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Contexte : La température moyenne à la surface du globe ne cesse d’augmenter. Elle entraîne notamment une augmentation de la fréquence des vagues de chaleur c’est-à-dire de périodes d’une durée de 3 à 6 jours durant lesquelles la température de l’air est supérieure à la température moyenne de la zone géographique concernée. Cette situation s’accompagne de multiples conséquences pour les populations humaines, végétales et animales. Objectif : Cette revue de littérature a pour objectif de récapituler les concepts fondamentaux régissant la régulation thermique chez les bovins. Méthode : Une recherche bibliographique a été réalisée dans PubMed. Elle s’est concentrée dans un premier temps sur les articles de synthèse puis a été complétée par les références des articles identifiés. Résultats : La régulation thermique implique une série de processus tels que la radiation, la convection, la conduction et l’évaporation. Ces processus vont, en fonction des caractéristiques de l’animal et de son environnement, contribuer à réduire ou à augmenter les effets du stress thermique. Le stress thermique se définit comme l’état de déséquilibre entre, d’une part, les facteurs qui contribuent à augmenter la température corporelle et d’autre part, ceux qui au contraire, contribuent à la diminuer. Cette situation de stress thermique se rencontre quand l’animal se trouve en-dehors de sa zone dite de neutralité thermique définie par des températures minimale et maximale critiques dont les valeurs dépendent de l’âge, la race, le niveau de production, l’état corporel, le stade de lactation, les bâtiments d’élevage, la couleur du poil et de la peau. Les effets de la température extérieure dépendent du degré d’humidité de l’environnement. Ils peuvent être évalués au moyen de divers index THI (Temperature Humidity Index). De plus en plus, des technologies émergent (imagerie en profondeur, thermographie par infrarouge, vidéosurveillance, accéléromètres, podomètres) et permettent de suivre les données météorologiques, l’environnement thermique des animaux, voire de détecter leurs signes de stress. Conclusions : Il est essentiel de sensibiliser les responsables de la santé animale aux effets du stress thermique sur la capacité des animaux à réguler leur température corporelle. Cette capacité peut être évaluée de manière toujours plus précise grâce à des index et des technologies qui permettent de mesurer et de comprendre les effets du stress thermique sur les animaux.

The southeast of the Iberian Peninsula (Spain) is characterized by a significant recurrence of nocturnal temperature inversion processes (ITN), mainly due to the large number of clear days throughout the year. The Segura River Basin District (DHS) has an altitude difference of 2100m in 150km with alternating valley areas and orographically complex and rugged areas. This gives rise to marked night-time thermal contrasts, whose vertical thermal differences are 13.0ºC between cold air pools (CAP) and uneven surfaces. Thermal contrasts are analysed through 58 meteorological observatories in the 50 mornings with the highest intensity of thermal inversion in the last years of observation (2011-2020). Furthermore, the characteristics and triggering causes of such processes are analysed through the analysis of variables influencing the distribution of minimum temperatures (wind, relative humidity, ...). In addition, a high-resolution satellite analysis technique is presented, through the elaboration of thermographies (distribution of surface temperatures) by means of the ASTER sensor, which complement, from the spatial point of view, the distribution of minimum temperatures in the early mornings of ITN in some sectors of the study area. Among the most conclusive results, notable thermal differences stand out during stable early mornings (mean differences of 7.1ºC and absolute differences of 13ºC between observatories located at valley bottoms (CAP) and those located at higher altitudes, in orographically rugged areas), recorded under masses warm and dry air at a geopotential level of 850hPa. [ABSTRACT FROM AUTHOR]

A dual syndrome (zheng), Stagnation of qi (ganyu) and accumulation of Mucus (tan) is a mosaic of single syndromes (zheng). It can still change over time. We present a comprehensive study of the syndrome involving the Liver and Spleen. The clinical observation of a patient who has been followed regularly in periods for a decade will be detailed. All the new situations presented have revolved around the basic syndrome. It is impossible indeed, that the ground of a manifestation is different from an original imbalance of the qixue. It determines all the pathologies that follow. This will be the case for the six different clinical situations we will describe. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Cardiovascular Diseases is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La régénération des huiles lubrifiantes peut être considérée comme une option privilégiée à la conservation des ressources énergétiques et à la réduction des dommages causés à l'environnement. Dans ce contexte, le présent travail a été élaboré en vue de démontrer la faisabilité de régénérer l’huile usagée Repsol32 utilisé comme lubrifiant dans le compresseur de synthèse d’ammoniac du complexe Fertial, Annaba. Le traitement à l’acide sulfurique a montré que pour un ratio VAcide/VHuile égal à 1/20 et une température de 40 °C, la viscosité cinématique et la teneur en eau de l’huile usagée sont nettement améliorées. Les valeurs des différents paramètres physicochimiques entrant dans la caractérisation de l’huile traitée (viscosité, humidité, indice de réfraction et densité) répondent bien aux normes d’utilisation des huiles minérales dans les processus de lubrification.

This study aims to investigate the evolution of hygromechanical properties of flax nonwoven PP composites in a wide range of environmental Relative Humidity (RH) conditions (10, 33, 50, 75 and 98 % RH). The influence of the fibre nature (glass or flax) and porosity (Φ=5, 30, 50 %) is assessed to improve our understanding of the in-service mechanical behaviour of these composites. Flax nonwoven/PP have a complex mechanical behaviour which only becomes amplified at high moisture contents. However, Relative Humidity variations do not affect the performances of glass/PP composites mechanical, whereas the tangent modulus and strain at rupture of flax/PP composites are strongly modified. Interestingly, stress at yield exhibits an improvement with increasing moisture content. [ABSTRACT FROM AUTHOR]

The mechanical behavior of biocomposites and their durability are influenced by the intrinsic properties of the natural fiber reinforcements, especially their high sensitivity to hygro/hydrothermal conditions. To better understand these phenomena, the effect of humidity conditions on the moisture and dimensional variations of natural fiber bundles from several botanical origins with contrasting biochemical and structural characteristics was studied. Results evidenced differences in water uptake and swelling as a function of plant species and allowed to determine hygro/hydroexpansion coefficients of fiber bundles, thus opening interesting perspectives for the predictive modeling of “in-service” mechanical behavior of biocomposites. [ABSTRACT FROM AUTHOR]

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding the physical mechanisms resulting from dry sliding contact disc/pads, require an experimental simulation represented by a disc and a pin, under the influence of a number of braking parameters, such as the nature of the disc material and pin, the load applied by the pin in, and the rotational speed of the disc. On the other hand to apprehend the evolution of the tribological behavior of braking materials, it is a critic to understand the answer of the brake disc materials in the environments especially in the littoral environment where humidity and salinity rate are very high. However, the corrosion of the contact emerges because these environments have a large effect on the friction coefficient and the wear of the brake discs materials. [ABSTRACT FROM AUTHOR]

Following the environnement grenelle, reaching 10% of bio-resourced materials in building sector except wood is one of goals until 2020. Among these agro-materials, one can distinguish the hemp concrete. Based on hemp hurds and mineral binders including lime or polymer as starch, the hemp composites are appreciated for their hydrothermal and acoustic properties. In this study, a vegetal binder based on starch and extracted from wheat is used with treated and non-treated hemp hurds to form an ecological composite. The studied hemp-starch is prepared with a ratio (H/S = 3,3). Hygrothermal properties such as moisture buffering value, sorption isotherm, water vapor permeability, thermal conductivity, and heat capacity are experimentally studied. The pore size distribution is performed using mercury porosimetry. Results reveal that the hemp-starch composite may be a promising solution in the insulation field due to its relatively low thermal conductivity and capacity to regulate the indoor relative humidity. [ABSTRACT FROM AUTHOR]

Résumé Le but de cette étude était d’évaluer les risques allergiques et la sévérité de l’asthme liés à la sensibilisation aux moisissures. Nous avons mené une étude rétrospective entre septembre 2011 et juillet 2013 sur deux groupes de patients, tous asthmatiques, groupe 1 constitué de patients sensibilisés aux moisissures et groupe 2 patients non sensibilisés aux moisissures, chez lesquels ont été effectués des prick-tests pour les pneumallergènes fongiques. Les critères d’évaluation du contrôle de l’asthme étaient ceux du Global Initiative for Asthma (GINA). Les patients asthmatiques étaient au nombre de 219. Les prick-tests étaient positifs pour au moins une moisissure chez les 44 patients constituant le groupe 1 (20 % de la cohorte) avec une prédominance féminine (71 %). Dans ce groupe 1, l’asthme était partiellement contrôlé dans 68 % des cas versus 31 % dans le groupe 2 ( p < 0,001) ; l’asthme était contrôlé dans seulement 25 % des cas dans le groupe 1 versus 57 % dans le groupe 2 p < 0,001). À travers ce travail, les auteurs soulignent que la sensibilisation aux moisissures est non négligeable au Maroc et constitue un facteur de risque de mauvais contrôle de l’asthme. La sensibilisation aux moisissures doit être recherchée devant tout asthme sévère. The aim of this study was to evaluate the control of symptoms in asthmatic patients and its relation to sensitization to molds. This retrospective study, which took place between September 2011 and July 2013, included 219 asthmatic patients which we divided into two groups: group 1 was composed of the 44 patients (20% of the patients, of which 71% were females), who were sensitized to at least one mold and group 2 was composed of the 175 patients (62% females), who were not sensitized to molds, this diagnosis having been established by prick-tests for allergic sensitivity to airborne molds. We used the Global Initiative for Asthma (GINA) as the basis for the evaluation of asthma control. We found that asthma was “partially controlled” in 68% of group 1 patients but “partially controlled” in only 31% of group 2 patients ( P < 0.001). In contrast, asthma was “controlled” in only 25% of group 1 patients compared to 57% in group 2 who were “controlled” ( P < 0.001). As a result of this study, we point out that sensitization to molds is not rare in Morocco and constitutes a risk factor for poor control of asthma, and we recommend that sensitization to molds should be considered in all patients with poorly controlled asthma. [ABSTRACT FROM AUTHOR]

Trees form the terrestrial interface with the atmosphere in forested regions. The electrical properties of trees may influence their response to atmospheric conditions and potentially lethal phenomena (e.g., lightning). We review the literature describing electrical properties of trees and provide a tabular summary of the methods and goals of each study. We hypothesized that electrical resistivity varies consistently among species and between growth forms. We surveyed resistivity of eight tree and three vine species in Michigan and Kentucky, and we quantified resistivity over a moisture gradient for wood blocks of four tree species. Resistivity varied predictably with stem diameter and differed among species and growth forms. Specifically, resistivity of trees was approximately 200% higher than resistivity of vines, and resistivity of conifers was 135% higher than that of hardwoods. The regional comparison showed no difference in resistivity of red maple ( Acer rubrum L.) and sugar maple ( Acer saccharum Marsh.) between Michigan and Kentucky. These results, in combination with interspecific differences observed among wood blocks, suggest that there is a phylogenetic basis for variation in resistivity that reflects differences in anatomy and physiology. Our review and empirical survey provide a framework for studying the ecological effects of lightning in the context of the electrical properties of trees. [ABSTRACT FROM AUTHOR]

This work, which returns within the framework of a research program of the ITGC in Oued Smar, concerns an analysis of three farming techniques effect, for the cereal installation, on the soil properties physics and the consequence on the roots development and on the durum wheat yield. The results analysis shows clearly that the technique used has an effect on the evolution of moisture, on the porosity and on the penetrometric resistance of the soil. The water content in the soil is preserved better with the direct drilling, its value reaches from 12,97% before sowing to 16,51% at the ear development stage on the plowed parcel (TC); it passes from 13,83% to 16,73% on the minimum tilling (TM) parcel and from 14,28% to 18,27 on the direct drilling (SD) parcel. Porosity is slightly more important with the conventional technique. As regards penetrometric resistance, the soil is more resistant on the parcel in direct drilling where it reaches 15,84 daN/cm 2. The results obtained also show that the roots system is developed more on parcel worked with the conventional method than on those worked in direct drilling and minimum work. The estimated yield are respectively 36,19 q/ha for the direct drilling and 50,03 q/ha for conventional work and it is only 35,7 q/ha on the parcel worked with the chisel. [ABSTRACT FROM AUTHOR]

Temperature and moisture heterogeneity, with non-uniform airflow in cold rooms was observed in several studies. This heterogeneity can lead to a deterioration of food quality and safety. Heat and mass transfer in cold rooms is a complex phenomenon because of the presence of the product (airflow modification, heat of respiration…) and the coupling between heat transfer and airflow. Temperature, velocity, humidity and heat transfer coefficient measurements were carried out in a ventilated cold room filled with four apple pallets. The front pallets near the cooling unit were submitted to higher air temperatures compared to the rear ones, leading to product cooling rate and temperature heterogeneity. The experimental results allow the understanding of mechanism of airflow as well as heat and water exchanges between product and air. [ABSTRACT FROM AUTHOR]

Litter respiration ( RL) represents a significant portion of whole-soil respiration ( RS) in forests, yet climatic correlations with RL have seldom been examined. Because RL is reduced at low humidities and RS is reduced at low temperatures, these components may show divergent trends with elevation in western North American forests. Using a litter-removal experiment along a forested 750 m elevation gradient in the Rocky Mountains of northern Idaho, USA, we measured RS on soils from which litter had been removed ( RNL) and, by difference, RL. Mean RL represented 16% (SE = 2%) of mean RS from July through October of 2007 and 2008. RS was highest at warmer times and sites, and was not suppressed by low soil moisture. In contrast, RL was highest at cooler times, when humidity and gravimetric litter water content were highest. RL was highest at mid-elevations, representing neither the warmest nor wettest sites. Sixty-three percent of variability in site RL was explained by both mean annual temperature (MAT) and mean annual relative humidity (MARH), including a positive interaction effect between MAT and MARH. Our results imply that the equilibration of litter with atmospheric humidity is an important control over litter respiration rates. [ABSTRACT FROM AUTHOR]

Abstract: Temperature distribution equation and refrigeration efficiency for fully wet circular porous fins with variable sections are introduced in this study by a new modified wet fin parameter presented by Sharqawy and Zubair. This parameter can be calculated without knowing the fin tip condition by considering the temperature and humidity ratio differences for the driving forces of heat and mass transfer, respectively. It's assumed that heat and mass convective coefficients vary with fin temperature and heat transfer through porous media is simulated using passage velocity from the Darcy's model. After presenting the governing equation, Least Square Method (LSM) and fourth order Runge-Kutta method (NUM) are applied for predicting the temperature distribution in the sample aluminum porous fins. After that, effects of porosity, Darcy number, Rayleigh number, Lewis number and etc. on fin efficiency are examined. As a main outcome, for reaching to high values of fin efficiency, rectangular fin should be used instead of convex and triangular sections. [Copyright &y& Elsevier]

Résumé: But de l’étude: Dans les pays occidentaux, la population urbaine passe environ 90 % de son temps dans un lieu fermé. Les différentes politiques énergétiques axées sur l’amélioration de l’isolation et des chauffages des habitats ont parfois entraîné une modification du point de rosée et un défaut de ventilation. Ces modifications ont abouti à une augmentation de l’humidité favorisant le développement fongique. Les effets néfastes des moisissures sur la santé sont connus mais le rôle d’une exposition aiguë ou chronique au domicile reste peu étudié. Cette étude a pour objectif de présenter le niveau de contamination fongique des logements de patient en Lorraine réalisé par une conseillère médicale en environnement intérieur (CMEI). Résultats: Ils ont montré une médiane de contamination à 195UFC/m3 d’air avec un taux d’humidité relatif de 52,4 % et une température de 21,4°C. Elle n’est pas significativement différente dans les logements présentant de l’humidité et/ou un défaut de ventilation. Les genres les plus fréquemment retrouvés sont les Aspergillus puis les Penicillium puis Alternaria, Cladosporium connus pour avoir des effets allergènes ou infectieux. Conclusion: Le manque de standardisation des mesures rend la comparaison des études difficiles mais une norme ISO est apparue récemment. L’ensemble des méta-analyses synthétisées dans le guideline de l’Organisation mondiale de la santé confirme que l’exposition aux moisissures entraîne un risque pour la santé, en particulier respiratoire. L’amélioration des connaissances et l’éducation à la qualité de l’air intérieur par les CMEI pourraient aider à la prise en charge des patients en particulier allergiques. [ABSTRACT FROM AUTHOR]

Abstract: Frosting to a cooling solid surface is often unavoidable and is severe problems. Thus, in order to control the frosting, it is necessary to clarify the mechanism of frosting, both scientifically and technologically. Furthermore, when investigating this mechanism, knowing how frost crystals start to form and grow is very important, therefore, frosting from generation to primary growth stage must be clarified. Since frost crystals dimensions are very small in their generation and primary growth stage, it is essential to conduct these investigations at the micro scale level. In this study, using a scanning probe microscope (SPM), frost crystals dimensions/distribution and scraping force of frost crystals, were measured under fixed surface temperatures, comparing influence of humidity with that of surface temperature via a method proposed by one of the authors. Then, correlations among the above frost crystals dimensions/distribution and scraping force were clarified, comparing with influence of cooling solid surface temperature. [Copyright &y& Elsevier]

Résumé: Aspergillus fumigatus est une moisissure se développant particulièrement sur le foin et la paille. L’inhalation de ses spores provoque les symptômes de l’allergie essentiellement l’asthme. Pour préciser la prévalence de la sensibilisation cutanée à A. fumigatus sous nos climats, nous avons mené une étude sur une période de deux ans portant sur 100 patients. La moyenne d’âge a été de 32ans. Nous avons noté une prédominance féminine (63 %). Les patients ont bénéficié d’un interrogatoire minutieux et d’un examen clinique complet. Des prick-tests (PT) pour les principaux pneumallergènes ont été pratiqués avec des extraits standardisés. La prévalence de la sensibilisation cutanée à A. fumigatus a été de 19 %, venant en 3e position après Dermatophagoides pteronyssinus, Dermatophagoides farinae et Blomia tropicalis. Cette sensibilisation a été associée à une ou plusieurs sensibilisations aux autres pneumallergènes. Chez ces patients, sensibilisés à A. fumigatus, l’asthme a été retrouvé dans 16 cas, il a été isolé dans 2 cas, associé à une rhino-conjonctivite dans 8 cas, associé à une rhinite dans 4 cas, associé à une conjonctivite dans 1 cas et à une rhino-conjonctivite et un eczéma dans 1 cas. Une rhino-conjonctivite isolée est retrouvée dans 3 cas. L’asthme a été persistant sévère dans 50 % des cas. De cette étude, ressort la prévalence non négligeable de la sensibilisation à A. fumigatus à Casablanca. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the effects of humidity and temperature on avian influenza virus (AIV) H6N2 persistence in the faecal samples from infected ducks (Anas platyrhynchos). In the study, the bacterial microflora and virus titres were determined using the haemagglutination test on allantoic fluids. The results showed that the persistence of the H6N2 virus could be promoted by humidity and low temperatures in natural conditions.

The fungal pathogen Geomyces destructans, which causes white-nose syndrome in bats, thrives in the cold and moist conditions found in caves where bats hibernate. To aid managers and researchers address this disease, an updated and accessible review of cave hibernacula and cave microclimates is presented. To maximize energy savings and reduce evaporative water loss during winter, most temperate vespertilionid bats in North America select caves with temperatures between 2 and 10 °C, with 60%-100% relative humidity. Generally, the temperature in caves is similar to the mean annual surface temperature (MAST) of a region, which varies by latitude, altitude, and topography. However, MAST for most areas where caves are found in eastern North America is well above 10 °C. Thus, various factors cause cold-air infiltration that reduces temperatures of these caves during winter. These factors include depth of cave, topographic setting, airflow patterns, cave configuration, and water infiltration. Factors affecting humidity, condensation, and evaporation are also addressed. In areas where MAST is above or below the thermal requirements of Geomyces destructans, many caves used by bats as hibernacula may still provide favorable sites for optimal growth of this fungus. [ABSTRACT FROM AUTHOR]

Herein, we present a comparative study of thermo- and environmentally responsive TiO2/SiO2 one-dimensional photonic crystals (Bragg stacks) fabricated by different deposition methods and fabrication schemes, featuring various multilayer nanomorphologies. These include dense multilayer systems processed by physical vapor deposition and wet-chemistry protocols, as well as porous systems, namely, nanoparticle-based optical filters exhibiting textural porosity, and evaporation-induced self-assembled mesoporous Bragg stacks exhibiting predominantly structural porosity, as well as hybrid structures comprising both dense and porous layers. We investigate the spectral shift of the photonic stop band for the different Bragg stack nanomorphologies induced by the humidity-enhanced thermo-optic effect in a temperature range from 15 to 60 °C. We also demonstrate the response and recovery kinetics of the multilayer systems during external changes in ambient humidity. Notably, the choice of fabrication method plays a significant role in the thermal and humidity response of the system. Taking advantage of different material nanomorphologies we can tune the thermal shift of the photonic stop band in the range 0.2-32.9 nm for the Bragg stacks at ambient relative humidity. In addition, we can design dense multilayer systems nonresponsive to humidity and achieve time responses of the porous systems to external changes in humidity ranging from about 1 to 3 s. [ABSTRACT FROM AUTHOR]

This study aims at evaluating the antioxidant activity and antifungal essential oil of lavender. The extraction of essential oil of Lavandula officinalis was performed by steam distillation. The yield of HE increases with time before stabilizing. This yield is about 1.36 ± 0.2%. The analysis of the essential oil of Lavandula officinalis by CGC process has identified 49 compounds. Linalyl acetate (15.26%), Linalool (10.68%), 1,8 - cineole (10.25%), γ?-terpinene (11.2%) and camphor (11.25%) were the main components. The study of antioxidant capacity by the DPPH • method showed the existence of an antioxidant activity of essential oil of dried Lavandula officinalis flowers. Purification and microscopic study of isolated strains permit to identify five types of molds including: Aspergillus, Penicillium, Mucor, Rhizopus and Alternaria. The study of the contamination shows a dominance of Aspergillus and Penicillium. Assessing the antifungal activity revealed inhibition of mold growth for most strains tested. [ABSTRACT FROM AUTHOR]

The article discusses the thermal environmental conditions in broiler transport vehicles during cold climate. It informs that the temperature and humidity level of broiler vehicles must be well maintained in the range of ambient temperature. It also suggests that during cold ambient conditions, moisture must be removed and heat must be redistributed on broiler trailers.

Summary: Objectives: To assess the prevalence of exercise-induced bronchospasm in athletes living in humid tropical environment. Methods: This prospective investigation, carried out in Abidjan in september 2001, have concerned 108 athletes of competition. After a questionnaire relative to asthma and atopie, each athlete underwent an exercise challenge. The temperature and the humidity were recorded. Criteria for exercise-induced bronchospasm was a decrease of the forced expiratory volume in one second greater or equal to 10% and/or a decrease of the peak expiratory flow greater or equal to 15%. Results: The averages of ambient temperature and relative humidity were respectively 30.1±1.6°C et 82.6±6.3%. According to the questionnaire, 13% of athletes were asthmatics or had symptoms of asthma and 36.1% had symptoms of atopie. According to the fall of the forced expiratory volume in 1 second, the fall of the peak expiratory flow and the fall of forced expiratory volume in 1 second and/or peak expiratory flow, the prevalences of exercise-induced bronchospasm were respectively 22.2%, 35.2% and 42.6%. These falls occured especially between the 1st and the 15th minute after exercise. Conclusion: The results of this study were not in favour of the hypothesis according to which inhalation of warm and wet air protected from bronchospasm. [Copyright &y& Elsevier]

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Liquid-desiccant systems have been extensively studied as a way of reducing the latent load on air conditioning systems. Most of the studies have targeted the removal of moisture from air at ambient conditions. The literature about the use of liquid desiccants in low temperature applications is scarce. In this study, a small-scale liquid-desiccant absorber is installed inside a commercial refrigerated warehouse. Its performance under realistic operating conditions inside a pre-cooling room is analyzed. The results show that the dew point temperature of the air downstream of the absorber is comparable to the evaporator surface temperature suggesting the potential to delay the formation of ice on the cooling coil. An internal heat exchanger is used to lower the temperature of the inlet liquid-desiccant flow to the absorber and the regeneration process is performed using only ambient air. The analysis of the reduction in water and energy consumption for a scaled-up system is also performed. [ABSTRACT FROM AUTHOR]

Stable isotopes are powerful research tools in environmental sciences and their use in ecosystem research is increasing. Stable isotope measurements allow the study of evapotranspiration fluxes, soil evaporation and leaf transpiration phenomena. Soil water and leaf water are the sources of the evapotranspiration that transfers large quantities of water from land to the atmosphere; as a result the isotopic composition of water left in the leaves is modified towards enrichment. Evaporation also changes the isotopic composition of water bodies creating a natural isotopic signal. The isotopic identity of soil water affects the oxygen isotopic signature of leaf and stem water. In this paper we present the isotopic data of bulk leaf water, showing the enrichment in isotopic value of oxygen due to evapotranspiration from leaves in conjunction with the isotopic signal of rainwater and other environmental factors such as humidity and temperature. Results suggest that the variation in the values of δ18O of Eucalyptus citriodora, Dalbergia sissoo, Melia azedarach and Pinus roxburghii is due to the seasonal changes in the δ18O of the source water for plants, i. e. rain. It is further observed that leaf water δ18O values are depleted during the months of July, August and September. This occurs due to the following reasons: (a) the sampling areas receive about 50% of the average annual rain during these months, and (b) rainfalls during these months are isotopically depleted compared with winter rains. Citation Butt, S., Ali, M., Fazil, M. & Latif, Z. (2010) Seasonal variations in the isotopic composition of leaf and stem water from an arid region of Southeast Asia. Hydrol. Sci. J. 55(5), 844-848. [ABSTRACT FROM AUTHOR]

Three studies examined the establishment and early growth of trembling aspen (Populus tremuloides Michx.) and balsam poplar (Populus balsamifera L.) from seed. To better understand the differences in initial developmental patterns between both species, we monitored germination and early growth in a washed sand medium with a balanced fertilizer added. Two additional studies used the Ae, Bm, and Bt horizons of a Brunisolic Gray Luvisol soil to test the impact of different soil horizons and conditions (compaction and moisture) on the establishment and early growth of trembling aspen and balsam poplar seedlings. Balsam poplar had faster radicle and leaf area development than trembling aspen and grew similarly in all soil horizons, while trembling aspen only grew well in the Ae horizon, where it outgrew balsam poplar. The superior growth of trembling aspen in the Ae horizon was associated with higher P and organic C relative to the lower horizons. Although germination was lowest on the low-compaction – low-moisture treatment for both species, balsam poplar establishment and early growth were higher than for trembling aspen in all combinations of compaction and moisture. Compared with trembling aspen, the wider establishment niche of balsam poplar is attributed to its faster root development and ability to grow in a range of soil substrates and conditions. [ABSTRACT FROM AUTHOR]