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排序方式： 共有301条查询结果，搜索用时 31 毫秒
91.
92.
Rachid Benbouta Abdelkader Mihi Mourad Brioua Salah Madani Lahbib Adami 《physica status solidi (a)》2005,202(13):2462-2466
The problem of a dislocation parallel and close to two free surfaces of a thin foil made up of two plates of different nature, using anisotropic elasticity, is treated numerically. Different applications are presented for the thin homogeneous crystals Al/Al and Cu/Cu and also for the thin bicrystal Al/Cu. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
93.
94.
We consider convection in a uniform fluid-saturated porous layer which is bounded by conducting plates and heated from below.
The primary aim is to determine the identity of the postcritical convection planform as a function of the thicknesses and
conductivities of the bounding plates relative to that of the porous layer. This work complements and extends an early paper
by Riahi (J Fluid Mech 129:153–171, 1983) who considered a situation where the porous layer is bounded by infinitely thick conducting media. We present regions in
parameter space wherein convection in the form of rolls is unstable and within which cells with square planform form the preferred
pattern. 相似文献
95.
96.
We present a numerical study of large deformations of non-linearly elastic membranes. We consider the non-linear membrane model obtained by Le Dret and Raoult using Γ-convergence, in the case of a Saint Venant-Kirchhoff bulk material. We consider conforming P1 and Q1 finite element approximations of the membrane problem and use a non-linear conjugate gradient algorithm to minimize the discrete energy. We present numerical tests including membranes subjected to live pressure loads. 相似文献
97.
98.
Zhiyu Liao Maria Giovanna Lizio Christopher Corden Hazem Khout Emad Rakha Ioan Notingher 《Journal of Raman spectroscopy : JRS》2020,51(10):1986-1995
Intraoperative assessment of surgical margins remains one of the main challenges in cancer surgery. Raman spectroscopy can detect cancer cells with high accuracy, but it is time-consuming. In this paper, we investigated a selective-sampling Raman spectroscopy approach, based on high wavenumber (HW) Raman imaging (spectral range 2,500–3,500 cm−1) and fingerprint Raman spectroscopy (spectral range 600–1,800 cm−1), to reduce the overall tissue analysis time while maintaining high diagnostic accuracy. HW Raman mapping was used as a first step to identify the adipose tissue regions based on the C–H stretching bands at 2,700–2,950 cm−1. As residual tumors are typically found in nonadipose tissue, an algorithm was developed to allocate sampling points for fingerprint Raman spectroscopy at locations corresponding to low intensity in the HW-Raman maps. Preliminary results show that HW-Raman imaging based on a 671 nm laser is effective and fast for mapping of adipose tissue in breast resections, with typical imaging times of 2 min for tissue areas as large as 2 × 2 cm2 areas. Albeit the remaining high fluorescence background in the fingerprint region prevents the use of single 671-nm laser, the HW Raman imaging can be still exploited in combination with 785-nm excitation Raman spectroscopy for identifying residual tumor. Although this study demonstrates the feasibility of this approach, further improvements, such as using single element detectors for HW Raman imaging, are required to increase the analysis speed further towards intraoperative use in the routine clinical setting. 相似文献
99.
Amany Belal Mohamed A. Elanany Eman Y. Santali Ahmed A. Al-Karmalawy Moustafa O. Aboelez Ali H. Amin Magda H. Abdellattif Ahmed B. M. Mehany Hazem Elkady 《Molecules (Basel, Switzerland)》2022,27(11)
Keratoconus (KC) is a serious disease that can affect people of any race or nationality, although the exact etiology and pathogenic mechanism are still unknown. In this study, thirty-two FDA-approved ophthalmic drugs were exposed to virtual screening using docking studies against both the MMP-2 and MMP-9 proteins to find the most promising inhibitors as a proposed computational mechanism to treat keratoconus. Matrix metalloproteinases (MMPs) are zinc-dependent proteases, and MMP inhibitors (MMPIs) are usually designed to interact with zinc ion in the catalytic (CAT) domain, thus interfering with enzymatic activity. In our research work, the FDA-approved ophthalmic medications will be investigated as MMPIs, to explore if they can be repurposed for KC treatment. The obtained findings of the docking study suggest that atenolol and ampicillin are able to accommodate into the active sites of MMP-2 and MMP-9. Additionally, both exhibited binding modes similar to inhibitors used as references, with an ability to bind to the zinc of the CAT. Molecular dynamic simulations and the MM-GBSA binding free-energy calculations revealed their stable binding over the course of 50 ns. An additional pharmacophoric study was carried out on MMP-9 (PDB ID: 1GKC) using the co-crystallized ligand as a reference for the future design and screening of the MMP-9 inhibitors. These promising results open the door to further biological research to confirm such theoretical results. 相似文献
100.
Mohamed F. M. Abdelkader Mohamed H. Mahmoud Lo&#x;ay A. A. Mohamed A. Abdein Khaled Metwally Shinya Ikeno Samar M. A. Doklega 《Molecules (Basel, Switzerland)》2022,27(12)
In the present study, an experiment was carried out on the postharvest of cucumber fruit during a 14-day shelf life. The aim was to assess the impact of calcium nanoparticles (CaNPs) blended with different concentrations of salicylic acid (SA) on the shelf life of cucumbers during the seasons of 2018 and 2019. The investigation further monitored the influences of CaNPs-SA on some physical properties of cucumber, including the percentage weight loss, color, and fruit firmness. In addition, chemical properties, such as total soluble solids (SSC%), total acidity (TA%), total soluble sugars, and chlorophyll pigmentation of the fruit skin, were assessed during a 14-day shelf lifeCell wall degradation enzymes (CWEAs) such as polygalacturonase (PG), cel-lulase (CEL), xylanase (XYL), and pectinase (PT) were also researched. In addition, the generation rates of H2O2 and O2•− were calculated, as well as the reduction of DPPH. The lipid peroxidation (malondialdehyde, MDA) and cell membrane permeability (IL%) of cell wall composites were also determined. CaNPs-SA at 2 mM suppressed CWEAs, preserved fruit quality, reduced weight loss throughout the shelf-life period, and reduced the percent leakage value. At this concentration, we also found the lowest levels of MDA and the highest levels of DPPH. 相似文献