Modelling of rooms with active chilled beams

Active chilled beams (ACBs) are often modelled as generic cooling devices. Due to induction, the air flow discharged from an ACB is several times higher than supplied from the air handling unit, and due to its design, it affects the temperature of the ceiling to a greater extent than an arbitrary cooling device. This paper investigates the impact of taking these features into account when simulating air and operative temperature in a room equipped with an ACB. The building performance simulation software IDA ICE is used for analysis and the simulations are compared with full-scale experiments. The main findings are that simulations which take into account the features mentioned above correspond more closely with measurements. If designing for a certain operative temperature, this reduces the required design cooling capacity. Although negligible in many applications, the magnitude of this reduction is 9% with high-temperature cooling

The Shapes of Cooperatively Rearranging Regions in Glass Forming Liquids

The shapes of cooperatively rearranging regions in glassy liquids change from being compact at low temperatures to fractal or ``stringy'' as the dynamical crossover temperature from activated to collisional transport is approached from below. We present a quantitative microscopic treatment of this change of morphology within the framework of the random first order transition theory of glasses. We predict a correlation of the ratio of the dynamical crossover temperature to the laboratory glass transition temperature, and the heat capacity discontinuity at the glass transition, Delta C_p. The predicted correlation agrees with experimental results for the 21 materials compiled by Novikov and Sokolov.Comment: 9 pages, 6 figure

The Role of Public Health Institutions in Global Health System Strengthening Efforts: The US CDC's Perspective

Peter Bloland and colleagues from the US CDC lay out the agency's priorities for health systems strengthening efforts

The Cost-Effectiveness of New York City’s Safe Routes to School Program

Objective. We evaluated the cost-effectiveness of a package of roadway modifications in New York City funded under the Safe Routes to School (SRTS) program. Methods. We used a Markov model to estimate long-term impacts of SRTS on injury reduction and the associated savings in medical costs, lifelong disability, and death. Model inputs included societal costs (in 2013 US dollars) and observed spatiotemporal changes in injury rates associated with New York City’s implementation of SRTS relative to control intersections. Structural changes to roadways were assumed to last 50 years before further investment is required. Therefore, costs were discounted over 50 consecutive cohorts of modified roadway users under SRTS. Results. SRTS was associated with an overall net societal benefit of $230 million and 2055 quality-adjusted life years gained in New York City. Conclusions. SRTS reduces injuries and saves money over the long run

BIOMASS QUANTIFICATION IN A SEASONAL DECIDUOUS FOREST IN ITAARA, RS, BRAZIL

O presente trabalho foi realizado no munic\uedpio de Itaara, RS, Brasil, em uma Floresta Estacional Decidual secund\ue1ria com 70 anos aproximadamente. O estudo teve como principal objetivo quantificar a biomassa acima do solo na floresta. Para tanto, foram abatidas vinte \ue1rvores distribu\ueddas em cinco classes de di\ue2metros. As \ue1rvores abatidas foram separadas nas fra\ue7\uf5es, madeira do fuste, casca do fuste, galhos e folhas. Em cada fra\ue7\ue3o, foram retiradas amostras para determina\ue7\ue3o da umidade, determinado o peso seco de cada componente. A estimativa da biomassa foi obtida pelo uso da equa\ue7\ue3o log y = b0 + b1 . log DAP. A produ\ue7\ue3o total estimada de biomassa acima do solo foi de 210,0 Mg ha-1. Nessa estimativa, os galhos corresponderam a 48,8%, a madeira do fuste 43,3%, a casca do fuste 5,4%, e as folhas 2,4%.This work was carried out in the city of Itaara-RS, Brazil. The present work has as main objective the quantification of the above ground biomass. To do so, it had been cut down 20 trees and they were distributed in 5 different diameter classes. The trees had been separated in the components stem timber, stem bark, branches and leaves. In each fraction, samples for determination of humidity had been removed, of each component determined the dry weight. The estimate of the biomass was done by the use of the equation log y = b0 + b1 . log DAP. The total production of above ground biomass was 210,0 Mg ha-1. In this estimate, the branches had corresponded to 48,8% of the above ground biomass, followed by the shafts wood with 43,3%, bark with 5,4% and the leaves with 2,4%

ESTIMATE OF LITTER FALL IN SEASONAL DECIDUOUS FOREST IN ITAARA, RS, BRAZIL

O presente trabalho foi realizado na fazenda da Brigada Militar no munic\uedpio de Itaara, RS, Brasil, e teve como principal objetivo avaliar a devolu\ue7\ue3o de serapilheira em uma Floresta Estacional Decidual. Para a coleta de serapilheira, foram demarcadas seis parcelas de 25 m x 17 m cada, alocadas no interior da floresta. Em cada parcela, foram distribu\ueddos cinco coletores, totalizando 30 coletores, constitu\ueddos por uma moldura de ferro de forma circular, com 50 cm de di\ue2metro. As coletas de serapilheira foram realizadas mensalmente, durante um per\uedodo de 2 anos. No laborat\uf3rio, o material foi separado nas fra\ue7\uf5es folhas, galhos finos (< 1 cm) e miscel\ue2nea (flores, frutos, sementes e restos vegetais n\ue3o-identific\ue1veis). Nos dois anos de coleta, houve grande devolu\ue7\ue3o de serapilheira no in\uedcio do inverno e principalmente na primavera, aumentando nos meses de setembro e novembro, no primeiro ano. No segundo ano, apesar da menor devolu\ue7\ue3o mensal, essa tend\ueancia manteve-se mais ou menos constante, indicando um padr\ue3o sazonal nessa floresta. A devolu\ue7\ue3o m\ue9dia anual de serapilheira foi de 7436,0 kg ha-1, com uma distribui\ue7\ue3o relativa de 71,7% de folhas, 16,5% de galhos finos e 11,8% de miscel\ue2nea. N\ue3o foi verificada uma correla\ue7\ue3o significativa entre as vari\ue1veis clim\ue1ticas precipita\ue7\ue3o e temperatura e a devolu\ue7\ue3o de serapilheira.This work was carried out in the farm of the Military Brigade in the city of Itaara, RS, Brazil. The present work has as main objective to evaluate the estimate of litter fall in Seasonal Deciduous Forest. For the litter collection, six plots of 25 m x 17 m had been demarcated, placed in the forest. In each plot, five litter traps had been distributed, totalizing 30 traps. The litter collections had been carried out monthly, during a period of 2 years (December of 2002 to November of 2004). In the laboratory, the material was separated in fractions, leaves, small twigs and miscellaneous (flowers, fruits, seeds and residues not identified). During the two years of collection, it could be observed great litter deposition in the in the beginning of the winter and mainly in the spring with the biggest depositions during September and November, indicating a standard seasonal in this forest. The leaves had been responsible for 71.3% of the composition of the litter, the fine twigs had contributed with 16.7%, and the miscellany with the lesser ratio of 12.1%, in the two years of collection. A significant correlation between the litter deposition and the climatic variables was not verified

Coronary fly-through or virtual angioscopy using dual-source MDCT data

Coronary fly-through or virtual angioscopy (VA) has been studied ever since its invention in 2000. However, application was limited because it requires an optimal computed tomography (CT) scan and time-consuming post-processing. Recent advances in post-processing software facilitate easy construction of VA, but until now image quality was insufficient in most patients. The introduction of dual-source multidetector CT (MDCT) could enable VA in all patients. Twenty patients were scanned using a dual-source MDCT (Definition, Siemens, Forchheim, Germany) using a standard coronary artery protocol. Post-processing was performed on an Aquarius Workstation (TeraRecon, San Mateo, Calif.). Length travelled per major branch was recorded in millimetres, together with the time required in minutes. VA could be performed in every patient for each of the major coronary arteries. The mean (range) length of the automated fly-through was 80 (32–107) mm for the left anterior descending (LAD), 75 (21–116) mm for the left circumflex artery (LCx), and 109 (21–190) mm for the right coronary artery (RCA). Calcifications and stenoses were visualised, as well as most side branches. The mean time required was 3 min for LAD, 2.5 min for LCx, and 2 min for the RCA. Dual-source MDCT allows for high quality visualisation of the coronary arteries in every patient because scanning with this machine is independent of the heart rate. This is clearly shown by the successful VA in all patients. Potential clinical value of VA should be determined in the near future

Molecular astronomy of cool stars and sub-stellar objects

The optical and infrared spectra of a wide variety of `cool' astronomical objects including the Sun, sunspots, K-, M- and S-type stars, carbon stars, brown dwarfs and extrasolar planets are reviewed. The review provides the necessary astronomical background for chemical physicists to understand and appreciate the unique molecular environments found in astronomy. The calculation of molecular opacities needed to simulate the observed spectral energy distributions is discussed

Two novel human cytomegalovirus NK cell evasion functions target MICA for lysosomal degradation

NKG2D plays a major role in controlling immune responses through the regulation of natural killer (NK) cells, αβ and γδ T-cell function. This activating receptor recognizes eight distinct ligands (the MHC Class I polypeptide-related sequences (MIC) A andB, and UL16-binding proteins (ULBP)1–6) induced by cellular stress to promote recognition cells perturbed by malignant transformation or microbial infection. Studies into human cytomegalovirus (HCMV) have aided both the identification and characterization of NKG2D ligands (NKG2DLs). HCMV immediate early (IE) gene up regulates NKGDLs, and we now describe the differential activation of ULBP2 and MICA/B by IE1 and IE2 respectively. Despite activation by IE functions, HCMV effectively suppressed cell surface expression of NKGDLs through both the early and late phases of infection. The immune evasion functions UL16, UL142, and microRNA(miR)-UL112 are known to target NKG2DLs. While infection with a UL16 deletion mutant caused the expected increase in MICB and ULBP2 cell surface expression, deletion of UL142 did not have a similar impact on its target, MICA. We therefore performed a systematic screen of the viral genome to search of addition functions that targeted MICA. US18 and US20 were identified as novel NK cell evasion functions capable of acting independently to promote MICA degradation by lysosomal degradation. The most dramatic effect on MICA expression was achieved when US18 and US20 acted in concert. US18 and US20 are the first members of the US12 gene family to have been assigned a function. The US12 family has 10 members encoded sequentially through US12–US21; a genetic arrangement, which is suggestive of an ‘accordion’ expansion of an ancestral gene in response to a selective pressure. This expansion must have be an ancient event as the whole family is conserved across simian cytomegaloviruses from old world monkeys. The evolutionary benefit bestowed by the combinatorial effect of US18 and US20 on MICA may have contributed to sustaining the US12 gene family