Miracle-dz/UniFAR-FTUs huggingface dataset:
Revisiting Visual-Inertial Structure-From-Motion for Odometry and SLAM Initialization

In this letter, an efficient closed-form solution for the state initialization in visual-inertial odometry (VIO) and simultaneous localization and mapping (SLAM) is presented. Unlike the state-of-the-art, we do not derive linear equations from triangulating pairs of point observations. Instead, we build on a direct triangulation of the unknown <inline-formula><tex-math notation="LaTeX">$3D$</tex-math></inline-formula> point paired with each of its observations. We show and validate the high impact of such a simple difference. The resulting linear system has a simpler structure and the solution through analytic elimination only requires solving a <inline-formula><tex-math notation="LaTeX">$6\times 6$</tex-math></inline-formula> linear system (or <inline-formula><tex-math notation="LaTeX">$9 \times 9$</tex-math></inline-formula> when accelerometer bias is included). In addition, all the observations of every scene point are jointly related, thereby leading to a less biased and more accurate solution. The proposed formulation attains up to 50 percent decreased velocity and point reconstruction error compared to the standard closed-form solver, while it is <inline-formula><tex-math notation="LaTeX">$4\times$</tex-math></inline-formula> faster for a 7-frame set. Apart from the inherent efficiency, fewer iterations are needed by any further non-linear refinement thanks to better parameter initialization. In this context, we also present a non-linear optimizer that optionally refines the initial parameters. The superior performance of the proposed solver is established by quantitative comparisons with the state-of-the-art solver.
Formation of and Adherence to a Self-Disclosure Norm in an Online Chat

To understand how a norm of self-disclosure forms and is adhered to in a synchronous computer-mediated discussion, participants discussed the stigma of mental illness. The transcripts of the discussion were coded for the number of self-disclosures, the number of statements supportive of self-disclosure, and the number of statements supportive of non-self-disclosure. The results showed that the number of self-disclosing statements increased over time, although not in a linear fashion, as did the number of statements supportive of self-disclosure. However, the number of statements supportive of non-self-disclosures decreased over time. These results suggest that once a norm of self-disclosure forms, it is reinforced by statements supportive of self-disclosures but not of non-self-disclosures. The results are discussed in the context of self-disclosure reciprocity and the social identity model of deindividuation effects (SIDE).
The relationship between blood lead levels and morbidities among workers employed in a factory manufacturing lead–acid storage battery

The present study was carried out to find the relationship between blood lead levels (BLLs) and morbidities among 391 male workers employed in a factory manufacturing lead–acid storage batteries. A predesigned questionnaire was used to collect information on subjective health complaints and clinical observation made during a clinical examination. In addition to monitoring of BLL, other laboratory parameters investigated included hematological and urine-δ-aminolevulinic acid levels. Logistic regression method was used to evaluate the relationship between BLL and morbidities. The BLL among workers was associated with an odd ratio of respiratory, gastrointestinal (GI), and musculoskeletal (MSD) morbidities. Mean corpuscular hemoglobin and packed cell volume variables were associated with respiratory problems. The variables of alcohol consumption and hematological parameters were associated with GI complaints. Systolic blood pressure was related to MSD in workers exposed to Pb during the manufacturing process.
Single‐Molecule Spectroscopy for Plastic Electronics: Materials Analysis from the Bottom‐Up

π‐conjugated polymers find a range of applications in electronic devices. These materials are generally highly disordered in terms of chain length and chain conformation, besides being influenced by a variety of chemical and physical defects. Although this characteristic can be of benefit in certain device applications, disorder severely complicates materials analysis. Accurate analytical techniques are, however, crucial to optimising synthetic procedures and assessing overall material purity. Fortunately, single‐molecule spectroscopic techniques have emerged as an unlikely but uniquely powerful approach to unraveling intrinsic material properties from the bottom up. Building on the success of such techniques in the life sciences, single‐molecule spectroscopy is finding increasing applicability in materials science, effectively enabling the dissection of the bulk down to the level of the individual molecular constituent. This article reviews recent progress in single molecule spectroscopy of conjugated polymers as used in organic electronics.
IEEE Standard 802.19.1 for TV white space coexis tence

Understanding of the need to provide coexistence solutions for different cognitive radio systems operating in white space frequency bands, in December 2009 the IEEE 802 Executive Committee started project 802.19. 1 to develop a standard for "TV White Space Coexistence Methods". This standard, published in June 2014, specifies radio technology independent methods for coexistence among dissimilar or independently operated TV band networks. In this article we present the key concepts of the IEEE 802.19. 1 coexistence system, its architecture, and protocol. We also provide an example of the IEEE 802.19. 1 coexistence system implementation and operation.
Start-up shear of concentrated colloidal hard spheres: Stresses, dynamics, and structure

The transient response of model hard sphere glasses is examined during the application of steady rate start-up shear using Brownian dynamics simulations, experimental rheology and confocal microscopy. With increasing strain, the glass initially exhibits an almost linear elastic stress increase, a stress peak at the yield point and then reaches a constant steady state. The stress overshoot has a nonmonotonic dependence with Peclet number, Pe, and volume fraction, φ, determined by the available free volume and a competition between structural relaxation and shear advection. Examination of the structural properties under shear revealed an increasing anisotropic radial distribution function, g(r), mostly in the velocity-gradient (xy) plane, which decreases after the stress peak with considerable anisotropy remaining in the steady-state. Low rates minimally distort the structure, while high rates show distortion with signatures of transient elongation. As a mechanism of storing energy, particles are trapped within a cage distorted more than Brownian relaxation allows, while at larger strains, stresses are relaxed as particles are forced out of the cage due to advection. Even in the steady state, intermediate super diffusion is observed at high rates and is a signature of the continuous breaking and reformation of cages under shear.
Reflux and sex: what drives testing, what drives treatment?

Gastroesophageal reflux (GER) affects ∼10–20% of American adults. Although symptoms are equally common in men and women, we hypothesized that sex influences diagnostic and therapeutic approaches in patients with GER. PubMed database between 1997 and October 2011 was searched for English language studies describing symptoms, consultative visits, endoscopic findings, use and results of ambulatory pH study, and surgical therapy for GER. Using data from Nationwide Inpatient Sample, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, we determined the sex distribution for admissions and reflux surgery between 1997 and 2008. Studies on symptoms or consultative visits did not show sex-specific differences. Even though women are less likely to have esophagitis or Barrett's esophagus, endoscopic studies enrolled as many women as men, and women were more likely to undergo ambulatory pH studies with a female predominance in studies from the US. Surgical GER treatment is more commonly performed in men. However, studies from the US showed an equal sex distribution, with Nationwide Inpatient Sample data demonstrating an increase in women who accounted for 63% of the annual fundoplications in 2008. Despite less common or severe mucosal disease, women are more likely to undergo invasive diagnostic testing. In the US, women are also more likely to undergo antireflux surgery. These results suggest that healthcare-seeking behavior and socioeconomic factors rather than the biology of disease influence the clinical approaches to reflux disease.
The Relationship between Lute’s Choice Axiom, Thurstone’s Theory of Comparative Judgment, and the Double Exponential Distri butionl

Holman and Marley have shown that Thurstone’s Case V model becomes equivalent to the Choice Axiom if its discriminal processes are assumed to be independent double exponential random variables instead of normal ones. It is shown here that for pair comparisons, this representation is not unique; other discriminal process distributions (specifiable only in terms of their characteristic functions) also yield a model equivalent to the Choice Axiom. However, none of these models is equivalent to the Choice Axiom for triple comparisons: There the double exponential representation is unique. It is also shown that within the framework of Thurstone’s theory, the double exponential distribution, and hence the Choice Axiom, is implied by a weaker assumption, called “invariance under uniform expansions of the choice set. ”
Influence of Elastane Consumption on Plated Plain Knitted Fabric Characteristics

The requirements in terms of wearing comfort with sportswear underwear and outerwear are widely linked to the use of elastane fibers. Today, elastomeric plated jersey fabric is one of the most common fabrics produced with large-diameter circular knitting machine (LCKM). However, the relation between elastane proportion and fabric characteristics has not been enough studied in literature and knitters generally use experience during machines adjustments in to order reach needed fabric characteristics. The aim of this paper was to investigate the relation between Lycra® consumption and fabric dimensional and elastic behavior. The obtained results showed that Lycra® proportion inside fabric has an incidence on fabric width, weight and elasticity. The origin of this behaviour has been discussed.
Shoot Multiplication and in Vitro Rooting of Carlina onopordifolia Basser

This paper is the first published report describing micropropagation of Carlina onopordifolia, using shoot tip and hypocotyl explants. The explants were excised from 10-day-old seedlings and transferred to proliferation medium supplemented with 6-benzylaminopurine (BA; 1.0 or 3.0 mg l-1), kinetin (Kn; 1.0 or 3.0 mg l-1) or zeatin (ZEA; 1.0 or 3.0 mg l-1) in combination with naphthaleneacetic acid (NAA; 0.1 mg l-1). The shoot tips were significantly better than hypocotyls as initial material for shoot regeneration. For shoot multiplication, MS medium supplemented with BA proved superior to the other cytokinins tested. Medium supplemented with 1.0 mg l-1 BA gave the highest shoot propagation frequency (66.9%) and number of shoots per explant (2.5). Single shoots were separated from each other and rooted on MS supplemented with IBA for the whole period of culture, with longor short-pulse IBA application. The highest rooting frequency (84.8%) and root number (18.8) were for shortpulse (1 min) 1000 mg l-1 IBA solution. The higher IBA concentration stimulated callus formation and the development of short roots. The shoots were transferred to MS medium without growth regulators. Survival was highest (54.4%) for the plants from the short-pulse 100 mg l-1 IBA treatment. After 8 weeks of acclimatization the plantlets were removed to field conditions and grew normally.
Impact of step-based tutoring on student learning in linear circuit courses

A step-based tutoring system is being developed to improve student learning in elementary linear circuit analysis courses. The approach is based on the known importance of viewing worked examples or solutions in alternation with problem-solving exercises of the same type, to avoid excessive cognitive loads when learning a new skill. The system can generate an unlimited supply of circuit problems (with randomly varying topologies) similar to those in textbooks and corresponding fully explained solutions for both DC, AC, and transient analysis. Solution methods and topics include voltage and current division, node and mesh analysis, superposition, Thévenin and Norton equivalents, Bode plots, and Laplace analysis. Special pedagogical devices are used to reduce extraneous cognitive load when using the system, such as color-coding nodes and equation terms. Qualitative conceptual topics such as series and parallel connections are given special emphasis. The system has been used to date by over 2860 students in 71 class sections at 10 different colleges and universities of widely varying types, with generally very favorable student ratings. Evaluation has included a series of randomized, controlled trials in both laboratory and classroom settings to rigorously assess student learning gains as well as the impact of the materials on student motivation and preferences. Learning improvements of 0.72 std. deviations are found in comparison to a publisher-based homework system for node analysis, and 0.97 std. deviations for identification of elements in series and parallel compared to paper exercises.
On the Influence of the Choice of Channel on the Quality of Connections of IEEE 802.11g Networks

Wireless networks have almost reached omnipresence. Having multiple Wi-Fi (Wireless Fidelity) hotspots in a single building has become a commonplace, and this rapid growth has impact on the way network engineers organize and place the network elements. This paper is based on experimental data acquired in an indoor environment, as a way to evaluate the quality of connection and transmissions among IEEE 802.11g networks, using off the shelf devices. The collected data reveals that the choice of channel influences the throughput and has impact on network availability in a noisy environment.
Perturbation analysis explained

This note provides a simple explanation of the ideas behind perturbation analysis. Perturbation Analysis (PA) is a technique for the computation of the gradient of performance measure (PM) of a discrete event dynamic system with respect to its parameters (e) using only one sample path or Monte Carlo experiment of the system. When first presented, one's immediate reaction has often been incredulity stemming from the belief that "one cannot get something for nothing". Later this disbelief may be developed into a more sophisticated and technical objection involving the legitimacy of interchanging differentiation and expectation operators or the probabilistic convergence of the PA estimate to its true value (more about these later). In nontechnical terms, these translate to "How can you squeeze out information about a trajectory / sample-path operating under one value of the system parameter from that of another operating under a different value? Don't the two trajectories behave entirely dissimilarly? " We shall offer below a simple explanation. This explanation covers the essence of PA in the simplest terms stripped of all of its computational trappings, efficiency tricks, etc. Once the basic ideas are made clear, we leave the question of "how efficient" to other papers and potential implementors. For similar tutorial reasons, the example used below is not at all the most general case for which PA can be applied. The purpose here is to convey the fundamental idea behind this approach in terms accessible to the largest audience. Interested readers are referred to other PA papers which at this point total over 40 (see [7],[8]).
¿Son las estrategias genéricas y las barreras a la entrada ventajas competitivas en estos tiempos? : El caso de las industrias de alimentos, bebidas, tabaco y química en México (2009-2014).

El articulo analiza las sub-ramas industriales que pertenecen a las ramas de alimentos, bebidas, tabaco y quimica, las cuales pertenecen al sector industrial de manufacturas en Mexico, segun datos del Censo Economico Industrial del Instituto Nacional de Geografia y Estadistica (INEGI). El objetivo es evaluar si los requerimientos de capital y las erogaciones asociadas al desempeno de las estrategias genericas tienen un desempeno superior mediante ventas y si las mencionadas afectan a la cantidad de empresas incumbentes o competidoras en las sub-ramas analizadas. Las tecnicas empleadas fueron dos regresiones de corte transversal para los periodos censales de 2009 y 2014. Los hallazgos indican que los requerimientos de capital tienen efectos positivos en las ventas y negativos en la cantidad de competidores, es decir son ventajas sostenibles porque estan asociadas a los beneficios y permiten monopolizar sus sectores industriales (barreas a la entrada).
Treatment adherence and patient retention in the first year of a Phase-III clinical trial for the treatment of multiple sclerosis

The purpose of this study was to examine the relationship between patient management strategies employed by study personnel, and patient retention and adherence to treatment in the first year of a Phase III clinical trial of interferon beta-1b for treatment of secondary progressive multiple sclerosis (MS). Study staff from each of 35 sites were interviewed regarding patient management practices. Sites which were rated as more empathetic, as instilling a sense of purpose in the patient, and promoting less formal relationships with patients had high rates of adherence to treatment. In addressing specific patient concerns, attention to patients' emotional status and patients' expectations of trial participation were related to better adherence.
Phagocyte function in juvenile periodontitis

We studied the chemotaxis of peripheral blood polymorphonuclear leukocytes (PMNs) and monocytes and the production of tumor necrosis factor alpha by monocytes of patients with juvenile periodontitis (JP). As a group, the patients' PMNs showed significantly increased chemotaxis determined by counting the number of migrating cells within a 3-microns-pore-size filter. Determined as distance of migration within the filter, as chemotactic increment based on checkerboard analysis, as leukotactic index calculated on the basis of distance of migration and cell count at different depths within a 3-microns-pore-size filter, as distance of migration under agarose, and as the number of PMNs migrating across a 5-microns-pore-size filter, the chemotactic migration rates of PMNs of patients were similar to those of controls. Evaluation of the data on an individual basis suggested that in terms of PMN chemotaxis some patients were hyperresponsive and some were hyporesponsive. Chemotaxis, spontaneous migration, and the rates of lipopolysaccharide-induced tumor necrosis factor alpha production by JP monocytes were similar to those of control cells. Our results give credence to the view that there are minor aberrations in the functions of JP phagocytes, but the extent to which these aberrations are relevant to accumulation of PMNs at sites of infection and inflammation in vivo and possibly contribute to the pathogenesis of JP remains unclear.
Experiments on how photo- and background ionization affect positive streamers: oxygen concentration, repetition and radioactivity

Positive streamers in air and other oxygen-nitrogen mixtures are generally believed to propagate against the electron drift direction due to photo-ionization. Photo-ionization is the non-local ionization of O2-molecules by UV radiation from excited N2-molecules. This facilitates the streamer propagation by creating free electrons ahead of it. The relative importance of photo-ionization depends on the O2/N2 ratio. Another possible source of free electrons in front of the positive streamer is background ionization. This can be ionization left by previous discharges or by other processes such as cosmic rays or (natural) radio-activity. We study the effects of both photo- and background-ionization on propagation and morphology of positive streamers by changing gas composition and repetition frequency. One particular gas composition is pure nitrogen with a small amount of radio-active 85Kr added to increase background ionization.
User Involvement as an Interaction Process: A Case Study

User involvement is recommended to analysts as a technique of successful system development, but as a process it is little understood. This case study compares four process models of user involvement–learning, conflict, political and garbage-can-with each other and with an empirical example of system development. Different models are seen as appropriate to explaining the nature of user involvement in different stages of development and contexts. Structural conditions and issues of power are shown to be decisive in the development of conflict and conflict resolution. A two-stage model of user involvement based on Robey and Farrow's work (1982) is proposed which distinguishes conflict development from conflict resolution.
A review of Acceptance and Commitment Therapy (ACT) empirical evidence: Correlational, experimental psychopathology, component and outcome studies.

This article analyzes the general empirical evidence concerning Acceptance and Commitment Therapy (ACT). In the first place, a brief description of the ACT philosophical and theoretical roots is presented. Subsequently, the most fundamental characteristics of the ACT model for psychological intervention are described. Then, a review of the correlational, experimental psychopathology and component, and outcome studies that are relevant for the ACT model empirical status is exposed. In general, the evidence regarding all these types of studies is very coherent and supports the ACT model. Specifically, experiential avoidance is found to be related with a wide range of psychological disorders and mediates the relation between different type of symptoms and psychological constructs; component studies are showing that acceptance-based protocols are usually more efficacious than other control-based protocols; outcome studies show the efficacy of ACT in a wide range of psychological problems and suggest that it is working through its hypothesized processes of change. However, the limitations of the actual empirical status of ACT are recognized and further research is emphasized.
New advances in acute graft‐versus‐host disease prophylaxis

Summary. Immunocompetent donor T cells in Allogeneic Haematopoietic Stem Cell grafts mediate acute Graft versus Host Disease (GvHD), still a major cause of recipient morbidity and mortality post transplant. Despite the advent of high resolution HLA‐typing and matching at HLA loci, acute GvHD remains a significant problem, even in HLA matched siblings, due primarily to minor histocompatability antigen mismatches. Treatment of GvHD remains ineffective and highly immunosuppressive and the challenge to find effective methods of prevention continues. Non selective removal of donor T cells from the graft has been proven to be effective in preventing GvHD but the beneficial effects of donor T cells, namely effective immune reconstitution and anti tumour activity, are lost. This review considers mechanisms by which acute GvHD may be prevented in the context of the current model of GvHD immunopathogenesis, with a special emphasis on the recent techniques of selective removal or destruction of donor allogeneic T cells that have been described.