6,812 research outputs found
On the Evaluation of the Mechanical Behaviour of Structural Glass Elements
Glass can be considered to be a high-technology engineering material with a
multifunctional potential for structural applications. However, the conventional approach to the use
of glass is often based only on its properties of transparency and isolation. It is thus highly
appropriate and necessary to study the mechanical behaviour of this material and to develop
adequate methods and models leading to its characterisation. It is evident that the great potential of
growth for structural glass applications is an important opportunity of development for the glass
industry and the building/construction sectors. The work presented in this paper is a reflection of
this conclusion. The authors shortly present the state-of-the-art on the application of glass as a
structural element in building and construction, and refer to other potential fields of application and
available glass materials. The experimental procedures and methods adopted in three-point bending
tests performed on 500 × 100 [mm2] float, laminated and tempered glass specimens with
thicknesses between 4 and 19 mm are thoroughly described. The authors evaluated the mechanical
strength and stiffness of glass for structural applications. This work contributes to a deeper
knowledge of the properties of this material
Evaluation of the Phytochemical Content and Antibacterial and Antioxidant Activity of Lasia spinosa in Sri Lanka
The usage and exploration of novel drugs and dietary supplements have been accelerated due to the emergence of multidrug resistance which causes by inappropriate use of antibiotics. Natural fruits and vegetables have recognised as preferable sources for natural antioxidants against free radicals and as an antimicrobial agent. Lasia spinosa has been acknowledged as a natural source with antibacterial, antioxidant, cytotoxic, anticestodal and anticarcinogenic activities, where it natively grows in Sri Lanka. Due to its properties, L. spinosa has been used in culinary and indigenous medicine for a long time. On the account, this particular study was carried out to evaluate the phytochemical components, their contribution to total antioxidant activity and the antibacterial activity in L. spinosa cultivated in Sri Lanka. The whole plant; leaves, stem, rhizome and roots were collected from the local market and evaluated. Phytochemicals were extracted using methanol as the solvent. The antibacterial potential of L. spinosa was screened against Staphylococcus aureus and Escherichia coli by the Kirby-Bauer disc diffusion method. Folin-ciocalteu method and aluminium chloride colourimetric method was used to assess the total phenolic content (TPC) and total flavonoid content (TFC) separately while 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 2,20-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assay were carried out to evaluate the antioxidant activities. L. spinosa roots and rhizome had the highest antibacterial activity against E.coli and S. aureus, respectively. Sample concentration of 5 mg/mL was selected for phytochemical and antioxidant assays as that concentration showed the broad-spectrum activity. Highest TPC and TFC were recorded from L. spinosa rhizome (54.1 mgGAE/mL) and stem (130 mgRE/mL), respectively. Roots showed the highest DPPH (78.44%) and ABTS (80%) activity. TPC values showed positive correlations with DPPH and ABTS scavenging activities (r=0.576 and r+0.722, p>0.05 respectively). TFC values showed a positive correlation with DPPH (r=0.576, p>0.05) and a negative correlation with ABTS (r= -0.497). Hence a better correlation was observed between TPC with DPPH and ABTS than TFC which indicate that TPC would be the possible contributor for antioxidant activity. Results from this experiment concluded that the L. spinosa root possessed the highest antioxidant and antibacterial activity over leaves, stem and rhizome which may confirm its efficacy towards drug development.Keywords: Lasia spinosa, Antioxidants, Antibacterial activity, Phytochemical
Diel feeding activity and intensity in the European eel Anguilla anguilla (L.) during an annual cycle in a Cantabrian stream
Diel and seasonal shifts in the feeding activity and intensity of a riverine stock of European eels, Anguilla anguilla (L.), were assessed in the Río LLorín, a right-side tributary of the Río Esva drainage (northwestern Spain). No consistent diel cycles were detected in either season (eels feed with similar intensity in the day and at night), but increased feeding activity was evidenced during the warmer months relative to weaker but still significant activity in winter. Heterogeneity in both feeding activity and intensity may stem from the high rates of secondary production in the form of benthic food available for eels, and mild temperatures all year round
A Nationwide Cross-Sectional Study
This study aims to compare adequate fruit and vegetable (F&V) intake between immigrants and natives in Portugal, and to analyse factors associated with consumption of F&V among immigrants. Data from a population based cross-sectional study (2014) was used. The final sample comprised 17,410 participants (≥20 years old), of whom 7.4% were immigrants. Chi-squared tests and logistic regression models were conducted to investigate the association between adequate F&V intake, sociodemographic, anthropometric, and lifestyle characteristics. Adequate F&V intake was more prevalent among immigrants (21.1% (95% CI: 19.0⁻23.4)) than natives (18.5% (95% CI: 17.9⁻19.1)), (p = 0.000). Association between migrant status and adequate F&V intake was only evident for men: immigrants were less likely to achieve an adequate F&V intake (OR = 0.67, 95% CI = 0.66⁻0.68) when compared to Portuguese. Among immigrants, being female, older, with a higher education, and living in a low urbanisation area increased the odds of having F&V consumption closer to the recommendations. Adjusting for other factors, length of residence appears as a risk factor (15 or more years vs. 0⁻9 years: OR = 0.52, 95% CI = 0.50⁻0.53), (p = 0.000) for adequate F&V intake. Policies aiming to promote adequate F&V consumption should consider both populations groups, and gender-based strategies should address proper sociodemographic, anthropometric, and lifestyle determinants.publishersversionpublishe
Homogeneous metallicities and radial velocities for Galactic globular clusters. II. New CaT metallicities for 28 distant and reddened globular clusters
Although the globular clusters in the Milky Way have been studied for a long
time, a significant fraction of them lack homogeneous metallicity and radial
velocity measurements. In an earlier paper we presented the first part of a
project to obtain metallicities and radial velocities of Galactic globular
clusters from multiobject spectroscopy of their member stars using the ESO Very
Large Telescope. In this paper we add metallicities and radial velocities for a
new sample of 28 globular clusters, including in particular globular clusters
in the MW halo and the Galactic bulge. Together with our previous results, this
study brings the number of globular clusters with homogeneous measurements to
\% of those listed in the W. Harris' catalogue. As in our previous
work, we have used the CaII triplet lines to derive metallicities and radial
velocities. For most of the clusters in this study, this is the first analysis
based on spectroscopy of individual member stars. The metallicities derived
from the CaII triplet are then compared to the results of our parallel study
based on spectral fitting in the optical region and the implications for
different calibrations of the CaII triplet line strengths are discussed. We
also comment on some interesting clusters and investigate the presence of an
abundance spread in the globular clusters here. A hint of a possible intrinsic
spread is found for NGC 6256, which therefore appears to be a good candidate
for further study.Comment: 13 pages, 9 figures, accepted for publication in Astronomy and
Astrophysic
Building Bio-Districts or Eco-Regions: Participative Processes Supported by Focal Groups
Over the years, rural areas have faced a number of problems and difficulties, such as an
increase in the average age of the population, desertification, loss of employment and the abandon‐
ment of rural and agricultural activities, which have led to the emergence of new initiatives aimed
at revitalizing these territories from a social, economic and environmental perspective, such as the
successful Bio‐districts or Eco‐regions (e.g., Bio‐district of Cilento). Understanding and establishing
a proper framework for each territory based on agroecology and participatory methodologies is still
a challenge. In this sense, based on the analysis of two European examples—Cilento, Italy and São
Pedro do Sul, Portugal—we described each of the building processes and defined a set of drivers
that might constitute guiding principles to serve as a basis for the creation of Bio‐districts or Eco‐
regions. The drivers’ matrix identified was discussed in three focus groups carried out in Portugal
in 2020. Such drivers included a technical and environmental component (the quality of the envi‐
ronment and landscape, the food system and the implementation of organic farming and agroeco‐
logical practices), a social and economic component (valorization of the farmers, products and ter‐
ritories and a set of different stakeholders—farmers, consumers, schools, tourism entities and res‐
taurants, local authorities) and a political component (the governance model). Most participants
agreed that the recognition of a Bio‐district or Eco‐region should be informal, bottom‐up, with farm‐
ers as the main pillar, with a fair and representative participation, namely family farmers.info:eu-repo/semantics/publishedVersio
Dynamical amplification of magnetoresistances and Hall currents up to the THz regime
Spin-orbit-related effects offer a highly promising route for reading and
writing information in magnetic units of future devices. These phenomena rely
not only on the static magnetization orientation but also on its dynamics to
achieve fast switchings that can reach the THz range. In this work, we consider
Co/Pt and Fe/W bilayers to show that accounting for the phase difference
between different processes is crucial to the correct description of the
dynamical currents. By tuning each system towards its ferromagnetic resonance,
we reveal that dynamical spin Hall angles can non-trivially change sign and be
boosted by over 500%, reaching giant values. We demonstrate that charge and
spin pumping mechanisms can greatly magnify or dwindle the currents flowing
through the system, influencing all kinds of magnetoresistive and Hall effects,
thus impacting also dc and second harmonic experimental measurements.Comment: 19 pages, 4 figures, Supplementary Informatio
NeuroPrime: a Pythonic framework for the priming of brain states in self-regulation protocols
Due to the recent pandemic and a general boom
in technology, we are facing more and more threats of isolation,
depression, fear, overload of information, between others. In
turn, these affect our Self, psychologically and physically.
Therefore, new tools are required to assist the regulation of this
unregulated Self to a more personalized, optimal and healthy
Self. As such, we developed a Pythonic open-source humancomputer
framework for assisted priming of subjects to
“optimally” self-regulate their Neurofeedback (NF) with
external stimulation, like guided mindfulness. For this, we did a
three-part study in which: 1) we defined the foundations of the
framework and its design for priming subjects to self-regulate
their NF, 2) developed an open-source version of the framework
in Python, NeuroPrime, for utility, expandability and
reusability, and 3) we tested the framework in neurofeedback
priming versus no-priming conditions. NeuroPrime is a
research toolbox developed for the simple and fast integration
of advanced online closed-loop applications. More specifically,
it was validated and tuned for the research of priming brain
states in an EEG neurofeedback setup. In this paper, we will
explain the key aspects of the priming framework, the
NeuroPrime software developed, the design decisions and
demonstrate/validate the use of our toolbox by presenting use
cases of priming brain states during a neurofeedback setup.MIT -Massachusetts Institute of Technology(PD/BD/114033/2015
Changes in Assortative Matching and Inequality in Income: Evidence for the UK
The extent to which like‐with‐like marry is important for inequality as well as for the outcomes of children who result from the union. In this paper, we present evidence on changes in assortative mating and its implications for household inequality in the UK. Our approach contrasts with others in the literature in that it is consistent with an underlying model of the marriage market. We argue that a key advantage of this approach is that it creates a direct connection between changes in assortativeness in marriage and changes in the value of marriage for the various possible matches by education group. Our empirical results do not show a clear direction of change in assortativeness in the UK between the birth cohorts of 1945–54 and 1965–74. We find that changes in assortativeness pushed income inequality up slightly, but that the strong changes in education attainment across the two cohorts contributed to scale down inequality
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