1,374 research outputs found

    Improving Milk Yield Performance of Crossbred Cattle in North-Eastern States of India

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    Crossbreds hold the solution to the milk-deficit problem of North-Eastern states of India. The proportion of crossbred cattle in the region is 7.54 per cent (3.46 per cent of the country) as against 13.33 per cent for the country as a whole. However, the productivity of crossbred cattle has been found considerably low (4.8 L/day) in the region as against the all-India average of 6.4 L/day of milk yield. Yield gap analysis has been applied to find out the intra-regional milk yield gaps and the factors that could be addressed in the short-run to make-up the deficit. Based on the analysis, it has been identified that the major factors affecting the milk yield of crossbred animals in the N-E states are the technological and socio-economic constraints, which could be addressed by adopting improved management practices, better feeding practices, controlling of diseases and amelioration of the socio-economic conditions of the farmers through training, education and enhancing access to the funds. Addressal of these constraints will increase actual milk yield by about 66 per cent, sufficient enough to meet the deficit of milk requirement in the region. Category-wise yield gap analysis has shown that the highest increase in milk yield will be obtained on medium category households. The factors significantly affecting the milk yield at the household level are allocation of human-days per animal, expenditure on concentrate, economic status of the farmer and availability of the green fodder in the surroundings. While no major breakthrough is expected immediately, improvement in these factors would meet the milk deficit in the region.Agricultural and Food Policy,

    Non-linear thermal post-buckling analysis of FGM Timoshenko beam under non-uniform temperature rise across thickness

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    AbstractThe present work deals with geometrically non-linear post-buckling load–deflection behavior of functionally graded material (FGM) Timoshenko beam under in-plane thermal loading. Thermal loading is applied by providing non-uniform temperature rise across the beam thickness at steady-state condition. FGM is modeled by considering continuous distribution of metal and ceramic constituents across the thickness using power law variation of volume fraction. The effect of geometric non-linearity at large post-buckled configuration is incorporated using von Kármán type non-linear strain–displacement relationship. The governing equations are obtained using the minimum potential energy principle. The system of non-linear algebraic equations is solved using Broyden’s algorithm. Four different FGMs are considered. A comparative study for post-buckling load–deflection behavior in non-dimensional form is presented for different volume fraction exponents and also for different FGMs, each for different length–thickness ratios

    Free vibration analysis of pre-stressed FGM Timoshenko beams under large transverse deflection by a variational method

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    AbstractA theoretical study on free vibration behavior of pre-stressed functionally graded material (FGM) beam is carried out. Power law variation of volume fraction along the thickness direction is considered. Geometric non-linearity is incorporated through von Kármán non-linear strain–displacement relationship. The governing equation for the static problem is obtained using minimum potential energy principle. The dynamic problem for the pre-stressed beam is formulated as an eigenvalue problem using Hamilton's principle. Three classical boundary conditions with immovable ends are considered for the present work, namely clamped–clamped, simply supported–simply supported and clamped–simply supported. Four different FGM beams, namely Stainless Steel–Silicon Nitride, Stainless Steel–Zirconia, Stainless Steel–Alumina and Titanium alloy–Zirconia, are considered for generation of results. Numerical results for non-dimensional frequency parameters of undeformed beam are presented. The results are presented in non-dimensional pressure-displacement plane for the static problem and in non-dimensional frequency-displacement plane for the dynamic problem. Comparative frequency-displacement plots are presented for different FGMs and also for different volume fraction indices

    BIOSORPTION OF CHROMIUM (VI) BY A MUTATED STRAIN OF Bacillus cereus M116

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    The removal of chromium, a highly toxic metal causing environmental pollution from dilute aqueous solution, was studied in the present work using growing and washed cells of a mutant strain of Bacillus cereus (M116) isolated from tannery waste. Particularly, the effects of pH, temperature, metal ion concentration and contact time on removal of chromium werestudied. About 40% chromium removal, was observed by growing cells of the selected strain at pH 6.5, temperature 30o±1oC, inoculum size 3%, medium volume 50 ml/250 ml Erlenmeyer flask, and initial chromium concentration 50 ppm. Usingresting cells 98.02% and 78.34% chromium removal was possible with initial chromium concentration of 25 and 50 ppm, respectively, at pH 3.0, temperature 25-35oC and 2.73 g/L biomass concentration. It was found that the overall adsorption process was best described by pseudo-second order kinetics. Freundlich and Langmuir adsorption models were found suitablefor describing the short-term biosorption of chromium (VI). IR spectral analysis of the biomass was carried out to find out the functional groups responsible for chromium (VI) biosorption

    Evaluation of the optical switching characteristics of erbium-doped fibres for the development of a fibre Bragg grating sensor interrogator

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    A polling topology that employs optical switching based on the properties of erbium-doped fibres (EDFs) is used to interrogate an array of FBGs. The properties of the EDF are investigated in its pumped and un-pumped states and the EDFs’ switching properties are evaluated by comparing them with a high performance electronically controlled MEM optical switch. Potential advantages of the proposed technique are discussed. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

    Synthesis, structure, spectral and electron-transfer properties of octahedral-[Co<SUP>III</SUP>(L)<SUB>2</SUB>]<SUP>+</SUP>/[Zn<SUP>II</SUP>(L)<SUB>2</SUB>] and square planar-[Cu<SUP>II</SUP>(L){OC(=O)CH<SUB>3</SUB>}] complexes incorporating anionic form of tridentate bis(8-quinolinyl)amine [N<SUP>1</SUP>C<SUB>9</SUB>H<SUB>6</SUB>-N<SUP>2</SUP>-C<SUB>9</SUB>H<SUB>6</SUB>N<SUP>3</SUP>, L<SUP>-</SUP>] ligand

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    The reaction of bis(8-quinolinyl)amine [N1C9H6-N2H-C9H6N3, LH] with CoII(ClO4)2 . 6H2O in methanol under aerobic conditions results in a new class of [CoIIIN6]+ (1+) chromophore incorporating an sp2-amido nitrogen center (N2) in the ligand frame. During the course of the reaction, the cobalt ion has been oxidized from its starting +2 oxidation state to +3 state in 1. The reaction of LH with the Cu-acetate yields monomeric square planar complex, [CuII(L){OC(=O)CH3}] (2). The same copper complex 2 is also obtained from Cu(ClO4) . 6H2O in presence of CH3COONa as base. On the other hand, the reaction of Zn(ClO4) . 6H2O with LH results in octahedral complex ZnII(L)2 (3). The Cu(II) complex 2 displays a four-line EPR spectrum at room temperature. Crystal structure of the free ligand (LH) shows that the amine proton [N(2)H] is hydrogen-bonded with the terminal quinoline nitrogen centers [N(1) and N(3)]. The crystal structure of 1 confirms the meridional geometry of the complex cation. The square planar geometry of copper complex 2 is confirmed by its crystal structure where the acetate function behaves as a monodentate ligand. The free ligand, LH, is found to be highly acidic in acetonitrile-water (1:1) medium and correspondingly the amine proton (NH) readily dissociates leading to its L- form even in absence of any external base. The pKb value of L- is determined to be 2.6. Both cobalt and copper complexes do not show any expected spin-allowed d-d transitions, possibly have masked by the intense charge-transfer transitions. However, in case of cobalt complex 1, one very weak unusual spin-forbidden 1A1g &#8594; 3T1g transition has been observed at 935 nm. The quasi-reversible cobalt (III)&#8596; cobalt(II) reduction of 1 is observed at E0, -1.0 V versus SCE. The reactions of bis(8-quinolinyl)amine [N1C9H6-N2H-C9H6N3, LH] with CoII(ClO4)2 . 6H2O, ZnII(ClO4)2 . 6H2O and CuII-acetate result in octahedral-[CoIII(L-)2]+ and [ZnII(L-)2] and square planar-[CuII(L-){-OC(=O)CH3}] complexes, respectively, incorporating an sp2-amido nitrogen center (N2) in the coordinated ligand frame of L. The structural, spectral and electrochemical aspects of the complexes have been described

    Agmatidine, a modified cytidine in the anticodon of archaeal tRNA\u3csup\u3eIle\u3c/sup\u3e, base pairs with adenosine but not with guanosine

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    Modification of the cytidine in the first anticodon position of the AUA decoding tRNAIle (tRNAIle 2 ) of bacteria and archaea is essential for this tRNA to read the isoleucine codon AUA and to differentiate between AUA and the methionine codon AUG. To identify the modified cytidine in archaea, we have purified this tRNA species from Haloarcula marismortui, established its codon reading properties, used liquid chromatography–mass spectrometry (LC-MS) to map RNase A and T1 digestion products onto the tRNA, and used LC-MS/MS to sequence the oligonucleotides in RNase A digests. These analyses revealed that the modification of cytidine in the anticodon of tRNAIle 2 adds 112 mass units to its molecular mass and makes the glycosidic bond unusually labile during mass spectral analyses. Accurate mass LC-MS and LC-MS/MS analysis of total nucleoside digests of the tRNAIle 2 demonstrated the absence in the modified cytidine of the C2-oxo group and its replacement by agmatine (decarboxy-arginine) through a secondary amine linkage. We propose the name agmatidine, abbreviation C+, for this modified cytidine. Agmatidine is also present in Methanococcus maripaludis tRNAIle 2 and in Sulfolobus solfataricus total tRNA, indicating its probable occurrence in the AUA decoding tRNAIle of euryarchaea and crenarchaea. The identification of agmatidine shows that bacteria and archaea have developed very similar strategies for reading the isoleucine codon AUA while discriminating against the methionine codon AUG

    Identification and codon reading properties of 5-cyanomethyl uridine, a new modified nucleoside found in the anticodon wobble position of mutant haloarchaeal isoleucine tRNAs

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    Most archaea and bacteria use a modified C in the anticodon wobble position of isoleucine tRNA to base pair with A but not with G of the mRNA. This allows the tRNA to read the isoleucine codon AUA without also reading the methionine codon AUG. To understand why a modified C, and not U or modified U, is used to base pair with A, we mutated the C34 in the anticodon of Haloarcula marismortui isoleucine tRNA (tRNA2Ile) to U, expressed the mutant tRNA in Haloferax volcanii, and purified and analyzed the tRNA. Ribosome binding experiments show that although the wild-type tRNA2Ile binds exclusively to the isoleucine codon AUA, the mutant tRNA binds not only to AUA but also to AUU, another isoleucine codon, and to AUG, a methionine codon. The G34 to U mutant in the anticodon of another H. marismortui isoleucine tRNA species showed similar codon binding properties. Binding of the mutant tRNA to AUG could lead to misreading of the AUG codon and insertion of isoleucine in place of methionine. This result would explain why most archaea and bacteria do not normally use U or a modified U in the anticodon wobble position of isoleucine tRNA for reading the codon AUA. Biochemical and mass spectrometric analyses of the mutant tRNAs have led to the discovery of a new modified nucleoside, 5-cyanomethyl U in the anticodon wobble position of the mutant tRNAs. 5-Cyanomethyl U is present in total tRNAs from euryarchaea but not in crenarchaea, eubacteria, or eukaryotes

    Identification and codon reading properties of 5-cyanomethyl uridine, a new modified nucleoside found in the anticodon wobble position of mutant haloarchaeal isoleucine tRNAs

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    Most archaea and bacteria use a modified C in the anticodon wobble position of isoleucine tRNA to base pair with A but not with G of the mRNA. This allows the tRNA to read the isoleucine codon AUA without also reading the methionine codon AUG. To understand why a modified C, and not U or modified U, is used to base pair with A, we mutated the C34 in the anticodon of Haloarcula marismortui isoleucine tRNA (tRNA2Ile) to U, expressed the mutant tRNA in Haloferax volcanii, and purified and analyzed the tRNA. Ribosome binding experiments show that although the wild-type tRNA2Ile binds exclusively to the isoleucine codon AUA, the mutant tRNA binds not only to AUA but also to AUU, another isoleucine codon, and to AUG, a methionine codon. The G34 to U mutant in the anticodon of another H. marismortui isoleucine tRNA species showed similar codon binding properties. Binding of the mutant tRNA to AUG could lead to misreading of the AUG codon and insertion of isoleucine in place of methionine. This result would explain why most archaea and bacteria do not normally use U or a modified U in the anticodon wobble position of isoleucine tRNA for reading the codon AUA. Biochemical and mass spectrometric analyses of the mutant tRNAs have led to the discovery of a new modified nucleoside, 5-cyanomethyl U in the anticodon wobble position of the mutant tRNAs. 5-Cyanomethyl U is present in total tRNAs from euryarchaea but not in crenarchaea, eubacteria, or eukaryotes.National Institutes of Health (U.S.) (GM17151)National Institutes of Health (U.S.) (GM22854)National Institutes of Health (U.S.) (ES017010)Singapore-MIT Alliance for Research and TechnologySingapore. National Research FoundationUnited States. Dept. of Energy (DE-FG36-08GO88055
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