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Phosphogypsum (PG) is the solid waste product of phosphate fertilizer production and is characterized by high concentrations of salts, heavy metals, and certain natural radionuclides. The work reported in this paper examined the influence of PG amendment on soil physicochemical proprieties, along with its potential impact on several physiological traits of sunflower seedlings grown under controlled conditions. Sunflower seedlings were grown on agricultural soil substrates amended with PG at rates of 0, 2.5, and 5 %. The pH of the soil decreased but electrical conductivity and organic matter, calcium, phosphorus, sodium, and heavy metal contents increased in proportion to PG concentration. In contrast, no variations were observed in magnesium content and small increases were recorded in potassium content. The effects of PG on sunflower growth, leaf chlorophyll content, nutritional status, osmotic regulator content, heavy metal accumulation, and antioxidative enzymes were investigated. Concentrations of trace elements in sunflower seedlings grown in PG-amended soil were considerably lower than ranges considered phytotoxic for vascular plants. The 5 % PG dose inhibited shoot extension and accumulation of biomass and caused a decline in total protein content. However, chlorophyll, lipid peroxidation, proline and sugar contents, and activities of antioxidant enzymes such as superoxide dismutase and catalase increased. Collectively, these results strongly support the hypothesis that enzymatic antioxidation capacity is an important mechanism in tolerance of PG salinity in sunflower seedlings.

AbstractUsing the panel data of 89 economies from 1995–2012, this study examines the major drivers of agricultural emissions while considering affluence, energy intensity, agriculture value added and economic integration. We find long-run cointegration among the variables. Furthermore, our empirical results based on a dynamic fixed effects autoregressive distributed lag model show that the increases in income and economic integration – proxied by trade and foreign direct investment (FDI) – are the major contributors to higher greenhouse gas (GHG) emissions from agriculture in the short run. Additionally, the increases in income, agriculture value added and energy consumption are the major drivers of agricultural emissions in the long run. Notably, trade openness and FDI inflows have significantly negative effects on GHG emissions from agriculture in the long run. These results apply to methane and nitrous oxide emissions. The empirical findings vary across three subsamples of countries at different development stages.

Glucose, fructose, sucrose and starch are naturally present in cereals. Fermentation of different combinations of these carbohydrates by Lactobacillus fermentum Ogi E1, a sourdough heterofermentative lactobacillus, was investigated to determine effects on fermentation kinetics, growth energetics and alpha-amylase production. Irrespective of the substrate combination, the strain was able to simultaneously produce alpha-amylase and consume starch, glucose, fructose and sucrose. In mixtures of starch with either sucrose or fructose or with both fructose and glucose, yields of alpha-amylase from biomass (Y(amy/x)) were similar to those observed for starch. However, for starch and glucose or starch, glucose, fructose and sucrose mixtures, both Y(amy/x) and the specific rate of alpha-amylase production decreased markedly. In fructose- or sucrose-containing mixtures, mannitol was formed stoichiometrically indicating that fructose served as electron acceptor, and acetate was produced at constant yield from biomass (Y(ac/x)) (1 g acetate g biomass(-1)). Acetate production was expected to confer to the strain a competitive advantage during natural fermentation by improving biomass formation and growth through an increase in the ATP gain. Y(ATP) varied depending on the carbohydrate mixture, indicating different effects of substrate mixtures on the efficiency in ATP coupling to biomass formation. Compared to starch fermentation, the highest value of Y(ATP) (29 g biomass mol ATP(-1)) was estimated for the starch/fructose mixture but no increase in mu(max) was observed. The lowest value (16 g biomass mol ATP(-1)) was obtained for the starch, glucose and fructose mixture, whereas for the mixture of all carbohydrates, Y(ATP) was similar to that obtained with starch alone (20 g biomass mol ATP(-1)) and it was intermediary for the starch and sucrose mixture (17 g biomass mol ATP(-1)). It is concluded that competitiveness of the strain cannot be based on expected energy gain in mixed substrate fermentation involving fructose and sucrose with glucose and starch, but rather on its ability to simultaneously use carbohydrates while producing alpha-amylase and to produce acetic acid. Acetic acid production could enhance the strain capacity to inhibit nonacid-tolerant, competitive microflora at the earlier stage of natural fermentation.

There is considerable interest in simple and effective methods to reduce sitting time and increase energy expenditure, and standing breaks have emerged as a realisable approach in individuals with obesity. The aim of the present study was to determine the extent to which energy expenditure in standing differs from sitting, and whether this energetic and metabolic-related responses are modified following a weight loss program in adolescents with obesity.After body composition assessment (DXA), cardiorespiratory and metabolic variables were continuously recorded (indirect calorimetry) during 10 min while sitting and then during 5 min standing posture before (n = 21; T1) and at the end of a multidisciplinary intervention (n = 17; T2) in adolescents with obesity.Before and after the intervention, energy expenditure and fat oxidation rates were significantly increased in standing compared with sitting. Weight loss did not change the relationship between sitting and standing energy expenditure. Sitting energy expenditure represented 1.0 and 1.1 Metabolic Equivalent of Task at T1 and T2, and increased to 1.1 and 1.2 during standing at T1 and T2, respectively. The percentage of change of android fat mass between T1 and T2 was positively associated with the percentage of change in energy expenditure from sitting to standing at T2.The vast majority of the adolescents with obesity significantly increased their energy expenditure between sitting and standing, both before and after a weight loss intervention. However, the standing posture did not allow breaking the sedentary threshold. Abdominal fat mass is associated with energic profile.

Abstract In proton exchange membrane fuel cells, cost, reliability and durability are important issues that need to be solved before their commercialization. Their performance decrease during operation is attributed, amongst others, to the loss of electrochemical surface area occurring during long-term ageing, after transients or after an incident (faulty operation). These losses are mainly due to catalyst metal degradation and carbon-support corrosion, which are continuous irreversible processes that can dramatically reduce the fuel cell lifetime. In this paper, the phenomena linked to catalyst and carbon-support degradation are reviewed, focusing on those caused by fuel and oxidant starvation, since these faulty conditions are amongst the most critical for fuel cell durability. A description of reactions potentially involved in the catalyst degradation, associated with thermodynamic and kinetic considerations related to fuel cell operation are reviewed. This information is used to interpret the experimental results presented in the literature and reviewed in this paper. Based on these reviews, an analysis of the “reverse decay current mechanism” is performed and an alternative mechanism is suggested together with an experiment that would identify the most likely between them. Finally, some characterization methods or mitigation strategies are listed and an illustrative fault tree is built, pointing out the relationship between causes and symptoms in catalyst degradation.

Aeromonas hydrophila is sometimes considered as a controversial human pathogen and reported to be susceptible to food processing procedures and environmental stresses. In this study, we have shown that early stationary phase cells of A. hydrophila were readily killed during up shifts in temperature (in the range 50-70 degrees C), the course of drying (at relative humidity, temperature and brightness of the laboratory) and after 5 min exposure to 20%, 30% and 40% v/v ethanol. However, this bacterium was found moderately susceptible to down shift to 4 degrees C in nutrient poor water, sodium chloride stresses (1.5 and 2 M) and to 12% and 15% v/v ethanol stresses. Tolerance against 1 M NaCl and 10% v/v ethanol was observed. At ambient temperature (24.5 degrees C), this microorganism exhibited a starvation survival state, which was largely independent of the initial cell concentrations (8.82, 7.71 and 6.76 log units). The cross-protection experiments showed that cells starved for short (1 day) or prolonged (50 days) periods developed increased resistance to down shift at 4 degrees C and ethanol stress. This may be of concern to the food-processing industry from the public health perspective.

Africa is the poorest continent in the world and this poverty is linked to the lack of access to energy of its population. A big part of inhabitants live in rural zones where the lack of energy and in particular of electricity is still more flagrant. The aim of the Micro-grids project was to promote the electrification of rural regions of Senegal by the installation of micro-grids with high content of renewable energies. This paper presents some results of this project. Surveys have been carried out in three regions of Senegal to study the needs of electrical energy of non-electrified rural villages' households. These surveys have led to the estimation of electricity needs of the concerned households. The potential in renewable energies of the three regions has also been examined. It has been concluded that the solar energy potential is excellent while the wind energy potential can be interesting in some specific sites. The biomass could also be an efficient source if livestock farming was properly managed in the future. Moreover, many events have been carried out in the three regions to analyse the obstacles for the development of micro-grids in the Senegalese energy context, and to establish suitable solutions to overcome these obstacles. The results presented in this paper have been used to design a rural electrification kit which is described in another paper. Now the Micro-grids' consortium hopes to set up a new project to apply the designed kit on some rural non-electrified villages.

AbstractMexico is one of the largest agricultural producers in Latin America and generates a large amount of agricultural residue. The aim of this study was to establish the usefulness of four of the main Mexican crops (corn, wheat, sugarcane, and Agave) as feedstock for lignocellulosic bioethanol production. The lignocellulosic residue ratio (RR), defined as weight of residue (in tons) per ton of product, was measured by sampling crop fields in 11 geographic regions of Mexico. The chemical composition, assessed by Fourier‐transform infrared spectroscopy (FTIR) and carbon‐13 nuclear magnetic resonance (13C NMR), and structural composition (extractives, cellulose, hemicellulose, and lignin contents), heating value, and metal content of these lignocellulosic residues were measured. Biorefinery locations, and their theoretical bioethanol production, were suggested using the gravity center method and techno‐economic criteria. The highest RR (1.1 ton of straw per ton of grain) was obtained for wheat straw followed by corn (0.8 ton of stover per ton of grain), sugar cane (0.15 ton of bagasse per ton of cane), and Agave (0.2 ton of bagasse per ton of stem). The composition of these biomasses varied significantly depending on the parental material in extractive compounds, lignocellulosic matter, ashes, hemicellulose, lignin, O‐alkyl C, aromatic C, and carboxyl C. The cellulose crystallinity index and the heating value exhibited small variations among biomasses. Copper, Zn, Cd, and Ni content in the biomasses generally exceeded the European Norm (EN‐Plus FprEN 1496 1‐2 B) for solid biofuels. In total, these agricultural biomasses could be used as feedstock for 34 biorefineries in Mexico with a total bioethanol production potential of approximately 1246 million L year–1. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd

The purpose of this work was to examine whether ursodeoxycholate (UDC), a hydrophilic bile salt, could reduce mitochondrial liver injury from chronic ethanol consumption in rats. Animals were pair-fed liquid diets containing 36% of calories as ethanol or isocaloric carbohydrates. They were randomly assigned into 4 groups of 7 rats each and received a specific treatment for 5 weeks: control diet, ethanol diet, control diet + UDC, and ethanol diet + UDC. Respiratory rates of isolated liver mitochondria were measured using a Clark oxygen electrode with sodium succinate as substrate. Mitochondria from rats chronically fed ethanol demonstrated an impaired ability to produce energy. At the fatty liver stage, the ADP-stimulated respiration (V3) was depressed by 33%, the respiratory control ratio (RC) by 25% and the P/O ratio by 15%. In ethanol-fed rats supplemented with UDC, both the rate and efficiency of ATP synthesis via the oxidative phosphorylation were improved: V3 was increased by 35%, P/O by 8%. All the respiratory parameters were similar in control group and control + UDC group. On the other hand, the number and size of mitochondria were assessed by electron microscopy and computer-assisted quantitative analysis. The number of mitochondria from ethanol-treated rats was decreased by 29%, and they were enlarged by 74%. Both parameters were normalized to control values by UDC treatment. These studies demonstrate that UDC has a protective effect against ethanol-induced mitochondrial injury by improving ATP synthesis and preserving liver mitochondrial morphology. These UDC positive effects may contribute to the observed decrease in fat accumulation and may delay the progression of alcoholic injury to more advanced stages.

Land use/land cover (LULC) change has serious implications for environment as LULC is directly related to land degradation over a period of time and results in many changes in the environment. Monitoring the locations and distributions of LULC changes is important for establishing links between regulatory actions, policy decisions, and subsequent LULC activities. The normalized difference vegetation index (NDVI) has the potential ability to identify the vegetation features of various eco-regions and provides valuable information as a remote sensing tool in studying vegetation phenology cycles. Similarly, the normalized difference built-up index (NDBI) may be used for quoting built-up land. This study aims to detect the pattern of LULC, NDBI, and NDVI change in Lodhran district, Pakistan, from the Landsat images taken over 40 years, considering four major LULC types as follows: water bodies, built-up area, bare soil, and vegetation. Supervised classification was applied to detect LULC changes observed over Lodhran district as it explains the maximum likelihood algorithm in software ERDAS imagine 15. Most farmers (46.6%) perceived that there have been extreme changes of onset of temperature, planting season, and less precipitation amount in Lodhran district in the last few years. In 2017, building areas increased (4.3%) as compared to 1977. NDVI values for Lodhran district were highest in 1977 (up to + 0.86) and lowest in 1997 (up to - 0.33). Overall accuracy for classification was 86% for 1977, 85% for 1987, 86% for 1997, 88% for 2007, and 95% for 2017. LULC change with soil types, temperature, and NDVI, NDBI, and slope classes was common in the study area, and the conversions of bare soil into vegetation area and built-up area were major changes in the past 40 years in Lodhran district. Lodhran district faces rising temperatures, less irrigation water, and low rainfall. Farmers are aware of these climatic changes and are adapting strategies to cope with the effects but require support from government.