1,919 research outputs found

    Orbital hemangiopericytoma in an Asian population

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    Background/PurposeHemangiopericytoma is a very rare orbital tumor. The purpose of this study was to report the clinical and histopathological features of six cases of orbital hemangiopericytoma in an Asian population.MethodsClinical and histopathological features were reviewed in six patients who were histopathologically confirmed as having primary orbital hemangiopericytoma in National Taiwan University Hospital between May 2001 and December 2010.ResultsAmong the six cases who were diagnosed as having primary orbital hemangiopericytoma, all lesions were reported as vascular tumors and featured branching “staghorn appearance” vessels. All patients, including one male and five females, presented with progressive proptosis and some associated symptoms such as extraocular motility limitation with diplopia, displacement of the globe, afferent pupillary defect, congested vessels of conjunctiva, or decreased visual acuity. On computed tomography, the orbital tumors tended to manifest as circumscribed masses with homogeneous medium-to-high enhancement with contrast studies. All six patients received surgical treatments, and four of them had additional radiotherapy. Three patients had recurrence after surgeries, and one of them had multiple metastases to lung and liver. All patients were still alive after a follow-up period of 5–10 years.ConclusionOrbital hemangiopericytoma has malignant potential, which may lead to local recurrence and/or metastasis. Histopathological findings alone are insufficient to predict the behavior of this tumor. Therefore, both clinical and histopathological findings are important to evaluate the treatment outcomes. Total excision accompanied with radiotherapy is suggested and long-term follow-up is required

    Poly[[μ-1,4-bis­(4,5-dihydro-1,3-oxazol-2-yl)benzene-κ2 N:N′]di-μ-bromido-cadmium]

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    In the title coordination polymer, [CdBr2(C12H12N2O2)]n, the CdII ion, situated on an inversion centre, is coordinated by four bridging Br atoms and two N atoms from two 1,4-bis­(4,5-dihydro-1,3-oxazol-2-yl)benzene (L) ligands in a distorted octa­hedral geometry. The L ligand, which also lies across an inversion centre, bridges two CdII ions, forming layers parallel to (010)

    Structural and Thermodynamic Factors of Suppressed Interdiffusion Kinetics in Multi-component High-entropy Materials

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    We report multi-component high-entropy materials as extraordinarily robust diffusion barriers and clarify the highly suppressed interdiffusion kinetics in the multi-component materials from structural and thermodynamic perspectives. The failures of six alloy barriers with different numbers of elements, from unitary Ti to senary TiTaCrZrAlRu, against the interdiffusion of Cu and Si were characterized, and experimental results indicated that, with more elements incorporated, the failure temperature of the barriers increased from 550 to 900°C. The activation energy of Cu diffusion through the alloy barriers was determined to increase from 110 to 163 kJ/mole. Mechanistic analyses suggest that, structurally, severe lattice distortion strains and a high packing density caused by different atom sizes, and, thermodynamically, a strengthened cohesion provide a total increase of 55 kJ/mole in the activation energy of substitutional Cu diffusion, and are believed to be the dominant factors of suppressed interdiffusion kinetics through the multi-component barrier materials

    Folding Mechanism Revealing of PGB1 by FRET and Molecular Simulation

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    Dynamic Finite Element Analysis on Underlay Microstructure of Cu/low-k Wafer during Wirebonding

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    The aim of present research is to investigate dynamic stress analysis for microstructure of Cu/Low-K wafer subjected to wirebonding predicted by finite element software ANSYS/LS-DYNA. Two major analyses are conducted in the present research. In the first, the characteristic of heat affected zone (HAZ) and free air ball (FAB) on ultra thin Au wire have been carefully experimental measured. Secondary, the dynamic response on Al pad/beneath the pad of Cu/low-K wafer during wirebonding process has been successfully predicted by finite element analysis (FEA). Tensile mechanical properties of ultra thin wire before/after electric flame-off (EFO) process have been investigated by self-design pull test fixture. The experimental obtained hardening value has significantly influence on localize stressed area on Al pad. This would result in Al pad squeezing around the smashed FAB during impact stage and the consequent thermosonic vibration stage. Microstructure of FAB and HAZ are also carefully measured by micro/nano indentation instruments. All the measured data serves as material inputs for the FEA explicit software ANSYS/LS-DYNA. Because the crack of low-k layer and delamination of copper via are observed, dynamic transient analysis is performed to inspect the overall stress/strain distributions on the microstructure of Cu/low-k wafer. Special emphasizes are focused on the copper via layout and optimal design of Cu/low-k microstructure. It is also shown that the Al pad can be replaced by Al-Cu alloy pad or Cu pad to avoid large deformation on pad and cracking beneath the surface. A series of comprehensive experimental works and FEA predictions have been performed to increase bondability and reliability in this study

    Domain-Generalized Face Anti-Spoofing with Unknown Attacks

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    Although face anti-spoofing (FAS) methods have achieved remarkable performance on specific domains or attack types, few studies have focused on the simultaneous presence of domain changes and unknown attacks, which is closer to real application scenarios. To handle domain-generalized unknown attacks, we introduce a new method, DGUA-FAS, which consists of a Transformer-based feature extractor and a synthetic unknown attack sample generator (SUASG). The SUASG network simulates unknown attack samples to assist the training of the feature extractor. Experimental results show that our method achieves superior performance on domain generalization FAS with known or unknown attacks.Comment: IEEE International Conference on Image Processing (ICIP 2023

    Matrix metalloproteinase-3 promoter polymorphisms but not dupA-H. pylori correlate to duodenal ulcers in H. pylori-infected females

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    <p>Abstract</p> <p>Background</p> <p>This study investigated if the <it>H. pylori dupA </it>genotype and certain host single nucleotide polymorphisms (SNPs) of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs), including MMP-3, MMP-7, MMP-9, TIMP-1 and TIMP-2, might correlate with ulcer risk of <it>H. pylori-</it>infected Taiwanese patients.</p> <p>Results</p> <p>Of the 549 <it>H. pylori-</it>infected patients enrolled, 470 patients (265 with gastritis, 118 with duodenal ulcer, and 87 with gastric ulcer) received SNPs analysis of MMP-3<sub>-1612 6A > 5A</sub>, MMP-7<sub>-181 A > G</sub>, MMP-9<sub>exon 6 A > G</sub>, TIMP-1<sub>372 T > C </sub>and TIMP-2<sub>-418 G > C </sub>by PCR-RFLP. The 181 collected <it>H. pylori </it>isolates were detected for the <it>dupA </it>genotype by PCR. The rates of <it>dupA</it>-positive <it>H. pylori </it>infection were similar among patients with duodenal ulcer (22.8%), gastric ulcer (20.0%), and gastritis (25.5%) (<it>p </it>> 0.05). Males had higher rates of duodenal ulcer and gastric ulcer than females (<it>p </it>< 0.01). Of <it>H. pylori</it>-infected patients, the MMP-3 6A6A genotype were more common in patients with duodenal ulcers than in those with gastritis (87.7% <it>vs</it>. 74.9%, <it>p </it>< 0.05) in females. This genotype had a 2.4-fold (95% CI: 1.02-5.66) increased risk of duodenal ulcer, compared to those with the 5A carrier. Combining the MMP-3/TIMP-1 genotype as 6A6A/CC, the risk of duodenal ulcer increased up to 3.6 fold (<it>p </it>< 0.05) in <it>H. pylori-</it>infected females.</p> <p>Conclusions</p> <p>The MMP-3 promoter polymorphism, but not the <it>dupA</it>-status, may correlate with susceptibility to duodenal ulcer after <it>H. pylori </it>infection in Taiwanese females.</p
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