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排序方式: 共有984条查询结果,搜索用时 15 毫秒
71.
Young Erin E.; Baumbauer Kyle M.; Hillyer Jessica; Joynes Robin L. 《Canadian Metallurgical Quarterly》2007,121(5):1073
Recent findings indicate that neonatal injury results in decreased spinal plasticity in adult subjects (E. E. Young, K. M. Baumbauer, A. E. Elliot, & R. L. Joynes, 2007). Previous research has shown that acute manipulations of pain processing (i.e., administration of formalin, carrageenan, capsaicin) result in a loss of spinal behavioral plasticity (A. R. Ferguson, E. D. Crown, & J. W. Grau, 2006). Moreover, neonatal injury results in a lasting reduction in adult spinally mediated plasticity resembling the deficit seen following acute manipulations in adults (E. E. Young et al., 2007). The present study was designed to determine whether the effects of neonatal injury could be prevented by lidocaine administration during the initial healing period. Subjects (injured or uninjured) received lidocaine or saline on 1 of 4 administration schedules (preinjury only, postinjury only, for 24 hr postsurgery, or for 72 hr postsurgery). Results demonstrated that lidocaine administration did not prevent the hypersensitivity and reduced spinal plasticity associated with neonatal injury. This suggests that (a) the mechanisms underlying neonatal injury are independent of peripheral input in the initial healing period and (b) lidocaine is ineffective at preventing long-term spinal plasticity changes following neonatal injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Young Erin E.; Baumbauer Kyle M.; Elliot Audrea; Joynes Robin L. 《Canadian Metallurgical Quarterly》2007,121(5):1095
The present study was designed to evaluate the impact of neonatal injury on adult spinal plasticity in rats. Subjects were randomly assigned to 1 of 4 experimental conditions: (a) hind-paw injury at Postnatal Day (PD) 2, (b) hind-paw injury at PD 5, (c) anesthesia exposure only on PD 2, or (d) anesthesia exposure only on PD 5. Subjects receiving a unilateral neonatal hind-paw injury showed decreased mechanical threshold (hyperalgesia) on the previously injured hind paw throughout development. This decrease in threshold survived spinal transection (at T2) at 12 weeks of age. Injured subjects also showed significant impairment in a spinal instrumental learning task performed by the previously injured hind paw. This disruption of learning indicates a disruption of spinal plasticity that may be due to induction of long-term changes in nociceptive processing within the spinal cord. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Kyle D. Peterson 《Applied Artificial Intelligence》2013,27(7-8):692-706
ABSTRACTThe present paper demonstrates that the performance of an elite track and field sprinter can be predicted by means of the dynamic, nonlinear mathematical method of recurrent neural networks (RNNs). Dataset considers three years of National Collegiate Athletics Association (NCAA) Division I competitions where the student-athlete recorded heart rate variability two days precedent to each competition. Input parameters were selected by transfer entropy via permutation tests. Subsequently, two RNN topologies, Elman and Jordan, were trained with 32 competitions, validated with 7 competitions, and tested against 6 held-out competitions. Resultant RNNs, which possess a sense of time and memory, were able to learn time-dependent sequence of acute adaptation and predict race times with an error of 0.09–0.16 s on held-out test data. Root mean sum of differences of successive R-R intervals (RMSSD), an indicator of parasympathetic tone, and direct current biopotentials, indicator of active wakefulness, were most predictive toward competitive performance for an NCAA Division I male sprinter. 相似文献
74.
Oscar Almer Igor Böhm Tobias Edler von Koch Björn Franke Stephen Kyle Volker Seeker Christopher Thompson Nigel Topham 《International journal of parallel programming》2013,41(2):212-235
In recent years multi-core processors have seen broad adoption in application domains ranging from embedded systems through general-purpose computing to large-scale data centres. Simulation technology for multi-core systems, however, lags behind and does not provide the simulation speed required to effectively support design space exploration and parallel software development. While state-of-the-art instruction set simulators (Iss) for single-core machines reach or exceed the performance levels of speed-optimised silicon implementations of embedded processors, the same does not hold for multi-core simulators where large performance penalties are to be paid. In this paper we develop a fast and scalable simulation methodology for multi-core platforms based on parallel and just-in-time (Jit) dynamic binary translation (Dbt). Our approach can model large-scale multi-core configurations, does not rely on prior profiling, instrumentation, or compilation, and works for all binaries targeting a state-of-the-art embedded multi-core platform implementing the ARCompact instruction set architecture (Isa). We have evaluated our parallel simulation methodology against the industry standard Splash-2 and Eembc MultiBench benchmarks and demonstrate simulation speeds up to 25,307 Mips on a 32-core x86 host machine for as many as 2,048 target processors whilst exhibiting minimal and near constant overhead, including memory considerations. 相似文献
75.
Kyle A. Floyd Adam E. Meyer George Nelson Maria Hadjifrangiskou 《Proteomics. Clinical applications》2015,9(11-12):990-1002
Bacterial urinary tract infections (UTIs) afflict millions of people worldwide both in the community and the hospital setting. The onset, duration, and severity of infection depend on the characteristics of the invading pathogen (yin), as well as the immune response elicited by the infected individual (yang). Uropathogenic Escherichia coli (UPEC) account for the majority of UTIs, and extensive investigations by many scientific groups have elucidated an elaborate pathogenic UPEC life cycle, involving the occupation of extracellular and intracellular niches and the expression of an arsenal of virulence factors that facilitate niche occupation. This review will summarize the current knowledge on UPEC pathogenesis; the host immune responses elicited to combat infection; and it will describe proteomics approaches used to understand UPEC pathogenesis, as well as drive diagnostics and treatment options. Finally, new strategies are highlighted that could be applied toward furthering our knowledge regarding host-bacterial interactions during UTI. 相似文献
76.
77.
Shaojun Tian William S. A. Kyle &Darryl M. Small 《International Journal of Food Science & Technology》1999,34(1):33-39
Summary The protein and starch fractions of field pea ( Pisum sativum L.) are potentially a source of novel ingredients for food processing. As part of research to elucidate the functional properties of field pea proteins, the pilot scale extraction of proteins has been undertaken. Two different approaches have been used and the recoveries of protein compared. The first involved extraction with a salt solution followed by decanting and clarification to remove solids. The solution was then further concentrated and salt removed by ultrafiltration and diafiltration. The second procedure was based upon alkaline extraction followed by decanting and recovery by isoelectric precipitation and neutralisation. Both spray drying and freeze drying methods were employed. The protein isolates have been compared and characterised with respect to solubility, chemical composition and to electrophoretic patterns. Overall, the proteins extracted with salt exhibited better physical properties than proteins extracted with alkali, in terms of colour and particle size. The solubilities showed little variation and the electrophoretic patterns were similar. Freeze drying resulted in isolates with darker colour compared with spray drying. 相似文献
78.
Michael L. Schummer Scott A. Petrie Robert C. Bailey 《Journal of Great Lakes research》2008,34(1):54-71
Although numbers of buffleheads (Bucephala albeola), common goldeneyes (Bucephala clangula) and long-tailed ducks (Clangula hyemalis) over-wintering on Lake Ontario have increased substantially over the past two decades, factors influencing habitat use and the potential for competition have not been investigated. The purpose of this study was to determine the relationship between prey availability and community structure of diving ducks during winter on northeastern Lake Ontario. Benthic and nektonic samples collected during fall, winter, and spring 2002–2004 indicated that macroinvertebrate numbers differed by location but generally did not decline throughout winter. Large accumulations of macroinvertebrates, apparently moved by wave action and currents, were documented in nearshore areas. Surveys showed that diving ducks congregated in mixed species flocks within areas of higher food abundance. Mixed species flocks were common in nearshore areas, likely because energydense foods (Amphipoda and Chironomidae) were abundant in the narrow zone of shallow water, close to shore. Although macroinvertebrate numbers likely affected habitat use by diving ducks, birds did not greatly reduce abundance of macroinvertebrates. It is unlikely that exploitative competition was occurring and interference competition appeared below threshold levels that would cause species to spatially segregate. Overall, our results suggest that food availability is not a limiting factor for buffleheads, common goldeneyes, or long-tailed ducks wintering on northeastern Lake Ontario. 相似文献
79.
In some cases, the search for a conjunction target proceeds through the smaller group of elements in a display, whereas in others, search is limited to those elements that share a particular feature with the target. In 6 experiments, participants searched for a conjunction target among displays consisting of various proportions of 2 distractor types. Smaller-group search was more prevalent than target-feature search with denser displays and with features that were highly discriminable. Explicit instructions to limit search to a specific feature affected performance only when the discriminability of the guiding feature was much greater than the other target feature. Together, these experiments show that bottom-up factors have more influence in guiding conjunction searches than previously thought. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Surface pressure and wind load characteristics on prisms immersed in a simulated transient gust front flow field 总被引:1,自引:0,他引:1
Kyle Butler Shuyang Cao Ahsan Kareem Yukio Tamura Shigehira Ozono 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(6-7):299-316
Thunderstorm generated gust fronts are responsible for various degrees of structural damage in many areas of the world. However, the resulting impact of gust front winds is not fully understood to such a level that their flow kinematics, dynamics and impact on structures can be quantified with some certainty. Gust front winds are transient in nature and have a flow profile which differs significantly from a typical boundary layer flow field. This study focuses on investigating the effects of this flow profile and its transient nature on the aerodynamics of bluff, prismatic bodies. A gust front type flow field is generated using a multiple fan wind tunnel and the resulting surface pressures are captured on a suite of prismatic models, which vary in size in relationship to the oncoming wind profile. The temporal variations in surface pressures are analyzed using traditional time, frequency and time-frequency domain schemes. Results indicate the changing nature of the surface pressure field in time, highlighting both qualitative and quantitative differences between local and area-averaged pressures under a host of flow profiles. 相似文献