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排序方式: 共有525条查询结果,搜索用时 31 毫秒
1.
Zaidatul Akmal Othman Zaida Zakaria Joseph Bagi Suleiman Victor Udo Nna Aminah Che Romli Wan Syaheedah Wan Ghazali Mahaneem Mohamed 《International journal of molecular sciences》2021,22(8)
Obesity and hyperlipidemia are major risk factors for developing vascular diseases. Bee bread (BB) has been reported to exhibit some biological actions, including anti-obesity and anti-hyperlipidemic. This study aims to investigate whether bee bread can ameliorate vascular inflammation and impaired vasorelaxation activity through eNOS/NO/cGMP pathway in obese rats. Forty male Sprague-Dawley rats were randomly divided into four groups (n = 10/group), namely: control (normal group), obese rats (OB group), obese rats treated with bee bread (0.5 g/kg/day, OB/BB group) and obese rats treated with orlistat (10 mg/kg/day, OB/OR group). The latter three groups were given a high-fat diet (HFD) for 6 weeks to induced obesity before being administered with their respective treatments for another 6 weeks. After 12 weeks of the total experimental period, rats in the OB group demonstrated significantly higher Lee obesity index, lipid profile (total cholesterol, triglyceride, low-density lipoprotein), aortic proinflammatory markers (tumor necrosis factor-α, nuclear factor-κβ), aortic structural damage and impairment in vasorelaxation response to acetylcholine (ACh). Bee bread significantly ameliorated the obesity-induced vascular damage manifested by improvements in the lipid profile, aortic inflammatory markers, and the impaired vasorelaxation activity by significantly enhancing nitric oxide release, promoting endothelial nitric oxide synthase (eNOS) and cyclic guanosine monophosphate (cGMP) immunoexpression. These findings suggest that the administration of bee bread ameliorates the impaired vasorelaxation response to ACh by improving eNOS/NO/cGMP-signaling pathway in obese rats, suggesting its vascular therapeutic role. 相似文献
2.
Syafikah Huda Paiman Mukhlis A Rahman Khairul Hamimah Abas Azian Abd Aziz Ahmad Fauzi Ismail Mohd Hafiz Dzarfan Othman Juhana Jaafar Mohammad Noorul Anam Mohd Norddin 《化学工程与技术》2019,42(6):1321-1329
Removal by absorptive ceramic membranes can simultaneously absorb and separate metal ions from water. Alumina/yttria‐stabilized zirconia (Al2O3/YSZ) hollow‐fiber membranes, fabricated using phase inversion and sintering process, were deposited with iron oxide by an in‐situ hydrothermal process. The results showed that α‐Fe2O3 was produced and incorporated across the membranes. A reduction in flux was recorded with the deposition of α‐Fe2O3. However, it improved the adsorption capacity for heavy metal adsorption. The adsorption‐separation test demonstrated that the optimized membrane is able to completely remove Pb(II) ions after two hours. 相似文献
3.
In Malaysia, no long-term daylight data are measured. It was only recently that the need to measure the availability of daylight became urgent when the importance of daylighting in buildings was rediscovered. The hourly daylight availability has been simulated for the Malaysian sky using daylight modelling techniques based on empirical and measured solar irradiation and cloud cover data. This paper presents the techniques involved in producing exterior illuminance data. These data were then compared with measured illuminance at Shah Alam and Bangi, Malaysia. The global illuminance levels are generally high, with values exceeding 80,000 lux at noon during the months when solar irradiation is highest. Even during the months when the ground receives less solar irradiation, the peak illuminance can reach 60,000 lux. Applications and uses of such data are in daylighting design, both for visual and thermal comfort, task illuminance and energy-conscious design of buildings. Recommendations are made at the end of the paper on the various climatic data that are required to be measured for overall daylighting design applications. 相似文献
4.
This work is an experimental study of mechanisms for transition to turbulence in the boundary layer on a rotating disk. In
one case, the focus was on a triad resonance between pairs of traveling cross-flow modes and a stationary cross-flow mode.
The other was on the temporal growth of traveling modes through a linear absolute instability mechanism first discovered by
Lingwood (1995, J Fluid Mech 314:373–405). Both research directions made use of methods for introducing controlled initial
disturbances. One used a distributed array of ink dots placed on the disk surface to enhance a narrow band of azimuthal and
radial wave numbers of both stationary and traveling modes. The size of the dots was small so that the disturbances they produce
were linear. Another approach introduced temporal disturbances by a short-duration air pulse from a hypodermic tube located
above the disk and outside the boundary layer. Hot-wire sensors primarily sensitive to the azimuthal velocity component, were
positioned at different spatial (r,θ) locations on the disk to document the growth of disturbances. Spatial correlation measurements were used with two simultaneous
sensors to obtain wavenumber vectors. Cross-bicoherence was used to identify three-frequency phase locking. Ensemble averages
conditioned on the air pulses revealed wave packets that evolved in time and space. The space–time evolution of the leading
and trailing edges of the wave packets were followed past the critical radius for the absolute instability, r
c
A
. With documented linear amplitudes, the spreading of the disturbance wave packets did not continue to grow in time as r
c
A
was approached. Rather, the spreading of the trailing edge of the wave packet decelerated and asymptotically approached a
constant. This result supports the linear DNS simulations of Davies and Carpenter (2003, J Fluid Mech 486:287–329) who concluded
that the absolute instability mechanism does not result in a global mode, and that linear-disturbance wave packets are dominated
by the convective instability. In contrast, wave-number matching between traveling cross-flow modes confirmed a triad resonance
that lead to the growth of a low azimuthal number (n = 4) stationary mode. At transition, this mode had the largest amplitude. Signs of this mechanism can be found in past flow
visualization of transition to turbulence in rotating disk flows. 相似文献
5.
This paper presents a preliminary study for the removal of COD and suspended solids in wastewater treatment by combining magnetic field and electrocoagulation (EC) technology. The experiments were carried out using batch apparatus and setup in the static method. Batch experiments with two monopolar iron (Fe) plate anodes and cathodes were employed as electrodes. Wastewater samples were prepared from milk powder with an initial COD of 1,140 mgL(-1) and suspended solids of 1,400 mgL(-1) and acidic conditions were employed (pH approximately 3). DC current was varied from 0.5-0.8 A and operating times were between 30 and 50 min. The results show that the effluent wastewater was very clear (turbidity approximately 9 NTU) and its quality exceeded the direct discharge standard. The suspended solids and COD removal efficiencies were as high as 30.6 and 75.5%, respectively. In addition, the experimental results also show that the electrocoagulation could neutralise the pH of wastewater. 相似文献
6.
Hassan Barjini Mohamed Othman Hamidah Ibrahim Nur Izura Udzir 《Peer-to-Peer Networking and Applications》2012,5(1):1-13
Peer-to-Peer networks attracted a significant amount of interest because of their capacity for resource sharing and content
distribution. Content distribution applications allow personal computers to function in a coordinated manner as a distributed
storage medium by contributing, searching, and obtaining digital content. Searching in unstructured P2P networks is an important
problem, which has received considerable research attention. Acceptable searching techniques must provide large coverage rate,
low traffic load, and optimum latency. This paper reviews flooding-based search techniques in unstructured P2P networks. It
then analytically compares their coverage rate, and traffic overloads. Our simulation experiments have validated analytical
results. 相似文献
7.
Izzuddin Tarmizi Ahmad Safri Norlaili Mat Othman Mohd Afzan 《Neural computing & applications》2021,33(11):6233-6246
Neural Computing and Applications - This paper introduces the use of the one-dimensional convolutional neural network (1D-CNN) for end-to-end EEG decoding with application towards a BCI system with... 相似文献
8.
Abouelnaga Amal M. Meaz Talaat M. Othman Abdelmageed M. Ghazy Riyad A. El Nahrawy Amany M. 《SILICON》2021,13(3):623-631
Silicon - The nature of the opening silicate- based surface affects the chemical interaction, spectroscopic and antimicrobial efficiency. The aim of this approach was to evaluate the spectroscopic... 相似文献
9.
El Nahrawy Amany M. Hemdan Bahaa A. Abou Hammad Ali B. Othman Abdelmageed M. Abouelnaga Amal M. Mansour A. M. 《SILICON》2021,13(9):2979-2991
Silicon - Magnesium calcium silicate nanostructures (MCSNS) loaded with (0.0, 0.6, 0.9, and 1.2 wt%) of Cephradine-drug consisting of mesoporous particles were functionally prepared by sol-gel... 相似文献
10.
Synthesis and Characterization of Nano-Composite Alumina–Titania Ceramic Membrane for Gas Separation
A ceramic composite membrane was prepared using a commercial titania ceramic membrane coated by alumina oxide via a sol–gel technique where polyvinyl alcohol (PVA) was used as a binder. The characteristic of the membrane was analyzed in terms of the effect of PVA concentration and sintering temperature on viscosity, pore size, density, porosity and surface area of the membrane. Two vol% of PVA solution containing 4 g of PVA in 100 mL of water was adequate to achieve an appropriate porosity level to avoid cracks on the gel layer. Sol viscosity and pore size of the membrane essentially increased when the PVA concentration was increased. The density of the membrane increased as the sintering temperature increased. The porosity level however, decreased when the temperature was increased. The composite membrane was further characterized in terms of permeability of pure gas at low-temperature region (301 K) where an experimental platform has been developed to perform the permeability studies. 相似文献