During the design of nonimaging Fresnel lenses, the reflectance losses at the refracting surfaces should be taken into account because, depending on the parameters of each prism, semiacceptance angle ...θin and output angle θout, these losses can decrease the total efficiency of the lens. On this subject, an analysis and comparison between a Fresnel lens composed only of refractive prisms and others with total internal reflection (TIR) prisms are presented and, using this information, a design method of hybrid Fresnel lenses composed of refractive and TIR prisms is proposed to reduce reflectance losses from the surface. The work presents the radiance profile and transmittance for a Fresnel lens of each type, to compare its advantages and disadvantages providing an alternative for the design and construction of nonimaging Fresnel lenses according to optical devices requirements.
A green method for producing pristine porous ZnO nanoparticles with narrow particle size distribution is reported. This method consists in synthesizing ZnO2 nanopowders via a hydrothermal route using ...cheap and non-toxic reagents, and its subsequent thermal decomposition at low temperature under a non-protective atmosphere (air). The morphology, structural and optical properties of the obtained porous ZnO nanoparticles were studied by means of powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and nitrogen adsorption–desorption measurements. It was found that after thermal decomposition of the ZnO2 powders, pristine ZnO nanoparticles are obtained. These particles are round-shaped with narrow size distribution. A further analysis of the obtained ZnO nanoparticles reveals that they are hierarchical self-assemblies of primary ZnO particles. The agglomeration of these primary particles at the very early stage of the thermal decomposition of ZnO2 powders provides to the resulting ZnO nanoparticles a porous nature. The possibility of using the synthesized porous ZnO nanoparticles as photocatalysts has been evaluated on the degradation of rhodamine B dye.
•A green synthesis method for obtaining porous ZnO nanoparticles is reported.•The obtained ZnO nanoparticles have narrow particle size distribution.•This method allows obtaining pristine ZnO nanoparticles avoiding unintentional doping.•A growth mechanism for the obtained porous ZnO nanoparticles is proposed.
The thymus is the anatomical site where T cells undergo a complex process of differentiation, proliferation, selection, and elimination of autorreactive cells which involves molecular signals in ...different intrathymic environment. However, the immunological functions of the thymus can be compromised upon exposure to different infections, affecting thymocyte populations. In this work, we investigated the impact of malaria parasites on the thymus by using C57BL/6 mice infected with Plasmodium berghei ANKA and Plasmodium yoelii 17XL; these lethal infection models represent the most severe complications, cerebral malaria, and anemia respectively. Data showed a reduction in the thymic weight and cellularity involving different T cell maturation stages, mainly CD4
CD8
and CD4
CD8
thymocytes, as well as an increased presence of apoptotic cells, leading to significant thymic cortex reduction. Thymus atrophy showed no association with elevated serum cytokines levels, although increased glucocorticoid levels did. The severity of thymic damage in both models reached the same extend although it occurs at different stages of infection, showing that thymic atrophy does not depend on parasitemia level but on the specific host-parasite interaction.
The aim of this study was to assess the scientific output of Spanish universities that offer a bachelor's degree in dentistry through the use of various bibliometric indicators.
A total of 21 ...universities offered a bachelor's degree in dentistry in academic year 2016-2017. The search for papers published by authors associated with these institutions was carried out using the selection of journals listed in the Journal Citation Reports (JCR) and the Web of Knowledge database for the period 1986-2017. On the basis of these data, we determined the output, the h-, g- and hg-indexes, the most productive authors, international collaborations, and the most relevant journals.
Public universities obtained better results than private universities. The University of Valencia was ranked first, followed by the Complutense University of Madrid and the University of Granada. The most productive author was José Vicente Bagán, but the author with the highest h-index was Mariano Sanz and Manuel Toledado. The universities with the greatest output and highest citation rates had more international collaborations. The most developed fields in Spanish universities were Oral surgery, Oral medicine and Dental materials. The universities had different models of production. At universities such as Barcelona or Valencia, the production was focused on very few departments and authors. At the other extreme, the University of Granada had various sources of research and authors, which meant that its output and citation rate could increase more.
University faculties must provide suitable academic and research training, and therefore must be assessed using objective criteria and bibliometric tools. Although the number of university schools and faculties that teach dentistry has increased, and particularly the number of private universities, there is no correlation between their quality and output and the number of places offered on their courses.
We present the results of the first IceCube search for dark matter annihilation in the center of the Earth. Weakly interacting massive particles (WIMPs), candidates for dark matter, can scatter off ...nuclei inside the Earth and fall below its escape velocity. Over time the captured WIMPs will be accumulated and may eventually self-annihilate. Among the annihilation products only neutrinos can escape from the center of the Earth. Large-scale neutrino telescopes, such as the cubic kilometer IceCube Neutrino Observatory located at the South Pole, can be used to search for such neutrino fluxes. Data from 327 days of detector livetime during 2011/2012 were analyzed. No excess beyond the expected background from atmospheric neutrinos was detected. The derived upper limits on the annihilation rate of WIMPs in the Earth and the resulting muon flux are an order of magnitude stronger than the limits of the last analysis performed with data from IceCube's predecessor AMANDA. The limits can be translated in terms of a spin-independent WIMP-nucleon cross section. For a WIMP mass of 50 GeV this analysis results in the most restrictive limits achieved with IceCube data.
The mechanical behavior of an aged pipeline, affected by localized and generalized corrosion defects, is investigated using the finite element method. A sample of pipeline steel was aged artificially ...via an isothermal process (which represents the natural aging transformations), to obtain the mechanical characteristics. In real scenarios, oil and gas pipelines undergo deterioration owing to both aging and corrosion defects.Therefore, this research studies the assessment of failure pressure by combining these two types of deterioration using the finite element method. To calibrate the methodology proposed for estimating the pipeline failure pressure,data from real-scale burst tests published by the Pipeline Research Council International (PRCI) was used. Following the simulations, the initial failure region for each type of defect was determined and analyzed. Similarly, the estimated values of pipeline failure pressure were compared to assess the results obtained through finite element analysis, considering the changes in mechanical characteristics caused by the artificialartificial aging of the steel. In addition, these results were compared with those of certain well-known semiempirical models. Finally, for the different types of corrosion defects investigated in this study, the effects of volumetric loss on the estimation of pipeline failure pressure using finite elements are discussed. The main conclusion of this study is that failure pressure can be estimated more accurately by considering both corrosion defects characteristics and variations in the steel properties caused by aging.
•Material specific reference stress determination for finite element analysis.•Finite element analysis assessment of three distinct corrosion defect geometries.•2D and 3D burst pressure models performance due to corrosion and aging effects.•Burst pressure capacity loss calculation for artificially aged API 5L Gr. B pipeline steel.•Influence of volumetric material loss from corrosion defects on failure pressure.
We sought to compare post-discharge outcomes and healthcare utilization between English-speaking non-Hispanic White (NHW), English-speaking Hispanic/Latinx (ESHL), and Spanish-speaking ...Hispanic/Latinx (SSHL) survivors of traumatic injury.OBJECTIVEWe sought to compare post-discharge outcomes and healthcare utilization between English-speaking non-Hispanic White (NHW), English-speaking Hispanic/Latinx (ESHL), and Spanish-speaking Hispanic/Latinx (SSHL) survivors of traumatic injury.While there is evidence of racial and ethnic disparities in healthcare utilization and post-discharge outcomes after injury, the role of English language proficiency in these disparities remains unclear.BACKGROUNDWhile there is evidence of racial and ethnic disparities in healthcare utilization and post-discharge outcomes after injury, the role of English language proficiency in these disparities remains unclear.Moderate to severely injured adults from three level-1 trauma centers completed an interview in English or Spanish between 6-12 months post-injury to assess physical health-related quality of life (SF-12-PCS), return to work, and post-discharge healthcare utilization. The language used in the interview was used as a proxy for English-language proficiency, and participants were categorized as either NHW (reference), ESHL, or SSHL. Multivariable regression models estimated independent associations between language and race/ethnicity with SF-12-PCS, return to work, and post-discharge healthcare utilization outcomes.METHODSModerate to severely injured adults from three level-1 trauma centers completed an interview in English or Spanish between 6-12 months post-injury to assess physical health-related quality of life (SF-12-PCS), return to work, and post-discharge healthcare utilization. The language used in the interview was used as a proxy for English-language proficiency, and participants were categorized as either NHW (reference), ESHL, or SSHL. Multivariable regression models estimated independent associations between language and race/ethnicity with SF-12-PCS, return to work, and post-discharge healthcare utilization outcomes.3,304 injury survivors were followed: 2,977 (90%) NHW, 203 (6%) ESHL, and 124 (4%) SSHL. In adjusted analyses, no significant differences were observed between ESHL and NHW injury survivors for any outcomes at 6-12 months post-injury. However, SSHL injury survivors exhibited a lower mean SF-12-PCS (41.6 vs. 38.5), -3.07 (95% CI=-5.47, -0.66; P=0.012), decreased odds of returning to work (OR=0.47; CI=0.27 to 0.81; P=0.007), and were less likely to engage in non-injury related outpatient visits, such as primary care visits (OR=0.45; 95% CI 0.28, 0.73; P=0.001), compared to NHW patients.RESULTS3,304 injury survivors were followed: 2,977 (90%) NHW, 203 (6%) ESHL, and 124 (4%) SSHL. In adjusted analyses, no significant differences were observed between ESHL and NHW injury survivors for any outcomes at 6-12 months post-injury. However, SSHL injury survivors exhibited a lower mean SF-12-PCS (41.6 vs. 38.5), -3.07 (95% CI=-5.47, -0.66; P=0.012), decreased odds of returning to work (OR=0.47; CI=0.27 to 0.81; P=0.007), and were less likely to engage in non-injury related outpatient visits, such as primary care visits (OR=0.45; 95% CI 0.28, 0.73; P=0.001), compared to NHW patients.Hispanic/Latinx injury survivors have worse post-discharge outcomes and lower non-injury-related healthcare utilization than NHW if they have limited English-language proficiency. Addressing LEP-related barriers to care could help mitigate outcome and healthcare utilization disparities among Hispanic/Latinx injury survivors.CONCLUSIONHispanic/Latinx injury survivors have worse post-discharge outcomes and lower non-injury-related healthcare utilization than NHW if they have limited English-language proficiency. Addressing LEP-related barriers to care could help mitigate outcome and healthcare utilization disparities among Hispanic/Latinx injury survivors.
Taming the terminological tempest in invasion science Soto, Ismael; Balzani, Paride; Carneiro, Laís ...
Biological reviews of the Cambridge Philosophical Society,
August 2024, Volume:
99, Issue:
4
Journal Article
Peer reviewed
Open access
ABSTRACT
Standardised terminology in science is important for clarity of interpretation and communication. In invasion science – a dynamic and rapidly evolving discipline – the proliferation of ...technical terminology has lacked a standardised framework for its development. The result is a convoluted and inconsistent usage of terminology, with various discrepancies in descriptions of damage and interventions. A standardised framework is therefore needed for a clear, universally applicable, and consistent terminology to promote more effective communication across researchers, stakeholders, and policymakers. Inconsistencies in terminology stem from the exponential increase in scientific publications on the patterns and processes of biological invasions authored by experts from various disciplines and countries since the 1990s, as well as publications by legislators and policymakers focusing on practical applications, regulations, and management of resources. Aligning and standardising terminology across stakeholders remains a challenge in invasion science. Here, we review and evaluate the multiple terms used in invasion science (e.g. ‘non‐native’, ‘alien’, ‘invasive’ or ‘invader’, ‘exotic’, ‘non‐indigenous’, ‘naturalised’, ‘pest’) to propose a more simplified and standardised terminology. The streamlined framework we propose and translate into 28 other languages is based on the terms (i) ‘non‐native’, denoting species transported beyond their natural biogeographic range, (ii) ‘established non‐native’, i.e. those non‐native species that have established self‐sustaining populations in their new location(s) in the wild, and (iii) ‘invasive non‐native’ – populations of established non‐native species that have recently spread or are spreading rapidly in their invaded range actively or passively with or without human mediation. We also highlight the importance of conceptualising ‘spread’ for classifying invasiveness and ‘impact’ for management. Finally, we propose a protocol for classifying populations based on (i) dispersal mechanism, (ii) species origin, (iii) population status, and (iv) impact. Collectively and without introducing new terminology, the framework that we present aims to facilitate effective communication and collaboration in invasion science and management of non‐native species.
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