384 research outputs found

    SYNTHESIS AND EVALUATION OF ANTIMICROBIAL ACTIVITY OF PHENYL AND FURAN-2-YL[1,2,4] TRIAZOLO[4,3-a]QUINOXALIN-4(5H)-ONE AND THEIR HYDRAZONE PRECURSORS

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    A variety of 1-(s-phenyl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-one (3a-3h) and 1-(s-furan-2-yl)-[1,2,4]triazolo[4,3- a]quinoxalin-4(5H)-one (5a-d) were synthesized from thermal annelation of corresponding hydrazones (2a-h) and (4a-d) respectively in the presence of ethylene glycol which is a high boiling solvent. The structures of the compounds prepared were confirmed by analytical and spectral data. Also, the newly synthesized compounds were evaluated for possible antimicrobial activity. 3-(2-(4-hydroxylbenzylidene)hydrazinyl)quinoxalin-2(1H)-one (2e) was the most active antibacterial agent while 1-(5-Chlorofuran-2-yl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-one (5c) stood out as the most potent antifungal agent

    Optimization of Agro-Socio-Hydrological Networks under Water Scarcity Conditions: Inter- and Trans-disciplinary Approaches for Sustainable Water Resources Management

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    Sustainable agriculture is one of the greatest challenges of our time. The pathways to sustainable agriculture consist of successive decisions for optimization that are often a matter of negotiation as resources are shared at all levels. This work essentially comprises three research projects with novel inter- and transdisciplinary methods to better understand and optimize agricultural water management under water scarcity conditions. In the first project, climate variability in the US Corn Belt was analyzed with a focus on deficit irrigation to find the optimal irrigation strategies for possible future changes. Two optimization methods for deficit irrigation showed positive water savings and yield increases in the predicted water scarcity scenarios. In the second project, a serious board game was developed and game sessions were carried out to simulate the complex decision space of actors in irrigated agriculture under climate and groundwater variability. The aim of the game was to understand how decisions are made by actors by observing the course of the game and linking these results to common behavioral theories implemented in socio-ecological models. In the third project, two frameworks based on innovation theories and agro-social-hydrological networks were developed and tested using agent-based models. In the first framework, centralized and decentralized irrigation management in Kansas US was compared to observe the development of collective action and the innovation diffusion of sustainable irrigation strategies. The second framework analyzed different decision processes to perform a sensitivity analysis of innovation implementation, groundwater abstraction and saline water intrusion in the Al Batinah region in Oman. Both frameworks allowed the evaluation of diverse behavior theories and decision-making parameters to find the optimal irrigation management and the impact of diverse socio-ecological policies. Inter- and Trans-disciplinary simulations of the interactions between human decisions and water systems, like the ones presented in here, improve the understanding of irrigation systems as anthropogenic landscapes in socio-economic and ecological contexts. The joint application of statistical and participatory approaches enables different but complementary perspectives that allow for a multidimensional analysis of irrigation strategies and water resources management.:Contents Declaration of Independent Work i Declaration of Conformity iii List of Publications v Acknowledgments ix Abstract xi Zusammenfassung xiii Contents xv List of Figures xvii List of Tables xix List of Abbreviations xxi 1. Introduction 3 1.1 Complex Networks Approach 3 1.2 Research Objectives 4 1.3 Thesis Outline 5 2. Literature Review 9 2.1 Agro-Hydrological Systems 9 2.1.1 Necessary Disciplinary Convergence 9 2.1.2 Multi-Objective Optimization Approaches 10 2.2 Optimization of Crop-Water Productivity 11 2.2.1 Irrigation Strategies 11 2.3 Sustainable Management of A-S-H Networks 12 2.3.1 Socio-Hydrology 13 2.3.2 Representation of Decision-Making Processes 14 2.3.3 Influence of Social Network 16 2.4 Socio-Hydrological Modeling Approaches 17 2.4.1 Game Theory Approach 17 2.4.2 Agent-Based Modeling 18 2.4.3 Participatory Modeling 20 2.5 Education for Sustainability 21 2.5.1 Experiential Learning 21 2.5.2 Serious Games 22 2.6 Summary of Research Gaps 24 3. Irrigation Optimization in The US Corn Belt 27 3.1 Agriculture in The Corn Belt 27 3.2 Historical and Prospective Climatic Variability 29 3.3 Simulated Irrigation Strategies 29 3.4 Optimal Irrigation Strategies Throughout the Corn Belt 30 3.5 Summary 31 4. Participatory Analysis of A-S-H Dynamics 35 4.1 Decision-Making Processes in A-S-H Networks 36 4.1.1 Collaborative and Participatory Data Collection Approaches 37 4.2 MAHIZ 38 4.2.1 Serious Game Development 38 4.2.2 Implementation of Serious Game Sessions 39 4.4 Evaluation of The Learning Process in Serious Games 40 4.5 Evaluation of Behavior Theories and Social Parameters 42 4.6 Summary 43 5 Robust Evaluation of Decision-Making Processes In A-S-H Networks 47 5.1 Innovation in A-S-H Networks 47 5.1.1 Multilevel Social Networks 48 5.1.2 Theoretical Framework of Developed ABMs 49 5.2 DInKA Model: Irrigation Expansion in Kansas, US 50 5.2.1 Robust Analysis of Innovation Diffusion 53 5.3 SAHIO Implementation: Coastal Agriculture in Oman 54 5.3.1 SAHIO Sensitivity analysis 58 5.4 Summary 60 6 Conclusions and Outlook 63 6.1 Limitations 64 6.2 Outlook 64 Bibliography 69 Appendix A. Implementation Code 79 A.1 DInKA 79 A.2 SAHIO 82 Appendix B. SAHIO’s Decision-Making Process for Each MoHuB Theory 91 Appendix C. SAHIO A-S-H Innovation Results 97 Appendix D. Selected Publications 101 D.1 Evaluation of Hydroclimatic Variability and Prospective Irrigation Strategies in the U.S. Corn Belt. 103 D.2 A Serious Board Game to Analyze Socio-Ecological Dynamics towards Collaboration in Agriculture. 121 D.2.1 MAHIZ Rulebook 140 D.2.2 MAHIZ Feedback Form 15

    Produção, caracterização e aplicação de sólido fermentado lipásico de Penicillium sp. na obtenção de ácidos graxos pela hidrólise de óleo de algodão assistido por ultrassom

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    Orientador: Gabriela Alves MacedoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Esse estudo objetivou o desenvolvimento de um biocatalisador com atividade lipolítica produzida por fermentação em estado sólido (FES) utilizando subprodutos agrícolas como substrato e micro-organismo Penicillium sp. para avaliação da aplicação na hidrólise de óleo de algodão assistido por ultrassom (US). A tese foi dividida em três capítulos, o primeiro é destinado a uma revisão bibliográfica enfatizando a importância do desenvolvimento de uma bioeconomia, na utilização de óleos e gorduras para produtos comerciais, reaproveitamento de biomassa agrícola, novas aplicações da FES, de lipases e a utilização de US na biocatálise. O segundo capítulo relata a produção de lipase por FES utilizando três subprodutos como substratos: farelo de trigo, de soja e de algodão. Planejamento de misturas simplex centroide (PMSC) foi utilizado para avaliar a melhor formulação usando atividade de lipase (U/g) e custo/unidade de atividade (US/103U)comorespostas.Afunc\ca~odesejabilidadeotimizousimultaneamenteasduasrespostas,gerandoumaformulac\ca~ocommaioratividadeemenorcustoparaomeiodefermentac\ca~ousando100/10³U) como respostas. A função desejabilidade otimizou simultaneamente as duas respostas, gerando uma formulação com maior atividade e menor custo para o meio de fermentação usando 100% farelo de algodão, depois utilizado para otimizar os parâmetros físicos na FES: temperatura, relação água/sólido e tamanho de partícula. O delineamento central composto rotacional (DCCR) foi empregado para avaliar os parâmetros atividade de lipase, proteína e atividade específica. As condições ótimas: 30ºC, 70% relação água/sólido e partícula de 2,4 mm de tamanho foram determinados pela função desejabilidade. Essa abordagem permitiu uma redução de 20% de água no meio de fermentação. Para determinar melhor tempo de fermentação os experimentos realizados nas condições ótimas revelaram o melhor tempo em 48 horas e uma redução de 50% do tempo ótimo inicial (96 horas). No terceiro capítulo, o objetivo foi caracterizar a enzima e avaliar a aplicação na hidrólise de óleo de algodão assistido por US e em banho com agitação. A caracterização da lipase compreendeu a determinação das condições ótimas e de estabilidade para temperatura e pH; especificidade (tamanho de cadeia) e estabilidade em solventes orgânicos. As condições ótimas foram: atividade em 40ºC e pH 7 e estabilidade em 30ºC e pH 3. Os resultados indicam maior afinidade por ácidos graxos de cadeia longa (paranitrofenol palmitato p-NPP) e alta estabilidade em solventes apolares (hexano) e baixa em polares (metanol e etanol). Na hidrólise do óleo de algodão, dois experimentos foram conduzidos: em banho com agitação e outro utilizando US através de sonda (19 kHz) em contato direto com meio reacional. Os dois estudos foram desenhados por DCCR e usados como variáveis independentes: concentração de fermentado sólido lipásico (FSL) e relação tampão/óleo para o sistema em banho (40ºC, 120 rpm) e concentração de FSL, relação tampão/óleo e densidade energética (W/mL) para o sistema reacional com US. Os resultados demonstraram que aumento de LSF e relação tampão/óleo resultam em aumento da hidrólise do óleo de algodão. Por outro lado, a potência de US gera diminuição da hidrólise, possivelmente inibindo a reação. As condições ótimas foram as mesmas para os dois sistemas: 20% FSL, relação tampão/óleo de 4. O tempo ótimo de reação foi definido pela função desejabilidade obtendo 30 minutos e 54% de hidrólise para US e 1 hora e 28,5 % para banho com agitaçãoAbstract: This study aimed to develop a biocatalyst with lipolytic activity through solid-state fermentation (SSF) using agricultural byproducts as substrate and a strain of Penicillium sp. to evaluate the application on cottonseed oil hydrolysis assisted by ultrasound (US). Divided into three chapters, the first intended for a literature review emphasizing the importance of developing a bioeconomy, the use of oils and fats for commercial products, agricultural biomass reuse, SSF new applications, lipase and the US in biocatalysis. The second chapter relates to lipase production by SSF using three by-products as substrates: wheat bran (WB), soybean meal (SM) and cottonseed meal (CSM). Simplex centroid mixture design (SCMD) evaluated the best formulation using lipase activity (U/g) and cost/unit (US/10³U) as responses. The function desirability simultaneously optimized both responses, generating the best formulation with higher activity and lower cost using 100% CSM as fermentation medium to optimize the physical parameters of the SSF: temperature, the water/solid ratio and size particle. Central composite rotatable design (CCRD) evaluated the parameters lipase activity, protein and specific activity. The optimum conditions determined by desirability function were: 30°C, 70% water/solid and particle size of 2.4 mm. This approach allowed a reduction of 20% water in the fermentation medium. To determine the best fermentation time, experiments carried out in optimum conditions showed the best time in 48 hours, a 50% reduction from the initial optimum time (96 hours). In the third chapter, the goal was to characterize the enzyme and to evaluate the application in cottonseed oil hydrolysis assisted by US and other in shaking bath. The characterization included the determination of optimum and stability conditions of temperature and pH for lipase activity; specificity (chain size) and stability in organic solvents. The optimum conditions were: 40 °C and pH 7 for activity and 30°C and pH 3 for stability. Higher affinity for long-chain fatty acids (p-NPP) and higher stability in apolar solvents (hexane) and lower in polar (methanol and ethanol). In the hydrolysis of cottonseed oil, two experiments were conducted: in shaking bath and another using US probe (19 kHz) in direct contact with the reaction medium. Both studies were designed by CCRD and used as independent variables: concentration of lipasic solid fermented (LSF) and buffer/oil ratio for the system in bath (40 °C, 120 rpm) and concentration of LSF, buffer/oil ratio and power density (W/mL) to US system. The results showed that increasing LSF and buffer/oil ratio resulted on improvement of cottonseed oil hydrolysis. Nevertheless, the US power generates a decrease, possibly inhibiting the reaction. The optimum conditions were the same for both systems: 20% FSL, buffer/oil ratio = 4 The optimum reaction time defined by the desirability function was 30 minutes and 54% of hydrolysis yield to US and 1 hour and 28.5% for shaking bathDoutoradoCiência de AlimentosDoutor em Ciência de Alimentos141104/2011-2CNP

    Climate-smart agriculture global research agenda: Scientific basis for action

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    Background: Climate-smart agriculture (CSA) addresses the challenge of meeting the growing demand for food, fibre and fuel, despite the changing climate and fewer opportunities for agricultural expansion on additional lands. CSA focuses on contributing to economic development, poverty reduction and food security; maintaining and enhancing the productivity and resilience of natural and agricultural ecosystem functions, thus building natural capital; and reducing trade-offs involved in meeting these goals. Current gaps in knowledge, work within CSA, and agendas for interdisciplinary research and science-based actions identified at the 2013 Global Science Conference on Climate-Smart Agriculture (Davis, CA, USA) are described here within three themes: (1) farm and food systems, (2) landscape and regional issues and (3) institutional and policy aspects. The first two themes comprise crop physiology and genetics, mitigation and adaptation for livestock and agriculture, barriers to adoption of CSA practices, climate risk management and energy and biofuels (theme 1); and modelling adaptation and uncertainty, achieving multifunctionality, food and fishery systems, forest biodiversity and ecosystem services, rural migration from climate change and metrics (theme 2). Theme 3 comprises designing research that bridges disciplines, integrating stakeholder input to directly link science, action and governance. Outcomes: In addition to interdisciplinary research among these themes, imperatives include developing (1) models that include adaptation and transformation at either the farm or landscape level; (2) capacity approaches to examine multifunctional solutions for agronomic, ecological and socioeconomic challenges; (3) scenarios that are validated by direct evidence and metrics to support behaviours that foster resilience and natural capital; (4) reductions in the risk that can present formidable barriers for farmers during adoption of new technology and practices; and (5) an understanding of how climate affects the rural labour force, land tenure and cultural integrity, and thus the stability of food production. Effective work in CSA will involve stakeholders, address governance issues, examine uncertainties, incorporate social benefits with technological change, and establish climate finance within a green development framework. Here, the socioecological approach is intended to reduce development controversies associated with CSA and to identify technologies, policies and approaches leading to sustainable food production and consumption patterns in a changing climate

    Sweet bakery products for diabetic’s diet and analysis of risk associated with selected ingredients

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    Diabetes is a complex, chronic illness that demands a healthy diet. The overall quality of consumed food is important for diabetics, but benefits are expected from whole grains and lower-energy food. Choice of appropriate sweet bakery product may present the problem for diabetics in meal planning. The aim of this research is to provide an overview of some opportunities for new food product development for persons with diabetes and to analyze the risks associated with selected food ingredients, which can be used. It includes identification of special requirements for controlled nutrition. Quality parameters and food product composition are determined on a formulation for muffins modified to contain ingredients recommended and safe for diabetics’ diet with lower energy value, but keeping prescribed and acceptable product quality. The research focuses on assessment of the risks analysis associated with selected ingredients on an example of muffin-like cake formulation modelling and use of wheat flour, sugars, fats, salt and some additional ingredients, milk, eggs and cocoa powder, based on experience, insight into recommendations for diabetics’ nutrition and scientifically identified indicators aimed at health protection. Methodology for the selection of the ingredients for energy-reduced muffin-like cakes with whole-grain wheat flour and cocoa, suitable for diabetics’ diet presented in the paper, can be used as a model for developing other products aimed to improve nutrition of persons with healthy food preferences or diseases. In addition, it presents an opportunity for the food industry contribution to healthy lifestyle by developing products adapted to modern dietary recommendations and target consumers group
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