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291.
Lung adenocarcinoma is one of the major causes of mortality. Current methods of diagnosis can be improved through identification of disease specific biomarkers. MicroRNAs are small non‐coding regulators of gene expression, which can be potential biomarkers in various diseases. Thus, the main objective of this study was to gain mechanistic insights into genetic abnormalities occurring in lung adenocarcinoma by implementing an integrative analysis of miRNAs and mRNAs expression profiles in the case of both smokers and non‐smokers. Differential expression was analysed by comparing publicly available lung adenocarcinoma samples with controls. Furthermore, weighted gene co‐expression network analysis is performed which revealed mRNAs and miRNAs significantly correlated with lung adenocarcinoma. Moreover, an integrative analysis resulted in identification of several miRNA–mRNA pairs which were significantly dysregulated in non‐smokers with lung adenocarcinoma. Also two pairs (miR‐133b/Protein Kinase C Zeta (PRKCZ) and miR‐557/STEAP3) were found specifically dysregulated in smokers. Pathway analysis further revealed their role in important signalling pathways including cell cycle. This analysis has not only increased the authors’ understanding about lung adenocarcinoma but also proposed potential biomarkers. However, further wet laboratory studies are required for the validation of these potential biomarkers which can be used to diagnose lung adenocarcinoma.Inspec keywords: cancer, molecular biophysics, patient diagnosis, tumours, RNA, proteins, lung, genetics, medical diagnostic computing, molecular configurationsOther keywords: miRNAs expression profiles, mRNAs expression profiles, smokers, nonsmokers, integrative analysis, lung adenocarcinoma, microRNAs, disease specific biomarkers, noncoding regulators, genetic abnormalities, weighted gene coexpression network analysis  相似文献   
292.
Inspired from the funtioning and responsiveness of biological ion channels, researchers attempt to develop biosensing systems based on polymer and solid-state nanochannels. The applicability of these nanochannels for detection/sensing of any foreign analyte in the surrounding environment depends critically on the surface characteristics of the inner walls. Attaching recognition sites to the channel walls leads to the preparation of sensors targeted at a specific molecule. There are many nanochannel platforms for the detection of DNA and proteins, but only a few are capable of detecting small molecules. Here, we describe a nanochannel platform for the detection of hydrogen peroxide, H(2)O(2), which is not only a toxic waste product in the cellular systems but also a key player in the redox signaling pathways. The sensor is based on single conical nanochannels fabricated in an ion tracked polymer membrane. The inner walls of the channel are decorated with horseradish peroxidase (HRP) enzyme using carbodiimide coupling chemistry. The success of the HRP immobilization on the channel surface is confirmed by measuring the pH-dependent current-voltage (I-V) curves of the system. The reported HRP-nanochannel system detects nanomolar concentrations of H(2)O(2) with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) as the substrate. The immobilized HRP enzyme is thus capable of inducing redox reactions in a subfemtoliter volume of single nanochannels. We demonstrate that functioning of the designed biosensor is reversible and can be used multiple times to detect H(2)O(2) at various concentrations.  相似文献   
293.
294.
Transition‐metal oxide nanoparticles and molecular coordination compounds are highlighted as functional mimics of halogenating enzymes. These enzymes are involved in halometabolite biosynthesis. Their activity is based upon the formation of hypohalous acids from halides and hydrogen peroxide or oxygen, which form bioactive secondary metabolites of microbial origin with strong antibacterial and antifungal activities in follow‐up reactions. Therefore, enzyme mimics and halogenating enzymes may be valuable tools to combat biofilm formation. Here, halogenating enzyme models are briefly described, enzyme mimics are classified according to their catalytic functions, and current knowledge about the settlement chemistry and adhesion of fouling organisms is summarized. Enzyme mimics with the highest potential are showcased. They may find application in antifouling coatings, indoor and outdoor paints, polymer membranes for water desalination, or in aquacultures, but also on surfaces for food packaging, door handles, hand rails, push buttons, keyboards, and other elements made of plastic where biofilms are present. The use of natural compounds, formed in situ with nontoxic and abundant metal oxide enzyme mimics, represents a novel and efficient “green” strategy to emulate and utilize a natural defense system for preventing bacterial colonization and biofilm growth.  相似文献   
295.
Anoxic sulfide biooxidation using nitrite as electron acceptor   总被引:3,自引:0,他引:3  
Biotechnology can be used to assess the well being of ecosystems, transform pollutants into benign substances, generate biodegradable materials from renewable sources, and develop environmentally safe manufacturing and disposal processes. Simultaneous elimination of sulfide and nitrite from synthetic wastewaters was investigated using a bioreactor. A laboratory scale anoxic sulfide-oxidizing (ASO) reactor was operated for 135 days to evaluate the potential for volumetric loading rates, effect of hydraulic retention time (HRT) and substrate concentration on the process performance. The maximal sulfide and nitrite removal rates were achieved to be 13.82 and 16.311 kg/(m3 day), respectively, at 0.10 day HRT. The process can endure high sulfide concentrations, as the sulfide removal percentage always remained higher than 88.97% with influent concentration up to 1920 mg/L. Incomplete sulfide oxidation took place due to lower consumed nitrite to sulfide ratios of 0.93. It also tolerated high nitrite concentration up to 2265.25mg/L. The potential achieved by decreasing HRT at fixed substrate concentration is higher than that by increasing substrate concentration at fixed HRT. The process can bear short HRT of 0.10 day but careful operation is needed. Nitrite conversion was more sensitive to HRT than sulfide conversion when HRT was decreased from 1.50 to 0.08 day. Stoichiometric analyses and results of batch experiments show that major part of sulfide (89-90%) was reduced by nitrite while some autooxidation (10-11%) was resulted from presence of small quantities of dissolved oxygen in the influent wastewater. There was ammonia amassing in considerably high amounts in the bioreactor when the influent nitrite concentration reached above 2265.25mg/L. High ammonia concentrations (200-550 mg/L) in the bioreactor contributed towards the overall inhibition of the process. Present biotechnology exhibits practical value with a high potential for simultaneous removal of nitrite and sulfide from concentrated wastewaters at shorter HRT.  相似文献   
296.
In this paper, we apply Homotopy Analysis Method (HAM) to find appropriate solutions for the Zakharov–Kuznetsov equations with fully nonlinear dispersion which are of utmost importance in applied and engineering sciences. Numerical results re-confirm the reliability of the proposed algorithm (HAM).  相似文献   
297.
Cobalt-oxide nanoparticles (NPs) were fabricated using Punica granatum peel extract from cobalt nitrate hexahydrate at low temperature. The synthesized cobalt-oxide NPs were characterized using X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray, atomic force microscopy, fourier transform infrared spectroscopy and UV-visible techniques. The cobalt-oxide NPs were in highly uniform shape and size was in the size of 40–80 nm. Photo-catalytic activity (PCA) of the synthesized NPs was evaluated by degrading Remazol Brilliant Orange 3R (RBO 3R) dye and a degradation of 78.45% was achieved (dye conc. 150 mg/L) using 0.5 g cobalt-oxide NPs for 50 min irradiation time. In view of eco-benign and cost-effective nature, the present investigation revealed that P. granatum could be used for the synthesis of cobalt-oxide NPs for photo-catalytic applications.  相似文献   
298.
Copy-move forgery is the most common type of digital image manipulation, in which the content from the same image is used to forge it. Such manipulations are performed to hide the desired information. Therefore, forgery detection methods are required to identify forged areas. We have introduced a novel method for features computation by employing a circular block-based method through local tetra pattern (LTrP) features to detect the single and multiple copy-move attacks from the images. The proposed method is applied over the circular blocks to efficiently and effectively deal with the post-processing operations. It also uses discrete wavelet transform (DWT) for dimension reduction. The obtained approximate image is distributed into circular blocks on which the LTrP algorithm is employed to calculate the feature vector as the LTrP provides detailed information about the image content by utilizing the direction-based relation of central pixel to its neighborhoods. Finally, Jeffreys and Matusita distance is used for similarity measurement. For the evaluation of the results, three datasets are used, namely MICC-F220, MICC-F2000, and CoMoFoD. Both the qualitative and quantitative analysis shows that the proposed method exhibits state-of-the-art performance under the presence of post-processing operations and can accurately locate single and multiple copy-move forgery attacks on the images.  相似文献   
299.
In the current research work Ba_(1-x)La)xMn)yFe_(12-y)O_(19) hexa-ferrite nanoparticles of different compositions were synthesized using chemical co-precipitation technique. The structural properties were explored using X-ray diffractions(XRD), scanning electron microscopy(SEM) and Fourier transmission infrared spectroscopy(FTIR). XRD indexed pattern confirms the formation of M-type hexagonal phase. The crystallite size of synthesized samples ranges from 13 to 34 ± 2 nm. FTIR peaks observe also confirmed the presence of metaloxygen bond of the desired product. The position of peak at 467 cm~(-1) corresponds to A_2 u vibration for octahedral Fe(4+)-O and peak position E1 u corresponds to vibration of Fe(3+)O4 octahedral bonds. The band v_1 in range(677-559 cm~(-1)) and v_2 in frequency range(356-419 cm~(-1)) are associated to A and B sites.Dielectric properties of all compositions were measured with frequency. The dielectric constant, loss and tangent loss decrease from 26 to 9, 25 to 2 and 0.94 to 0.14, respectively with frequency. DC electrical resistivity is increased with dopant concentration increasing from 2.15 × 10~4 to 1.92 ×10~5 Ω·cm.  相似文献   
300.
In this paper, a discrete mathematical model of a magnetic electrospinning process is established and used to analyze numerically the effect of excitation current on electrospinning instability. The charged jet is assumed to be discrete electrified particles, which are joined by viscous flexible materials. The simulation results agree well with the experimental data and show that the magnetic approach provides an effective way to control instability.  相似文献   
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