380 research outputs found

    Analysis of pedestrians’ road crossing behavior, in social groups

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    A significant percentage of pedestrians walk in social groups (friends, families, or acquaintances who walk together). Although patterns generated by social interactions among group members have been shown to affect crowd dynamics, studies on the effect of social interactions at different crossing phases under low pedestrian density are limited. This study aims to comprehensively examine the influence of size and sex composition on pedestrians’ behaviors when walking alone and with friends in different phases before, during, and after the road crossing. For this, experiences were carried out with controlled small groups of friends (varying size and sex composition) at three unsignalized crosswalks with low pedestrian density. The average speed and distance between the young pedestrians in six segments of the trajectories (two in each phase), extracted from video recordings, were analyzed with linear mixed models. Results show that pedestrians reduce their speed when approaching the curb, they accelerate while on the crosswalk, and reduce again when they reach the other side. In all phases, the average speed of the groups was lower than the single pedestrians, and the females’ groups walked slower than the males, except during the crossing, where no sex-related differences were found. On the contrary, before the crossing, the distance increased and decreased from the second segment in the crosswalk. The smallest distance was observed between the female groups and dyads. These findings have relevant implications for research on pedestrian behavior, helping to better understand the complexity of pedestrian dynamics and improve pedestrian safety.FCT -Fundação para a Ciência e a Tecnologia(LA/P/0112/2020

    Maize and Risk of Cancers of the Oral Cavity, Pharynx, and Esophagus in Northeastern Italy

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    The relationship between maize consumption and risk of cancer of the upper digestive tract was investigated in 107 patients with oral cancer, 107 with pharyngeal cancer, 68 with esophageal cancer, and 505 hospital controls who permanently resided in Pordenone Province in the northeastern part of Italy. The analysis was restricted to males. The population of this province has a high incidence of these neoplasms and shows particularly elevated levels of alcohol and tobacco use, in addition to high maize consumption. Highly significant associations with frequent intake of maize emerged for oral cancer, pharyngeal cancer, and esophageal cancer (odds ratios = 3.3, 3.2, and 2.8, respectively). The risk elevation could not be explained in terms of differences in education, occupation, tobacco use, or consumption of fresh fruits and vegetables. The unfavorable effect of maize on risk of cancer of the upper digestive tract, however, was evident only in those individuals who reported heavy drinking (i.e., ≥42 alcoholic drinks/wk). The present findings are likely to be related to the fact that maize can cause deficiencies of various micronutrients (chiefly, niacin and riboflavin) and agree with previous observations from Africa, the People's Republic of China, the United States, and Italy. [J Natl Cancer Inst 82:1407-1411, 1990

    Cancer and Non-Cancer Controls in Studies on the Effect of Tobacco and Alcohol Consumption

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    A comparison of risk estimates using controls with other cancers versus controls with acute diseases unrelated to tobacco and alcohol consumption in the study of the effect of these two factors has been performed using data on tumours of the oral cavity and pharynx from an ongoing case-control surveillance programme in Northeastern Italy. Similar results were obtained using either type of controls: as compared to never smokers, moderate smokers (≤14 cigarettes/day) showed age-and sex-adjusted odds ratio (OR)=5.2 (95% confidence interval (CI): 2.9-9.2) when using cancer controls and 5.8 (95% CI: 3.3-10.1) when using non-cancer controls. Similarly, those who had smoked for 40 years or longer showed ORs of 7.4(95% CI: 4.0-13.6) and 8.8 (95% CI: 4.9-15.6), respectively, using cancer and non-cancer controls: For moderate drinkers of alcoholic beverages (21-34 drinks/week) and heavy drinkers (≥84 drinks/ week) the ORs, as compared to individuals who drank <21 drinks/week, were 1.9 (95%CI: 1.0-3.6) and 2.2 (95% CI: 1.2-4.0) and 10.6(95% CI: 5.5-20.6) and 11.4(95% CI: 6.0-21.4) using cancer and non-cancer controls, respectively. The same comparability of ORs for tobacco- and alcohol-related variables using either type of controls was observed when separate analyses of the two sexes were performed. The close similarity between cancer and non-cancer controls in studies on tabacco- and alcohol-related risks may be exploited when the choice of other types of controls would increase the costs and the feasibility of the study, and thus hamper its statistical power. Moreover, this investigation provides some reassurance about the validity of risk estimates using carefully selected groups of hospital control

    Climate services and insurance: scaling climate smart agriculture

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    One of the main challenges of climate-smart agriculture (CSA) is finding ways to promote the adoption at scale (Editor’s note: 'scaling', 'at scale' or 'to scale' are used throughout this article to mean ‘scaling-out’) of CSA practices and technologies. Climate services and insurance can constitute a tool to scale CSA by providing an enabling environment that can support the adoption of CSA practices while protecting against the impacts of climate extremes. By using a definition of climate services which includes the production, translation, transfer, and use of climate knowledge and information in climate-informed decision-making and climatesmart policy and planning, this paper aims to discuss how climate services and insurance can bring CSA to scale. Three case studies are presented. It is recognised that understanding the knowledge networks through which information flows, and affects the use of climate information, is critical for promoting CSA at scale

    Estado del Arte en Cambio Climático, Agricultura y Seguridad Alimentaria de la República Dominicana

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    La República Dominicana es un país con un alto nivel de exposición y vulnerabilidad a eventos climáticos extremos a nivel mundial; es por esto que el Ministerio de Agricultura (MA) en colaboración con el Programa de Investigación CGIAR en Cambio Climático, Agricultura y Seguridad Alimentaria (CCAFS, por sus siglas en inglés) en América Latina y con apoyo del Consejo Agropecuario Centroamericano (CAC) presentan el “Estado del Arte en Cambio Climático, Agricultura y Seguridad Alimentaria de la República Dominicana”, que incluye el marco gubernamental y actores involucrados en torno a esta temática. En el documento se evidencia como los efectos del cambio climático han afectado el campo dominicano en gran parte de sus cultivos y como el gobierno ha venido enfatizando esfuerzos para disminuir la vulnerabilidad de la población y aumentar su resiliencia mediante políticas públicas y acciones integrales

    Valence change of praseodymium in Pr0.5Ca0.5CoO3 investigated by x-ray absorption spectroscopy

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    X-ray absorption spectroscopy measurements in Pr0.5Ca0.5CoO3 were performed at the Pr M4,5, Pr L3, and Ca L2,3 absorption edges as a function of temperature below 300 K. Ca spectra show no changes down to 10 K while a noticeable thermally dependent evolution takes place at the Pr edges across the metal-insulator transition. Spectral changes are analyzed by different methods, including multiple scattering simulations, which provide quantitative details on an electron loss at Pr 4f orbitals. We conclude that in the insulating phase a fraction [15(+5)%] of Pr3+ undergoes a further oxidation to adopt a hybridized configuration composed of an admixture of atomic-like 4f1 states (Pr4+) and f- symmetry states on the O 2p valence band (Pr3+L states) indicative of a strong 4f- 2p interaction.Comment: 19 pages (.doc), 4 figures, Phys. Rev. B, in pres

    Fluorescent in vivo imaging of reactive oxygen species and redox potential in plants

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    Reactive oxygen species (ROS) are by-products of aerobic metabolism, and excessive production can result in oxidative stress and cell damage. In addition, ROS function as cellular messengers, working as redox regulators in a multitude of biological processes. Understanding ROS signalling and stress responses requires methods for precise imaging and quantification to monitor local, subcellular and global ROS dynamics with high selectivity, sensitivity and spatiotemporal resolution. In this review, we summarize the present knowledge for in vivo plant ROS imaging and detection, using both chemical probes and fluorescent protein-based biosensors. Certain characteristics of plant tissues, for example high background autofluorescence in photosynthetic organs and the multitude of endogenous antioxidants, can interfere with ROS and redox potential detection, making imaging extra challenging. Novel methods and techniques to measure in vivo plant ROS and redox changes with better selectivity, accuracy, and spatiotemporal resolution are therefore desirable to fully acknowledge the remarkably complex plant ROS signalling networksThis work was funded by a grant from the Spanish Ministry of Economy and Competitiveness ( AGL2014–53771-R ). Alfonso Blázquez-Castro acknowledges funding under the Marie Skłodowska-Curie Action COFUND 2015 (EU project 713366 – InterTalentum

    Variation in contrast-associated acute kidney injury prophylaxis for percutaneous coronary intervention: Insights from the Veterans Affairs Clinical Assessment, Reporting, and Tracking (CART) program

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    BACKGROUND: Contrast-Associated Acute Kidney Injury (CA-AKI) is a serious complication associated with percutaneous coronary intervention (PCI). Patients with chronic kidney disease (CKD) have an elevated risk for developing this complication. Although CA-AKI prophylactic measures are available, the supporting literature is variable and inconsistent for periprocedural hydration and N-acetylcysteine (NAC), but is stronger for contrast minimization. METHODS: We assessed the prevalence and variability of CA-AKI prophylaxis among CKD patients undergoing PCI between October 2007 and September 2015 in any cardiac catheterization laboratory in the VA Healthcare System. Prophylaxis included periprocedural hydration with normal saline or sodium bicarbonate, NAC, and contrast minimization (contrast volume to glomerular filtration rate ratio ≤ 3). Multivariable hierarchical logistic regression models quantified site-specific prophylaxis variability. As secondary analyses, we also assessed CA-AKI prophylaxis measures in all PCI patients regardless of kidney function, periprocedural hydration in patients with comorbid CHF, and temporal trends in CA-AKI prophylaxis. RESULTS: From 2007 to 2015, 15,729 patients with CKD underwent PCI. 6928 (44.0%) received periprocedural hydration (practice-level median rate 45.3%, interquartile range (IQR) 35.5-56.7), 5107 (32.5%) received NAC (practice-level median rate 28.3%, IQR 22.8-36.9), and 4656 (36.0%) received contrast minimization (practice-level median rate 34.5, IQR 22.6-53.9). After adjustment for patient characteristics, there was significant site variability with a median odds ratio (MOR) of 1.80 (CI 1.56-2.08) for periprocedural hydration, 1.95 (CI 1.66-2.29) for periprocedural hydration or NAC, and 2.68 (CI 2.23-3.15) for contrast minimization. These trends were similar among all patients (with and without CKD) undergoing PCI. Among patients with comorbid CHF (n = 5893), 2629 (44.6%) received periprocedural hydration, and overall had less variability in hydration (MOR of 1.56 (CI 1.38-1.76)) compared to patients without comorbid CHF (1.89 (CI 1.65-2.18)). Temporal trend analysis showed a significant and clinically relevant decrease in NAC use (64.1% of cases in 2008 (N = 1059), 6.2% of cases in 2015 (N = 128, p = \u3c 0.0001)) and no significant change in contrast-minimization (p = 0.3907). CONCLUSIONS: Among patients with CKD undergoing PCI, there was low utilization and significant site-level variability for periprocedural hydration and NAC independent of patient-specific risk. This low utilization and high variability, however, was also present for contrast minimization, a well-established measure. These findings suggest that a standardized approach to CA-AKI prophylaxis, along with continued development of the evidence base, is needed

    Face-to-Face and Tele-Consults: A Study of the Effects on Diagnostic Activity and Patient Demand in Primary Healthcare

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    Primary healthcare services have changed from face-to-face to tele-consults during the two COVID-19 years. We examined trends before and during the COVID-19 pandemic years based on groups of professionals, patient ages, and the associations with the diagnostic registry. We analyzed proportions for both periods, and ratios of the type of consults in 2017-2019 and 2020-2021 were calculated. The COVID-19 period was examined using monthly linear time trends. The results showed that consults in 2020-2021 increased by 24%. General practitioners saw significant falls in face-to-face consults compared with 2017-2019 (ratio 0.44; 95% CI: 0.44 to 0.45), but the increase was not proportional across age groups; patients aged 15-44 years had 45.8% more tele-consults, and those aged >74 years had 18.2% more. Trends in linear regression models of face-to-face consults with general practitioners and monthly diagnostic activity were positive, while the tele-consult trend was inverse to the trend of the diagnostic registry and face-to-face consults. Tele-consults did not resolve the increased demand for primary healthcare services caused by COVID-19. General practitioners, nurses and primary healthcare professionals require better-adapted tele-consult tools for an effective diagnostic registry to maintain equity of access and answer older patients' needs and priorities in primary healthcare
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