Miracle-dz/UniFAR-FTUs huggingface dataset:
Analysis of Scale Effects in Peer-to-Peer Networks

In this paper, we study both positive and negative scale effects on the operations of peer-to-peer (P2P) file sharing networks and propose the optimal sizing (number of peers) and grouping (number of directory intermediary) decisions. Using analytical models and simulation, we evaluate various performance metrics to investigate the characteristics of a P2P network. Our results show that increasing network scale has a positive effect on the expected content availability and transmission cost, but a negative effect on the expected provision and search costs. We propose an explicit expression for the overall utility of a content sharing P2P community that incorporates tradeoffs among all of the performance measures. This utility function is maximized numerically to obtain the optimal network size (or scale). We also investigate the impact of various P2P network parameters on the performance measures as well as optimal scaling decisions. Furthermore, we extend the model to examine the grouping decision in networks with symmetric interconnection structures and compare the performance between random- and location-based grouping policies.
D-Q models for resonant converters

A systematic modeling method for resonant converters is proposed. This method develops low frequency D-Q models for resonant converters. For a given resonant tank, its orthogonal counterpart is constructed. By combining these two orthogonal tanks, a complex circuit is obtained. The complex circuit is then expressed into a D-Q form circuit. Every variable in the D-Q circuit can be treated as a rotating vector with its envelope modulated by a low frequency function. By removing high frequency terms, the low frequency D-Q model of the resonant converter is derived. This D-Q model has a DC operating point and can predict large signal transitions of the resonant converter with little computation. By perturbing the D-Q model around its DC operating point, equivalent circuits for the small signal models are derived. As an example, the series-parallel resonant DC/DC converter is analyzed by the proposed method. Startup process by the D-Q model agrees with the PSPICE simulation results very well. From the equivalent circuits of the small signal model, transfer functions of input-to-output, control-to-output are obtained as well as the output impedance. They are all verified by SIMPLIS simulation. This modeling technique is applicable to any resonant converter and need little computation.
Classification of Packet Transmission Outcomes in Wireless Sensor Networks

In wireless networks, it is important to determine the outcome of packet transmissions for networking protocols. In this paper, we design a transmission outcome classifier for IEEE 802.15. 4 wireless networks based on received signal strength indicator and link quality indicator values. Our classifier performs loss differentiation by analyzing statistical differences between weak signal and collision losses. We implement our proposed classifier using the CC2500 RF transceiver and evaluate it experimentally. The results show that our classifier can accurately detect packet transmissions as well as distinguish wireless losses due to weak signals and multiple access collisions, with a maximum error rate of 15%. We apply the classifier to probabilistic polling, which is a MAC protocol designed for energy harvesting wireless sensor networks, and show experimentally that it is able to achieve close to or even exceed the theoretical throughput due to packet capture effect.
Reducing structural bias in technology mapping

Technology mapping based on DAG-covering suffers from the problem of structural bias: the structure of the mapped netlist depends strongly on the subject graph. In this paper we present a new mapper aimed at mitigating structural bias. It is based on a simplified cut-based Boolean matching algorithm, and using the speed afforded by this simplification we explore two ideas to reduce structural bias. The first, called lossless synthesis, leverages recent advances in structure-based combinational equivalence checking to combine the different networks seen during technology independent synthesis into a single network with choices in a scalable manner. We show how cut based mapping extends naturally to handle such networks with choices. The second idea is to combine several library gates into a single gate (called a supergate) in order to make the matching process less local. We show how supergates help address the structural bias problem, and how they fit naturally into the cut-based Boolean matching scheme. An implementation based on these ideas significantly outperforms state-of-the-art mappers in terms of delay, area and run-time on academic and industrial benchmarks.
Radiation efficiency of printed slot antennas backed by a ground reflector

Although in the literature the back-reflector technique has been extensively used as a means of rendering the slot patterns unidirectional, there is no quantitative information on the effectiveness of this approach. In this work, the use of a back reflector as a means of increasing the efficiency and antenna gain of printed slot antennas is evaluated. For this purpose, the radiation efficiency of reflector-backed printed slot antennas on either electrically thin or thick substrates is thoroughly characterized; both single and twin slot elements are considered. Twin slot elements have been previously proposed for the reduction of the coupling to the dominant surface-wave mode in the case of electrically thick substrates. In this article, twin slot elements are explored as a means of enhancing the radiation efficiency of printed slots backed by a ground reflector. It is shown that in the case of thick substrates, simultaneous partial cancellation of the surface-wave and the parallel-plate TEM modes can be achieved. On the other hand, in the case of thin substrates where the back radiation is severe, the twin slot element can be utilized for the drastic reduction of the parallel-plate TEM mode.
A PTAS for Computing the Supremum of Gaussian Processes

We give a polynomial time approximation scheme (PTAS) for computing the supremum of a Gaussian process. That is, given a finite set of vectors V ⊆ Rd, we compute a (1+ε)-factor approximation to EX←Nd[supv∈V |〈v, X〉|] deterministically in time poly(d) · |V|(Oε)(1). Previously, only a constant factor deterministic polynomial time approximation algorithm was known due to the work of Ding, Lee and Peres [1]. This answers an open question of Lee [2] and Ding [3]. The study of supremum of Gaussian processes is of considerable importance in probability with applications in functional analysis, convex geometry, and in light of the recent breakthrough work of Ding, Lee and Peres [1], to random walks on finite graphs. As such our result could be of use elsewhere. In particular, combining with the recent work of Ding [3], our result yields a PTAS for computing the cover time of bounded degree graphs. Previously, such algorithms were known only for trees. Along the way, we also give an explicit oblivious estimator for semi-norms in Gaussian space with optimal query complexity. Our algorithm and its analysis are elementary in nature using two classical comparison inequalities in convex geometry- Slepian's lemma and Kanter's lemma.
A review on energy harvesting approaches for renewable energies from ambient vibrations and acoustic waves using piezoelectricity

The principal objective of this article is to categorically review and compare the state of the art vibration based energy harvesting approaches. To evaluate the contemporary methodologies with respect to their physics, average power output and operational frequencies, systematically divided and easy readable tables are presented followed by the description of the energy harvesting methods. Energy harvesting is the process of obtaining electrical energy from the surrounding vibratory mechanical systems through an energy conversion method using smart structures, like, piezoelectric, electrostatic materials. Recent advancements in low power electronic gadgets, micro electro mechanical systems, and wireless sensors have significantly increased local power demand. In order to circumvent the energy demand; to allow limitless power supply, and to avoid chemical waste from conventional batteries, low power local energy harvesters are proposed for harvesting energy from different ambient energy sources. Piezoelectric materials have received tremendous interest in energy harvesting technology due to its unique ability to capitalize the ambient vibrations to generate electric potential. Their crystalline configuration allows the material to convert mechanical strain energy into electrical potential, and vice versa. This article discusses the various approaches in vibration based energy scavenging where piezoelectric materials are employed as the energy conversion medium.
Value of small intestinal bile acid analysis in the diagnosis of the stagnant loop syndrome

We have studied simple methods of analysing bile acids in human small intestinal aspirates, in order to assess their suitability for the routine clinical investigation of patients with steatorrhoea. Following extraction into methanol, samples were analysed qualitatively for bile acid deconjugation by thin-layer chromatography and quantitatively by the 3-alpha-hydroxysteroid dehydrogenase enzyme assay. These methods were found to give good recoveries, and to be sensitive, accurate, and specific, in addition to being sufficiently simple and rapid for routine diagnostic purposes. This diagnostic procedure was applied to the identification of patients with steatorrhoea due to the stagnant loop syndrome, and was compared with other tests for this condition, viz, study of the small intestinal bacterial flora, urinary indican excretion, and the Schilling test with added intrinsic factor. Three groups of subjects were studied; group I consisted of nine patients with steatorrhoea due to the stagnant loop syndrome; group II (disease control group) of six patients with an anatomical stagnant loop that was not causing steatorrhoea; and group III (normal control group) of 11 subjects with no known gastrointestinal disease. The screening of postprandial upper jejunal samples for bile acid deconjugation proved the most useful diagnostic test, being positive in eight out of nine patients from group I, but in none of those from groups II and III. At lower levels of the small intestine, bile acid deconjugation was found in subjects from groups II and III. The other three diagnostic tests discriminated poorly between subjects from group I and those from group II.
Hostility and Platelet Reactivity in Individuals Without a History of Cardiovascular Disease Events

Objective: To examine the association between hostility and platelet reactivity in individuals without a prior history of cardiovascular disease (CVD) events. Hostility is associated with incident CVD events, independent of traditional risk factors. Increased platelet reactivity and thrombus formation over a disrupted coronary plaque are fundamental for CVD event onset. Methods: Hypertensive patients (n = 42) without concomitant CVD event history completed the 50-item Cook-Medley Hostility Scale, and a subset score of 27 items (Barefoot Ho) was derived. We examined the relationship between Barefoot Ho scores and platelet aggregation. We also examined individual components of Barefoot Ho (aggressive responding, cynicism, and hostile affect) and their associations with platelet aggregation. Platelet reactivity, induced by adenosine diphosphate (ADP), was assessed by standard light transmission aggregometry, the current gold standard method of platelet aggregation assessment. Results: Barefoot Ho scores were related significantly to increased rate of platelet aggregation in response to ADP. Of the three Barefoot Ho components, only aggressive responding was associated independently with increased platelet aggregation rate. The strength of these relationships did not diminish after adjusting for several standard CVD risk factors. Conclusions: These data demonstrate that hostility, particularly the aggressive responding subtype, is associated with platelet reactivity—a key pathophysiological pathway in the onset of CVD events. ADP = adenosine diphosphate; Barefoot Ho = 27-item Barefoot Hostility Scale; BTG = B-thromboglobulin; CHD = coronary heart disease; CVD = cardiovascular disease; LTA = light transmission aggregometry; PPP = platelet-poor plasma; SI = Structured Interview.
Restoration of CMV-Specific-CD4 T Cells with ART Occurs Early and Is Greater in Those with More Advanced Immunodeficiency

Objectives Restoration of Cytomegalovirus-specific-CD4 T cell (CMV-Sp-CD4) responses partly accounts for the reduction of CMV-disease with antiretroviral-therapy (ART), but CMV-Sp-CD4 may also drive immune activation and immunosenescence. This study characterized the dynamics of CMV-Sp-CD4 after ART initiation and explored associations with CD4 T cell recovery as well as frequency of naïve CD4 T cells at week 96. Methods Fifty HIV-infected, ART-naïve Thai adults with CD4 T cell count ≤350cells/µL and starting ART were evaluated over 96 weeks (ClinicalTrials.gov identifier NCT01296373). CMV-Sp-CD4 was detected by co-expression of CD25/CD134 by flow cytometry after CMV-antigen stimulation. Results All subjects were CMV sero-positive, 4 had quantifiable CMV-DNA (range 2.3-3.9 log10 copies/mL) at baseline but none had clinically apparent CMV-disease. Baseline CMV-Sp-CD4 response was positive in 40 subjects. Those with CD4 T cell count <100cells/µL were less likely to have positive baseline CMV-Sp-CD4 response (P=0.003). Positive baseline CMV-Sp-CD4 response was associated with reduced odds of quantifiable CMV-DNA (P=0.022). Mean CD4 T cell increase at week 96 was 213 cells/µL. This was associated positively with baseline HIV-VL (P=0.001) and negatively with age (P=0.003). The frequency of CMV-Sp-CD4 increased at week 4 (P=0.008), then declined. Those with lower baseline CMV-Sp-CD4 (P=0.009) or CDC category C (P<0.001) had greater increases in CMV-Sp-CD4 at week 4. At week 96, CD4 T cell count was positively (P<0.001) and the frequency of CMV-Sp-CD4 was negatively (P=0.001) associated with the percentage of naïve CD4 T cells. Conclusions Increases in CMV-Sp-CD4 with ART occurred early and were greater in those with more advanced immunodeficiency. The frequency of CMV-Sp-CD4 was associated with reduced naïve CD4 T cells, a marker associated with immunosenescence.
The Oral Microbiome of Denture Wearers Is Influenced by Levels of Natural Dentition

Objectives The composition of dental plaque has been well defined, whereas currently there is limited understanding of the composition of denture plaque and how it directly influences denture related stomatitis (DS). The aims of this study were to compare the microbiomes of denture wearers, and to understand the implications of these towards inter-kingdom and host-pathogen interactions within the oral cavity. Methods Swab samples were obtained from 123 participants wearing either a complete or partial denture; the bacterial composition of each sample was determined using bar-coded illumina MiSeq sequencing of the bacterial hypervariable V4 region of 16S rDNA. Sequencing data processing was undertaken using QIIME, clustered in Operational Taxonomic Units (OTUs) and assigned to taxonomy. The dentures were sonicated to remove the microbial flora residing on the prosthesis, sonicate was then cultured using diagnostic colorex Candida media. Samples of unstimulated saliva were obtained and antimicrobial peptides (AMP) levels were measured by ELISA. Results We have shown that dental and denture plaques are significantly distinct both in composition and diversity and that the oral microbiome composition of a denture wearer is variable and is influenced by the location within the mouth. Dentures and mucosa were predominantly made up of Bacilli and Actinobacteria. Moreover, the presence of natural teeth has a significant impact on the overall microbial composition, when compared to the fully edentulous. Furthermore, increasing levels of Candida spp. positively correlate with Lactobacillus spp. AMPs were quantified, though showed no specific correlations. Conclusions This is the first study to provide a detailed understanding of the oral microbiome of denture wearers and has provided evidence that DS development is more complex than simply a candidal infection. Both fungal and bacterial kingdoms clearly play a role in defining the progression of DS, though we were unable to show a defined role for AMPs.
A reference model for dynamic web service composition systems

Web services have become an emerging and promising technology to design and build complex business applications out of atomic web-based software components. To enforce extensive software reuse and dynamic adaptation, dynamic service composition has experienced an increasing interest in research efforts. Together, the lack of a general conceptual reference model for dynamic web service composition systems and the widespread use of these systems in service-enabled applications constitute a problem of management for these systems. To capture the requirements and challenges of these composition systems, a survey of a representative set of these systems is presented. In this paper, we develop a reference model for describing the functional structure and evaluating the performance of dynamic web service composition systems based on existing dynamic web service composition platforms and prototypes. To the best of our knowledge there has been no such model in the literature.
Enhancement of the porous silicon layer photoluminescence with a thin cerium sulfate films

The photoluminescence (PL) of the porous silicon (PS) can be enhanced by coating it with a thin cerium sulfate (Ce (SO4)2) films. The cerium sulfate (Ce (SO4)2) films were deposited by using electrochemical technique on porous silicon (PS) prepared by electrochemical anodization of P-type (100) Si. The surface bond configuration of PS was monitored by Fourier transmission infrared spectroscopy (FTIR) and it was found that the PS surface was oxidized after metallization. The presence of cerium and sulfur in PS is shown from scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). The photoluminescence (PL) measurements on PS and (Ce (SO4)2) coated PS shows that it is desirable to deposit (Ce (SO4)2) for 30 min.
Effects of a high-protein, low-carbohydrate v. high-protein, moderate-carbohydrate weight-loss diet on antioxidant status, endothelial markers and plasma indices of the cardiometabolic profile

There are concerns that weight-loss (WL) diets based on very low carbohydrate (LC) intake have a negative impact on antioxidant status and biomarkers of cardiovascular and metabolic health. Obese men (n 16) participated in a randomised, cross-over design diet trial, with food provided daily, at approximately 8·3 MJ/d (approximately 70 % of energy maintenance requirements). They were provided with two high-protein diets (30 % of energy), each for a 4-week period, involving a LC (4 % carbohydrate) and a moderate carbohydrate (MC, 35 % carbohydrate) content. Body weight was measured daily, and weekly blood samples were collected. On average, subjects lost 6·75 and 4·32 kg of weight on the LC and MC diets, respectively (P < 0·001, sed 0·350). Although the LC and MC diets were associated with a small reduction in plasma concentrations of retinol, vitamin E (α-tocopherol) and β-cryptoxanthin (P < 0·005), these were still above the values indicative of deficiency. Interestingly, plasma vitamin C concentrations increased on consumption of the LC diet (P < 0·05). Plasma markers of insulin resistance (P < 0·001), lipaemia and inflammation (P < 0·05, TNF-α and IL-10) improved similarly on both diets. There was no change in other cardiovascular markers with WL. The present data suggest that a LC WL diet does not impair plasma indices of cardiometabolic health, at least within 4 weeks, in otherwise healthy obese subjects. In general, improvements in metabolic health associated with WL were similar between the LC and MC diets. Antioxidant supplements may be warranted if LC WL diets are consumed for a prolonged period.
A perceptually grounded model of the singular–plural distinction

abstract Embodied theories of language posit that the human brain’s adaptations for language exploit pre-existing perceptual and motor mechanisms for interacting with the world. In this paper we propose an embodied account of the linguistic distinction between singular and plural, encoded in the system of grammatical number in many of the world’s languages. We introduce a neural network model of visual object classification and spatial attention, informed by a collection of findings in psychology and neuroscience. The classification component of the model computes the type associated with a visual stimulus without identifying the number of objects present. The distinction between singular and plural is made by a separate mechanism in the attentional system, which directs the classifier towards the local or global features of the stimulus. The classifier can directly deliver the semantics of uninflected concrete noun stems, while the attentional mechanism can directly deliver the semantics of singular and plural number features.