436 research outputs found
Cladding strategies for building-integrated photovoltaics
Photovoltaic cladding on the surfaces of commercial buildings has the potential for considerable reductions in carbon emissions due to embedded renewable power generation displacing conventional power utilization. In this paper, a model is described for the optimization of photovoltaic cladding densities on commercial building surfaces. The model uses a modified form of the ‘fill factor’ method for photovoltaic power supply coupled to new regression-based procedures for power demand estimation. An optimization is included based on a defined ‘mean index of satisfaction’ for matched power supply and demand (i.e., zero power exportation to the grid). The mean index of satisfaction directly translates to the reduction in carbon emission that might be expected over conventional power use. On clear days throughout the year, reductions of conventional power use of at least 60% can be achieved with an optimum cladding pattern targeted to lighting and small power load demands
Controls of soil pipe frequency in upland blanket peat
Soil pipes were surveyed in 160 British blanket peat catchments using consistent application of ground penetrating radar. Soil pipes were found in all catchments. The mean frequency of piping was 69 per kilometer of surveyed transect. Land management (moorland gripping) appears to exert the most important control on hillslope pipe frequency in blanket peats. Management practice in peatlands may therefore induce more rapid subsurface erosion, carbon loss and landform denudation via enhanced preferential flow. Topographic position is also important, with topslopes having greater pipe frequencies than footslopes, followed by midslopes with lowest frequencies. Slope gradient, however, is not a significant factor in controlling blanket peat pipe frequency. I propose that peat structural properties inherited from the way a blanket peat develops on a hillslope strongly control pipe network development. This is manifested in the way slope position appears to control pipe frequency. Aspect appears not to influence frequency in blanket peats except that it does play a weak role in catchments with annual precipitation less than 1500 mm. Here southwesterly-facing slopes tend to have more frequent piping
Identifying developmental coordination disorder: MOQ-T validity as a fast screening instrument based on teachers' ratings and its relationship with praxic and visuospatial working memory deficits.
The present study was devoted to test the validity of the Italian adaptation of the Motor Observation Questionnaire for Teachers (MOQ-T, Schoemaker, Flapper, Reinders-Messelink, & De Kloet, 2008) as a fast screening instrument, based on teachers' ratings, for detecting developmental coordination disorders symptoms and to study its relationship with praxic and visuospatial working memory deficits. In a first study on a large sample of children, we assessed the reliability and structure of the Italian adaptation of the MOQ-T. Results showed a good reliability of the questionnaire and a hierarchical structure with two first-order factors (reflecting motor and handwriting skills), which are influenced by a second-order factor (general motor function) at the top. In a second study, we looked at the external validity of the MOQ-T and found that children with symptoms of Developmental Coordination Disorder (children with high scores on the MOQ-T) also had difficulty reproducing gestures, either imitating others or in response to verbal prompts. Our results also showed that children with high MOQ-T scores had visuospatial WM impairments. The theoretical and clinical implications of these findings are discussed
Coordination difficulty and internalising symptoms in adults: A twin/sibling study
Increased anxiety and depression symptoms have been reported in individuals with neurodevelopmental disorders, and have been found to be associated with motor coordination difficulties, but little is known about the aetiology of these associations. This study aimed to assess genetic, shared (making twins/siblings alike) and non-shared (individual-specific) environmental influences on the association between poor coordination and symptoms of anxiety and depressed mood using a sample of adult twin and sibling pairs. Participants were asked about their coordination skill and anxiety and depression symptoms. About half of the variance in coordination difficulty was explained by familial (combined genetic and shared environmental) influences, with the remaining variance explained by non-shared environmental influences. Phenotypic associations between coordination and anxiety (r = .46) and depression symptoms (r = .44) were largely underpinned by shared familial liability for the three traits. Non-shared environment accounted for about a third of the phenotypic association. Results suggest that both familial and non-shared environmental influences play a role in the aetiology of coordination difficulty and its association with internalizing symptoms. The current study highlights that both biological and environmental pathways shared between these symptoms should be examined in future research to inform prevention and treatment approaches in clinical settings
REM Sleep, Prefrontal Theta, and the Consolidation of Human Emotional Memory
Both emotion and sleep are independently known to modulate declarative memory. Memory can be facilitated by emotion, leading to enhanced consolidation across increasing time delays. Sleep also facilitates offline memory processing, resulting in superior recall the next day. Here we explore whether rapid eye movement (REM) sleep, and aspects of its unique neurophysiology, underlie these convergent influences on memory. Using a nap paradigm, we measured the consolidation of neutral and negative emotional memories, and the association with REM-sleep electrophysiology. Subjects that napped showed a consolidation benefit for emotional but not neutral memories. The No-Nap control group showed no evidence of a consolidation benefit for either memory type. Within the Nap group, the extent of emotional memory facilitation was significantly correlated with the amount of REM sleep and also with right-dominant prefrontal theta power during REM. Together, these data support the role of REM-sleep neurobiology in the consolidation of emotional human memories, findings that have direct translational implications for affective psychiatric and mood disorders
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Dyspraxia and autistic traits in adults with and without autism spectrum conditions
BACKGROUND:
Autism spectrum conditions (ASC) are frequently associated with motor coordination difficulties. However, no studies have explored the prevalence of dyspraxia in a large sample of individuals with and without ASC or associations between dyspraxia and autistic traits in these individuals.
METHODS:
Two thousand eight hundred seventy-one adults (with ASC) and 10,706 controls (without ASC) self-reported whether they have been diagnosed with dyspraxia. A subsample of participants then completed the Autism Spectrum Quotient (AQ; 1237 ASC and 6765 controls) and the Empathy Quotient (EQ; 1147 ASC and 6129 controls) online through the Autism Research Centre website. The prevalence of dyspraxia was compared between those with and without ASC. AQ and EQ scores were compared across the four groups: (1) adults with ASC with dyspraxia, (2) adults with ASC without dyspraxia, (3) controls with dyspraxia, and (4) controls without dyspraxia.
RESULTS:
Adults with ASC were significantly more likely to report a diagnosis of dyspraxia (6.9%) than those without ASC (0.8%). In the ASC group, those with co-morbid diagnosis of dyspraxia did not have significantly different AQ or EQ scores than those without co-morbid dyspraxia. However, in the control group (without ASC), those with dyspraxia had significantly higher AQ and lower EQ scores than those without dyspraxia.
CONCLUSIONS:
Dyspraxia is significantly more prevalent in adults with ASC compared to controls, confirming reports that motor coordination difficulties are significantly more common in this group. Interestingly, in the general population, dyspraxia was associated with significantly higher autistic traits and lower empathy. These results suggest that motor coordination skills are important for effective social skills and empathy
Dates as data revisited: A statistical examination of the Peruvian preceramic radiocarbon record
This paper adopts a formal model-testing approach to the Peruvian radiocarbon (14C) record, the site of the first aggregate analysis of this type of archaeological data. Using a large and improved regional dataset of radiometric determinations (n = 1180) from the period 14000–3000 14C years before present, the study performs a comparative analysis of the demographic trajectories of two sub-regions, the desert coast and Andean highlands. Against the backdrop of theoretical models of population growth, and controlling for taphonomic factors and sampling biases, the study performs global significance and permutation tests on the data. These provide a necessary measure of statistical confidence that have hereto been absent from the discussion of pre-Columbian demography. Contrary to the findings of prior work, this study of radiocarbon data in Peru reveals that regional trends in the data are statistically indistinguishable. Further testing and comparison to climate archives is able to illustrate sustained population growth over the entire Holocene epoch in this region, with only a few notable exceptions at the end of the mid-Holocene (5000 cal BP). The findings of the analysis are viewed in relation to the cultural and technological changes that indigenous societies experienced in the timeframe in question, and some directions for methodological advances are suggested
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'The debatable territory where geology and archaeology meet': reassessing the early archaeobotanical work of Clement Reid and Arthur Lyell at Roman Silchester
The first large-scale archaeobotanical study in Britain, conducted from 1899 to 1909 by Clement Reid and
Arthur Lyell at Silchester, provided the first evidence for the introduction of Roman plant foods to Britain,
yet the findings have thus far remained unverified. This paper presents a reassessment of these
archaeobotanical remains, now stored as part of the Silchester Collection in Reading Museum. The
documentary evidence for the Silchester study is summarised, before the results are presented for over a
1000 plant remains including an assessment of preservation, identification and modern contamination.
The dataset includes both evidence for the presence of nationally rare plant foods, such as medlar, and
several archaeophytes. The methodologies and original interpretations of Reid and Lyell’s study are
reassessed in light of current archaeobotanical knowledge. Spatial and contextual patterns in the
distribution of plant foods and ornamental taxa are also explored. Finally, the legacy of the study for the
development of archaeobotany in the 20th century is evaluated
Phytolith Analysis for Differentiating between Foxtail Millet (Setaria italica) and Green Foxtail (Setaria viridis)
Foxtail millet (Setaria italica) is one of the oldest domesticated cereal crops in Eurasia, but identifying foxtail millets, especially in charred grains, and differentiating it from its wild ancestor, green foxtail (Setaria viridis), in the archaeobotanical remains, is still problematic. Phytolithic analysis provides a meaningful method for identifying this important crop. In this paper, the silicon structure patterns in the glumes, lemmas, and paleas from inflorescence bracts in 16 modern plants of foxtail millet and green foxtail from China and Europe are examined using light microscopy with phase-contrast and a microscopic interferometer. Our research shows that the silicon structure of ΩIII from upper lemmas and paleas in foxtail millet and green foxtail can be correspondingly divided into two groups. The size of ΩIII type phytolith of foxtail millet is bigger than that from green foxtail. Discriminant function analysis reveals that 78.4% of data on foxtail millet and 76.9% of data on green foxtail are correctly classified. This means certain morphotypes of phytoliths are relatively reliable tools for distinguishing foxtail millet from green foxtail. Our results also revealed that the husk phytolith morphologies of foxtail millets from China and Eastern Europe are markedly different from those from Western Europe. Our research gives a meaningful method of separating foxtail millet and green foxtail. The implications of these findings for understanding the history of foxtail millet domestication and cultivation in ancient civilizations are significant
Does the history of food energy units suggest a solution to "Calorie confusion"?
The Calorie (kcal) of present U.S. food labels is similar to the original French definition of 1825. The original published source (now available on the internet) defined the Calorie as the quantity of heat needed to raise the temperature of 1 kg of water from 0 to 1°C. The Calorie originated in studies concerning fuel efficiency for the steam engine and had entered dictionaries by 1840. It was the only energy unit in English dictionaries available to W.O. Atwater in 1887 for his popular articles on food and tables of food composition. Therefore, the Calorie became the preferred unit of potential energy in nutrition science and dietetics, but was displaced when the joule, g-calorie and kcal were introduced. This article will explain the context in which Nicolas Clément-Desormes defined the original Calorie and the depth of his collaboration with Sadi Carnot. It will review the history of other energy units and show how the original Calorie was usurped during the period of international standardization. As a result, no form of the Calorie is recognized as an SI unit. It is untenable to continue to use the same word for different thermal units (g-calorie and kg-calorie) and to use different words for the same unit (Calorie and kcal). The only valid use of the Calorie is in common speech and public nutrition education. To avoid ongoing confusion, scientists should complete the transition to the joule and cease using kcal in any context
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