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71.
Seed oil ofSemecarpus kurzii was found to contain 10.5% of 9-hydroxy-cis-12-enoic (isoricinoleic) acid along with the usual fatty acids. The identification of the hydroxy acid was made on the basis of chromatographic, spectroscopic and chemical methods, with isoricinoleic acid used as the reference standard.  相似文献   
72.
The failure analysis of an air crash conclusively shows that the cage of the central main bearing of the compressor region failed due to fatigue. The broken piece of the cage got struck between the bearing balls and the races and impaired the function of the bearing resulting in the crash.  相似文献   
73.
Synthetic peptide antigens representing the repeat sequences of malarial antigens showed poor immunogenicity and protection in clinical trials. In the present study, RESA, an asexual blood stage antigen, containing (EENVEHDA)2 and (DDEHVEEPTVA)2 sequences were chemically linked to a promiscous T-cell determinant (CS.T3) of the circumsporozoite protein of P. falciparum. The synthetic constructs either alone or coentrapped with immunoadjuvants (nor muramyl dipeptide/lauroyl tetrapeptide) were administered in liposomes to mice of varying genetic background and the immunogenicity of different formulations were compared under identical experimental conditions. The RESA peptide formulations containing the T-cell determinant and the adjuvants generated high titre and affinity antibodies in all the strains, as compared to peptide(s) alone. The booster immunization induced a strong anamnestic response in each group. Though the major IgG isotype is of IgG1 and IgG2b interestingly, formulations containing CS.T3 have a higher proportion of cytophilic IgG2b isotype. There was a significant fall in the levels of IgG2b isotype while IgG1 levels were maintained same in the third bleed (day 60, without booster immunization). The mixed peptide group preparation containing the adjuvant is found to be a better immunogen than that of respective peptides itself. The in vitro merozoite reinvasion inhibition assay showed 76-96% inhibition with the formulations containing RESA peptide(s)-CS.T3 and the adjuvant, while with peptides alone the inhibition was 50-56%. This study highlights the importance of an alternative approach for developing peptide based immunogen against malaria.  相似文献   
74.
The seed oils of Acacia mollissima, A. torta, A. lenticularis and A. nilotica are found to contain 6.2, 5.3, 4.7 and 3.1%, respectively, cor-onaric acid in addition to other fatty acids. The structure of coronaric acid was established by chemical and physical methods using Chrysanthemum coronarium seed oil and its derived coronaric acid as the reference sample.  相似文献   
75.
Owing to the superior properties, of stainless steel it is pertinent to make use of it in various automotive, aerospace, nuclear, chemical and cryogenic applications. It is observed that a wide range of dissimilar materials can be easily integrated by solid phase bonding techniques, such as friction welding and explosive bonding. This study mainly focuses on friction welding of AISI 304 austenitic stainless steel. The friction processed joints are evaluated for their integrity and quality aspects. Friction welding of austenitic stainless steel was carried out using a KUKA friction welding machine (Germany). As the friction time increased, the fully plastically deformed zone (region I) in the vicinity of the bond line becomes increased. In contrast, an increase in friction time will decrease the region (region II) where the grains are partly deformed and grown. Tensile test results indicated that, the joint strength is decreased with an increase of the friction time. The detailed fractographic observation confirmed that the rupture occurred mostly at the joint zone and partly through the base material.  相似文献   
76.
77.
Policies regarding ambulance diversion are critical to ensuring that EMS providers are aware of appropriate patient destinations, even before patients enter the system. Field EMS personnel should never be requested to prolong transport time intervals to search for an available hospital at the potential expense of patients' conditions and the immediate availability of out-of-hospital emergency care for the community. The responsibility for providing efficient emergency care to the community rests with all those who contribute to EMS structures and processes. All EMS system participants, including hospitals, EMS providers, local and regional lead agencies, and medical oversight authorities, must work together to create comprehensive ambulance diversion policies that satisfactorily meet each other's needs, while maintaining the highest regard for the needs of EMS patients and the entire community.  相似文献   
78.
Poly(N-isopropylacrylamide-acrylamide-methacrylic acid) [p(NIPa-AAm-Ma)] polymer microgels were prepared by free radical precipitation polymerization method. AgNPs were fabricated in the sieves of polymer network by chemical reduction using AgNO3 salt as a precursor of silver ions. Various techniques like dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared microscopy (FTIR), and UV-Visible spectroscopy were used for characterization of pure and composite microgels. The diameter of AgNPs fabricated in polymeric network was found to be in the range of 10-15 nm. Stimuli responsive behavior of hybrid microgels was same as that of pure microgels. Catalytic efficiency of the hybrid microgels was investigated by reducing 4-Nitroaniline (4-NA) into 4-Aminoaniline (4-AA) using NaBH4 as reducing agent under different conditions of temperature of the medium, concentration of reducing agent, 4-Nitroaniline and hybrid microgels to explore the catalysis process. Kinetic and thermodynamic aspects of reduction of 4-Nitroaniline in the presence of catalyst were also discussed on the basis of values of Arrhenius and Eyring parameters like pre-exponential factor, activation energy, enthalpy of activation and entropy of activation. Catalytic activity of the hybrid microgels was found to be thermally tunable in the temperature range of 25-70 oC. The value of rate constant (k app ) for reduction of 4-NA was minimum at 55 °C, which can be attributed to volume phase transition of the hybrid microgels.  相似文献   
79.
A series of poly(di-n-alkyl itaconic acid esters) with side chain lengths from 7 to 20 carbon atoms have been prepared. For derivatives with chain lengths of 7 to 11 carbons, two glass transition temperatures have been detected. The transition occurring at the lower temperature T2g originates in the side groups and is a result of the independent cooperative relaxation of the alkyl side chains, while that observed at higher temperatures T1g reflects the glass-rubber transition of the main chain backbone and the cooperative motion of the total molecule. Derivatives with chain lengths ?12 carbon atoms display melting temperatures Tm, and measurement of the enthalpy of fusion ΔHf indicates that side chain crystallization takes place with part of each side chain entering into a regularly packed hexagonal lattice.  相似文献   
80.
Seeds of seven species, representing different plant families, have been analyzed for oil and the fatty acid composition of the oils was determined by gas-liquid chromatography. In all the species, the oil content exceeded 10% except Mecaranga peltata and Cubeba officinalis seeds. Fully matured Garcinia cambogia seeds had very high (~50%) oil content.  相似文献   
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