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This study concerns the eleven monolithic churches in Lalibela, in northeastern Ethiopia, a UNESCO World Heritage Site and currently the main pilgrimage site in Ethiopia. In 2019, on the initiative of Prime Minister, the French authorities proposed their support in the management on the site of the churches. To do so, the French Development Agency (AFD), in collaboration with the Ministry of Europe and Foreign Affairs and with the support of the Ministry of Culture, granted a feasibility study to examine ways of restoring, conserving, and developing the rock-hewn churches. The objective of the feasibility study conducted was to produce the preliminary technical diagnostics required for the preparation of the comprehensive project to restore, conserve, and develop the site. In order to propose a protection and conservation solution, diagnostics and analysis of the pathology of the rocks were made during two campaigns in November 2019 and November 2020. The rock pathology teams implemented non-destructive and minimally invasive analysis. The complementary methods acquire data from the rock surface and the different forms of differential alteration of the scoriaceous basalt. The objective is to characterize, through comparative analyses, the impact of a protective shelter on the alteration kinetics of the rock. The analysis, coupled with on-site observations, suggests that deterioration linked to liquid water and the persistence of a state of high water content is more damaging than the deterioration risk linked to salt crystallization. As water is the key factor in the very harmful alteration for the conservation of scoriaceous basalt as a heritage material in humid natural environments, it seems useful to fully cover the churches. Doi: 10.28991/HEF-2022-03-02-01 Full Text: PDF

El etanol es uno de los combustibles más prometedores en Brasil, pero su producción está centralizada en el cultivo de la caña de azúcar, y actualmente se están buscando otras fuentes de biomasa productora de alcohol para reemplazar el monocultivo de la caña de azúcar. El objetivo de este estudio fue evaluar las variables del proceso de fermentación como el tiempo de fermentación (72 y 96 horas), adición de nutrientes (con y sin adición) y levaduras (levadura orgánica seca y fresca) empleadas en la producción de etanol a partir de dos genotipos de batata (Ipomoea batatas L.): UGA 05 y UGA 77. El contenido del alcohol evaluado en °GL se realizó en un diseño completamente al azar según dos esquemas factoriales (22 y 23), y los resultados obtenidos se analizaron con el software Design Expert® versión 8. Los resultados del diseño factorial 22 indican que el tiempo de fermentación en la producción de alcohol tuvo un efecto significativo en el proceso, lo que sugiere que la producción de alcohol es más eficiente en 72 horas de fermentación y sin la inclusión de nutrientes. En el diseño factorial 23, las interacciones entre el tiempo de fermentación con genotipos, y entre el tiempo y la inclusión de la levadura mostraron efectos significativos y alteraron la producción de alcohol. El proceso de fermentación muestra una diferencia significativa en función del material genético y las levaduras utilizadas, señalando la fermentación del mosto de harina del genotipo UGA 77 bajo acción de levadura fresca y 72 horas de fermentación.

Seasonal change causes variations in soil moisture content. On expansive soil, this condition influences soil moisture content in the active zone, which is approximately in five meters depth. The water content variation induces the changes in soil characteristics and these changes have an impact to adhesion factor of piles. The main objective of this research is to investigate the influence of water content variations on adhesion factor of piles. A series of laboratory experiments were conducted considering water content variations. A pile model made of concrete was penetrated to soil sample which was placed in a cylindrical tube of diameter about 15 times the diameter of the pile model. The pile model was loaded until failure to investigate the friction capacity. The results showed that the change of water content have great impact to adhesion factor of piles and its friction capacity decreased up to eight times from drying to wetting condition.

For proper handling of a product knowledge regarding its water content is essential. To provide fast, inexpensive and reliable results, the direct evaporation method of water in oil bath (EDABO) has been proven to be a viable alternative, at all stages of production of the Brazil nut. Therefore, adaptation and validation of the EDABO method for the almonds was developed using ten lots, five for each stage, maintaining the water content range between 3.73 and 29.13% w.b, which is the typical water content range for the product from the collection phase until its final marketing. The oil bath temperatures tested were 150° C to 200° C, from 10 to 10° C for the adaptation step. The results thus obtained were compared with the water content recorded for the same batch employing the vacuum oven method as the standard. In the adaptation step the most suitable temperature range was set. Next, the method was validated to test for the precision, accuracy and linearity of the pre-set temperature range. During this step, temperature of 150° C were observed to ensured water content results consistent with those determined by the standard method. In the validation step the temperature of 150° C revealed precision, accuracy and linearity and were comparable to the standard method. Therefore, considering the technical aspects for implementation of this method, it was concluded that 150° C temperature was validated.

In this paper we develop a method to estimate land-surface water content in amostly forest-dominated (humid) and topographically-varied region of eastern Canada. Theapproach is centered on a temperature-vegetation wetness index (TVWI) that uses standard 8-day MODIS-based image composites of land surface temperature (TS) and surface reflectanceas primary input. In an attempt to improve estimates of TVWI in high elevation areas, terrain-induced variations in TS are removed by applying grid, digital elevation model-basedcalculations of vertical atmospheric pressure to calculations of surface potential temperature(θS). Here, θS corrects TS to the temperature value to what it would be at mean sea level (i.e.,~101.3 kPa) in a neutral atmosphere. The vegetation component of the TVWI uses 8-daycomposites of surface reflectance in the calculation of normalized difference vegetation index(NDVI) values. TVWI and corresponding wet and dry edges are based on an interpretation ofscatterplots generated by plotting θS as a function of NDVI. A comparison of spatially-averaged field measurements of volumetric soil water content (VSWC) and TVWI for the 2003-2005 period revealed that variation with time to both was similar in magnitudes. Growing season, point mean measurements of VSWC and TVWI were 31.0% and 28.8% for 2003, 28.6% and 29.4% for 2004, and 40.0% and 38.4% for 2005, respectively. An evaluation of the long-term spatial distribution of land-surface wetness generated with the new θS-NDVI function and a process-based model of soil water content showed a strong relationship (i.e., r2 = 95.7%).

Natural polymers, as cellulose, with hydrophilic groups such as hydroxyl groups have various strengths of interaction with water. Cellulose is a structurally heterogeneous polymer, consisting of paracrystalline and amorphous domains. Water can interact with the amorphous domains, but it is excluded almost completely from the crystalline regions. The purpose of this study was to estimate the amount of bulk free water in cellulose based materials, as linen, cotton and paper, by measuring the heats of vaporisation. Moreover the amount of free water in oxidised and grafted samples has been determined by DSC and this quantity has been compared with that found in the corresponding native materials. In oxidised cellulose the water content increases with decreasing the degree of crystallinity; the oxidation, being a degradative reaction, modifies the amorphous content in the cellulose. In presence of acrylic grafted polymer, the free water content is reduced and this reduction is related to the grafting yields. [ABSTRACT FROM AUTHOR]

The effects of water content of three-phase emulsions and engine speed on the combustion and emission characteristics of diesel engines were investigated in this study. The results show that a larger water content of water-in oil (W/O) and oil-in-water-in-oil (O/W/O) emulsion caused a higher brake specific fuel consumption (bsfc) value and a lower O2, as well as a lower NOx emission, but a larger CO emission. The increase in engine speed resulted in an increase of bsfc, exhaust gas temperature, fuel-to-air ratio, CO2 emission and a decrease of NOx, CO emission, and smoke opacity. Because of the physical structural differences, the three-phase O/W/O emulsions were observed to produce a higher exhaust gas temperature, a higher emulsion viscosity and a lower CO emission, in comparison with that of the two-phase W/O emulsion. In addition, the use of W/O emulsions with water content larger than 20% may cause diesel engines to shut down earlier than those running on O/W/O emulsions with the same water content. Hence, it is suggested that the emulsions with water content larger than 20% are not suitable for use as alternative fuel for diesel engines. [ABSTRACT FROM AUTHOR]

In Sedum wrightii grown in a growth chamber, detached leaves could survive for at least 120 d with a high rate of success for propagule formation. The pattern of gas exchange, associated with CAM, may be important in extending the period during which the detached leaf remains physiologically active. The added benefit for the developing propagule, still attached to the “parent” leaf, is an additional source of water and saccharide reserves over an extended period necessary for rooting. Drought survival of propagules may be determined by the amount of water-storing tissue in the detached leaf. [ABSTRACT FROM AUTHOR]

Mineral uptake by winter wheat (Trilicum aestivum L. cv. Martonvasari 8) was studied throughout the life cycle. Accumulation of macronutrients (i.e. total nitrogen, phosphorus, potassium, sodium, magnesium and calcium) and the water content of roots and shoots of plants grown in complete nutrient solution were higher than those of plants grown in two types of soils. The supply of macronutrients was in some cases limiting for soil‐grown plants as revealed by a comparison of available and accumulated amounts of these nutrients. Their supply was abundant, however, for solution‐grown plants. This led to a doubling of grain yield for the latter plants with a three fold increase in accumulation of dry matter and a five‐fold increase in fresh weight. The efficiency ratios of solution‐grown plants to soil‐grown plants were approximately 1 for N and Na, 0.5 for Mg and Ca, and 0.3 for P and K. [ABSTRACT FROM AUTHOR]

Survey data for Norway spruce (Picea abies L.) trees at 12 different forest sites across Europe have been analysed. Three variables (dry weight/fresh weight ratio differences between current and two-year-old needles, ethylene emissions and violaxanthin/antheraxanthin ratios) were found which together show a significant relationship to tree damage in areas affected by forest decline and which are independent of site effects (P < 0.001). Results are also presented that support the contention that atmospheric pollution, especially tropospheric ozone, is the major cause of this problem. After a four-year fumigation experiment, 12-year-old Norway spruce trees showed similar cellular changes as those found in the 30-m 40-ycar-old trees of the survey affected by forest decline. In the fumigation experiment, these changes were most pronounced in those plants exposed to a combination of treatments including ozone, sulphur dioxide and acid rain. The pollutant concentrations used in the four-year study were representative of those experienced by trees growing in affected areas. [ABSTRACT FROM AUTHOR]

Water loss by cell suspensions during centrifugation is well defined by simple physical principles. The major factors affecting water release during centrifugation are: duration of centrifogation, depth of the cell mass, density of cells, relative centripetal acceleration and centripetal force. Water release during centrifugation was best described by an exponential decay process with a decay constant that increases with acceleration from 0.31 ± 0.01 to 0.66 ± 0.12 min−1 (mean ± SE) between 4 825 and 19 300 m s−2, respectively. The cell mass relative water content (RWC) at equilibrium was not a function of rate of water loss and was constant for each acceleration. A centripetal force was generated by the mass of the cells being accelerated away from the axis of rotation. This force generated a pressure that removed some of the cell wall and symplast water, by compression at contact points between the cells and by compression of the cytoplasm. Pressure induced by centripetal forces ranging from −0.02 to −0.23 MPa gave a linear relationship (r2 > 0.99) between force and RWC. The slope (0.900 MPa) was proportional to the cell wall modulus of elasticity (±). and the intercept was interpreted to give the mass of the cells at full turgor without interstitial water (RWC=1). This interpretation is supported by the findings, of two independent experiments. Centrifuged cells suspended at 100% relative humidity for over 48 h reached the same water content as predicted by the intercept. Interstitial water was labelled with solutions of polyethylene glycol (PEG. Mr 8 000), the diameter of which was too large to enter the pores of plant cell walls. Centripetal accelerations greater than 10 900 m s−2 removed PEG‐labelled water to levels below 0.9% of cell water content. Removal of interstitial water and other loosely bound water provided a convenient method for determination of growth, RWC and ±. The centrifugal methods provide the foundation for new quantitative methods for cell culture water relations analyses. [ABSTRACT FROM AUTHOR]

In two experiments, winter wheat (Triticum aestivum cv. Cerco) was grown in 350 (ambient) and 700 μmol mol-1 (elevated) atmospheric CO2 concentrations, In the first experiment, plants were grown at five levels of nitrogen fertilization, and in the second experiment, plants were grown at three levels of water supply. All plants were infected with powdery mildew, caused by the fungus Erysiphe graminis. Plants grown in elevated atmospheric CO2 concentrations had significantly reduced % shoot nitrogen contents and significantly increased % shoot water contents. At elevated atmospheric CO2 concentrations, where plant nitrogen content was significantly reduced, the severity of mildew infection was significantly reduced, and where host water content was significantly increased, the severity of mildew infection was significantly increased. In a moderate water supply treatment, the plants grown in elevated atmospheric CO2 concentrations had significantly reduced nitrogen contents (9.9%) and significantly increased water content (4%), the amount of mildew infection was unchanged. The severity of mildew infection appeared to be more sensitive to host water content than to host nitrogen content. [ABSTRACT FROM AUTHOR]

The nature and kinetics of reactions in dry seeds determines how long the seeds survive. We used gas chromatography to assay volatile organic compounds (VOCs) emitted from seeds of three unrelated species as a means to non-invasively probe chemical changes during very dry, dry, and humid storage (seeds were dried to 5.5, 33, and 75% relative humidity at room temperature). VOCs emitted from seeds stored in humid conditions reflected fermentation-type reactions, with methanol and ethanol being predominant in Lactuca sativa and Carum carvi, and acetaldehyde and acetone being predominant in Eruca vesicaria. Dried C. carvi seeds continued to emit fermentation-type products, although at slower rates than the seeds stored in humid conditions. In contrast, drying caused a switch in VOC emission in L. sativa and E. vesicaria seeds towards higher emission of pentane and hexanal, molecules considered to be byproducts from the peroxidation of polyunsaturated fatty acids. Longevity correlated best with the rate of fermentation-type reactions and appeared unrelated to the rate of lipid peroxidation. Emission of VOCs decreased when seed species were mixed together, indicating that seeds adsorbed VOCs. Adsorption of VOCs did not appear to damage seeds, as longevity was not affected in seed mixtures. Collectively, the study shows similarity among species in the types of reactions that occur in dry seeds, but high diversity in the substrates, and hence the byproducts, of the reactions. Moreover, the study suggests that the most abundant VOCs arise from degradation of storage reserves within seed cells, and that these reactions and their byproducts are not, in themselves, damaging., (© The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

A novel, non-invasive technique for measuring water content in lungsis described. This technique could find important medical applications such as real time monitoring of lung edema development in patientsaffected by cardiac insufficiency undergoing physical effort. The technique is based on the moderation (speed decrease) of fast neutrons crossing the lungs, due mostly to the water contained in lungs. In the application of this diagnostic method, the necessary dose given to the patient is lower than that associated with lung imaging techniques that do not use an image intensifier. The results so far obtained are encouraging, and the method appears to be an improvement over those so far reported in literature as it is able to detect a lung water increase equivalent to 25% of a full edema with a 20% standard error.Research is being performed in order to refine the technique, investigate geometry effects and make the method suitable to the medical field. [ABSTRACT FROM AUTHOR]