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Quantum Mechanical Calculations for the Misincorporation of Nucleotides Opposite Mutagenic 3,N4‑Ethenocytosine
No full textThe ubiquitous nature and persistence of
exocyclic DNA adducts suggest their involvement as initiators
of carcinogenesis. We have investigated the misincorporation
properties of the exocyclic DNA adduct, 3,N4-ethenocytosine,
using DFT and DFT-D methods. Computational investigations
have been carried out by using the B3LYP, M062X, and
wB97XD methods with the 6-31+G* basis set to determine
the hydrogen bonding strengths, binding energy, and physical
parameters. The single point energy calculations have been
carried out at MP2/6-311++G** on corresponding optimized
geometries. The energies were compared among the 3,N4-
ethenocytosine adduct with DNA bases to find the most stable
conformer. The solvent phase calculations have also been carried out using the CPCM model. The computed reaction enthalpy
values provide computational insights to the earlier experimental observation in in vitro, E.coli, and mammalian cells of a high
level of substitution mutation in which C → A transversion results from εC−T pairing [εC−T3 and εC−T4] in the adduct
containing DNA sequence
Microvascular Complications and Their Associated Risk Factors Among Rural Type 2 Diabetic Population: A Cross-Sectional Study
Get PDFTo determine the factors associated with progression of microvascular complications in T2DM patients and also to investigate the relationship between glycated hemoglobin (HbA1c, %) levels and risk factors associated with microvascular complications. A cross-sectional study was conducted in the rural area of Guntur, Andhra Pradesh, India. A total of 64 subjects with the history of T2DM more than 5-year duration were included in the study. Micro-albuminuria, fundoscopy examination, and other biochemical parameters were assessed to rule out nephropathy and retinopathy. Out of the total 64 subjects, 48 (75%) were males and 16 (25%) were females. The mean age among the subjects was 57.9 ± 8.3 years. A strong association between poor glycemic control and progression of non-proliferative diabetic retinopathy (NPDR) and severely increased urinary albumin-creatinine ratio (UACR, mg/g) and diabetic nephropathy (DN) (p = 0.018, OR 3.95, and 95% CI 1.22, 12.78 and p = 0.0005, OR 6.5, and 95% CI 2.7.19.48) was observed. The level of education, annual income, and body mass index (BMI, kg/m2
) are strongly associated with the development of NPDR (p < 0.05), and annual income, hypertension, and duration of T2DM are the influencing progression of micro-albuminuria (p < 0.05). The risk of developing NPDR, DN, and poor glycemic control among hypertensives (OR 1.5, 0.6, and 0.7) are more compared to normotensives. Some risk factors were not significant. The level of education, annual income, duration of diabetes, and BMI are the major risk factors for the progression of NPDR and also poor glycemic control that provokes to microvascular complications. Interventions are needed to regulate glycemic control to prevent or reverse the further progression of these complications
Design, multistep synthesis and in-vitro antimicrobial and antioxidant screening of coumarin clubbed chalcone hybrids through molecular hybridization approach
Get PDFIn the present study we designed and synthesized 26 coumarin clubbed chalcone hybrids (1–13 and 14–26) in good yields (54.32–74.25%) and further tested for their antimicrobial and antioxidant activities considering the potential bioactivities of these two pharmacophores. All Spectroscopic techniques including FT-IR, 1 H NMR, 13C NMR and mass were used to characterize the compounds. The antimicrobial and antioxidant activities of these compounds were performed by agar well diffusion method and DPPH free radical assay respectively. The compounds elicited considerable antimicrobial and potential antioxidant activities. Bioactivity data designated that the compounds 1 and 7 with no and 4-Cl substitution on the phenyl ring of coumarin clubbed chalcones with 3,4-dihydropyrimidine-2-one displayed antibacterial activity with minimum inhibitory concentration (MIC) value of 10 mM and 17 mM against Staphylococcus aureus and MIC value of 8 mM and 13 mM against Escherichia coli and antifungal activity with MIC value of 10 mM and 11 mM against Aspergillus niger respectively. On the other hand, coumarin clubbed chalcones with 3,4-dihy dropyrimidine-2(1H)-thione scaffold (14–26) exhibited potential antioxidant activity. Among them, compounds 22 containing electron releasing 2-OH substituent was the most active with 77.92% scavenging activity, followed by 14 and 26 (75.22% and 71.32%). The promising leads evolved through this investigation are important for the future development of novel and potential antioxidant compounds
Single Image Haze Removal Based on transmission map estimation using Encoder-Decoder based deep learning architecture
Get PDFHaze removal is an essential requirement in autonomous vehicle applications for identifying different objects on the road. Most of the available techniques are based on different constraints/ priors. The important parameters required for recovering the ground truth from hazy image are transmission map and air light. In this paper, we proposed a learning-based Encoder-Decoder deep learning architecture for transmission map estimation. Based on the assumption that at least twenty percent of the outdoor image includes with sky region and hence airlight is calculated as average of the twenty percent brightest pixels of the image. These two parameters namely transmission map and airlight were applied in atmospheric scattering model for ground truth image recovery. In Encoder-Decoder architecture, Max pooling layer, dropout layer was used for feature learning and efficient generalization respectively. The proposed architecture was trained on different datasets like NYU Depth data set, FRIDA and RESIDE Dataset for better generalization on unseen data. Experimental results shows that the proposed method has shown better performance compared to the existing state of the art method
Design and Implementation of High Performance PPSK demodulator in Biomedical Implant
Get PDFBackground/Objective: The important challenge for the realization of hearing aids is small size, low cost, low power consumption, and better performance, etc. Keeping these requirements in view this work concentrates on the VLSI (Very Large Scale Integrated) implementation of the analog circuit that mimics the PPSK (Passive Phase Shift Keying) demodulator with a low pass filter.
Methodology: This research deals with RF Cochlear implant circuits and their data transmission. A PPSK modulator is used for uplink data transmission in biomedical implants with simultaneous power, data transmission. This study deals with the implementation of a PPSK demodulator with related circuits and a low pass filter which are used in cochlear implants consumes low power and operates at 14MHz frequency. These circuits are designed using FINFET 20nm technology with 0.4v DC supply voltage. Findings: The performance of the proposed design over the previous design is operating at low threshold voltage, reduces static leakage currents, and often observed greater than 30 times of improvement in speed performance Novelty: As the conventional design with the same supply voltage(0.4v) exhibit high power dissipation and delay and require more amount of time to demodulate the signal. Whereas the proposed FINFET based monostable circuit and PPSK demodulator with a low pass filter has proven better in terms of less delay and power dissipation and can transmit the data with less bit error rate in stipulated time
Activation of oxygen reduction reaction on carbon supported Ni-based complexes
No full textThere are unremitting efforts towards developing an effective oxygen reduction reaction (ORR) catalyst as it is seminal for the commercially viable energy conversion and storage devices such
as fuel cell and metal-air batteries. In this study, three carbon-supported Ni-based coordination complexes; Ni-phen/AC, Ni-bpy/AC and Ni-bimz/AC (where phen=1,10- Phenanthroline,
bpy= 2, 2'-bipyridine and bimz= Benzimidazole) were explored for ORR. Among these, Nibimz forms a 1D-polymer chain via a succinate bridge, and these chains are stacked by the ππ interactions and hydrogen bonding. The ORR potentials of these catalysts were studied using cyclic voltammetry technique with a rotating ring disk electrode system, and oxygen adsorption
energies (Ead) onto these complexes were calculated using density functional theory (DFT) analysis. The highest onset potential of 0.89 V vs. RHE was observed for Ni-bimz/AC, whereas 0.88 V and 0.86 V vs. RHE for Ni-phen/AC and Ni-bpy/AC catalysts, respectively. The Ead value for O2 via side-on and end-on mode over Ni-phen, Ni-bpy, and Ni-bimz complexes, were calculated. The highest negative Ead value of -25.53 eV via side-on mode was observed for Ni-bimz complex
Application of stimuli-responsive FRET behavior toward cyanide detection in a photo-switchable [2] pseudorotaxane polymer containing the BODIPY donor and the merocyanine acceptor
No full textWe have developed a supramolecular (close form) [2]pseudorotaxane polymer containing the green�emissive (lem = 523 nm) BODIPY-based pillar[5]arene host and the non-emissive spiropyran (SP)-based cyano guest (close form), which can be converted to a red-emissive (lem = 630 nm) merocyanine
(MC)-based guest (open form) upon UV exposure as well as turned into a bi-fluorophoric host–guest polymer with ratiometric PL emission of Fo¨rster resonance energy transfer (FRET) behavior in THF/water solution (60% H2O, v/v) . The equal host–guest molar ratio and the formation of the [2]pseudorotaxane polymer can be further verified using 1
H NMR titration, Job’s plot analysis, DOSY and ITC experiments.
Hence, the bi-fluorophoric host–guest (with the MC open form) polymer possessed the highest red-emission of the MC acceptor, which was also confirmed using TRPL measurements to possess the shortest lifetime of 0.37 ns and the best FRET efficiency of 83.5%. Since the MC unit could react with CN� to induce a non�emissive quenching process, the mono-fluorophoric guest would show turn-off PL behavior and detect cyanide
ions with a corresponding limit of detection (LOD) value of 0.94 mM. In comparison, the optimal LOD value of 0.48 mM toward CN� anion could be achieved by our bi-fluorophoric host–guest polymer via the FRET-OFF process. Therefore, cyanide detection and cell viability tests using the open form of the 2]pseudorotaxane polymer suggest useful bio-imaging applications in living cell
Modeling and multi response optimization of mechanical properties for E-glass/polyester composite using Taguchi-grey relational analysis
No full textIn the present work, E-glass/polyester composite laminates were manufactured in a customized resin transfer mould
(RTM) with different layers of fiber at selected resin injection pressures. Experiments were performed employing full
factorial design to study the influence of number of fiber layers and resin injection pressure on mechanical properties of
the composites. Analysis of variance was implemented to study the interaction effect of process parameters on multiresponses namely tensile, flexural and impact strengths. Taguchi method based grey relational analysis was used to determine optimal control factors for the responses. Numbers of fiber layers and the injection pressure have significance with respective 73.96% and 16.57% contributions on the grey relation grades of the three responses. An optimal working condition was suggested to produce quality composite. In addition, mathematical models for the mechanical properties were also developed using the experimental result
Stable Cobalt Porphyrin Obeyed Type Small Molecule Sensor For The Sensitive And Selective Detection Of Ammonia Gas At Room Temperature
No full textAbstractThe ammonia (NH3) gas device sensors at room temperature rapid‐response (RTRR) selective discovery is a challenging and massive task that is restricted due to reduced room‐temperature (RT) detecting materials and their unsatisfactory gas detecting performance features. In this work, an organic small molecule 5, 10, 15, 20‐tetrakis {4‐[N,N‐di(4‐methoxyphenyl) amino‐phenyl]‐porphyrin (PO) and its cobalt complex cobalt‐porphyrin (PCo) based twisted type structure sensor is established for the detection of NH3 gas at RT. Interestingly, the introduction of Co atom into porphyin ring center increases overall performance, including high stability maximum response of 85% to 20 ppm NH3, and high selectivity towards ammonia compared to PO molecule. In terms of selectivity, the PCo sensor has a great affinity for NH3 due to the unpaired electron in dx2‐y2 with the porphyrin‐system, which boosts NH3 selectivity even in a mixture of gases. The detection range is 1 ppm, which is an 11% response with outstanding fast response (180 s) and recovery (10 s) containing excellent reproducibility to 20 ppm NH3. The superior gas‐detecting characteristics of PCo are ascribed to the interface between NH3 and cobalt Co‐group of PCo. The results from sequential studies deliver a novel approach and procedure for exploring RT ammonia gas device sensors
An improved hybrid secure multipath routing protocol for MANET
No full textMobile ad hoc networks (MANETs) are self-organizing nodes in a mobile network that
collaborate to form dynamic network architecture to establish connections. In MANET, data must traverse
several intermediary nodes before reaching its destination. There must be security in place to prevent hostile nodes from accessing this data. Multiple methods were suggested in literature for securing routing; these techniques tackle different aspects of security. In order to enhance fault tolerance, wireless network multipath routing is typically used instead of the original single path routing. The routing protocol Genetic Algorithm with Hill climbing (GAHC) described in this article shows a hybrid GA-Hill Climbing algorithm that picks the optimal route in multipath. Prior to this in the beginning, the Improved fuzzy C-means algorithm method was built on density peak, and cluster heads (CHs) were chosen in a predicted manner, based on recent, indirect, and direct trust. The computation is based worth nodes are at the trust threshold found in addition. Even CHs take part in the alternate paths, the blend of all the many paths from these Cluster Heads
that chooses the optimal route, which is based on the predicted hybrid protocol, as well as the optimum route’s aggregate features such as throughput, latency, and connection. This suggested technique requires a minimum amount of energy of 0.10 m joules and a small amount of delay time of 0.004 msec, which also yields a maximum throughput of 0.85 bits per second, a maximum detection rate of 91 percent and
maximum packet delivery ratio of 89percent. The suggested approach was put through the paces with the selective packet dropping attac