Granular Activated Carbon From Agricultural By-Products: Carbon Properties and Their Relationship to Sugar Decolorization Potential.

Representative samples of soft, low density, group 1 (rice straw, rice hulls, sugarcane bagasse) and hard, high density, group 2 agricultural by-products (pecan shells) were converted into granular activated carbons (GACs). Prior to pyrolysis, group 1 by-products were mixed with four binders, sugarcane molasses, sugar beet molasses, corn syrup and coal tar. GACs were produced from group 1 and 2 materials by physical activation (carbon dioxide, steam) or from group 2 materials by chemical activation (phosphoric acid). Carbons were evaluated for their physical (hardness, bulk density), chemical (ash, pH), surface (total surface area, pore size distribution, surface oxides) and adsorption properties (molasses color removal, sugar decolorization). Principal component and cluster analyses were used to compare agricultural by-product-based GACs to two commercial reference carbons. The results show that the type of by-product, binder and activation method determine the properties of activated carbons, with surface properties being the most influential on the decolorizing capacity of GACs. Combination of sugarcane or sugar beet molasses with group 1 materials, for instance, was unsatisfactory because it yielded GACs that were brittle and possessed low surface area, low bulk density, high pH and excessive ash content. The use of coal tar yielded GACs with good physical, chemical and surface properties, but with very limited surface area and, thus poor adsorption efficiency. Regardless of the binder, sugarcane bagasse showed a better potential than rice straw or rice hulls as precursor of GACs with the desirable properties of a sugar decolorizing carbon. Pecan shells produced GACs that were closest to the reference carbons. Steam and phosphoric acid activation showed promise in producing GACs with characteristics similar to the commercial carbons. Steam activation of pecan shells produced the best carbon among the agricultural by-product-based GACs and produced GAC with high surface area, good pore size distribution and weakly charged surface, which are good characteristics for sugar decolorizers. This study demonstrated that agricultural by-products can be used to produce GACs that are as effective as the commercial carbons in removing sugar colorants, offering a potential low cost alternative to the existing coal-based commercial carbons used in the sugar refining industry

Granular Activated Carbons from Agricultural By-products: Preparation, Properties, and Application in Cane Sugar Refining (Bulletin #869)

The objectives of this investigation were to convert select Louisiana agricultural by-products to GAC and to characterize these carbons in terms of those physical (surface area, pore structure) and chemical (surface charge, functional groups) properties directly related to adsorption of raw sugar colorants.https://digitalcommons.lsu.edu/agcenter_bulletins/1038/thumbnail.jp

Biochars From Solid Organic Municipal Wastes For Soil Quality Enhancement

The overall municipal organic waste in Qatar accounts for 57% of municipal waste generated annually. Organic solid wastes such as food, newspapers, packaging, furniture woods and wood from building demolition have traditionally been placed in landfill, which create issues of sustainability for a country like Qatar with small land mass. While the recently opened Doha solid waste treatment facility contributed to alleviating the pressure on Landfill sites through composting and incineration, new value-added use of solid organic waste are needed for environmental and economic sustainability. Fortunately, biochars from mixed organic solid wastes can be used in soil amendment for food security and long term carbon sequestration for environmental sustainability. We hypothesize that deficiencies in depleted Qatari soils can be remedied by the application of biochars that are custom-designed to possess the right physicochemical characteristics suitable to improve soil fertility. Hence, this study was conducted to (1) Optimize production of biochars from mixed organic waste for desired physicochemical characteristics as soil enhancers. (2) Produce and characterize designer biochars using optimum production conditions for testing in soil incubation experiments. Select municipal organic wastes (newspaper, cardboard, woodchips and landscaping residues) individually and in a 25% blend were used as a precursor for biochar preparation. These residues were chosen due to their commonality in municipal solid waste streams. A complete 5 × 3 × 3 factorial design was used in this study with five biochar precursors (the 4 solid waste materials and a 25% blend/mixture), 3 sets of pyrolysis temperatures (350, 500, and 750°C) and 3 sets of pyrolysis residence time (2, 4 and 6 hrs). Data obtained showed that biochar yield was in the range of 21- 62% across all feedstocks and pyrolysis conditions. The highest yield was observed in newspaper-based biochars pyrolized at 350°C for 2 hrs. Key parameters such as pH, electrical conductivity bulk density and surface area, which positively improve water and nutrient-holding capacity in biochar-amended soil, varied depending on the precursors and production conditions. Bulk density was high in woodchips-based biochars but was similar among all other biochars, irrespective of precursors and pyrolysis conditions. The total surface area of biochars was low but showed dramatic increase in all feedstocks at 700°C pyrolysis temperature. The highest electrical conductivity observed in cardboard-based biochars pyrolized at 700C. Biochars produced from selected waste precursors were acidic except those produced at 700°C temperature where pH became alkaline. The wide range of biochar pH suggests potential tailoring to remediate the specific soil acidity. Cumulatively, biochars showed promising results for improving soil fertility parameters such as better water holding capacity, pH stabilization, and increased electrical conductivity of soil for better aggregation. These findings indicate that solid organic municipal wastes hold promising potential as precursors for manufacturing of value-added biochars with varied physicochemical characteristics allowing them to be used not only as an alternative to bio-waste management and greenhouse gas mitigation but also as means to improve depleted Qatari soil as the country embarks on its ambitious goals of ensuring food security and environmental sustainability.qscienc

Bioactive Components from Ginger, Tea and Apple Prevent Protein Glycation by Trapping Methylglyoxal with Potential in Alleviation of Diabetic Complications

Diabetes is the fifth-deadliest disease in the United States. Most diabetes patients die from diabetic complications, such as renal failure, heart attack or stroke. However, diabetic complications are still neither preventable nor curable. New strategies that can prevent, treat, or cure diabetic complications are needed. Increasing evidence has identified the formation of advanced glycation end products (AGEs) as a major pathogenic link between hyperglycemia and diabetes-related complications. In diabetes, formation of AGEs occurs at a higher rate when compared to non-diabetic normal individuals. Alpha-oxoaldehydes such as methylglyoxal (MGO) and glyoxal (GO), the reactive dicarbonyl intermediates generated during the non-enzymatic glycation between reducing sugars and amino groups of proteins, lipids, and DNA, are precursors of AGEs and exert direct toxicity to cells and tissues. Levels of MGO and GO were observed to be 2-6 times higher in diabetic patients' plasma as compared with healthy people's plasma. In addition, this is complicated by many food products and beverages representing exogenous sources of MGO and GO. It is likely that decreasing the levels of MGO and GO and inhibiting the formation of AGEs will form an important component of future therapy in patients with diabetes. Numerous studies have reported that bioactive components in ginger, tea and apple can prevent diabetes and its related complications. However, the underlying molecular mechanisms are still largely unknown. In this project, we investigated the effect of bioactive compounds in ginger ([6]-shogaol (6S) and [6]-gingerol (6G)), tea (epigallocatechin gallate (EGCG)) and apple (phloretin and phloridzin) to inhibit the formation of AGEs via trapping MGO. We demonstrated for the first time that both [6]-shogaol (6S) and [6]-gingerol (6G), the major active components in ginger, markedly trapped MGO in vitro and consequently formed mono-MGO adducts, 6S-MGO and 6G-MGO, which were purified from the respective chemical reaction and characterized as novel compounds by NMR experiments and LC-MS/MS approaches. We revealed that the ?-carbon of carbonyl group in the side chain of 6S or 6G is the major active site for trapping MGO. We also demonstrated that 6S and 6G could effectively inhibit the formation of MGO-induced AGEs via trapping MGO in a time-dependent manner in the human serum albumin (HSA)-MGO system. Mono-MGO adducts, 6S-MGO and 6G-MGO, were determined to be the major conjugates in 6S- and 6G-treated HSA-MGO assays, respectively, using LC-ESI/MS techniques. These findings showed the potential effects of 6S and 6G on the prevention of protein glycation, suggesting regular consumption of ginger root extract may attenuate the progression of MGO-associated diabetic complications in patients. Similarly, we found that both EGCG and phloretin could inhibit the formation of AGEs through the same pathways. In addition, we also studied whether these compounds could inhibit the formation of AGEs via trapping MGO in high fat diet treated mice. Two different doses of 6G, EGCG and phloretin (25 mg/kg and 75 mg/kg) were given to mice through oral gavage for 16 weeks. Plasma and tissue samples were collected from control and treated mice. The formation of MGO adducts of each compound were analyzed using our established LC/MS methods. The levels of MGO and AGEs were also quantified.qscienc

A Pilot Study On Cognitive-behavioral Approach For Combatting Childhood Obesity In Qatar

Levels of overweight and obesity have reached alarming proportions in Qatar and other Gulf nations. In Qatar, the need to establish national strategies for the prevention and treatment of obesity was recognized in the National Health Strategy 2011-2016, which stresses the need for prevention. The treatment and prevention of childhood obesity is largely through lifestyle changes- encouraging health eating and physical activity. However, changing such behaviors is complex and requires integrated approaches to tackle such a multifaceted problem. In this study, we sought to implement and evaluate a novel weight management program for Qatari school children at the vulnerable age of 9-12 years. The program uses a cognitive-behavioral approach that involves developing social and emotional competences, promotion healthy dietary habits, and development of physical literacy, while enlisting family involvement in an attempt to maintain long term weight loss. This study also sought to take things further by integrating cutting edge insights from behavioral economics. The pilot study was conducted by an interdisciplinary team of collaborators from Qatar (Qatar University, Supreme Education Council, Aspire, Hamad Medical Corporation) and external partners (Imperial College and Leeds Metropolitan University/MoreLife, UK). The study was branded Agdar/???? and involved development of intervention materials, questionnaires, neuropsychological measures, and other study components such as training manuals and virtual world program. A sample of 100 overweight or obese Qatari children (age 9-12) from 5 independent schools participated in the intervention along with a control group. The intervention was conducted in Arabic and consisted of three phases (1) intensive weight loss camps, (2) after-school clubs as consolidation phase, and (3) a maintenance phase using virtual world program. Variables measured included anthropometric (BMI, Fat composition, and Waist circumference, and Blood pressure), Lifestyle (Physical Activity and Dietary questionnaires), and Psychometric assessments (Self-esteem, Subjective well-being, and Impulsivity, including heart monitoring). Overall, 100% of children who participated in the camp lost weight with a significant reduction BMI-SDS (p<0.001). The camp led to a significant improvement in subjective wellbeing in all five dimensions (p<0.01). The afterschool clubs showed a synergistic effect on children who lost weight at camp where further weight loss was achieved in the after school club phase. The overall percentage BMI-SDS reduction (-8.7%) was significantly higher than the required reduction for health benefits in both adolescents (-3%) and adults (-5%). Girls continued to outperform boys in terms of weight loss reduction and maintenance (-11.9 vs. -5.6%, respectively). This success occurred despite pre-camp surveys showing nearly two thirds of children not meeting their daily requirements of fruits and vegetables while consuming calorie-dense fast foods and over half of the participants not engaging in physical activity. Physiological parameters such as standard deviation of the heart beat-to-beat intervals, used as proxy for impulsivity, correlated significantly with BMI-SDS (p<0.035). Children with a higher BMI were less able to withhold their choices (proxy for impulsivity) and the physiological control of their heart rate correlated with this. These findings could help in segmentation of intervention participants into groups to which tailored programs could enhance impact on behavior change.qscienc

Arab female and male perceptions of factors facilitating and inhibiting their physical activity: Findings from a qualitative study in the Middle East

Objectives: Physical inactivity is a leading global risk to health by contributing to obesity and other chronic diseases. Many chronic non-communicable diseases, such as cancer, diabetes, and cardiovascular diseases (CVDs), can be prevented and controlled by modifying lifestyle behaviors such as physical activity [PA]. However, prevalence of insufficient physical activity and obesity is high in the Middle East Region. In Qatar, the incidence rates of CVDs, diabetes, colon, and breast cancer have been rising rapidly. The purpose of this study was to explore facilitators and barriers influencing PA of adult Arab men and women living in Qatar and to understand what they think would be helpful to increase PA. The goal of the research is to identify culturally appropriate and effective interventions that improve the health of Arab population. Design: Using the socioecological model as the theoretical framework, we conducted an exploratory qualitative study with 128 Arab adult men and women living in Qatar. We utilized focus group interviews to collect the data and performed thematic analysis to generate themes. Results: At the individual level, perceived benefits of PA, presence of diseases, person’s will, motivation and goals, and time to exercise influenced the individual’s PA. At the sociocultural level, religious teachings of Islam, cultural, attitude, beliefs, and practices, and informal support influenced the participants’ PA. At the organizational and political level, physical environment to exercise, accessibility of facilities, organizational support, and health information about PA influenced their PA. Conclusion: Arab men and women are aware of the importance and benefits of PA. They have the motivation to be physically active, but in the absence of supportive environment, their knowledge might not translate into action. Creating supportive environments at multiple levels that are conducive to PA is warranted

Médias and the competition law in Mauritania

Identifiés comme acteurs politiques, économiques, sociaux ou encore culturels ayant un rôle et une responsabilité fondamentale dans un monde caractérisé par une mondialisation technologique galopante, les médias semblent évidemment soumis au droit de la concurrence. Pourtant, cette évidence n’en constitue pas une lorsque l’on analyse profondément la question. Les médias sont-ils vraiment soumis au droit de la concurrence ? Parallèlement est-il possible de dire qu’on se dirige résolument vers un droit de la concurrence propre aux médias ? Les relations entre les médias et le droit de la concurrence ont connus plusieurs épisodes en Mauritanie. Tout d’abord, l’épisode initiale au fil duquel le rapport entre les médias et le droit de la concurrence fut fade et monotone puisque l’Etat monopolisait tous les médias. Ensuite, au cours du deuxième épisode, il y a eu une ouverture partielle et partiale des médias à la concurrence et ainsi au droit de la concurrence. Enfin, le troisième et dernier épisode est celui inauguré par l’abolition totale du monopole. Dés lors, ce travail consiste à montrer et démontrer la soumission des médias au droit de la concurrence.Identified as a political, social, cultural or economical actor, having an esential role in the world characterized by soaring globalisation, which is in a staggering peak, media seems to be naturally submitted to the competition law. However, when the question is analysed in a precised and refined way, this obviousness is not right anymore. Are the media really submited to the competition law ? At the same time is it possible to talk about the competition law specific to medias ? Relations between media and the competition law have been faced of several incidents in Mauritania. First of all, during the first incident, the relation between two institutions, it means media and the competition law were bland and dull because of State’s monopolization of all media’s means. Then, there was a partial opening of media to competition. Eventually, the recording of media by the competition law happened during the last incident. This work consists in demonstration of media’s submission to the competition law even though the mediatic product keeps being specific

Les médias et le droit de la concurrence en Mauritanie

Identified as a political, social, cultural or economical actor, having an esential role in the world characterized by soaring globalisation, which is in a staggering peak, media seems to be naturally submitted to the competition law. However, when the question is analysed in a precised and refined way, this obviousness is not right anymore. Are the media really submited to the competition law ? At the same time is it possible to talk about the competition law specific to medias ? Relations between media and the competition law have been faced of several incidents in Mauritania. First of all, during the first incident, the relation between two institutions, it means media and the competition law were bland and dull because of State’s monopolization of all media’s means. Then, there was a partial opening of media to competition. Eventually, the recording of media by the competition law happened during the last incident. This work consists in demonstration of media’s submission to the competition law even though the mediatic product keeps being specific.Identifiés comme acteurs politiques, économiques, sociaux ou encore culturels ayant un rôle et une responsabilité fondamentale dans un monde caractérisé par une mondialisation technologique galopante, les médias semblent évidemment soumis au droit de la concurrence. Pourtant, cette évidence n’en constitue pas une lorsque l’on analyse profondément la question. Les médias sont-ils vraiment soumis au droit de la concurrence ? Parallèlement est-il possible de dire qu’on se dirige résolument vers un droit de la concurrence propre aux médias ? Les relations entre les médias et le droit de la concurrence ont connus plusieurs épisodes en Mauritanie. Tout d’abord, l’épisode initiale au fil duquel le rapport entre les médias et le droit de la concurrence fut fade et monotone puisque l’Etat monopolisait tous les médias. Ensuite, au cours du deuxième épisode, il y a eu une ouverture partielle et partiale des médias à la concurrence et ainsi au droit de la concurrence. Enfin, le troisième et dernier épisode est celui inauguré par l’abolition totale du monopole. Dés lors, ce travail consiste à montrer et démontrer la soumission des médias au droit de la concurrence