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71.
Nikhil Verma Harpreet Singh Divya Khanna Prashant Singh Rana Sanjay Kumar Bhadada 《IET systems biology》2019,13(5):243
In humans, oxidative stress is involved in the development of diabetes, cancer, hypertension, Alzheimers’ disease, and heart failure. One of the mechanisms in the cellular defence against oxidative stress is the activation of the Nrf2‐antioxidant response element (ARE) signalling pathway. Computation of activity, efficacy, and potency score of ARE signalling pathway and to propose a multi‐level prediction scheme for the same is the main aim of the study as it contributes in a big amount to the improvement of oxidative stress in humans. Applying the process of knowledge discovery from data, required knowledge is gathered and then machine learning techniques are applied to propose a multi‐level scheme. The validation of the proposed scheme is done using the K‐fold cross‐validation method and an accuracy of 90% is achieved for prediction of activity score for ARE molecules which determine their power to refine oxidative stress.Inspec keywords: cancer, cellular biophysics, biochemistry, drugs, molecular biophysics, proteins, learning (artificial intelligence), medical computingOther keywords: oxidative stress, Nrf2‐antioxidant response element signalling pathway, ARE signalling pathway, diabetes, cancer, hypertension, Alzheimers’ disease, heart failure, machine learning techniques, K‐fold cross‐validation method, ARE molecules 相似文献
72.
Influence of alkyl (C12–C14)-dimethyl-benzyl ammonium chloride in the solution of sodium hydroxide on the hydrolysis of poly(ethylene terephthalate) (PET), anionically modified poly(ethylene terephthalate) copolyster (CDP), and block polymer of poly(ethylene terephthalate)-poly(ethylene glycol) (EDP), has been studied under a variety of proportions, concentrations, time and temperature of reaction, M : L ratio, etc. Mechanical properties of treated polymeric materials are evaluated. Hydrolysis of two polymers in the same bath is compared with that in separate baths. 相似文献
73.
Ashok Kumar Singh N. Chaurasia Shahla Rahmani Jaya Srivastava Bharat Singh 《Catalysis Letters》2004,94(3-4):135-141
The NO/H2 reaction has been studied over a Ni loaded carbon film catalysts using in situ FTIR spectroscopy at the temperature range 25–350°C. On these catalysts, the differences in activity and selectivity were found depending on the nature of the surface functional groups. These differences were correlated with transient infrared spectral features which appeared during the reaction. It has been proved experimentally that the chemical character of the support is of vital importance during the process. The rise in NO conversion and N2 selectivity was observed when the surface of the catalysts was changed by the NH3 chemisorption. Amide and/or imide species formed due to the reduction of ammonium salts of carboxylic acids can play a significant role as active centers during the NO reduction. 相似文献
74.
The carbon nanotube field-effect transistor (CNFET) is emerging as one of the most promising alternatives to complementary metal–oxide–semiconductor (CMOS) transistors due to its one-dimensional (1-D) band structure, low off-current capability, near-ballistic transport operation, high stability, and low power consumption. This paper presents the design of a CNFET-based ternary content-addressable memory (TCAM) cell and rigorously analyzes its performance in terms of power–delay product (PDP) and static noise margin (SNM). The effect of variations of the chiral vector on the performance of the TCAM cell is also comprehensively investigated. While selecting the chirality, SNM, PDP, and search time are considered as figures of merit. In this TCAM cell design, we apply the same chirality for all CNFETs of the same type. Extensive HSPICE simulations have been performed for computation of performance parameters using the Stanford University CNFET model. Comparison of CNFET- and CMOS-based TCAM cells has been carried out at the 16-nm technology node. The results show that the CNFET-based TCAM cell exhibits significant improvements of PDP, i.e., by 38 % during write operation and 98 % during search operation, and 53 % in SNM, compared with its CMOS counterpart. It is also observed that the best chirality for the TCAM cell design is (22, 19, 0) or (10, 19, 0) from the point of view of SNM and PDP, respectively. 相似文献
75.
Snehalkumar Parmar Kamal K. Pant Mathew John Kishore Kumar Shivanand M. Pai Shalini Gupta Bharat L. Newalkar 《Journal of Porous Materials》2014,21(5):849-857
Hydroisomerization of n-hexadecane is performed over ZSM-12 framework having tailored Brønsted acidity to investigate the effect in terms of product selectivity and yield. For this purpose, pure phase of ZSM-12 (bulk molar ratio Si/Al ~ 60) has been synthesized using TEABr as a structure directing agent. The framework Brønsted acidity is tailored with group II elements (M) viz. Ca, Ba and Mg, by means of ion-exchange method. The samples so prepared have been characterized for phase purity, textural parameters, morphology by employing powder X-ray diffraction, nitrogen adsorption–desorption isotherm measurement at 77 K, and scanning electron microscopy technique, respectively. Similarly, % metal exchange is estimated using inductively coupled plasma technique. The quantification of Brønsted acidity for H+–M++–ZSM-12 samples has been estimated by means of ammonia temperature programmed desorption (NH3-TPD) and Fourier transform infrared spectroscopy of ammonia (NH3-FTIR). The well characterized H+–M++–ZSM-12 samples were loaded with Platinum (Pt, 0.5 wt%) and subjected to hydroisomerization of n-hexadecane using an up-flow fixed bed reactor to verify the effect of process parameters like temperature and WHSV. Pt/H+–Ba2+–ZSM-12 with tailored Brønsted acidity in the range of about 25 % demonstrated the optimum performance among all the catalysts with an increased isomer selectivity and yield (89.2 and 80.3 %, respectively) by about 4 wt% at a conversion level of about 90 % compared to Pt/H+–ZSM-12 framework at 568 K. Such enhancement in isomer selectivity and yield is found to be significant from commercial application point of view. Based on the obtained trend, the potential benefits of implementation of Pt/H+–Ba2+–ZSM-12 (bulk molar ratio Si/Al ~ 60) framework for cold flow property improvement of ‘bio-ATF’ have been envisaged. 相似文献
76.
Bharat Ugale C. M. Nagaraja 《Journal of Inorganic and Organometallic Polymers and Materials》2014,24(6):1032-1037
A new metal–organic framework of Zn(II) ion, [Zn(muco)(bipy)·2H2O] (where, muco = trans, trans-muconate dianion, bipy = 4,4′-bipyridine) has been synthesized by solvothermal reaction of Zn(II) ion, muco ligand and bipy spacer. X-ray structure determination reveals that compound 1 has a 3D diamondoid (dia) framework with novel fivefold interpenetrating nets. Topological analysis shows the presence of 4-connected Zn(II) nodes with {66} topology. Thermal analysis reveals that the compound is stable up to 340 °C. Photoluminescence study shows the emission of 1 owing to the presence of muco ligand and the intensity of luminescence emission is higher than that of free muco ligand. 相似文献
77.
Christabelle Rajesh Satish Sagar Ashok Kumar Rathinavel Divya Thomas Chemparathy Xianlu Laura Peng Jen Jen Yeh Michael A. Hollingsworth Prakash Radhakrishnan 《International journal of molecular sciences》2022,23(10)
Elevated levels of Mucin-16 (MUC16) in conjunction with a high expression of truncated O-glycans is implicated in playing crucial roles in the malignancy of pancreatic ductal adenocarcinoma (PDAC). However, the mechanisms by which such aberrant glycoforms present on MUC16 itself promote an increased disease burden in PDAC are yet to be elucidated. This study demonstrates that the CRISPR/Cas9-mediated genetic deletion of MUC16 in PDAC cells decreases tumor cell migration. We found that MUC16 enhances tumor malignancy by activating the integrin-linked kinase and focal adhesion kinase (ILK/FAK)-signaling axis. These findings are especially noteworthy in truncated O-glycan (Tn and STn antigen)-expressing PDAC cells. Activation of these oncogenic-signaling pathways resulted in part from interactions between MUC16 and integrin complexes (α4β1), which showed a stronger association with aberrant glycoforms of MUC16. Using a monoclonal antibody to functionally hinder MUC16 significantly reduced the migratory cascades in our model. Together, these findings suggest that truncated O-glycan containing MUC16 exacerbates malignancy in PDAC by activating FAK signaling through specific interactions with α4 and β1 integrin complexes on cancer cell membranes. Targeting these aberrant glycoforms of MUC16 can aid in the development of a novel platform to study and treat metastatic pancreatic cancer. 相似文献
78.
S. Swarupa Tripathy Swati Gupta Divya Mishra Praveen Kumar Yadav Sunita Raina Rajiv K. Saxena Niranjan Singh Nahar Singh Monika J. Kulshrestha V. N. Ojha R. K. Kotnala 《Mapan》2020,35(1):111-115
Breath alcohol analyser is used to detect alcohol content in end-expiratory breaths in order to enforce driving regulations under the influence of alcohol legislation. The accuracy and reliability of the routine measurements of alcohol content performed with breath alcohol analyser can be achieved by the calibration of the breath alcohol analyser using standards traceable to SI reference material. Proper calibration is essential for transparency in legal verification for which reference material is needed. At international level, a number of NMIs are active to address this important measurement issue of providing accurate measurements. Several international key comparison programs have been organized so far for the determination of ethanol content in aqueous and in nitrogen/air matrix. NIST, USA; BAM, Germany; IRMM, Belgium, Portugal, INMETRO, Brazil, LGC, UK etc. have developed certain reference materials of ethanol in water solution/air with different concentration ranges. However, no such reference material is introduced in India as an indigenous standard, rather, being procured from abroad or using high purity alcohol for calibration purposes. CSIR-NPL, India, being the NMI is now focusing on establishing the calibration facility and development of SI traceable aqueous alcohol standard to provide test reliability for the testing in breath alcohol analyser. This program has a societal impact which contributes to human health and regulatory needs for the nation. 相似文献
79.
Solid particle erosion, electrical-arc-induced wear, fretting corrosion and fretting wear modes were studied. Scanning electron microscope examinations generally show significant differences in the different wear modes. Further scanning and transmission electron microscope examinations of the cross sections of worn samples show very little, if any, plastic deformation near the worn surfaces. Microhardness measurements on the cross section of arced samples show an increase of about 25% near the worn surface. Surface analysis of fretting and fretting corrosion wear samples show the existence of an adherent layer that is heavily oxidized in most cases. The source of the adherent layer can be either of the two mating surfaces. It was also found that the same surface may undergo both loss of the original surface layer and gain of an adherent layer. The metallurgical techniques described in this paper can be successfully used to diagnose the wear of solid surfaces. 相似文献
80.
Ajay Arora Divya Choudhary Gaurav Agarwal Virender Pal Singh 《International Journal of Food Science & Technology》2008,43(11):1913-1921
Banana is one of the most important tropical fruits, and India ranks first in its world production. Banana cultivars rich in provitamin A carotenoids may offer a potential food source for alleviating vitamin A deficiency, particularly in developing countries. With a view to exploit banana peels as a source of valuable components, in the present study, proximate composition, carotenoids, beta‐carotene and some anti‐oxidative enzymes as well as carbohydrate content of selected Indian banana varieties were determined. Karpooravalli cultivar of banana showed the maximum accumulation of carotenoid content in the non‐edible (68 μg g?1 d.w.) portion of banana, while being the second highest in beta‐carotene content (143.12 μg per 100 g). However, Red Banana ranked highest in total carotenoid contents for pulp (4 μg g?1 d.w.) and beta‐carotene was estimated to be the highest in the case of peels (241.91 μg per 100 g) and in pulp (117.2 μg per 100 g). Karpooravalli cultivar of banana is also rich in carbohydrate content in terms of total starch (1786.0 μg g?1 d.w. in peels and 544.85 μg g?1 d.w. in pulp) and sugars (53.53 μg g?1 d.w. in peels and 39.05 μg g?1 d.w. in pulp). The catalase enzyme activity in these peels ranged from 5.66 to 35.57 nmol min?1 mg?1 proteins and was found at a higher level in cultivar Poovan, while the ascorbate peroxidase showed the range of 2.25 to 6.22 μmol min?1 mg?1 proteins. The peels of cultivars Red Banana and Karpooravalli are rich source of bioactive compounds, such as carotenoids (beta‐carotene), anti‐oxidative enzymes and carbohydrate contents. 相似文献