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11.
Parallel communicating grammar systems with regular control (RPCGS, for short) are introduced, which are obtained from returning regular parallel communicating grammar systems by restricting the derivations that are executed in parallel by the various components through a regular control language. For the class of languages that are generated by RPCGSs with constant communication complexity we derive a characterisation in terms of a restricted type of freely rewriting restarting automaton. From this characterisation we obtain that these languages are semi-linear, and that for RPCGSs with constant communication complexity, the centralised variant has the same generative power as the non-centralised variant. 相似文献
12.
Rat strain differences in the acoustic startle response (ASR) and prepulse inhibition (PPI) of that response are of increasing interest, especially as the genetics of PPI may provide an approach to studying the genetics of certain mental illnesses. However, strain differences in PPI are confounded by differences in ASR. To clarify this issue, the authors investigated the ASR and PPI across a range of startling stimulus intensities (70 dB-120 dB) in Wistar and Sprague-Dawley rats (N=96). Sprague-Dawleys showed more PPI of ASR capacity (response limit) than Wistars. In contrast, Wistars exhibited greater PPI than Sprague-Dawleys, as measured by an increase in response threshold. This dissociation suggests that PPI is more complex than that assessed by single startling stimulus intensity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Machine Learning - We investigate the problem of model selection in the setting of supervised learning of boolean functions from independent random examples. More precisely, we compare methods for... 相似文献
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15.
Mohammad A. Hassanain Thomas M. Froese Dana J. Vanier 《Canadian Metallurgical Quarterly》2003,17(1):51-64
This paper presents the development of a generic framework for asset maintenance management. The framework has been presented in the form of an IDEF0 process model. The process model served to illustrate the interaction and dependencies among a diverse set of knowledge areas. In this framework, outputs from one management process become inputs to another in a subsequent hierarchy. The structure of the framework model exhibited the characteristics of flexibility and robustness. Updates in knowledge can be accommodated within the framework through incorporating new management processes and/or activities, as well as establishing new sequencing logic for these processes and/or activities. In a supporting effort to the development of the framework model, the writers have objectively reviewed the general capabilities of three commercially available software applications that are known within the asset management (AM) industry. These three applications, while encompassing a wide selection of capabilities, represent a typical selection of information technology (IT) tools and techniques that are widely used in strategic AM practices. The objective of this review is to study the operational characteristics and functionalities, and to assess the capability of software interoperability, of a representative sample of IT tools known within the AM industry. 相似文献
16.
We raise the question of approximating the compressibility of a string with respect to a fixed compression scheme, in sublinear time. We study this question in detail for two popular lossless compression schemes: run-length encoding (RLE) and a variant of Lempel-Ziv (LZ77), and present sublinear algorithms for approximating compressibility with respect to both schemes. We also give several lower bounds that show that our algorithms for both schemes cannot be improved significantly. Our investigation of LZ77 yields results whose interest goes beyond the initial questions we set out to study. In particular, we prove combinatorial structural lemmas that relate the compressibility of a string with respect to LZ77 to the number of distinct short substrings contained in it (its ?th subword complexity , for small ?). In addition, we show that approximating the compressibility with respect to LZ77 is related to approximating the support size of a distribution. 相似文献
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This study examined the individual and combined effects of exposure to positive Latino exemplars and prototypes in the media on White audience members' attitudes about and judgments regarding Latinos in society. Although it was expected that exposure to these favorable models would promote positive evaluations of Latinos among White consumers, the extent to which one mode of presentation could be privileged in the production of more beneficial outcomes was uncertain based on existing research. These results cautiously indicate that while prototypes may offer some advantages in terms of reducing stereotyping, both exemplar‐ and prototype‐based characterizations of positive race‐related media content (alone and in combination) can positively influence consumers' perceptions of target racial/ethnic groups. 相似文献
18.
King Eden B.; Dunleavy Dana G.; Dunleavy Eric M.; Jaffer Salman; Morgan Whitney Botsford; Elder Katie; Graebner Raluca 《Canadian Metallurgical Quarterly》2011,17(1):54
Although scholars agree that traditional forms of discrimination have generally been supplanted by subtler interpersonal manifestations of discrimination, it is yet unknown whether targets of these behaviors or the American judicial branch recognize such negative behaviors as violations of extant law. Extending research and theory, we propose that denigrating messages toward women and ethnic minorities (i.e., microaggressions) emerge in workplace interactions and are sometimes interpreted as discrimination. Specifically, this research explores the presence, severity, and frequency of microaggressions that appear in a random sample of race and gender discrimination cases in federal court dockets since the year 2000. The results suggest that microinsults, microinvalidations, and microassaults are reported in a variety of discrimination claims. However, only overt and intentional forms of microaggressions (microassaults) increased the likelihood that decisions favored plaintiffs. Thus, there may be a disconnect between forms of discrimination perceived by claimants and how those forms are evaluated by the legal system that protects victims of discrimination. This potential misalignment of science and practice is discussed, as are directions for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
19.
Voss Horrell Sarah C.; Holohan Dana R.; Didion Lea M.; Vance G. Todd 《Canadian Metallurgical Quarterly》2011,42(3):283
Reports an error in Treating traumatized OEF/OIF veterans: How does trauma treatment affect the clinician by Sarah C. Voss Horrell, Dana R. Holohan, Lea M. Didion and G. Todd Vance (Professional Psychology: Research and Practice, 2011[Feb], Vol 42[1], 79-86). The word “While” was erroneously inserted in the first sentence of the “Clinician Factors” section. The corrected sentence is provided in the erratum. (The following abstract of the original article appeared in record 2011-04544-011.) The authors of this article describe the rewards and challenges for clinicians treating veterans who have served in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF). Issues of vicarious trauma, secondary traumatic stress, compassion fatigue, and burnout are defined and reviewed, as are compassion satisfaction and posttraumatic growth. Patient, clinician, and organizational characteristics that are likely to affect clinicians working with this clinical population are discussed. Patient factors that may increase strain on clinicians are discussed such as age, likelihood of redeployment, comorbid conditions, attendance issues, and elevated risk for suicide and aggression. Clinician factors, such as theoretical orientation, training, supervision, military affiliation, personal trauma history, spirituality, social support, and self-care, are also discussed as possible risk and protective factors for vicarious trauma and burnout. Organizational influences, such as caseload size and diversity, clinician control and autonomy, use of evidence-based practices, availability of resources, rural isolation, and the philosophy of the clinic, are further discussed. Recommendations for ameliorating risks are discussed relative to each area and include allowing clinicians to plan their own appointments so as to balance their caseload of OEF/OIF veterans, attending to self-care practices, and having a supportive team with thorough training in evidence-based practices. Future empirical research is needed on risk and resiliency factors for clinicians working with traumatized OEF/OIF veterans given that this population is likely to grow. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
20.
Paul-Mihai Boarescu Ioana Boarescu Raluca Maria Pop tefan Horia Roian Ioana Corina Bocan Vasile Rus Rzvan Olimpiu Mada Iulia Diana Popa Nicholas Neagu Adriana Elena Bulboac Anca Dana Buzoianu Sorana D. Bolboac 《International journal of molecular sciences》2022,23(3)
The present study aims to compare the oxidative stress biomarkers, pro-inflammatory cytokines, and histological changes induced by three cardiovascular risk factors, namely, hypertension, dyslipidemia, and type 1 diabetes mellitus. Hypertension was induced with 40 mg/kg body weight (b.w.) of N omega-nitro-L-arginine-methyl (L-NAME) administered orally. Dyslipidemia was induced by the administration of a diet with a high cholesterol (2%) content. Diabetes mellitus was induced by intraperitoneal administration of a single dose of streptozocin (65 mg/kg). Malondialdehyde (MDA) and total oxidative status (TOS) are increased by all three cardiovascular risk factors (up to 207%). The indirect assessment of NO synthesis (NOx) is observed to be reduced after L-NAME administration (43%), and dyslipidemia induction (16%), while type 1 diabetes mellitus is associated with the highest levels of NOx (increased 112%). Hypertension, dyslipidemia, and type 1 diabetes reduced the total antioxidative capacity (TAC) and total thiol (SH) levels (up to 57%). The values of evaluated pro-inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), assessed from the ascending aorta were elevated by all three cardiovascular risk factors, with the highest levels induced by type 1 diabetes mellitus (up to 259%). The histopathological examination of the ascending and descending aorta revealed reversible pro-atherogenic changes consisting of the accumulation of lipid droplets in the subendothelial connective tissue on rats with hypertension and dyslipidemia. Irreversible pro-atherogenic changes consisting of a reduction of the specific elasticity of the arteries were observed in rats with type 1 diabetes mellitus. Type 1 diabetes mellitus demonstrates an alteration of the oxidative stress parameters, the elevation of tissue levels of the pro-inflammatory cytokines and causing irreversible pro-atherogenic changes on the aortic wall. 相似文献