Repeatability of water loss and gain rates of Plethodon cinereus

Water loss and gain rates of amphibians are important to understanding their ecology, especially for plethodontid salamanders. We report the first estimates of repeatability of relative water loss and gain rates of the two major colour morphs of the Eastern Red-backed Salamander, Plethodon cinereus, in the fall and spring seasons. Repeatability of relative water loss in P. cinereus was >0 in the fall but not in the spring. Repeatability of relative water gain was significant for all salamanders pooled in the fall, and was not repeatable in the spring. There were no apparent differences in repeatability of relative water loss or gain between the two colour morphs. Our results suggest that the repeatability of relative water loss and gain rates varies by season, but not by colour morph.

Role of Hydrocolloids in the Structure, Cooking, and Nutritional Properties of Fiber-Enriched, Fresh Egg Pasta Based on Tiger Nut Flour and Durum Wheat Semolina

The aim of this work concerns the manufacturing process of fresh egg tagliatelle labeled as a “source of fiber” based on tiger nut flour and wheat semolina. An attempt to improve the quality attributes and cooking properties of the obtained product was made by means of structuring agents. More specifically, a combination of three hydrocolloids (carboximethylcellulose, CMC; xanthan gum, XG; and locust bean gum, LBG) was tested. A Box–Behnken design with randomized response surface methodology was used to determine a suitable combination of these gums to achieve fewer cooking losses, higher water gain and swelling index values, and better texture characteristics before and after cooking. Positive effects on textural characteristics were observed when incorporating XG into the pasta formulation. Cooking and fiber loss also significantly diminished with the XG-CMC combination over 0.8%. No significant effect was found for the other evaluated parameters. A synergistic interaction between LBG and XG was only significant for the water absorption index. The cooked pasta was considered a source of fiber in all cases.

Estimation of aboveground plant water storage using Sentinel-2 images in a semi-arid area

<p>Aboveground plant water storage (APWS), the total of water storing in aboveground parts of plant, has the function of sustaining the balance between water loss by transpiration and water gain of root uptake. APWS is also essential for plants and hydrological cycle, particularly for semi-arid areas, where water availability is limited. However, APWS varies spatially due to the heterogeneity of natural areas that are composed of a large variety of vegetation types, and studies on the spatial variability of APWS are quite limited in semi-arid areas. To fill this knowledge gap, we established 55 inventory plots with 36 plots in forests and 19 plots in shrubs to detect the spatial variability of APWS using a Random Forest (RF) algorithm and Sentinel-2 images in Mao County, China. Field observations indicated that APWS varied significantly with ecosystems, with the highest APWS in forests. Regardless of ecosystem type, mean APWS in Mao Country was 117.63 Mg ha-1. 10-fold cross-validation suggested that the RF model could reasonably predict APWS (model efficiency = 0.68, root mean square error = 54 Mg ha-1), enabling to capture the spatial variability of APWS. A robust spatial variability of APWS was observed with the highest APWS in forests located high altitude areas, while the lowest APWS was found in shrubs located in low altitude areas. Total APWS was 3.39×107 Mg across the whole study area, which could be used as a valuable natural resource for the semi-arid area. Our study successfully explored the spatial variability of APWS, suggesting the capability of detecting APWS using Sentinel-2 and providing essential data evidence for environmental protection for semi-arid areas.</p>

Estimating the future hydric needs of Baja California, Mexico. Assessment of scenarios to stop being a region with water scarcity

This paper shows the actual conditions of freshwater availability in Baja California (BC), Mexico. It aims to estimate the water needs by 2030, and propose scenarios to move out of the scarce water region classification defined by international organizations. A population of 4.1 million people was defined for year 2030 as a target to provide at least 1,000 m3 of water per capita. As agriculture is the main water consumer in the region, empirical decomposition and optimization methods were used to define the trend line of the principal crops production and to establish the optimum conditions for planted surface reduction and water gain. The results show that by 2030, BC will need a total of 4,105 hm3 of water to be classified as a non-water scarcity region; in 2018, BC had 3,045 hm3 of renewable water per year, therefore 1,060 m3 will be needed. The best option in economic terms to attain this goal was the reduction of croplands in Mexicali with a cost of around 82 million US dollars. Although this option is the best quantitatively, the political and social implications of it are enormous, however, the correct management of the resource in critical conditions will require difficult decisions.

Cellular water analysis in T cells reveals a switch from metabolic water gain to water influx

Cell growth is driven by the acquisition and synthesis of dry biomass and water mass. This study examines the increase of water in T cells biomass during cell growth. We found that T cell growth is initiated by a phase of slow increase of cellular water, followed by a second phase of rapid increase in water content. To study the origin of the water gain, we developed a novel method, Cold Aqua Trap – Isotope Ratio Mass Spectrometry (CAT-IRMS), which allows analysis of intracellular water isotope composition. Applying CAT-IRMS, we discovered that glycolysis-coupled metabolic water accounts on average for 11 femtoliter (fL) out of the 20 fL of water gained per cell during the slow phase. At the end of the rapid phase, before initiation of cell division, a water influx occurs, increasing the water level by three-fold. Thus, activated T cells switch from acquiring metabolic water to incorporating water from the extracellular medium. Our work provides a method to analyze cell water content and an insight into the way cells regulate their water mass.

Water Absorption Behavior on Natural/ Synthetic Fibre Reinforced Polymer Composites

This paper deals with the effect of moisture absorption on single coconut sheath fiber and single glass fibre. Additionally, the moisture effect in fibre reinforced unsaturated polyester composites like coconut sheath (CS) and Glass mat (GM) composite. Initially, CS and GM fibre reinforced polyester composite were produced through hand layup followed by compression moulding method. CS/UPR and GM/UPR composites were made through water treatment by dipping those composites in ordinary water for various time intervals at room temperature to study the water absorption effect. At different time periods, the absorption of water showed gradual increment. The effect of water gain in percentage for CS and GM was observed. From this experiment, it is concluded that the effect of water gain in CS/UPR composite is higher than GM/UPR composite.