Effect of selected pesticides on larval mortality of the neuropteran predator, Chrysopa lacciperda Kimmins, of the lac insect, Kerria lacca (Kerr)

J.P. Singh,M. Monobrullah,A.K. Jaiswal,A. Bhattacharya 한국응용곤충학회 2010 Journal of Asia-Pacific Entomology Vol.13 No.1

Laboratory bioassays were carried out to evaluate the bioefficacy of some pesticides against larval Chrysopa lacciperda Kimmins, a lac insect predator, to develop a suitable strategy for field management of this serious neuropteran pest of Indian lac insect, Kerria lacca (Kerr). Seven insecticides (lambdacyhalothrin, carbosulfan,spinosad, indoxacarb, fipronil, alphamethrin and ethofenprox) were identified based on field trials against the lac insect. They were evaluated for their bioefficacy against C. lacciperda by spraying the insect directly and by exposing the insect to a residual film. Direct spray of lambdacyhalothrin (0.005 and 0.008% a.i.), carbosulfan (0.02 and 0.03% a.i.), fipronil (0.005 and 0.01% a.i.), alphamethrin (0.005 and 0.01% a.i.), spinosad (0.02% a.i.),indoxacarb (0.02% a.i.), and ethofenprox (0.02% a.i.) exhibited 100% mortality of C. lacciperda within 24 h of treatment. Fipronil (0.005 and 0.01% a.i.) and indoxacarb (0.02% a.i.) were equally effective as 100% mortality was observed within 24 h of treatment with both modes of treatment. For most insecticides, direct spray was more effective compared to residual films. It is therefore, suggested that lambdacyhalothrin, carbosulfan,indoxacarb, spinosad, fipronil, alphamethrin and ethofenprox shall be incorporated in IPM programs for the effective management of this neuropteran predator of lac insect without adversely affecting the lac insect.

Fatigue crack effect on magnetic flux leakage for A283 grade C steel

M.I.M. Ahmad,A. Arifin,S. ABDULLAH,W.Z.W. Jusoh,S.S.K. Singh 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.6

This paper presents the characterization of fatigue crack in the A283 Grade C steel using the MMM method by identifying the effects of magnetic flux leakage towards the crack growth rate, da/dN, and crack length.The previous and current research on the relation between MMM parameters and fatigue crack effect is still unclear and requires specific analysis to validate that. This method is considered to be a passive magnetic method among other Non-Destructive Testing (NDT) methods. The tension-tension fatigue test was conducted with a testing frequency of 10 Hz with 4 kN loaded, meanwhile the MMM response signals were captured using a MMM instrument. A correlation between the crack growth rate and magnetic flux leakage produces a sigmoid shape curve with a constant values which present the gradient, m value is in the ranges of 1.4357 to 4.0506, and the y-intercept, log C in the ranges of 4×10<SUP>-7</SUP> to 0.0303. Moreover, a linear relation was obtained between the crack length and magnetic flux leakage which present the R-Squared values is at 0.830 to 0.978. Therefore, MMM method has their own capability to investigate and characterize the fatigue crack effects as a main source of fracture mechanism for ferrous-based materials.

Synthesis, magnetic and Mossbauer spectroscopic studies of Cr doped lithium ferrite nanoparticles

Srivastava, M.,Layek, S.,Singh, J.,Das, A.K.,Verma, H.C.,Ojha, A.K.,Kim, N.H.,Lee, J.H. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.591 No.-

Lithium-based ferrites are promising and potential magnetic materials for microwave applications. They possess a spinel (AB<SUB>2</SUB>O<SUB>4</SUB>) type crystal structure, where the distributions of metal cations over the tetrahedral (A) and octahedral (B) voids play a crucial role for exhibiting different physical properties. Among various parameter of synthesis, pH is an important factor that influences the cation distribution over A and B voids, overall growth of the nanoparticles and different physical properties. In the present work single phase Cr substituted lithium ferrite nanoparticles have been synthesized by the sol-gel method at different pH. The phase identification and crystallite size have been probed by X-ray diffraction studies. The crystallite size changes by 44.2-48.8nm upon varying the pH from 3.5 to 11.5. In order to investigate the cations distribution at A/B sites, Mossbauer spectroscopic measurements were done. The values of magnetic hyperfine field obtained from the Mossbauer data for the A and B sites are ~49.5T and 51T, respectively. Moreover, it is observed that the area ratio of B site to A site increases with increasing the pH. This observation further suggests that the B site is more preferable for Fe<SUP>3+</SUP> cations at higher pH than the A site. The magnetic parameter such as saturation magnetization (M<SUB>s</SUB>), remanent magnetization (M<SUB>r</SUB>), coercive field (H<SUB>C</SUB>) and squareness (S) are determined by vibrating sample magnetometer (VSM) measurements, which show a consistent increase with increasing pH. The reason for the variation in magnetic properties has been explained on the basis of increased Fe<SUP>3+</SUP> cation occupancies at the B site and size effect, which is well supported by Mossbauer spectroscopic and XRD studies.

Estimation of Suitable Methodology for Determining Weibull Parameters for the Vortex Shedding Analysis of Synovial Fluid

Singh, Nishant Kumar,Sarkar, A.,Deo, Anandita,Gautam, Kirti,Rai, S.K. The Korean Society of Medical and Biological Engin 2016 의공학회지 Vol.37 No.1

Weibull distribution with two parameters, shape (k) and scale (s) parameters are used to model the fatigue failure analysis due to periodic vortex shedding of the synovial fluid in knee joints. In order to determine the later parameter, a suitable statistical model is required for velocity distribution of synovial fluid flow. Hence, wide applicability of Weibull distribution in life testing and reliability analysis can be applied to describe the probability distribution of synovial fluid flow velocity. In this work, comparisons of three most widely used methods for estimating Weibull parameters are carried out; i.e. the least square estimation method (LSEM), maximum likelihood estimator (MLE) and the method of moment (MOM), to study fatigue failure of bone joint due to periodic vortex shedding of synovial fluid. The performances of these methods are compared through the analysis of computer generated synovial fluidflow velocity distribution in the physiological range. Significant values for the (k) and (s) parameters are obtained by comparing these methods. The criterions such as root mean square error (RMSE), coefficient of determination ($R^2$), maximum error between the cumulative distribution functions (CDFs) or Kolmogorov-Smirnov (K-S) and the chi square tests are used for the comparison of the suitability of these methods. The results show that maximum likelihood method performs well for most of the cases studied and hence recommended.

PHOTOPHYSICAL AND OPTICAL PROBE PROPERTIES OF 1-(p-N,N-DIMETHYLAMINOPHENYL)-4-PHENYL-2-METHYL-1E,3E-BUTADIENE

Singh, A.K.,Krishna, T.S.R. Korean Society of Photoscience 1997 Journal of Photosciences Vol.4 No.1

A hitherto unknown diphenylbutadiene analog viz. 1-(p-N,N-dimethylaminophenyl)-4-phenyl-2-methyl-1E,3E-butadiene (10) has been prepared and its absorption, excitation, and fluorescent emission properties in different media including various organic solvents and aqueous bovine serum albumin (BSA) have been studied. For comparision, these properties have also been investigated for the parent diphenylbutadiene (2). Diene 10 exhibits solvent polarity/polarizability-sensitive fluorescence properties ($\lambda$$_{max}$, $\Phi$$_f$, $\tau$$_f$, K$_f$, f). It also binds to the hydrophobic domains of aqueous bovine serum albumin (BSA) with a binding constant of 3.89 x 10$^4$ M$^{-1}$. The relative fluorescence quantum yield of 10 increases, while, the fluorescence lifetime decreases with increasing concentration of-BSA. The results highlight the polar character of the singlet excited state of diphenylpolyenes and the utility of 10 as fluorescence probe for studying microenvironments of organized assemblies and biological supramolecular structures.

Keratinocyte growth factor and thiazolidinediones and linolenic acid differentiate characterized mammary fat pad adipose stem cells isolated from prepubertal Korean black goat to epithelial and adipogenic lineage

Reza, A. M.,Shiwani, S.,Singh, N. K.,Lohakare, J. D.,Lee, S. J.,Jeong, D. K.,Han, J. Y.,Rengaraj, D.,Lee, B. W. Springer Science + Business Media 2014 In vitro cellular & developmental biology Animal Vol.50 No.3

The study was conducted to know and investigate the mechanism involved during mesenchymal to epithelial transition to unravel questions related to mammary gland development in prepubertal Korean black goat. We, therefore, biopsied mammary fat pad and isolated adipose cells and characterized with stemness factors (CD34, CD13, CD44, CD106, and vimentin) immunologically and through their genetic expression. Furthermore, characterized cells were differentiated to adipogenic (thiazolidinediones and alpha-linolenic acid) and epithelial (keratinocyte growth factor) lineages. Thiazolidinediones/or in combination with alpha-linolenic acid demonstrated significant upregulation of adipo-Q, PPAR-gamma, CEBP-alpha, LPL, and resistin. Adipose stem cells in induction mixture (5 mu g/ml insulin, 1 mu g/ml hydrocortisone, and 10 ng/ml epidermal growth factor) and subsequent treatment with 10 ng/ml keratinocyte growth factor revealed their trans-differentiating ability to epithelial lineage. From 2 d onwards, the cells under keratinocyte growth factor influenced cells to assume rectangular (2-4 d) to cuboidal (8-10 d) shapes. Ayoub-Shklar stain developed brownish-red pigment in the transformed cells. Though, expressions of K8 and K18 were noted to be highly significant (p < 0.01) but expressions of epithelial membrane antigens and epithelial specific antigens were also significant (p < 0.05) compared to 0 d. Conclusively, epithelial transformations of mammary adipose stem cells would add up knowledge to develop therapeutic regimen to deal with mammary tissue injury and diseases.

Observation ofX(3872)inB→X(3872)Kπdecays

Bala, A.,Bhardwaj, V.,Trabelsi, K.,Singh, J. B.,Abdesselam, A.,Adachi, I.,Aihara, H.,Arinstein, K.,Asner, D. M.,Aulchenko, V.,Aushev, T.,Ayad, R.,Aziz, T.,Bahinipati, S.,Bakich, A. M.,Bansal, V.,Barbe American Physical Society 2015 PHYSICAL REVIEW D - Vol.91 No.5

Development of Nanoparticle-Based High Current Density Cathode for THz Devices Application

Barik, R. K.,Singh, A. K.,Shukla, S.,Singh, T. P.,Raju, R. S.,Park, G.-S Institute of Electrical and Electronics Engineers 2016 IEEE transactions on electron devices Vol.63 No.4

<P>Scandia (Sc2O3)-doped tungsten nanoparticle-based high current density cathode is developed for the application in terahertz (THz) devices. This paper involves synthesis of scandia-doped tungsten nanoparticle powder using chemical technique, estimation of optimum porosity, and development of pellet with required porosity by optimizing process parameters. The cathode, made out of the above pellet, is tested in an analytical system containing Auger electron spectroscope and anode. The results show that the cathode can deliver more than 100 A/cm(2) current density with stable emission-strongly recommending it as a candidate for the use in a THz device. Theoretical estimates show that the void porosity is to be kept at 21% for proper surface coverage to produce good emission with long life.</P>

Influence of Level of Feed Intake on Concentration of Purine Derivatives in Urinary Spot Samples and Microbial Nitrogen Supply in Crossbred Bulls

George, S.K.,Dipu, M.T.,Mehra, U.R.,Verma, A.K.,Singh, P. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.9

The potential of the spot urine sampling technique as an alternative to performing a total urine collection to predict the microbial nitrogen supply was evaluated in crossbred bulls. In a completely randomized design, 20 growing crossbred bulls were assigned four levels of feed intake (120, 100, 80 and 60% of voluntary dry matter intake) on diets comprised of wheat straw and concentrate mixture (50:50). After three months of experimental feeding, a metabolism trial was conducted for ten days, during which spot urine collections were performed every 6 h post feeding on days 9 and 10. The daily urinary excretion of allantoin (A) and purine derivatives (PD) decreased with the reduction in feed intake while creatinine (C) excretion remained similar in animals fed at different levels. The microbial nitrogen (MN) supply calculated from the PD excreted in total urine (35.08 to 72.08 g/d) was higher at increased levels of feed intake. PD concentration in spot urine samples had poor correlation with feed intake except at 12 h post feeding. A/C ratio and PD/C ratio in spot urine samples remained similar irrespective of sampling time and significantly (p<0.01) correlated with daily urinary PD excretion, digestible organic matter intake and dry matter (DM) intake. However, no significant differences were evident in these ratios among animals fed at levels 120, 100 and 80% of voluntary dry matter intake (VDMI) at different times post feeding. These results suggests that the spot urine sampling technique to predict the microbial protein supply is not suitable for detecting small differences in MN supply and hence, estimation of PD excreted in total urine (mmol/d) is necessary to assess precisely the MN supply in crossbred bulls.

Effect of proton irradiation on electrical properties of a-As₂S₃

Gautam, S.,Thakur, A.,Shukla, D.K.,Shin, H.J.,Chae, K.H.,Singh, K.P.,Goyal, N. North-Holland 2011 Journal of non-crystalline solids Vol.357 No.11

This paper reports the effect of proton irradiation on the electrical properties of a-As<SUB>2</SUB>S<SUB>3</SUB> in the temperature range of 323-418K and frequency range 0.1-100kHz. The variation of transport property is studied with proton irradiation dose (1x10<SUP>13</SUP>ions/cm<SUP>2</SUP> and 1x10<SUP>15</SUP>ions/cm<SUP>2</SUP>). It has been observed that proton irradiation changes the dc conductivity (σ<SUB>dc</SUB>), dc activation energy (ΔE<SUB>dc</SUB>) and ac conductivity (σ<SUB>ac</SUB>(ω)). The σ<SUB>dc</SUB> and σ<SUB>ac</SUB>(ω) increases with dose of proton irradiation. The value of frequency exponent (s) decreases with the temperature and irradiation dose. These results are explained in terms of change in density of defect states in these glasses.