353 research outputs found
Airborne geophysical survey of part of Anglesey, North Wales
An airborne magnetic, electromagnetic and radiometric survey was
carried out over part of Anglesey, North Wales. In this report
of the survey, an outline of the geology, with brief descriptions
of survey techniques, data reduction and presentation are given.
General descriptions are presented of four areas of distinct
magnetic character, with interpretations of the more prominent
anomalies such as those associated with the Carmel Head Thrust,
with Tertiary dykes and with various hornfels bodies.
Possible extensions of known ultrabasic bodies and areas where
other such potentially mineralised bodies may be concealed have
been shown, in particular near Llandyfrydog (SH 44 85)and near
the coast south of Valley (SH 31 76).
The electromagnetic survey data are not described in detail
because radio transmissions caused strong anomalies unrelated to
the geology and masked most of the real anomalies. Those
anomalies which remained were due largely to man-made objects.
Examination of the radiometric traces showed no indication of
uranium mineralisation or any other substantial concentration of
radioactive elements
A magnetotelluric survey southwards from the Bodmin granite
This report describes a reconnaissance MagnetoTelluric (MT) survey carried out in early 1993 as part of the TMOS mapping programme of the Plymouth sheet in SW England. An 8 site survey, along a N-S profile extending from near the coast onto the Bodmin granite was conducted during an 8 day field programme. The purpose of the survey was to investigate
the relevance of the MT method to mapping the configuration of the geological units at depth.
The MT method provides geological information by modelling the subsurface resistivity distribution, usually along a profile. In order to provide valid structural assessments the data modelling must take into account the observed data characteristics. The present initial report provides information on the survey, the measurements undertaken and the data obtained. The subsurface structure across the profile is assessed using geoelectric strike directions, one-dimensional (l-D) inversion and two-dimensional (2-D) inversion
Diagonally Neighbour Transitive Codes and Frequency Permutation Arrays
Constant composition codes have been proposed as suitable coding schemes to
solve the narrow band and impulse noise problems associated with powerline
communication. In particular, a certain class of constant composition codes
called frequency permutation arrays have been suggested as ideal, in some
sense, for these purposes. In this paper we characterise a family of neighbour
transitive codes in Hamming graphs in which frequency permutation arrays play a
central rode. We also classify all the permutation codes generated by groups in
this family
Timescales of IP(3)-evoked Ca(2+) spikes emerge from Ca(2+) puffs only at the cellular level
The behavior of biological systems is determined by the properties of their component molecules, but the interactions are usually too complex to understand fully how molecular behavior generates cellular behavior. Ca(2+) signaling by inositol trisphosphate receptors (IP(3)R) offers an opportunity to understand this relationship because the cellular behavior is defined largely by Ca(2+)-mediated interactions between IP(3)R. Ca(2+) released by a cluster of IP(3)R (giving a local Ca(2+) puff) diffuses and ignites the behavior of neighboring clusters (to give repetitive global Ca(2+) spikes). We use total internal reflection fluorescence microscopy of two mammalian cell lines to define the temporal relationships between Ca(2+) puffs (interpuff intervals, IPI) and Ca(2+) spikes (interspike intervals) evoked by flash photolysis of caged IP(3). We find that IPI are much shorter than interspike intervals, that puff activity is stochastic with a recovery time that is much shorter than the refractory period of the cell, and that IPI are not periodic. We conclude that Ca(2+) spikes do not arise from oscillatory dynamics of IP(3)R clusters, but that repetitive Ca(2+) spiking with its longer timescales is an emergent property of the dynamics of the whole cluster array
Improving nutrition with agricultural biodiversity
This guide describes the process and procedures for collecting important information required to assess local farming systems and agrobiodiversity, household food consumption norms and the nutritional status of vulnerable groups within a given population using specific indicators. Additionally, this guide provides a framework for practical implementation of a holistic program that focuses on creating a customized intervention based on community-specific data. The manual strives to combine perspectives from the following models and approaches: 1. Farming Systems Model (FAO/WB) 2. Agroecological Model (NAFRI, FAO) 3. Indigenous Food Culture Documentation (CINE/IDRC/FAO) 4. Measuring Nutritional Functional Diversity (Columbia EI) 5. Positive Deviance Model (The Positive Deviance Initiative) 6. FANTA Nutritional Assessment Guides (USAID) 7. Food Security and Livelihoods Model (ACF International) 8. Ethnobotanical Documentation: A User’s Model (ICH/UNESCO) The development of this manual also could not have been possible without the guidance of previously published manuals by the World Health Organization (WHO), the World Food Programme (WFP) and the Centre for Indigenous Peoples’ Nutrition and Environment CINE. This manual recommends a 7 phase process to approach communities of focus holistically and with a trajectory of long-term improvement
Improving nutrition with agricultural biodiversity
This guide describes the process and procedures for collecting important information required to assess local farming systems and agrobiodiversity, household food consumption norms and the nutritional status of vulnerable groups within a given population using specific indicators. Additionally, this guide provides a framework for practical implementation of a holistic program that focuses on creating a customized intervention based on community-specific data. The manual strives to combine perspectives from the following models and approaches: 1. Farming Systems Model (FAO/WB) 2. Agroecological Model (NAFRI, FAO) 3. Indigenous Food Culture Documentation (CINE/IDRC/FAO) 4. Measuring Nutritional Functional Diversity (Columbia EI) 5. Positive Deviance Model (The Positive Deviance Initiative) 6. FANTA Nutritional Assessment Guides (USAID) 7. Food Security and Livelihoods Model (ACF International) 8. Ethnobotanical Documentation: A User’s Model (ICH/UNESCO) The development of this manual also could not have been possible without the guidance of previously published manuals by the World Health Organization (WHO), the World Food Programme (WFP) and the Centre for Indigenous Peoples’ Nutrition and Environment CINE. This manual recommends a 7 phase process to approach communities of focus holistically and with a trajectory of long-term improvement
Aspects of Two-Photon Physics at Linear e+e- Colliders
We discuss various reactions at future e+e- and gamma-gamma colliders
involving real (beamstrahlung or backscattered laser) or quasi--real
(bremsstrahlung) photons in the initial state and hadrons in the final state.
The production of two central jets with large pT is described in some detail;
we give distributions for the rapidity and pT of the jets as well as the
di--jet invariant mass, and discuss the relative importance of various initial
state configurations and the uncertainties in our predictions. We also present
results for `mono--jet' production where one jet goes down a beam pipe, for the
production of charm, bottom and top quarks, and for single production of W and
Z bosons. Where appropriate, the two--photon processes are compared with
annihilation reactions leading to similar final states. We also argue that the
behaviour of the total inelastic gamma-gamma cross section at high energies
will probably have little impact on the severity of background problems caused
by soft and semi--hard (`minijet') two--photon reactions. We find very large
differences in cross sections for all two--photon processes between existing
designs for future e+e- colliders, due to the different beamstrahlung spectra;
in particular, both designs with >1 events per bunch crossing exist.Comment: 51 pages, 13 figures(not included
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National or population level interventions addressing the social determinants of mental health – an umbrella review
Background
Social circumstances in which people live and work impact the population’s mental health. We aimed to synthesise evidence identifying effective interventions and policies that influence the social determinants of mental health at national or scaled population level. We searched five databases (Cochrane Library, Global Health, MEDLINE, EMBASE and PsycINFO) between Jan 1st 2000 and July 23rd 2019 to identify systematic reviews of population-level interventions or policies addressing a recognised social determinant of mental health and collected mental health outcomes. There were no restrictions on country, sub-population or age. A narrative overview of results is provided. Quality assessment was conducted using Assessment of Multiple Systematic Reviews (AMSTAR 2). This study was registered on PROSPERO (CRD42019140198).
Results
We identified 20 reviews for inclusion. Most reviews were of low or critically low quality. Primary studies were mostly observational and from higher income settings. Higher quality evidence indicates more generous welfare benefits may reduce socioeconomic inequalities in mental health outcomes. Lower quality evidence suggests unemployment insurance, warm housing interventions, neighbourhood renewal, paid parental leave, gender equality policies, community-based parenting programmes, and less restrictive migration policies are associated with improved mental health outcomes. Low quality evidence suggests restriction of access to lethal means and multi-component suicide prevention programmes are associated with reduced suicide risk.
Conclusion
This umbrella review has identified a small and overall low-quality evidence base for population level interventions addressing the social determinants of mental health. There are significant gaps in the evidence base for key policy areas, which limit ability of national policymakers to understand how to effectively improve population mental health
Balloon Measurements of Cosmic Ray Muon Spectra in the Atmosphere along with those of Primary Protons and Helium Nuclei over Mid-Latitude
We report here the measurements of the energy spectra of atmospheric muons
and of the cosmic ray primary proton and helium nuclei in a single experiment.
These were carried out using the MASS superconducting spectrometer in a balloon
flight experiment in 1991. The relevance of these results to the atmospheric
neutrino anomaly is emphasized. In particular, this approach allows
uncertainties caused by the level of solar modulation, the geomagnetic cut-off
of the primaries and possible experimental systematics to be decoupled in the
comparison of calculated fluxes of muons to measured muon fluxes. The muon
observations cover the momentum and depth ranges of 0.3-40 GeV/c and 5-886
g/cmsquared, respectively. The proton and helium primary measurements cover the
rigidity range from 3 to 100 GV, in which both the solar modulation and the
geomagnetic cut-off affect the energy spectra at low energies.Comment: 31 pages, including 17 figures, simplified apparatus figure, to
appear in Phys. Rev.
Very-high energy gamma-ray astronomy: A 23-year success story in high-energy astroparticle physics
Very-high energy (VHE) gamma quanta contribute only a minuscule fraction -
below one per million - to the flux of cosmic rays. Nevertheless, being neutral
particles they are currently the best "messengers" of processes from the
relativistic/ultra-relativistic Universe because they can be extrapolated back
to their origin. The window of VHE gamma rays was opened only in 1989 by the
Whipple collaboration, reporting the observation of TeV gamma rays from the
Crab nebula. After a slow start, this new field of research is now rapidly
expanding with the discovery of more than 150 VHE gamma-ray emitting sources.
Progress is intimately related with the steady improvement of detectors and
rapidly increasing computing power. We give an overview of the early attempts
before and around 1989 and the progress after the pioneering work of the
Whipple collaboration. The main focus of this article is on the development of
experimental techniques for Earth-bound gamma-ray detectors; consequently, more
emphasis is given to those experiments that made an initial breakthrough rather
than to the successors which often had and have a similar (sometimes even
higher) scientific output as the pioneering experiments. The considered energy
threshold is about 30 GeV. At lower energies, observations can presently only
be performed with balloon or satellite-borne detectors. Irrespective of the
stormy experimental progress, the success story could not have been called a
success story without a broad scientific output. Therefore we conclude this
article with a summary of the scientific rationales and main results achieved
over the last two decades.Comment: 45 pages, 38 figures, review prepared for EPJ-H special issue "Cosmic
rays, gamma rays and neutrinos: A survey of 100 years of research
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