428 research outputs found

    Quantification of building energy performance uncertainty associated with building occupants and operators

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    Occupants play an important role in building energy performance, while building operators are the other side of the coin. This research quantifies the relative impact of probabilistic versus standard occupant models on building energy use. Energy performance of a highperformance reference small office building in Ottawa, Canada, is investigated using a simulation-based analysis. The impact of building users is studied by systematically altering occupant and operator-related domains, including occupants\u27 presence and use of lights, window shades, operable windows, plug-in appliances, and thermostats. The results showed that the predicted natural gas energy use increased by a factor of about two compared to the reference occupant models. The predicted electricity energy use decreased about 49% compared to the reference occupant models. This deviation for the gas use resulted from modeling all six domains and for the electricity use resulted from simulating all six domains except for the window shade and operable window use using probabilistic models and operators’ adjusted thermostat setpoints with the air handling unit scheduling to be on all day. The maximum deviation of the predicted electricity energy use with occupants’ adjusted thermostat setpoints caused by the simultaneous probabilistic modeling of the four domains of occupants\u27 presence and use of lighting, plug-in appliances, and thermostat. The lighting use domain showed the highest main effect on the energy use. The findings of the examination of occupant and operator-related modeling assumptions emphasizes the necessity to consider both operators\u27 and occupants\u27 impact on the predicted energy performance of the small building-scale model

    Nonstationary spatiotemporal Bayesian data fusion for pollutants in the near‐road environment

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    Concentrations of near‐road air pollutants (NRAPs) have increased to very high levels in many urban centers around the world, particularly in developing countries. The adverse health effects of exposure to NRAPs are greater when the exposure occurs in the near‐road environment as compared to background levels of pollutant concentration. Therefore, there is increasing interest in monitoring pollutant concentrations in the near‐road environment. However, due to various practical limitations, monitoring pollutant concentrations near roadways and traffic sources is generally rather difficult and expensive. As an alternative, various deterministic computer models that provide predictions of pollutant concentrations in the near‐road environment, such as the research line‐source dispersion model (RLINE), have been developed. A common feature of these models is that their outputs typically display systematic biases and need to be calibrated in space and time using observed pollutant data. In this paper, we present a nonstationary Bayesian data fusion model that uses a novel data set on monitored pollutant concentrations (nitrogen oxides or NOx and fine particulate matter or PM2.5) in the near‐road environment and, combining it with the RLINE model output, provides predictions at unsampled locations. The model can also be used to evaluate whether including the RLINE model output leads to improved pollutant concentration predictions and whether the RLINE model output captures the spatial dependence structure of NRAP concentrations in the near‐road environment. A defining characteristic of the proposed model is that we model the nonstationarity in the pollutant concentrations by using a recently developed approach that includes covariates, postulated to be the driving force behind the nonstationary behavior, in the covariance function.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151876/1/env2581.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151876/2/env2581_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151876/3/ENV_2581-Supp-0001-BDF_supp_material.pd

    Exploring occupants\u27 impact at different spatial scales

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    Buildings\u27 users have widely been accepted as a source of uncertainty in building energy performance predictions. However, it is not evident that the diversity of occupants\u27 presence and behavior at the building level is as important as at the room level. The questions are: How should occupants be modeled at different spatial scales? At the various scales of interest, how much difference does it make if: (1) industry standard assumptions or a dynamic occupant modeling approach is used in a simulation-based analysis, and (2) probabilistic or deterministic models are used for the dynamic modeling of occupants? This paper explores the reliability of building energy predictions and the ability to quantify uncertainty associated with occupant modeling at different scales. To this end, the impacts of occupancy and occupants\u27 use of lighting and window shades on the predicted building lighting energy performance at the room and building level are studied. The simulation results showed that the inter-occupant variation at larger scales is not as important as at the room level. At larger scales (about 100 offices), the rule-base model, custom schedule model, and stochastic lighting use model compared closely for predicting mean annual lighting energy use

    3D Face Reconstruction from Light Field Images: A Model-free Approach

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    Reconstructing 3D facial geometry from a single RGB image has recently instigated wide research interest. However, it is still an ill-posed problem and most methods rely on prior models hence undermining the accuracy of the recovered 3D faces. In this paper, we exploit the Epipolar Plane Images (EPI) obtained from light field cameras and learn CNN models that recover horizontal and vertical 3D facial curves from the respective horizontal and vertical EPIs. Our 3D face reconstruction network (FaceLFnet) comprises a densely connected architecture to learn accurate 3D facial curves from low resolution EPIs. To train the proposed FaceLFnets from scratch, we synthesize photo-realistic light field images from 3D facial scans. The curve by curve 3D face estimation approach allows the networks to learn from only 14K images of 80 identities, which still comprises over 11 Million EPIs/curves. The estimated facial curves are merged into a single pointcloud to which a surface is fitted to get the final 3D face. Our method is model-free, requires only a few training samples to learn FaceLFnet and can reconstruct 3D faces with high accuracy from single light field images under varying poses, expressions and lighting conditions. Comparison on the BU-3DFE and BU-4DFE datasets show that our method reduces reconstruction errors by over 20% compared to recent state of the art

    Associations of the systolic and diastolic components of orthostatic hypotension with markers of cardiovascular risk in older men: A cross-sectional analysis from The British Regional Heart Study

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    The mechanisms underlying the association between orthostatic hypotension (OH) and cardiovascular disease are unclear. We investigated whether OH is associated with circulating cardiovascular risk markers. This was a cross‐sectional analysis of 3857 older, community‐dwelling men. “Consensus OH” was defined as a sitting‐to‐standing decrease in systolic blood pressure ≥20 mm Hg and/or diastolic blood pressure ≥10 mm Hg that occurred within three minutes of standing. Multiple generalized linear regression and logistic models were used to examine the association between cardiovascular risk markers and OH. Consensus OH was present in 20.2%, consisting of isolated systolic OH in 12.6%, isolated diastolic OH in 4.6%, and combined systolic and diastolic OH in 3.0%. Concentration of von Willebrand factor, a marker of endothelial dysfunction, was positively associated with isolated systolic OH (OR 1.35, 95% CI 1.05‐1.73) and combined systolic and diastolic OH (OR 2.27, 95% CI 1.35‐3.83); high circulating phosphate concentration, which may reflect vascular calcification, was associated with isolated diastolic OH (OR 1.53, 95% CI 1.04‐2.25) and combined systolic and diastolic OH (OR 2.12, 95% CI 1.31‐3.44), high‐sensitivity troponin T, a marker of myocardial injury, was positively associated with isolated diastolic OH (OR 1.69, 95% CI 1.07‐2.65) and N‐terminal pro‐brain natriuretic peptide, a marker of cardiac stress, was positively associated with combined systolic and diastolic OH (OR 2.14, 95% CI 1.14‐4.03). In conclusion, OH is associated with some cardiovascular risk markers implicated in endothelial dysfunction, vascular calcification, myocardial injury, and cardiac stress. Clinicians should consider assessing cardiovascular risk in patients with OH

    Evaluation of gut modulatory and bronchodilator activities of Amaranthus spinosus Linn.

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    Background The aqueous-methanolic extract of Amaranthus spinosus (A. spinosus Linn.,) whole plant, was studied for its laxative, spasmolytic and bronchodilator activities to validate some of its medicinal uses. Methods The crude extract of A. spinosus was studied in-vivo for bronchodilator and laxative activities and in-vitro using isolated tissue preparations which were mounted in tissue baths assembly containing physiological salt solutions, maintained at 37°C and aerated with carbogen, to assess the spasmolytic effect and to find out the possible underlying mechanisms. Results In the in-vivo experiments in mice, the administration of A. spinosus increased fecal output at doses of 100 and 300 mg/kg showing laxative activity. It also inhibited carbachol-induced bronchospasm in anesthetized rats at 1, 3, 10 and 30 mg/kg indicative of bronchodilator activity. When tested on isolated gut preparations, the plant extract showed a concentration-dependent (0.01-10.0 mg/ml) spasmogenic effect in spontaneously contracting rabbit jejunum and guinea-pig ileum. The spasmogenic effect was partially blocked in tissues pretreated with atropine (0.1 μM). When tested on K+ (80 mM)-induced sustained contractions in isolated rabbit jejunum, the plant extract caused complete relaxation and also produced a shift in the Ca++ concentration-response curves (CRCs) towards right, similar to diltiazem. In rabbit trachea, the plant extract completely inhibited K+ (80 mM) and carbachol (CCh, 1 μM)-induced contractions at 1 mg/ml but pretreatment of tissue with propranolol (1 μM), caused around 10 fold shift in the inhibitory CRCs of the plant extract constructed against CCh-induced contraction. The plant extract (up to 0.3 mg/ml) also increased both force and rate of spontaneous contractions of isolated guinea-pig atria, followed by relaxation at higher concentration (1.0-5.0 mg/ml). The cardio-stimulant effect was abolished in the presence of propranolol, similar to that of isoprenaline. Activity-directed fractionation revealed that the spasmolytic component(s) was separated in the organic fraction, whereas the spasmogenic component was concentrated in the aqueous fraction. Conclusion These results indicate that A. spinosus possesses laxative activity partially mediated through cholinergic action. The spasmolytic effect was mediated through calcium channel blocking (CCB), while bronchodilator activity through a combination of β-adrenergic and CCB pathways, which may explain the traditional uses of A. spinosus in gut and airways disorders

    Antispasmodic and vasodilator activities of Morinda citrifolia root extract are mediated through blockade of voltage dependent calcium channels

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    <p>Abstract</p> <p>Background</p> <p><it>Morinda citrifolia </it>(Noni) is an edible plant with wide range of medicinal uses. It occurs exclusively in tropical climate zone from India through Southeast Asia and Australia to Eastern Polynesia and Hawaii. The objective of this study was to explore the possible mode(s) of action for its antispasmodic, vasodilator and cardio-suppressant effects to rationalize its medicinal use in gut and cardiovascular disorders.</p> <p>Methods</p> <p>Isolated tissue preparations such as, rabbit jejunum, rat and rabbit aorta and guinea pig atria were used to test the antispasmodic and cardiovascular relaxant effects and the possible mode of action(s) of the 70% aqueous-ethanolic extract of <it>Morinda citrifolia </it>roots (Mc.Cr).</p> <p>Results</p> <p>The Mc.Cr produced a concentration-dependent relaxation of spontaneous and high K<sup>+ </sup>induced contractions in isolated rabbit jejunum preparations. It also caused right ward shift in the concentration response curves of Ca<sup>++</sup>, similar to that of verapamil. In guinea-pig right atria, Mc.Cr caused inhibition of both atrial force and rate of spontaneous contractions. In rabbit thoracic aortic preparations, Mc.Cr also suppressed contractions induced by phenylephrine (1.0 μM) in normal- Ca<sup>++ </sup>and Ca<sup>++</sup>-free Kerb's solutions and by high K<sup>+</sup>, similar to that of verapamil. In rat thoracic aortic preparations, Mc.Cr also relaxed the phenylephrine (1.0 μM)-induced contractions. The vasodilatory responses were not altered in the presence of L-NAME (0.1 mM) or atropine (1.0 μM) and removal of endothelium.</p> <p>Conclusions</p> <p>These results suggest that the spasmolytic and vasodilator effects of Mc.Cr root extract are mediated possibly through blockade of voltage-dependent calcium channels and release of intracellular calcium, which may explain the medicinal use of <it>Morinda citrifolia </it>in diarrhea and hypertension. However, more detailed studies are required to assess the safety and efficacy of this plant.</p

    A broad autism phenotype expressed in facial morphology

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    Autism spectrum disorder is a heritable neurodevelopmental condition diagnosed based on social and communication differences. There is strong evidence that cognitive and behavioural changes associated with clinical autism aggregate with biological relatives but in milder form, commonly referred to as the ‘broad autism phenotype’. The present study builds on our previous findings of increased facial masculinity in autistic children (Sci. Rep., 7:9348, 2017) by examining whether facial masculinity represents as a broad autism phenotype in 55 non-autistic siblings (25 girls) of autistic children. Using 3D facial photogrammetry and age-matched control groups of children without a family history of ASD, we found that facial features of male siblings were more masculine than those of male controls (n = 69; p \u3c 0.001, d = 0.81 [0.36, 1.26]). Facial features of female siblings were also more masculine than the features of female controls (n = 60; p = 0.005, d = 0.63 [0.16, 1.10]). Overall, we demonstrated for males and females that facial masculinity in non-autistic siblings is increased compared to same-sex comparison groups. These data provide the first evidence for a broad autism phenotype expressed in a physical characteristic, which has wider implications for our understanding of the interplay between physical and cognitive development in humans
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