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21.
Mohd Saberi Mohamad Sigeru Omatu Safaai Deris Michifumi Yoshioka 《Artificial Life and Robotics》2009,14(1):12-15
Microarray data are expected to be useful for cancer classification. However, the process of gene selection for the classification
contains a major problem due to properties of the data such as the small number of samples compared with the huge number of
genes (higher-dimensional data), irrelevant genes, and noisy data. Hence, this article aims to select a near-optimal (small)
subset of informative genes that is most relevant for the cancer classification. To achieve this aim, an iterative approach
based on genetic algorithms has been proposed. Experimental results show that the performance of the proposed approach is
superior to other previous related work, as well as to four methods tried in this work. In addition, a list of informative
genes in the best gene subsets is also presented for biological usage. 相似文献
22.
Hybrid Paper–Plastic Microchip for Flexible and High‐Performance Point‐of‐Care Diagnostics 下载免费PDF全文
Mohamed Shehata Draz Maryam Moazeni Manasa Venkataramani Harini Lakshminarayanan Ecem Saygili Nivethitha Kota Lakshminaraasimulu Kamyar Mehrabi Kochehbyoki Manoj Kumar Kanakasabapathy Shirin Shabahang Anish Vasan Mohamad Ali Bijarchi Adnan Memic Hadi Shafiee 《Advanced functional materials》2018,28(26)
A low‐cost and easy‐to‐fabricate microchip remains a key challenge for the development of true point‐of‐care (POC) diagnostics. Cellulose paper and plastic are thin, light, flexible, and abundant raw materials, which make them excellent substrates for mass production of POC devices. Herein, a hybrid paper–plastic microchip (PPMC) is developed, which can be used for both single and multiplexed detection of different targets, providing flexibility in the design and fabrication of the microchip. The developed PPMC with printed electronics is evaluated for sensitive and reliable detection of a broad range of targets, such as liver and colon cancer protein biomarkers, intact Zika virus, and human papillomavirus nucleic acid amplicons. The presented approach allows a highly specific detection of the tested targets with detection limits as low as 102 ng mL?1 for protein biomarkers, 103 particle per milliliter for virus particles, and 102 copies per microliter for a target nucleic acid. This approach can potentially be considered for the development of inexpensive and stable POC microchip diagnostics and is suitable for the detection of a wide range of microbial infections and cancer biomarkers. 相似文献
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24.
Yasin Orooji Hessamaddin Sohrabi Nima Hemmat Fatemeh Oroojalian Behzad Baradaran Ahad Mokhtarzadeh Mohamad Mohaghegh Hassan Karimi‑Maleh 《纳微快报(英文)》2021,(1):337-366
A novel coronavirus of zoonotic origin(SARSCoV-2)has recently been recognized in patients with acute respiratory disease.COVID-19 causative agent is structurally and genetically similar to SARS and bat SARS-like coronaviruses.The drastic increase in the number of coronavirus and its genome sequence have given us an unprecedented opportunity to perform bioinformatics and genomics analysis on this class of viruses.Clinical tests like PCR and ELISA for rapid detection of this virus are urgently needed for early identification of infected patients.However,these techniques are expensive and not readily available for point-of-care(POC)applications.Currently,lack of any rapid,available,and reliable POC detection method gives rise to the progression of COVID-19 as a horrible global problem.To solve the negative features of clinical investigation,we provide a brief introduction of the general features of coronaviruses and describe various amplification assays,sensing,biosensing,immunosensing,and aptasensing for the determination of various groups of coronaviruses applied as a template for the detection of SARS-CoV-2.All sensing and biosensing techniques developed for the determination of various classes of coronaviruses are useful to recognize the newly immerged coronavirus,i.e.,SARS-CoV-2.Also,the introduction of sensing and biosensing methods sheds light on the way of designing a proper screening system to detect the virus at the early stage of infection to tranquilize the speed and vastity of spreading.Among other approaches investigated among molecular approaches and PCR or recognition of viral diseases,LAMP-based methods and LFAs are of great importance for their numerous benefits,which can be helpful to design a universal platform for detection of future emerging pathogenic viruses. 相似文献
25.
Mohamad Rusop Tetsuo Soga Takashi Jimbo 《Solar Energy Materials & Solar Cells》2006,90(18-19):3214-3222
The phosphorus-doped amorphous carbon (n-C:P) films were grown by r.f. power-assisted plasma-enhanced chemical vapor deposition at room temperature using solid phosphorus target. The influence of phosphorus doping on material properties of n-C:P based on the results of simultaneous characterization are reported. Moreover, the solar cell properties such as series resistance, short circuit current density (Jsc), open circuit current voltage (Voc), fill factor (FF) and conversion efficiency (η) along with the spectral response are reported for the fabricated carbon based n-C:P/p-Si heterojunction solar cell were measured by standard measurement technique. The cells performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm2, 25 °C). The maximum of Voc and Jsc for the cells are observed to be approximately 236 V and 7.34 mA/cm2, respectively for the n-C:P/p-Si cell grown at lower r.f. power of 100 W. The highest η and FF were found to be approximately 0.84% and 49%, respectively. We have observed the rectifying nature of the heterojunction structures is due to the nature of n-C:P films. 相似文献
26.
Fard Behnam Miripour Mosadeghzad Mohamad 《International Journal of Control, Automation and Systems》2019,17(9):2343-2353
International Journal of Control, Automation and Systems - In this paper, a novel manipulability based three-level hierarchical approach is suggested for control of perturbed bipedal walking. An... 相似文献
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28.
Sakizadeh Mohamad Mohamed Mohamed M. A. Klammler Harald 《Water Resources Management》2019,33(4):1425-1437
Water Resources Management - Overexploitation of groundwater in the Malayer Plain has resulted in a continuous decline of groundwater levels over recent years with associated risks to water... 相似文献
29.
Mohammed M. Mehanna Mohamad Ibrahim Shabarek Hoda A. Elmartadny 《Drug development and industrial pharmacy》2019,45(3):485-497
Pravastatin is a promising drug utilized in the treatment of hyperlipidemia, yet, its main clinical limitation is due to gastric liability which fractions its oral bioavailability to less than 18%. The purpose of the current study is to encapsulate pravastatin into Eudragit®-based spray-dried microparticles aspiring to overcome its acid liability. With the aim to optimize the microparticles, formulation and process parameters were studied through acid resistance challenging test. Physicochemical characterization of the optimized spray-dried pH-sensitive microparticles namely; in-vitro dissolution, surface morphology, compatibility, and solid-state studies were performed. Moreover, in-vivo evaluation of the microparticles and accelerated stability studies were carried out. The results outlined that polymer to drug ratio at 5:1 and pravastatin concentration at 1%w/w in spray-drying feed solution showed 38.55% and 53.97% encapsulation efficiency, respectively. The significance of process parameters specifically; the flow rate and the inlet temperature on microparticles surface integrity were observed, and optimized until encapsulating efficiency reached 72.37%. The scanning electron microscopical examination of the optimized microparticles illustrate uniform smooth surface spheres entrapping the drug in an amorphous state as proved through Differential Scanning Calorimetry (DSC) and Fourier Transfer Infrared (FTIR) studies. The in-vivo evaluation demonstrated a 5-fold enhancement in pravastatin bioavailability compared to the marketed product. The results provided evidence for the significance of spray-dried pH-sensitive microparticles as a promising carrier for pravastatin, decreasing its acid liability, and improving its bioavailability. 相似文献
30.
Low-density lipoprotein (LDL) is known to be a mitogenic factor for vascular smooth muscle cells (VSMCs), fibroblasts, and endothelial cells. In the current study, we describe possible intracellular mechanisms by which LDL elicits its mitogenic effects. Stimulation of VSMCs with LDL resulted in a pertussis-toxin (PTX)-sensitive stimulation of the 44-kDa mitogen-activated protein (MAP) kinase (p44(mapk)) and 42-kDa MAP kinase (p42(mapk)) isoforms as well as in a PTX-sensitive increase in intracellular free Ca2+ concentration ([Ca2+]i). Binding of the LDL-induced increase in [Ca2+]i to the intracellular Ca2+ chelator bis(2-amino-5-methylphenoxy)ethane-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester resulted in a 2-fold increase in the phosphorylated p44(mapk) and p42(mapk) isoforms but did not influence the LDL effect of VSMC DNA synthesis. PD 98059, a MAP kinase kinase inhibitor, remarkably attenuated the LDL-induced activation of MAP kinases and DNA synthesis. Treatment of normal human skin fibroblasts and human fibroblasts isolated from patients with familial hypercholesterolemia homozygote class 1 mutations, which are not able to produce the classic LDL receptor, resulted also in a PTX-sensitive increase in cell DNA synthesis and stimulation of the p44(mapk) and p42(mapk) isoforms in both cell types. These results demonstrate that the mitogenic effect of LDL is mediated by a PTX-sensitive Gi-coupled receptor that is independent of its classic receptor and involves activation of MAP kinase isoforms. Furthermore, the mitogenic effect of LDL may be mediated by the activation of the MAP kinase pathway. In contrast, the LDL-induced increase in [Ca2+]i may be implicated in this process only in conjugation with other signaling components. 相似文献