Experimental validation of a solar system based on hybrid photovoltaic-thermal collectors and a reversible heat pump for the energy provision in non-residential buildings

This work aims to validate a transient model of a solar hybrid pilot plant based on photovoltaic-thermal (PV-T) collectors integrated via thermal storage tanks with an air-to-water reversible heat pump (rev-HP). The pilot plant is in operation and provides space heating, cooling, domestic hot water (DHW) and electricity to an industrial building located in Zaragoza (Spain). The plant consists of eight uncovered PV-T collectors (2.6 kWe, 13.6 m2), two water tanks and a rev-HP with a nominal thermal power of 16 kW for heating and 10.5 kW for cooling. The validation results show that the transient model fits the experimental performance of the PV-T collectors, with an average error of -16% and 3%, for the thermal and electrical generation respectively. The accuracy of the estimated rev-HP performance depends on the operation mode. The estimated COP in cooling mode has an average error of 14%, while in heating mode has an average error of -10%. The results show that the integration of the thermal and electrical generation of the PV-T collectors with a high-performance rev-HP allows the solar PV-T system to be self-sufficient to satisfy the building energy demand

Report of the International Society of Hypertension (ISH) Hypertension Teaching Seminar organized by the ISH Africa Regional Advisory Group: Maputo, Mozambique, 2016

The International Society of Hypertension (ISH), in fulfilment of its mission of promoting hypertension control and prevention and also of advancing knowledge globally, organizes hypertension teaching seminars or ‘summer schools’ worldwide through the ISH Regional Advisory Groups. In Africa, seven of such seminars have been organized. This is a report of the eighth seminar held in Maputo, Mozambique, April, 2016. The seminar was attended by over 65 participants from 11 African countries. The Faculty consisted of 11 international hypertension experts. The eighth African hypertension seminar was a great success as confirmed by a pre- and post-test questionnaire

Early Trends in Cystatin C and Outcomes in Patients with Cirrhosis and Acute Kidney Injury

Background. Acute kidney injury (AKI) is a common and severe complication in patients with cirrhosis. Progression of AKI to a higher stage associates with increased mortality. Intervening early in AKI when renal dysfunction is worsening may improve outcomes. However, serum creatinine correlates poorly with glomerular filtration in patients with cirrhosis and fluctuations may mask progression early in the course of AKI. Cystatin C, a low-molecular-weight cysteine proteinase inhibitor, is a potentially more accurate marker of glomerular filtration. Methods. We conducted a prospective multicenter study in patients with cirrhosis comparing changes in cystatin and creatinine immediately following onset of AKI as predictors of a composite endpoint of dialysis or mortality. Results. Of 106 patients, 37 (35%) met the endpoint. Cystatin demonstrated less variability between samples than creatinine. Patients were stratified into four groups reflecting changes in creatinine and cystatin: both unchanged or decreased 38 (36%) (Scr−/CysC−); only cystatin increased 25 (24%) (Scr−/CysC+); only creatinine increased 15 (14%) (Scr+/CysC−); and both increased 28 (26%) (Scr+/CysC+). With Scr−/CysC− as the reference, in both instances where cystatin rose, Scr−/CysC+ and Scr+/CysC+, the primary outcome was significantly more frequent in multivariate analysis, and , respectively. However, when only creatinine rose, outcomes were similar to the reference group. Conclusions. Changes in cystatin levels early in AKI are more closely associated with eventual dialysis or mortality than creatinine and may allow more rapid identification of patients at risk for adverse outcomes

The right time and “Pl ACE ”: Optimal management of perioperative angiotensin‐converting enzyme inhibitors

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106879/1/jhm2203.pd

Four New Delta Scuti Pulsators from a Variability Survey of 131 Stars

In a photometric variability survey of 131 stars with B < 14 mag, we have found four new Delta Scuti stars. We were sensitive to oscillation amplitudes as low as a few mmag. The detection rate of short-period (P < 0.1 d) pulsating variable stars, which may be relevant for planned large variability surveys such as GAIA, POI, and even the LSST, was therefore 3%. All four new variable stars have low pulsation amplitude (tens of mmag), and one has a very short period (0.0198 d). This star is one of the fastest known Delta Scuti pulsators. The short period of this variable star makes it observationally tractable, and it may therefore be a particularly good candidate for asteroseismological studies. All four new variable stars will add to the cadre of low-amplitude and relatively short-period Delta Scuti stars that are potentially useful for learning about the structure of stars on or near the main sequence, slightly more massive than the Sun.Comment: To appear in the June 2002 issue of PASP, 9 pages, 6 figure

Isotropic wave turbulence with simplified kernels: Existence, uniqueness, and mean-field limit for a class of instantaneous coagulation-fragmentation processes

The isotropic 4-wave kinetic equation is considered in its weak formulation using model (simplified) homogeneous kernels. Existence and uniqueness of solutions is proven in a particular setting where the kernels have a rate of growth at most linear. We also consider finite stochastic particle systems undergoing instantaneous coagulation-fragmentation phenomena and give conditions in which this system approximates the solution of the equation (mean-field limit)

Marcadores de la calidad y la genuinidad de aceites de sacha inchi extra virgen comerciales

This work tackles the study of the quality and authenticity of oils labeled and commercialized as extra virgin sacha inchi oil. Major and minor components as triglycerides, fatty acid methyl esters, tocopherols, sterols and hydrocarbons are determined as well as other physicochemical parameters (density, viscosity, acidity and peroxide value). The results showed that some of the commercialized oils do not fulfill the basic requirement established in the regulation such as the content of α-linolenic acid, higher than 44.7 or 55.0% in the cases of P. volubilis and P. huayllabambana, respectively. The calculated stigmasterol/campesterol ratio for genuine sacha inchi oils should be around 4, however not all commercial oils analyzed comply with this requirement. The presence of the flavons sesamin and sesamolin indicates the addition of compounds from sesame oils. Finally, some of the commercial oils showed to contain trans fatty acids although this was not accompanied by the sterene hydrocarbon presence.En este trabajo se aborda el estudio de la calidad y la genuinidad de los aceites etiquetados y comercializados como sacha inchi extra virgen. Se estudian los componentes mayoritarios como los triglicéridos y los ésteres metílicos de ácidos grasos, componentes menores insaponificables (tocoferoles, esteroles e hidrocarburos) así como otros parámetros fisicoquímicos (densidad, viscosidad, acidez, peróxidos y estabilidad). Los resultados mostraron que algunos de los aceites comercializados no cumplían con el requisito básico establecido en la normativa de tener un contenido en α-linolénico superior a 44,7 o 55,0% determinado para P. volubilis o P. huayllabambana respectivamente. La relación estigmasterol/campesterol medida en aceites de sacha inchi genuinos es de alrededor de 4, y no todos los aceites comerciales analizados cumplían con este requisito. La presencia de las flavonas sesamina y sesamolina indica la adición de compuestos procedentes de aceites de sésamo. Por último, algunos de los aceites comerciales estudiados, contenían ácidos grasos trans aunque no se detectó en ellos la presencia de hidrocarburos esteroideos

Acute renal failure in an AIDS patient on tenofovir: a case report

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Partitioning of trace elements in a entrained flow IGCC plant: Influence of selected operational conditions

The partitioning of trace elements and the influence of the feed conditions (50:50 coal/pet-coke feed blend and limestone addition) was investigated in this study. To this end feed fuel, fly ash and slag samples were collected under different operational conditions at the 335 MW Puertollano IGCC power plant (Spain) and subsequently analysed. The partitioning of elements in this IGCC plant may be summarised as follows: (a) high volatile elements (70–>99% in gas phase): Hg, Br, I, Cl and S; (b) moderately volatile elements (up to 40% in gas phase and 60% in fly ash): As, Sb, Se, B, F, Cd, Tl, Zn and Sn; (c) elements with high condensation potential: (>90% in fly ash): Pb, Ge, Ga and Bi; (d) elements enriched similarly in fly ash and slag 30–60% in fly ash: Cu, W, (P), Mo, Ni and Na; and (e) low volatile elements (>70% in slag): Cs, Rb, Co, K, Cr, V, Nb, Be, Hf, Ta, Fe, U, Ti, Al, Si, Y, Sr, Th, Zr, Mg, Ba, Mn, REEs, Ca and Li. The volatility of As, Sb, and Tl and the slagging of S, B, Cl, Cd and low volatile elements are highly influenced by the fuel geochemistry and limestone dosages, respectively