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1.
miR-149 is an miRNA with essential roles in carcinogenesis. This miRNA is encoded by the MIR149 gene on 2q37.3. The miR-149 hairpin produces miR-149-5p and miR-149-3p, which are the “guide” and the sister “passenger” strands, respectively. Deep sequencing experiments have shown higher prevalence of miR-149-5p compared with miR-149-3p. Notably, both oncogenic and tumor suppressive roles have been reported for miR-149-5p. In this review, we summarize the impact of miR-149-5p in the tumorigenesis and elaborate mechanisms of its involvement in this process in a variety of neoplastic conditions based on three lines of evidence, i.e., in vitro, in vivo and clinical settings.  相似文献   
2.
Adaptive beamformers are designed with the aim of detection of noise and intentional destructive interference and then removing them from the desired signal. This is done by placing high attenuation in the direction of the destructive signal in the radiation pattern of antenna arrays without attenuating the signal from a known direction. Minimum variance distortionless response and linearly constrained minimum variance are among such algorithms in mobile communications. A short explanation of the theory and weights formulae of these beamformers will be given. Two designs for weights calculations in Simulink with the added library of DSP-Builder tool from Altera will be presented. Quadrature Rectangular decomposition with Modified Gram-Schmidt algorithm is used instead of the direct matrix inversion. All calculations are done in single floating point mode for the required high accuracy. Modelsim has been used for hardware simulation and measuring the required clock cycles. The target FPGA is Aria10 from Altera which has floating point DSP blocks for high-performance computations. Hardware resources usage, power consumption, maximum clock frequency and update rate for different matrix sizes of these two beamformers are compared and discussed. The results are also compared with some other relevant reported works.  相似文献   
3.
Electrochemical oxidation of some catecholamines such as dopamine (1), l-dopa (2) and methyldopa (3) has been studied in the presence of 4-aminobenzoic acid (4). Some electrochemical techniques such as cyclic voltammetry using diagnostic criteria derived by Nicholson and Shain for various electrode mechanisms and controlled-potential coulometry were used. Variation in cathodic peaks due to the competition between intramolecular and intermolecular Michael addition reaction was studied in various pH values, and the best conditions for reaction with 4-aminobenzoic acid was obtained. The results indicate an ECE mechanism. The observed homogeneous rate constant (kobs) for Michael addition reaction was estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results. Also, the Michael addition reaction rate constants (km) were calculated using microscopic acidic dissociation constant of ammonium groups in 4-aminobenzoic acid. The chemical oxidation reaction of catecholamines with periodate in the presence of 4-aminobenzoic acid was also studied spectrophotometrically.  相似文献   
4.
The air and water stable room temperature ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [BMP]Tf2N, multi-walled carbon nanotubes (MWCNTs), graphite powder and also a new synthesized Schiff base have been used to fabricate a new carbon composite electrode with very attractive sensing behavior. The new Schiff base was synthesized to apply as a selective agent in electrochemical responses of the voltammetric sensor for the determination of mercury (II) ions in aqueous solutions. The proposed sensor allowed the determination of mercury (II) in the wide linear dynamic range of 0.2–260.0 nmol l?1. The limit of detection (LOD) was noticed to be 0.05 nmol l?1. The prepared electrode was used for mercury (II) determination in the real samples.  相似文献   
5.
The study of moisture migration in a layered structure made of distinct building materials is of great importance for the understanding of its hygrothermomechanical response and for the design consideration of long-term structural integrity and durability. Modeling of moisture migration in an fiber reinforced polymer (FRP) composite upgraded masonry structure is particularly necessary, since the interfacial adhesive between the reinforcing FRP laminate and the host masonry can be susceptible to moisture damages. In this study, a generic theoretical formulation based on the framework of the Fourier moisture diffusion model was developed for a layered structure. The resulting governing equation was expressed in terms of humidity potential state variable whose relation with the moisture content state variable of the constituent material was defined in the sorption isotherm material property. Finite element implementation of the humidity potential formulation was also carried out. The finite element humidity migration modeling scheme was then utilized to perform two case studies. It was shown that the moisture migration processes in a concrete slab with a reinforcing FRP laminate partially covering one surface as well as in an FRP reinforced URM unit with air cavity can be captured in details when these structures are subjected to outdoor/indoor isothermal humidity gradients.  相似文献   
6.
A method was proposed for the preconcentration of some transition elements at trace levels using a column packed with silica gel modified by a synthetic ligand. Metal ions were adsorbed on 2,4,6-trimorpholino-1,3,5-triazin modified silica gel, then analytes retained on the adsorbent were eluted by 1 mol L−1 hydrochloric acid and determined by flame atomic absorption spectrometry (FAAS). The influences of some experimental parameters including pH of the sample solution, weight of adsorbent, type, concentration and volume of eluent, flow rates of the sample solution and eluent, and sample volume on the preconcentration efficiency have been investigated. The influences of some matrix elements were also examined. The method also was used for simultaneous preconcentration of these elements and the method was successfully applied to the preconcentration and determination of them. The detection limits of the method for Ni2+, Co2+, Cd2+ and Zn2+were 0.29, 0.20, 0.23 and, 0.30 ng mL−1, respectively. The application of this modified silica gel to preconcentration of investigated cation from tap water, lake water, urine and apple leaves gave high accuracy and precision (relative standard deviation (R.S.D.) <3%).  相似文献   
7.
A cloud-point extraction process using micelle of the cationic surfactant CTAB to extract Mo(VI) from aqueous solutions was investigated. The method is based on the color reaction of molybdenum with bromopyrogallol red in the presence of potassium iodide at pH 1.0 glycine/HCl buffer media and micelle-mediated extraction of complex. The optimal extraction and reaction conditions (e.g., surfactant concentration, reagent concentration and effect of time) were studied and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration and improvement factors) were obtained. Linearity was obeyed in the range of 0.3-320.0 ng mL(-1) of molybdenum(VI) ion and the detection limit of the method was 0.1 ng mL(-1). The relative standard deviation (R.S.D.) and relative error for five replicate measurements of 65.0 ng mL(-1) Mo(VI) were 1.1% and 1.9%, respectively. The interference effect of some anions and cations was also tested. The method was applied to the determination of molybdenum(VI) in steels and tap water and well water samples.  相似文献   
8.
Effect of loading of C-cloth with ethylenediaminetetraacetic acid (EDTA) on the adsorption capacity for the adsorption of several metal cations was studied. The concentration of ions in the solution was monitored using atomic absorption spectrometry. The adsorption isotherm data for the cations were derived at 25 degrees C and treated according to Langmuir and Freundlich models and was found that for most of the investigated cations Langmuir model was more successful. Adsorption capacities determined from Langmuir isotherms. Loading of the adsorbent with EDTA increased the adsorption capacity for the adsorption of all of the investigation ions.  相似文献   
9.
The incidence of various types of cancer is increasing globally. To reduce the critical side effects of cancer chemotherapy, naturally derived compounds have been considered for cancer treatment. Gymnosperms are a group of plants found worldwide that have traditionally been used for therapeutic applications. Paclitaxel is a commercially available anticancer drug derived from gymnosperms. Other natural compounds with anticancer activities, such as pinostrobin and pinocembrin, are extracted from pine heartwood, and pycnogenol and enzogenol from pine bark. Gymnosperms have great potential for further study for the discovery of new anticancer compounds. This review aims to provide a rational understanding and the latest developments in potential anticancer compounds derived from gymnosperms.  相似文献   
10.
Viral-associated respiratory infectious diseases are one of the most prominent subsets of respiratory failures, known as viral respiratory infections (VRI). VRIs are proceeded by an infection caused by viruses infecting the respiratory system. For the past 100 years, viral associated respiratory epidemics have been the most common cause of infectious disease worldwide. Due to several drawbacks of the current anti-viral treatments, such as drug resistance generation and non-targeting of viral proteins, the development of novel nanotherapeutic or nano-vaccine strategies can be considered essential. Due to their specific physical and biological properties, nanoparticles hold promising opportunities for both anti-viral treatments and vaccines against viral infections. Besides the specific physiological properties of the respiratory system, there is a significant demand for utilizing nano-designs in the production of vaccines or antiviral agents for airway-localized administration. SARS-CoV-2, as an immediate example of respiratory viruses, is an enveloped, positive-sense, single-stranded RNA virus belonging to the coronaviridae family. COVID-19 can lead to acute respiratory distress syndrome, similarly to other members of the coronaviridae. Hence, reviewing the current and past emerging nanotechnology-based medications on similar respiratory viral diseases can identify pathways towards generating novel SARS-CoV-2 nanotherapeutics and/or nano-vaccines.  相似文献   
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