Miracle-dz/UniFAR-FTUs huggingface dataset:
Bisimulation Metrics for Continuous Markov Decision Processes

In recent years, various metrics have been developed for measuring the behavioral similarity of states in probabilistic transition systems [J. Desharnais et al., Proceedings of CONCUR'99, Springer-Verlag, London, 1999, pp. 258-273; F. van Breugel and J. Worrell, Proceedings of ICALP'01, Springer-Verlag, London, 2001, pp. 421-432]. In the context of finite Markov decision processes (MDPs), we have built on these metrics to provide a robust quantitative analogue of stochastic bisimulation [N. Ferns, P. Panangaden, and D. Precup, Proceedings of UAI-04, AUAI Press, Arlington, VA, 2004, pp. 162-169] and an efficient algorithm for its calculation [N. Ferns, P. Panangaden, and D. Precup, Proceedings of UAI-06, AUAI Press, Arlington, VA, 2006, pp. 174-181]. In this paper, we seek to properly extend these bisimulation metrics to MDPs with continuous state spaces. In particular, we provide the first distance-estimation scheme for metrics based on bisimulation for continuous probabilistic transition systems. Our work, based on statistical sampling and infinite dimensional linear programming, is a crucial first step in formally guiding real-world planning, where tasks are usually continuous and highly stochastic in nature, e.g., robot navigation, and often a substitution with a parametric model or crude finite approximation must be made. We show that the optimal value function associated with a discounted infinite-horizon planning task is continuous with respect to metric distances. Thus, our metrics allow one to reason about the quality of solution obtained by replacing one model with another. Alternatively, they may potentially be used directly for state aggregation.
Efficient Gradient Estimation for Motor Control Learning

The task of estimating the gradient of a function in the presence of noise is central to several forms of reinforcement learning, including policy search methods. We present two techniques for reducing gradient estimation errors in the presence of observable input noise applied to the control signal. The first method extends the idea of a reinforcement baseline by fitting a local model to the response function whose gradient is being estimated; we show how to find the response surface model that minimizes the variance of the gradient estimate, and how to estimate the model from data. The second method improves this further by discounting components of the gradient vector that have high variance. These methods are applied to the problem of motor control learning, where actuator noise has a significant influence on behavior. In particular, we apply the techniques to learn locally optimal controllers for a dart-throwing task using a simulated three-link arm; we demonstrate that the proposed methods significantly improve the response function gradient estimate and, consequently, the learning curve, over existing methods.
A definitional approach to primitivexs recursion over higher order abstract syntax

It is well known that there are problems associated with formal systems which attempt to combine higher order abstract syntax (HOAS) with principles of induction and recursion. We describe a formal system, called Bsyntax, which we have implemented in Isabelle HOL. Our contribution is to prove the existence of a combinator for primitive recursion with parameters over HOAS. The definition of the combinator is facilitated by the use of terms with infinite contexts. In particular, our work is purely definitional, and is thus consistent with classical logic and choice. An immediate payoff is that we obtain a primitive recursive definition of higher order substitution. We give a presheaf model of Bsyntax, providing additional semantic validation of Bsyntax's principles of recursion. We outline an application of our work to mechanized reasoning about the compiler intermediate language MIL-lite [2].
Variable Platelet Response to Aspirin and Clopidogrel in Atherothrombotic Disease

Humans require rapidly responding, tightly regulated hemostasis because of their closed high-pressure circulatory system. Minor variation in response may predispose to pathological bleeding or thrombosis. In the appropriate setting, pharmacological intervention with antiplatelet therapy stabilizes the atherothrombotic phenotype, though with concomitant hemorrhagic risk. Populations with favorable risk–benefit ratios for acetylsalicylic acid (aspirin) and clopidogrel therapy have nevertheless been defined in major clinical trials. Treatment benefit is established for secondary prevention of cardiovascular and cerebrovascular events, management of acute coronary syndromes, and as an adjunct to percutaneous and surgical revascularization. There is evidence, however, that not all individuals respond comparably to antiplatelet drugs and hence the concept of aspirin and clopidogrel “resistance” has arisen. The term is misleading though because there are many determinants of failure to respond to treatment. Consistent levels of platelet inhibition are required to deliver effective therapy. Adverse consequences of variable response are particularly apparent when antiplatelet drugs are used as an adjunct to coronary revascularization. During percutaneous coronary intervention (PCI), atherosclerotic plaque is invariably disrupted, thrombosis occurs, and endothelial healing is delayed. Intensive periprocedural platelet inhibition minimizes morbidity and mortality, whereas persistence of a prothrombotic environment necessitates chronic antiplatelet therapy. Failure to provide adequate platelet inhibition in all individuals can result in stent thrombosis, myocardial infarction, and death.1,2 Platelet inhibition with aspirin at the time of coronary artery bypass graft surgery also provides benefit. Yet aggressive therapy with aspirin and clopidogrel combined may increase perioperative bleeding in some cases.3 These contrasting clinical problems underlie the need for a tailored approach to therapy and illustrate the requirement for consistent levels of platelet inhibition and a means to confirm individual response. Platelets adhere to sites of vascular injury; however, endothelial disruption is not a prerequisite. Atherosclerotic lesions are associated with impaired endothelial function and hence are …
“Seed-Milarity” Confers to hsa-miR-210 and hsa-miR-147b Similar Functional Activity

Specificity of interaction between a microRNA (miRNA) and its targets crucially depends on the seed region located in its 5′-end. It is often implicitly considered that two miRNAs sharing the same biological activity should display similarity beyond the strict six nucleotide region that forms the seed, in order to form specific complexes with the same mRNA targets. We have found that expression of hsa-miR-147b and hsa-miR-210, though triggered by different stimuli (i.e. lipopolysaccharides and hypoxia, respectively), induce very similar cellular effects in term of proliferation, migration and apoptosis. Hsa-miR-147b only shares a “minimal” 6-nucleotides seed sequence with hsa-miR-210, but is identical with hsa-miR-147a over 20 nucleotides, except for one base located in the seed region. Phenotypic changes induced after heterologous expression of miR-147a strikingly differ from those induced by miR-147b or miR-210. In particular, miR-147a behaves as a potent inhibitor of cell proliferation and migration. These data fit well with the gene expression profiles observed for miR-147b and miR-210, which are very similar, and the gene expression profile of miR-147a, which is distinct from the two others. Bioinformatics analysis of all human miRNA sequences indicates multiple cases of miRNAs from distinct families exhibiting the same kind of similarity that would need to be further characterized in terms of putative functional redundancy. Besides, it implies that functional impact of some miRNAs can be masked by robust expression of miRNAs belonging to distinct families.
Modelling seasonal influenza: the role of weather and punctuated antigenic drift

Seasonal influenza appears as annual oscillations in temperate regions of the world, yet little is known as to what drives these annual outbreaks and what factors are responsible for their inter-annual variability. Recent studies suggest that weather variables, such as absolute humidity, are the key drivers of annual influenza outbreaks. The rapid, punctuated, antigenic evolution of the influenza virus is another major factor. We present a new framework for modelling seasonal influenza based on a discrete-time, age-of-infection, epidemic model, which allows the calculation of the model's likelihood function in closed form. This framework may be used to perform model inference and parameter estimation rigorously. The modelling approach allows us to fit 11 years of Israeli influenza data, with the best models fitting the data with unusually high correlations in which r > 0.9. We show that using actual weather to modulate influenza transmission rate gives better results than using the inter-annual means of the weather variables, providing strong support for the role of weather in shaping the dynamics of influenza. This conclusion remains valid even when incorporating a more realistic depiction of the decay of immunity at the population level, which allows for discrete changes in immunity from year to year.
Slow Recovery from Perturbations as a Generic Indicator of a Nearby Catastrophic Shift

The size of the basin of attraction in ecosystems with alternative stable states is often referred to as “ecological resilience. ” Ecosystems with a low ecological resilience may easily be tipped into an alternative basin of attraction by a stochastic event. Unfortunately, it is very difficult to measure ecological resilience in practice. Here we show that the rate of recovery from small perturbations (sometimes called “engineering resilience”) is a remarkably good indicator of ecological resilience. Such recovery rates decrease as a catastrophic regime shift is approached, a phenomenon known in physics as “critical slowing down. ” We demonstrate the robust occurrence of critical slowing down in six ecological models and outline a possible experimental approach to quantify differences in recovery rates. In all the models we analyzed, critical slowing down becomes apparent quite far from a threshold point, suggesting that it may indeed be of practical use as an early warning signal. Despite the fact that critical slowing down could also indicate other critical transitions, such as a stable system becoming oscillatory, the robustness of the phenomenon makes it a promising indicator of loss of resilience and the risk of upcoming regime shifts in a system.
Therapeutic potential of flavonoids in inflammatory bowel disease: A comprehensive review

The inflammatory process plays a central role in the development and progression of numerous pathological situations, such as inflammatory bowel disease (IBD), autoimmune and neurodegenerative diseases, metabolic syndrome, and cardiovascular disorders. IBDs involve inflammation of the gastrointestinal area and mainly comprise Crohn’s disease (CD) and ulcerative colitis (UC). Both pathological situations usually involve recurring or bloody diarrhea, pain, fatigue and weight loss. There is at present no pharmacological cure for CD or UC. However, surgery may be curative for UC patients. The prescribed treatment aims to ameliorate the symptoms and prevent and/or delay new painful episodes. Flavonoid compounds are a large family of hydroxylated polyphenolic molecules abundant in plants, including vegetables and fruits which are the major dietary sources of these compounds for humans, together with wine and tea. Flavonoids are becoming very popular because they have many health-promoting and disease-preventive effects. Most interest has been directed towards the antioxidant activity of flavonoids, evidencing a remarkable free-radical scavenging capacity. However, accumulating evidence suggests that flavonoids have many other biological properties, including anti-inflammatory, antiviral, anticancer, and neuroprotective activities through different mechanisms of action. The present review analyzes the available data about the different types of flavonoids and their potential effectiveness as adjuvant therapy of IBDs.
The fundamentals of a potentiating learning milieu: expanding capacity for student internalisation and self-regulated learning

In learning communities, academic and social education of students require teachers, as significant and influential role models, to create learning contexts that promote self-regulation, while attending to the psychological needs of competence, autonomy and relatedness. Environments that promote the appropriate balance of autonomy and support enhance rather than undermine an individual's intrinsic enjoyment and desire for learning. In these potentiating learning milieu, self-regulated learners systematically activate and sustain processes towards attainment of goals they personally value. Therefore the challenge for the researchers in this study was to identify the fundamentals of a potentiating learning milieu to provide a practical framework for teachers to expand student learning capacities. This case study draws conclusions from participatory observations within a primary school setting and links the data to social cognitive and social psychological research. Student actions underpinning this social context were interrogated and patterns emerged. The fundamentals of collective values, connected learning, student centred organisation and interpersonal relationships became evident, as common elements were clustered. A pragmatic model was constructed by identifying and implementing these substantive codes, enabling teachers to build capacity to create environments that expand student capacity to learn. This chapter reveals these capacity building fundamentals that provide the opportunity for students to readily self-regulate and internalise their learning towards self-determination.
Disruption of Lymphocyte Function and Signaling in CD45–associated Protein–null Mice

CD45-AP specifically associates with CD45, a protein tyrosine phosphatase essential for lymphocyte differentiation and antigen receptor–mediated signal transduction. CD45 is thought to mediate antigen receptor signaling by dephosphorylating regulatory tyrosine residues on Src family protein tyrosine kinases such as Lck. However, the mechanism for regulating CD45 protein tyrosine phosphatase activity remains unclear. CD45-AP–null mice were created to examine the role of CD45-AP in CD45-mediated signal transduction. T and B lymphocytes showed reduced proliferation in response to antigen receptor stimulation. Both mixed leukocyte reaction and cytotoxic T lymphocyte functions of T cells were also markedly decreased in CD45-AP–null mice. Interestingly, the interaction between CD45 and Lck was significantly reduced in CD45-AP–null T cells, indicating that CD45-AP directly or indirectly mediates the interaction of CD45 with Lck. Our data indicate that CD45-AP is required for normal antigen receptor signaling and function in lymphocytes.
Patterns of Delinquent Behavior Trajectory and Their Effect Factors

This study examined patterns of delinquent behavior trajectory from late childhood to early adolescence and examined relationships between patterns of trajectory and individual, family, and school factors. Youth delinquent behavior trajectories were examined by mixed growth models using data from the 2nd to 5th year surveys of the Seoul Panel Study of Children. Relationships between patterns and effect factors were examined by multinominal logit models. Four patterns emerged: non-delinquency (80%); rapidly accelerating delinquency (3.3%); decelerating delinquency (6.0%); and moderately accelerating (10.7%) groups. Contacts with a delinquent peer group had persistent effects on more serious delinquent behavior trajectories. Increased levels of self-esteem and school achievement prevented increase in delinquent behaviors; close relationships with parents and parental supervision caused decrease in delinquent behaviors.
Critical Multiculturalism and Democratic Schooling: An Interview with Peter McLaren and Joe Kincheloe

Peter McLaren is a former teacher activist from Toronto, Ontario, where he served as an educational journalist, writing a column entitled "Inner City In­ sight" for the teachers' union. In 1980 he published his classroom diary, Cries from the Corridor, which became a national Canadian best-seller. Since coming to the United States, he has gained a reputation as an internationally acclaimed critical educational theorist. He is the author of numerous books and publications,
The emergence of disfluency in children and the skeleton/root distinction in phonology

We adopt Smith’s ( 1990) framework, in which she defines aspectual into two types, situation types and viewpoint types. The first one is realized by substantive element, while the latter is realized by morphological affixation. She argued that morphological affixation of aspect plays a significant role in defining these two basic meanings. The theoretical background for the analysis is based on the account proposed for early grammars, Tsimpli (1992), which states that aspect is an argument of the verb, in that it occupies E-position. It is argued that the saturation of this argument takes places inside the verb to meet the theta-criterion requirement. This means that aspect is not an independent category which heads its own maximal projection (ASPP), as a result there is no verb raising. Instead, it involves a lexical process which is not subject to any constraint at this stage of acquisition. By assuming that aspect is an argument of the verb, it requires that this element must be charged at some level of representation. However, this analysis seems to account for the similarities in early verbal forms that exhibit aspectual distinction rather than tense. This conclusion is supported by the theoretical consideration on which this analysis is based, in that UG constraints are operative at this stage of acquisition, and morphological status is independent of syntax. So there is no one-to-one correspondence between the realization of a category and its realization as a functional head.
Examination of processing speed deficits in multiple sclerosis using functional magnetic resonance imaging

Abstract Although it is known that processing speed deficits are one of the primary cognitive impairments in multiple sclerosis (MS), the underlying neural mechanisms responsible for impaired processing speed remain undetermined. Using BOLD functional magnetic resonance imaging, the current study compared the brain activity of 16 individuals with MS to 17 healthy controls (HCs) during performance of a processing speed task, a modified version of the Symbol Digit Modalities Task. Although there were no differences in performance accuracy, the MS group was significantly slower than HCs. Although both groups showed similar activation involving the precentral gyrus and occipital cortex, the MS showed significantly less cerebral activity than HCs in bilateral frontal and parietal regions, similar to what has been reported in aging samples during speeded tasks. In the HC group, processing speed was mediated by frontal and parietal regions, as well as the cerebellum and thalamus. In the MS group, processing speed was mediated by insula, thalamus and anterior cingulate. It therefore appears that neural networks involved in processing speed differ between MS and HCs, and our findings are similar to what has been reported in aging, where damage to both white and gray matter is linked to processing speed impairments (JINS, 2009, 15, 383–393).
Incorporation of membrane-anchored flagellin or Escherichia coli heat-labile enterotoxin B subunit enhances the immunogenicity of rabies virus-like particles in mice and dogs

Rabies remains an important worldwide public health threat, so safe, effective, and affordable vaccines are still being sought. Virus-like particle-based vaccines targeting various viral pathogens have been successfully produced, licensed, and commercialized. Here, we designed and constructed two chimeric rabies virus-like particles (cRVLPs) containing rabies virus (RABV) glycoprotein (G), matrix (M) protein, and membrane-anchored flagellin (EVLP-F) or Escherichia coli heat-labile enterotoxin B subunit (EVLP-L) as molecular adjuvants to enhance the immune response against rabies. The immunogenicity and potential of cRVLPs as novel rabies vaccine were evaluated by intramuscular vaccination in mouse and dog models. Mouse studies demonstrated that both EVLP-F and EVLP-L induced faster and larger virus-neutralizing antibodies (VNAs) responses and elicited greater numbers of CD4+ and CD8+ T cells secreting IFN-γ or IL-4 compared with a standard rabies VLP (sRVLP) containing only G and M. Moreover, cRVLPs recruited and/or activated more B cells and dendritic cells in inguinal lymph nodes. EVLP-F induced a strong, specific IgG2a response but not an IgG1 response, suggesting the activation of Th1 class immunity; in contrast, Th2 class immunity was observed with EVLP-L. The significantly enhanced humoral and cellular immune responses induced by cRVLPs provided complete protection against lethal challenge with RABV. Most importantly, dogs vaccinated with EVLP-F or EVLP-L exhibited increased VNA titers in sera and enhanced IFN-γ and IL-4 secretion from peripheral blood mononuclear cells. Taken together, these results illustrate that when incorporated into sRVLP, membrane-anchored flagellin, and heat-labile enterotoxin B subunit possess strong adjuvant activity. EVLP-F and EVLP-L induce significantly enhanced RABV-specific humoral and cellular immune responses in both mouse and dog. Therefore, these cRVLPs may be developed as safe and more efficacious rabies vaccine candidate for animals.
Semi-supervised discriminant analysis based on UDP regularization

We propose a semi-supervised learning algorithm for discriminant analysis, which uses the geometric structure of both labeled and unlabeled samples and perform a manifold regularization on LDA. The labeled data points provide labeling information and the unlabeled data points provide extra geometric structure information of the data, then we learn a labeling function which is as smooth as possible on the data manifold. Experiments on several face databases show the effectiveness of the algorithm.
Atorvastatin does not exhibit antiviral activity against HCV at conventional doses: A pilot clinical trial

Cholesterol biosynthesis is an integral part of HCV RNA replication. Not only does HCV RNA replicate on lipid rafts, but it also requires cholesterol intermediates to replicate. In addition, it has been shown in vitro that several HMG‐CoA reductase inhibitors can decrease HCV RNA replication by ≥ 1 log. Therefore, we designed a clinical trial to evaluate the effect of atorvastatin on HCV RNA levels. In this prospective clinical trial, where patients served as their own control, 10 HCV‐infected patients who required treatment for high cholesterol were given 20 mg atorvastatin per day. Although serum cholesterol and LDL predictably decreased significantly, there was no statistically significant change in week 4 and week 12 HCV RNA levels compared to pretreatment HCV RNA levels by the paired Student t test. It is unclear whether the addition of an HMG‐CoA reductase inhibitor to interferon or a more potent inhibitor of cholesterol biosynthesis may be required to inhibit HCV RNA replication in vivo. In conclusion, atorvastatin, and likely all HMG‐CoA reductase inhibitors, does not inhibit HCV RNA replication in vivo at conventional doses. (HEPATOLOGY 2007;45:895–898.)