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This paper presents numerical simulations within the frame of the project SERA—AIMS (Seismic Testing of Adjacent Interacting Masonry Structures). The study includes blind pre-diction and post-diction stages. The former was developed before performing the shaking table tests at the laboratory facilities of LNEC (Lisbon), while the latter was carried out once the test results were known. For both, three-dimensional finite element models were prepared following a macro-modelling approach. The structure consisted of a half-scaled masonry aggregate composed by two units with different floor levels. Material properties used for the pre-diction model were based on preliminary tests previously provided to the participants. The masonry constitutive model used for the pre-diction study reproduced classical stress–strain envelope, whereas a more refined model was adopted for the post-diction. After eigenvalue analysis, incremental nonlinear time history analysis was performed under a unique sequence based on the given load protocol to account for damage accumulation. In the post-diction, the numerical model was calibrated on the data recorded during the shaking table tests and nonlinear dynamic analysis repeated under the recorded accelerogram sequence. The interaction between the two units was simulated through interface elements. Moreover, the timber floors were accounted following different strategies: not modelling or considering nonlinear wall-to-floor connections. Advantages and disadvantages are then analysed, comparing the pre-diction and post-diction results with the experimental data. Numerical results differ from the experimental outcomes regarding displacements and interface pounding, although a clear improvement is visible in the post-diction model. [ABSTRACT FROM AUTHOR]

Inertial confinement fusion experiments taking place at the National Ignition Facility are generating ever increasing amounts of fusion energy, with the deuterium tritium fusion neutron yield growing a hundredfold over the past ten years. Strategies must be developed to mitigate this harsh environment's deleterious effects on the operation and the performance of the time-resolved x-ray imagers deployed in the National Ignition Facility target bay to record the dynamics of the implosions. We review the evolution of these imagers in recent years and detail some of the past and present efforts undertaken to maintain or improve the quality of the experimental data collected on high neutron yield experiments. These include the use of a dump-and-read electronic backend, the selection of photographic film with a low background sensitivity, and the optical filtering of Cherenkov radiation. [ABSTRACT FROM AUTHOR]

In this study, BiVO4 particles were synthesized via the combustion method using orange peel powder as a fuel for photocatalytic methylene blue (MB) degradation. The novelty lies in using biomass as a fuel source and leveraging orange peel phytochemicals as stabilizing and complexing agents, eliminating the need for nitric acid required in conventional methods. XRD patterns showed that the orange peel promotes ternary phase formation (Dreyerite and Clinobisvanite phases), while urea supports the binary and ternary phase combination (i.e., V6O13 and BiVO4). Raman, XPS, and FTIR analyses confirmed the BiVO4 monoclinic phase formation using both fuels, with a band gap of approximately 2.4 eV. Increasing annealing temperature reduced structural disorder, V–O bond length, and surface area, which are more pronounced with orange peel. Photocatalytic experiments revealed the significant MB removal by adsorption with urea, while orange peel primarily drove photocatalysis in both cases, following a pseudo-first-order kinetic model. Scavenger experiments showed holes as the main reactive species promoting MB degradation. With a rise in catalyst dosage, removal is primarily enhanced through adsorption, confirmed by dark condition experiments. The BiVO4 sample annealed at 350 ºC with orange peel fuel exhibited the best photocatalytic performance that can completely remove MB after 270 min under 200 W LED light. [ABSTRACT FROM AUTHOR]

A limited amount of data exists on the cyclic behavior of concrete-filled steel deck diaphragms, and the few historical testing programs that have been conducted used specimens that may not be representative of modern floor assemblies typical in North America. As part of a larger research project, the Steel Diaphragm Innovation Initiative, an experimental program was conducted to fill critical knowledge gaps related to the behavior and design of concrete-filled steel deck diaphragms leading to a better understanding of the seismic performance of steel buildings utilizing these types of diaphragms. The experimental program included eight diaphragm specimens that were approximately 4 m by 5 m, tested in a cantilever test setup wherein one edge is restrained against translation while the opposing edge is subjected to an in-plane cyclic displacement history. Parameters that were varied included deck height (51 mm and 76 mm), concrete cover over the deck (51 mm to 115 mm), concrete type (normal weight and lightweight), configuration of perimeter headed shear studs, and the presence and amount of reinforcing steel. Specimen behavior was quantified including initial stiffness, peak shear strength, ductility, and energy dissipation and qualitatively connected to observed cracking and deformations. The results of this experimental program, combined with tests from the literature were used to develop proposed expressions for peak shear strength and initial stiffness. The proposed expressions reasonably capture the experimental results and are suitable for design. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the lived experiences of Latinx cancer survivors and their family caregivers during survivorship. Eighteen semi-structured interviews were conducted with a variety of stakeholders including Latinx cancer survivors (n = 8), their family caregivers (n = 5), and cancer care providers (n = 5). Data were analyzed thematically to describe occupational participation. Latinx families lived in political, economic, language, and social contexts that facilitated and hindered their well-being. Survivors simultaneously experienced occupational deprivation and posttraumatic growth. To promote occupational justice, occupational therapy practitioners and researchers are called to partner with Latinx survivors and their families to facilitate skills needed for everyday participation. [ABSTRACT FROM AUTHOR]

Background: Human cytomegalovirus (HCMV) is a worldwide infection, causing different troublesome in immunosupressed patients and very related to Human Immunodeficiency Virus 1 (HIV-1) infection, mainly in developing countries, with a co-infection rate of 80% in Africa. The high cost of present treatments and the lack of routinely tests in these countries urge the necessity to develop new molecules or strategies against HCMV. The new treatments should be low-cost and capable of avoiding the emerging problem of resistant virus. Nanoparticles play an important role in several viral infections. Our main focus is to study the potential activity of polyanionic carbosilane dendrimers (PDC), which are hyperbranched molecules with several sulfonate or sulfate groups in their periphery, against different viruses. Results: We studied the activity of G1-S4, G2-S16 and G2-S24P PDCs in MRC-5 cell line against HCMV infection by several plaque reduction assays. Our results show that dendrimers present good biocompatibility at the concentrations tested (1–50 µM) for 6 days in cell culture. Interestingly, both G2-S16 and G2-S24P showed a remarked inhibition at 10 µM against HCMV infection. Results on attachment and virucidal assays indicated that the inhibition was not directed to the virus or the virus-cell attachment. However, results of time of addition, showed a longer lasting activity of these dendrimers in comparison to ganciclovir, and the combination of G2-S16 or G2-S24P with ganciclovir increases the HCMV inhibition around 90 %. Conclusions: Nanotechnology, in particular polyanionic carbosilane dendrimers, have proved their potential application against HCMV, being capable of inhibiting the infection by themselves or enhancing the activity of ganciclovir, the actual treatment. These compounds represent a low-cost approach to fight HCMV infections. [ABSTRACT FROM AUTHOR]

This article employs a sociomaterial perspective adapted from information systems and management studies to examine the potential impact of body worn cameras (BWCs) on police organisations. Based on 42 semi-structured interviews with police employees, the study illustrates how wearable camera technology is seen to 'afford' officers and agencies the ability to modify their work routines. Further, these modifications occur in conjunction with particular dimensions of body camera system's material agency. Through the performativity of video recording devices to move, see, hear, and record, officers report altering how they approach patrol work by displacing certain tasks onto their material associates, which allows them to better carry out their duties. Through the interoperability of the cloud storage systems, departments describe being able to reorganise critical information processing routines in support of criminal prosecutions. Through the objectivity of the digital files produced by body-worn camera systems, departments note effortlessly creating packets of events bearing the impression of truth and legitimacy with which they are able to more easily resolve citizen complaints. These findings underscore the importance of remaining attentive to the materiality of technology in policing and law enforcement research. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) are the leading cause of death in Latin America and the Caribbean (LAC) region as well as worldwide. Lifestyle, nutritional habits and the upsurge of obesity have contributed to the increase in the prevalence of CVDs in the region. The role of nuclear cardiology in the management of patients with CVDs is well established. Particularly, myocardial perfusion imaging is widely used in LAC countries and has been increasingly integrated into the healthcare systems in the region for the diagnosis of coronary artery disease, risk stratification and to guide patient management. In its role to support countries around the world to address their health needs through the peaceful applications of nuclear techniques, the International Atomic Energy Agency (IAEA) has provided assistance to the LAC region for the establishment and strengthening of the nuclear cardiology practice. To that extent, the IAEA provides support in building capacities of multidisciplinary teams of professionals, the provision of medical equipment and the promotion of communication and exchange of knowledge among the different stakeholders. In addition, the IAEA encourages the participation of nuclear medicine centers in international multi-center research studies. In this paper, we present some of the projects through which the IAEA has supported the LAC region, including regional technical cooperation projects and coordinated research projects related to cardiology within the current multimodality approach to cardiac imaging. [ABSTRACT FROM AUTHOR]

Objective: To determine the susceptibility of teeth to darken after bleaching with 35% hydrogen peroxide and 16% carbamide peroxide. Method and Materials: Thirty-eight premolars were covered with varnish and the mesiobuccal facets polished up to 0.04 [micro]m, leaving a flat surface. Thirty-six of these premolars were then randomly assigned to 3 groups and the shade of the polished surfaces recorded using a Vita shade guide set in a value disposition. According to the manufacturers' instructions, 12 samples were bleached with 35% hydrogen peroxide (in-office group) and 12 samples with 16% carbamide peroxide (at-home group). The 12 samples in the control group were not bleached. Two days later, the shades of the bleached teeth were recorded; all samples were immersed in silver nitrate 50% for 4 hours, rinsed, and fixed (using a dithioxamide solution) for 24 hours. Polished surfaces were cleaned and the samples' shade recorded and analyzed using ANOVA. The remaining 2 premolars were bleached the same as those in the test group and analyzed using atomic force microscopy. Results: The mean shade values were 6.2, 3.7, and 10.9 for in-office samples; 8.8, 1.7, and 6.1 for at-home samples; and 7.8 and 9.4 for the control group. After pigmentation, the at-home group had a lighter shade than the in-office group (P

Motivation Visualization of multiple genomic data generally requires the use of public or commercially hosted browsers. Flexible visualization of chromatin interaction data as genomic features and network components offer informative insights to gene expression. An open source application for visualizing HiC and chromatin conformation-based data as 2D-arcs accompanied by interactive network analyses is valuable. Results DNA Rchitect is a new tool created to visualize HiC and chromatin conformation-based contacts at high (Kb) and low (Mb) genomic resolutions. The user can upload their pre-filtered HiC experiment in bedpe format to the DNA Rchitect web app that we have hosted or to a version they themselves have deployed. Using DNA Rchitect, the uploaded data allows the user to visualize different interactions of their sample, perform simple network analyses, while also offering visualization of other genomic data types. The user can then download their results for additional network functionality offered in network based programs such as Cytoscape. Availability and implementation DNA Rchitect is freely available both as a web application written primarily in R available at http://shiny.immgen.org/DNARchitect/ and as an open source released under an MIT license at: https://github.com/alosdiallo/DNA_Rchitect. [ABSTRACT FROM AUTHOR]

Purpose: This study examines the long-term outcomes of paediatric Morquio (MPS IVA) patients undergoing cervical spine surgery and evaluates the factors that impacting this.Methods: A retrospective review was performed on all MPS IVA patients undergoing cervical spine surgery, since the introduction of standardised neuroradiological screening. The impact of preoperative neurological status, growth, genotype and radiological status on outcome is assessed, whilst long-term surgical, radiological and neurological outcomes are documented.Results: Twenty-six of the eighty-two MPS IVA patients (31%) reviewed underwent cervical spine surgery at a median age of 6.1 years (range, 1.45 to 15.24). Preoperatively, cord signal change was seen in 11 patients with 5 being myelopathic; however, 6 clinically manifesting patients had no overt cord signal change. Postoperatively, none of the 14 preoperatively clinically asymptomatic patients followed long term progressed neurologically during a median follow-up of 77.5 months (range = 18-161). Of the ten preoperatively clinically symptomatic patients who were followed up for the same duration, seven continued to deteriorate, two initially improved and one remained stable. Radiological follow-up performed for a median duration of 7 years (range = 0.5-16) has shown a degree of stenosis at the level immediately caudal to the termination of the graft in 76% of patients, though only one has become clinically symptomatic and required revision.Conclusions: Once clinically elicitable neurological signs become evident in patients with MPS IVA, they tend to progress despite surgical intervention. Referring clinicians should also not be falsely reassured by the lack of T2 spinal cord signal change but should consider surgical intervention in the face of new clinical symptomology or radiological signs of progressive canal stenosis or instability. [ABSTRACT FROM AUTHOR]

This work reports the effect of reduction temperature during the synthesis of PdAg catalysts through the polyol process and their evaluation in the ethanol electrooxidation reaction (EOR). The characterization was performed using Transmission Electron Microscopy (TEM) and X-Ray Diffraction (XRD). The electrochemical evaluation for the ethanol electrooxidation reaction was implemented in alkaline medium using chronoamperometry (CA) and cyclic voltammetry (CV). An important effect of the reduction temperature on electroactivity and catalytic stability was observed: both the maximum current density and the catalytic stability were higher in the catalyst synthesized at the highest temperature (135°C). This performance was associated with the extent of the interaction between Pd and Ag which was measured in terms of the structural expansion of Pd. [ABSTRACT FROM AUTHOR]

Alfalfa is a critical cash/rotation crop in the western region of the United States, where it is common to find crops affected by the alfalfa stem nematode (ASN) ( Ditylenchus dipsaci). Understanding the spread dynamics associated with this pest would allow growers to design better management programs and farming practices. This understanding is of particular importance given that there are no nematicides available against ASNs and control strategies largely rely on crop rotation to nonhost crops or by planting resistant varieties of alfalfa. In this paper, we present a basic host-parasite model that describes the spread of the ASN on alfalfa crops. With this discrete time model, we are able to portray a relationship between the length of crop rotation periods and the time at which the density of nematode-infested plants becomes larger than that of nematode-free ones in the postrotation alfalfa. The numerical results obtained are consistent with farming practice observations, suggesting that the model could play a role in the evaluation of management strategies. [ABSTRACT FROM AUTHOR]

Introduction: Dorsal root ganglia (DRG) are highly vulnerable to frataxin deficiency in Friedreich ataxia (FA), an autosomal recessive disease due to pathogenic homozygous guanine-adenine-adenine trinucleotide repeat expansions in intron 1 of the FXN gene (chromosome 9q21.11). An immunohistochemical and immunofluorescence study of DRG in 15 FA cases and 12 controls revealed that FA causes major primary changes in satellite cells and inflammatory destruction of neurons. A panel of antibodies was used to reveal the cytoplasm of satellite cells (glutamine synthetase, S100, metabotropic glutamate receptors 2/3, excitatory amino acid transporter 1, ATP-sensitive inward rectifier potassium channel 10, and cytosolic ferritin), gap junctions (connexin 43), basement membranes (laminin), mitochondria (ATP synthase subunit beta and frataxin), and monocytes (CD68 and IBA1). Results: Reaction product of the cytoplasmic markers and laminin confirmed proliferation of satellite cells and processes into multiple perineuronal layers and residual nodules. The formation of connexin 43-reactive gap junctions between satellite cells was strongly upregulated. Proliferating satellite cells in FA displayed many more frataxin- and ATP5B-reactive mitochondria than normal. Monocytes entered into the satellite cell layer, appeared to penetrate neuronal plasma membranes, and infiltrated residual nodules. Satellite cells and IBA1-reactive monocytes displayed upregulated ferritin biosynthesis, which was most likely due to leakage of iron from dying neurons. Conclusions: We conclude that FA differentially affects the key cellular elements of DRG, and postulate that the disease causes loss of bidirectional trophic support between satellite cells and neurons. [ABSTRACT FROM AUTHOR]

The purpose of this study is to assess how studying abroad impacts the development of intercultural competence and the moderating role of student’s personality. This research uses a pre-post design with a sample of 264 undergraduate students from four Colombian universities; it includes a group of students who participated in a one semester study-abroad program and a control group who did not travel. The average level of increase in intercultural competence for the students who went abroad was 0.511 standard deviations above the average of those who had not studied abroad. The results from hierarchical linear regression did not yield any evidence that supports the moderating effects of the personality factors on the relation between study abroad and intercultural competence. [ABSTRACT FROM AUTHOR]

It has been found that solar bursts exhibit one unexpected spectral component with fluxes increasing with frequency in the sub-THz range, which is distinct from the well-known microwave emission that peaks at a few to some tens of GHz. This component has been found to extend into the THz range of frequencies by recent 30 THz solar flare observations of impulsive bursts with flux intensities considerably higher than fluxes at sub-THz and microwaves frequencies. High-cadence solar observations at 30 THz (continuum) are therefore an important tool for the study of active regions and flaring events. We report the recent installation of a new 30 THz solar telescope in São Paulo, located at the top of one of the University's buildings. The instrument uses a Hale-type coelostat with two 20 cm diameter flat mirrors sending light to a 15 cm mirror Newtonian telescope. Radiation is directed to a microbolometer array camera that is kept at room temperature. Observations are usually obtained with $5~\mbox{frames}\,\mbox{s}^{-1}$ cadence. One 60 mm refractor has been added to observe $\mathrm{H}\upalpha$ images simultaneously. We describe our new telescopes and the new observatory examples of the first results obtained. [ABSTRACT FROM AUTHOR]

Friedreich ataxia (FA) is an autosomal recessive disease with a complex neurological phenotype, but the most common cause of death is heart failure. This study presents a systematic analysis of 15 fixed and 13 frozen archival autopsy tissues of FA hearts and 10 normal controls (8 frozen) by measurement of cardiomyocyte hypertrophy; tissue frataxin assay; X-ray fluorescence (XRF) of iron (Fe) and zinc (Zn) in polyethylene glycol-embedded samples of left and right ventricular walls (LVW, RVW) and ventricular septum (VS); metal quantification in bulk digests by inductively-coupled plasma optical emission spectrometry (ICP-OES); Fe histochemistry; and immunohistochemistry and immunofluorescence of cytosolic and mitochondrial ferritins and of the inflammatory markers CD68 and hepcidin. FA cardiomyocytes were significantly larger than normal and surrounded by fibrotic endomysium. Frataxin in LVW was reduced to less than 15 ng/g wet weight (normal 235.4±75.1 ng/g). All sections displayed characteristic Fe-reactive inclusions in cardiomyocytes, and XRF confirmed significant regional Fe accumulation in LVW and VS. In contrast, ICP-OES analysis of bulk extracts revealed normal total Fe levels in LVW, RVW, and VS. Cardiac Zn remained normal by XRF and assay of bulk digests. Cytosolic and mitochondrial ferritins exhibited extensive co-localization in cardiomyocytes, representing translational and transcriptional responses to Fe, respectively. Fe accumulation progressed from a few small granules to coarse aggregates in phagocytized cardiomyocytes. All cases met the “Dallas criteria” of myocarditis. Inflammatory cells contained CD68 and cytosolic ferritin, and most also expressed the Fe-regulatory hormone hepcidin. Inflammation is an important factor in the pathogenesis of FA cardiomyopathy but may be more evident in advanced stages of the disease. Hepcidin-induced failure of Fe export from macrophages is a likely contributory cause of damage to the heart in FA. Frataxin replacement and anti-inflammatory agents are potential therapies in FA cardiomyopathy. [ABSTRACT FROM AUTHOR]

Purpose: Eccentric exercise has been proposed as an alternate modality for chronic disease patients who cannot tolerate strenuous or vigorous intensity exercise. However, there is limited information regarding the biological benefits of this type of training compared to 'traditional' exercise. In this exploratory randomised clinical trial, we evaluated the feasibility and efficacy of eccentric exercise in the amelioration of markers of insulin resistance and inflammation. Methods: Ten participants (age 50.0 ± 15 years, BMI 31.3 ± 7.1 kg/m) with newly diagnosed T2DM and a sedentary lifestyle were randomly assigned to eccentric or concentric training performed during ten 30-min sessions of aerobic exercise over a 2-week period. Fasting blood samples were obtained pre- and 24 h post-intervention to determine insulin resistance (HOMA-IR, OGTT) and circulating cytokine (IL-6, TNF-α) concentrations. Results: Despite the reduced heart rate ( p = 0.008), the eccentric training group performed more work over the ten training sessions ( p = 0.016) with no differences in the participant's perceived exertion ( p = 0.69). No significant between- or within-group changes were observed for OGTT, HOMA-IR or markers of inflammation ( p > 0.05). However, there was a modest but consistent amelioration of OGTT, IL-6 and TNF-α that was been observed in the eccentric training group but not in the concentric training group. Conclusion: Preliminary findings from this exploratory study would tend to suggest that short-term eccentric exercise is well tolerated in previously sedentary T2DM patients and that the trend towards reductions in circulating insulin resistance and inflammatory markers requires validation in an adequately powered clinical trial conducted over a longer duration. [ABSTRACT FROM AUTHOR]