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Piezoelectric materials can develop mechanical strain upon applying electric voltage and vice-versa. A piezoelectric bimorph, widely used in various sensors and actuator applications, essentially behaves like a beam and consists of a nonpiezoelectric material substrate layer glued between two piezoelectric layers. The application of an electric field alone can induce the bending of such a beam. Studies on the modeling of the piezoelectric bimorph are mostly restricted to the small deflection regime. In the present work, a simple numerical method is proposed to obtain the large deflection response of any piezoelectric bimorph. To begin with, the governing equation of a cantilever bimorph under electric field and end load is obtained. The nonlinear governing equation is then linearized with respect to the current time step. Subsequently, the linearized equation is solved using the RK4 method. From the numerical results, it is found that the response of the key design parameter, namely free displacement is considerably different from that predicted from small deflection analysis. Also, as the entities involved are suitably nondimensionalized, the results are directly relatable to all classes of piezoelectric materials. The nondimensionalization has also paved the way for better insight into the physical problem by rendering a simple mathematical representation. [ABSTRACT FROM AUTHOR]

In cyclic bending processes where plastic deformation occurs, residual stresses develop along a beam cross-section. A residual stress profile governs the load-carrying capacity and the shape of the beam. In the present study, residual stress profiles for solid and hollow beam cross-sections of square and circular shapes are studied. The scope of the present study is limited to the Euler-Bernoulli beam with small strain, elastic perfectly plastic material model without the Bauschinger effect under quasi-static loading. A layered approach is utilized to obtain the moment-curvature (M- κ ) response diagram. The induced residual stress profiles of solid and hollow cross-sections possessing equal net-bending resisting areas are compared. It is found that hollow sections are better in carrying moment as compared to their solid section counterparts. However, hollow sections are more prone to plasticity-induced damage and local buckling compared to solid sections. These two phenomena are adequately addressed in the article. The relevant variables of the governing equation are properly normalized to aid in developing deeper dimensionless insight into the elasto-plastic bending problems. The appropriate normalization and consideration of the limitations of the hollow section in elasto-plastic bending are expected to help a design engineer choose the right section for her/his applications. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the effect of supersubstorm of September 7 and 8, occurred during magnetic storm of September 7–8, 2017 on horizontal component of geomagnetic field (H) upon the high latitude (ABK, FCC, MGD and UPS), middle latitude (ABG, BOU, DUR and PHU) and low latitude (API, GUA, KOU, and MBO) stations. From these different stations, complexities in the characteristics of H component were identified, showing diverse effects during the supersubstorm. To characterize the common features associated with various intrinsic processes for transfer of energy during the event, the continuous wavelet technique (CWT) and cross correlation analysis are used. The CWT identified a significant energy pattern in the signal of high spectral variability from time scale 1 to 2 minutes during 24 and 37 hours. The cross correlation analysis suggests that the perturbation in H component at all latitude strongly correlates with FAC, PCV, TE, AP, JH and RC respectively. This study helps to understand energy dynamics, potential and current within the magnetosphere, in the form of FAC, PCV, RC, JH, AP and TE during SSSs. [ABSTRACT FROM AUTHOR]

In this article, we analyze vertical total electron content (VTEC) over Nepal for 4 periods: March 14–25, 2015, June 18–29, 2015, May 24–June 4, 2017, and September 3–14, 2017. In each period, there are quiet geomagnetic days and intense geomagnetic stormy days. The VTEC observed during these periods has observed both positive and negative ionospheric storms. We compared VTEC Receiver-Independent Exchange Format (RINEX) observations with the Global Ionospheric Map (GIM), Centre for Orbit Determination in Europe (CODE), and IGS working group (IGSG). We found in RINEX observation of the VTEC a noon bite out profile with predominance of morning and afternoon peaks and a nighttime peak, but this was not noticeable clearly with CODE and IGSG models. The comparison between RINEX TEC, CODE, and IGSG models shows that the GIM model does not estimate RINEX VTEC over Nepal. The disagreement between VTEC CODE/IGSG and VTEC RINEX is important during geomagnetically quiet periods, while there is good agreement between VTEC CODE/IGSG and VTEC RINEX during strong geomagnetic storms. We also find a greater disagreement between the models and the data at the equinoxes when the VTEC is larger. It is, therefore, necessary to introduce data from Nepal stations into the models CODE and IGSG in order to improve them. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the performance of the NeQuick 2 (NeQ-2) model with respect to Ciraolo's and Gopi's derived ionospheric vertical Total Electron Content (vTEC) during the years 2014 and 2015. GPS observables derived from dual-frequency receivers over western Nepal (Simikot, Bhimchula, and Nepalganj) are processed to obtain the experimental vTEC utilizing Gopi's and Ciraolo's calibration procedures. The monthly and seasonal behavior of vTEC obtained from each calibration technique is compared with the vTEC obtained from the NeQ-2 model during a quiet period. It is observed that the vTEC value obtained from all studied approaches started to increase from 00:00 Universal Time (UT = Local Time(LT) +5:45), reached a maximum around 08:00 UT (13:45 LT), followed by a decrease, attaining a minimum value around 23:00 UT (4:45 LT). Moreover, a comparative study showed that vTEC computed using the Ciraolo calibration technique overestimates GPS vTEC, calculated in all hours and months by Gopi's approach. In the Spring and Summer, vTEC derived using Ciraolo's TEC calibration overestimates NeQ-2 and underestimates it in the Autumn and Winter. It is found that NeQ-2 model vTEC is favorably associated with GPS vTEC obtained using the Gopi procedure in Spring and correlates with the Ciraolo technique in Autumn. Two GPS vTEC estimations demonstrate superior consistency in the Summer and Winter seasons over the region of Nepal. It is found that the mean absolute difference between NeQ-2 prediction and GPS vTEC procured through the Gopi approach is less on the storm event day. By contrast, it is discovered less by the Ciraolo technique when the storm is recovering (except for a few cases). [ABSTRACT FROM AUTHOR]

The Palaeoproterozoic eastern Mahakoshal belt of Central India Tectonic Zone (CITZ) is known for gold occurrences. Gold occurs predominantly in quartz veins and quartz-carbonate veins. It is associated with pyrite, pyrrhotite and arsenopyrite mineral assemblages. The secondary alteration products such as 'scorodite' and 'mansfieldite' are also associated with gold mineralisation. Recent investigations carried out in Parsoi area, have indicated the association of gold with bismuth, bismuthinite and telluride. This is the first record of bismuth from the Mahakoshal belt. The studies of the bismuth tellurides contribute to the assessment and evaluation of concentrations of gold resources. [ABSTRACT FROM AUTHOR]

A deep learning network is introduced to predict concentrations of gases in the underground coal mine enclosed region using various IoT-enabled gas sensors installed in a metallic gas chamber. The air is sucked automatically at specific intervals from the sealed-off site utilizing a solenoid valve, suction pump, and programmed microprocessor. The gas sensors monitor the gas content in the underground coal mine and communicate gas concentration to the surface server room through a wireless network and cloud storage media. The t-SNE_VAE_bi-LSTM model is proposed in this study as a prediction model that combines the t-SNE, VAE, and bi-LSTM networks. The proposed model's t-SNE method aims to minimize the dimensionality of the recorded gas concentration; and VAE layer intends to retrieve the inner characteristics of low-dimensional gas concentration. Finally, the given model's Bi-LSTM layer tries to forecast the concentrations of CH4, CO2, CO, O2, and H2 gases. The proposed model's prediction accuracy is compared with the existing two models, namely auto-regressive integrated average moving (ARIMA) and chaos time series (CHAOS). The experiment findings demonstrate that the t-SNE_VAE_bi-LSTM model forecasted mean square error (MSE) is more accurate, and it has lesser MSE value of 0.029 and 0.069 for CH4; 0.037 and 0.019 for CO2; 0.092 and 0.92 for CO; 1.881 and 1.892 for O2; and 1.235 and 1.200 for H2 than the ARIMA and CHAOS models, respectively. [ABSTRACT FROM AUTHOR]

Tricyclazole, a systemic fungicide is recommended to treat of diseases in irrigated rice. Channa punctatus (Bloch) is a freshwater fish also found in paddy fields. This maiden study was designed to evaluate acute toxicity of tricyclazole and its responses of certain biomarker enzymes in Channa punctatus. By regression analysis method, 24, 48, 72 and 96hr-LC50 dose of tricyclazole was calculated 54.30, 36.76, 32.63 and 25.06 mg l-1 respectively. The range of LC50 dose indicates highly toxic nature of tricyclaozole. Fish were then exposed to 0.25 and 1.25 mg l-1 sublethal dose of tricyclazole for short term (24, 48 and 96 hours) and long term (15, 30 and 45 days) exposure and the alterations of enzyme activities were determined. Alkaline phosphatase activities exposed to 0.25 mg l-1 were increased insignificantly (p>0.05) after 24 hours but increased significantly (p<0.05) to 0.25 and 1.25 mg l-1 tricyclazole at all other treatments. Alanine transaminase and aspartate transaminase increased significantly (p<0.05) in response to tricyclazole during both exposures. These findings may be used in the assessment of the potential risk of tricyclazole on food chain and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

The impact of long term sub-lethal exposure to lead on biomarkers of blood was studied in Channa punctatus. A dose of 9.991 and 49.955 µmol L-1 was found to modify plasma electrolytes, hematological and biochemical parameters. Significant reductions in plasma calcium, plasma phosphate, total erythrocyte count, hemoglobin, packed cell volume and serum protein were observed in treated fish in comparison to control fish. Conversely, total leucocyte count and serum glucose showed significant elevation in test fish. The decrease of serum cholesterol and increase of serum urea was found significant only in higher dose of lead. The results demonstrated the novel finding of lead on plasma electrolytes in this fish. The probable reasons for these changes have been discussed. The information may be useful in field monitoring for paddy-cum-fish culture. [ABSTRACT FROM AUTHOR]

Elastica problems with non-conservative moving forces are more complicated as compared to end loaded elastica problems. Established methods exist to solve an end loaded elastica problem. For solving a moving boundary problem, such methods need considerable modification or re-formulation. In this article, results of an end loaded elastica problem which is readily obtainable are used to solve two relatively involved moving boundary cases. The solution methodology involves a unique normalization procedure for the available elastic solution followed by few simple steps. One of the problems considered is three point bending of elastica with finite roller dimension. The other one being cantilever elastica under the action of wedge contact. Structural stiffening is observed in both the cases as a result of moving boundary condition as compared to when roller dimension is negligible or wedge makes only point contact. A structured approach may potentially originate from this kind of procedure to tackle more complicated moving boundary problems of elastica. [ABSTRACT FROM AUTHOR]

A cross sectional study was made to establish an Impact of Age on Blood Pressure from 2328 students (950 female and 1378 male students) of Department of different disciplines of Veer Kunwar Singh University, Arrah-802 301 between age group of 20-29 years from July 2011 to May 2013. Their systolic pressure as a whole ranged from 119.40±12.06 to 126.97±15.61mmHg while, the diastolic pressure increased from 77.9+9.96 to 82.3+6.64mmHg. The relationship between age and systolic as well as diastolic pressure was found highly significant (r=0.9938,p<0.001andr=0.9362,p<0.001). On the gender basis out of 2328 students, systolic pressure of 950 female students ranged from 117.98± 9.22 to 123.62±14.58 mm Hg and their diastolic pressure increased from 77.64+4.19 to 80.8+3.96 mmHg. The age and systolic as well as diastolic pressure showed a positive correlation (r=0.9919, p<0.001; r=0.9800, p< 0.05). On the other hand, the systolic pressure of 1378 male students ranged from 120.83+14.90 to 130.33+16.65 mmHg and the diastolic pressure from 78.16+15.73 to 84.2±9.2 mmHg. Ahigh correlation (r=0.9830,p<0.001 and r= 0.8690, p<0.01) was shown by these two variables. The probable reasons for the difference in systolic and diastolic pressure as well as difference in blood pressure of female and male students are also discussed. [ABSTRACT FROM AUTHOR]

Background: Behaviours adopted during adolescence affect the reproductive health in the long run. Objectives: 1.To study the socio-demographic characteristics of adolescent girls.2.To study knowledge, attitude and behaviour of adolescent girls with reference to reproductive health issues .3.To explore the reproductive health needs of adolescent girls. Materials and Method: A list of all adolescent girls was obtained from ICDS project catering to the study area. Total 200 adolescent girls in the age group of 15-19 years were interviewed by systematic random sampling, maintaining full privacy, with prior consent using a pretested questionnaire containing structured, pre-coded and few open ended questions. The data was analyzed by using percentages and chi-square test. Results: Only 28.14% females had a prior knowledge of menstruation. About 11.5% mentioned that females determine the sex of the child. Less than half, 49.5% were aware about any family planning method. More than 3/4th adolescent girls interviewed knew about the principle modes of transmission of AIDS. Only 38.5% females were aware of the potential benefit of condom use in preventing HIV transmission.92% expressed the need to have detail information on conception and family planning. Interpretation and conclusions: A significant number of girls were unaware about the various reproductive health issues, ranging from menstruation, conception, contraception to STI'S and HIV-AIDS. Significant association was seen between their level of education and knowledge on HIV-AIDS and Myths about HIV. [ABSTRACT FROM AUTHOR]

Background:Indian children and adolescents have higher body fat percentage at a given body mass index than their Western counterparts.Objective:To create gender-specific percentile curves for total body fat percentage (TBFP), total body fat mass (TBFM), fat mass index (FMI) and android:gynoid (A:G) ratio for screening adiposity in healthy Indian children.Methods:Data on body composition by dual-energy X-ray absorptiometry were obtained from a cross-sectional study conducted from May 2006-July 2010 on 888 (462 boys) apparently healthy children from affluent area schools and colleges in Pune city, India. Reference percentile curves were derived for boys and girls for TBFP, TBFM, FMI and A:G ratio. These percentile curves were validated using data on metabolic syndrome risk components in separate sample of 332 (148 boys) children.Results:The median TBFP increased little (4%) from 5 to 18 years of age in boys compared with that in girls (19%). TBFP percentiles showed plateau after 13 years of age in boys, whereas a steady increase was seen till 18 years in girls. The median TBFM increased less (7 kg) from 5 to 18 years in boys compared with that in girls (13.4 kg). The curve for median FMI in boys was relatively flat with FMI remaining near 3 kg m−2 after 13 years of age, whereas in girls median FMI increased with age till about 15 years of age. A:G ratio curves increased with age in both boys and girls up to 18 years of age. In a separate sample of 332 children, according to percentiles developed in the current study, children with TBFP/TBFM/FMI percentiles between 85th and 95th or >95th percentile had significantly higher metabolic risk parameters as compared with those with <85th percentile (P<0.05).Conclusions:Percentile curves developed in the current study would be useful in assessment of adiposity and thus cardiometabolic risk in Indian children. [ABSTRACT FROM AUTHOR]

X In the modern era due to the growing industrialization mankind is compelled to face to problems arising from pollution & stress. Bronchial asthma is one of the diseases in which these factors play important role. In the present day no treatment for asthma is complete. In this study the possible role of yoga therapy as an adjunct to the conventional drug therapy was evaluated. A group of thirty male patients of bronchial asthma in the age group of thirty to forty years was selected from OPD of yoga therapy centre. The height, weight & severity of the disease were comparable. The pulmonary function tests selected were FVC, FEV1, FEV1/FVC%, PEFR & MVV. The instrument used was medispiror i.e. computerised spirometer. The results of pulmonary function tests before & after three months of yoga therapy were compared but the improvement was not statistically significant (p value > 0.005).The results of pulmonary function tests before & after six months of yoga therapy were compared & it was statistically significant improvement. [For FVC (p value < 0.01) & for FEV1, FEV1/FVC %, PEFR & MVV (p value < 0.001)] It was concluded from the study that the yoga therapy is beneficial in long term & can be suggested as an adjunct to the conventional drug therapy. [ABSTRACT FROM AUTHOR]

Objective:To evaluate the continuous metabolic syndrome score (cMetS) in Indian children and to investigate its relationship with the risk of carotid arterial stiffness.Methods:Data on weight, height, mean arterial pressure, serum lipids, insulin, glucose, carotid intima-media thickness and stiffness parameters, that is, pulse wave velocity (PWV), elasticity modulus (Ep), stiffness index (β) and arterial compliance (AC), were assessed in 236 children (6-17 years) from Pune city, India. cMetS was computed using standardized Z-scores for metabolic syndrome (MS) components. cMetS cutoff was obtained by receiver operating characteristic curve analysis across MS components.Results:cMetS was lowest (−3.6±2.0) in normal children and highest (3.3±2.4) in MS children. cMetS increased progressively with number of risk components. The cutoff of cMetS yielding maximal sensitivity (80%) and specificity (94%) for predicting the presence of MS was −0.8 (area under the curve=0.921 (95% CI: 0.877-0.964)). In children with cMetS above −0.8, average PWV (4.3±0.6 m s−1), β (3.8±1.2) and Ep (50.4±14.5 kPa) were significantly higher than the respective values (3.7±0.5 m s−1; 3.4±0.8; 37.0±10.0 kPa) in children with cMetS below −0.8, whereas AC was lower (1.2±0.5 mm2 kPa−1) in children with cMetS above −0.8 as against AC (1.4±0.3 mm2 kPa−1) in children with cMetS below −0.8 (P<0.05), demonstrating the risk of stiffness with increasing score. Pearson's correlation coefficients of cMetS with PWV (r=0.575), β (r=0.347), AC (r=−0.267) and Ep (r=0.530) were statistically significant (P<0.01).Conclusion:Results demonstrate the usefulness of cMetS over individual MS components as a better tool for assessment of atherosclerotic risk in children. [ABSTRACT FROM AUTHOR]

Accurate modeling of thermal power plant is very useful as well as difficult. Conventional simulation programs based on heat and mass balances represent plant processes with mathematical equations. These are good for understanding the processes but usually complicated and at times limited with large number of parameters needed. On the other hand, artificial neural network (ANN) models could be developed using real plant data, which are already measured and stored. These models are fast in response and easy to be updated with new plant data. Usually, in ANN modeling, energy systems can also be simulated with fewer numbers of parameters compared to mathematical ones. Step-by-step method of the ANN model development of a coal-fired power plant for its base line operation is discussed in this paper. The ultimate objective of the work was to predict power output from a coal-fired plant by using the least number of controllable parameters as inputs. The paper describes two ANN models, one for boiler and one for turbine, which are eventually integrated into a single ANN model representing the real power plant. The two models are connected through main steam properties, which are the predicted parameters from boiler ANN model. Detailed procedure of ANN model development has been discussed along with the expected prediction accuracies and validation of models with real plant data. The interpolation and extrapolation capability of ANN models for the plant has also been studied, and observed results are reported. [ABSTRACT FROM AUTHOR]

Spot blotch is an important disease of wheat (Triticum aestivum L.) in South Asia. Division of test sites for this disease into homogenous subregions is expected to contribute to more efficient evaluation and better differentiation of cultivars. Data from a collaborative regional program of South Asia conducted by CIMMYT were analyzed to group testing sites into relatively homogenous subregions for spot blotch area under the disease progress curve (AUDPC). Five-year data of eight locations from Eastern Gangetic Plains Nursery (EGPSN) and five locations of the Eastern Gangetic Plains Yield Trial (EGPYT) conducted in three countries (India, Nepal, and Bangladesh) of South Asia were used. A hierarchical cluster analysis was used to group locations on the basis of genotype × location interaction effects for spot blotch AUDPC. Cluster analysis divided South Asia into two broad regions and four subregions. This classification was not entirely consistent with the geographic distribution of locations, but clusters mostly followed general geographic-climatic locations. The locations Varanasi (India) and Bhairahawa (Nepal) were identified as the most suitable sites for evaluation of spot blotch, followed by Rampur (Nepal). The major determinant for the clustering was mean temperature. The results suggest that the major wheat region of South Asia can be divided into subregions, which may reduce the cost of resistance evaluation and aid in developing wheat with resistance to this disease. [ABSTRACT FROM AUTHOR]

Aim : To document the clinical, histological, immunohistochemical and ultrastructural features of three malignant melanomas showing neuroendocrine differentiation. Methods and results : Three patients, two with primary cutaneous melanoma and one with nasal mucosal melanoma, subsequently developing or simultaneously presenting with metastatic malignant melanoma, were studied by conventional histological technique, immunohistochemistry of formalin-fixed paraffin-wax embedded tissues, and electron microscopy of epoxy-resin-embedded tumour tissue. Tumours showed either small cell or conventional malignant melanoma cell morphology. One of the three primary melanocytic lesions (the nasal melanoma) exhibited neuroendocrine differentiation immunohistochemically. All three metastatic malignant melanomas showed, in varying combinations, immunohistochemical and ultrastructural evidence for neuroendocrine differentiation: they were positive for the melanocytic markers, S100 protein, HMB-45, Melan-A and tyrosinase, and the neuroendocrine markers chromogranin, synaptophysin and neurofilament protein. Ultrastructural study in two of the metastases revealed neuroendocrine granules but no lattice-bearing melanosomes. Conclusions : The cases described are the most comprehensively investigated malignant melanomas showing neuroendocrine differentiation to date, and the first to document neuroendocrine differentiation ultrastructurally in these tumours. Malignant melanoma with neuroendocrine differentiation therefore needs to be recognized among the other, better known variants of malignant melanoma. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Critical care as part of respiratory training in the UK" which is published in the previous issue of the periodical.

A letter to the editor is presented about bronchial biopsies and the immunology-based stains techniques including the heamatoxylin and eosin stain.