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Four species of Lejeunea viz., L. discreta, L. kashyapii, L. mehrana and L. parva are reported here for the first time from Meghalaya. Of which, Lejeunea kashyapii and L. mehrana are endemic, earlier reported from Sikkim only. The taxonomic description and illustrations of all are provided in present communication.

Open access

Summary

A stability-indicating gradient reverse-phase liquid chromatographic method was developed for the quantitative determination of process-related impurities and forced degradation products of oxcarbazepine in pharmaceutical formulation. The method was developed by using Inertsil cyano (250 × 4.6 mm) 5 μm column with mobile phase containing a gradient mixture of solvent A (0.01 M sodium dihydrogen phosphate, pH adjusted to 2.7 with orthophosphoric acid and acetonitrile in the ratio of 80:20 v/v) and B (50:40:10 v/v/v mixture of acetonitrile, water, and methanol). The flow rate of mobile phase was 1.0 mL min−1. Column temperature was maintained at 25°C and detection wavelength at 220 nm. Developed reverse-phase high-performance liquid chromatography (RP-HPLC) method can adequately separate and quantitate five impurities of oxcarbazepine, namely imp-A, imp-B, imp-C, imp-D, and imp-E. Oxcarbazepine was subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal, and photolytic degradation. Oxcarbazepine was found to degrade significantly in acid, base, and oxidative stress conditions. The degradation products were well resolved from oxcarbazepine and its impurities. The developed method was validated as per International Conference on Harmonization (ICH) guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision, and robustness.

Open access

Abstract

In this paper, advanced DC-Link (DCL) based reversing voltage type Multilevel Inverter (MLI) topologies by compensating the difficulties in the conventional MLIs are reviewed. These topologies consist of less switching components and driver circuits when compared with conventional MLIs predominantly in higher levels. Consequently, installation area, total cost and hardware difficulties are reduced by increasing the voltage levels. The unipolar based Pulse Width Modulation Schemes (PWMS) will improve DCL inverters performance. This paper presents unipolar Multi-Reference (MR) based sine and space vector PWMS with single triangular carrier wave for generating required levels in output voltage. Comparison between UMR sine and space vector PWMS for DCL inverter topologies is presented in terms of Fundamental Output Voltage (FOV) and Total Harmonic Distortion (THD). The research tries to establish the survey analysis for single-phase 7-level DCL based reversing voltage type MLI topologies with UMR based sine and space vector PWMs. Finally, to confirm the feasibility of proposed DCL-MLIs in terms of FOV and THD the simulation results are incorporated. Further, the prototype model is developed for single-phase 7-level DCL inverter with Field Programmable Gate Array (FPGA) based UMR sine and space vector PWMS to authenticate simulation results. The efficiency of the proposed cascaded MLI achieves the value of 99.003%.

Open access

Abstract

In this manuscript, the combination of IoT and Multilayer Hybrid Dropout Deep-learning Model for waste image categorization is proposed to categorize the wastes as bio waste and non-bio waste. The input captured images are pre-processed and remove noises in the captured images. Under this approach, a Nature inspired Multilayer Hybrid Dropout Deep-learning Model is proposed. Multilayer Hybrid Dropout Deep-learning Model is the consolidation of deep convolutional neural network and Dropout Extreme Learning Machine classifier. Here, deep convolutional neural network is used for feature extraction and Dropout Extreme Learning Machine classifier for categorizing the waste images. To improve the classification accurateness, Horse herd optimization algorithm is used to optimize the parameter of the Dropout Extreme Learning Machine classifier. The objective function is to maximize the accuracy by minimize the computational complexity. The simulation is executed in MATLAB. The proposed Multilayer Hybrid Dropout Deep-learning Model and Horse herd optimization algorithm attains higher accuracy 39.56% and 42.46%, higher Precision 48.74% and 34.56%, higher F-Score 32.5% and 45.34%, higher Sensitivity 24.45% and 34.23%, higher Specificity 31.43% and 21.45%, lower execution time 0.019(s) and 0.014(s) compared with existing waste management and classification using convolutional neural network with hyper parameter of random search optimization algorithm waste management and classification using clustering approach with Ant colony optimization algorithm. Finally, the proposed method categorizes the waste image accurately.

Open access

Summary

A simple, selective, and stability-indicating reverse phase liquid chromatographic method has been developed and validated for the simultaneous determination of impurities and forced degradation products of quetiapine fumarate. The chromatographic separation was achieved on Inertsil-3 C8, 150 mm × 4.6 mm, 5 μm column at 35°C with UV detection at 217 nm using gradient mobile phase at a flow rate of 1.0 mL/min. Mobile phase A contains a mixture of 0.01 M di-potassium hydrogen orthophosphate (pH 6.8) and acetonitrile in the ratio of 80:20 (v/v), respectively, and mobile phase B contains a mixture of 0.01 M di-potassium hydrogen orthophosphate (pH 6.8) and acetonitrile in the ratio of 20:80 (v/v), respectively. The drug product was subjected to the stress conditions of oxidative, hydrolysis (acid and base), hydrolytic, thermal, and photolytic degradation. Quetiapine fumarate was found to degrade significantly in acid, base, and oxidative stress conditions. The degradation products were well resolved from main peak and its impurities. The mass balance was found to be in the range of 96.6–102.2% in all the stressed conditions, thus proved the stability-indicating power of the method. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision, and robustness.

Open access

Summary

Root exudates were obtained from three mangrove species, viz. Bruguiera gymnorrhiza, Excoecaria agallocha, and Heritiera fomes. Spot tests revealed the presence of, presumably, phenolic compounds in the exudates. Paper chromatography revealed two spots each for B. gymnorrhiza and H. fomes and a single spot for E. agallocha. GC-MS analysis suggested the presence of aminopyrine, palmitic acid, stearic acid, di-n-propyl ether, and 2,5-anhydrogluconic acid in B. gymnorrhiza exudates, aminopyrine and palmitic acid in E. agallocha exudates, and aminopyrine, palmitic acid, and 2,5-anhydrogluconic acid in H. fomes exudates.

Open access
International Review of Applied Sciences and Engineering
Authors:
K. S. Ajay Venkadesh
,
K. Harish Kumar
,
B. Hariharan
,
A. Arumugam
,
A. Nithish Kumar
,
P. Karthigai Priya
, and
S. Vanitha

Abstract

Raw materials requirement is foremost necessary in construction sector. Due to the increase in construction activities, the raw material utilization is also increased, which may lead to depletion of the resources. The usage of M sand also increases day by day. On the other side, waste disposal is posing a major threat to environment and human health. This paper shows the investigation carried out in manufacturing fly ash bricks made by utilizing vermicompost as an alternative material for M sand, the physical and chemical properties of M sand and vermicompost are studied and they seem to be the same. In this study, an attempt is made to check the feasibility of replacement of vermicompost for M sand in brick making. The brick specimens are casted as per the mix proportions and they are tested for strength and durability at the age of 28 days. It has been identified that the vermicompost replacement at 5% and 10%, the compressive strength of the brick is 7.90 and 7.31% respectively, which is found to be nearer to the strength of the control specimen and the water absorption for all the mixes of the brick casted were below 20% as per IS code. Inclusion of vermicompost in the fly ash bricks will tend to reduce the use of M sand.

Open access
Acta Chromatographica
Authors:
M. Ganesh
,
B. Thangabalan
,
R. Patil
,
D. Thakur
,
A. Kumar Kumar
,
M. Vinoba
,
S. Ganguly
, and
T. Sivakumar

Summary

A rapid, simple and validated reversed-phase high-performance liquid chromatographic method has been developed for analysis of oxaprozin in pharmaceutical dosage forms. Oxaprozin was separated on an ODS analytical column with a 45:55 (v/v) mixture of acetonitrile and triethanolamine solution (5 mm, pH 3.5 ± 0.05, adjusted by addition of 85% phosphoric acid) as mobile phase at a flow rate of 2.0 mL min–1. The effluent was monitored by UV detection at 254 nm. Calibration plots were linear in the range 160 to 240 μg mL–1 and the LOD and LOQ were 14.26 and 41.21 μg mL–1, respectively. The high recovery and low relative standard deviation confirm the suitability of the method for routine QC determination of oxaprozin in tablets.

Open access

Abstract

Background

Pulmonary Arterial Hypertension (PAH) carries a poor prognosis in both adult and pediatric patients. It is a life-threatening condition in newborns. Current recommendations advocate the use of targeted monotherapy as a first-line approach for the treatment of Persistent Pulmonary Hypertension of the Newborn (PPHN). In case of an inadequate clinical response to treatment, an addition of a second or third agent is considered. PAH is usually managed with a phosphodiesterase 5 inhibitor or an endothelin receptor blocker. There are limited pediatric studies that address questions like which class of therapy should be initiated first or if a combination should be initiated together. With this background, the present study was initiated to compare the efficacy, safety, and tolerability of bosentan as an adjuvant to sildenafil and sildenafil alone in PPHN.

Results

A total of 40 patients were enrolled in the study. Out of them, 26 were males (65%) and 14 were females (35%). PPHN was most commonly seen in the 29 (72.5%) of participants with a history of first order birth. Mean duration of symptoms was 14.05 ± 2.06 days. The participants were randomized to two groups. Group A consisted of total 25 participants that received both bosentan and sildenafil and group B had 15 participants that received sildenafil alone. Both groups were comparable in terms of birth weight and present weight, consanguinity, and mode of delivery. Efficacy was determined by the reduction in mean baseline Pulmonary Artery Systolic Pressure (PASP). PASP in group A was 75.56 ± 10.62 mm Hg and in group B was 64.86 ± 12.25 mm Hg which was not statistically significant (P > 0.05). PASP on the third and seventh day in group A were 43.72 ± 8.63 and 24.47 ± 3.52 mm Hg compared to 42.28 ± 9.43 and 27.276 ± 8.38 respectively in group B which was statistically significant (P < 0.05).There were two deaths each in both groups. Two participants in Group A developed liver function abnormalities. None of the participants in Group B had adverse effects.

Conclusion

Most common clinical manifestations were nonspecific. Cardiovocal syndrome was common in PPHN. We conclude that oral sildenafil treatment is a safe, simple and effective treatment for persistent pulmonary hypertension in newborn. Combination of bosentan with sildenafil is more effective and safe in reducing pulmonary artery (PA) pressures in high-risk patients with PPHN.

Open access
International Review of Applied Sciences and Engineering
Authors:
N. ArikaraVelan
,
V. Deepak
,
N. Dhinesh Kumar
,
G. Muthulingam
,
S. Vanitha
,
P. Karthigai Priya
, and
Sachin Sabariraj

Abstract

In this study, vermicompost is replaced for fine aggregate in geopolymer concrete (GPC). Initially mix design is made for GPC and mix proportion is proposed. The vermicompost is replaced at 5%, 10%, 15% and 20% with M sand in GPC. Result indicates the 5% replacement with vermicompost based geopolymer concrete (GPVC) has the compressive strength of 32 N mm−2 (M30 grade) whereas the compressive strength of control specimen made with GPC is 37 N mm−2. Other replacement shows 21 N mm−2, 14 N mm−2 and 11 N mm−2 respectively. The 5% replaced concrete cubes and control specimen are tested at an elevated temperature of 200°C, 400°C, 600°C and 800°C and compared with the control specimen. There is no significant difference observed in weight lost at control (GPC) and GPVC specimen. An elevated temperature, the weight loss is almost 4% at 200°C because of expulsion of water from the concrete. Afterwards only 2% weight loss is observed in remaining elevated temperature. The compressive strength loss is observed at an elevated temperature in GPC and GPVC specimen because of thermal incompatibility between aggregate and the binder. EDX results show M sand and compost contains Si, Al, C, Fe, Ca, Mg, Na and K and it is similar in the elemental composition and SEM image confirms vermicompost contains fine particles.

Open access