. no cells expressing Zs Green under the Prrx1 promoter were detected in the blood after injury, suggesting that the cells of origin of nHOs are locally derived from the injured muscle. We validated these findings using human nHO biopsies. PDGFRα+mesenchymal cells isolated from the muscle surrounding nHO biopsies could develop ectopic human bones when transplanted into immunocompromised mice, whereas CD56+myogenic cells had a much lower potential. Therefore, nHO is a pathology of the injured muscle in which SCI reprograms FAPs to undergo uncontrolled proliferation and differentiation into osteoblasts.

关键词： progenitor injuries muscles

需制定统一标准评价肛门直肠畸形患者中相关的先天性异常

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世界核心医学期刊文摘（儿科学分册） 2005年第4期1卷 58-59页

作者： Ratan S. K. Rattan K. n. Pandey R. m. 王经伟 Department of Paediatric Surgery Pt B. D. Sharma PGIMS Tohtak Haryana India

背景/目的:比较高位和低位肛门直肠畸形(arm)患者其他相关畸形的发生率,研究这些共存的畸形,对其发生率与现存文献记载进行比较。方法:对10年来(1993年1月至2002年12月)本中心的416例arm患者的资料进行评价。根据放射学检查或术中所见。

关键词：肛门直肠畸形先天性异常提肌肠道畸形放射学检查中高位生殖器畸形陷窝发育异常 genital

凝固工艺参数对AlniBi合金干滑动磨损行为的影响

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Transactions of nonferrous metals Society of China 2020年第3期30卷 582-594页

作者： T.m.BOTELHO H.m.AZEVEDO G.H.mACHADO C.R.BARBOSA F.S.ROCHA T.A.COSTA O.L.ROCHA Federal Institute of Education Science and Technology of ParáIFPAAlmirante Barroso Avenue 115566093-020 BelémPABrazil Institute of Technology Federal University of ParáUFPAAugusto Correa Avenue 166075-110 BelémPABrazil

对经水平定向凝固制备的Al-3%ni-1%Bi合金(质量分数,%)铸态样品进行微磨料磨损试验,研究凝固热学参数(生长速率(VL)和冷却速率(TR))以及显微组织参数(晶胞间距(λ1)和枝晶间距(λc))对合金耐磨性的影响。摩擦学参数为磨损量(Vw)和磨损速... 详细信息

对经水平定向凝固制备的Al-3%ni-1%Bi合金(质量分数,%)铸态样品进行微磨料磨损试验,研究凝固热学参数(生长速率(VL)和冷却速率(TR))以及显微组织参数(晶胞间距(λ1)和枝晶间距(λc))对合金耐磨性的影响。摩擦学参数为磨损量(Vw)和磨损速率(Rw)。分别利用水冷式水平定向凝固装置和固定旋转式磨球机进行凝固试验和磨损试验。结果表明,具有较细显微组织的样品具有较低的Vw和Rw值。Vw和λ1之间的关系可以用实验数学方程表示。Bi软颗粒和Al3ni硬金属间化合物颗粒在更细的枝晶间分布较好,因此,具有枝晶组织比具有晶胞组织的铸态样品具有更好的耐磨性,可观察到磨损机理由粘着磨损向磨粒磨损转变。

关键词：非稳态水平凝固干滑动磨损晶胞/枝晶间距显微硬度 Bi颗粒 Al_(3)ni颗粒

STUDY On STRUCTURE AnD PROPERTIES OF ni-W-sic COmPOSITE COATInG

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Acta metallurgica Sinica(English Letters) 1997年第5期10卷 419-424页

作者： K. Y ma Z.C. Guo m.F. Wen X. W Yang and F. Han ( Kunming University of Science and Technology, Kunming 650093, China China national nonferrous metals Imp. & Exp. Corp., Shanxi Company, Xi’an 710000, China ) Kunming Univ of Science and Technology Kunming China

The effects of electroplating conditions on the composition of n-W-sic composite coating were studied; the znfiuence of heat-treatment and nitrocarburization on the microstructure, hardness and wear resistance of the coating were discussed. The results showed that an amorphous composite coating, containing(wt%) 50-55ni, *** and 3.0-7.6sic, could be electroplated on the matrix. Afier heat-treatment or nitrocarburization the coating crystallized to form some new phases, and the haordness and wear resistance of the composite coating were enhanced retmarkably.

关键词： electroplating ni-W-sic composite coating heat-treatment nitrocarburization

Evolution of the East Asian monsoon inferred from environmental magnetic record from Lake Biwa,central Japan

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地球环境学报 2011年第1期 313-313页

作者： Hayashida A Yamamoto T Yasuda m Tanigawa Y Ishikawa n Kitagawa H Torii m Haraguchi T Takemura K Affiliated Institution Doshisha University Institute of Geothermal Sciences Kyoto University

Lake Biwa,located in central Japan,contains a thick sedimentary sequence deposited in lacustrine or fluvial environments during the *** and magnetostratigraphic analysis of deep-drilling cores from the central basin showed that about 800 m thick sediment has been deposited for the last 1.3 *** uppermost 250 m clay unit has provided important paleoclimate records,which can be correlated to major glacial-interglacial cycles for the last 0.45 ***,the Lake Biwa sediment is expected to offer detailed records of Asian monsoon activity from the middle Pleistocene to the *** demonstrate that anhysteretic remanent magnetization(arm),a measure of magnetic mineral content in sediment,provides a good proxy of hydrological changes around Lake Biwa since the last glacial *** low-field magnetic susceptibility is most widely used for stratigraphic correlation of core samples and detection of paleoenvironmental changes,arm is more sensitive to concentration of ferrimagnetic minerals such as small magnetite *** previous study on a piston-core recovered in 1995 revealed that the arm increases in the postglacial interval and that the variation in the lower part is likely linked to millennial-scale climate changes during the last glacial *** finding was confirmed by analysis of new piston-cores recovered from other sites in *** arm records reproducibly extend back to 46 ka,featuring major interstadials of Dansgaard-Oeschger cycles and Heinrich *** arm record shows variation similar to total organic carbon(TOC) content,suggesting that flux of finegrained magnetite was increased during the post-glacial and interstadial warm periods as well as flux of wash in nutrients and organic matter.A high-resolution pollen analysis showed that the arm peaks correspond to regional vegetation response with rapid climate changes in the last glacial *** interpret that the increased arm represents enhanced precipitation pro

关键词： Lake Evolution of the East Asian monsoon inferred from environmental magnetic record from Lake Biwa,central Japan arm