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51.
OBJECTIVE: To estimate sensitivity and accuracy of subjective evaluation of mild lameness in horses during treadmill locomotion and to correlate subjective evaluation with kinematic analysis. ANIMALS: 19 lame and 5 clinically normal horses. PROCEDURE: Lameness was evaluated by subjective score and kinematic analysis before and after palmar digital nerve block (PDNB). Evaluations were made by 6 clinicians and 7 interns or residents. Within- and between-observer agreement analyses (kappa values) were calculated and compared, using a Student's t-test. Pearson's product-moment correlation coefficients were calculated between clinician's change in score and the change in kinematic variables after PDNB. RESULTS: Within-observer agreement was within the range expected for conditions of moderate diagnostic difficulty. Within-observer agreement was higher for clinicians than for interns or residents. Between-observer agreement was acceptable for scores within 1 value of each other. Between-observer agreement of change in lameness score after PDNB was poor. When kinematic variables were ranked with each clinician's subjective change in score, only 2 were among the top 3 for the majority of clinicians. Asymmetry of vertical head movement between contralateral forelimb stance phases and the point of maximum hoof height during swing decreased as lameness subjectively improved. CONCLUSION: Mild lameness may be difficult to evaluate during treadmill locomotion. Although clinicians were more repeatable in their subjective evaluation of lameness than interns or residents, they were not more reliable at detecting the true state of lameness. CLINICAL RELEVANCE: Lack of agreement between clinician scoring of mild lameness emphasizes the need to use more objective measures for quantifying lameness.  相似文献   
52.
A novel fabrication procedure of high critical temperature superconductor Josephson junctions (HTCSJJ) has been developed by a 90° rotation of YBa2Cu3O7–x c-axis around an in-plane direction, on the basis of concepts of the biepitaxial technique. YBa2Cu3O7–x grows oriented along (001) direction on a MgO seed layer deposited on a (110) SrTiO3 substrate and along (110) direction on the bare substrate. Josephson junctions of good quality were obtained exhibiting RSJ behavior and features characteristic of HTCSJJ phenomenology. Even if not uniform, in some samples, the nature of the critical currentI c is completely Josephson, as resulting from theI c dependence on the applied magnetic field. The maximum measuredI c R N value atT=4.2K is 2mV.  相似文献   
53.
In a multistage interconnection network (MIN) the calculation of the number of permutations of the input terminals into the output terminals is a classic difficult problem. In this paper, we introduce an innovative technique based on Colored Petri Nets (known as CP-nets or CPNs) that will allow us to analyze the permutation capability of arbitrary MINs. We show how to verify whether a MIN is rearrangeable through the state space analysis of the associated CP-net and we measure the permutation capability of non-rearrangeable MINs in terms of the permutations that can be generated. The proposed approach takes advantage of powerful existing software tools, particularly, CPNTools, which is used to explore the occurrence graphs of CP-nets and determine the set of permutations performed by the modeled MINs. This new technique is easy to use and can be efficiently applied to MINs made of cross-bar switches.  相似文献   
54.
A novel fully CMOS circuit for electronic telephone line adaption is described. In the on-hook state the circuit operates in micropower condition, dissipates only 5 A, and is capable of generating the supply voltage required for retention of data stored on external RAM. In the off-hook state the circuit is boosted into the normal operation mode and is able to drive external bipolar transistors to synthesize the line impedance. The dc and the ac line impedances are set with external components, thus permitting the fulfillment of different PTT specifications. The circuit also performs line signal extraction and transmission, both for voice and DTMF. The dc line voltage is monitored, and a supervision block generates a precise reset signal when the line voltage drops out. The circuit has been integrated in a CMOS P-well 3-m double-poly single-metal technology; the silicon area is 6 mm2.  相似文献   
55.
Glycosaminoglycans (GAGs) are important in a number of biological processes and are structurally altered in many pathological conditions. The complete determination of GAG primary structures has been hampered by the lack of sensitive and specific analytical techniques. Nuclear magnetic resonance spectroscopy (NMR) is a powerful tool for GAG structure elucidation despite its relatively poor limits of detection. Solenoidal microcoils have greatly enhanced the mass limits of detection of NMR, enabling the on-line coupling of microseparation and concentration techniques such as capillary isotachophoresis (cITP), which can separate and concentrate analytes by 2-3 orders of magnitude. We have successfully used cITP coupled with on-line NMR detection to separate and concentrate nanomole quantities of heparin oligosaccharides. This sensitive on-line measurement approach has the potential to provide new insights into the relationships between biological function and GAG microstructures.  相似文献   
56.
Zeolitic imidazolate frameworks (ZIFs), a subclass of metal–organic frameworks (MOFs) built with tetrahedral metal ions and imidazolates, offer permanent porosity and high thermal and chemical stabilities. While ZIFs possess some attractive physical and chemical properties, it remains important to enhance their functionality for practical application. Here, an overview of the extensive strategies which have been developed to improve the functionality of ZIFs is provided, including linker modifications, functional hybridization of ZIFs via the encapsulation of guest species (such as metal and metal oxide nanoparticles and biomolecules) into ZIFs, and hybridization with polymeric matrices to form mixed matrix membranes for industrial gas and liquid separations. Furthermore, the developed strategies for achieving size and shape control of ZIF nanocrystals are considered, which are important for optimizing the textural characteristics as well as the functional performance of ZIFs and their derived materials/hybrids. Moreover, the recent trends of using ZIFs as templates for the derivation of nanoporous hybrid materials, including carbon/metal, carbon/oxide, carbon/sulfide, and carbon/phosphide hybrids, are discussed. Finally, some perspectives on the potential future research directions and applications for ZIFs and ZIF‐derived materials are offered.  相似文献   
57.
In this study, a series of experiments was conducted in order to investigate the mechanisms of tensile force reduction and martensitic transformation in SUS304 stainless steel during ultrasonic vibration assisted tensile tests (UAT).

An independent analysis of the impact of the stress superposition effect in the ultrasound assisted tensile tests was done by finite element simulation, and metallographic analysis on the specimens showed that the increase of the amplitude of the ultrasonic vibration has a great influence on the martensite transformation in the material during deformation, reducing the elongation of the specimens. The results also pointed out that the tensile force reduction is caused by a combination of the effects of stress superposition and the energy absorption of dislocations over the hardening of the material due to the increase of dislocation density and induced martensitic transformation.  相似文献   

58.
59.
This study investigated the volatile emission from apple (Malus x domestica Borkh., cv. Golden Delicious) foliage that was either intact, mechanically-damaged, or exposed to larval feeding by Pandemis heparana (Denis and Schiffermüller) (Lepidoptera: Tortricidae). Volatiles were collected by closed-loop-stripping-analysis and characterized by gas chromatography-mass spectrometry in three time periods: after 1 h and again 24 and 48 h later. Volatiles for all treatments also were monitored continuously over a 72-h period by the use of proton transfer reaction – time of flight-mass spectrometry (PTR-ToF-MS). In addition, the volatile samples were analyzed by gas chromatography-electroantennographic detection (GC-EAD) using male and female antennae of P. heparana. Twelve compounds were detected from intact foliage compared with 23 from mechanically-damaged, and 30 from P. heparana-infested foliage. Interestingly, six compounds were released only by P. heparana-infested foliage. The emission dynamics of many compounds measured by PTR-ToF-MS showed striking differences according to the timing of herbivory and the circadian cycle. For example, the emission of green leaf volatiles began shortly after the start of herbivory, and increased over time independently from the light-dark cycle. Conversely, the emission of terpenes and aromatic compounds showed a several-hour delay in response to herbivory, and followed a diurnal rhythm. Methanol was the only identified volatile showing a nocturnal rhythm. Consistent GC-EAD responses were found for sixteen compounds, including five aromatic ones. A field trial in Sweden demonstrated that benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole lures placed in traps were not attractive to Pandemis spp. adults, but 2-phenylethanol and phenylacetonitrile when used in combination with acetic acid were attractive to both sexes.  相似文献   
60.
Ovarian clear cell carcinoma (OCCC) is a rare but chemorefractory tumor. About 50% of all OCCC patients have inactivating mutations of ARID1A, a member of the SWI/SNF chromatin-remodeling complex. Members of the SWI/SNF remodeling have emerged as regulators of the energetic metabolism of mammalian cells; however, the role of ARID1A as a modulator of the mitochondrial metabolism in OCCCs is yet to be defined. Here, we show that ARID1A loss results in increased mitochondrial metabolism and renders ARID1A-mutated cells increasingly and selectively dependent on it. The increase in mitochondrial activity following ARID1A loss is associated with increase in c-Myc expression and increased mitochondrial number and reduction of their size consistent with a higher mitochondrial cristae/outer membrane ratio. Significantly, preclinical testing of the complex I mitochondrial inhibitor IACS-010759 showed it extends overall survival in a preclinical model of ARID1A-mutated OCCC. These findings provide for the targeting mitochondrial activity in ARID1A-mutated OCCCs.  相似文献   
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