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91.
To address people's concerns of exogenous oxytocin (OT) administration to lactating bovines, a study was undertaken to (a) establish an enzyme immunoassay (EIA) for OT determination in milk, (b) quantify OT in milk of cows administered OT, and (c) study influence of pasteurization on OT stability in milk. A sensitive EIA validated according to the criteria of European Union—Decision 2002/657/EC was developed for OT in skim milk in an analytical range of 10-250 pg mL−1 with a decision limit (CCα) of 30 pg mL−1 and detection capability (CCβ) of 41.5 pg mL−1. Milk samples collected from cows (n = 38) administered either 25 or 50 IU OT prior to milking were investigated for the presence of OT. There was no significant difference among both groups with the mean concentrations of OT being 15.8 and 14.9 pg mL−1 for cows subjected to 25 and 50 IU OT administration, respectively. The OT levels in skim milk of control cows (n = 30; untreated) were basal (around 10 pg mL−1). All the analyzed milk samples were below the CCα value of 30 pg mL−1. Pasteurization of OT spiked milk samples at different temperature and sample holding conditions reduced the immunological activity of OT to 43% at 110 °C. However, no further decline occurred in the immunological activity with increased pasteurization temperature and time. It was concluded that the milk OT concentrations after OT administrations were minimal and below the assay decision limit. However, OT was quite stable to pasteurization in OT spiked milk. 相似文献
92.
Sodium cleaves elemental tellurium, TeX, quantitatively to Te2– 2 and Te2- in anhydrous tetrahydrofuran in the presence of catalytic amounts of naphthalene. Subsequent addition of alkylating agent affords dialkyl tellurides and dialkyl ditellurides in excellent yields. 相似文献
93.
T. Vijay T. Narasimhamurthy H. S. Yathirajan R. S. Rathore P. Nagaraja 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(1):o36-o38
In the crystal structure of the title salt, C7H7Cl2N2O2+·Cl−, the chloride anions participate in extensive hydrogen bonding with the aminium cations and indirectly link the molecules through multiple N+—H⋯Cl− salt bridges. There are two independent molecules in the asymmetric unit, related by a pseudo‐inversion center. The direct intermolecular coupling is established by C—H⋯O, C—H⋯Cl and C—Cl⋯Cl− interactions. A rare three‐center (donor bifurcated) C—H⋯(O,O) hydrogen bond is observed between the methylene and nitro groups, with a side‐on intramolecular component of closed‐ring type and a head‐on intermolecular component. 相似文献
94.
We explore the phases of
supersymmetric U(N) gauge theories with fundamental matter that arise as deformations of
SQCD by the addition of a superpotential for the adjoint chiral multiplet. As the parameters in the superpotential are varied, the vacua of this theory sweep out various branches, which in some cases have multiple semiclassical limits. In such limits, we recover the vacua of various product gauge group theories, with flavors charged under some group factors. We describe in detail the structure of the vacua in both classical and quantum regimes, and develop general techniques such as an addition and a multiplication map which relate vacua of different gauge theories. We also consider possible indices characterizing different branches and potential relationships with matrix models. 相似文献
95.
Synthesis of Novel Benzofuran‐Gathered C‐2,4,6‐substituted Pyrimidine Derivatives Conjugated by Sulfonyl Chlorides: Orally Bioavailable,Selective, Effective Antioxidants and Antimicrobials Drug Candidates 下载免费PDF全文
Javarappa Rangaswamy Honnaiah Vijay Kumar Salakatte Thammaiah Harini Nagaraja Naik 《Journal of heterocyclic chemistry》2015,52(5):1349-1360
In the present study, we have made an effort to develop the novel synthetic antioxidants and antimicrobials with improved potency. The novel benzofuran‐gathered C‐2,4,6‐substituted pyrimidine derivatives 5a , 5b , 5c , 5d , 5e , 5f , 6a , 6b , 6c , 6d , 6e , 6f , 7a , 7b , 7c , 7d , 7e , 7f , 8a , 8b , 8c , 8d , 8e , 8f , 9a , 9b , 9c , 9d , 9e , 9f were synthesized by simple and efficient four‐step reaction pathway. Initially, o‐alkyl derivative of salicylaldehyde readily furnish corresponding 2‐acetyl benzofuran 2 in good yield, upon the treatment with potassium tertiary butoxide in the presence of molecular sieves. Further, Claisen–Schmidt condensation with aromatic aldehydes via treatment with thiourea followed by coupling reaction with different sulfonyl chlorides afforded target compounds. The structures of newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR, mass, and elemental analysis and further screened for their antioxidant and antimicrobial activities. The results showed that the synthesized compounds 8b , 8e , 9b , and 9e produced significant antioxidant activity with 50% inhibitory concentration higher than that of reference, whereas compounds 7d and 7c produced dominant antimicrobial activity at concentrations 1.0 and 0.5 mg/mL compared with standard Gentamicin and Nystatin, respectively. 相似文献
96.
97.
Vijay Singh 《Tetrahedron letters》2006,47(39):7043-7045
Tributyltin hydride-mediated straightforward synthesis of a new isoxazolo-benzazulene system from the derivatives afforded by the Baylis-Hillman reaction of 3-(2-bromophenyl)-4-isoxazolecarbaldehydes is described. 相似文献
98.
[reaction: see text] The 1,4-dipole derived from isoquinoline and DMAD has been shown to react readily with N-tosylimines resulting in the diastereoselective synthesis of 2H-pyrimido[2,1-a]isoquinoline derivatives. 相似文献
99.
An investigation of the properties of poly(dimethylsiloxane)-bioinspired silica hybrids 总被引:1,自引:0,他引:1
Siddharth V. Patwardhan Vijay P. Taori Nikhil R. Agashe Gregory Beaucage Stephen J. Clarson 《European Polymer Journal》2006,42(1):167-178
Elastomers typically require the incorporation of reinforcing fillers in order to improve their mechanical properties. For commercial silicone systems silica and titania are typically used as fillers. Fumed and precipitated silica are made on an industrial scale for many applications; however, we have shown recently that biological and synthetic macromolecules can generate new silica structures using a bioinspired route. Herein we have incorporated bioinspired silica fillers into poly(dimethylsiloxane) (PDMS) elastomers and investigated their mechanical, morphological and thermal properties as a function of filler loading. The equilibrium stress-strain characteristics of the PDMS-bioinspired silica hybrids were determined as a function of bioinspired filler loading and the Mooney-Rivlin constants (2C1 and 2C2) were calculated. The thermal characteristics, in particular glass transition temperatures (Tg) and melting points (Tm), of the PDMS-bioinspired silica hybrids were characterized using differential scanning calorimetry (DSC). The thermal stability of these hybrid materials were investigated using thermogravimetric analysis (TGA). The morphology of the samples was characterized using scanning electron microscopy (SEM), and the filler dispersion was characterized using ultra small angle X-ray scattering (USAXS) and scanning electron microscopy (SEM). Although spherical silica particles were used here, we have demonstrated elsewhere that this bioinspired synthetic route also enables highly asymmetric silica structures to be prepared such as fibres and sheets. This methodology therefore offers the interesting possibility of preparing new hybrid systems where the properties are highly anisotropic. 相似文献
100.
Kamlendra Awasthi Vaibhav Kulshrestha D.K. Avasthi Y.K. Vijay 《Radiation measurements》2010,45(7):850-855
Membranes of polyethylene terephthalate, irradiated by O6+ ions at various fluences were characterized by UV/VIS, FTIR, Micro-Raman spectroscopy’s, X-ray diffraction and Atomic force microscopy. UV/VIS measurements indicate shifting of the absorption edge from ultraviolet towards visible regions indicating carbonization while FTIR measurement shows the material degradation. The intensities of Raman band of ion irradiated polymer increases with the ion fluence. XRD results show decrease and shift in main peak of irradiated PET. Surface roughness is found to decrease with increasing ion fluence. 相似文献