Miracle-dz/UniFAR-FTUs huggingface dataset:
Mathematics of operations research

We study stochastic teams (known also as decentralized stochastic control problems or identical interest stochastic dynamic games) with large or countably in ﬁ nite numbers of decision makers and characterize the existence and structural properties of (globally) optimal policies. We consider both static and dynamic nonconvex teams where the cost function and dynamics satisfy an exchangeability condition. To arrive at existence and structural results for optimal policies, we ﬁ rst introduce a topology on control policies, which involves various relaxations given the decentralized information structure. This is then utilized to arrive at a de Finetti – type representation theorem for exchangeable policies. This leads to a representation theorem for policies that admit an in ﬁ nite exchangeability condition. For a general setup of stochastic team problems with N decision makers, under exchangeability of observations of decision makers and the cost function, we show that, without loss of global optimality, the search for optimal policies can be restricted to those that are N -exchangeable. Then, by extending N -exchangeable policies to in ﬁ nitely exchangeable ones, establishing a convergence argument for the induced costs, and using the presented de Finetti – type theorem, we establish the existence of an optimal decentralized policy for static and dynamic teams with countably in ﬁ nite numbers of decision makers, which turns out to be symmetric (i.e., identical) and randomized. In particular, unlike in prior work, convexity of the cost in policies is not assumed. Finally, we show the near optimality of symmetric independently randomized policies for ﬁ nite N -decision-maker teams and thus establish approximation results for N -decision-maker weakly coupled stochastic teams.
MAC throughput analysis of HomePlug 1.0

Power line communication technology is one of the most tractable home-networking technologies, because existing power line facilities can be utilized for data communications without deploying any new physical links. Although HomePlug 1.0, the power line communication standard, has undergone field trials and simulations, its analytic model and performance was not presented. In this letter, we analyze the performance of HomePlug 1.0 in terms of saturation throughput.
Optimized activation of the primary sensorimotor cortex for clinical functional MR imaging.

BACKGROUND AND PURPOSE One application of functional MR imaging is to identify the primary sensorimotor cortex (M1 and S1) around the central sulcus before brain surgery. However, it has been shown that undesirable coactivation of nonprimary motor areas, such as the supplementary motor area and the premotor area, can interfere with the identification of the primary motor cortex, especially in patients with distorted anatomic landmarks. We therefore sought to design a simple functional MR imaging paradigm for selective activation of the primary sensorimotor cortex. METHODS Different paradigms using finger tapping for motor activation were examined and compared with respect to the distribution of activated voxels in primary and nonprimary cortical areas. Studies were conducted in 14 healthy volunteers using a blood oxygen level-dependent multislice echo-planar imaging sequence. RESULTS The most selective activation of the primary sensorimotor cortex was obtained with a paradigm combining right-sided finger tapping as the activation condition with left-sided finger tapping as the control condition. Analysis of the signal time course of primary and nonprimary areas revealed that the highly selective primary motor activation was due to it being restricted to contralateral finger movements, as opposed to the nonprimary motor areas, which were activated by ipsilateral, contralateral, and bilateral finger movements alike. CONCLUSION When performing functional MR imaging to determine the location of the primary sensorimotor cortex, one should compare unilateral voluntary movements as the activation condition with contralateral movements as the control condition to accentuate activation of the primary motor area and to suppress undesirable coactivation of nonprimary motor areas.
Distribution, ultrastructure, and connectivity of calretinin‐immunoreactive mossy cells of the mouse dentate gyrus

Hilar mossy cells of the mouse were shown recently to display calretinin immunoreactivity (Liu et al. [1996] Exp Brain Res 108:389–403). The morphological and connectional characteristics of these cells are poorly understood. In the present study, we used immunohistochemical, electron microscopic, and neuronal tracing techniques to describe their distribution, morphology, and connectivity.
A model for sidewall adhesions in the rabbit: Reduction by an absorbable barrier

Despite use of surgical adjuvants, pelvic adhesions frequently develop following infertility surgery. Recently a resorbable biocompatible material, TC 7, has been designed to be used as a barrier to reduce adhesion formation. Reproducibly severe sidewall adhesions were only able to be created in one of six models tested. The model consisted of the following steps: excision of a full thickness 2 × 2‐cm musculoperitoneal tissue mass, scraping of an adjacent 2cm length of uterine horn, tamponading of all bleeding, and suturing (6‐0 Vicryl) of normal tube and sidewall so as to directly approximate the traumatized tissues. Studies were conducted in 13 rabbits after creation of the bilateral sidewall and horn lesions, each serving as its own control. Choice of control and TC 7 sides was determined randomly. Adhesion formation was examined 2 weeks postoperatively. No residual material was noted at that time. Adhesion scores were the composite total of extent (0–4), type (0–4), and tenacity (0–3) of sidewall adhesions, and were significantly reduced on the TC 7 side as compared with the control side (mean 6.8 ± 0.4 vs 9.0 ± 0.3, median 6 vs 9, sign test P = 0.0032). No complications of use of the barrier were noted. It is concluded that use of TC 7, a resorbable biocompatible barrier, was able to significantly reduce postoperative adhesion formation on the rabbit sidewall.
Incremental Learning for Fine-Grained Image Recognition

This paper considers the problem of fine-grained image recognition with a growing vocabulary. Since in many real world applications we often have to add a new object category or visual concept with just a few images to learn from, it is crucial to develop a method that is able to generalize the recognition model from existing classes to new classes. Deep convolutional neural networks are capable of constructing powerful image representations; however, these networks usually rely on a logistic loss function that cannot handle the incremental learning problem. In this paper, we present a new method that can efficiently learn a new class given only a limited number of training examples, which we evaluate on the problems of food and clothing recognition. To illustrate the performance of our proposed method on the task of recognizing different kinds of food, when using only 1.3\% of training examples per category we achieved about 73\% of the performance (as measured by F1-score) compared to when using all available training data.
High levels of genetic recombination among cotransfected plasmid DNAs in poxvirus-infected mammalian cells

The frequency of recombination between transfected plasmid DNAs was measured by using cultured cells infected with a variety of poxviruses. Plasmid derivatives of pBR322 containing XhoI linker insertion mutations in the tetracycline gene were used to assess recombination frequencies in rabbit cells infected with the leporipoxviruses Shope fibroma virus and myxoma virus and the orthopoxvirus vaccinia virus. Recombination frequencies were calculated by Southern blotting, which detects novel plasmid restriction fragments generated by genetic recombination, and by a plasmid rescue procedure in which the reconstruction of an intact tetracycline gene in the transfected rabbit cell was monitored by transformation back into Escherichia coli. The highest recombination frequencies were measured in cells infected with Shope fibroma virus and myxoma virus, and a minimum recombination frequency of at least one recombination event per 7 kilobases was calculated within 24 h posttransfection under these conditions. The deduced recombination frequency in vaccinia virus-infected cells was at least fivefold lower and was not detectable in mock-infected cells, suggesting that the induced recombination activity detected by these methods was under viral control. The results of kinetic studies, analysis with methylation-sensitive restriction enzymes, and the use of phosphonoacetic acid, a specific inhibitor of poxvirus DNA polymerase, indicated that recombination between transfecting DNAs occurred concomitantly with DNA replication but that the two processes could be partially uncoupled. We conclude that the dramatic expansion of recombination activities in the cytoplasm of poxvirus-infected cells is virus specific and offers a good model system with which to analyze the mechanism of recombination in a eucaryotic environment.
Blogs, wikis and social networking sites: a cross institutional survey amongst Greek students

In this paper, we attempt to explore the penetration of Web 2.0 technologies amongst Greek students, determine their level of usage and explore the students' opinions and perceptions regarding their usefulness for learning and educational purposes. In that context, we present the initial results of a survey-based cross-institutional study, conducted between September 15 and October 30, 2010, on a sample of five hundred undergraduate students from the two oldest university establishments in Greece. Our survey results reveal that social networking sites despite being by far, the most popular Web 2.0 service amongst Greek students, present the lowest perceived value in regards of the service's usefulness for educational and studying support purposes. On the other hand, blogs and wikis, which are considered educationally more useful by students, present low percentages of systematic use and content contribution and even lower percentages of ownership. Following the initial descriptive analysis of our cross institutional survey data presented in this paper, we are in the process of conducting a series of statistical tests for identifying significant correlations between variables and testing a set of prescribed research hypotheses.
Review of imaging network activities in developing rodent cerebral cortex in vivo

Abstract. The combination of voltage-sensitive dye imaging (VSDI) with multielectrode array (MEA) recordings in the rodent cerebral cortex in vivo allows the simultaneous analysis of large-scale network interactions and electrophysiological single-unit recordings. Using this approach, distinct patterns of spontaneous and sensory-evoked activity can be recorded in the primary somatosensory (S1) and motor cortex (M1) of newborn rats. Already at the day of birth, gamma oscillations and spindle bursts in the barrel cortex synchronize the activity of a local columnar ensemble, thereby generating an early topographic representation of the sensory periphery. During the first postnatal week, both cortical activity patterns undergo developmental changes in their spatiotemporal properties and spread into neighboring cortical columns. Simultaneous VSDI and MEA recordings in S1 and M1 demonstrate that the immature motor cortex receives information from the somatosensory system and that M1 may trigger movements of the periphery, which subsequently evoke gamma oscillations and spindle bursts in S1. These early activity patterns not only play an important role in the development of the cortical columnar architecture, they also control the ratio of surviving versus dying neurons in an activity-dependent manner, making these processes most vulnerable to pathophysiological disturbances during early developmental stages.
The Potential for Bioenergy Crop Production in Baden-Wuerttemberg: An Application of EPIC and GIS to Bioenergy Modeling

Greenhouse gas emissions resulting from burning fossil fuels are affecting the climate of our planet. In order to abate this climate change, changes have to be made in the systems of energy production. Sustainable use of bioenergy causes no net emissions of CO2 and can also help to reduce the emissions of NOx. The issue has also political relevance, as the European Union has made political commitments to meet 15% of its real primary energy demand using renewable sources by 2010. This study examines the usability of the EPIC model (Environmental Policy Integrated Climate) and Geographic Information Systems (GIS) methods to estimate the potentials of bioenergy crop production in Baden-Wuerttemberg. The productivity estimates for different areas given by the model are distributed spatially over the study area. Productivities of different species and management options in different areas are compared. Also the use of other suitability aspects (agricultural productivity, production costs) in estimating real potentials is examined. Based on the results, the usability of this methodology on a European scale is discussed.
Paleoseismological evidence of surface faulting along the northeastern Himalayan front, India: Timing, size, and spatial extent of great earthquakes

The similar to 2500 km long Himalayan arc has experienced three large to great earthquakes of M-w 7.8 to 8.4 during the past century, but none produced surface rupture. Paleoseismic studies have been conducted during the last decade to begin understanding the timing, size, rupture extent, return period, and mechanics of the faulting associated with the occurrence of large surface rupturing earthquakes along the similar to 2500 km long Himalayan Frontal Thrust (HFT) system of India and Nepal. The previous studies have been limited to about nine sites along the western two-thirds of the HFT extending through northwest India and along the southern border of Nepal. We present here the results of paleoseismic investigations at three additional sites further to the northeast along the HFT within the Indian states of West Bengal and Assam. The three sites reside between the meizoseismal areas of the 1934 Bihar-Nepal and 1950 Assam earthquakes. The two westernmost of the sites, near the village of Chalsa and near the Nameri Tiger Preserve, show that offsets during the last surface rupture event were at minimum of about 14 m and 12 m, respectively. Limits on the ages of surface rupture at Chalsa (site A) and Nameri (site B), though broad, allow the possibility that the two sites record the same great historical rupture reported in Nepal around A.D. 1100. The correlation between the two sites is supported by the observation that the large displacements as recorded at Chalsa and Nameri would most likely be associated with rupture lengths of hundreds of kilometers or more and are on the same order as reported for a surface rupture earthquake reported in Nepal around A.D. 1100. Assuming the offsets observed at Chalsa and Nameri occurred synchronously with reported offsets in Nepal, the rupture length of the event would approach 700 to 800 km. The easternmost site is located within Harmutty Tea Estate (site C) at the edges of the 1950 Assam earthquake meizoseismal area. Here the most recent event offset is relatively much smaller (<2.5 m), and radiocarbon dating shows it to have occurred after A.D. 1100 (after about A.D. 1270). The location of the site near the edge of the meizoseismal region of the 1950 Assam earthquake and the relatively lesser offset allows speculation that the displacement records the 1950 M-w 8.4 Assam earthquake. Scatter in radiocarbon ages on detrital charcoal has not resulted in a firm bracket on the timing of events observed in the trenches. Nonetheless, the observations collected here, when taken together, suggest that the largest of thrust earthquakes along the Himalayan arc have rupture lengths and displacements of similar scale to the largest that have occurred historically along the world's subduction zones.
Incidence of sperm chromosomal abnormalities in a risk population: relationship with sperm quality and ICSI outcome.

BACKGROUND An increased incidence of chromosome abnormalities has been reported in sperm samples of many infertile men by fluorescence in-situ hybridization (FISH). METHODS Sperm aneuploidy and diploidy rates for chromosomes 13, 18, 21, X and Y were evaluated in 63 patients with normal karyotypes using dual and triple-colour FISH techniques. Indications for sperm FISH analysis were: recurrent miscarriages of unknown aetiology (RM, n = 40), repeated implantation failure after intracytoplasmic sperm injection (ICSI) (IF, n = 19), previous Down's syndrome pregnancies (n = 3), and meiotic abnormalities (MA, n = 1). Nine healthy normozoospermic donors were also evaluated as a control group. RESULTS A significant increase in the incidence of sex chromosome disomies was found in the RM, IF and MA groups. Oligoasthenoteratozoospermic patients (n = 21) showed significantly higher rates of diploidy and disomies for sex chromosomes and chromosomes 18 and 21 than normozoospermic patients (n = 14). Thirty-one patients with normal and seven with abnormal FISH results had undergone several ICSI treatments (108 and 23 cycles respectively). Couples with abnormal sperm FISH results showed decreased pregnancy and implantation rates and increased miscarriage rates. CONCLUSIONS Patients with a clinical background of recurrent miscarriages of unknown aetiology or implantation failure after ICSI are at risk of showing sperm chromosomal abnormalities, the incidence of which is higher in oligoasthenoteratozoospermic patients.
XMM-Newton observations of HESS J1813-178 reveal a composite Supernova remnant

Aims--We present X-ray and {sup 12}CO(J=1-0) observations of the very-high-energy (VHE) {gamma}-ray source HESS J1813-178 with the aim of understanding the origin of the {gamma}-ray emission. Methods--High-angular resolution X-ray studies of the VHE {gamma}-ray emission region are performed using 18.6 ks of XMM-Newton data, taken on HESS J1813-178 in October 2005. Using this dataset we are able to undertake spectral and morphological studies of the X-ray emission object with greater precision than previous studies. NANTEN {sup 12}CO(J=1-0) data are used to search for correlations of the {gamma}-ray emission with molecular clouds which could act as target material for {gamma}-ray production in a hadronic scenario. Results--The NANTEN {sup 12}CO(J=1-0) observations show a giant molecular cloud of mass 2.5 x 10{sup 5} M{sub {circle_dot}} at a distance of 4 kpc in the vicinity of HESS J1813-178. Even though there is no direct positional coincidence, this giant cloud might have influenced the evolution of the {gamma}-ray source and its surroundings. The X-ray data show a highly absorbed (n{sub H} {approx} 1 x 10{sup 23} cm{sup -2}) non-thermal X-ray emitting object coincident with the previously known ASCA source AXJ1813-178 showing a compact core and an extended tail towards the north-east, located in the center of the radio shell-type Supernova remnant (SNR) G12.82-0.2. This central object shows morphological and spectral resemblance to a Pulsar Wind Nebula (PWN) and we therefore consider that this object is very likely to be a composite SNR. Nevertheless, we cannot distinguish between the scenarios in which the {gamma}-rays originate in the shell of the SNR and the one in which they originate in the central object. We discuss both scenarios in terms of a one-zone leptonic model and demonstrate, that in order to connect the core X-ray emission to the VHE {gamma}-ray emission electrons have to be accelerated to energies of at least 1 PeV. We conclude that if indeed the X-rays are connected to the VHE {gamma}-rays HESS J1813-178 has to be a Galactic Pevatron.
Documents de Travail du Centre d ’ Economie de la Sorbonne Heterogeneous Firms , “ Profit Shifting ” FDI and International Tax Competition

Larger firms are more likely to use tax haven operations to exploit international tax differences. We study a tax game between a large country and a tax haven modeling heterogeneous monopolistic firms, which can shift profits abroad. We show that a higher degree of firm heterogeneity (a mean-preserving spread of the cost distribution) increases the degree of tax competition, i.e. it decreases the equilibrium tax rate of the large country, leads to higher outflows of its tax base and thus decreases its equilibrium tax revenue. Similar effects hold for a higher substitutability across varieties. We find that models with homogeneous firms understate the strength of tax competition. JEL: F23, H25, H87
The influence of p53 mutation status on the anti-cancer effect of cisplatin in oral squamous cell carcinoma cell lines

Objectives The purpose of this study was to evaluate the anti-cancer activity of cisplatin by studying its effects on cell viability and identifying the mechanisms underlying the induction of cell cycle arrest and apoptosis on oral squamous cell carcinoma (OSCC) cell lines with varying p53 mutation status. Materials and Methods Three OSCC cell lines, YD-8 (p53 point mutation), YD-9 (p53 wild type), and YD-38 (p53 deletion) were used. To determine the cytotoxic effect of cisplatin, MTS assay was performed. The cell cycle alteration and apoptosis were analyzed using flow cytometry. Western blot analysis was used to detect the expression of cell cycle alteration- or apoptosis-related proteins as well as p53. Results Cisplatin showed a time- and dose-dependent anti-proliferative effect in all cell lines. Cisplatin induced G2/M cell accumulation in the three cell lines after treatment with 0.5 and 1.0 µg/mL of cisplatin for 48 hours. The proportion of annexin V-FITC-stained cells increased following treatment with cisplatin. The apoptotic proportion was lower in the YD-38 cell line than in the YD-9 or YD-8 cell lines. Also, immunoblotting analysis indicated that p53 and p21 were detected only in YD-8 and YD-9 cell lines after cisplatin treatment. Conclusion In this study, cisplatin showed anti-cancer effects via G2/M phase arrest and apoptosis, with some difference among OSCC cell lines. The mutation status of p53 might have influenced the difference observed among cell lines. Further studies on p53 mutation status are needed to understand the biological behavior and characteristics of OSCCs and to establish appropriate treatment.