Miracle-dz/UniFAR-FTUs huggingface dataset:
Reversal Learning in Humans and Gerbils: Dynamic Control Network Facilitates Learning

Biologically plausible modeling of behavioral reinforcement learning tasks has seen great improvements over the past decades. Less work has been dedicated to tasks involving contingency reversals, i.e., tasks in which the original behavioral goal is reversed one or multiple times. The ability to adjust to such reversals is a key element of behavioral flexibility. Here, we investigate the neural mechanisms underlying contingency-reversal tasks. We first conduct experiments with humans and gerbils to demonstrate memory effects, including multiple reversals in which subjects (humans and animals) show a faster learning rate when a previously learned contingency re-appears. Motivated by recurrent mechanisms of learning and memory for object categories, we propose a network architecture which involves reinforcement learning to steer an orienting system that monitors the success in reward acquisition. We suggest that a model sensory system provides feature representations which are further processed by category-related subnetworks which constitute a neural analog of expert networks. Categories are selected dynamically in a competitive field and predict the expected reward. Learning occurs in sequentialized phases to selectively focus the weight adaptation to synapses in the hierarchical network and modulate their weight changes by a global modulator signal. The orienting subsystem itself learns to bias the competition in the presence of continuous monotonic reward accumulation. In case of sudden changes in the discrepancy of predicted and acquired reward the activated motor category can be switched. We suggest that this subsystem is composed of a hierarchically organized network of dis-inhibitory mechanisms, dubbed a dynamic control network (DCN), which resembles components of the basal ganglia. The DCN selectively activates an expert network, corresponding to the current behavioral strategy. The trace of the accumulated reward is monitored such that large sudden deviations from the monotonicity of its evolution trigger a reset after which another expert subnetwork can be activated—if it has already been established before—or new categories can be recruited and associated with novel behavioral patterns.
An Investigation into Business-to-Business Electronic Commerce Organizations

The issue of information technology (IT) investment evaluation in B2BEC (business-to-business electronic commerce) has generated a lot of interest and discussion among academics and researchers. This research was undertaken to investigate the relationships between the level of IT maturity, the use of IT investment evaluation (IEM) and benefits realisation (BRM) methodologies, and the degree of satisfaction with the adoption of B2BEC in Taiwanese B2BEC organisations. The results indicated that the level of IT maturity was a strong predictor of the use of evaluation methodologies while the use of evaluation methodologies had a significant impact on the degree of satisfaction with the adoption of B2BEC. It was also found that evaluation methodologies had played a mediating role between the level of IT maturity and the degree of satisfaction with the adoption of B2BEC. Managerial implications and future research directions are also provided.
The ideology of the ethical consumption gap

The growth of contemporary capitalism is producing a broad sweep of environmental and social ills, such as environmental degradation, exploitative labor conditions, social and economic inequity, and mental and physical illness. A growing awareness of these significant consequences by an “ethical” consumer segment has catalyzed a field of research dedicated to investigating ethical consumerism. Of particular academic and practitioner focus is the general failure of this ethical consumer segment to “walk their talk”—the ethical consumption attitude–behavior ‘gap’. In this article, we draw on Althusser and Žižek to critically analyze the ideological functioning of the ethical consumption gap. We argue that this focus inadvertently promotes erroneous notions of consumer sovereignty and responsibilization. We conclude with a call to reimagine the gap as a construct that paradoxically preserves—rather than undermines—dominant and destructive consumerist capitalism. We redirect research toward the underlying capitalist structures that predicate and benefit from the gap.
Light-induced cell death of retinal photoreceptors in the absence of p53.

PURPOSE Cell death by apoptosis is essential for normal development and tissue homeostasis, and it is involved also in a variety of pathologic processes. Apoptosis is the final common pathway of photoreceptor cell death in retinal dystrophies and degeneration. So far, little is known about genes regulating apoptosis in the retina. The tumor-suppressor gene product p53 is a potent regulator of apoptosis in numerous systems. However, p53-independent apoptotic pathways also have been described. In this study the authors investigated the role of p53 in the light-induced apoptosis of retinal photoreceptors using mice lacking p53. METHODS Free-moving p53-/- and p53+/+ mice were dark adapted and were exposed to 8,500 or 15,000 lux of diffuse, cool, white fluorescent light for 2 hours. Animals were killed before and immediately after light exposure or at 12 hours in darkness after light exposure. Eyes were enucleated and processed for light and electron microscopy and histochemistry (TdT-dUTP terminal nick-end labeling method). Isolated retinas were subjected to the extraction of total retinal DNA. Electroretinogram (ERG) recordings were performed at all time points. RESULTS Morphologic, biochemical, histochemical, and ERG analysis showed that the retinas of untreated p53-/- mice and wild-type control mice were structurally and functionally indistinguishable. After exposure to diffuse white fluorescent light, light-induced photoreceptor cell death was analyzed and was found to be the same in both groups of mice. CONCLUSIONS These data suggest that light-induced apoptosis of photoreceptors is independent of functional p53.
Model of optical turbulence profile at Cerro Pachon

New measurements of optical turbulence profile at the Cerro Pachon observatory in Chile are analysed jointly with previously published data to model the variations of the intensity and thickness of the ground layer and free atmosphere under a variety of observing conditions. This work is motivated by the need to predict statistically the performance of ground-layer adaptice optics. We find that the ground-layer profile can be represented by a decaying exponent with a scale height of 20-40 m, increasing to 100 m under bad conditions. The zone from 6 to 500 m contributes typically about 61 per cent to the total integral, the latter causing a median seeing of 0.77 arcsec. Turbulence integrals in the ground layer and in free atmosphere vary independently of each other, in 50 per cent of cases they deviate by less than 1.8 times from their respective median values. The existence of periods with low turbulence in the free atmosphere and their importance for adaptive optics is stressed. Ke yw ords: atmospheric effects - instrumentation: adaptive optics - site testing.
MAXIMIN, DISCOUNTING, AND SEPARATING HYPERPLANES

Is Hartwick’s rule a necessary condition for maximin in Solow’s [1974] model? Until recently this has been an open question; this is surprising given the prominence of the model. Cairns and Yang [2000] as well as Withagen, Asheim and Buchholz (this issue) claim that the answer is in the affirmative and claim to provide a formal proof. The latter team argues that the proof by the former is not correct and provides an alternative proof, based on Withagen and Asheim [1998]. Although Cairns and Yang [2000] assert that the methodology of Withagen and Asheim [1998] is “contrived”, our proof in this issue is not in dispute. This settles the question: Hartwick’s rule is necessary in Solow’s model. Nevertheless there is continued controversy. The main point in Cairns’ reply in this issue refers to discounting. In Withagen and Asheim it is assumed (in a very general setting) that an efficient constant utility path is supported by positive utility discount factors
Design and deployment of a hybrid CDN-P2P system for live video streaming: experiences with LiveSky

We present our design and deployment experiences with LiveSky, a commercially deployed hybrid CDN-P2P live streaming system. CDNs and P2P systems are the common techniques used for live streaming, each having its own set of advantages and disadvantages. LiveSky inherits the best of both worlds: the quality control and reliability of a CDN and the inherent scalability of a P2P system. We address several key challenges in the system design and implementation including (a) dynamic resource scaling while guaranteeing stream quality, (b) providing low startup latency, (c) ease of integration with existing CDN infrastructure, and (d) ensuring network-friendliness and upload fairness in the P2P operation. LiveSky has been commercially deployed and used for several large-scale live streaming events serving more than ten million users in China. We evaluate the performance of LiveSky using data from these real-world deployments. Our results indicate that such a hybrid CDN-P2P system provides quality and user performance comparable to a CDN and effectively scales the system capacity when the user volume exceeds the CDN capacity.
A combinatorial formula for non-symmetric Macdonald polynomials

We give a combinatorial formula for the non-symmetric Macdonald polynomials E_{\mu}(x;q,t). The formula generalizes our previous combinatorial interpretation of the integral form symmetric Macdonald polynomials J_{\mu}(x;q,t). We prove the new formula by verifying that it satisfies a recurrence, due to Knop, that characterizes the non-symmetric Macdonald polynomials.
Gas and Dust in the Extremely Red Object ERO J164502+4626.4

We report the first detection of the lowest CO transition in a submillimeter bright galaxy and extremely red object (ERO) at z = 1.44 using the Very Large Array (VLA). The total J = 1-0 line luminosity of ERO J164502+4626.4 is (7 ± 1) × 1010 K km s-1 pc2, which yields a total molecular gas mass of ~6 × 1010 M☉. We also present a map of the 850 μm continuum emission obtained using the Submillimeter Common-User Bolometric Array, from which we infer a far-IR luminosity and dust mass of LFIR ~ 9 × 1012 L☉ and Md ~ 9 × 108 M☉, respectively. We find tentative evidence that the CO and submillimeter dust emission is extended over several tens of kiloparsecs. If confirmed by high-resolution imaging, this implies that ERO J164502+4626.4 is not simply a high-redshift-counterpart of a typical ultra luminous infrared galaxy (ULIRG).
Spurious rejection by cointegration tests incorporating structural change in the cointegrating relationship

In recent research, Leybourne and Newbold have shown commonly employed tests of cointegration to exhibit spurious rejection when applied to independent unit root processes subject to breaks in either level or trend. In the present paper, this research is extended to consider the finite-sample properties of cointegration tests which explicitly incorporate structural change. It is shown that when applied to independent unit root processes subject to regime shifts, cointegration tests permitting structural change in the cointegrating relationship can spuriously reject the null of no cointegration more frequently than the standard tests considered by Leybourne and Newbold.
Deadlock Avoidance Policies for Automated Manufacturing Systems Using Finite State Automata

This chapter considers the problem of deadlock avoidance in flexibly automated manufacturing systems, one of the most prevalent supervisory control problems that challenges the effective deployment of these environments. The problem is addressed through the modeling abstraction of the (sequential) resource allocation system (RAS), and the pursued analysis uses concepts and results from the formal modeling framework of finite state automata (FSA). A notion of optimality is defined through the notion of maximal permissiveness, but the computation of the optimal DAP is shown to be NP-Hard. Hence, the last part of the chapter discusses some approaches that have been developed by the relevant research community in its effort to deal with this negative complexity result.
Performance tradeoffs in dynamic time warping algorithms for isolated word recognition

The technique of dynamic programming for the time registration of a reference and a test pattern has found widespread use in the area of isolated word recognition. Recently, a number of variations on the basic time warping algorithm have been proposed by Sakoe and Chiba, and Rabiner, Rosenberg, and Levinson. These algorithms all assume that the test input is the time pattern of a feature vector from an isolated word whose endpoints are known (at least approximately). The major differences in the methods are the global path constraints (i.e., the region of possible warping paths), the local continuity constraints on the path, and the distance weighting and normalization used to give the overall minimum distance. The purpose of this investigation is to study the effects of such variations on the performance of different dynamic time warping algorithms for a realistic speech database. The performance measures that were used include: speed of operation, memory requirements, and recognition accuracy. The results show that both axis orientation and relative length of the reference and the test patterns are important factors in recognition accuracy. Our results suggest a new approach to dynamic time warping for isolated words in which both the reference and test patterns are linearly warped to a fixed length, and then a simplified dynamic time warping algorithm is used to handle the nonlinear component of the time alignment. Results with this new algorithm show performance comparable to or better than that of all other dynamic time warping algorithms that were studied.
["Novelty" neurons in the frog auditory system].

: Some neurones in the torus semicircularis of paralyzed lake frogs (Rana ridibunda) exhibited strong response habituation to tonal bursts following with interstimuli intervals of 1 to 5 sec. The habituation became less evident with a devrease of the repetition rate or increase of the stimulus intensity. These units revealed the phenomenon of "postzero" habituation. The frequency selectivity of the units exhibited by their responses to the first stimulus presentation was very poor. Usually the habituation occurred within a wide frequency band, although there were some exceptions. Afther the habituation was completed, the unit's response could be elicited by tones of a different frequency. The more distant on the frequency scale the tones were, the more vigorous was the reaction. Some properties of these "novelty" units can be explained by assuming that they are multipolar neurones located in the nucleus magnocellularis of the torus.
The giant pillars of the Carina Nebula

Results are presented from a multi-wavelength study of the giant pillars within the Carina Nebula. Using near-IR data from 2MASS, mid-IR data from MSX, 843 MHz radio continuum maps from the MOST and molecular line and continuum observations from the SEST, we investigate the nature of the pillars and search for evidence of ongoing star formation within them. Photodissociation regions (PDRs) exist across the whole nebula and trace the giant pillars, as well as many ridges, filaments and condensations (A v > 7 mag). Morphological similarities between emission features at 21 μm and 843MHz adjacent to the PDRs, suggests that the molecular material has been carved by the intense stellar winds and UV radiation from the nearby massive stars. In addition, star forming cores are found at the tips of several of the pillars. Using a stellar density distribution, several candidate embedded clusters are also found. One is clearly seen in the 2MASS images and is located within a dense core (G287.84-0.82). A search for massive young stellar objects and compact H II regions using mid-IR colour criteria, reveal twelve candidates across the complex. Grey-body fits to SEDs for four of these objects are suggestive of OB-stars. We find that massive star formation in the Carina Nebula is occurring across the whole complex and confirm it has been continuous over the past 3 Myrs.
CCL2 Chemokine as a Potential Biomarker for Prostate Cancer: A Pilot Study

Purpose Prostate specific antigen is not reliable in diagnosing prostate cancer (PCa), making the identification of novel, precise diagnostic biomarkers important. Since chemokines are associated with more aggressive disease and poor prognosis in diverse malignancies, we aimed to investigate the diagnostic relevance of chemokines in PCa. Materials and Methods Preoperative and early postoperative serum samples were obtained from 39 consecutive PCa patients undergoing radical prostatectomy. Serum from 15 healthy volunteers served as controls. Concentrations of CXCL12, CXCL13, CX3CL1, CCL2, CCL5, and CCL20 were measured in serum by Luminex. The expression activity of CXCR3, CXCR4, CXCR5, CXCR7, CXCL12, CXCL13, CX3CR1, CXCL1, CCR2, CCR5, CCR6, CCR7, CCL2, and CCL5 mRNA was assessed in tumor and adjacent normal tissue of prostatectomy specimens by quantitative real-time polymerase chain reaction. The associations of these chemokines with clinical and histological parameters were tested. Results The gene expression activity of CCL2 and CCR6 was significantly higher in tumor tissue compared to adjacent normal tissue. CCL2 was also significantly higher in the blood samples of PCa patients, compared to controls. CCL5, CCL20, and CX3CL1 were lower in patient serum, compared to controls. CCR2 tissue mRNA was negatively correlated with the Gleason score and grading. Conclusion Chemokines are significantly modified during tumorigenesis of PCa, and CCL2 is a promising diagnostic biomarker.
Are Coups Really Contagious? An Extreme Bounds Analysis of Political Diffusion

Protests and democratic transitions tend to spread cross-nationally. Is this true of all political events? We argue that the mechanisms underlying the diffusion of mass-participation events are unlikely to support the spread of elite-led violence, particularly coups. Further, past findings of coup contagion employed empirical techniques unable to distinguish clustering, common shocks, and actual diffusion. To investigate which events diffuse and where, we combine modern spatial dependence models with extreme bounds analysis (EBA). EBA allows for numerous modeling alternatives, including diffusion timing and the controls, and calculates the distribution of estimates across all combinations of these choices. We also examine various diffusion pathways, such as contagion among trade partners. Results from nearly 1.2 million models clearly undercut coup contagion. In comparison, we confirm that more mass-driven political events robustly spread cross-nationally. Our findings contribute to studies of political conflict and contagion, while introducing EBA as an effective tool for diffusion scholars.
The Shear Bond Strength of Porcelain Laminate to Prepared and Unprepared Anterior Teeth

Statement of the Problem: Porcelain laminate veneer is an esthetic restoration used as an alternative to full veneer crowns and requires minimal tooth preparation. In restoration with porcelain laminate veneers, both the longevity of the laminate and conservation of the sound tooth structure are imperative. Purpose: The present study aimed to investigate the shear bond strength of porcelain laminates to prepared- and unprepared- anterior teeth in order to compare their longevity and success rate. Materials and Method: Thirty extracted maxillary central incisors were randomly divided into 3 groups regarding their preparation methods. The preparation methods were full-preparation in group A, full-preparation and finishing with fine diamond bur in group B, and no-preparation, only grinding with diamond bur in group C. After conditioning the teeth, ceramic veneers (IP S e.max) were silanated and then cemented with DuoLink luting cement. The shear bond strength was measured for each group and failure mode was determined by stereomicroscopic examination. Results: Group C exhibited the highest shear bond strength. The shear bond strength was significantly different between groups C and B (p< 0.05). However, the difference between group A and C was insignificant, as was the difference between group A and B (p> 0.05). Adhesion failure mode was found to be more common than the cohesive mode. Conclusion: Regarding the shear bond strength of unprepared anterior teeth to porcelain laminate veneers yielded by this study, no-preparation veneers might be used when the enamel is affected by wearing, trauma, or abrasion. It can also be used in patients who refuse the treatments which involve tooth reduction and preparation.
Closed-Form Expression for Focal Lengths from the Fundamental Matrix

We describe an algorithm for decomposing a fundamental matrix computed from point correspondences over two images into the focal lengths of the two images and the camera motion parameters in a closed-form expression. Our algorithm is based on the decomposability condition of the essential matrix expressed in terms of its scalar invariants. We give a complete analysis for degenerate camera con gurations. We also describe an algorithm for computing a single focal length in the degenerate case and analyze the indeterminacy condition.
Effects of vehicle-vehicle/roadside-vehicle communication on adaptive cruise controlled highway systems

We study the effect of vehicle vehicle/vehicle-roadside communication on the performance of adaptive cruise control (ACC) systems. Two simulation works are presented One is a single ACC vehicle simulation using MATLAB/SIMULINK. A cut-in scenario and a braking scenario are tested Communication greatly saves control effort in the former scenario, while has little effect in the latter. The other work simulates ACC controlled highway merging with SHIFT language. The results show beneficial effects of communication in terms of braking effort, waiting-to-merge queue length, and main lane traffic shock wave caused by merging.
Hochschild homology and cohomology of l^1 (Z^k+)

Building on the recent determination of the simplicial cohomology groups of the convolution algebra l 1 (Z k) [Gourdeau, Lykova, White, 2005] we investigate what can be said for cohomology of this algebra with more general symmetric coefficients. Our approach leads us to a discussion of Harrison homology and cohomology in the context of Banach algebras, and a development of some of its basic features. As an application of our techniques we reprove some known results on second-degree cohomology.