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91.
92.
Trace Amine-Associated Receptor 1 (TAAR1) is a potential target for the treatment of depression and other CNS disorders. However, the precise functional roles of TAAR1 to the actions of clinically used antidepressants remains unclear. Herein, we addressed these issues employing the TAAR1 agonist, o-phenyl-iodotyramine (o-PIT), together with TAAR1-knockout (KO) mice. Irrespective of genotype, systemic administration of o-PIT led to a similar increase in mouse brain concentrations. Consistent with the observation of a high density of TAAR1 in the medial preoptic area, o-PIT-induced hypothermia was significantly reduced in TAAR1-KO mice. Furthermore, the inhibition of a prepulse inhibition response by o-PIT, as well as its induction of striatal tyrosine hydroxylase phosphorylation and elevation of extracellular DA in prefrontal cortex, were all reduced in TAAR1-KO compared to wildtype mice. O-PIT was active in both forced-swim and marble-burying tests, and its effects were significantly blunted in TAAR1-KO mice. Conversely, the actions on behaviour and prefrontal cortex dialysis of a broad suite of clinically used antidepressants were unaffected in TAAR1-KO mice. In conclusion, o-PIT is a useful tool for exploring the hypothermic and other functional antidepressant roles of TAAR1. By contrast, clinically used antidepressants do not require TAAR1 for expression of their antidepressant properties.  相似文献   
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Limiting the discussion to an associative von‐Mises plasticity model with linear kinematic and isotropic hardening, we compare the performance of the classical radial return map algorithm with a new integration scheme based on the computation of an integration factor. The numerical examples clearly show the improved accuracy of the new method. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
95.
We consider four schemes based on generalized midpoint rule and return map algorithm for the integration of the classical J2 plasticity model with linear hardening. The comparison, aiming to establish which is the preferable scheme among the four considered, is both theoretical and numerical. On one side, extending and completing the existing results in the literature, we investigate the four schemes from the theoretical viewpoint, addressing in particular the existence of solution, long‐term behaviour, accuracy and stability. On the other hand, we develop an extensive set of numerical tests, based on pointwise stress–strain loading histories, iso‐error maps and initial boundary‐value problems. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
96.
Over a 6-year period (1989-1995), gastrointestinal (GI) perforation was diagnosed in nine preterm infants (mean gestational age 27 weeks, mean birth weight 872 g). Three presented with necrotizing enterocolitis (NEC), two with indwelling-tube-induced perforation of the stomach, one with small-left-colon syndrome, and another with meconium ileus. Spontaneous intestinal perforation occurred in two similar very-low-birth-weight (VLBW) infants, in the distal ileum, on days 8 and 9 of life, respectively. The only clinical sign was extensive abdominal distension, and abdominal X-ray studies revealed free peritoneal air. All findings were distinct from those associated with NEC. Their further clinical course was complicated by reperforation on day 32 and 39, respectively. They subsequently recovered and presented without GI problems at the corrected ages of 4 and 2 months, respectively. In contrast to high mortality of 57% in the group with non-spontaneous intestinal perforations, spontaneous perforation seems to have a good prognosis even in VLBW infants if diagnosed and treated promptly.  相似文献   
97.
The two-dimensional antiferromagnetic correlations found for LiCuVO4 below 30 K have been explained by considering the ordered distribution of lithium and copper in the octahedral sites.  相似文献   
98.
99.
Li3x La(1–x )VO4(0x0.3) solid solutions have been obtained by thermal treatment of lanthanum and lithium nitrates with V2O5 in the temperature range 700–980 K. The crystal structure of these single phases has been refined by the Rietveld analysis of powder X-ray diffraction data. The structure refinement of Li0.15La0.95VO4 by neutron diffraction has been also achieved at 295 K. This compound adopts a distorted monazite-type structure: space group P21/n, a=0.7047(1) nm b=0.7283(6) nm c=0.6726(8) nm, =104.86(1)°, Z=4.  相似文献   
100.
Several emerging technologies are being explored to increase the efficiency of machining nickel based alloys. These include the so-called assisted machining processes. Within that group, use of high-pressure cooling has been increasing since its introduction in the 1950s by Pigott and Colwell. The present study compares changes in tool wear patterns for high-pressure cooling (HPC) with those for flood cooling during rough face-turning of wrought nickel-based alloy IN 718. The alloy was face-turned with uncoated carbide tools at a contact cutting speed of 30?m/min, using conventional and high-pressure coolants (HPCs) at 8?MPa (80?bar). Tool wear and cutting force components were recorded. HPC reduced flank wear more than 30%, and reduced cutting forces by more than 10%. In contrast, notch wear is higher and becomes predominant in HPC. Temperatures during turning were also measured and compared to the results obtained from finite element modeling to better understand differences in the notch formation tendency for HPCs compared with conventional.  相似文献   
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