Miracle-dz/UniFAR-FTUs huggingface dataset:
Weak error analysis of tau-leaping methods for multi-scale stochastic chemical kinetic systems

A chemical reaction network is a chemical system involving multiple reactions and chemical species. The simplest stochastic models of such networks treat the system as a continuous time Markov chain with the state being the number of molecules of each species and with reactions modeled as possible transitions of the chain. For such models, there is typically a wide variation in temporal and other quantitative scales. In this multi-scale setting it is typically an extremely dicult task to perform approximations, such as Langevin approximations or law of large number type arguments, to simplify a system. Therefore, numerical methods oftentimes are the only reasonable means by which such models can be understood in real time. In this paper we provide a general framework for understanding the weak error of numerical approximation techniques in the multi-scale setting. We quantify how the error of three dierent methods depends upon both the natural scalings within a given system, and with the step-size of the numerical method. Further, we introduce a new algorithm in this setting, the weak trapezoidal algorithm, which was developed originally as an approximate method for diusion processes, and prove that the leading order of the error process scales with the square of the time discretization, making it the rst second order method in this setting.
Real Exchange Rates and Optimum Currency Areas: Evidence from Developed Economies

In this paper, the authors link real exchange rates and optimum currency area criteria. The authors examine the hypothesis that countries not fulfilling optimum currency area criteria in full will tend to have volatile bilateral real exchange rate. The authors find that, based on a study of data from developed economies from the 1990s, optimum currency criteria (such as trade integration, asymmetry of shocks, openness) help explain bilateral real exchange-rate variation.
Civil society, human security, and the politics of peace-building in victor’s peace Sri Lanka (2009-2012)

This thesis aims to expand scholarship on civil society and peace-building through exploration of civil society’s experiences, perspectives, and practices in relation to the politics of peace-building and human (in)security in instances of victor’s peace, using post-war Sri Lanka as case study. It adopts Human Security as an analytical approach calling attention to insecurities operating on and through Sri Lankans but also the nature of power dynamics underlying these insecurities based on the subjective and political nature of ‘peace’ itself. The thesis contributes conceptually and empirically to knowledge of the operation of victor’s peace and its implications for civil society in peace-building. This thesis’s central contention is that acts of securitization and governmentality carried out by Sri Lanka’s central governmental elite within and enabled by the victor’s peace have constricted spaces for civil society to articulate alternatives or engage in critical dialogue within the political process fostered under the victor’s peace. This study, thus, questions romanticized notions of the potentiality of ‘local’ resistances to shift structural inequalities and power asymmetries in victor’s peace. At a disciplinary level, the thesis also deepens knowledge, first, on civil society as complex and contested sphere. It argues that to conceptualize civil society as homogenous or inherently altruistic risks drastically oversimplifying its highly diffuse nature and politics within the sector in which certain actors may benefit within the victor’s peace and engage in ‘peace’-building activities in order to both capitalise on those benefits and sustain the victor’s peace. Second, the thesis addresses the nexus between civil society and peace-building, and specifically the politics of peace-building, in the victor’s peace. In not being constrained by negotiated peace settlement it asserts that, as in Sri Lanka, instances of victor’s peace can quickly transition into repressive environments. Here it is unlikely that civil society, despite innovative methods of exercising agency, can significantly alter the trajectories of the ‘peace’, and further that those civil society actors that support the victor’s peace may seek to exploit the benefits they gain from it at the expense of the human security of others. Finally, the thesis asserts that, ultimately, Human Security’s utility may lie not as political agenda that validates external intervention based on a ‘responsibility’ to intervene, but as a conceptual framework for developing deeper understandings of the nature of (in)security and factors driving (in)security at multiple levels of analysis within different articulations or ‘types’ of peace.
Financial Frictions and the Persistence of History

How do movements in the distribution of income and wealth affect the macroeconomy? We create two economies where the only difference between them lies in the initial distribution of economic resources and the degree of frictions in financial markets. Generally, these economies eventually reach the same (or very similar) stationary equilibria in terms of aggregate variables--e.g. capital stock and output. In this sense, financial frictions and wealth distribution have little macroeconomic impact on the stationary equilibria. Here we map out the entire transition dynamics and answer the following questions: (i) Do financial frictions slow down the economy's progression toward the stationary equilibria? (ii) Does inequality affect the speed of convergence to the stationary equilibria? and (iii) If economic resources are initially misallocated (e.g. entrepreneurs not having any resources), is the speed of convergence to the stationary equilibria significantly lower? We find that financial frictions and initial wealth distribution have significant and persistent effects on the transitional dynamics of the aggregate variables
Integrating Muslim Customer Perceived Value, Satisfaction, Loyalty and Retention in the Tourism Indu

In recent years, customer value has been the favorable theme for numerous tourism studies and reports. However, although Muslims make up one of the largest tourist markets in the world, perceived value of tourism offering oriented toward this market has not been clearly defined. Furthermore, there is a lack of systematic empirical evidence regarding the effects of Muslim Customer Perceived Value (MCPV) on consumer satisfaction, customer loyalty and customer retention. Therefore, the purpose of this paper is to identify the MCPV dimensions, to examine the interrelationships between MCPV, customer satisfaction, customer loyalty and Muslim customer retention, and to develop and test a conceptual model of the consequences of MCPV in the tourism industry. Moreover, 13 hypotheses were developed and tested using a sample of 221 Muslim tourists. Exploratory and confirmatory factor analysis were used to test the validity of the measures, while the structural equation modeling has been used in hypotheses testing. The strength of the relationship between the constructs indicates that features of the suggested MCPV model are crucial to achieving Muslim customer retention in the tourism industry. Findings also suggest that the availability of the suggested Islamic attributes value, along with conventional value dimensions, could satisfy Muslim tourists when they buy a tourism package. Copyright © 2013 John Wiley & Sons, Ltd.
Testing for Market Imperfections: Participation in Land & Labor Contracts in Turkish Agriculture

A remarkable degree of self-sufficiency is a distinguishing feature of the typical Third World family farm. However, many family farms deviate from this pattern and engage in transactions involving land and labor. The question is why some households use land and labor markets while others do not. We posit that markets may function imperfectly and discourage households from participation. We model imperfections in terms of transaction costs which drive a household-specific wedge between sales and purchase prices of factors. When the shadow price of a factor falls inside this range, the household has no incentive to adjust that particular margin. The frictionless model emerges as a limiting case in which sales, purchase and shadow prices are equal. The empirical work is based on data from a 1973 nationwide survey in Turkey. The subsample of owner-cultivators is sorted into a 3x3 table according to the adjustments that took place on the land margin (lease out, do not participate, lease in), and the labor margin (hire out, do not participate, hire in), and the determinants of the observed pattern of adjustments are investigated. The estimating equations are obtained from the theoretical model by treating the shadow, sales, and purchase prices as latent variables and expressing them as linear functions of observables. We use an unrestricted bivariate ordered probit specification and estimate the parameters using maximum likelihood methods. This procedure uncovers the links between observables and the transaction costs faced by each household, making it possible to confront transactions cost theory with real world data.
The social sciences and the web: From ‘Lurking’ to interdisciplinary ‘Big Data’ research

‘Big data’ is an area of growing research interest within sociology and numerous other disciplines. The rapid development of social media platforms and other web resources offer a vast and readily accessible repository of data associated with participants’ activities, attitudes and personal information on a scale and depth that would have previously been difficult to access without substantial resources. However, as well as offering opportunities to social researchers, this medium also presents a significant range of challenges. Ethical issues are one much debated area where social scientists are having to reassess their longstanding modus operandi, given questions regarding access to personal data and ambiguities regarding its status and legitimate usage. In addition, the scale of data accessible and the possible skills required to collect and analyse it is also a critical issue, and is an area that, arguably, has received lesser attention. In its infancy, online research could be fairly rudimentary, employing simple techniques to gather information from weblogs, forums and so on. However, the possibilities now presented by large-scale social media platforms has created the potential for more sophisticated research that often requires specialist technical expertise, involving collaborative work by computer and social scientists working together. This is a scenario that raises its own concerns, not least in terms of forging areas of shared understanding between these disparate disciplines sufficient to facilitate such projects. This article addresses such issues, providing a reflection on the theoretical and practical experience of engaging in online research, from fledgling involvement to embarking on a current collaborative interdisciplinary project. The aim is to provide some insights to other social scientists with respect to some of the potential advantages and pitfalls of web research, while a flavour of the current project, exploring Scottish Referendum and UK General Election related Twitter data, is also presented.
Memory T Cells in Transplantation: Generation, Function, and Potential Role in Rejection

The adaptive immune system is endowed with long‐lived memory to recall previous antigen encounters and respond more effectively to them. Memory immune responses are mediated by antigen‐specific memory T lymphocytes that exhibit enhanced function compared with naïve T cells that have never encountered antigen. While the generation of memory T cells specific for pathogens is beneficial in providing protective immunity, memory T cells specific for alloantigens can be deleterious to the recipient of a transplanted organ. In graft rejection, memory T cells mediate accelerated, ‘second‐set’ rejection and their presence has been associated with increased propensity for early rejection. Recent findings have demonstrated that alloreactive memory T cells can be generated via exposure to alloantigens, as well as stimuli that are cross‐reactive with alloantigens, and are therefore likely present in ‘naïve’ individuals. This review focuses on the characteristics of memory T cells which make them of special interest to the transplant community, including differential activation requirements, broad homing properties, and resistance to tolerance induction. The multiple ways in which memory T cells can contribute to early and late graft rejection are discussed, as well as potential targets for combating alloreactive memory to be considered in the future design of tolerance induction strategies.
High Blood Pressure during Pregnancy is not a Protective Factor for Preterm Infants with Very Low Birth Weight. A Case-Control Study

Abstract Objective To evaluate whether the presence of maternal blood pressure reduces the risks of morbidity, perinatal mortality and morbidity at 24 months of age in very low birth weight infants (VLBWIs) compared with a control group. Methods A retrospective, observational, case-control study. Total 49 VLBWIs were allocated to the study group, called the maternal arterial hypertension group (AHG), and matched with 44 in the control group (CG). The infants were assessed during hospitalization and at 12 and 24 months corrected age at a specialized clinic. For the assessment of growth, the World Health Organization (WHO) Anthro software (Geneva, 2006) was used, and for the psychomotor assessment, the Denver II test was used. Results In relation to the antenatal variables, the infants of the AHG had more centralized circulation assessed by Doppler, received more corticosteroids and magnesium sulfate, and were born by cesarean section more frequently. In terms of the postnatal and in-hospital outcomes, the AHG had a higher gestational age at birth (30.7 versus 29.6 weeks) and a lower frequency of 5-minute Apgar scores of less than 7 (26.5% versus 52.3%). The CG had a higher rate of pulmonary dysplasia (30.2% versus 8.3%). There were no differences in terms of hospital mortality, complications, somatic growth and functional problems at 24 months of corrected age. Conclusion The presence of maternal hypertension, especially preeclampsia, was not a protective factor against morbidity, mortality and evolution in VLBWIs aged up to 24 months. Therefore, the clinical practice should be focused on prolonging the pregnancy for as long as possible in these conditions as well.
Disruption of an oligomeric interface prevents allosteric inhibition of Escherichia coli class Ia ribonucleotide reductase

Ribonucleotide reductases (RNRs) convert ribonucleotides to deoxynucleotides, a process essential for DNA biosynthesis and repair. Class Ia RNRs require two dimeric subunits for activity: an α2 subunit that houses the active site and allosteric regulatory sites and a β2 subunit that houses the diferric tyrosyl radical cofactor. Ribonucleotide reduction requires that both subunits form a compact α2β2 state allowing for radical transfer from β2 to α2. RNR activity is regulated allosterically by dATP, which inhibits RNR, and by ATP, which restores activity. For the well-studied Escherichia coli class Ia RNR, dATP binding to an allosteric site on α promotes formation of an α4β4 ring-like state. Here, we investigate whether the α4β4 formation causes or results from RNR inhibition. We demonstrate that substitutions at the α–β interface (S37D/S39A-α2, S39R-α2, S39F-α2, E42K-α2, or L43Q-α2) that disrupt the α4β4 oligomer abrogate dATP-mediated inhibition, consistent with the idea that α4β4 formation is required for dATP's allosteric inhibition of RNR. Our results further reveal that the α–β interface in the inhibited state is highly sensitive to manipulation, with a single substitution interfering with complex formation. We also discover that residues at the α–β interface whose substitution has previously been shown to cause a mutator phenotype in Escherichia coli (i.e. S39F-α2 or E42K-α2) are impaired only in their activity regulation, thus linking this phenotype with the inability to allosterically down-regulate RNR. Whereas the cytotoxicity of RNR inhibition is well-established, these data emphasize the importance of down-regulation of RNR activity.
The efficacy of a working memory training in substance use patients: A randomized double-blind placebo-controlled clinical trial

ABSTRACT Introduction: Substance use disorder patients show impairments in working memory (WM) functioning. Previous findings indicate that a WM training results in improvements of working memory capacity (WMC) and in decreased clinical symptoms in a range of mental disorders, including alcohol use disorder. Method: The aim of the current study is to investigate the efficacy of a 24-session WM training in addition to treatment as usual on craving, WMC, substance use, impulsivity, attention bias, and psychopathology using a randomized double-blind placebo-controlled trial. Inpatients (n = 180) diagnosed with an alcohol, cocaine, or cannabis use disorder were included. Results: Although the WM training resulted in better scores on the trained tasks in both groups, the placebo training resulted in a better or equal WMC compared to the experimental training, as measured with two nontrained transfer tasks. The WM training had no effect on craving, substance use, impulsivity, attention bias, and psychopathology. Conclusion: Overall, we did not find evidence for the efficacy of WM training on WMC or clinical symptoms as compared to a placebo training in a population of substance use disorder patients. Future research needs to investigate further whether WMC is an important factor that is associated with substance-abuse-related behavior, and whether working memory training could be useful in substance use disorders.
Could It Be Snowing Microbes on Enceladus? Assessing Conditions in Its Plume and Implications for Future Missions

Abstract We analyzed Cassini Imaging Science Subsystem (ISS) images of the plume of Enceladus to derive particle number densities for the purpose of comparing our results with those obtained from other Cassini instrument investigations. Initial discrepancies in the results from different instruments, as large as factors of 10–20, can be reduced to ∼2 to 3 by accounting for the different times and geometries at which measurements were taken. We estimate the average daily ice production rate, between 2006 and 2010, to be 29 ± 7 kg/s, and a solid-to-vapor ratio, S/V > 0.06. At 50 km altitude, the plume's peak optical depth during the same time period was τ ∼ 10−3; by 2015, it was ∼10−4. Our inferred differential size distribution at 50 km altitude has an exponent q = 3. We estimate the average geothermal flux into the sea beneath Enceladus' south polar terrain to be comparable to that of the average Atlantic, of order 0.1 W/m2. Should microbes be present on Enceladus, concentrations at hydrothermal vents on Enceladus could be comparable to those on Earth, ∼105 cells/mL. We suggest the well-known process of bubble scrubbing as a means by which oceanic organic matter and microbes may be found in the plume in significantly enhanced concentrations: for the latter, as high as 107 cells/mL, yielding as many as 103 cells on a 0.04 m2 collector in a single 50 km altitude transect of the plume. Mission design can increase these numbers considerably. A lander mission, for example, catching falling plume particles on the same collector, could net, over 100 Enceladus days without bubble scrubbing, at least 105 cells; and, if bubble scrubbing is at work, up to 108 cells. Key Words: Enceladus—Microbe—Organic matter—Life detection. Astrobiology 17, 876–901.
Mycobacterium avium infection in HIV‐1‐infected subjects increases monokine secretion and is associated with enhanced viral load and diminished immune response to viral antigens

The complex interaction between HIV‐1 infection and Mycobacterium avium was studied. Viral burden was assessed, as well as immune response to HIV‐1 in the context of Myco. avium infections. We also examined serum cytokine levels and cytokine release by blood mononuclear cells in HIV‐1‐infected subjects, infected or not with Myco. avium. Undetectable serum levels of IL‐1, tumour necrosis factor‐alpha(TNF‐α) and IL‐6 were found in normal controls and in groups I, II and III of HIV‐1‐infecled subjects. Moderate levels of TNF‐α, IL‐1 and IL‐6 were found in the sera of group IV patients. When group IV was subdivided into subjects with and without Myco. avium infections, subjects with Myco. avium infections were shown to have higher serum levels of TNF‐α, IL‐Iβ and IL‐6 than those with other infections. Blood mononuclear cells from controls and HIV subjects were stimulated with bacterial lipopolysaccharide, and cytokine levels assessed. Cells from group II patients were shown to secrete normal levels of TNF‐α and IL‐6, and lower levels of IL‐1β group III subjects released higher levels of IL‐6. Patients in group IV had blood cells that released elevated levels of lL‐6 and TNF‐α, and lower levels of IL‐β Group IV subjects with Myco. avium infections had blood cells that released higher levels of TNF‐α, IL‐6 and IL‐1 than group IV subjects with other infections. Assessment of viral burden in cells of HIV‐1‐infected subjects revealed that Myco. avium‐infected subjects had a higher level of virus burden and a lower level of lymphoproliferative response to an inactivated gp120‐depleted HIV‐1 antigen than AIDS subjects with other infections. These data suggest that Myco. avium infections in HIV‐1‐infected subjects hasten the progression of viral disease, enhance cytokine release and contribute to the anergy to viral antigens.
The Experience of Younger Adults Following Myocardial Infarction

The aim of this study was to elucidate the meaning of the experience of younger people (< 55 years) during their first year following a myocardial infarction. We analyzed 17 interviews using a phenomenological–hermeneutic method. The core theme and central phenomenon was the everyday fight to redress the balance in life, which encompassed an existential, physical, and emotional battle to regain a foothold in daily life. The aftermath of a life-threatening event involved a process of transition while at the same time creating a new meaning in life. Lack of energy and its impact on the complex interplay of midlife combined with unreasonable demands from employers and health care professionals seemed to color the experience of the informants. The knowledge gained in this study can constitute a valuable contribution to overall quality assurance in nursing care and the development of nursing interventions for the cardiac rehabilitation of younger patients.
A generalization of the Kostant-Macdonald identity.

Let X be a smooth projective variety admitting an algebraic vector field V with exactly one zero and a holomorphic C(*)-action lambda so that the condition dlambda(t). V = t(p)V holds for all t in C(*). The purpose of this note is to report on a product formula for the Poincaré polynomial of X which specializes to the classical identity [Formula: see text] when X is the flag variety of a semisimple complex Lie group. A surprising corollary is that the second Betti number of such an X is the multiplicity of largest weight of the linear C(*)-action on the tangent space of X at the sink of lambda. We discuss several examples, including a construction of the rational Fano 3-folds A'(22) and B(5) which is due to Konarski [Konarski, J. (1989) in C.M.S. Conference Proceedings, ed. Russell, P. (Am. Math. Soc., Providence, RI), in press].