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91.
Four experiments examined children's ability to reason about the causal significance of the order in which 2 events occurred (the pressing of buttons on a mechanically operated box). In Study 1, 4-year-olds were unable to make the relevant inferences, whereas 5-year-olds were successful on one version of the task. In Study 2, 3-year-olds were successful on a simplified version of the task in which they were able to observe the events although not their consequences. Study 3 found that older children had difficulties with the original task even when provided with cues to attend to order information. However, 5-year-olds performed successfully in Study 4, in which the causally relevant event was made more salient. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Margarita Mediavilla Juan-Carlos Fraile Ignacio J. Galindo M. Teresa González 《Journal of Intelligent and Robotic Systems》2003,38(1):85-104
Strategy-based path planning was introduced by the authors as a way to give robotic manipulators some sort of reactive behaviour in dynamic and unpredictable environments. This approach is based on making robots react to moving obstacles using a restricted subset of the configuration space, and on using an off-line pre-planning stage to choose the restricted subset. In this paper, strategy-based path planning is applied and explored, focusing our attention on the off-line stage. It is applied to the joint motion of two and three robots that perform pick and place tasks sharing common working areas. 相似文献
93.
This paper addresses the issue of improving the performance of memory management for real-time Java applications, building upon the real-time specification for Java (RTSJ) from the Real-Time Java Expert Group. In a first step, a collecting dynamic memory solution including both a real-time garbage collector and region-based memory management, is proposed. A thorough analysis of the parameters influencing the performance of write barriers in memory management, together with ways of improvement are then presented. Finally, the implementation of a memory management solution compliant with the RTSJ and integrating the proposed improvements is sketched. 相似文献
94.
Ravi Rajwar Alain Kägi James R Goodman 《International journal of parallel programming》2004,32(3):225-258
Communication latencies within critical sections constitute a major bottleneck in some classes of emerging parallel workloads. In this paper, we argue for the use of two mechanisms to reduce these communication latencies: Inferentially Queued locks (IQLs) and Speculative Push (SP). With IQLs, the processor infers the existence, and limits, of a critical section from the use of synchronization instructions and joins a queue of lock requestors, reducing synchronization delay. The SP mechanism extracts information about program structure by observing IQLs. SP allows the cache controller, responding to a request for a cache line that likely includes a lock variable, to predict the data sets the requestor will modify within the associated critical section. The controller then pushes these lines from its own cache to the target cache, as well as writing them to memory. Overlapping the protected data transfer with that of the lock can substantially reduce the communication latencies within critical sections. By pushing data in exclusive state, the mechanism can collapse a read-modify-write sequences within a critical section into a single local cache access. The write-back to memory allows the receiving cache to ignore the push. Neither mechanism requires any programmer or compiler support nor any instruction set changes. Our experiments demonstrate that IQLs and SP can improve performance of applications employing frequent synchronization. 相似文献
95.
Elvev?g Brita; Brown Gordon D. A.; McCormack Teresa; Vousden Janet I.; Goldberg Terry E. 《Canadian Metallurgical Quarterly》2004,113(4):509
Patients with schizophrenia display numerous cognitive deficits, including problems in working memory, time estimation, and absolute identification of stimuli. Research in these fields has traditionally been conducted independently. We examined these cognitive processes using tasks that are structurally similar and that yield rich error data. Relative to healthy control participants (n = 20), patients with schizophrenia (n = 20) were impaired on a duration identification task and a probed-recall memory task but not on a line-length identification task. These findings do not support the notion of a global impairment in absolute identification in schizophrenia. However, the authors suggest that some aspect of temporal information processing is indeed disturbed in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Freitas SP Gonçalves TC Serrão JE Santos-Mallet JR 《Microscopy research and technique》2007,70(4):355-360
Male of Triatoma rubrofasciata has four elongated sac-like reproductive mesodermic accessory glands, lined by an inner single layer of secretory cells, with basal plasma membrane infolds and short apical microvilli, and externally enveloped by a thin visceral muscle layer. The secretory cells have a well-developed rough endoplasmic reticulum, Golgi complex, mitochondria, and secretory granules. In one day old adult the gland cells are poorly developed, presenting small, electron-transparent secretory granules scattered among the rough endoplasmatic reticulum, whereas in three days old adult these cells have the cisternae of the rough endoplasmatic reticulum varing size degree, filled with granular electrondense content. In five days old males the secretory granules increase in diameter, being released to the gland lumen. Therefore, there is an increase of the secretory activity according to male maturation. 相似文献
97.
N. R. Goodman 《技术计量学》2013,55(2):221-228
The Average Run Length of a Cusum chart for controlling a normal mean is calculated by solving the systems of linear equations which approximate the integral equations for the required quantities. The accuracy of approximation by this method is numerically evaluated and the results are compared with those obtained by other approximate methods. The construction and use of a new nomogram based on the contours of Average Run Lengths La . and Lr drawn in the h√n/σ—|μ – k|√n/σ plane is discussed. Numerical examples are given to illustrate the flexibility and convenience provided by this nomogram in the design of Cusum charts. 相似文献
98.
Anna‐Lena Kjøniksen Maria Teresa Calejo Kaizheng Zhu Bo Nyström Sverre Arne Sande 《应用聚合物科学杂志》2014,131(13)
Several different polysaccharides have been added to pluronic F127 (poloxamer 407) gels to test their ability to stabilize the gels against dissolution in aqueous media over time. The studied polysaccharides include κ‐carrageenan, chitosan, hyaluronic acid, pectin, alginate, hydroxyethylcellulose, and ethyl(hydroxyethyl)cellulose. Although all the considered polysaccharides slowed down the dissolution time of the pluronic gels, unmodified polysaccharides only had a modest stabilization effect. However, hydrophobic modification of polysaccharides with a sufficiently long hydrocarbon chain (C16) was found to partly prevent the gels from dissolving for more than 6 months. Shorter hydrocarbon chains did not have the same effect, even at high degrees of hydrophobicity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40465. 相似文献
99.
100.
Maria Teresa Vietri Giovanna DElia Gemma Caliendo Marianna Resse Amelia Casamassimi Luana Passariello Luisa Albanese Michele Cioffi Anna Maria Molinari 《International journal of molecular sciences》2021,22(7)
Prostate cancer (PCa) is globally the second most diagnosed cancer type and the most common cause of cancer-related deaths in men. Family history of PCa, hereditary breast and ovarian cancer (HBOC) and Lynch syndromes (LS), are among the most important risk factors compared to age, race, ethnicity and environmental factors for PCa development. Hereditary prostate cancer (HPCa) has the highest heritability of any major cancer in men. The proportion of PCa attributable to hereditary factors has been estimated in the range of 5–15%. To date, the genes more consistently associated to HPCa susceptibility include mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) and homologous recombination genes (BRCA1/2, ATM, PALB2, CHEK2). Additional genes are also recommended to be integrated into specific research, including HOXB13, BRP1 and NSB1. Importantly, BRCA1/BRCA2 and ATM mutated patients potentially benefit from Poly (ADP-ribose) polymerase PARP inhibitors, through a mechanism of synthetic lethality, causing selective tumor cell cytotoxicity in cell lines. Moreover, the detection of germline alterations in MMR genes has therapeutic implications, as it may help to predict immunotherapy benefits. Here, we discuss the current knowledge of the genetic basis for inherited predisposition to PCa, the potential target therapy, and the role of active surveillance as a management strategy for patients with low-risk PCa. Finally, the current PCa guideline recommendations are reviewed. 相似文献