Miracle-dz/UniFAR-FTUs huggingface dataset:
Sampling from large matrices: An approach through geometric functional analysis

We study random submatrices of a large matrix <i>A</i>. We show how to approximately compute <i>A</i> from its random submatrix of the smallest possible size <i>O</i>(<i>r</i>log <i>r</i>) with a small error in the spectral norm, where <i>r</i> = ‖<i>A</i>‖<sup>2</sup><sub><i>F</i></sub>/‖<i>A</i>‖<sup>2</sup><sub>2</sub> is the numerical rank of <i>A</i>. The numerical rank is always bounded by, and is a stable relaxation of, the rank of <i>A</i>. This yields an asymptotically optimal guarantee in an algorithm for computing <i>low-rank approximations</i> of <i>A</i>. We also prove asymptotically optimal estimates on the <i>spectral norm</i> and the <i>cut-norm</i> of random submatrices of <i>A</i>. The result for the cut-norm yields a slight improvement on the best-known sample complexity for an approximation algorithm for MAX-2CSP problems. We use methods of Probability in Banach spaces, in particular the law of large numbers for operator-valued random variables.
Variable bit rate VOiP in IEEE 802.11e wireless LANs

WLANs have become a ubiquitous networking technology deployed everywhere. Meanwhile. VoIP is one popular application and a viable alternative to traditional telephony systems due to its cost efficiency. VoIP over WLAN (VoWLAN) has been emerging as an infrastructure to provide low-cost wireless voice services. However, VoWLAN poses significant challenges due to the characteristics of contention-based protocols and wireless networks. In this article we propose two mechanisms to provide quality of service for variable bit rate VoIP in IEEE 802.11e contention-based channel access WLANs: access time-based admission control and access point dynamic access. Simulation results are conducted to study these schemes.
Hybrid damping of grid-tie inverter output harmonics for resonance rejection & wind park stability under high penetration

Grid-tie inverters are usually connected to Pad-Mount Transformers (PMT) through passive filters. Most grid-tie inverter manufacturers design these passive filters to eliminate high frequency current ripples and switching harmonics generated by the switching actions of inverters. Under high wind power penetration output power filters are susceptible to create severe resonance due to their interaction with the grid voltage harmonics and transmission line impedances. This resonance generates high harmonics which are not only not in compliance with the IEEE 519 power quality requirement, but also are very harmful to power system components. This paper proposes a hybrid damping approach which combines the passive damping of the filter with a physical resistor and an active damping of the inverter output harmonics with grid voltage harmonics feed-forward. The approach takes into account the passive filters interaction with the grid through impedance analysis under high wind power penetration. Simulations and field tests are shown to demonstrate the validity of the proposed approach.
Reassessing the construct validity of a Brazilian version of the instrument Caregiver Abuse Screen (CASE) used to identify risk of domestic violence against the elderly

Background: Domestic violence against the elderly (DVAE) is an increasingly recognised problem and its appropriate detection is imperative. As part of an ongoing cross-cultural adaptation process, this study evaluates the construct validity of a Brazilian Portuguese version of the instrument Caregiver Abuse Screen (CASE). Methods: A cross-sectional study comprising 507 pairs of caregivers/elderly patients was carried out in three geriatric outpatient units. A multidimensional questionnaire was completed for each pair of interviewees covering DVAE, sociodemographic characteristics and several theory-related variables (alcohol misuse, burden, depression, social support, cognitive status, instrumental activities of daily living, general health status and living arrangements). Sequential confirmatory and exploratory factor analyses (CFA/EFA) were implemented to assess construct validity through an in-depth exploration of the instrument’s dimensional structure. Construct validity was also assessed through relationships with other variables. Results: The initial CFA did not support the postulated two-factor solution. A one-dimensional solution suggested by an EFA was followed by a CFA, which showed adequate fit (WRMR = 0.985, RMSEA = 0.056, CFI = 0.967 and TLI = 0.969), internal consistency (ρcr = 0.85) and temporal stability (κw = 0.77). Yet, convergent validity was not achieved (average variance extracted <0.50; ρve = 0.45). Using Kendall’s Tau-b correlations, the CASE was positively associated with two other instruments assessing DVAE (H/S-EAST: τb = 0.13; and CTS-1 subscales: τb = 0.15−0.37); caregiver burden (Zarit BI: τb = 0.40); and depression (GDS: τb = 0.32). Conclusion: In spite of some remaining dimensionality issues needing refinement and the relatively restricted correlations with expected variables, the CASE may be reaffirmed as a promising detection tool for risk of abuse in clinical practice and applied research.
Improved extended Kalman fusion method for upper limb motion estimation with inertial sensors

With the rapid development of microsensors, the real-time, low-cost human motion tracking system using inertial sensors has become more and more popular. Because of the complicated indoor electromagnetic environment, magnetic disturbance has become one of the most challenging issues. This paper presents a portable real-time limb motion capture system based on extended kalman filter. In this system, a non-linear two step algorithm is used to calibrate the magnetometer. And an adaptive mechanism for weighting the measurements is introduced in the EKF to reduce the impact of the body motion and temporary magnetic disturbances. Simulation and experimental results have shown that the proposed algorithm obtains good performance in magnetically disturbed environment.
Identification of a conjunctivitis-associated gene locus from the virulence plasmid of Yersinia enterocolitica

The virulence plasmid (pYV) of Yersinia enterocolitica is necessary for production of conjunctivitis in guinea pigs and for mouse lethality. To identify the genes responsible for production of conjunctivitis in guinea pigs, we subcloned the BamHI and SalI restriction fragments of the virulence plasmid of Y. enterocolitica A2635 (serotype O:8) into derivatives of the broad-host-range plasmid pRK290 and introduced the constructions into plasmid-negative Y. enterocolitica strains. A mild, transient conjunctivitis was evident 24 h after inoculation with strains containing a 2.8-kilobase (kb) BamHI fragment of pYV. These strains were cytotoxic to HEp-2 cells but did not cause death in iron-loaded adult mice. When the 2.8- and adjacent 0.5-kb BamHI fragments were deleted from the virulence plasmid of a fully virulent Y. enterocolitica isolate, the resultant strain did not cause conjunctivitis in guinea pigs and was not cytotoxic to HEp-2 cells. However, the strain with the deletion appeared to be more virulent for mice, with more rapid dissemination after orogastric inoculation, compared with that of the parent strain. When the deletion was complemented by introduction of a plasmid containing the 2.8-kb BamHI fragment, the strain again caused conjunctivitis but had decreased virulence for mice.
Toward Low-Power Flash Memory: Prospect of Adopting Crystalline Oxide as Charge Trapping Layer

The rapid growth of data center, ubiquitous cloud computing, and mobile gadgets has made flash memory one of the major semiconductor markets. The booming request of flash memory has not only brought substantial economic and societal benefit but led to growing power consumption. The operation voltage of existent flash memory is in the range of 15-17 V which still has much room to be reduced to save power while ensuring environmental sustainability. To enable flash memory at lower voltage, developing innovative materials and structures is a prerequisite. Recently, crystalline oxide is extensively developed as a novel charge trapping layer (CTL) and holds the prospect of becoming a promising candidate for memory applications by demonstrating operation voltage lower than 10 V. In this paper, how crystalline oxide in the form of high-k dielectric and semiconductor material can be employed in flash memory as the CTL to reduce the operation voltage and the mechanism to achieve this goal are reviewed. From the good memory performance in terms of a large memory window of 1.5 V by programming/erasing at voltage lower than 10 V for 1 ms, endurance more than 105 operation cycles, desirable retention at 85°C, employing crystalline oxide as the CTL has ushered in a new field to implement green flash memory devices.
Effects of exposure duration and recovery time during pulsed exposures

In pulsed toxicant exposures, the concentration, duration, and frequency of pulses can change through time. However, the conventional median lethal concentration (LC50) method cannot adequately predict the effects of pulsed exposure, because it is associated with fixed exposure duration and constant concentration and does not include postexposure (latent) mortality. Many studies that tried to address the effects of pulsed exposure only provided qualitative or semiquantitative predictions. Survival time experiments conducted here quantified the effect of exposure duration on latent mortality, and the effect of recovery time between two pulses on mortality during a second pulse also was examined. This was done by exposing amphipods (Hyalella azteca) to two contrasting toxicants, copper sulfate (CuSO4) and sodium pentachlorophenol (NaPCP). In the exposure duration experiments, the amphipods were exposed to two toxicant concentrations for three durations. No significant effect of duration on latent mortality was detected within the experimental range; however, duration still may need to be considered under other conditions. In the recovery time experiments, the amphipods were provided four recovery times, and their survivals during the second exposure were modeled. Recovery time had a significant effect on the second‐exposure mortality. Given enough time, the amphipods could recover to a state similar to their original toxicant resistance state. The complete recovery time for CuSO4 was fivefold longer than that for NaPCP. It is important to quantify the effects of latent mortality, pulse duration and concentration, and recovery time for pulsed exposures. Survival analysis provides a better way to address these issues than does the conventional LC50 method.
QuEst - A translation quality estimation framework

We describe QUEST, an open source framework for machine translation quality estimation. The framework allows the extraction of several quality indicators from source segments, their translations, external resources (corpora, language models, topic models, etc.), as well as language tools (parsers, part-of-speech tags, etc.). It also provides machine learning algorithms to build quality estimation models. We benchmark the framework on a number of datasets and discuss the efficacy of features and algorithms.
Hydrolytic enzymes of Moraxella bovis

Certain strains of Moraxella bovis produce tissue-damaging enzymes which may initiate or potentiate infectious bovine keratoconjunctivitis. Thirteen reference strains of this species were characterized physiologically and screened for production of various enzymes by some conventional biochemical tests and the API ZYM system (Analytab Products, Plainview, N.Y.). All 13 strains were hemolytic. All hydrolyzed Tween 80 and Tween 85 and displayed C4 esterase, C8 esterase-lipase, and C14 lipase activities. All produced phosphoamidase and phosphatase. All were able to hydrolyze casein and gelatin. All produced leucine and valine aminopeptidases and fibrinolysin. Twelve produced hyaluronidase or were agarolytic. Three hydrolyzed chondroitin sulfate. Nine strains autoagglutinated. Five produced catalase, and two produced cystine aminopeptidase.
The Association between Serum Leptin and Post Stroke Depression: Results from a Cohort Study

Background Depression is a frequent mood disorder that affects around a third of stroke patients and has been associated with poorer outcomes. Our aim was to determine whether there was a relationship between inflammatory markers (leptin) and post-stroke depression (PSD). Methods One hundred and ninety-one ischemic stroke patients admitted to the hospital within the first 24 hours after stroke onset were consecutively recruited and followed up for 3 months. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of leptin at admission. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for post-stroke depression at 3 month. Results Forty-four patients (23.0%) were diagnosed as having major depression at 3 month. Patients with depression showed higher serum leptin levels at 3 month after stroke (32.2 [IQR, 20.8–57.7] v. 9.9 [IQR, 4.6–13.1]ng/ml, respectively; P = 0.000). Serum levels of leptin ≥20 ng/ml were independently associated with PSD [odds ratio (OR) 20.23, 95% confidence interval (CI) 9.11–51.26, P = 0.000], after adjusting for possible confounders. Conclusions Serum leptin levels elevated at admission were found to be associated with PSD and may provide a new proposal for the treatment of PSD.
A method for determining the non-existence of a common quadratic Lyapunov function for switched linear systems based on particle swarm optimisation

The existence of a common quadratic Lyapunov function (CQLF) for a switched linear system guarantees its global asymptotic stability. Even if progress in finding the conditions for the existence/non-existence of a CQLF is significant, especially in switched linear systems consisting of N second-order systems or two systems of order n, the general case of N systems of order n still remains open. In this article, a sufficient condition for the non-existence of a CQLF for N systems of order n is derived. Based on the condition, a new method for determining the non-existence of a CQLF, using particle swarm optimisation, was designed and is described. Examples illustrating the proposed method are introduced at the end of this article.
The Idiopathic Pulmonary Fibrosis Honeycomb Cyst Contains A Mucocilary Pseudostratified Epithelium

Background We previously identified a MUC5B gene promoter-variant that is a risk allele for sporadic and familial Idiopathic Pulmonary Fibrosis/Usual Interstitial Pneumonia (IPF/UIP). This allele was strongly associated with increased MUC5B gene expression in lung tissue from unaffected subjects. Despite the strong association of this airway epithelial marker with disease, little is known of mucin expressing structures or of airway involvement in IPF/UIP. Methods Immunofluorescence was used to subtype mucus cells according to MUC5B and MUC5AC expression and to identify ciliated, basal, and alveolar type II (ATII) cells in tissue sections from control and IPF/UIP subjects. Staining patterns were quantified for distal airways (Control and IPF/UIP) and in honeycomb cysts (HC). Results MUC5B-expressing cells (EC) were detected in the majority of control distal airways. MUC5AC-EC were identified in half of these airways and only in airways that contained MUC5B-EC. The frequency of MUC5B+ and MUC5AC+ distal airways was increased in IPF/UIP subjects. MUC5B-EC were the dominant mucus cell type in the HC epithelium. The distal airway epithelium from control and IPF/UIP subjects and HC was populated by basal and ciliated cells. Most honeycombing regions were distinct from ATII hyperplasic regions. ATII cells were undetectable in the overwhelming majority of HC. Conclusions The distal airway contains a pseudostratified mucocilary epithelium that is defined by basal epithelial cells and mucus cells that express MUC5B predominantly. These data suggest that the HC is derived from the distal airway.
Promoting reflection and interpretation in education: curating rich bookmarks as information composition

Reflection, interpretation, and curation play key roles in learning, creativity, and problem solving. Reflection means looking back and forward among building blocks constituting a space of ideas, contextualizing with processes including tasks, activities, and one's internal thinking and meditating, and deriving new understandings, known as interpretations. Curation, in the digital age, means searching, gathering, collecting, organizing, designing, reflecting on, and interpreting information. We introduce rich bookmarks, representations of key ideas from documents as navigable links that integrate visual clippings and rich semantic metadata. We support curating rich bookmarks as information composition. In this holistic visual form, curators express relationships among curated elements through implicit visual features, such as spatial position, color, and translucence. We investigated the situated context of a university course, engaging educators in iterative co-design. Rich bookmarks emerged in the process, motivating changes in pedagogy and software. Changes provoked students to collect more novel and varied ideas. They reported that curating rich bookmarks as information composition helped them reflect, transforming prior ideas into new ones. The visual component of rich bookmarks was found to support multiple interpretations; the semantic to support associational exploration of related ideas.
Sensibility Ergonomics Design Recommendation System Using Weather WebBot

Analysis of a customer's sensibility and preferences is an important strategy in a market that is becoming increasingly more customer oriented. In this paper, we propose the sensibility ergonomics design recommendation system using weather Web-Bot (DRS-WB). The proposed method applies sensibility ergo-nomics to increase the efficiency of merchandising for human-oriented sensible product designs. Development of DRS-WB used a user interface and collaborative filtering for the textile and fashion designs in order to satisfy the user's needs. Collaborative filtering was adopted in order to recommend designs of interest for users based on the predictive relationship discovered between the current user and other previous users. The today weather information is simultaneously acquired from the sensor based smartwear and the weather WebBot (Web Robot Agent). The weather WebBot uses a database of weather forecast information extracted from the web pages and RSS of the Korea Meteorologi-cal Administration and collects information from the various links off the main URL. And its signals are transmitted to the connected DRS-WB. It can be easily monitored in real time. We used 60 textile designs and 41 fashion designs in the survey ques-tionnaire. The composition of the questionnaire is 17 sections for 6 designs on a page. 2,830,020 ratings were collected from 1,401 users. The pictures of fashion design details, such as collar type, sleeve type, skirt type, skirt length, and color tone were evaluated in terms of sensibility. Ultimately, this paper suggests empirical applications to verify the adequacy and the validity of this system.
The effects of some antioxidant vitamin‐ and trace element‐supplemented diets on activities of SOD, CAT, GSH‐Px and LPO levels in chicken tissues

The effect of diets containing antioxidant vitamins and trace elements on chicken tissue activities of SOD, CAT, GSH‐Px and of LPO levels was investigated. Chickens, 45 weeks of age were divided into six groups: control group, Cu group (13.2 mg Cu kg−1 diet); Se group (0.07 mg Se kg−l diet); vitamin E group (70 mg DL‐α‐tocopherol acetate kg−1 diet) and a constant level vitamin C, 200 mg kg−1 diet); vitamin A group (240 mg retinol acetate kg−1 diet) and vitamin C group (500 mg ascorbic acid kg−1 diet).
Human NK cells display major phenotypic and functional changes over the life span

Aging is generally associated with an increased predisposition to infectious diseases and cancers, related in part to the development of immune senescence, a process that affects all cell compartments of the immune system. Although many studies have investigated the effects of age on natural killer (NK) cells, their conclusions remain controversial because the diverse health status of study subjects resulted in discordant findings. To clarify this situation, we conducted the first extensive phenotypic and functional analysis of NK cells from healthy subjects, comparing NK cells derived from newborn (cord blood), middle‐aged (18–60 years), old (60–80 years), and very old (80–100 years) subjects. We found that NK cells in cord blood displayed specific features associated with immaturity, including poor expression of KIR and LIR‐1/ILT‐2 and high expression of both NKG2A and IFN‐γ. NK cells from older subjects, on the other hand, preserved their major phenotypic and functional characteristics, but with their mature features accentuated. These include a profound decline of the CD56bright subset, a specific increase in LIR‐1/ILT‐2, and a perfect recovering of NK‐cell function following IL2‐activation in very old subjects. We conclude that the preservation of NK cell features until very advanced age may contribute to longevity and successful aging.
A Fast Analytical Algorithm for Solving Markov Decision Processes with Real-Valued Resources

Agents often have to construct plans that obey deadlines or, more generally, resource limits for real-valued resources whose consumption can only be characterized by probability distributions, such as execution time or battery power. These planning problems can be modeled with continuous state Markov decision processes (MDPs) but existing solution methods are either inefficient or provide no guarantee on the quality of the resulting policy. We therefore present CPH, a novel solution method that solves the planning problems by first approximating with any desired accuracy the probability distributions over the resource consumptions with phasetype distributions, which use exponential distributions as building blocks. It then uses value iteration to solve the resulting MDPs by exploiting properties of exponential distributions to calculate the necessary convolutions accurately and efficiently while providing strong guarantees on the quality of the resulting policy. Our experimental feasibility study in a Mars rover domain demonstrates a substantial speedup over Lazy Approximation, which is currently the leading algorithm for solving continuous state MDPs with quality guarantees.
Response to Hays et al and McHorney and Cohen: A Discussion of Item Response Theory and Its Applications in Health Status Assessment

We read with great interest the 2 articles on the use of item response theory (IRT) measurement models in the arena of health status assessment. For reasons that are more accidental than logical, classic approaches have dominated health status assessment until very recently. Now, IRT is entering the field. This is accompanied by enthusiasm for the prospect of deriving better definitions of underlying constructs, new hope for the prospect of individual diagnosis, and an opportunity to turn our attention away from static tests and scales to items and the incremental information they provide. The careful use of IRT-based assessment, either by preselecting an item list that applies to the population being studied, or by computerized adaptive testing (CAT) can make assessment briefer, more flexible, more efficient, and if desired, more precise than conventional approaches.