Miracle-dz/UniFAR-FTUs huggingface dataset:
An Imperfect Dopaminergic Error Signal Can Drive Temporal-Difference Learning

An open problem in the field of computational neuroscience is how to link synaptic plasticity to system-level learning. A promising framework in this context is temporal-difference (TD) learning. Experimental evidence that supports the hypothesis that the mammalian brain performs temporal-difference learning includes the resemblance of the phasic activity of the midbrain dopaminergic neurons to the TD error and the discovery that cortico-striatal synaptic plasticity is modulated by dopamine. However, as the phasic dopaminergic signal does not reproduce all the properties of the theoretical TD error, it is unclear whether it is capable of driving behavior adaptation in complex tasks. Here, we present a spiking temporal-difference learning model based on the actor-critic architecture. The model dynamically generates a dopaminergic signal with realistic firing rates and exploits this signal to modulate the plasticity of synapses as a third factor. The predictions of our proposed plasticity dynamics are in good agreement with experimental results with respect to dopamine, pre- and post-synaptic activity. An analytical mapping from the parameters of our proposed plasticity dynamics to those of the classical discrete-time TD algorithm reveals that the biological constraints of the dopaminergic signal entail a modified TD algorithm with self-adapting learning parameters and an adapting offset. We show that the neuronal network is able to learn a task with sparse positive rewards as fast as the corresponding classical discrete-time TD algorithm. However, the performance of the neuronal network is impaired with respect to the traditional algorithm on a task with both positive and negative rewards and breaks down entirely on a task with purely negative rewards. Our model demonstrates that the asymmetry of a realistic dopaminergic signal enables TD learning when learning is driven by positive rewards but not when driven by negative rewards.
Chlorophyll-a Estimation Around the Antarctica Peninsula Using Satellite Algorithms: Hints from Field Water Leaving Reflectance

Ocean color remote sensing significantly contributes to our understanding of phytoplankton distribution and abundance and primary productivity in the Southern Ocean (SO). However, the current SO in situ optical database is still insufficient and unevenly distributed. This limits the ability to produce robust and accurate measurements of satellite-based chlorophyll. Based on data collected on cruises around the Antarctica Peninsula (AP) on January 2014 and 2016, this research intends to enhance our knowledge of SO water and atmospheric optical characteristics and address satellite algorithm deficiency of ocean color products. We collected high resolution in situ water leaving reflectance (±1 nm band resolution), simultaneous in situ chlorophyll-a concentrations and satellite (MODIS and VIIRS) water leaving reflectance. Field samples show that clouds have a great impact on the visible green bands and are difficult to detect because NASA protocols apply the NIR band as a cloud contamination threshold. When compared to global case I water, water around the AP has lower water leaving reflectance and a narrower blue-green band ratio, which explains chlorophyll-a underestimation in high chlorophyll-a regions and overestimation in low chlorophyll-a regions. VIIRS shows higher spatial coverage and detection accuracy than MODIS. After coefficient improvement, VIIRS is able to predict chlorophyll a with 53% accuracy.
University of Mannheim Corporate Governance and the Financing of Investment for Structural Change 1 1 The Corporation as a Financial Institution

Discussions of financial systems tend to identify banks (financial intermediaries) and markets as the major institutions determining the workings of the financial system as it guides the flow of funds from the household sector to the production sector of the economy. The contrast of "bankdominated" and "market-oriented" financial systems has for a long time occupied centre stage of the literature on financial institutions. The present paper leaves this concern with banks and markets aside and instead proposes to focus attention on the industrial corporation as a financial institution in its own right. Corporate managers have significant discretion in the use of corporate funds. As these funds are used, they fulfil a financing role of their own.
Visual signs and symptoms of multiple system atrophy

Multiple system atrophy (MSA) is a rare movement disorder and a member of the ‘parkinsonian syndromes’, which also include Parkinson's disease (PD), progressive supranuclear palsy (PSP), dementia with Lewy bodies (DLB) and corticobasal degeneration (CBD). Multiple system atrophy is a complex syndrome, in which patients exhibit a variety of signs and symptoms, including parkinsonism, ataxia and autonomic dysfunction. It can be difficult to separate MSA from the other parkinsonian syndromes but if ocular signs and symptoms are present, they may aid differential diagnosis. Typical ocular features of MSA include blepharospasm, excessive square‐wave jerks, mild to moderate hypometria of saccades, impaired vestibular‐ocular reflex (VOR), nystagmus and impaired event‐related evoked potentials. Less typical features include slowing of saccadic eye movements, the presence of vertical gaze palsy, visual hallucinations and an impaired electroretinogram (ERG). Aspects of primary vision such as visual acuity, colour vision or visual fields are usually unaffected. Management of the disease to deal with problems of walking, movement, daily tasks and speech problems is important in MSA. Optometrists can work in collaboration with the patient and health‐care providers to identify and manage the patient's visual deficits. A more specific role for the optometrist is to correct vision to prevent falls and to monitor the anterior eye to prevent dry eye and control blepharospasm.
utomatic segmentation of relevant textures in agricultural images

One important issue emerging strongly in agriculture is related with the automatization of tasks, where the optical sensors play an important role. They provide images that must be conveniently processed. The most relevant image processing procedures require the identification of green plants, in our experiments they come from barley and corn crops including weeds, so that some types of action can be carried out, including site-specific treatments with chemical products or mechanical manipulations. Also the identification of textures belonging to the soil could be useful to know some variables, such as humidity, smoothness or any others. Finally, from the point of view of the autonomous robot navigation, where the robot is equipped with the imaging system, some times it is convenient to know not only the soil information and the plants growing in the soil but also additional information supplied by global references based on specific areas. This implies that the images to be processed contain textures of three main types to be identified: green plants, soil and sky if any. This paper proposes a new automatic approach for segmenting these main textures and also to refine the identification of sub-textures inside the main ones. Concerning the green identification, we propose a new approach that exploits the performance of existing strategies by combining them. The combination takes into account the relevance of the information provided by each strategy based on the intensity variability. This makes an important contribution. The combination of thresholding approaches, for segmenting the soil and the sky, makes the second contribution; finally the adjusting of the supervised fuzzy clustering approach for identifying sub-textures
Nucleolar Protein Trafficking in Response to HIV-1 Tat: Rewiring the Nucleolus

The trans-activator Tat protein is a viral regulatory protein essential for HIV-1 replication. Tat trafficks to the nucleoplasm and the nucleolus. The nucleolus, a highly dynamic and structured membrane-less sub-nuclear compartment, is the site of rRNA and ribosome biogenesis and is involved in numerous cellular functions including transcriptional regulation, cell cycle control and viral infection. Importantly, transient nucleolar trafficking of both Tat and HIV-1 viral transcripts are critical in HIV-1 replication, however, the role(s) of the nucleolus in HIV-1 replication remains unclear. To better understand how the interaction of Tat with the nucleolar machinery contributes to HIV-1 pathogenesis, we investigated the quantitative changes in the composition of the nucleolar proteome of Jurkat T-cells stably expressing HIV-1 Tat fused to a TAP tag. Using an organellar proteomic approach based on mass spectrometry, coupled with Stable Isotope Labelling in Cell culture (SILAC), we quantified 520 proteins, including 49 proteins showing significant changes in abundance in Jurkat T-cell nucleolus upon Tat expression. Numerous proteins exhibiting a fold change were well characterised Tat interactors and/or known to be critical for HIV-1 replication. This suggests that the spatial control and subcellular compartimentaliation of these cellular cofactors by Tat provide an additional layer of control for regulating cellular machinery involved in HIV-1 pathogenesis. Pathway analysis and network reconstruction revealed that Tat expression specifically resulted in the nucleolar enrichment of proteins collectively participating in ribosomal biogenesis, protein homeostasis, metabolic pathways including glycolytic, pentose phosphate, nucleotides and amino acids biosynthetic pathways, stress response, T-cell signaling pathways and genome integrity. We present here the first differential profiling of the nucleolar proteome of T-cells expressing HIV-1 Tat. We discuss how these proteins collectively participate in interconnected networks converging to adapt the nucleolus dynamic activities, which favor host biosynthetic activities and may contribute to create a cellular environment supporting robust HIV-1 production.
Micromachined inertial sensors

This paper presents a review of silicon micromachined accelerometers and gyroscopes. Following a brief introduction to their operating principles and specifications, various device structures, fabrication, technologies, device designs, packaging, and interface electronics issues, along with the present status in the commercialization of micromachined inertial sensors, are discussed. Inertial sensors have seen a steady improvement in their performance, and today, microaccelerometers can resolve accelerations in the micro-g range, while the performance of gyroscopes has improved by a factor of 10/spl times/ every two years during the past eight years. This impressive drive to higher performance, lower cost, greater functionality, higher levels of integration, and higher volume will continue as new fabrication, circuit, and packaging techniques are developed to meet the ever increasing demand for inertial sensors.
Mental Illness Stigma and Community Integration: Linking Perceived Experiences with Reported Behavior

Mental Illness Stigma and Community Integration: Linking Perceived Experiences with Reported Behavior by Lauren Gonzales Advisor: Philip T. Yanos This study examines the relationship between individual and neighborhood characteristics, stigmatizing experiences, and measures of community integration among individuals with mental illness. Surveys were administered to two samples: 608 community member participants and 343 participants with mental health diagnoses. Participants in both samples were recruited from 3 community sites in the New York City metropolitan area: East/Central Harlem in Manhattan, Crown Heights/East Flatbush in Brooklyn, and Yonkers and Mt. Vernon in Southern Westchester. Negative symptoms and perceived level of community microaggressions were strong predictors of community integration for participants with mental illness. Prior contact with mental illness predicted less stigmatizing attitudes, and suburban values predicted more perpetrated microaggression behavior reported by community members. Contrary to hypotheses, no significant relationship was found between community memberreported and psychiatric sample-perceived stigma. Findings suggest that the community participation of individuals with severe mental illness is multifaceted and is best evaluated as a combination of both individual and neighborhood characteristics.
The Financing of Innovation: Learning and Stopping

We consider the financing of a research project under uncertainty about the time of completion and the probability of eventual success. We distinguish between two financing modes, namely relationship financing, where the allocation decision of the entrepreneur is observable, and arm's-length financing, where it is unobservable. We find that equilibrium funding stops altogether too early relative to the efficient stopping time in both financing modes. The rate at which funding is released becomes tighter over time under relationship financing, and looser under arm's-length financing. The tradeoff in the choice of financing modes is between lack of commitment with relationship financing and information rents with arm's-length financing.
The operational impact of QuikSCAT winds at the National Oceanic and Atmospheric Administration Ocean Prediction Center

The primary responsibility of National Oceanic and Atmospheric Administration's (NOAA) Ocean Prediction Center (OPC) is to issue marine warnings and forecasts of winds and seas for the high seas and offshore waters of the Atlantic and Pacific Oceans. This covers vast open ocean areas from the subtropics to the near arctic. Accurate and timely surface data are necessary to make these warning decisions. Although conventional observations from buoys and ships of opportunity are very useful to marine forecasters, their distribution is sparse, often being limited to trade routes or continental waters. Over the past twelve years, forecasters have come to rely more and more on remotely sensed data. Special sensor microwave/imager (SSM/I) winds have been used to help fill in the gaps between conventional observations. However the SSM/I retrievals are not available in areas of liquid cloud and precipitation and are restricted to the lowest wind warning category (GALE). Wind retrievals from various scatterometers flown onboard satellites have been available to OPC forecasters over the last ten years and were used with some success. QuikSCAT winds are now fully integrated into OPC operations and have proven to be invaluable. The wide swath width and all weather capabilities have enabled OPC forecasters to use these winds routinely to determine the extent and magnitude of strong winds, the location of fronts and pressure systems, and wind gradients associated with oceanographic thermal features. Since the inclusion of QuikSCAT into OPC operations the marine forecaster's ability to accurately assess wind conditions over the open oceans has never been better
The Association between IgG4 Antibodies to Dietary Factors, Islet Autoimmunity and Type 1 Diabetes: The Diabetes Autoimmunity Study in the Young

Background Infant dietary exposures have been linked to type 1 diabetes (T1D) development. IgG4 antibody responses to food antigens are associated with food intolerances but have not been explored prospectively in the period preceding T1D. Methods Using a case-cohort design, IgG4 antibodies to ß-lactoglobulin, gluten, and ovalbumin were measured in plasma collected annually from 260 DAISY participants. Of those, 77 developed islet autoimmunity (IA), defined as positive for either insulin, GAD65 or IA-2 autoantibodies on two consecutive visits, and 22 developed T1D. Results In mixed model analysis adjusting for HLA-DR status, T1D family history, age and ethnicity, higher ß-lactoglobulin IgG4 concentrations were associated with shorter breastfeeding duration (beta = −0.03, 95% Confidence Interval: −0.05, −0.006) and earlier first cow’s milk exposure (beta = −0.04, 95% Confidence Interval: −0.08, 0.00). Higher gluten IgG4 was associated with older age at gluten introduction (beta = 0.06, 95% Confidence Interval: 0.00, 0.13). In proportional hazards analysis adjusting for HLA-DR status, T1D family history and ethnicity, IgG4 against individual or multiple dietary antigens throughout childhood were not associated with IA. In addition, mean antigen-specific IgG4 concentrations in infancy (age <2 years) were not associated with risk of IA nor progression to T1D. Higher ovalbumin IgG4 at first IA positive visit was marginally associated with progression to T1D (Hazard Ratio: 1.39, 95% Confidence Interval: 1.00, 1.92). Conclusion We found no association between the IgG4 response to β-lactoglobulin, gluten, and the development of either IA or T1D. The association between higher ovalbumin and progression to T1D in children with IA should be explored in other populations.
Del Prometeo griego al de la era-biós de la tecnociencia. Reflexiones bioéticas

espanolLas grandes civilizaciones nos han legado aprendizajes culturales valiosos para entendernos y entender el mundo actual de la Sociedad global. Dichos aprendizajes expresan sus verdades en narraciones mitologicas con lenguajes claro-oscuros de misteriosa riqueza simbolica. Son verdades sapienciales, no cientificas. Asi lo hacen los libros sagrados de las religiones historicas y las etnias para educar a los suyos en los principios y valores que aportan identidad cultural y recursos de supervivencia. El mito de Prometeo es un buen ejemplo de aquellas verdades sapienciales que el lenguaje humano no logra expresar sin recurrir a los simbolos, la metafora, al misterio. EnglishGreat civilizations have bequeathed us valuable cultural learning to understand us and understand the current world of global society. These learnings express their truths in mythological narratives with clear-dark languages of mysterious symbolic richness. They are sapiential, non-scientific truths. So do the sacred books of historical religions and ethnicities to educate their own in the principles and values that bring cultural identity and survival resources. The myth of Prometheus is a good example of those wisdom truths that human language cannot express without resorting to symbols, metaphor, mystery.
On the role of dopamine in motivated behavior

Neuro-computational models allow to study the brain mechanisms involved in intelligent behavior and extract essential computational principles which can be implemented in cognitive systems. They are a promising solution to achieve a brain-like artificial intelligence that can compete with natural intelligence on realistic behaviors. A crucial property of intelligent behavior is motivation, defined as the incentive to interact with the world in order to achieve specific goals, either extrinsic (obtaining rewards such as food or money, or avoiding pain) or intrinsic (satisfying one’s curiosity, fun). In the human brain, motivated or goal-directed behavior depends on a network of different structures, including the prefrontal cortex, the basal ganglia and the limbic system. Dopamine, a neurotransmitter associated with reward processing, plays a central role in coordinating the activity of this network. It structures processing in high-level cognitive areas along a limbic-associative-motor gradient and impacts the learning capabilities of the whole system. In this habilitation thesis, I present biologically-constrained neuro-computational models which investigate the role of dopamine in visual object categorization and memory retrieval (Vitay and Hamker, 2008), reinforcement learning and action selection (Vitay and Hamker, 2010), the updating, learning and maintenance of working memory (Schroll et al., 2012) and timing processes (Vitay and Hamker, 2014). These models outline the many mechanisms by which the dopaminergic system regulates cognitive and emotional behavior: bistable processing modes in the cerebral cortex, modulation of synaptic transmission and plasticity, allocation of cognitive resources and signaling of relevant events. Finally, I present a neural simulator able to simulate a variety of neuro-computational models efficiently on parallel architectures (Vitay et al., 2015).
Data-driven weak universal redundancy

In applications involving estimation, the relevant model classes of probability distributions are often too complex to admit estimators that converge to the truth with convergence rates that can be uniformly bounded over the entire model class as the sample size increases (uniform consistency). While it is often possible to get pointwise guarantees, so that the convergence rate of the estimator can be bounded in a model-dependent way, such pointwise gaurantees are unsatisfactory - estimator performance is a function of the very unknown quantity that is being estimated. Therefore, even if an estimator is consistent, how well it is doing may not be clear no matter what the sample size. Departing from this traditional uniform/pointwise dichotomy, a new analysis framework is explored by characterizing model classes of probability distributions that may only admit pointwise guarantees, yet where all the information about the unknown model needed to gauge estimator accuracy can be inferred from the sample at hand. To provide a focus to this suggested broad new paradigm, we analyze the universal compression problem in this data-driven pointwise consistency framework.
Niclosamide suppresses Hepatoma cell proliferation via the Wnt pathway

Background The Wnt pathway plays an important role in Hepatocarcinogenesis. We analyzed the association of the Wnt pathway with the proliferation of hepatoma cells using Wnt3a and niclosamide, a drug used to treat tapeworm infection. Methods We performed an MTS assay to determine whether Wnt3a stimulated proliferation of Huh-6 and Hep3B human hepatoma cell lines after 72 hours of incubation with Wnt3a in serum-free medium. The cells were subjected to hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) after 48 hours of incubation. RNA was isolated 48 hours after addition of Wnt3a or niclosamide, and cyclin D1 expression levels were analyzed by real-time quantitative polymerase chain reaction. The promoter activity of T-cell factor was analyzed by luciferase assay 48 hours after transfection of TOPflash. Western blot analysis was performed with antibodies against β-catenin, dishevelled 2, and cyclin D1. Results Cell proliferation increased with Wnt3a. Niclosamide suppressed proliferation with or without Wnt3a. Hematoxylin and eosin and TUNEL staining suggested that apoptosis occurred in cells with niclosamide. Cyclin D1 was upregulated in the presence of Wnt3a and downregulated with addition of niclosamide. The promoter activity of T-cell factor increased with Wnt3a, whereas T-cell factor promoter activity decreased with niclosamide. Western blot analysis showed that Wnt3a upregulated β-catenin, dishevelled 2, and cyclin D1, while niclosamide downregulated them. Conclusion Niclosamide is a potential candidate for the treatment of hepatoma.