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21.
KS Choi JJ Nah CU Choi YJ Ko HJ Sohn G Libeau SY Kang YS Joo 《Canadian Metallurgical Quarterly》2003,96(1):1-16
An experimental competitive enzyme-linked immunosorbent assay (morbillivirus cELISA) using a recombinant N antigen (rRPV N) expressed in a baculovirus and a ruminant morbillivirus (RPV and PPRV)-specific monoclonal antibody (P-13A9) was developed for simultaneous detection of rinderpest virus (RPV) and peste des petits ruminants virus (PPRV) antibodies and its diagnostic performance was evaluated. A set of known reference antisera against RPV and PPRV belonging to different lineages, experimental sera from cattle vaccinated for a RPV of Asian lineage, and field sera from cattle and sheep/goat populations known to be positive (West Africa) and negative (Korea) for RPV and PPRV were used for the evaluation. Morbillivirus cELISA results on the panel of experimental RPV and PPRV antisera showed high correlation (r=0.97) between the whole virus and the rRPV N antigens, suggesting that the rRPV N contains a ruminant morbillivirus-specific antigenic determinant recognized by the P-13A9 and it may be suitable as an ELISA antigen in place of the whole virus. Morbillivirus cELISA detected anti-RPV and anti-PPRV antibodies in all reference RPV and PPRV antisera containing VN titers >/=1:8, suggesting that the assay can simultaneously detect antibodies against RPV and PPRV. Anti-RPV antibody was detected by morbillivirus cELISA in vaccinated cattle as early as the VNT and continued to be detectable by both the cELISA and the VNT until termination of the study. When applied to field samples from Africa, morbillivirus cELISA showed good agreement with a RP cELISA kit (kappa value of 0.86) in bovine sera and with a peste des petits ruminant cELISA kit (kappa value of 0.81) in caprine/ovine sera. Usefulness of morbillivirus cELISA using the rRPV N protein was discussed. 相似文献
22.
K.Y. Rhee 《Composite Structures》1993,26(3-4):109-113
The single specimen technique is effectively used in classical fracture mechanics for evaluating the J-integral from a single test record. It was previously shown using a cracked lap shear specimen that the technique can be applied to composite structures and the energy release rate of composite laminates can be determined from a single test specimen. The objective of this investigation is to determine the ηel form of a double cantilever beam (DCB) specimen, and to compare it with that of a compact tension (CT) specimen. The result showed that while ηel is linearly related to crack length for the CT specimen, it is proportional to the reciprocal of the crack length for the DCB composite specimen. Also, GIc determined from the compliance method was compared with that determined from the ηel approach. The result showed that the ηel form determined from a single beam analysis can be used to determine GIc from a single test record. 相似文献
23.
The effects of batrachotoxin (BTX) on cloned alpha-subunit Na+ channels were examined in CHO-K1 cells (a chinese hamster ovary cell line) transfected with rat brain NaIIA cDNA. Under whole-cell patch clamp conditions, BTX shifted the voltage dependence of the activation process by about 45 mV towards the hyperpolarizing direction and eliminated the inactivating phase of Na+ currents. Repetitive depolarizations greatly facilitated the binding of BTX with NaIIA channels while the membrane was held at -100 mV. In chloramine-T-pretreated cells, the association rate of BTX binding with the NaIIA channel was 6.5-fold faster than that in untreated cells. The estimated association rate constant for BTX binding with the open form of NaIIA channel was 1.11 x 10(6) mol-1.s-1 at room temperature. BTX-modified NaIIA channels were blocked by tetrodotoxin (TTX) in a complicated manner. First, the TTX binding to the closed state of BTX-modified NaIIA channels was not voltage dependent. The KD value of TTX was measured at 8.9 nM, which was similar to that of unmodified channels (KD = 14.2 nM). Second, the block of the open state of BTX-modified NaIIA channels by TTX was voltage dependent; depolarization reduced the potency of TTX block between -20 mV to +50 mV. Below -30 mV, the TTX affinity began to level off, probably because of the increased presence of the closed state. Unexpectedly, steady-state inactivation of BTX-modified NaIIA channels was minimal as measured by the two-pulse protocol, a phenomenon distinctly different from that found in GH3 cells.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
24.
S. Nourbakhsh W. H. Rhee O. Sahin H. Margolin 《Metallurgical and Materials Transactions A》1994,25(7):1501-1507
A series of single-crystal Al2O3-fiber-reinforced Ni3Al-based intermetallic matrix composites were fabricated by pressure casting. The matrices employed were
binary Ni3Al, Ni3Al-0.5 at. pct Cr, and Ni3Al-0.34 at. pct Zr. The development of microstructure upon oxidation in air at either 1100 °C or 1200 °C was investigated
by optical, scanning, and transmission electron microscopy. In air-oxidized binary Ni3Al, some of the fibers were fully or partially covered with a layer of oxide. A weak fiber/matrix bond in this system, which
led to fiber debonding during composite processing, is believed to be responsible for the ingress of O into the composite
and oxidation of the matrix in the debonded regions at the fiber/matrix interface. Addition of Cr to Ni3Al resulted in an almost threefold increase in fiber/matrix bond strength. No oxidation of the interface was observed. A thick
layer of oxide was formed around all the fibers when the composite was thermally cycled prior to isothermal annealing. Addition
of Zr to Ni3Al resulted in the formation of a layer of ZrO2 on the surface of the fibers during composite processing. The ZrO2 layer provided a fast path for the diffusion of O, which led to the formation of a rootlike oxide structure around the fibers.
The rootlike structure consisted of a network of Al2O3-covered ZrO2. 相似文献
25.
An initial Bentall operation was performed on a patient aged 38 years with annuloaortic ectasia and aortic regurgitation. An echocardiogram and RI angiogram revealed a perigraft aortic aneurysm on the same patient aged 45 years. The aneurysm gradually developed and the maximum diameter reached 90 mm in size. The Redo-Bentall operation (Piehler modification) was successfully done once again on the same patient aged 56 years. The anastmosis between the right coronary orifice and the graft was detached on all sides. The anastmosis between the left coronary orifice and the graft was detached two thirds of all sides. 相似文献
26.
27.
Shi-Woo Rhee 《Korean Journal of Chemical Engineering》1995,12(1):1-11
Aluminum has been used widely as a conducting material in the fabrication of integrated circuits, and chemical vapor deposition
process for Al has been actively investigated for the application in ultra large scale integration. In this review, various
precursors, mainly alkyl aluminum and alane compounds, and reaction mechanisms of these precursors in Al CVI) are described.
Epitaxial growth and selectivity of the deposition are also discussed. In addition to thermal reactions, plasma and photochemical
reactions are also briefly described. 相似文献
28.
The production of the cognitive internal state word know by four 2- to 5-year-old children and their parents was examined. The levels of meaning of cognitive words can be categorized hierarchically along the dimensions of conceptual difficulty and abstractness (see Booth & Hall, 1995). The present study found that children and their parents expressed low levels of meaning less frequently, whereas they expressed high levels of meaning more frequently as a function of age. The children's use of know was also correlated positively with (1) their number of different words produced suggesting that cognitive words are related to more general semantic processes, and (2) with parental use of those same cognitive words suggesting that parental linguistic input may be an important mechanism in cognitive word acquisition. Finally, young children tended to use know more to refer to themselves than to refer to others, whereas their parents tended to use know equally to refer to self and others. The importance of cognitive words in a theory of language acquisition is discussed. 相似文献
29.
Thermal properties and crystalline structure of liquid crystalline (LC) poly(ethylene terephthalate‐co‐2(3)‐chloro‐1,4‐phenylene terephthalate) [copoly(ET/CPT)] were investigated using differential scanning calorimetry (DSC), thermogravimetry (TGA), limiting oxygen index (LOI) measurement, electron dispersive X‐ray analysis (EDX), X‐ray diffractometry, and infrared spectrometry (IR). The thermal transition temperatures of copoly(ET/CPT) were changed with the composition. Copoly(ET/CPT) showed two thermal decomposition steps and the residues at 700°C and LOI values of copoly(ET/CPT) were almost proportional to its chlorine content. The activation energy of thermal decomposition of LC units was very low compared to that of poly(ethylene terephthalate)(PET) units. Crystal structure of copoly(ET/CPT) (20/80) was of triclinic system with the lattice constants of a = 9.98 A?, b = 8.78 A?, c = 12.93 A?, α = 97.4°, β = 96.1°, and γ = 90.8°, which is very close to that of poly(chloro‐p‐phenylene terephthlate) (PCPT) with the lattice constants of a = 9.51 A?, b = 8.61 A?, c = 12.73 A?, α = 96.8°, β = 95.4°, and γ = 90.8°. When copoly(ET/CPT)(50/50) was annealed at 220°C in vacuum, crystallization induced sequential reordering (CISR) was not observed but the heat of fusion was slightly increased due to the increase of the trans isomer content in PET units. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1286–1294, 2002; DOI 10.1002/app.10451 相似文献
30.