2,714 research outputs found

    A review of the contribution of thermal mass to thermal comfort in rammed earth structures

    Get PDF
    Rammed earth is a construction material which has been used to build thermally-comfortable structures in many regions around the world for thousands of years. Despite this heritage, rammed earth is currently considered to be unsuitable for construction by many green-building guidelines due to its low thermal resistance, a property deemed to be necessary if a structure is to reduce its heating and cooling demand. This paper introduces thermal comfort and relates it to thermal resistance and thermal mass. A review of previous work which has investigated thermal comfort in rammed earth structures is then presented. Techniques used to adapt the designs of traditional rammed earth structures to suit their prevalent climate are then briefly discussed and compared to modern construction practices in similar regions to suggest methods by which the thermal comfort and sustainability of modern structures can be improved

    Neonatal abstinence syndrome.

    Get PDF
    A 12 month review of infants admitted with neonatal abstinence syndrome to a neonatal intensive care unit was undertaken. The relationship of maternal drug abuse to symptoms, the effectiveness of pharmacologic agents in controlling symptoms and the length of inpatient stay were investigated. A retrospective review of maternal and infant records was performed. Those infants with a serial Finnegan score greater than 8 were treated. Pharmacologic treatment was oral morphine sulphate (0.2 mg 4-6 hourly), phenobarbitone (3-7 mgs/kg/day), or combination of the above. 43 infants were admitted to the hospital during the year. The average maternal age was 24.6 years, (18-34 years). Drug use volunteered by the mothers was methadone alone in 6 cases, methadone and benzodiazepines in 14, methadone and heroin and benzodiazepines in 7, methadone and heroin in 10, heroin alone in 2, and other multiple drug use including oral morphine sulphate, dothiepin and cannabis in 4. Average gestational age was 40.3 (35-42 weeks). The average birthweight was 2.81 kgs (1.89-3.91 kgs). Time to onset of withdrawal symptoms was 2.8 (1-13) days. The duration of pharmacologic treatment (oral morphine sulphate and/or phenobarbitone) was 21.8 (1-62) days. The total hospital stay for the 43 infants was 1,011 days. This study confirms that polydrug abuse is the commonest type of drug abuse in Dublin. The duration of withdrawal symptoms is loosely related to drug type, but increasing duration of symptoms is noted for infants exposed to benzodiazepines. Our experience would favour the use of morphine sulphate to treat pure opiate withdrawal symptoms. Over the 12-month period, there was an average occupancy of 3 beds per day in the paediatric department

    Population history from the Neolithic to present on the Mediterranean island of Sardinia: an ancient DNA perspective

    No full text
    Recent ancient DNA studies of western Eurasia have revealed a dynamic history of admixture, with evidence for major migrations during the Neolithic and Bronze Age. The population of the Mediterranean island of Sardinia has been notable in these studies –} Neolithic individuals from mainland Europe cluster more closely with Sardinian individuals than with all other present-day Europeans. The current model to explain this result is that Sardinia received an initial influx of Neolithic ancestry and then remained relatively isolated from expansions in the later Neolithic and Bronze Age that took place in continental Europe. To test this model, we generated genome-wide capture data (approximately 1.2 million variants) for 43 ancient Sardinian individuals spanning the Neolithic through the Bronze Age, including individuals from Sardinia{’}s Nuragic culture, which is known for the construction of numerous large stone towers throughout the island. We analyze these new samples in the context of previously generated genome-wide ancient DNA data from 972 ancient individuals across western Eurasia and whole-genome sequence data from approximately 1,500 modern individuals from Sardinia. The ancient Sardinian individuals show a strong affinity to western Mediterranean Neolithic populations and we infer a high degree of genetic continuity on the island from the Neolithic (around fifth millennium BCE) through the Nuragic period (second millennium BCE). In particular, during the Bronze Age in Sardinia, we do not find significant levels of the {“}Steppe{” ancestry that was spreading in many other parts of Europe at that time. We also characterize subsequent genetic influx between the Nuragic period and the present. We detect novel, modest signals of admixture between 1,000 BCE and present-day, from ancestry sources in the eastern and northern Mediterranean. Within Sardinia, we confirm that populations from the more geographically isolated mountainous provinces have experienced elevated levels of genetic drift and that northern and southwestern regions of the island received more gene flow from outside Sardinia. Overall, our genetic analysis sheds new light on the origin of Neolithic settlement on Sardinia, reinforces models of genetic continuity on the island, and provides enhanced power to detect post-Bronze-Age gene flow. Together, these findings offer a refined demographic model for future medical genetic studies in Sardinia

    Feasibility of Iodine and Bromine Analysis in Genesis Solar Wind Collectors

    Get PDF
    Comparison of elemental abundances in sun, meteorites and earth provides understanding of the formation and evolution of the solar system. Yet, the majority of the solar system abundances are based on meteoritic values [1–6]. Here we report an attempt to estimate a feasibility of direct measurements of iodine and bromine in the GENESIS solar wind Aluminum on Sapphire collector (AloS) using neutron induced conversions: ^(127)I(n,ÎłÎČ)^(128)Xe, ^(79)Br(n,ÎłÎČ)^(80)Kr and ^(81)Br(n,ÎłÎČ)^(82)Kr

    Tensile strengths of flocculated compacted unsaturated soils

    Get PDF
    Flocculating agents can be introduced to soils through a number of natural or anthropogenic processes. This paper investigates the effect of flocculant addition (aqueous calcium chloride (CaCl2)) on the tensile strengths of two soils of differing flocculation susceptibility. Tensile strengths were found using the Brazilian (direct splitting) test for a range of suction values. A decrease in tensile strength was found for a soil with high clay content, which was consistent with previous findings in the literature. However, the strength of the soil with lower clay content unexpectedly increased. Results were interpreted using the extended Mohr–Coulomb (EMC) yield criterion fitted to data above the residual suction value. Changes in EMC parameters were used to infer changes in material behaviour on calcium chloride addition. Results have important implications for the design of geotechnical structures, for example engineered cover systems, exposed to flocculating conditions. </jats:p

    The Las Campanas IR Survey: Early Type Galaxy Progenitors Beyond Redshift One

    Get PDF
    (Abridged) We have identified a population of faint red galaxies from a 0.62 square degree region of the Las Campanas Infrared Survey whose properties are consistent with their being the progenitors of early-type galaxies. The optical and IR colors, number-magnitude relation and angular clustering together indicate modest evolution and increased star formation rates among the early-type field population at redshifts between one and two. The counts of red galaxies with HH magnitudes between 17 and 20 rise with a slope that is much steeper than that of the total H sample. The surface density of red galaxies drops from roughly 3000 per square degree at H = 20.5, I-H > 3 to ~ 20 per square degree at H = 20, I-H > 5. The V-I colors are approximately 1.5 magnitudes bluer on average than a pure old population and span a range of more than three magnitudes. The colors, and photometric redshifts derived from them, indicate that the red galaxies have redshift distributions adequately described by Gaussians with sigma_z ~ 0.2centerednearredshiftone,withtheexceptionthatgalaxieshaving centered near redshift one, with the exception that galaxies having V-I3$ are primarily in the 1.5 < z < 2 range. We find co-moving correlation lengths of 9-10 Mpc at z ~ 1, comparable to, or larger than, those found for early-type galaxies at lower redshifts. A simple photometric evolution model reproduces the counts of the red galaxies, with only a ~ 30% decline in the underlying space density of early-type galaxies at z ~ 1.2. We suggest on the basis of the colors, counts, and clustering that these red galaxies are the bulk of the progenitors of present day early-type galaxies.Comment: 5 pages, 3 figures, accepted for publication in the ApJ Letter

    Sexual exploitation in children: Nature, prevalence and distinguishing characteristics reported in young adulthood

    Get PDF
    The aim of this study was to explore the nature and extent of sexual exploitation in a university student sample, whilst being clear that sexual exploitation is sexual abuse. Overall, 47% of participants (96 out of 204) reported having been approached by an adult in a sexual manner when they were under the age of 16. The study predicted that a number of individual characteristics would increase a young person’s vulnerability for sexual exploitation. These included low self-esteem, external locus of control, social loneliness and insecure attachment. Results indicated lower levels of self-esteem among those who had been approached sexually, although it is not clear in terms of causality. There were no differences in scores for locus of control or loneliness. Relationship anxiety was significantly linked with children having engaged in sexual behaviours with an adult. The implications of these findings are discussed in terms of emerging individual characteristics relating to a risk of sexual exploitation

    The Las Campanas Infrared Survey. III. The H-band Imaging Survey and the Near-Infrared and Optical Photometric Catalogs

    Get PDF
    (Abridged) The Las Campanas Infrared Survey, based on broad-band optical and near-infrared photometry, is designed to robustly identify a statistically significant and representative sample of evolved galaxies at redshifts z>1. We have completed an H-band imaging survey over 1.1 square degrees of sky in six separate fields. The average 5 sigma detection limit in a four arcsecond diameter aperture is H ~ 20. Here we describe the design of the survey, the observation strategies, data reduction techniques, and object identification procedures. We present sample near-infrared and optical photometric catalogs for objects identified in two survey fields. We perform object detection in all bandpasses and identify ~ 54,000 galaxies over 1,408 square arcminutes of sky in the two fields. Of these galaxies, ~ 14,000 are detected in the H-band and ~ 2,000 have the colors of evolved galaxies, I - H >3, at z > 1. We find that (1) the differential number counts N(m) for the H-band detected objects has a slope of 0.44 at H 19. In addition, we find that (2) the differential number counts for the H detected red objects has a slope of 0.85 at H 20, with a mean surface density ~ 3,000 degree^{-2} mag^{-1} at H=20. Finally, we find that (3) galaxies with red optical to near-IR colors (I-H > 3) constitute ~ 20% of the H detected galaxies at H ~ 21, but only 2% at H = 19. We show that red galaxies are strongly clustered, which results in a strong field to field variation in their surface density. Comparisons of observations and predictions based on various formation scenarios indicate that these red galaxies are consistent with mildly evolving early-type galaxies at z ~ 1, although with a significant amount of on-going star formation as indicated by the large scatter in their V-I colors.Comment: 48 pages, 13 figures, accepted for publication in the Astrophysical Journa
    • 

    corecore