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Abdullah Seçgin Ayşe Saide Sarıgül 《International Journal of Mechanics and Materials in Design》2010,6(1):17-25
In this study, sound source localization and identification of a refrigerator were accomplished by using the half-space boundary element method (BEM) based on surface velocity measurements. Surface velocities of the refrigerator were measured by a vibration test set-up; and two main dominant excitation frequencies were determined. The velocity data were fed to half-contact BE model of the refrigerator built in our “in-house” BEM computer code. The code calculated surface acoustic pressure distributions. The surface pressures exposed the location of sound sources of the refrigerator. Near-field sound radiation pattern of the localized sources were obtained by the surface pressure-input to the computer code. 相似文献
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OBJECTIVE: To compare the value of closed percutaneous pleural biopsy versus pleuroscopy for diagnosis of undiagnosed exudative pleural effusion in an age-dependent manner. DESIGN: Prospective clinical study. SETTING: University hospitals. PATIENTS: Forty-nine consecutive patients with undiagnosed exudative pleural effusion following the initial clinical and paraclinical investigations, including bronchoscopy. Cases were divided into younger and older groups according to their ages. INTERVENTION: Closed pleural biopsy immediately followed by pleuroscopy with a flexible fiberoptic bronchoscope from the same incision site. RESULTS: In the older age group, pleuroscopy was superior to closed pleural biopsy for the diagnosis of the underlying pleural disease (P = 0.0007), while they were almost equally diagnostic in the younger cases (P = 0.58). CONCLUSION: For those patients with undiagnosed exudative pleural effusion who are older than 50 years of age, pleuroscopy could be chosen as the first procedure of choice as compared to closed pleural biopsy if malignant pleural effusion is suspected. 相似文献
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A Ayme-Southgate R Southgate J Saide GM Benian ML Pardue 《Canadian Metallurgical Quarterly》1995,128(3):393-403
In Drosophila, the large muscle protein, projectin, has very different localizations in synchronous and asynchronous muscles, suggesting that projectin has different functions in different muscle types. The multiple projectin isoforms are encoded by a single gene; however they differ significantly in size (as detected by gel mobility) and show differences in some peptide fragments, presumably indicating alternative splicing or termination. We now report additional sequence of the projectin gene, showing a kinase domain and flanking regions highly similar to equivalent regions of twitchin, including a possible autoinhibitory region. In spite of apparent differences in function, all isoforms of projectin have the kinase domain and all are capable of autophosphorylation in vitro. The projectin gene is in polytene region 102C/D where the bentD phenotype maps. The recessive lethality of bentD is associated with a breakpoint that removes sequence of the projectin kinase domain. We find that different alleles of the highly mutable recessive lethal complementation group, l(4)2, also have defects in different parts of the projectin sequence, both NH2-terminal and COOH-terminal to the bentD breakpoint. These alleles are therefore renamed as alleles of the bent locus. Adults heterozygous for projectin mutations show little, if any, effect of one defective gene copy, but homozygosity for any of the defects is lethal. The times of death can vary with allele. Some alleles kill the embryos, others are larval lethal. These molecular studies begin to explain why genetic studies suggested that l(4)2 was a complex (or pseudoallelic) locus. 相似文献
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A sol-gel dip coating technique was used to fabricate TiO2/SnO2 nano composite thin films on soda-lime glass. The solutions of SnO2 and TiO2 were mixed with different molar ratios of SnO2:TiO2 as 0, 3, 4, 6, 8, 9, 10.5, 13, 15, 19.5, 25 and 28 mol.% then the films were prepared by dip coating of the glasses. The effects of SnO2 concentration, number of coating cycles and annealing temperature on the hydrophilicity of films were studied using contact angle measurement. The films were characterized by means of scanning electron microscopy, X-ray diffraction and atomic force microscopy measurements. The nano composite thin films fabricated with 8 mol.% of SnO2, four dip coating cycles and annealing temperature of 500 °C showed super-hydrophilicity. 相似文献
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Elnaz Rezaian Mingjun Wei 《International journal for numerical methods in engineering》2020,121(8):1629-1646
Model order reduction approaches, such as proper orthogonal decomposition (POD)-Galerkin projection, provide a systematic manner to construct Reduced-Order Models (ROM) from pregenerated high-fidelity datasets. The current study focuses on the stabilization of ROMs built from high-fidelity simulation data of a supersonic flow passing a circular cylinder, which features strong interactions between shockwaves and vortices. As shown in previous literatures and the current study, an implicit subspace correction (ISC) method is efficient in the stabilization of similar problems, but its accuracy is not consistent when applied on different ROMs; on the other hand, an eigenvalue reassignment (ER) method delivers superb accuracy when the mode number is small, but becomes too expensive and less robust as the number increases. A Hybrid method is proposed here to balance the computational cost while improving the overall robustness/accuracy in ROM stabilization. The Hybrid method first handles the majority of the modes using the ISC method and then applies the ER method to fine tune a smaller number of modes under a constraint for accuracy. Furthermore, when the typical L2 inner product is changed to a symmetry inner product in both POD computation and Galerkin projection, the performance of the stabilized ROMs is substantially improved for all methods. 相似文献
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Here we demonstrated a simple and reliable method to prepare single or multiple core/shell structured capsules and then demonstrate how to produce single or multiple-layer hollow spheres. Those capsules or hollow spheres could be made of organic and/or inorganic functional materials depending on the experimental design. Core–shell composite capsules consisting of TiO2–polyaniline (PANI) shell and polystyrene (PS) core were prepared by using core–shell structured sulfonated-PS spheres as templates. Aniline was polymerized in the shell of sulfonated-PS spheres. Since the PANI was in situ doped by sulfonic acid, the as-synthesized composite capsules had good conductivity. After PS cores were dissolved in solvent, hollow TiO2–PANI spheres formed, which could be further calcined to produce mesoporous hollow TiO2 spheres. The cavity size of the hollow spheres was uniform, at approximately 170 nm in diameter and with a shell thickness of 30 nm. The cavity size and the shell thickness can be synchronously controlled by adjusting the sulfonation reaction time of PS spheres. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray powder scattering were employed to characterize these as-prepared spheres. 相似文献
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Antioxidative activity of lactobacilli measured by oxygen radical absorbance capacity 总被引:1,自引:0,他引:1
The reducing ability and antioxidative activity of some species of Lactobacillus were compared under in vitro conditions. Cultures of Lactobacillus delbrueckii ssp. lactis, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus acidophilus, and Lactobacillus casei were grown at 37 degrees C in de Man, Rogosa, Sharpe (MRS) broth supplemented with 0.5% 2,3,5 triphenyl tetrazolium chloride (TTC) to evaluate reducing activity. Reduced TTC was extracted from the cultures with acetone, and the intensity of the red color measured colorimetrically at 485 nm was an indication of reducing activity. The lactobacilli varied significantly in relative ability to reduce TTC when grown in MRS broth for 15 h. The relative amounts of growth as indicated by pH values at 18 h appeared to influence the amount of reduction. Antioxidative activity was evaluated by the ability of the whole cells or the cell-free extracts from cultures to protect a protein from being attacked by free radicals. These analyses were performed using the oxygen radical absorbance capacity method. All cultures tested exhibited some degree of antioxidative activity. Among the treatments, the cell-free extracts from cells grown in MRS broth exhibited significantly higher values than did whole cells. There was no apparent relationship between the reducing and antioxidative activities of the cultures evaluated. The results from this study show that these cultures can provide a source of dietary antioxidants. Furthermore, selection of cultures that produce antioxidants as starters could provide yet another health or nutritional benefit from cultured or culture-containing dairy products. 相似文献
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BACKGROUND: Treatment of patients with malignant pleural effusions is mostly palliative. Tetracycline and bleomycin are the two most commonly used agents for the treatment of pleurodesis. In this study, the authors used a combination of the two drugs for this particular purpose. METHODS: Sixty patients with massive malignant pleural effusions were divided in 3 equal groups in a simple randomized manner. Tetracycline (20 mg/kg [maximum of 2 g] in 50 mL of normal saline) was administered through a chest tube in Group 1. Group 2 received bleomycin (1 U/kg [maximum of 60 U] in 50 mL of normal saline). Group 3 received the above 2 preparations (tetracycline, 20 mg/kg [maximum of 2 g] in 40 mL of normal saline and bleomycin, 1 U/kg [maximum of 60 U] in 30 mL of normal saline) instilled one after the other, while the chest tube was clamped for 5 minutes in the interim. Follow-up examinations were performed at 7 days, 30 days, 60 days, 90 days, and 6 months. RESULTS: There was no significant difference in the complete response rate of the 3 groups during the first 4 months. At the end of the study, Group 3 had a significantly higher complete response rate (70%) compared with Groups 1 and 2 (35% and 25%, respectively) (P = 0.02). CONCLUSIONS: The response to use of a combination of bleomycin and tetracycline for the treatment of patients with pleurodesis is superior to that achieved by either of these agents used alone. 相似文献