8,745 research outputs found
Tell me who your friends are?! The mediating role of friends use in cannabis abuse
Objective: To evaluate the relationship between onset age of cannabis use and cannabis abuse testing the mediating role of the number of friends using cannabis with a sample of Portuguese cannabis users. Comparing men and women regarding these relationships. Method: A sample of 529 Portuguese cannabis users, composed of 276 men and 244 women, aged from 14 to 21 years, completed a sociodemographic questionnaire, the Cannabis Abuse Screening Test and four questions related to cannabis use. Data were analyzed using the PROCESS macro in SPSS version 26.0. Results: The onset age of cannabis use was negatively related to the number of friends using cannabis, while the number of friends using cannabis showed a positive relationship with cannabis abuse. As predicted, the number of friends using cannabis seems to have a mediating role in the relationship between the onset age of cannabis use and cannabis abuse since the indirect effect was found to be significant. The pattern of the relationships among the variables observed was found to be similar both for the male and women' samples. However, males reported higher cannabis abuse than females. Conclusion: Results highlight the mediating role of the friends' using cannabis in the relationship between the onset age of cannabis use and users' abuse. Results highlight the importance of early intervention to cannabis use. Particularly, the pattern of the relationships observed among the studied variables emphasized the need to monitor and peer training intervention or the promotion of social skills.info:eu-repo/semantics/acceptedVersio
TORCH: A Cherenkov Based Time-of-Flight Detector
TORCH is a novel high-precision time-of-flight detector suitable for large area applications and
covering the momentum range up to 10 GeV/c. The concept uses Cherenkov photons produced
in a fused silica radiator which are propagated to focussing optics coupled to fast photodetectors.
For this purpose, custom MCP-PMTs are being produced in collaboration with industrial partners.
The development is divided into three phases. Phase 1 addresses the lifetime requirements for
TORCH, Phase 2 will customize the MCP-PMT granularity and Phase 3 will deliver prototypes
that meet the TORCH requirements. Phase 1 devices have been successfully delivered and initial
tests show stable gain performance for integrated anode current >5 C/cm2
and a single photon
time resolution of ≤ 30 ps. Initial simulations indicate the single photon timing resolution of the
TORCH detector will be ∼70 ps
First record of a tropical shallow water barnacle Tetraclita sp. (Cirripedia: Tetraclitoidea) from the middle Neogene of the Canary Islands
This paper describes the first record of the intertidal, tropical tetraclitoid barnacle Tetraclita sp. cf. T. stalactifera (Lamarck, 1818) from the middle Neogene of the Canary Islands. The barnacles were recovered as isolated plates from a bioclastic volcanic agglomerate. Associated fauna in- cludes patellid and neritid gastropods, and an oyster bank, which confirm a shallow-water litoral setting. Living Tetraclita stalactifera is recorded from tropical waters of the America, South Africa and the Arabian Sea; it is first recorded as fossil from Plio-Pleistocene of Curaçao (Caribbean Sea, Venezuela)
Understanding herbivore-plant-soil feedbacks to improve grazing management on Mediterranean mountain grasslands
The surface of many European mountain grasslands is decreasing due to global change and extensive grazing stands out as a key tool for their conservation. Sound knowledge of grassland ecosystem functioning and its feedback processes is required to implement sustainable grazing management. This study aimed to understand the effect of different grazing intensities on herbivore-plant-soil feedbacks in Mediterranean mountain grasslands. We estimated spatial distribution of sheep grazing intensity using GPS technology in order to assess the effect of grazing pressure on vegetation and soil properties measured throughout the study area. Our results showed that grazing intensity ranged from 0.06 to 2.85 livestock units / ha, corresponding to a gradient of pasture utilisation rates varying from 2.38% to 45.60% of annual productivity from pasture. Increasing grazing pressure was associated with smaller relative cover and species richness of non-leguminous forbs, while the opposite trends were observed for graminoids. Forage had a greater concentration of N and smaller C:N ratio in more heavily grazed areas. Increasing grazing intensity was also associated with higher values of total soil N, NO3-, NH4+, soil organic carbon, microbial biomass C and activity of ß-glucosidase. Higher litter quality was the main factor explaining greater content of soil organic matter, which favoured both soil microbes and plant productivity. Grazing induced changes in the plant community triggered positive hervibore-plant-soil feedbacks, as they ultimately improved forage quality and productivity, which significantly influenced the pasture preference of free-ranging domestic grazers. Our work showed that grazing management aiming pasture utilisation rates of around 45% is critical in sustaining positive herbivore-plant-soil feedbacks and preserving or enhancing the whole ecosystem functioning in the Mediterranean mountain grasslands studied. © 2021 The Author
PCV86 Long-Term Cost-Effectiveness Analysis of Ticagrelor in Patients with Acute Coronary Syndrome (ACS) from A Mexican Public and Private Health Care Perspective Based on Data from the Plato Trial
A finite element approach to model high-velocity impact on thin woven GFRP plates
A finite element model to predict the ballistic behaviour of woven GFRP laminates is presented. This finite element model incorporates a new constitutive model based on a continuum damage mechanics approach able to predict the performance of these laminates under high-velocity impacts. The material parameters of the model are identified from the literature and original experiments conducted in this work. The predictive capability of the model is verified against experimental impact tests. Finally, the model is used to analyse the influence of laminate thickness on different energy absorption mechanisms at velocities near the ballistic limit. This analysis allows for the determination of the principal deformation and failure mechanisms governing the perforation process.L. Alonso, S.K.GarcÃa Castillo and C.Navarro are indebted to the project 'Acción Estratégica en Materiales Compuestos y Análisis Numérico simplificado de Estructuras y protecciones ligeras sometidas a impacto balÃstico' (2010/00309/002) of the University Carlos III of Madrid for the financial support of this work. F. MartÃnez-Hergueta acknowledges support from PECRE1819_02 from the Scottish Research Partnership in Engineering. D. Garcia-Gonzalez acknowledges support from the Talent Attraction grant (CM 2018 - 2018-T2/IND-9992) from the Comunidad de Madrid
U B V R I Photometry of Stellar Structures throughout the Disk of the Barred Galaxy NGC 3367
We report new detailed surface U, B, V, R, and I photometry of 81 stellar
structures in the disk of the barred galaxy NGC 3367. The images show many
different structures indicating that star formation is going on in the most
part of the disk. NGC 3367 is known to have a very high concentration of
molecular gas distribution in the central regions of the galaxy and bipolar
synchrotron emission from the nucleus with two lobes (at 6 kpc) forming a
triple structure similar to a radio galaxy. We have determined the U, B, V, R,
and I magnitudes and U - B, B - V, U - V, and V - I colors for the central
region (nucleus), a region which includes supernovae 2003 AA, and 79 star
associations throughout NGC 3367. Estimation of ages of star associations is
very difficult due to several factors, among them: filling factor, metallicity,
spatial distribution of each structure and the fact that we estimated the
magnitudes with a circular aperture of 16 pixels in diameter, equivalent to
kpc. However, if the colors derived for NGC 3367 were similar to
the colors expected of star clusters with theoretical evolutionary star tracks
developed for the LMC and had a similar metallicity, NGC 3367 show 51 percent
of the observed structures with age type SWB I (few tens of Myrs), with seven
sources outside the bright surface brightness visible disk of NGC 3367.Comment: Accepted for publication (abr 2007) in The Astronomical Journal (July
2007 issue
Phenotypes of non-alcoholic fatty liver disease (NAFLD) and all-cause mortality: Unsupervised machine learning analysis of NHANES III
Objectives: Non-alcoholic fatty liver disease (NAFLD) is a non-communicable disease with a rising prevalence worldwide and with large burden for patients and health systems. To date, the presence of unique phenotypes in patients with NAFLD has not been studied, and their identification could inform precision medicine and public health with pragmatic implications in personalised management and care for patients with NAFLD. Design: Cross-sectional and prospective (up to 31 December 2019) analysis of National Health and Nutrition Examination Survey III (1988–1994). Primary and secondary outcomes measures: NAFLD diagnosis was based on liver ultrasound. The following predictors informed an unsupervised machine learning algorithm (k-means): body mass index, waist circumference, systolic blood pressure (SBP), plasma glucose, total cholesterol, triglycerides, liver enzymes alanine aminotransferase, aspartate aminotransferase and gamma glutamyl transferase. We summarised (means) and compared the predictors across clusters. We used Cox proportional hazard models to quantify the all-cause mortality risk associated with each cluster. Results: 1652 patients with NAFLD (mean age 47.2 years and 51.5% women) were grouped into 3 clusters: anthro-SBP-glucose (6.36%; highest levels of anthropometrics, SBP and glucose), lipid-liver (10.35%; highest levels of lipid and liver enzymes) and average (83.29%; predictors at average levels). Compared with the average phenotype, the anthro-SBP-glucose phenotype had higher all-cause mortality risk (aHR=2.88; 95% CI: 2.26 to 3.67); the lipid-liver phenotype was not associated with higher all-cause mortality risk (aHR=1.11; 95% CI: 0.86 to 1.42). Conclusions: There is heterogeneity in patients with NAFLD, whom can be divided into three phenotypes with different mortality risk. These phenotypes could guide specific interventions and management plans, thus advancing precision medicine and public health for patients with NAFLD
Modelling high velocity impact on thin woven composite plates: A non-dimensional theoretical approach
Novel incorporation of red-stage haematococcus pluvialis wet paste as a colourant and enhancer of the organoleptic and functional properties of filloas â€
Haematococcus pluvialis Flotow is a microalga used as a nutraceutical, due to its high content
in bioactive compounds, mainly carotenoids, in which astaxanthin stands out [1]. Furthermore, H. plu-
vialis has shown a high antioxidant potential, and combined with its intense red colour, this microalga
could have dual functionality: as a colourant and a bioactive ingredient [ 2]. The process to obtain this
ingredient involves several transformation steps—namely, lyophilisation and saponification—raising
the costs to develop and obtain free astaxanthin, which paradoxically presents greater instability
and solubility than its esterified counterpart [ 3]. Thus, this study provides an alternative approach
for the application of red, astaxanthin-rich, H. pluvialis wet paste as a partial substitute for wheat
flour (7% and 13% w/w) in the preparation of filloas (Galician pancakes), a typical dessert from the
northwestern region of the Iberian Peninsula. To evaluate its power as a natural pigment, the stability
of colour over time (3, 6, and 9 days) was measured, and the results were compared with those of a
commercial colourant. At the same time, its physicochemical properties such as the microbiological
profile were measured to determine its functionality as a food preservative. As a result, redness
stability (a*) of 8% higher than that of the commercial colourant was obtained for the maximum
concentration of H. pluvialis analysed. The texture showed a significant response (p < 0.02), improving
its properties as the concentration of the microalga increased, which showed a tenacity of 3.23 N and
extensibility of 15.10 mm during the first 6 days, i.e., a 52% and 19% improvement, respectively, in
relation to the control group. In turn, an enrichment of carotenoids, fatty acids, and phenolic com-
pounds, in combination with a potential moderator of microbiological degradation by this unicellular
organism, gives added value to this food matrix.This research was funded by project ED431 2020/06 (Galician Competitive Research Groups
Xunta de Galicia). This study was supported by project EQC2018-005011-P (Ministry of Science,
Innovation and Universities, Spain). All these programmes are co-funded by FEDER (EU). The
authors are also grateful to Foundation for Science and Technology (FCT, Portugal) for financial
support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); to FCT for S. Heleno
(CEECIND/03040/2017) and L. Barros contracts through the individual and institutional scientific
employment programme contract, respectively. This article is based upon work from the Sample
Preparation Study Group and Network, supported by the Division of Analytical Chemistry of the
European Chemical Societyinfo:eu-repo/semantics/publishedVersio
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