Miracle-dz/UniFAR-FTUs huggingface dataset:
Fitting mixtures of exponentials to long-tail distributions to analyze network performance models

Traffic measurements from communication networks have shown that many quantities characterizing network performance have long-tail probability distributions, i.e., with tails that decay more slowly than exponentially. Long-tail distributions can have a dramatic effect upon performance, but it is often difficult to describe this effect in detail, because performance models with component long-tail distributions tend to be difficult to analyze. We address this problem by developing an algorithm for approximating a long-tail distribution by a finite mixture of exponentials. The fitting algorithm is recursive over time scales. At each stage, an exponential component is fit in the largest remaining time scale and then the fitted exponential component is subtracted from the distribution. Even though a mixture of exponentials has an exponential tail, it can match a long-tail distribution in the regions of primary interest when there are enough exponential components.
Effectiveness of nurse delivered endoscopy: findings from randomised multi-institution nurse endoscopy trial (MINuET)

Objective To compare the clinical effectiveness of doctors and nurses in undertaking upper and lower gastrointestinal endoscopy. Design Pragmatic trial with Zelen’s randomisation before consent to minimise distortion of existing practice. Setting 23 hospitals in the United Kingdom. In six hospitals, nurses undertook both upper and lower gastrointestinal endoscopy, yielding a total of 29 centres. Participants 67 doctors and 30 nurses. Of 4964 potentially eligible patients, we randomised 4128 (83%) and recruited 1888 (38%) from July 2002 to June 2003. Interventions Diagnostic upper gastrointestinal endoscopy and flexible sigmoidoscopy, undertaken with or without sedation, with the standard preparation, techniques, and protocols of participating hospitals. After referral for either procedure, patients were randomised between doctors and nurses. Main outcome measures Gastrointestinal symptom rating questionnaire (primary outcome), gastrointestinal endoscopy satisfaction questionnaire and state-trait anxiety inventory (all analysed by intention to treat); immediate and delayed complications; quality of examination and corresponding report; patients’ preferences for operator; and new diagnoses at one year (all analysed according to who carried out the procedure). Results There was no significant difference between groups in outcome at one day, one month, or one year after endoscopy, except that patients were more satisfied with nurses after one day. Nurses were also more thorough than doctors in examining the stomach and oesophagus. While quality of life scores were slightly better in patients the doctor group, this was not statistically significant. Conclusions Diagnostic endoscopy can be undertaken safely and effectively by nurses. Trial registration International standard RCT 82765705
Associations of Moderate to Severe Asthma with Obstructive Sleep Apnea

Purpose This study aimed to evaluate the correlation between associating factors of moderate to severe asthma with obstructive sleep apnea (OSA). Materials and Methods One hundred and sixty-seven patients who visited the pulmonary and sleep clinic in Severance Hospital presenting with symptoms of sleep-disordered breathing were evaluated. All subjects were screened with ApneaLink. Thirty-two subjects with a high likelihood of having OSA were assessed with full polysomnography (PSG). Results The mean age was 58.8±12.0 years and 58.7% of subjects were male. The mean ApneaLink apnea-hypopnea index (AHI) was 12.7±13.0/hr. The mean ApneaLink AHI for the 32 selected high risk patients of OSA was 22.3±13.2/hr, which was lower than the sleep laboratory-based PSG AHI of 39.1±20.5/hr. When OSA was defined at an ApneaLink AHI ≥5/hr, the positive correlating factors for OSA were age, male gender, and moderate to severe asthma. Conclusion Moderate to severe asthma showed strong correlation with OSA when defined at an ApneaLink AHI ≥5/hr.
A Microeconomic Model for Hierarchical Bandwidth Sharing in Dynamic Spectrum Access Networks

We consider the problem of hierarchical bandwidth sharing in dynamic spectrum access (or cognitive radio) environment. In the system model under consideration, licensed service (i.e., primary service) can share/sell its available bandwidth to an unlicensed service (i.e., secondary service), and again, this unlicensed service can share/sell its allocated bandwidth to other services (i.e., tertiary and quaternary services). We formulate the problem of hierarchical bandwidth sharing as an interrelated market model used in microeconomics for which a multiple-level market is established among the primary, secondary, tertiary, and quaternary services. We use the concept of demand and supply functions to obtain the equilibrium at which all the services are satisfied with the amount of allocated bandwidth and the price. These demand and supply functions are derived based on the utility of the connections using the different services (i.e., primary, secondary, tertiary, and quaternary services). For distributed implementation of the hierarchical bandwidth sharing model in a system in which global information is not available, iterative algorithms are proposed through which each service adapts its strategies to reach the equilibrium. The system stability condition is analyzed for these algorithms. Finally, we demonstrate the application of the proposed model to achieve dynamic bandwidth sharing in an integrated WiFi-WiMAX network.
Availability-Aware Virtual Network Embedding for Multi-tier Applications in Cloud Networks

There is a growing trend for service providers (SPs) to migrate their multi-tier applications from local clusters to public cloud networks. In the cloud environment, it is a great concern of SPs to improve the availability of their virtual networks, in addition to guarantees of their virtual resource requirements, such as VMs and bandwidth. However, meeting these requirements results in an inefficient utilization of physical resources, which goes against the operational goal of cloud providers. To address this challenge, in this paper, we propose an availability-aware virtual network embedding framework that simultaneously improves the availability of virtual networks and the resource efficiency. We first propose a new metric to quantify the availability cost of a multi-tier virtual network, and then formulate the embedding problem as a joint optimization of the aggregated bandwidth and availability costs. Due to the NP-hardness of the embedding problem, we devise a heuristic algorithm that can solve the problem in polynomial time. Extensive simulation results show that the proposed algorithm enables CP to achieve various trade-offs between resource efficiency and availability, and to gain more revenue (e.g., 16.1% under a datacenter load of 80%) than the availability-agonistic algorithm.
Benchmarking the Grasping Capabilities of the iCub Hand With the YCB Object and Model Set

The letter reports an evaluation of the iCub grasping capabilities, performed using the YCB Object and Model Set. The goal is to understand what kind of objects the iCub dexterous hand can grasp, and with what degree of robustness and flexibility, given the best possible control strategy. Therefore, the robot fingers are directly controlled by a human expert using a dataglove: in other words, the human brain is employed as the best possible controller. Through this technique, we provide a baseline for researchers who want to evaluate the performance of their grasping controller. By using a widespread robotic platform and a publicly available set of objects, we believe that many researchers can directly benefit from this resource; moreover, what we propose is a general methodology for benchmarking of grasping and manipulation that can be applied to any dexterous robotic hand.
NPSNET:A Network Software Architecture for LargeScale Virtual Environments

This paper explores the issues involved in designing and developing network software architectures for large-scale virtual environments. We present our ideas in the context of NPSNET-IV, the first 3-D virtual environment that incorporates both the IEEE 1278 distributed interactive simulation (DIS) application protocol and the IP multicast network protocol for multiplayer simulation over the Internet.
A Faster Algorithm for Enumerating Connected Convex Subgraphs in Acyclic Digraphs

Subgraph enumeration is one of the most crucial steps involved in the custom instruction identification for application-specific instruction set processors. Generating all connected convex subgraphs from an acyclic digraph is a computationally difficult problem. In this letter, we propose a simple and fast algorithm for enumerating all connected convex subgraphs in acyclic digraphs. Experimental results show that our algorithm outperforms the latest algorithm in the literature. We also present a parallel approach for enumerating all connected convex subgraphs using MapReduce. Results for real world benchmarks covering different application domains reveal that the parallel approach can achieve near linear speedup over the sequential approach.
Development and repair of experimental pressure ulcers in the rat abdominal wall induced by repeated compression using magnets

of the skin proceeded to full-thickness necrosis and/or discoloration throughout or in part of the compressed area. Necrotic skin was replaced by black/brown eschar, accompanying exudation, and signiﬁcant tissue hardening. The injuries considerably contracted a few days after completing the series of compressions. The eschar further decreased gradually in size and usually became detached with time, after which a skin ulcer formed. A small number of rats showed only erosion and/or severe redness of the skin, damage which was reversible to heal without eschar formation. Generally, skin injuries seemed most severe a few days after 5 compressions and essentially healed over the subsequent 20 days. This model should prove useful for developing preventive measures and treating pressure ulcers. Summary. A better understanding of pressure ulcers requires animal models under precise experimental conditions. We here report on an improved and clinically more relevant model of pressure ulcers. Rats underwent implantation of a gold-plated magnet (25 × 20 × 2 mm) into their peritoneal cavities under anesthesia. At either 3 or 4 days postoperatively, the rat abdominal wall was repeatedly compressed at 100 mmHg (13.3 kPa) for 4 h daily for 5 consecutive days by applying another magnet to the skin while animals were conscious. The rats were reared without further treatment and the abdominal skin was photographed daily. Specimens were removed at appropriate intervals for histological examination. Edema and mild redness of the skin appeared at 1 day after the first compression. After a few repetitions of compression, edema and redness of the skin were enhanced. Subsequently, in the majority of rats, redness
OutRandom: addressing an underrated skill

This paper describes the concept, design and results of a computer game that addresses human's ability to produce random binary sequences. The game was realized in the form of an interactive installation and featured at several events. Because of its inherent motivational characteristics, it is well suited for scientific research on the production and assessment of randomness by humans.
Recurrent Seasonal Variations in Abundance and Composition of Filamentous SOL Cluster Bacteria (Saprospiraceae, Bacteroidetes) in Oligomesotrophic Lake Mondsee (Austria)

ABSTRACT The spatial and temporal variation of SOL cluster bacteria was assessed in oligomesotrophic Lake Mondsee and adjacent lakes by fluorescence in situ hybridization over two annual cycles. The filamentous SOL bacteria were present in Lake Mondsee throughout the study period, and the seasonal dynamics of the SOL community were remarkably similar with respect to both abundance and composition in the two consecutive years. Only two of the three SOL subclusters were detected in Lake Mondsee and four connected lakes. These two populations significantly differed in size distribution and demonstrated pronounced but recurrent differences in seasonality and length of period of appearance in Lake Mondsee. Extensive sampling of the lakes in September 2003 revealed low horizontal variation in the composition of the SOL community within Lake Mondsee but marked variations with depth. Between connected habitats pronounced differences in the composition and abundance of the SOL community were detected. The interaction of SOL bacteria with bacterivorous protists, mesozooplankton, and phytoplankton was investigated in order to reveal variables controlling the structure and dynamics of SOL communities. No strong indication for a bottom-up influence of phytoplankton was found, while the estimated community grazing rates of mesozooplankton on SOL bacteria indicated a top-down control of SOL abundance during mesozooplankton peaks in spring and early autumn. Furthermore, species-specific differences in grazing of mesozooplankton on SOL bacteria were observed. In general, the overall composition of SOL communities was controlled by abiotic factors (water chemistry), while their dynamics seemed to be controlled by abiotic and biotic interactions.
Vestibular Heading Discrimination and Sensitivity to Linear Acceleration in Head and World Coordinates

Effective navigation and locomotion depend critically on an observer's ability to judge direction of linear self-motion, i.e., heading. The vestibular cue to heading is the direction of inertial acceleration that accompanies transient linear movements. This cue is transduced by the otolith organs. The otoliths also respond to gravitational acceleration, so vestibular heading discrimination could depend on (1) the direction of movement in head coordinates (i.e., relative to the otoliths), (2) the direction of movement in world coordinates (i.e., relative to gravity), or (3) body orientation (i.e., the direction of gravity relative to the otoliths). To quantify these effects, we measured vestibular and visual discrimination of heading along azimuth and elevation dimensions with observers oriented both upright and side-down relative to gravity. We compared vestibular heading thresholds with corresponding measurements of sensitivity to linear motion along lateral and vertical axes of the head (coarse direction discrimination and amplitude discrimination). Neither heading nor coarse direction thresholds depended on movement direction in world coordinates, demonstrating that the nervous system compensates for gravity. Instead, they depended similarly on movement direction in head coordinates (better performance in the horizontal plane) and on body orientation (better performance in the upright orientation). Heading thresholds were correlated with, but significantly larger than, predictions based on sensitivity in the coarse discrimination task. Simulations of a neuron/anti-neuron pair with idealized cosine-tuning properties show that heading thresholds larger than those predicted from coarse direction discrimination could be accounted for by an amplitude–response nonlinearity in the neural representation of inertial motion.
FATE OF ANTIGEN-BINDING CELLS IN UNRESPONSIVE AND IMMUNE MICE

Antigen-binding cells (ABC) to the antigen human gamma globulin (HGG) were quantitated in lymphoid tissues of A/J mice at various times after the injection of deaggregated HGG (tolerogen), aggregated HGG (immunogen), or saline. The reaction of lymphoid cells with highly labeled HGG was specific to that antigen since binding could be inhibited by excess unlabeled HGG, but not by unrelated non-cross-reacting proteins. Compared with normal mice, there was a marked decrease in the numbers of ABC in the spleens of unresponsive animals evident as early as 12 h after the injection of tolerogen. A marked increase in ABC was observed in the spleens of immunogen-injected mice, beginning at 24 h and reaching a peak at 3 days. In bone marrow, no difference in the number of ABC was found among the three experimental groups until day 20, when a reduction in ABC was observed only in tolerogen-injected mice. No quantitative difference in the thymuses in the experimental groups could be determined because of the paucity of ABC displayed by normal thymus cells.
A Brief Review of Visualization Techniques for Nerve Tissue Engineering Applications

In nerve tissue engineering, scaffolds act as carriers for cells and biochemical factors and as constructs providing appropriate mechanical conditions. During nerve regeneration, new tissue grows into the scaffolds, which degrade gradually. To optimize this process, researchers must study and analyze various morphological and structural features of the scaffolds, the ingrowth of nerve tissue, and scaffold degradation. Therefore, visualization of the scaffolds as well as the generated nerve tissue is essential, yet challenging Visualization techniques currently used in nerve tissue engineering include electron microscopy, confocal laser scanning microscopy (CLSM), and micro-computed tomography (micro-CT or μCT). Synchrotron-based micro-CT (SRμCT) is an emerging and promising technique, drawing considerable recent attention. Here, we review typical applications of these visualization techniques in nerve tissue engineering. The promise, feasibility, and challenges of SRμCT as a visualization technique applied to nerve tissue engineering are also discussed.
Effects of Admission Hyperglycemia on Stroke Outcome in Reperfused Tissue Plasminogen Activator–Treated Patients

Background and Purpose— We sought to investigate the impact of hyperglycemia before reperfusion on long-term outcome in patients treated with intravenous tissue plasminogen activator (tPA). Methods— Of 268 consecutive patients with a nonlacunar middle cerebral artery (MCA) stroke evaluated at <3 hours after onset, 73 (27.2%) received intravenous tPA. Serum glucose was determined at baseline before tPA administration. Hyperglycemia was defined as a glucose level >140 mg/dL. National Institutes of Health Stroke Scale (NIHSS) scores were obtained at baseline and 24 hours. Transcranial Doppler monitoring of recanalization and reocclusion was conducted during the first 24 hours. Total infarct volume was measured on CT at day 5 to 7. Modified Rankin Scale was used to assess outcome at 3 months. Results— Median NIHSS score was 17. At baseline, 31 patients (42.5%) were hyperglycemic and 42 (57.5%) normoglycemic. Early reperfusion (<6 hours) occurred in 43 patients (58.9%). Admission blood glucose correlated negatively with the degree of neurological improvement at 24 hours in reperfused (r =−0.43;P =0.019) but not in nonreperfused (r =−0.20;P =0.21) tPA-treated patients. Increased age (P =0.014), history of diabetes mellitus (P =0.043), admission glucose >140 mg/dL (P =0.002), and early reocclusion (P =0.004) were factors associated with poor outcome among reperfused patients. A logistic regression modeling revealed that only admission glucose value >140 mg/dL (odds ratio, 8.4; 95% CI, 1.76 to 40.02;P =0.005) emerged as an independent predictor of poor outcome despite tPA-induced recanalization. In patients with 6-hour persistent MCA occlusion, baseline NIHSS score >15 points (P =0.011) and proximal MCA occlusion (P =0.039) were variables associated with poor outcome on univariate analysis. In a logistic regression model, only NIHSS score >15 points (odds ratio, 11.9; 95% CI, 1.48 to 97.1;P =0.032) remained as an independent predictor of poor outcome and functional dependence at 3 months in nonreperfused tPA-treated patients. Conclusions— Hyperglycemia before reperfusion may in part counterbalance the beneficial effect of early restoration of blood flow, which translates into a worse outcome in hyperglycemic patients despite tPA-induced recanalization.
Computerized detection of breast lesions in multi-centre and multi-instrument DCE-MR data using 3D principal component maps and template matching

In this study, we introduce a novel, robust and accurate computerized algorithm based on volumetric principal component maps and template matching that facilitates lesion detection on dynamic contrast-enhanced MR. The study dataset comprises 24 204 contrast-enhanced breast MR images corresponding to 4034 axial slices from 47 women in the UK multi-centre study of MRI screening for breast cancer and categorized as high risk. The scans analysed here were performed on six different models of scanner from three commercial vendors, sited in 13 clinics around the UK. 1952 slices from this dataset, containing 15 benign and 13 malignant lesions, were used for training. The remaining 2082 slices, with 14 benign and 12 malignant lesions, were used for test purposes. To prevent false positives being detected from other tissues and regions of the body, breast volumes are segmented from pre-contrast images using a fast semi-automated algorithm. Principal component analysis is applied to the centred intensity vectors formed from the dynamic contrast-enhanced T1-weighted images of the segmented breasts, followed by automatic thresholding to eliminate fatty tissues and slowly enhancing normal parenchyma and a convolution and filtering process to minimize artefacts from moderately enhanced normal parenchyma and blood vessels. Finally, suspicious lesions are identified through a volumetric sixfold neighbourhood connectivity search and calculation of two morphological features: volume and volumetric eccentricity, to exclude highly enhanced blood vessels, nipples and normal parenchyma and to localize lesions. This provides satisfactory lesion localization. For a detection sensitivity of 100%, the overall false-positive detection rate of the system is 1.02/lesion, 1.17/case and 0.08/slice, comparing favourably with previous studies. This approach may facilitate detection of lesions in multi-centre and multi-instrument dynamic contrast-enhanced breast MR data.
Laser ablation of Dbx1 neurons in the pre-Bötzinger complex stops inspiratory rhythm and impairs output in neonatal mice

To understand the neural origins of rhythmic behavior one must characterize the central pattern generator circuit and quantify the population size needed to sustain functionality. Breathing-related interneurons of the brainstem pre-Bötzinger complex (preBötC) that putatively comprise the core respiratory rhythm generator in mammals are derived from Dbx1-expressing precursors. Here, we show that selective photonic destruction of Dbx1 preBötC neurons in neonatal mouse slices impairs respiratory rhythm but surprisingly also the magnitude of motor output; respiratory hypoglossal nerve discharge decreased and its frequency steadily diminished until rhythm stopped irreversibly after 85±20 (mean ± SEM) cellular ablations, which corresponds to ∼15% of the estimated population. These results demonstrate that a single canonical interneuron class generates respiratory rhythm and contributes in a premotor capacity, whereas these functions are normally attributed to discrete populations. We also establish quantitative cellular parameters that govern network viability, which may have ramifications for respiratory pathology in disease states. DOI: http://dx.doi. org/10.7554/eLife.03427. 001
Clad radiation rating in optical polymer fibers

Classical polymer optical fibers are made with chemicals. The core has the large diameter, and the clad is a thin layer of modified polymer. The clad radiation can propagate quite well in specialist polymer fibers as double clad. It can also be generated in specific situation in classical polymer fibers. This work presents the idea of clad radiation rating in classical polymer fibers. Clad radiation phenomenon functional model has been proposed. The experiment data has been used for specification of it parameter's values. The experiment examples, which demonstrate model correctness, are shown.