Miracle-dz/UniFAR-FTUs huggingface dataset:
Insights on Social Recommender Systems

Recommender Systems (RS) algorithms are growing more and more complex to follow requirements from real-world applications. Nevertheless, the slight improvement they often bring may not compensate the considerable increase in algorithmic complexity and decrease in computational performance. Contrarily, context aspects such as social awareness are still not much explored. In view of that, this paper proposes insights on how to possibly achieve more efficient and accurate predictions for recommendations by exploring multiple dimensions of a RS architecture. A framework is designed, comprised of a Facebook application called MyPopCorn and some scenarios of user neighborhood RSs are proposed. The first one investigates how to recommend movies based on a narrowed subset of collaborative data, extracted from the social connections of the active user. Secondly, connections between users enable a solution for the cold-start problem. Preferences from social connections are aggregated, producing a temporary profile of the new user. Finally, a third dimension is explored regarding evaluation metrics. Results from traditional evaluation by offline cross-validation are compared to measuring prediction accuracy of online feedback data. These insights propose how community-based RS designs might take advantage of social context features. Results show that all three proposed solutions perform better assuming some conditions. Social neighborhoods can often provide representative data for collaborative filtering user-neighborhood techniques, improving a lot the RS performance in terms of computational complexity metric without compromising prediction accuracy. Assuming a user has a dense social network, the cold-start problem can be easily tackled. Finally, rating prediction accuracy performs better when evaluated online than by offline cross-validation.
REINFORCEMENT LEARNING IN COMPLEX REAL WORLD DOMAINS: A REVIEW

Reinforcement Learning is an area of Machine Learning inspired by behaviorist psychology based on the mechanism of learning from rewards. RL does not require prior knowledge and automatically get optimal policy with the help of knowledge obtained by trial-and-error and continuous interaction with the dynamic environment. In complex real world domains implementing RL algorithms is the major practical problem due to the large and continuous space. It can give rise to problems like Curse of Dimensionality, Partial Observability Problem, Credit Structuring Problem, Generalization and Exploration-Exploitation Dilemma. This paper gives an introduction to Reinforcement Learning, discusses its basic model and system structure, and discusses the problems faced while implementing RL algorithms in complex real world domains. At last but not the least this paper briefly describes the techniques which can make the working of RL process easier in the complex domains. It concludes with research scope of RL in complex real world.
ECE 5325/6325: Wireless Communication Systems Lecture Notes, Spring 2013

Multiple-input multiple output (MIMO) is a particular type of space and/or polarization diversity in which both the transmitter and receiver may use multiple antennas. Figure 1: Transmit and receive space diversity schemes: (a) traditional space diversity with receiver combining, called single input multiple output (SIMO); (b) transmit diversity, which may use Alamouti's scheme, called multiple input single output (MISO); (c) 2×2 multiple input multiple output (MIMO). We're going to introduce MIMO by comparing it to maximal ratio combining (MRC) using a receiver with two antennas (space diversity), as shown in Figure 1(a). Let's assume that the transmitter sends symbol voltage s. Assume the channel from TX to RX antenna 0 experiences total channel power gain α 2 0 (or voltage gain α 0), and the channel from TX to RX antenna 1 experiences total channel power gain α 2 1 (or voltage gain α 1). We said that in MRC, the received signals r 0 and r 1 are multiplied by the square root of the SNRs. Multiplying received signals by a constant doesn't help (it amplifies the noise as much as the signal) so it really matters to
Lifting schemes for joint coding of stereoscopic pairs of satellite images)

Stereo data compression is an important issue for the new generation of vision systems. In this paper, we are interested in lossless coding methods for stereo images allowing progressive reconstruction. Most of the existing approaches account for the mutual similarities between the left and the right images. More precisely, the disparity compensation process consists in predicting the right image from the left one based on the disparity map. Then, the disparity map, the reference image, and the residual image are encoded. In this work, we propose a novel approach based on the concept of vector lifting scheme. Its main feature is that it does not generate one residual image but two compact multiresolution representations of the left and the right views, driven by the underlying disparity map. Experimental results show a significant improvement using this technique compared with conventional methods.
Natural course of a community sample of women with binge eating disorder.

OBJECTIVE A community sample of women with binge eating disorder (BED) was followed for a period of 6 months, in order to examine the natural course of the disorder. METHOD Baseline, 3-, and 6-month assessments were conducted. The following variables were examined: eating disorder symptomatology, importance of weight or shape, psychopathology, social adjustment, childhood sexual abuse, childhood obesity, parental obesity, and parental psychopathology. RESULTS After the 3-month follow-up, 10 of the original sample of 31 participants dropped out of the study; drop-outs were more likely to have reported a history of sexual abuse. Of the 21 remaining participants, 11 continued to suffer from full-syndrome BED at 6-month follow-up, while the remaining 10 appeared to be in partial remission. There were no significant baseline predictors of outcome. CONCLUSION It appears that for some women with BED, the eating disorder improves with a decrease in binge eating and importance of weight or shape. For others, the eating disorder symptoms remain constant.
Lower body realization of the baby humanoid - ‘iCub’

Nowadays, the understanding of the human cognition and it application to robotic systems forms a great challenge of research. The iCub is a robotic platform that was developed within the RobotCub European project to provide the cognition research community with an open baby- humanoid platform for understanding and development of cognitive systems. In this paper we present the design requirements and mechanical realization of the lower body developed for the "iCub". In particular the leg and the waist mechanisms adopted for lower body to match the size and physical abilities of a 2 frac12 year old human baby are introduced.
Acute effects of wheel running on adult hippocampal precursor cells in mice are not caused by changes in cell cycle length or S phase length

Exercise stimulates cellular brain plasticity by extending the pool of proliferating neural precursor cells in the adult hippocampus. This effect has been investigated extensively, but the most immediate cellular effect induced by exercise that results in this acute increase in the number of cycling cells remained unclear. In the developing brain as well as adult pathological models, cell cycle alterations have a major influence on the balance between proliferative and neurogenic divisions. In this study we investigated whether this might also apply to the acute physiological pro-neurogenic stimulus of physical exercise in adulthood. Do changes in cell cycle precede the measurable increase in proliferation? After 5 days of voluntary wheel running, however, we measured only a very small, statistically not significant acceleration in cell cycle, which could not quantitatively explain the observed increase in proliferating cells after exercise. Thus, at this acute stage, changes at the level of cell cycle control is not the primary causal mechanism for the expansion of the precursor cell population, although with time after the stimulus changes in cell cycle of the entire population of labeled cells might be the result of the expanded pool of cells that have progressed to the advanced neurogenic stages with shorter cell cycle length.
SpeakBySinging: Converting singing voices to speaking voices while retaining voice timbre

This paper describes a singing-to-speaking synthesis system called “SpeakBySinging” that can synthesize a speaking voice from an input singing voice and the song lyrics. The system controls three acoustic features that determine the difference between speaking and singing voices: the fundamental frequency (F0), phoneme duration, and power (volume). By changing these features of a singing voice, the system synthesizes a speaking voice while retaining the timbre of the singing voice. The system first analyzes the singing voice to extract the F0 contour, the duration of each phoneme of the lyrics, and the power. These features are then converted to target values that are obtained by feeding the lyrics into a traditional text-to-speech (TTS) system. The system finally generates a speaking voice that preserves the timbre of the singing voice but has speech-like features. Experimental results show that SpeakBySinging can convert singing voices into speaking voices whose timbre is almost the same as the original singing voices.
Systemic antibody responses to gut commensal bacteria during chronic HIV-1 infection

Background Human systemic antibody responses to commensal microbiota are not well characterised during health and disease. Of particular interest is the analysis of their potential modulation caused by chronic HIV-1 infection which is associated with sustained enteropathy and systemic B cell disturbances reflected by impaired B cell responses and chronic B cell hyperactivity. The mechanisms underlying B cell hyperactivation and the specificities of the resulting hypergammaglobulinaemia are only poorly understood. Methods By a technique referred to as live bacterial FACS (fluorescence-activated cell sorting), the present study investigated systemic antibody responses to several gut and skin commensal bacteria as well as Candida albicans in longitudinal plasma and serum samples from healthy donors, chronic HIV-1-infected individuals with or without diarrhoea and patients with inflammatory bowel disease (IBD). Results The data show that systemic antibody responses to the commensal microbiota were abundantly present in humans and remained remarkably stable over years. Overall systemic antibody responses to gut commensal bacteria were not affected during chronic HIV-1 infection, with titres decreasing when normalised to elevated plasma immunoglobulin G (IgG) levels found in patients with HIV. In contrast, increases in the titres of high affinity antimicrobiota antibodies were detected in patients with IBD, demonstrating that conditions with known increased intestinal permeability and aberrant mutualism can induce changes in antibody titres observed in these assays. Conclusion Neither HIV-associated enteropathy nor B cell dysfunction impact on the high-affinity systemic antibody responses to gut commensal bacteria. HIV-associated hypergammaglobulinaemia is therefore unlikely to be driven by induction of antimicrobiota antibodies.
Healthy individuals' perspectives on clinical research protocols and influences on enrollment decisions

ABSTRACT Background: Understanding the perspectives of healthy individuals is important ethically and for the advancement of science. We assessed perceptions of risk associated with research procedures, comparing views of healthy individuals with and without experience in clinical research, and the respondents' reported willingness to volunteer. Methods: Semistructured interviews and written surveys were conducted. Study participants were healthy individuals, half of whom were currently enrolled in clinical research and half of whom had no prior experience in clinical research. Participants were queried regarding seven “minimal risk” or “greater than minimal risk” protocol vignettes with procedures of three types: routine diagnostic tests, more burdensome (i.e., more effort or potential harm) diagnostic tests, and pharmacologic interventions. Views of influences on enrollment decisions were also assessed. Results: Most healthy individuals indicated that protocols with more burdensome or pharmacologic interventions were very risky (59%, 58%), as opposed to routine diagnostic test procedures (32%). Respondents' willingness to enroll in protocols varied by type of protocol (p value < .001) and was inversely correlated with risk assessments (regression coefficients from GEE = −0.4; −0.5; −0.7). The odds of healthy individuals with research experience expressing strong willingness to enroll in the depicted protocols were twice the odds of healthy individuals without research experience expressing the same level of willingness (OR = 2.0 95% CI: [1.1, 3.9]). Respondents did not assign risk categories as institutional review boards (IRBs) would, as indicated by low agreement (26%) between respondent and expert opinion on minimal risk protocols. Conclusions: Perceptions of procedure risk appear to influence healthy individuals' willingness to enroll in protocols. Participants with experience in clinical research were far more likely to express willingness to enroll, a finding with important scientific and ethical implications. The lack of alignment between healthy individuals' views of protocol risk and IRB categorization warrants further study.
The X-ray properties of the energetic pulsar PSR J1838−0655

We present and interpret several new X-ray features of the X-ray pulsar PSR J1838―0655. The X-ray data are obtained from the archival data of Chandra, RXTE and Suzaku. We combine all these X-ray data and fit the spectra with different models. We find that the joint spectra are difficult to fit with a single power law; a broken power-law model with a break at around 6.5 keV can improve the fit significantly. The photon index changes from Γ = 1.0 (below 6.5 keV) to 1.5 (above 6.5 keV); this indicates a softer spectral behaviour at hard X-rays. The X-ray flux at 2-20 keV is found to be 1.6 x 10 ―11 erg cm ―2 s ―1 . The conversion efficiency from the spin-down luminosity is ∼0.9 per cent at 0.8-10 keV, which is much higher than that (∼10 ―3 to 10 ―4 per cent) of the pulsars that show similar timing properties. We discuss non-thermal radiation mechanisms for the observed high X-ray conversion efficiency and find that emission from the magnetosphere of a greatly inclined rotator is the most favourable interpretation for the conversion rate and the pulse profiles at X-ray bands. A line feature close to 6.65 keV is also detected in the spectra of Suzaku/X-ray imaging spectrometer; it might be the Kα emission of highly ionized Fe surrounding the pulsar.
Plane-based Calibration of a Camera with Varying Focal Length: the Centre Line Constraint

This paper deals with the problem of calibrating a (moving) camera with varying focal length, from views of a planar pattern with a known Euclidean structure. The main issue under discussion is to find a new method whose complexity does not dramatically increase with the number of views, contrary to existing methods. Our contribution is to relate this calibration problem to the Centre Line (CL) constraint, that is the principal point locus when planar figures are in perpective correspondence, in accordance with Poncelet’s theorem. We demonstrate that the CL equation is irrespective of the focal length and holds for each view, with only three unknown parameters whose values are constant in the images. We define its analytic equation with coefficients computed from the world-plane to image homography matrices. An important aspect is that we can make use of it as a linear cost function that expresses a geometric error (instead of algebraic errors in existing methods). We explain why an “optimal” solution can be obtained when pixels are rectangular. The simulations on synthetic data and an application with real images confirm the two strong points of our method with respect to existing ones: a lower computation cost and a better system conditioning that permits to obtain more accurate results.
Association between Q192R paraoxonase 1 polymorphism and serumadipocyte-fatty acid binding protein (FABP4) levels in Mexican women

Abstract Aim: This study aimed to evaluate the genetic effects of PON1 Q192R polymorphism on serum FABP4 levels in Mexican women. Methods: PON1 Q192R polymorphism was genotyped using a TaqMan allelic discrimination assay and serum FABP4 concentration was measured using an enzyme-linked immunosorbent assay. Results: The distribution of genotype frequencies in the assessed women (PON1 Q192R polymorphism) was QQ = 20%, QR = 48% and RR = 32%. Significantly higher serum FABP4 levels were found in women with genotype QR/RR (20.6 ± 2.20 ng/mL), when compared with the levels found in the QQ group (12.8 ± 1.70 ng/mL) (p = .004). After, the odds ratio (OR) was calculated by binomial logistic regression analysis and a significantly higher OR was found in the QR/RR group when compared with the QQ group (OR = 3.45; 95% CI = 1.80–16.50; p < .05). Conclusion: The results support an association between 192R-allele of the PON1 polymorphism (Q192R) and increased serum FABP4 levels (suggested as an early biomarker of CVDs risk) in assessed Mexican women.
Single Image Super-Resolution via Locally Regularized Anchored Neighborhood Regression and Nonlocal Means

The goal of learning-based image super resolution (SR) is to generate a plausible and visually pleasing high-resolution (HR) image from a given low-resolution (LR) input. The SR problem is severely underconstrained, and it has to rely on examples or some strong image priors to reconstruct the missing HR image details. This paper addresses the problem of learning the mapping functions (i.e., projection matrices) between the LR and HR images based on a dictionary of LR and HR examples. Encouraged by recent developments in image prior modeling, where the state-of-the-art algorithms are formed with nonlocal self-similarity and local geometry priors, we seek an SR algorithm of similar nature that will incorporate these two priors into the learning from LR space to HR space. The nonlocal self-similarity prior takes advantage of the redundancy of similar patches in natural images, while the local geometry prior of the data space can be used to regularize the modeling of the nonlinear relationship between LR and HR spaces. Based on the above two considerations, we first apply the local geometry prior to regularize the patch representation, and then utilize the nonlocal means filter to improve the super-resolved outcome. Experimental results verify the effectiveness of the proposed algorithm compared with the state-of-the-art SR methods.
Mobility Resistant Clustering in Multi-Hop Wireless Networks

This paper presents a Distributed Efficient Clustering Approach (DECA) for mobility-resistant and energy-efficient clustering in multi-hop wireless networks. The clusterheads cover the whole network and each node in the network can exclusively determine the single cluster it belongs. DECA is fully distributed, each node transmits only one message during clustering operation, and the algorithm terminates in deterministic time without iterations. Theoretical results show the correctness of DECA, and extensive simulation results demonstrate that DECA is energy-efficient and robust against node mobility.
A Novel Direct Aerodynamically Assisted Threading Methodology for Generating Biologically Viable Microthreads Encapsulating Living Primary Cells

In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio-polymeric microthread from which active biological scaffolds were fabricated (Townsend-Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post-processed cells as composite threads and scaffolds are being investigated in-depth at a cellular level to establish if the processing methodology has any affect on the cellular make-up. We now demonstrate a competing non-electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio-threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post-processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Reem-B: An autonomous lightweight human-size humanoid robot

This paper introduces the humanoid robot Reem-B, built by Pal robotics as a research platform in the field of service robots. The idea is to produce robots that can help humans and cohabit their environments. For this purpose, the body plan, sensory and actuator system of the robot, as well as its cognitive abilities must be designed to perform real-world tasks including dynamic walking, interaction with people or object recognition and manipulation. Reem-B achieves this scope by using two legs, two strong arms with fingered hands, and a software suite that controls all its degrees of freedom, coordinating them with vision and auditory systems. The main difference with other humanoids of its size is its level of autonomy. Autonomy in this robot has been improved from other robots at three different levels: with an increased battery life (estimated twice of the competitors), with the ability to autonomously navigate in indoor environments while avoiding obstacles, and by integrating all the control systems within the robot itself.