Miracle-dz/UniFAR-FTUs huggingface dataset:
Federal Reserve Bank of Minneapolis Research Department Staff Report 428 Superstores or Mom and Pops? Technology Adoption and Productivity Differences in Retail Trade

———————————————————————————————————— I document that crosscountry productivity differences in retail trade, which employs around 20% of workers, are accounted for in large part by compositional differences. In richer countries , most retailing is done in modern stores, with high measured output per worker, whereas in developing countries, retail trade is dominated by less-productive traditional stores. I hypothesize that developing countries rationally adopt few modern stores since car ownership rates are low. A simple quantitative model of home production supports the role of cars in determining the composition of retail technologies used and retail-sector productivity differences across countries. Summer Institute. For help with a wide variety of data sources, I thank Karin Murphy and Brooke Tosi; for help with Mexican data, I thank Marcelo Ore Vásquez and Javier Pérez Estrada; and for help with Cypriot data, I thank Alexis Antoniades and Sofronis Clerides. For editorial assistance I thank Kathy Rolfe and Joan Gieseke. The views expressed herein are those of the author and not necessarily those of the Federal Reserve Bank of Minneapolis or the Federal Reserve System.
The Association between Foveal Morphology and Macular Pigment Spatial Distribution: An Ethnicity Study

Purpose Macular pigment (MP) spatial distribution varies considerably among individuals. We investigated ethnic variations in MP spatial distribution in relation to foveal architecture. Methods We measured MP optical density (MPOD) using heterochromatic flicker photometry (MAP test, City, University of London) in 76 white, 80 South Asian and 70 black volunteers (18 to 39 years). MPOD spatial profiles were classified objectively as exponential, ring-like or central dip, based on deviations away from an exponential fit. Measurements including total retinal thickness (RT), inner retinal layer (IRL), inner and outer plexiform layer (IPL and OPL) thickness, foveal width and foveal pit slope were taken from Spectralis SD-OCT (Heidelberg, Germany) scans. Results Integrated MPOD up to 1.8° (MPODint) was higher in South Asian (0.84±0.26) and black (0.84±0.31) than whites (0.63±0.24, P<0.0005). Ethnicity explained around 10% of the variance while gender played no significant role. MPOD profile phenotypes were associated with ethnicity: 58% with ring profiles were South Asian and 43% with dip profiles were black (χ2(4,226) = 13.4, P = 0.009). MPODint was lower in exponential (0.66±0.21) compared to ring-like (0.96±0.26) and central dip (1.00±0.32, P<0.0005) groups. White subjects had thicker IRL at 0° (130±21μm) than South Asian (123±16μm) and blacks (116±14μm; F(2) = 12.4, P<0.0005), with comparable results for IPL (P<0.0005) and OPL (P = 0.03). There was no significant difference in IRL, IPL or OPL (from 0 to 3.8° retinal eccentricity) or foveal width between MP profile groups (P>0.05). Conclusion We report a significant difference in the amount and distribution of MP between ethnicities that is not explained by variations in foveal morphology.
Simplified processing for high spectral efficiency wireless communication employing multi-element arrays

We investigate robust wireless communication in high-scattering propagation environments using multi-element antenna arrays (MEAs) at both transmit and receive sites. A simplified, but highly spectrally efficient space-time communication processing method is presented. The user's bit stream is mapped to a vector of independently modulated equal bit-rate signal components that are simultaneously transmitted in the same band. A detection algorithm similar to multiuser detection is employed to detect the signal components in white Gaussian noise (WGN). For a large number of antennas, a more efficient architecture can offer no more than about 40% more capacity than the simple architecture presented. A testbed that is now being completed operates at 1.9 GHz with up to 16 quadrature amplitude modulation (QAM) transmitters and 16 receive antennas. Under ideal operation at 18 dB signal-to-noise ratio (SNR), using 12 transmit antennas and 16 receive antennas (even with uncoded communication), the theoretical spectral efficiency is 36 bit/s/Hz, whereas the Shannon capacity is 71.1 bit/s/Hz. The 36 bits per vector symbol, which corresponds to over 200 billion constellation points, assumes a 5% block error rate (BLER) for 100 vector symbol bursts.
Toward Management Innovation for IT-Enabled Operational Agility: a Dependencies Perspective

Firms make large investments in enterprise IT systems expecting positive impacts to their supply chain operations. Yet, though systems facilitate the responsibilities of multiple stakeholders, their success is not determined merely by its adoption. This study shows how management innovation is developed to affect operational agility of a firm. The model suggests that operational agility in supply chain requires constructing dependency structures and implementing coordinating mechanisms, to develop management innovation processes. In addition, the study prescribes a set of actionable guidelines to help managers classify and manage innovative firm management practices.
Time-Series and Cross-Sectional Excess Comovement in Stock Indexes

This paper is an empirical investigation of the excess comovement among 82 industry indexes in the U.S. stock market between January 5, 1976 and December 31, 2001. We define excess comovement as the covariation between two assets beyond what can be explained by fundamental factors. In our analysis, the fundamental factors are sector groupings and the three Fama-French factors. We then estimate residuals of joint (FGLS) rolling regressions of these fundamentals on industry returns. Finally, we compute excess comovement as the mean of square unconditional, statistically significant correlations of these residuals. We show that excess comovement is high (about 0.07, i.e., equivalent to an average absolute correlation of 0.26), statistically significant, and represents an economically significant portion (almost 30%) of the average gross square return correlation. Excess comovement is also uniformly significant across industries and over time and only weakly asymmetric, i.e., not significantly different in rising or falling markets. We explain more than 23% of this market-wide (and up to 73% of sector-wide) excess square correlation by its positive relation to proxies for information heterogeneity and U.S. monetary and real conditions, and its negative relation to market volatility and the level of the short-term interest rate. This evidence is consistent with the implications of portfolio rebalancing and product market theories of financial contagion, but offers little or no support for the correlated liquidity shock channel.
Shadow education: patterns and scale of private supplementary tutoring in English in secondary education at urban Dhaka in Bangladesh

Abstract Private supplementary tutoring with an additional fee is generally called shadow education, and this has become a common phenomenon in urban Dhaka, where patterns and scale of tutoring in English have been remarkable in recent years. This study used a mixed-methods approach that included quantitative and qualitative data collected from a survey and individual interview. Tutoring in English has been a regular feature of the teaching profession in this urban area. The paper examines various patterns of private tutoring in English and focuses on the amount of tutoring, including the tutoring received and not received by students in urban Dhaka. It shows the variations of scale regarding tutoring in English between male and female students. The study also identifies different types of private tutors who deliver supplementary tutoring. Finally, the choices pupils make regarding their evaluation on the effectiveness of shapes of tutoring in English are discussed.
Bmc Developmental Biology Differential Expression of Wnt4 in Testicular and Ovarian Development in a Marsupial

Background: WNT4 is a key regulator of gonadal differentiation in humans and mice, playing a pivotal role in early embryogenesis. Using a marsupial, the tammar wallaby, in which most gonadal differentiation occurs after birth whilst the young is in the pouch, we show by quantitative PCR during early testicular and ovarian development that WNT4 is differentially expressed ingonads.
Transient Expression of Hemagglutinin Antigen from Low Pathogenic Avian Influenza A (H7N7) in Nicotiana benthamiana

The influenza A virus is of global concern for the poultry industry, especially the H5 and H7 subtypes as they have the potential to become highly pathogenic for poultry. In this study, the hemagglutinin (HA) of a low pathogenic avian influenza virus of the H7N7 subtype isolated from a Swedish mallard Anas platyrhynchos was sequenced, characterized and transiently expressed in Nicotiana benthamiana. Recently, plant expression systems have gained interest as an alternative for the production of vaccine antigens. To examine the possibility of expressing the HA protein in N. benthamiana, a cDNA fragment encoding the HA gene was synthesized de novo, modified with a Kozak sequence, a PR1a signal peptide, a C-terminal hexahistidine (6×His) tag, and an endoplasmic retention signal (SEKDEL). The construct was cloned into a Cowpea mosaic virus (CPMV)-based vector (pEAQ-HT) and the resulting pEAQ-HT-HA plasmid, along with a vector (pJL3:p19) containing the viral gene-silencing suppressor p19 from Tomato bushy stunt virus, was agro-infiltrated into N. benthamiana. The highest gene expression of recombinant plant-produced, uncleaved HA (rHA0), as measured by quantitative real-time PCR was detected at 6 days post infiltration (dpi). Guided by the gene expression profile, rHA0 protein was extracted at 6 dpi and subsequently purified utilizing the 6×His tag and immobilized metal ion adsorption chromatography. The yield was 0.2 g purified protein per kg fresh weight of leaves. Further molecular characterizations showed that the purified rHA0 protein was N-glycosylated and its identity confirmed by liquid chromatography-tandem mass spectrometry. In addition, the purified rHA0 exhibited hemagglutination and hemagglutination inhibition activity indicating that the rHA0 shares structural and functional properties with native HA protein of H7 influenza virus. Our results indicate that rHA0 maintained its native antigenicity and specificity, providing a good source of vaccine antigen to induce immune response in poultry species.
Comparative Statics, Stability, and Uniqueness

Consider an economic model whose equilibrium can be represented as the fixed point of a system of differentiable equations. Using the theory of B-matrices, I show that comparative statics are well-behaved if the interactions between the equations are not too large, and the negative interactions are not too varied. When there are only positive interactions, for example when strategic complements prevail in a strategic setting, I prove a version of Samuleson's (1947) Correspondence Principle in that equilibrium is nondecreasing for any positive parameter shock if and only if equilibrium is exponentially stable under discrete time best reply dynamics . If there are only negative interactions, like when strategic substitutes prevail in a game theoretic context, I use the theory of inverse M-matrices to significantly relax Dixit's (1986) conditions under which comparative statics are well-behaved. For every comparative statics result I show that if the conditions apply globally then equilibrium is unique. Applications are provided to differentiated products Cournot oligopoly, market demand with interdependent preferences, and games on fixed networks.
A Chandra Catalog of X-Ray Sources in the Central 150 pc of the Galaxy

We present the catalog of X-ray sources detected in a shallow Chandra survey of the inner 2° × 0. °8 of the Galaxy and in two deeper observations of the Radio Arches and Sgr B2. The catalog contains 1352 objects that are highly absorbed (NH ≳ 4 × 1022 cm-2) and are therefore likely to lie near the Galactic center (D ≈ 8 kpc), and 549 less absorbed sources that lie within ≲6 kpc of Earth. On the basis of the inferred luminosities of the X-ray sources and the expected numbers of various classes of objects, we suggest that the sources with LX ≲ 1033 ergs s-1 that comprise ≈90% of the catalog are cataclysmic variables and that the ≈100 brighter objects are accreting neutron stars and black holes, young isolated pulsars, and Wolf-Rayet and O (WR/O) stars in colliding-wind binaries. We find that the spatial distribution of X-ray sources matches that of the old stellar population observed in the infrared, which supports our suggestion that most of the X-ray sources are old cataclysmic variables. However, we find that there is an apparent excess of ≈10 bright sources in the Radio Arches region. That region is already known to be the site of recent star formation, so we suggest that the bright sources in this region are young high-mass X-ray binaries, pulsars, or WR/O star binaries. We briefly discuss some astrophysical questions that this catalog can be used to address.
STRING CREATION IN D6-BRANE BACKGROUND

The production of string charge during a crossing of certain oriented D-branes is studied. We compute the string charge in the system of a probe D2-brane and a background D6-brane by using the equations of motion in ten dimensions. We confirm the creation of string charge as inflow from the background D6-brane.
MANAGING FINANCIAL REPORTS OF COMMERCIAL-BANKS - THE INFLUENCE OF TAXES, REGULATORY CAPITAL, AND EARNINGS

This paper examines whether managerial discretion over loan loss accruals, accounting related transactions such as sales of investment securities, and financing transactions are used to manage capital, earnings or taxes. We model discretion over these decisions using a system of five equations generating from an underlying cost minimization problem. The estimated parameters of the system suggest that banks manage both capital and earnings using accounting, investment and financing discretion exercised over these transactions. The framework we use highlights trade-offs among accounting and financing transactions. We find that accounting sources of capital in part determine banks' propensity to issue new securities and that the positive reported capital effects of gains from transactions such as asset sales in part determine managers' willingness to charge-off loans.
Asynchronous group key distribution on top of the cc2420 security mechanisms for sensor networks

A sensor network is a network consisting of small, inexpensive, low-powered sensor nodes that communicate to complete a common task. Sensor nodes are characterized by having limited communication and computation capabilities, energy, and storage. They often are deployed in hostile environments creating a demand for encryption and authentication of the messages sent between them. Due to severe resource constraints on the sensor nodes, efficient key distribution schemes and secure communication protocols with low overhead are desired. In this paper we present an asynchronous group key distribution scheme with no time synchronization requirements. The scheme decreases the number of key updates by providing them on an as needed basis according to the amount of network traffic. We evaluate the CC2420 radio security mechanism and show how to use it as a basis to implement secure group communication using our proposed group key distribution scheme.
Socially Influenced Behaviour and Learning in Locusts

As a part of our research on the evolution of social learning in insects, we examined socially influenced behaviour and social learning in desert locust (Schistocerca gregaria) nymphs and adults. In the nymphs, the only positive effect we documented was an increased tendency to feed while in the company of another locust than alone. The adults, on the other hand, showed significant preference for joining others (local enhancement) in both the contexts of feeding and egg laying. Neither nymphs nor adults, however, showed social learning. Our preliminary analyses pointed to locusts as a likely insect that might possess social learning. Our research, when taken together with research on phase-shifts and swarm ⁄marching behaviour of gregarious locusts, suggests that the behavioural dynamics of gregarious locusts may make local enhancement but not social learning beneficial. The possible difference we documented between the nymphs and adults could enable us to further explore the proximate and ultimate mechanisms that underlie socially influenced behaviour.
From deterministic world view to uncertainty and fuzzy logic: a critique of artificial intelligence and classical logic

The purpose of this paper is to show paradigm shift about mechanistic and deterministic world view or thinking that it has been a dominant role over centuries. This view is based on three columns: First, Aristotelian Logic which it has nearly ruled for twenty three centuries. Second is Newtonian Mechanics and Cartesian Dualism. Third Determinism, which has been transformed Uncertainty in the 20th century. The central theme of this paper is Critique of Classical Logic, Cartesian Dualism and Artificial Intelligence. Finally we will show that natural thinking and system would be ruled in the next century: Fuzzy World or Fuzzy Logic.
QAM and PSK codebooks for limited feedback MIMO beamforming

This paper considers the problem of beamforming in multiple-input multiple-output (MIMO) wireless systems. Assuming perfect channel state information at the receiver, the choice of the beamforming vector is made possible through a noiseless limited-rate feedback of one or more bits per coefficient to the transmitter. This paper proposes the use of beamforming codebooks based on quadrature amplitude modulation (QAM) and phase-shift keying (PSK) constellations, which essentially eliminates the need for storage of the codebook. We show that such codebooks perform arbitrarily close to the perfect feedback case as the constellation size increases, and that full diversity order is achieved. We demonstrate an equivalence between the beamforming codebook search problem with that of noncoherent sequence detection. Based on this we propose fast beamforming vector search algorithms. Monte-Carlo simulations are presented to show that the performance is comparable to the best known codebooks, and that the search complexity can be reduced by several orders of magnitude.
Power spectrum of out-of-equilibrium forces in living cells: amplitude and frequency dependence

Living cells exhibit an important out-of-equilibrium mechanical activity, mainly due to the forces generated by molecular motors, acting individually or collectively on the cytoskeleton. They contribute to the fact that the fluctuation-dissipation theorem does not apply in living systems. In this work we probe the cytoskeletal out-of-equilibrium dynamics by performing simultaneous active and passive microrheology experiments, using the same micron-sized probe specifically bound to the actin cortex. The free motion of the probe exhibits a constrained, subdiffusive behavior at short time scales (t < 2s), and a directed, superdiffusive behavior at larger time scales, while, in response to a step force, its creep function presents the usual weak power law dependence with time. Combining the results of both experiments, we precisely measure for the first time the power spectrum of the force fluctuations exerted on this probe, which lies more than one order of magnitude above the spectrum expected at equilibrium, and greatly depends on frequency. We retrieve an effective temperature Teff of the system, as an estimate of the departure from thermal equilibrium. This departure is especially pronounced for long time scales, where Teff bears the footprint of the cooperative activity of motors pulling on the actin network. ATP depletion reduces the fluctuating force amplitude and results in a sharp decrease of Teff towards equilibrium.
Detection of Harassment on Web 2.0

Web 2.0 has led to the development and evolution of web-based communities and applications. These communities provide places for information sharing and collaboration. They also open t he door for inappropriate online activities, such as harassment, i n which some users post messages in a virtual community that are intention- ally offensive to other members of the community. It is a new and challenging task to detect online harassment; currently fe w systems attempt to solve this problem. In this paper, we use a supervised learning approach for dete ct- ing harassment. Our technique employs content features, sentiment features, and contextual features of documents. The experi mental results described herein show that our method achieves significant improvements over several baselines, including Term Frequency- Inverse Document Frequency (TFIDF) approaches. Identifica tion of online harassment is feasible when TFIDF is supplemented with sentiment and contextual feature attributes.
The multiplicity of emotions: A framework of emotional functions in decision making

A four-fold classification of emotions with respect to their functions in decision making is proposed. It is argued that emotions are not homogenous concerning their role in decision making, but that four distinct functions can be distinguished concerning emotional phenomena. One function is to provide information about pleasure and pain for preference construction, a second function is to enable rapid choices under time pressure, a third function is to focus attention on relevant aspects of a decision problem, and a fourth function is to generate commitment concerning morally and socially significant decisions. The pertinent literature on the relationship between emotion and decision making is reviewed, and it is concluded that most approaches fit into the proposed framework. We argue that a precise conceptualization of emotional phenomena is required to advance our understanding of the complex role of emotions in decision making.
A Functional Magnetic Resonance Imaging Assessment of Small Animals’ Phobia Using Virtual Reality as a Stimulus

Background To date, still images or videos of real animals have been used in functional magnetic resonance imaging protocols to evaluate the brain activations associated with small animals’ phobia. Objective The objective of our study was to evaluate the brain activations associated with small animals’ phobia through the use of virtual environments. This context will have the added benefit of allowing the subject to move and interact with the environment, giving the subject the illusion of being there. Methods We have analyzed the brain activation in a group of phobic people while they navigated in a virtual environment that included the small animals that were the object of their phobia. Results We have found brain activation mainly in the left occipital inferior lobe (P<.05 corrected, cluster size=36), related to the enhanced visual attention to the phobic stimuli; and in the superior frontal gyrus (P<.005 uncorrected, cluster size=13), which is an area that has been previously related to the feeling of self-awareness. Conclusions In our opinion, these results demonstrate that virtual stimulus can enhance brain activations consistent with previous studies with still images, but in an environment closer to the real situation the subject would face in their daily lives.
Topic Introduction In Vitro Investigation of Synaptic Plasticity

Therese Abrahamsson,1,4 Txomin Lalanne,1,2,4 Alanna J. Watt,3 and P. Jesper Sjöström1,5 Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montréal General Hospital, Montréal, Québec H3G 1A4, Canada; Integrated Program in Neuroscience, McGill University, Montréal, Quebec H3A 2B4, Canada; Department of Biology, Bellini Life Sciences Building, McGill University, Montréal, Québec H3G 0B1, Canada