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61.
This paper describes a novel, binary search pose estimation (BSPE) technique for poses constrained to 3 degrees of freedom (DOF). The technique requires three fiduciary marker points and operates by minimising the angular DOF through a binary search driven algorithm. The technique is less computationally intensive than the standard closed form solutions and quickly converges to a solution which can be verified if additional fiduciary points are available. Evaluation for the technique is presented through a comparison to pose from orthography and scaling with iterations (POSIT) using synthetic data and a real-world application, where the technique is used for pose estimation of a mobile robot with respect to a motor vehicle for inspection purposes.  相似文献   
62.
Selective breeding of salmonid fishes for the purpose of commercial aquaculture has resulted in domesticated strains possessing a divergent physiological and behavioral phenotype from that of wild conspecifics. Freshwater production of rainbow trout (Oncorhynchus mykiss) has been occurring in regions of Lake Huron, Canada, for decades yet the growth and performance of domestic (aquaculture) versus wild (naturalized) strains are poorly understood. We conducted two trials to examine growth differences between size-matched wild and domestic strains of juvenile rainbow trout: (1) reared separately and fed to satiation; and (2) reared together and fed a reduced ration to induce competition. Additionally, we used bioenergetics models to assess strain-specific growth rates across a range of water temperatures (5, 10, 15 and 18 °C) as well as Lake Huron temperatures during the open-water season. Domestic rainbow trout showed a growth advantage throughout the 102 d trials, and by the end of the study had achieved a mass > two-fold that of the wild strain and had greater fork length, condition, and thermal growth coefficient (TGC) under both treatments. Rapid growth of domestic strain fish was achieved through the combination of enhanced feed consumption (by ~ 40%) and feeding efficiency (up to 60% lower feed conversion ratio) relative to wild fish. Divergence in growth rates between strains was most pronounced (> 3 ×) when modeled with Lake Huron open-water temperatures. We demonstrate that the growth and feed-conversion efficiency differ significantly between these two strains of rainbow trout under laboratory conditions, suggesting that differences could be even greater in nature.  相似文献   
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557 Asian-American students (263 Chinese Americans, 185 Japanese Americans, and 109 Korean Americans) completed a survey consisting of a demographic questionnaire, a modified version of the Suinn-Lew Asia Self-Identity Acculturation Scale, and the Attitudes Toward Seeking Professional Psychological Help Scale (ATSPHS). A 3?×?2?×?2 multivariate analysis with main effects of ethnicity, gender, and level of acculturation and the 4 subscales of the ATSPHS as the dependent variables resulted in a significant F value for acculturation effect and nonsignificant F values for all other main and interaction effects. Regardless of ethnicity and gender, the most acculturated students were: (a) most likely to recognize personal need for professional psychological help, (b) most tolerant of the stigma associated with psychological help, and (c) most open to discussing their problems with a psychologist. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Fall und Kommentare

Sch?n warm zudecken ...  相似文献   
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Traceability of wines requires knowledge of their characteristics, which are associated with the geographical origin of grape, soil, water, climate as well as the winery techniques. The aim of this work was to classify wines and soil from three production areas of Argentina according to multielement data. The influence of the provenance soil on the wine element composition was also investigated.Eleven elements were determined in 31 wine samples and 137 soil samples from regions under study. Stepwise discriminant analysis allows us to correctly classify 100% of the wines analysed from the three regions using only seven parameters (K, Fe, Ca, Cr, Mg, Zn and Mn) and 92% correct classification for soils using seven variables (Ca, Cr, K, Fe, Cu, Zn and, Mg). Canonical analysis between soils and wines datasets affords a correlation coefficient of 0.85 (P-value < 0.001). Thus, almost 85% of variability observed amongst wines could be attributed to the soil in which the vines were cultivated.The analysis of elemental concentrations in the wines and soils, in combination with chemometrics, provides a powerful tool to verify the geographical origin of wines.  相似文献   
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Object

In the present study, we aimed to evaluate the impact of neurodegeneration of the nigrostriatal tract in a rodent model of Parkinson’s disease on the different MR contrasts (T2, T1, CBF and CBV) measured in the striatum.

Material and methods

Animals were injected with 6-hydroxydopamine (6OHDA) in the substantia nigra resulting in massive loss of nigrostriatal neurons and hence dopamine depletion in the ipsilateral striatum. Using 7T MRI imaging, we have quantified T2, T1, CBF and CBV in the striata of 6OHDA and control rats. To validate the lesion size, behavioral testing, dopamine transporter μSPECT and tyrosine hydroxylase staining were performed.

Results

No significant differences were demonstrated in the absolute MRI values between 6OHDA animals and controls; however, 6OHDA animals showed significant striatal asymmetry for all MRI parameters in contrast to controls.

Conclusions

These PD-related asymmetry ratios might be the result of counteracting changes in both intact and affected striatum and allowed us to diagnose PD lesions. As lateralization is known to occur also in PD patients and might be expected in transgenic PD models as well, we propose that MR-derived asymmetry ratios in the striatum might be a useful tool for in vivo phenotyping of animal models of PD.  相似文献   
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