Miracle-dz/UniFAR-FTUs huggingface dataset:
Encoding of High Frequencies Improves with Maturation of Action Potential Generation in Cultured Neocortical Neurons

The ability of neocortical neurons to detect and encode rapid changes at their inputs is crucial for basic neuronal computations, such as coincidence detection, precise synchronization of activity and spike-timing dependent plasticity. Indeed, populations of cortical neurons can respond to subtle changes of the input very fast, on a millisecond time scale. Theoretical studies and model simulations linked the encoding abilities of neuronal populations to the fast onset dynamics of action potentials (APs). Experimental results support this idea, however mechanisms of fast onset of APs in cortical neurons remain elusive. Studies in neuronal cultures, that are allowing for accurate control over conditions of growth and microenvironment during the development of neurons and provide better access to the spike initiation zone, may help to shed light on mechanisms of AP generation and encoding. Here we characterize properties of AP encoding in neocortical neurons grown for 11–25 days in culture. We show that encoding of high frequencies improves upon culture maturation, which is accompanied by the development of passive electrophysiological properties and AP generation. The onset of APs becomes faster with culture maturation. Statistical analysis using correlations and linear model approaches identified the onset dynamics of APs as a major predictor of age-dependent changes of encoding. Encoding of high frequencies strongly correlated also with the input resistance of neurons. Finally, we show that maturation of encoding properties of neurons in cultures is similar to the maturation of encoding in neurons studied in slices. These results show that maturation of AP generators and encoding is, to a large extent, determined genetically and takes place even without normal micro-environment and activity of the whole brain in vivo. This establishes neuronal cultures as a valid experimental model for studying mechanisms of AP generation and encoding, and their maturation.
Dynamical criticality during induction of anesthesia in human ECoG recordings

In this work we analyze electro-corticography (ECoG) recordings in human subjects during induction of anesthesia with propofol. We hypothesize that the decrease in responsiveness that defines the anesthetized state is concomitant with the stabilization of neuronal dynamics. To test this hypothesis, we performed a moving vector autoregressive analysis and quantified stability of neuronal dynamics using eigenmode decomposition of the autoregressive matrices, independently fitted to short sliding temporal windows. Consistent with the hypothesis we show that while the subject is awake, many modes of neuronal activity oscillations are found at the edge of instability. As the subject becomes anesthetized, we observe statistically significant increase in the stability of neuronal dynamics, most prominently observed for high frequency oscillations. Stabilization was not observed in phase randomized surrogates constructed to preserve the spectral signatures of each channel of neuronal activity. Thus, stability analysis offers a novel way of quantifying changes in neuronal activity that characterize loss of consciousness induced by general anesthetics.
Identification of Causal Parameters in Randomized Studies With Mediating Variables

Treatments in randomized studies are often targeted to key mediating variables. Researchers want to know if the treatment is effective and how the mediators affect the outcome. The data are often analyzed using structural equation models (SEMs), and model coefficients are interpreted as effects. However, only assignment to treatment groups is randomized, so mediators are self-selected treatments. Thus, the so-called direct effects of mediators on later outcomes do not usually warrant a causal interpretation. Holland (1988) studied the case of a single continuous mediator, criticizing the use of SEMs. He uses treatment assignment as an instrument for the effect of the mediator on the outcome. However, the assumptions he made to justify this approach are overly strong and substantively implausible. This article (a) makes explicit the assumptions needed to justify equating the parameters of SEMs with the effects of mediators, (b) provides weaker and more plausible conditions under which the instrumental variable estimand may be interpreted as an effect, and (c) extends the analysis to include the case of noncompliance.
Procedural skill learning in obstructive sleep apnea syndrome.

STUDY OBJECTIVES To better characterize the cognitive deficits observed in obstructive sleep apnea syndrome (OSAS) by examining procedural skill learning abilities. DESIGN Procedural skill learning was assessed using Mirror Tracing and Rotary Pursuit skill learning tasks. Subjects also completed a comprehensive neuropsychological test battery. SETTING Cognitive testing was performed during the day following the second of two consecutive nights during which sleep and respiratory variables were recorded. PARTICIPANTS Two groups (28 OSAS patients and 18 normal controls) with equivalent mean age and education levels. INTERVENTIONS N/A. MEASUREMENTS AND RESULTS No significant differences in learning rates were observed between the groups on the Rotary Pursuit Task. On the Mirror Tracing Task, overall learning of the skill and transfer to a new figure or to the reverse tracing direction was similar in the OSAS and NC groups. However, there was a subgroup of OSAS subjects (n=11) who showed marked difficulties in the initial acquisition of the Mirror Tracing Task. This subgroup's performance was no longer significantly different from that of controls and OSAS subjects without initial adaptation difficulty in the subsequent trials. Performance of subjects who had difficulty with initial adaptation on the Mirror Tracing was also significantly lower on tests of frontal executive function, but not on episodic memory tests. Sleep and respiratory variables did not distinguish between the two subgroups of OSAS patients. However, none of the young OSAS subjects (<40 years) presented this deficit. CONCLUSION Results indicate that contrary to this study's hypothesis, OSAS patients did not show procedural skill learning deficits. A subgroup of OSAS patients, however, did show deficits in initial skill adaptation and difficulties on other neuropsychological tests. Frontal dysfunction and decrement in psychomotor efficiency and vigilance appeared to be the most consistent explanation for characterizing the profile of neuropsychological test results among the OSAS patients.
The Temptation of Emergence or: Don't Rush into Economic(al) Explanations

One of the pioneering stock market simulations, the Santa Fe Institute Artificial Stock Market (SFI-ASM), showed an influence of learning speed on the aggregate outcome. For slow learning rates, the neoclassical properties of a homogeneous rational expectations equilibrium (hree) could be confirmed. However, a complex regime with higher price volatility, GARCH-behavior, cross-correlation between price and trading volume, and significant levels of technical trading emerged for faster learning speeds. In Ehrentreich (200x) it was shown that these results are based on the specific design of the mutation operator which introduced an upward bias in the level of set trading bits in the classifier system. Since agents in a corrected version endogenously gave up the use of their classifier system, it was implied that it did not provide any profitable trading information. This is in contrast to the original SFI-ASM. Joshi, Parker, and Bedau (1998) found that agents with access to technical trading bits did significantly better with respect to wealth levels than those without. In their 2002 study they found that faster learning agents outperformed slow learning agents. A sensitivity analysis of wealth levels with both the original and the corrected mutation operator was able to replicate the Joshi, Parker, and Bedau results, however only for specific parameter settings. It was revealed that differences in wealth levels are a result of the size of the active rule set that an agent possesses. It was a peculiarity of design in the SFI-ASM that trading rules were not always logical. The more trading bits were set, the higher the fraction of illogical trading rules. For faster learning rates, the number of logical and thus potentially activated trading rules decreased significantly. This had an effect on the efficiency of the selection mechanisms (Select Best and Roulette Wheel) that were used to determine the rules on which agents acted upon. Contour plots show that the differences in wealth levels between two agent types, who differ in the size of the rule set and learning speeds, can be positive or negative, depending on the specific parameter combination. Any economic interpretation of differences in wealth levels are thus too hasty, since these differences are again a result of technicalities in the model, unless one is willing to interpret cognitive or economic substance into the working of the selection mechanisms. Unexpected results that are hard to explain on the basis of the constituting elements in a simulation model pose a general temptation to explain them as emergent behavior, yet they can still be a result of unsuspicious programming details. Since the two selection mechanisms are widely used in the agent-based community, the necessity of having a constant number of active strategies over the course of the simulation is demonstrated. Because of this, the above analysis could be of general interest to the agent-based simulation community.
Hypomyelinating leukodystrophies: Translational research progress and prospects

Hypomyelinating leukodystrophies represent a genetically heterogeneous but clinically overlapping group of heritable disorders. Current management approaches in the care of the patient with a hypomyelinating leukodystrophy include use of serial magnetic resonance imaging (MRI) to establish and monitor hypomyelination, molecular diagnostics to determine a specific etiology, and equally importantly, careful attention to neurologic complications over time. Emerging research in oligodendrocyte biology and neuroradiology with bedside applications may result in the possibility of clinical trials in the near term, yet there are significant gaps in knowledge in disease classification, characterization, and outcome measures in this group of disorders. Here we review the biological background of myelination, the clinical and genetic variability in hypomyelinating leukodystrophies, and the insights that can be obtained from current MRI techniques. In addition, we discuss ongoing research approaches to define potential outcome markers for future clinical trials. Ann Neurol 2014;76:5–19
Practical Tools for Monitoring Convergence, Integration and Development: Compare and Apply

Abstract It is generally believed that an adequate set of indices can serve as a useful tool for monitoring processes or developments like integration, measuring and comparing performance for policy analysis and evaluation. To this aim, many institutions and especially statistical offices all over the world prepare several hundreds of such indicators to monitor their development targets. Unfortunately, many of them are quite deficient in several aspects. This article introduces indices as practical tools to monitor integration, globalization, and development, and puts its main focus on multidimensionality, feasibility, universality and comparability. This indicator system is easily implemented and applicable worldwide; it applies equally well to North–North, North–South, or South–South agreements. The indices are illustrated by monitoring and comparing the WAEMU (representing South–South areas), the NAFTA (North–South area), the ANZCERTA and the EU-15 (North–North areas). Due to the issue of measurability and as they often are of major interest, special focus is put on economic aspects.
Causal Relation between Money Supply and Exchange Rate in India Under the Basket Peg and Market Determination Regimes: A Time Series Analysis

: Mundell-Fleming model of open economy macroeconomics has amply established that the nature and direction of causal relationship between money supply and exchange rate depend on the exchange rate regimes. Particularly bidirectional causal relation between domestic money supply and exchange rate is the common phenomenon in the pegged regime of exchange rate, while unidirectional causality running from money supply to exchange rate is the feature of the market determination regime. This study is devoted to enquire into these issues in the context of Indian exchange rate regimes. Using quarterly time series data of the variables concerned, the study bears the evidence that under the basket peg and market determination exchange rate regimes money supply and rupee/dollar exchange rate in India are cointegrated. In the era of basket peg, bidirectional Granger causality is established, while in the era of market determined regime, unidirectional Granger causality running from money supply to exchange rate has been testified.
What is Local and for What Foods Does it Matter

Consumer demand for local foods has been increasing dramatically over the past several years. Many food producers and marketers are raising their capacity to incorporate local food. Revenue from local Farmers’ Market and Community Supported Agriculture has become a greater source of income particularly for small and medium-sized farms. This study answers two important questions related to local food that have not been sufficiently addressed before: what is the greatest distance food can travel and still be accepted by consumers as local and is "local" equally important across food categories. Using survey data from two states in the USA, this research found that consumers’ accepted food travel distance may be much shorter than what is generally believed. In addition, there exists a great variation in the importance rating consumers attach to “being local” for different food categories and these differences are related to consumer characteristics.
Dual gene transfer of bFGF and PDGF in a single plasmid for the treatment of myocardial infarction

Basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) have been shown to be involved in a spectrum of cellular processes. In a previous study, we constructed a novel multigenic vector that contained two separate transcription units, each consisting of a strong promoter and an efficient polyadenylation signal. The two promoters were chosen for their ability to work simultaneously. Dual gene transfer of bFGF and PDGF in a single plasmid resulted in a significant increase in collateral blood vessel formation in a rabbit model of hind limb ischemia. The aim of the present study was to investigate the effect of this dual gene transfer strategy in a rat model of acute myocardial infarction (AMI). AMI was induced in rats by ligation of the left anterior descending coronary artery. The animals were randomly divided into four groups and treated with the following therapeutic strategies: Empty plasmid (control), plasmid encoding bFGF (PL-bFGF), plasmid encoding PDGF (PL-PDGF) or plasmid encoding bFGF and PDGF (PL-F-P). Echocardiography and histological examinations were performed 28 days subsequent to gene transfer. Dual gene therapy with bFGF and PDGF resulted in a significant angiogenic effect accompanied by vessel maturation, along with a significant reduction in infarct size and improvement in cardiac function. In a rat model of AMI, single plasmid-mediated dual gene therapy with bFGF and PDGF decreased infarct size and improved cardiac function due to the formation of functionally and morphologically mature vasculature. These results are relevant to the ongoing clinical trials involving the use of single plasmid-mediated angiogenic factors for the treatment of myocardial ischemic disease.
FX Options and Structured Products

Preface. Scope of this Book. The Readership. About the Author. Acknowledgments. 1 Foreign Exchange Options. 1.1 A Journey through the History Of Options. 1.2 Technical Issues for Vanilla Options. 1.3 Volatility. 1.4 Basic Strategies containing Vanilla Options. 1.5 First Generation Exotics. 1.6 Second Generation Exotics. 2 Structured Products. 2.1 Forward Products. 2.2 Series of Strategies. 2.3 Deposits and Loans. 2.4 Interest Rate and Cross Currency Swaps. 2.5 Participation Notes. 3 Practical Matters. 3.1 The Traders' Rule of Thumb. 3.2 Bid-Ask Spreads. 3.3 Settlement. 3.4 On the Cost of Delayed Fixing Announcements. 4 Hedge Accounting under IAS 39. 4.1 Introduction. 4.2 Financial Instruments. 4.3 Evaluation of Financial Instruments. 4.4 Hedge Accounting. 4.5 Methods for Testing Hedge Effectiveness. 4.6 Testing for Effectiveness - A Case Study of the Forward Plus. 4.7 Conclusion. 4.8 Relevant Original Sources for Accounting Standards. 4.9 Exercises. 5 Foreign Exchange Markets. 5.1 A Tour through the Market. 5.2 Software and System Requirements. 5.3 Trading and Sales. Bibliography. Index.
Clinical and laboratory analysis of late-onset glutaric aciduria type I (GA-I) in Uighur: A report of two cases

The aim of the present study was to investigate the clinical, biochemical and genetic mutation characteristics of two cases of late-onset glutaric aciduria type I (GA-I) in Uighur. The clinical data and glutaryl-CoA dehydrogenase (GCDH) genetic test results of two cases of late-onset GA-I in Uighur were collected and analyzed, and reviewed with relevant literature. One patient with late-onset GA-I primarily exhibited clinical intermittent headache, while the other patient was asymptomatic. The urinary organic acid analysis detected a large number of glutaric acid and 3-hydroxy glutaric acid, 3-hydroxy-propionic acid. One patient exhibited white matter degeneration in cranial magnetic resonance imaging (MRI) and the other patient showed no abnormality. The two patients both exhibited c. 1204C >T, p.R402W, heterozygous mutation, and c. 532G >A, p.G178R, heterozygous mutation. Besides central nervous system infectious diseases, patients with clinical headache, cranial MRI-suggested bilateral temporal lobe arachnoid cyst and abnormal signals in the basal ganglia should be highly suspected as late-onset GA-I. Early diagnosis and correct treatment are key to improve its prognosis.
Generalized Game Trees

We consider two generalizations of the standard two-player game model: different evaluation functions for the players, and more than two players. Relaxing the assumption that players share the same evaluation function produces a hierarchy of levels of knowledge as deep as the search tree. Alpha-beta pruning is only possible when the different evaluation functions behave identically. In extending the standard model to more than two players, the minimax algorithm is generalized to the maxn algorithm applied to vectors of N-tuples representing the evaluations for each of the players. If we assume an upper bound on the sum of the components for each player, and a lower bound on each individual component, then shallow alpha-beta pruning is possible, but not deep pruning. In the best case, the asymptotic branching factor is reduced to (1 + √46-3)/2. In the average case, however, pruning does not reduce the asymptotic branching factor. Thus, alpha-beta pruning is found to be effective only in the special case of two players with a common evaluation function.
Eager writeback-a technique for improving bandwidth utilization

Modern high-performance processors utilize multi-level cache structures to help tolerate the increasing latency of main memory. Most of these caches employ either a writeback or a write-through strategy to deal with store operations. Write-through caches propagate data to more distant memory levels at the time each store occurs, which requires a very large bandwidth between the memory hierarchy levels. Writeback caches can significantly reduce the bandwidth requirements between caches and memory by marking cache lines as dirty when stores are processed and writing those lines to the memory system only when that dirty line is evicted. Unfortunately, for applications that experience significant numbers of cache misses due to streaming data, writeback cache designs can degrade overall system performance by clustering bus activity when dirty lines contend with data being fetched into the cache. In this paper we present a new technique called Eager Writeback, which re-distributes and balances memory traffic by writing and "cleaning" dirty cache lines prior to their eviction. Eager Writeback can be viewed as a compromise between write-through and writeback policies, in which dirty lines are written later than write-through, but prior to writeback. We will show that this approach can reduce the large number of writes seen in a write-through design, while avoiding the performance degradation caused by clustering bus traffic in a writeback approach.
CP 04 Tutorial : Distributed Constraints Satisfaction Algorithms , Performance , Communication ?

Distributed constraints satisfaction problems (DisCSPs) have been studied for over a decade. The first distributed search algorithm was asynchronous backtracking, which is still the most studied. In the last few years, several new families of distributed search algorithms have been investigated and comparative experimental studies are encouraging. A natural extension to distributed constraints satisfaction is distributed constraints optimization. Stochastic search algorithms for solving DisCSPs, such as Distributed Breakout, have appeared a few years ago. Distributed stochastic search algorithms are naturally suitable for solving distributed optimization. In contrast, asynchronous search algorithms for distributed optimization have been proposed in recent years. Due to the distributed nature of the problem, message delay can have unexpected effects on the behavior of algorithms on DisCSPs. This has been shown in an experimental study that induced random delays on messages sent among agents. In order to study the impact of message delays on DisCSP search, a model of delays in terms of concurrent performance measures is needed. Within such a model, the behavior of families of search algorithms in the presence of delays is varied and interesting. An important feature of the distribution of the problem among agents is their ability to maintain some privacy. Agents may not want to share their values with other agents, and they may wish to keep constraints as private as possible. Some recent work has resulted in versions of asynchronous backtracking that maintain both privacy of values and privacy of constraints. Other investigations of privacy in DisCSPs focused on the analysis of information gain by studying a welldefined problem, that of scheduling meetings of agents.
A common mechanism for adaptive scaling of reward and novelty

Declarative memory is remarkably adaptive in the way it maintains sensitivity to relative novelty in both unknown and highly familiar environments. However, the neural mechanisms underlying this contextual adaptation are poorly understood. On the basis of emerging links between novelty processing and reinforcement learning mechanisms, we hypothesized that responses to novelty will be adaptively scaled according to expected contextual probabilities of new and familiar events, in the same way that responses to prediction errors for rewards are scaled according to their expected range. Using functional magnetic resonance imaging in humans, we show that the influence of novelty and reward on memory formation in an incidental memory task is adaptively scaled and furthermore that the BOLD signal in orbital prefrontal and medial temporal cortices exhibits concomitant scaled adaptive coding. These findings demonstrate a new mechanism for adjusting gain and sensitivity in declarative memory in accordance with contextual probabilities and expectancies of future events. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.