Miracle-dz/UniFAR-FTUs huggingface dataset:
Resources in Economic Geography: From Substantive Concepts towards a Relational Perspective

Resources are crucial for the technological and economic development of firms in spatial perspective. In this paper we contrast two ways of conceptualizing resources, and argue that a conventional, substantive understanding implies a number of shortcomings which can be overcome through the application of a relational conception of resources. In examining four types of resources—material resources, knowledge, power, and social capital—our argument is that resources are constituted in a relational way in two aspects. First, resources are relational in that their generation, interpretation, and use are contingent. This depends on the particular institutional structures and social relations, as well as on the knowledge contexts and mental models of the agents involved. Second, some types of resources, such as power and social capital, are also relational because they cannot be possessed or controlled by individual agents. They are built and mobilized through day-to-day social practices. Individuals or groups of agents may appropriate the returns, but not the resources themselves. We conclude that a relational concept reflects the contextual and interactive nature of the selection, use, and formation of resources. This offers new insights into the explanation of heterogeneity in firm strategies and trajectories, as well as regional differences in the development of localized industry configurations, such as clusters.
Transport Level Optimisations for Streaming Media Over Wide-area Wireless Neworks

Wide-area cellular data networks (e.g. GPRS, CDMA 2000) are gaining popularity to provide “always-on” data connectivity to mobile users. However, the characteristics of the wide-area wireless links present several new challenges to different applications. In this paper we focus on optimization techniques to improve the application performance of streaming media systems operating over wide-area wireless networks. Through detailed measurements in commercial wide-area cellular networks we generated traces to evaluate the performance of our proposed mechanisms. We make three contributions in the context of media streaming over wide-area wireless links: (1) perform a detailed analysis of the channel characteristics, (2) identify general optimisation techniques to reduce jitter for streaming applications, and (3) define a scheme to provide Unequal Error Protection (UEP) for multimedia streams. Due to deployability constraints inside the cellular service provider’s network, our scheme defines an application-level inferencing technique that adapts itself to the characteristics of the underlying wireless link.
Determinants of plasma 25-hydroxyvitamin D and development of prediction models in three US cohorts – CORRIGENDUM

Epidemiological and other evidence suggests that vitamin D may be protective against several chronic diseases. Assessing vitamin D status in epidemiological studies, however, is challenging given finite resources and limitations of commonly used approaches. Using multivariable linear regression, we derived predicted 25-hydroxyvitamin D (25(OH)D) scores based on known determinants of circulating 25(OH)D, including age, race, UV-B radiation flux at residence, dietary and supplementary vitamin D intakes, BMI, physical activity, alcohol intake, post-menopausal hormone use (women only) and season of blood draw, in three nationwide cohorts: the Nurses' Health Study, Nurses' Health Study II and the Health Professionals Follow-up Study. The model r 2 for each cohort ranged from 0·25 to 0·33. We validated the prediction models in independent samples of participants from these studies. Mean measured 25(OH)D levels rose with increasing decile of predicted 25(OH)D score, such that the differences in mean measured 25(OH)D between the extreme deciles of predicted 25(OH)D were in the range 8·7-12·3 ng/ml. Substituting predicted 25(OH)D scores for measured 25(OH)D in a previously published case-control analysis of colorectal cancer yielded similar effect estimates with OR of approximately 0·8 for a 10 ng/ml difference in either plasma or predicted 25(OH)D. We conclude that these data provide reasonable evidence that a predicted 25(OH)D score is an acceptable marker for ranking individuals by long-term vitamin D status and may be particularly useful in research settings where biomarkers are not available for the majority of a study population.
Determinants of Tax Evasion Behavior: Empirical Evidence from Survey Data

Tax revenues are major and important income sources for governments in most countries. Sufficient tax revenues make many government projects possible and help elected officials and politicians to remain in office longer if the government implements programs and projects demanded by the public. In today’s globalizing economic environments, there is increasing demand for a variety of public services and programs. However, the rate of increase in the tax revenues to finance these public services and programs falls short of the necessary public spending. The potential tax revenue of a country based on its legal or tax law is much larger than the tax revenues that are actually collected. Due to the lack of full tax compliance, government budgets are rarely balanced in most countries, and the gap between revenue and spending is increasing. The main question is why taxpayers evade taxes. To understand tax evasion, one can examine what factors cause taxpayers to evade taxes. If factors that affect tax evasion are identified, policies can be developed to prevent tax evasion.The purpose of this study is to investigate factors related to tax evasion behavior using survey data collected in Turkey. Factor analysis and multiple regression techniques are employed. The results show that taxational and fiscal factors, economic factors, demographic factors, administrative factors, and other factors have statistically significant effects on tax evasion behavior.
Exploring place through user-generated content: Using Flickr tags to describe city cores

Terms used to describe city centers, such as Downtown, are key concepts in everyday or vernacular language. Here, we explore such language by harvesting georeferenced and tagged metadata associated with 8 million Flickr images and thus consider how large numbers of people name city core areas. The nature of errors and imprecision in tagging and georeferencing are quantified, and automatically generated precision measures appear to mirror errors in the positioning of images. Users seek to ascribe appropriate semantics to images, though bulk-uploading and bulk-tagging may introduce bias. Between 0.5–2% of tags associated with georeferenced images analyzed describe city core areas generically, while 70% of all georeferenced images analyzed include specific place name tags, with place names at the granularity of city names being by far the most common. Using Flickr metadata, it is possible not only to describe the use of the term Downtown across the USA, but also to explore the borders of city center neighborhoods at the level of individual cities, whilst accounting for bias by the use of tag profiles.
Global shipping IPOs performance

We analyze the short- and long-run price performance of 143 global shipping IPOs listed during the 1984–2007 period in major stock exchanges, computing Buy-and-Hold Abnormal Returns (BHARs) and Cumulative Average Returns (CARs). We find the average underpricing for shipping IPOs to be 17.69%. The light underpricing is positively related to the age of the firm, the reputation of the stock exchange the IPO is listed in and the market condition of the period in which the firm went public, and negatively related to the reputation of the underwriters. In the long run, shipping IPOs underperform after a five-month holding period. Specifically, using the BHARs as a benchmark for long-run performance, we reveal that investors who buy immediately after listing and hold shares for 3 years will make a loss of 15.72%. The conclusions suggested by this survey of the global shipping industry surprises us regarding the maturity in the behavior of its investors.
Learning statistics based on the compendium and reproducible computing

This paper explains how the R Frame- work (wessa.net) and a newly developed Com- pendium Platform (freestatistics.org) allow us to cre- ate, use, and maintain documents that contain em- pirical research results which can be recomputed and reused in derived work. It is illustrated that this tech- nological innovation can be used to create educational applications that can be shown to support eective learning of statistics and associated analytical skills. It is explained how a Compendium can be created by anyone, without the need to understand the technical- ities of scientific word processing (L ATEX) or statistical computing (R code). The proposed system allows ed- ucational researchers to objectively measure key as- pects of the actual learning process based on individ- ual and constructivist activities such as: peer review, collaboration in research, computational experimen- tation, etc. The system was implemented and tested in three statistics courses in which the use of Com- pendia was used to create an interactive e-learning environment that simulated the real-world process of empirical scientific research.
Taxation and Family Labor Supply

I examine the impact of taxation on family labor supply and test economic models of the family by analyzing responses to the Tax Reform of 1991 in Sweden, known as the "tax reform of the century" because of its large magnitude. Using detailed administrative panel data on approximately 11% of the married Swedish population, I . nd that husbands and wives react substantially to their own marginal tax rates and to their spouses’rates. The estimates imply that husbands’leisure and wives’leisure are complements in the full sample. I test and reject a set of models in which the family maximizes a single utility function. The standard econometric labor supply specification, in which one spouse reacts to the other spouse’ income as if it were s unearned income, yields biased coe¢ cient estimates. Uncompensated labor supply elasticities are over-estimated by a factor of more than three, and income e¤ects are of the wrong sign. Overall, the results suggest that there is interplay between spouses’ labor supply decisions, and that taking account of this joint aspect of their decision- making leads to new conclusions about labor supply responses to taxation.
The Expectations Hypothesis of the Term Structure : A Look at the Polish Interbank Market

This paper tests the expectations hypothesis (EH) for the short end of the Polish interbank term structure. Employing daily data, the hypothesis that the actual yield spread is an unbiased predictor of the perfect foresight spread is tested. Additionally, Johansen's FIML procedure is used in order to explore the dynamic comovement of yields across the term structure and also test the parameter restrictions imposed by the EH. The empirical findings provide some evidence in favor of the EH. In particular, there is evidence that all yields share a common stochastic trend. Furthermore, at the margin, the EH restrictions imposed on the cointegration space are not rejected. On balance, one might conclude that the EH is not grossly at variance with the data.
Quantum optics with quantum dots in photonic wires: Basics and application to “ultrabright” single photon sources

We review recent experimental and theoretical results, which highlight the strong interest of the photonic wire (PW) geometry for quantum optics experiments with solid-state emitters, and for quantum optoelectronic devices. By studying single InAs QDs embedded within single-mode cylindrical GaAs PW, we have noticeably observed a very strong (16 fold) inhibition of their spontaneous emission rate in the thin-wire limit, and a nearly perfect funnelling of their spontaneous emission into the guided mode for larger PWs. We present a novel single-photon-source based on the emission of a quantum dot embedded in an engineered PW, comprising a tapered tip so as to control the radiation pattern, and an integrated hybrid bottom mirror. Unlike microcavity-based devices, this source displays for the first time simultaneously a record-high efficiency (0.73 photon per pulse) and a very low g(2) parameter. Numerical simulations show that an efficiency higher than 0.9 can be obtained for optimized structures, under either optical or electrical pumping.
What Do We Know About Microfinance at Macro Glance?

The majority of microfinance impact studies focus on finding their effect on a specific group of beneficiaries, in contrast we aim to identify the impact on whole economies (economic growth, and financial sector development and reductions in income inequalities), which is an important policy concern, not previously addressed. To address heterogeneity across countries, we group countries into three broad clusters delineated by a set of macro-institutional determinants. We find long-term evidence of a significant ability of microfinance to affect broader economies. Moreover, the impact and dynamics differ substantially by macro-institutional environment; the microfinance effect is more pronounced in weaker environments.
A multicenter experience with generic mycophenolate mofetil conversion in stable liver transplant recipients

Purpose Generic substitution of brand-name medications can lead to significant cost savings and is an accepted medical practice. This study evaluated clinical and safety outcomes among liver transplant recipients whose mycophenolate mofetil (MMF) was converted from the brand-name formulation (Cellcept) to a generic formulation (My-rept). Methods Clinical data from multiple centers were prospectively collected for determination of complications, safety, and quality of life after in 154 clinically stable, adult liver transplant recipients whose MMF was converted to a generic formulation between April 2010 and September 2012. This protocol was approved by Institutional Review Boards of all involved sites. Results In eight patients (5.19%), nine instances of drug-related complications occurred after medication conversion. Half of these complications were gastrointestinal disorders (n = 4), and most (7 of 9) were mild. No significant differences were noted in mean pre- and postconversion gastrointestinal symptoms via a rating system (8.9 vs. 10.4) or gastrointestinal quality-of-life index scores (125.6 vs. 123.1). More than 90% of patients reported a status of "about the same" when questioned about the brand-name and generic formulation using the Patient Overall Treatment Effect and Investigator Overall Treatment Effect measures. The incidence of serious adverse events was 5.8%. Acute rejection occurred in two patients, with no graft loss or death. Conclusion Clinical experience as well as research data showed that generic MMF was comparable in efficacy to the brand-name drug. Given the lack of adverse events and the safety findings, conversion from brand-name MMF to generic MMF should be encouraged.
Multiple View Oriented Matching Algorithm for People Reidentification

People reidentification is one of the most challenging tasks in computer vision, and considerable efforts have been directed toward providing solutions to this problem. The existence of extensive camera networks and surveillance systems increases the amount of people images obtained, but, on the other hand, implies the need for new algorithms to enable reidentification of people captured by the cameras. There is no one optimal model that solves the entire problem, but a set of distinctive features can be used to help in the matching process. Our proposal consists of using the orientation of each person captured in the surveillance scene to considerably improve the reidentification process. An iterative algorithm maximizes the number of successful matches and speeds up the process. A comparison with other earlier relevant studies is presented using available datasets.
A Retinal Source of Spatial Contrast Gain Control

Sensory cortex is able to encode a broad range of stimulus features despite a great variation in signal strength. In cat primary visual cortex (V1), for example, neurons are able to extract stimulus features like orientation or spatial configuration over a wide range of stimulus contrasts. The contrast-invariant spatial tuning found in V1 neuron responses has been modeled as a gain control mechanism, but at which stage of the visual pathway it emerges has remained unclear. Here we describe our findings that contrast-invariant spatial tuning occurs not only in the responses of lateral geniculate nucleus (LGN) relay cells but also in their afferent retinal input. Our evidence suggests that a similar contrast-invariant mechanism is found throughout the stages of the early visual pathway, and that the contrast-invariant spatial selectivity is evident in both retinal ganglion cell and LGN cell responses.
Coding Psychological Constructs in Text Using Mechanical Turk: A Reliable, Accurate, and Efficient Alternative

In this paper we evaluate how to effectively use the crowdsourcing service, Amazon's Mechanical Turk (MTurk), to content analyze textual data for use in psychological research. MTurk is a marketplace for discrete tasks completed by workers, typically for small amounts of money. MTurk has been used to aid psychological research in general, and content analysis in particular. In the current study, MTurk workers content analyzed personally-written textual data using coding categories previously developed and validated in psychological research. These codes were evaluated for reliability, accuracy, completion time, and cost. Results indicate that MTurk workers categorized textual data with comparable reliability and accuracy to both previously published studies and expert raters. Further, the coding tasks were performed quickly and cheaply. These data suggest that crowdsourced content analysis can help advance psychological research.
Scalable lazy SMT-based motion planning

We present a scalable robot motion planning algorithm for reach-avoid problems. We assume a discrete-time, linear model of the robot dynamics and a workspace described by a set of obstacles and a target region, where both the obstacles and the region are polyhedra. Our goal is to construct a trajectory, and the associated control strategy, that steers the robot from its initial point to the target while avoiding obstacles. Differently from previous approaches, based on the discretization of the continuous state space or uniform discretization of the workspace, our approach, inspired by the lazy satisfiability modulo theory paradigm, decomposes the planning problem into smaller subproblems, which can be efficiently solved using specialized solvers. At each iteration, we use a coarse, obstacle-based discretization of the workspace to obtain candidate high-level, discrete plans that solve a set of Boolean constraints, while completely abstracting the low-level continuous dynamics. The feasibility of the proposed plans is then checked via a convex program, under constraints on both the system dynamics and the control inputs, and new candidate plans are generated until a feasible one is found. To achieve scalability, we show how to generate succinct explanations for the infeasibility of a discrete plan by exploiting a relaxation of the convex program that allows detecting the earliest possible occurrence of an infeasible transition between workspace regions. Simulation results show that our algorithm favorably compares with state-of-the-art techniques and scales well for complex systems, including robot dynamics with up to 50 continuous states.
In Silico Evidence for Gluconeogenesis from Fatty Acids in Humans

The question whether fatty acids can be converted into glucose in humans has a long standing tradition in biochemistry, and the expected answer is “No”. Using recent advances in Systems Biology in the form of large-scale metabolic reconstructions, we reassessed this question by performing a global investigation of a genome-scale human metabolic network, which had been reconstructed on the basis of experimental results. By elementary flux pattern analysis, we found numerous pathways on which gluconeogenesis from fatty acids is feasible in humans. On these pathways, four moles of acetyl-CoA are converted into one mole of glucose and two moles of CO2. Analyzing the detected pathways in detail we found that their energetic requirements potentially limit their capacity. This study has many other biochemical implications: effect of starvation, sports physiology, practically carbohydrate-free diets of inuit, as well as survival of hibernating animals and embryos of egg-laying animals. Moreover, the energetic loss associated to the usage of gluconeogenesis from fatty acids can help explain the efficiency of carbohydrate reduced and ketogenic diets such as the Atkins diet.
Electrospray Ionization Mass Spectrometry: A Technique to Access the Information beyond the Molecular Weight of the Analyte

The Electrospray Ionization (ESI) is a soft ionization technique extensively used for production of gas phase ions (without fragmentation) of thermally labile large supramolecules. In the present review we have described the development of Electrospray Ionization mass spectrometry (ESI-MS) during the last 25 years in the study of various properties of different types of biological molecules. There have been extensive studies on the mechanism of formation of charged gaseous species by the ESI. Several groups have investigated the origin and implications of the multiple charge states of proteins observed in the ESI-mass spectra of the proteins. The charged analytes produced by ESI can be fragmented by activating them in the gas-phase, and thus tandem mass spectrometry has been developed, which provides very important insights on the structural properties of the molecule. The review will highlight recent developments and emerging directions in this fascinating area of research.
Gallotannin-Enriched Extract Isolated from Galla Rhois May Be a Functional Candidate with Laxative Effects for Treatment of Loperamide-Induced Constipation of SD Rats

Several natural products containing tannins are used as traditional medicines for treatment of constipation; however, their pharmacological mechanism is not well understood. The laxative effects of gallotannin-enriched extract isolated from Galla Rhois (GEGR) were investigated using a constipation model induced by loperamide (Lop) injection. After analysis for antioxidant activity of GEGR, alterations in the excretion parameters, histological structure, mucin secretion, and related protein levels were measured in the transverse colon of Sprague Dawley (SD) rats with Lop-induced constipation following treatment with 250, 500 and 1,000 mg/ml of GEGR. The number and weight of feces increased significantly by 48–79% and 128–159%, respectively, in the Lop+GEGR treated group relative to the Lop+vehicle treated group, while food intake and water consumption were maintained at a constant level. The thickness of mucosa, muscle and flat luminal surface, as well as the number of goblet cells and crypt of lieberkuhn were enhanced in the Lop+GEGR treated group. Moreover, mucin secretion increased significantly in a dose dependent manner in the Lop+GEGR treated group. Furthermore, the downstream signaling pathway of the muscarinic acetylcholine receptors (mAChR) M2 and M3 was recovered by GEGR treatment, although the expression level varied. The levels of Gα expression and inositol triphosphate (IP3) concentration were also recovered in the Lop+GEGR treated group relative to the Lop+vehicle treated group. The results of the present study provide strong evidence that tannins distributed in various medicinal plants are important candidates for improving chronic constipation induced by Lop treatment in animal models.