Miracle-dz/UniFAR-FTUs huggingface dataset:
Signal classification based on spectral redundancy and neural network ensembles

In the last couple of decades, the introduction of new wireless applications and services, which have to coexist with already deployed ones, is creating problems in the allocation of the unlicensed spectrum. In order to overcome such a problem, by exploiting efficiently the spectral resources, dynamic spectrum access has been proposed. In this context, cognitive radio represents one of the most promising technologies which allows an efficient use of the radio resource by collecting, processing and exploiting information regarding the spectrum utilization in a monitored area. To this end, in this paper the problem of classifying similar signals characterized by different spectral redundancies is addressed by using a neural network ensemble. A set of simulations have been carried out to prove the effectiveness of the considered algorithms and numerical results are reported.
Low-complexity iterative decoding for coded differential transmission

In this paper, a power-efficient low-complexity iterative receiver structure for noncoherent transmission over Rayleigh flat fading channels without channel state information (CSI) is presented. As the main contribution, several novel decision-feedback assisted differential demodulators are derived, which are well-suited implementation. Thereby, the general case of multiple transmit and multiple receive antennas is considered. We further provide analytical expressions for the achievable bit-error rate, which in good accordance with simulation results highlight the advantageous properties of the proposed receiver structure. Despite its simple components, the noncoherent iterative receiver without CSI can outperform a coherent scheme assuming perfect CSI.
Acinetobacter baumannii Secretes Cytotoxic Outer Membrane Protein A via Outer Membrane Vesicles

Acinetobacter baumannii is an important nosocomial pathogen that causes a high morbidity and mortality rate in infected patients, but pathogenic mechanisms of this microorganism regarding the secretion and delivery of virulence factors to host cells have not been characterized. Gram-negative bacteria naturally secrete outer membrane vesicles (OMVs) that play a role in the delivery of virulence factors to host cells. A. baumannii has been shown to secrete OMVs when cultured in vitro, but the role of OMVs in A. baumannii pathogenesis is not well elucidated. In the present study, we evaluated the secretion and delivery of virulence factors of A. baumannii to host cells via the OMVs and assessed the cytotoxic activity of outer membrane protein A (AbOmpA) packaged in the OMVs. A. baumannii ATCC 19606T secreted OMVs during in vivo infection as well as in vitro cultures. Potential virulence factors, including AbOmpA and tissue-degrading enzymes, were associated with A. baumannii OMVs. A. baumannii OMVs interacted with lipid rafts in the plasma membranes and then delivered virulence factors to host cells. The OMVs from A. baumannii ATCC 19606T induced apoptosis of host cells, whereas this effect was not detected in the OMVs from the ΔompA mutant, thereby reflecting AbOmpA-dependent host cell death. The N-terminal region of AbOmpA22-170 was responsible for host cell death. In conclusion, the OMV-mediated delivery of virulence factors to host cells may well contribute to pathogenesis during A. baumannii infection.
Predicting Personalized Image Emotion Perceptions in Social Networks

Images can convey rich semantics and induce various emotions to viewers. Most existing works on affective image analysis focused on predicting the dominant emotions for the majority of viewers. However, such dominant emotion is often insufficient in real-world applications, as the emotions that are induced by an image are highly subjective and different with respect to different viewers. In this paper, we propose to predict the personalized emotion perceptions of images for each individual viewer. Different types of factors that may affect personalized image emotion perceptions, including visual content, social context, temporal evolution, and location influence, are jointly investigated. Rolling multi-task hypergraph learning (RMTHG) is presented to consistently combine these factors and a learning algorithm is designed for automatic optimization. For evaluation, we set up a large scale image emotion dataset from Flickr, named Image-Emotion-Social-Net, on both dimensional and categorical emotion representations with over 1 million images and about 8,000 users. Experiments conducted on this dataset demonstrate that the proposed method can achieve significant performance gains on personalized emotion classification, as compared to several state-of-the-art approaches.
Origin and Evolution of the Unique Hepatitis C Virus Circulating Recombinant Form 2k/1b

ABSTRACT Since its initial identification in St. Petersburg, Russia, the recombinant hepatitis C virus (HCV) 2k/1b has been isolated from several countries throughout Eurasia. The 2k/1b strain is the only recombinant HCV to have spread widely, raising questions about the epidemiological background in which it first appeared. In order to further understand the circumstances by which HCV recombinants might be formed and spread, we estimated the date of the recombination event that generated the 2k/1b strain using a Bayesian phylogenetic approach. Our study incorporates newly isolated 2k/1b strains from Amsterdam, The Netherlands, and has employed a hierarchical Bayesian framework to combine information from different genomic regions. We estimate that 2k/1b originated sometime between 1923 and 1956, substantially before the first detection of the strain in 1999. The timescale and the geographic spread of 2k/1b suggest that it originated in the former Soviet Union at about the time that the world's first centralized national blood transfusion and storage service was being established. We also reconstructed the epidemic history of 2k/1b using coalescent theory-based methods, matching patterns previously reported for other epidemic HCV subtypes. This study demonstrates the practicality of jointly estimating dates of recombination from flanking regions of the breakpoint and further illustrates that rare genetic-exchange events can be particularly informative about the underlying epidemiological processes.
On the Statistical Learning Ability of Evolution Strategies

We explore the ability of Evolution Strategies (ESs) to statistically learn the local landscape. Specifically, we consider ESs operating only with isotropic Gaussian mutations near the optimum and investigate the covariance matrix when constructed out of selected individuals by truncation. Unlike previous studies, we do not assume a Derandomization adaptation scheme, nor do we use Information Geometric Optimization in our proofs. We prove that the statistically constructed covariance matrix over such selected decision vectors has the same eigenvectors as the Hessian matrix. We further prove that when the population size is increased, the covariance becomes proportional to the inverse of the Hessian. We also devise and corroborate an analytic approximation of this covariance matrix. In the framework we consider, this confirms the classical hypothesis that learning the landscape is an inherent property of standard ESs, and that this capability stems only from the usage of isotropic Gaussian mutations and rank-based selection.
MicroRNA-122: A Novel Hepatocyte-Enriched in vitro Marker of Drug-Induced Cellular Toxicity

Emerging hepatic models for the study of drug-induced toxicity include pluripotent stem cell-derived hepatocyte-like cells (HLCs) and complex hepatocyte-non-parenchymal cellular coculture to mimic the complex multicellular interactions that recapitulate the niche environment in the human liver. However, a specific marker of hepatocyte perturbation, required to discriminate hepatocyte damage from non-specific cellular toxicity contributed by non-hepatocyte cell types or immature differentiated cells is currently lacking, as the cytotoxicity assays routinely used in in vitro toxicology research depend on intracellular molecules which are ubiquitously present in all eukaryotic cell types. In this study, we demonstrate that microRNA-122 (miR-122) detection in cell culture media can be used as a hepatocyte-enriched in vitro marker of drug-induced toxicity in homogeneous cultures of hepatic cells, and a cell-specific marker of toxicity of hepatic cells in heterogeneous cultures such as HLCs generated from various differentiation protocols and pluripotent stem cell lines, where conventional cytotoxicity assays using generic cellular markers may not be appropriate. We show that the sensitivity of the miR-122 cytotoxicity assay is similar to conventional assays that measure lactate dehydrogenase activity and intracellular adenosine triphosphate when applied in hepatic models with high levels of intracellular miR-122, and can be multiplexed with other assays. MiR-122 as a biomarker also has the potential to bridge results in in vitro experiments to in vivo animal models and human samples using the same assay, and to link findings from clinical studies in determining the relevance of in vitro models being developed for the study of drug-induced liver injury.
Vitamin K2 Regulation of Bone Homeostasis Is Mediated by the Steroid and Xenobiotic Receptor SXR*

Vitamin K2 is a critical nutrient required for blood clotting that also plays an important role in bone formation. Vitamin K2 supplementation up-regulates the expression of bone markers, increases bone density in vivo, and is used clinically in the management of osteoporosis. The mechanism of vitamin K2 action in bone formation was thought to involve its normal role as an essential cofactor for γ-carboxylation of bone matrix proteins. However, there is evidence that suggests vitamin K2 also has a transcriptional regulatory function. Vitamin K2 bound to and activated the orphan nuclear receptor SXR and induced expression of the SXR target gene, CYP3A4, identifying it as a bona fide SXR ligand. Vitamin K2 treatment of osteosarcoma cells increased mRNA levels for the osteoblast markers bone alkaline phosphatase, osteoprotegerin, osteopontin, and matrix Gla protein. The known SXR activators rifampicin and hyperforin induced this panel of bone markers to an extent similar to vitamin K2. Vitamin K2 was able to induce bone markers in primary osteocytes isolated from wild-type murine calvaria but not in cells isolated from mice deficient in the SXR ortholog PXR. We infer that vitamin K2 is a transcriptional regulator of bone-specific genes that acts through SXR to favor the expression of osteoblastic markers. Thus, SXR has a novel role as a mediator of bone homeostasis in addition to its role as a xenobiotic sensor. An important implication of this work is that a subset of SXR activators may function as effective therapeutic agents for the management of osteoporosis.
Seizure Clusters in Patients with Psychogenic Non-Epileptic Seizures

There is a paucity of literature concerning seizure clusters for patients who suffer from psychogenic, non-epileptic seizures (PNES). The purpose of the present study is threefold. Manuscript one will explore how seizure clusters may be defined for patients with PNES using both statistical and traditional approaches of cluster identification. Manuscript two will examine seizure clusters as a primary outcome in patients receiving treatment for PNES. Cluster reduction is examined longitudinally using traditional and statistical definitions of seizure cluster for patients. Possible risk factors for clustering will also be examined along with clustering as a risk factor for poorer secondary outcomes. Last, research is presently lacking concerning how to describe and explain seizure clusters in patients with PNES. Manuscript three will explore how clusters have been defined so far in both the epilepsy and PNES literatures. In addition, theories as to why seizures cluster for patients with PNES will also be considered. The aim of these studies is to provide a foundation from which research and theory on seizure cluster definition and explanation may be advanced for patient with PNES.
Study on the social psychology influencing factors of suicidal ideation in people living with AIDS

Objective To evaluate psychosocial factors and patterns on suicidal ideation of people living with AIDS in Anhui Province. Methods 175 AIDS patients were selected as the subjects. Data were collected using self-rating depressive scale (SDS), the APGAR, quality of life scale and a questionnaire designed by ourselves. Results 6.9%(12/175) of AIDS patients have self-inflicted wound or suicidal behavior previously, and 50.0% of AIDS patients' intention were free from pain, 35.4%(62/175) AIDS patients had thought suicide or deliberately injuried themselves in the past. The results of analysis showed that the quality of life, degree of depression were the significant predicting variables of self-injurious behavior (P0.05). The stepwise logistic regression analysis showed that sex, HIV-infected of spouse, family functioning, degree of depression were the significant predicting variables of suicidal ideation. Conclusions AIDS patients’ suicidal ideation to emerge is due to various social-psychic factors. An important way for decrease self-injurious behavior and suicidal ideation rate would be through improving family function and the degree of depression among people living with AIDS.
Exploiting Item Taxonomy for Solving Cold-Start Problem in Recommendation Making

Recommender systems' performance can be easily affected when there are no sufficient item preferences data provided by previous users, and it is commonly referred to as cold-start problem. This paper suggests another information source, item taxonomies, in addition to item preference data for assisting recommendation making. Item taxonomy information has been popularly applied in diverse ecommerce domains for product or content classification, and therefore can be easily obtained and adapted by recommender systems. In this paper, we investigate the implicit relations between users' item preferences and taxonomic preferences, suggest and verify that users who share similar item preferences may also share similar taxonomic preferences. Under this assumption, a novel recommendation technique is proposed that combines the users' item preferences and the additional taxonomic preferences together to make better quality recommendations as well as alleviate the cold-start problem. Empirical evaluations to this approach are conducted and the results show that the proposed technique outperforms other existing techniques in both recommendation quality and computation efficiency.
MUSICAL INSTRUMENT IDENTIFICATION IN CONTINUOUS RECORDINGS

Recognition of musical instruments in multi-instrumental, polyphonic music is a difficult challenge which is yet far from being solved. Successful instrument recognition techniques in solos (monophonic or polyphonic recordings of single instruments) can help to deal with this task. We introduce an instrument recognition process in solo recordings of a set of instruments (bassoon, clarinet, flute, guitar, piano, cello and violin), which yields a high recognition rate. A large and very diverse solo database (108 different solos, all by different performers) is used in order to encompass the different sound possibilities of each instrument and evaluate the generalization abilities of the classification process. First we bring classification results using a very extensive collection of features (62 different feature types), and then use our GDE feature selection algorithm to select a smaller feature set with a relatively short computation time, which allows us to perform instrument recognition in solos in real-time, with only a slight decrease in recognition rate. We demonstrate that our real-time solo classifier can also be useful for instrument recognition in duet performances, and improved using simple “source reduction”.
Timing the Mode Switch in a Sequential Mixed-Mode Survey

Mixed-mode surveys need to determine a number of design parameters that may have a strong influence on costs and errors. In a sequential mixed-mode design with web followed by telephone, one of these decisions is when to switch modes. The web mode is relatively inexpensive but produces lower response rates. The telephone mode complements the web mode in that it is relatively expensive but produces higher response rates. Among the potential negative consequences, delaying the switch from web to telephone may lead to lower response rates if the effectiveness of the prenotification contact materials is reduced by longer time lags, or if the additional e-mail reminders to complete the web survey annoy the sampled person. On the positive side, delaying the switch may decrease the costs of the survey. We evaluate these costs and errors by experimentally testing four different timings (1, 2, 3, or 4 weeks) for the mode switch in a web–telephone survey. This experiment was conducted on the fourth wave of a longitudinal study of the mental health of soldiers in the U.S. Army. We find that the different timings of the switch in the range of 1–4 weeks do not produce differences in final response rates or key estimates but longer delays before switching do lead to lower costs.
Uncomfortable Images in Art and Nature

The ratings of discomfort from a wide variety of images can be predicted from the energy at different spatial scales in the image, as measured by the Fourier amplitude spectrum of the luminance. Whereas comfortable images show the regression of Fourier amplitude against spatial frequency common in natural scenes, uncomfortable images show a regression with disproportionately greater amplitude at spatial frequencies within two octaves of 3 cycles deg−1. In six studies, the amplitude in this spatial frequency range relative to that elsewhere in the spectrum explains variance in judgments of discomfort from art, from images constructed from filtered noise, and from art in which the phase or amplitude spectra have been altered. Striped patterns with spatial frequency within the above range are known to be uncomfortable and capable of provoking headaches and seizures in susceptible persons. The present findings show for the first time that, even in more complex images, the energy in this spatial-frequency range is associated with aversion. We propose a simple measurement that can predict aversion to those works of art that have reached the national media because of negative public reaction.
Premium Gasoline Overbuying in the U.S.: Consumer-Based Choice Analysis

High octane gasolines, including â€œpremiumâ€ and midgrade, steadily gained market share in the United States during the 1980s, increasing from 12% of the total gasoline market in 1983 to 15% in 1985 and 30% in 1989. This 18% increase in market share represents an aggregate revenue transfer from U.S. consumers to industry of an additional $3 billion per year. It is widely believed that many drivers do not gain any benefit from using premium gasoline. We review the substantial technical evidence underlying this presumption, and then analyze a survey of vehicle owners in New York and California to determine why people purchase premium gasoline, given that many of them receive no clear benefit. We found that demand for premium gasoline is highly elastic, women and drivers in certain regions are more inclined to purchase premium gasoline, income plays a minor role, and the benefits are poorly understood. Many people buy premium gasoline for rather vague reasons, not on the basis of strong evidence or justification.
Temporal Stability of Genetic Variability and Differentiation in the Three-Spined Stickleback (Gasterosteus aculeatus)

Temporal variation in allele frequencies, whether caused by deterministic or stochastic forces, can inform us about interesting demographic and evolutionary phenomena occurring in wild populations. In spite of the continued surge of interest in the genetics of three-spined stickleback (Gasterosteus aculeatus) populations, little attention has been paid towards the temporal stability of allele frequency distributions, and whether there are consistent differences in effective size (Ne) of local populations. We investigated temporal stability of genetic variability and differentiation in 15 microsatellite loci within and among eight collection sites of varying habitat type, surveyed twice over a six-year time period. In addition, Nes were estimated with the expectation that they would be lowest in isolated ponds, intermediate in larger lakes and largest in open marine sites. In spite of the marked differences in genetic variability and differentiation among the study sites, the temporal differences in allele frequencies, as well as measures of genetic diversity and differentiation, were negligible. Accordingly, the Ne estimates were temporally stable, but tended to be lower in ponds than in lake or marine habitats. Hence, we conclude that allele frequencies in putatively neutral markers in three-spined sticklebacks seem to be temporally stable – at least over periods of few generations – across a wide range of habitat types differing markedly in levels of genetic variability, effective population size and gene flow.
Modified MLVA for Genotyping Queensland Invasive Streptococcus pneumoniae

Background Globally, over 800 000 children under five die each year from infectious diseases caused by Streptococcus pneumoniae. To understand genetic relatedness between isolates, study transmission routes, assess the impact of human interventions e.g. vaccines, and determine infection sources, genotyping methods are required. The ‘gold standard’ genotyping method, Multi-Locus Sequence Typing (MLST), is useful for long-term and global studies. Another genotyping method, Multi-Locus Variable Number of Tandem Repeat Analysis (MLVA), has emerged as a more discriminatory, inexpensive and faster technique; however there is no universally accepted method and it is currently suitable for short-term and localised epidemiology studies. Currently Australia has no national MLST database, nor has it adopted any MLVA method for short-term or localised studies. This study aims to improve S. pneumoniae genotyping methods by modifying the existing MLVA techniques to be more discriminatory, faster, cheaper and technically less demanding than previously published MLVA methods and MLST. Methods Four different MLVA protocols, including a modified method, were applied to 317 isolates of serotyped invasive S. pneumoniae isolated from sterile body sites of Queensland children under 15 years from 2007–2012. MLST was applied to 202 isolates for comparison. Results The modified MLVA4 is significantly more discriminatory than the ‘gold standard’ MLST method. MLVA4 has similar discrimination compared to other MLVA techniques in this study). The failure to amplify particular loci in previous MLVA methods were minimised in MLVA4. Failure to amplify BOX-13 and Spneu19 were found to be serotype specific. Conclusion We have modified a highly discriminatory MLVA technique for genotyping Queensland invasive S. pneumoniae. MLVA4 has the ability to enhance our understanding of the pneumococcal epidemiology and the changing genetics of the pneumococcus in localised and short-term studies.