358 research outputs found
The Jabal Akhdar Dome in the Oman Mountains : evolution of a dynamic fracture system
Acknowledgments: This study was carried out within the framework of DGMK (German Society for Petroleum and Coal Science and Technology) research project 718 “Mineral Vein Dynamics Modelling,” which is funded by the companies ExxonMobil Production Deutschland GmbH, GDF SUEZ E&P Deutschland GmbH, RWE Dea AG and Wintershall Holding GmbH, within the basic research program of the WEG Wirtschaftsverband Erdo¨l- und Erdgasgewinnung e.V. We thank the companies for their financial support and their permission to publish these results. The German University of Technology in Oman (GU-Tech) is acknowledged for its logistic support. We gratefully acknowledge the reviewers Andrea Billi and Jean-Paul Breton, whose constructive reviews greatly improved the manuscriptPeer reviewedPreprin
Quantum Rod Emission Coupled to Plasmonic Lattice Resonances: A Collective Directional Source of Polarized Light
We demonstrate that an array of optical antennas may render a thin layer of
randomly oriented semiconductor nanocrystals into an enhanced and highly
directional source of polarized light. The array sustains collective plasmonic
lattice resonances which are in spectral overlap with the emission of the
nanocrystals over narrow angular regions. Consequently, different photon
energies of visible light are enhanced and beamed into definite directions.Comment: 4 pages, 3 figure
Coupling Bright and Dark Plasmonic Lattice Resonances
We demonstrate the coupling of bright and dark Surface Lattice Resonances
(SLRs), which are collective Fano resonances in 2D plasmonic crystals. As a
result of this coupling, a frequency stop-gap in the dispersion relation of
SLRs is observed. The different field symmetries of the low and high frequency
SLR bands lead to pronounced differences in their coupling to free space
radiation. Standing waves of very narrow spectral width compared to localized
surface plasmon resonances are formed at the high frequency band edge, while
subradiant damping onsets at the low frequency band edge leading the resonance
into darkness. We introduce a coupled oscillator analog to the plasmonic
crystal, which serves to elucidate the physics of the coupled plasmonic
resonances and to estimate very high quality factors (Q>700) for SLRs, which
are the highest known for any 2D plasmonic crystal.Comment: 13 pages (in preprint), 4 figures, 1 tabl
Azimuthally polarized cathodoluminescence from InP nanowires
We determine the angle and polarization dependent emission from 1.75 µm and 2.50 µm long InPnanowires by using cathodoluminescencepolarimetry. We excite the vertical wires using a 5 keV electron beam, and find that the 880 nm bandgap emission shows azimuthally polarized rings, with the number of rings depending on the wire height. The data agree well with a model in which spontaneous emission from the wire emitted into the far field interferes with emission reflected off the substrate. From the model, the depth range from which the emission is generated is found to be up to 400 nm below the top surface of the wires, well beyond the extent of the primary electron cloud. This enables a probe of the carrier diffusion length in the InPnanowires. 2015 AIP Publishing LLC</p
Directional Emission from Leaky and Guided Modes in GaAs Nanowires Measured by Cathodoluminescence
We measure the polarization-resolved angular emission distribution from thin and thick GaAs nanowires (diameters ∼110 and ∼180 nm) with cathodoluminescence polarimetry. The nanowires, which horizontally rest on a thin carbon film, are excited by a 5 keV electron beam and emit band gap luminescence at a central wavelength of 870 nm. The emission can couple to different waveguide modes that propagate along the wire, are dependent on the wire diameter, and determine the directionality and polarization of the emission. Although each measured nanowire can support different modes, the polarized emission is dominated by the TM01 waveguide mode in all cases, independently of wire diameter. When exciting the nanowires close to the end facets, the thin and thick wires exhibit opposite directional emission. The emission from thin nanowires is dominated by a leaky TM01 mode that leads to emission toward the opposite end facet (emission to the right when exciting the left-side edge). For the thick wires, however, the TM01 mode is guided but also lossy due to absorption in the substrate. In such a case, the wires emit toward the excited end facet (to the left when exciting the left-side edge). The emission directionality switches for nanowire diameters in the range of 145–170 nm. We show that the measurements agree well with both a simple 1D current model and numerical simulations. The high spatial resolution of angle- and polarization-resolved cathodoluminescence spectroscopy provides detailed insight into the nanoscale emission and propagation of light in semiconductor nanowires.</p
Identification of viral infections in the prostate and evaluation of their association with cancer
<p>Abstract</p> <p>Background</p> <p>Several viruses with known oncogenic potential infect prostate tissue, among these are the polyomaviruses BKV, JCV, and SV40; human papillomaviruses (HPVs), and human cytomegalovirus (HCMV) infections. Recently, the Xenotropic Murine Leukemia Virus-related gammaretrovirus (XMRV) was identified in prostate tissue with a high prevalence observed in prostate cancer (PC) patients homozygous for the glutamine variant of the RNASEL protein (462Q/Q). Association studies with the R462Q allele and non-XMRV viruses have not been reported. We assessed associations between prostate cancer, prostate viral infections, and the RNASEL 462Q allele in Mexican cancer patients and controls.</p> <p>Methods</p> <p>130 subjects (55 prostate cancer cases and 75 controls) were enrolled in the study. DNA and RNA isolated from prostate tissues were screened for the presence of viral genomes. Genotyping of the RNASEL R462Q variant was performed by Taqman method.</p> <p>Results</p> <p>R/R, R/Q, and Q/Q frequencies for R462Q were 0.62, 0.38, and 0.0 for PC cases and 0.69, 0.24, and 0.07 for controls, respectively. HPV sequences were detected in 11 (20.0%) cases and 4 (5.3%) controls. XMRV and HCMV infections were detected in one and six control samples, respectively. The risk of PC was significantly increased (Odds Ratio = 3.98; 95% CI: 1.17-13.56, p = 0.027) by infection of the prostatic tissue with HPV. BKV, JCV, and SV40 sequences were not detected in any of the tissue samples examined.</p> <p>Conclusions</p> <p>We report a positive association between PC and HPV infection. The 462Q/Q RNASEL genotype was not represented in our PC cases; thus, its interaction with prostate viral infections and cancer could not be evaluated.</p
New Ultra-minimally Invasive Surgical Treatment for Benign Prostatic Hyperplasia: A Systematic Review and Analysis of Comparative Outcomes
Context: Benign prostatic hyperplasia (BPH) associated with lower urinary tract symptoms (LUTS) is diagnosed in up to 80% of men during their lifetime. Several novel ultra-minimally invasive surgical treatments (uMISTs) for BPH/benign prostatic obstruction (BPO) have become available over the past 5 yr. Objective: To evaluate the perioperative and functional outcomes of recently introduced uMISTs for BPH/BPO, including Urolift, Rezūm, temporary implantable nitinol device, prostatic artery embolization (PAE), and intraprostatic injection. Evidence acquisition: A systematic literature search was conducted in December 2020 using Medline (via PubMed), Embase (via Ovid), Scopus, and Web of Science (registered on PROSPERO as CRD42021225014). The search strategy used PICO criteria and article selection was conducted in accordance with the PRISMA guidelines. The risk of bias and the quality of the articles included were assessed. A dedicated data extraction form was used to collect the data of interest. Pooled and cumulative analyses were performed to compare perioperative and functional outcomes between study groups. A random-effects model using the DerSimonian and Laird method was used to evaluate heterogeneity. Stata version 15.0 software was used for all statistical analyses. Evidence synthesis: The initial electronic search identified 3978 papers, of which 48 ultimately met the inclusion criteria and were included in the analysis. Pooled analysis revealed a uMIST benefit in terms of International Prostate Symptom Score (IPSS; −9.81 points, 95% confidence interval [CI] −11.37 to −8.25 at 1 mo; −13.13 points, 95% CI −14.98 to −11.64 at 12 mo), maximum flow rate (from +3.66 ml/s, 95% CI 2.8–4.5 to +4.14 ml/s, 95% CI 0.72–7.56 at 12 mo), and postvoid residual volume (−10.10 ml, 95% CI −27.90 to 7.71 at 12 mo). No negative impact was observed on scores for the International Index of Erectile Function-5, Male Sexual Health Questionnaire-Ejaculatory Dysfunction bother and function scales (overall postintervention change in pooled median score of 1.88, 95% CI 1.34–2.42 at the start of follow-up; and 1.04, 95% CI 0.28–1.8 after 1 yr), or the IPSS-Quality of Life questionnaire. Conclusions: Novel uMISTs can yield fast and effective relief of LUTS without affecting patient quality of life. Only Rezūm, UroLift, and PAE had a minimal impact on patients’ sexual function with respect to baseline, especially regarding preservation of ejaculation. Patient summary: We reviewed outcomes for recently introduced ultra-minimally invasive surgical treatments for patients with lower urinary tract symptoms caused by benign prostate enlargement or obstruction. The evidence suggests that these novel techniques are beneficial in terms of controlling symptoms while preserving sexual function. Take Home Message: Novel ultra-minimally invasive treatments can yield fast and effective relief of lower urinary tract symptoms without affecting a patient's quality of life
Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015
SummaryBackground The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Funding Bill & Melinda Gates Foundation
Proposal of a Nutritional Quality Index (NQI) to Evaluate the Nutritional Supplementation of Sportspeople
Background:
Numerous supplements are used by sportspeople. They are not always appropriate for the individual or the sports activity and may do more harm than good. Vitamin and mineral supplements are unnecessary if the energy intake is sufficient to maintain body weight and derives from a diet with an adequate variety of foods. The study objectives were to evaluate the main nutrients used as supplements in sports and to propose a nutritional quality index (NQI) that enables sportspeople to optimize their use of supplements and detect and remedy possible nutritional deficits.
Material and Methods:
A nutritional study was performed in 485 sportspeople recruited from Centros Andaluces de Medicina del Deporte, (CAMD). All completed socio-demographic, food frequency, and lifestyle questionnaires. The nutritional quality of their diet and need for supplementation were evaluated by scoring their dietary intake with and without supplementation, yielding two NQI scores (scales of 0-21 points) for each participant.
Results:
A superior mean NQI score was obtained when the supplements taken by participants were not included (16. 28 (SD of 3.52)) than when they were included (15.47 (SD: 3.08)), attributable to an excessive intake of some nutrients through supplementation.
Conclusions:
These results indicate that sportspeople with a varied and balanced diet do not need supplements, which appear to offer no performance benefits and may pose a health risk.The authors are grateful to the Junta de Andalucía, Spain (Research Group AGR-255“Nutrition. Diet and Risk Assessment”), a collaboration agreement with the Andalusian Centres of Sports Medicine (Junta de Andalucía) and the FPU program of the Spanish Ministry of Education and Science. Study participants were recruited through the project “Nutritional and diet assessment methodologies applied to the Andalusian sportsperson in Andalusian Sports centres”, Research project FMD2010SC0071 of the Junta de Andalucía
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