187 research outputs found

    Towering over Babel: Worlds Apart but Acting Together

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    In this paper we propose a new class of tests for the martingale difference hypothesis based on the moment conditions derived by Bierens (1982). In contrast with the existing consistent tests, the proposed test has a standard limiting distribution and is easy to implement. Comparing with the commonly used autocorrelation- and spectrum-based tests, it has power against a much larger class of alternatives that may be serially correlated or uncorrelated. Moreover, this test does not rely on the assumption of conditional homoskedasticity and requires a weaker moment condition. Our simulations confirm that the proposed test is powerful against various linear and nonlinear alternatives and is quite robust to the failure of higher-order moments. Our empirical study on exchange rate returns also shows that the conclusion resulted from the proposed test is different from that of the conventional tests.

    Compliance Strategies under Permits for Emissions

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73704/1/j.1937-5956.2007.tb00294.x.pd

    Product Design and Supply Chain Coordination Under Extended Producer Responsibility

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72335/1/j.1937-5956.2009.01018.x.pd

    An Approach to Integrating Environmental Considerations Within Managerial Decision-Making

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    Recent environmental trends, including (1) an expansion of existing command and control directives, (2) the introduction of market-based policy instruments, and (3) the adoption of extended producer responsibility, have created a need for new tools to help managerial decision-making. To address this need, we develop a nonlinear mathematical programming model from a profit-maximizing firm's perspective, which can be tailored as a decision-support tool for firms facing environmental goals and constraints. We typify our approach using the specific context of diesel engine manufacturing and remanufacturing. Our model constructs are based on detailed interviews with top managers from two leading competitors in the medium and heavy-duty diesel engine industry. The approach allows the incorporation of traditional operations-planning considerations—in particular, capacity, production, and inventory—together with environmental considerations that range from product design through production to product end of life. A current hurdle to implementing such a model is the availability of input data. We therefore highlight the need not only to involve all departments within businesses but also for industrial ecologists and business managers to work together to implement meaningful decision models that are based on accurate and timely data and can have positive economic and environmental impact.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79144/1/JIEC_243_sm_SuppMat.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/79144/2/j.1530-9290.2010.00243.x.pd

    Indian Ocean high-productivity event (10-8 Ma): linked to global cooling or to the initiation of the Indian monsoons?

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    Uplift of the Himalayas and Tibetan Plateau (ca. 10-8 Ma) has been said to be the main cause of the origin or intensification of the Indian monsoon system, because mountains modulate the land-sea thermal contrast. The intensification of the monsoons, in turn, is seen as the cause of major changes in fauna and flora on land (as a result of changing precipitation patterns) as well as in the Indian Ocean, where the monsoons drive increased upwelling and thus increased productivity. We argue that the interactions between the elevation of the Himalayas and Tibetan Plateau, the onset of the monsoons, and their effects on the Indian Ocean biota remain uncertain. The timing of these events (uplift, monsoons, and biotic change) is not well constrained. Neogene deep-sea benthic foraminiferal faunal and isotope records of the Ninetyeast Ridge combined with published data show that a major increase in biogenic productivity occurred at 10-8 Ma throughout the Indian Ocean, the equatorial Pacific, and southern Atlantic. We suggest that this Indian Ocean high-productivity event was not simply the result of monsoon-induced upwelling or nutrient delivery from the weathering of newly uplifted mountains, but may have been caused by strengthened wind regimes resulting from global cooling and the increase in volume of the Antarctic ice sheets

    ProInflam: a webserver for the prediction of proinflammatory antigenicity of peptides and proteins

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    Additional file 2: Table S2. Dipeptide composition distribution between proinflammatory and non proinflammatory data

    Engineered Microbes for Pigment Production Using Waste Biomass

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    Received: February 04, 2020; Revised: March 08, 2020; Accepted: March 16, 2020.Agri-food waste biomass is the most abundant organic waste and has high valorisation potential for sustainable bioproducts development. These wastes are not only recyclable in nature but are also rich sources of bioactive carbohydrates, peptides, pigments, polyphenols, vitamins, natural antioxidants, etc. Bioconversion of agri-food waste to value-added products is very important towards zero waste and circular economy concepts. To reduce the environmental burden, food researchers are seeking strategies to utilize this waste for microbial pigments production and further biotechnological exploitation in functional foods or value-added products. Microbes are valuable sources for a range of bioactive molecules, including microbial pigments production through fermentation and/or utilisation of waste. Here, we have reviewed some of the recent advancements made in important bioengineering technologies to develop engineered microbial systems for enhanced pigments production using agrifood wastes biomass/by-products as substrates in a sustainable way.MS, VKG and RB acknowledge ERA Chair for Food (By-) Products Valorization Technologies of the Estonian University of Life Sciences (VALORTECH) which has received funding from the European Union’s Horizon 2020 research and innovation program (under grant agreement No. 810630)

    FABRICATION AND TESTING OF HEMP FIBRE REINFORCED EPOXY COMPOSITES

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    Over the last decennium, composites of polymers reinforced with natural fibers have attracted field both from the academic world and from various industries. The most important of the natural fibers used in composite materials are flax, hemp, kenaf and sisal due to their properties and availability. Natural fibers based on cellulose have a low density, high stiffness and strong compared to those of glass fibers. For the automotive industry, where weight reduction always is an issue, this was said to be the original reason for the development of interior parts with natural fibers as fillers. The works evaluate study of mechanical behavior and develop a polymer matrix composite using hemp fiber by varying percentage weight fraction of hemp fibers by using hand lay-up method. The fabricated composite samples were trimmed according to the ASTM standards for different experiments and its characterization is performed

    Sustainable Phenylalanine-Derived SAILs for Solubilization of Polycyclic Aromatic Hydrocarbons

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    The solubilization capacity of a series of sustainable phenylalanine-derived surface-active ionic liquids (SAILs) was evaluated towards polycyclic aromatic hydrocarbons—naphthalene, anthracene and pyrene. The key physico-chemical parameters of the studied systems (critical micelle concentration, spectral properties, solubilization parameters) were determined, analyzed and compared with conventional cationic surfactant, CTABr. For all studied PAH solubilization capacity increases with extension of alkyl chain length of PyPheOCn SAILs reaching the values comparable to CTABr for SAILs with n = 10–12. A remarkable advantage of the phenylalanine-derived SAILs PyPheOCn and PyPheNHCn is a possibility to cleave enzymatically ester and/or amide bonds under mild conditions, to separate polycyclic aromatic hydrocarbons in situ. A series of immobilized enzymes was tested to determine the most suitable candidates for tunable decomposition of SAILs. The decomposition pathway could be adjusted depending on the choice of the enzyme system, reaction conditions, and selection of SAILs type. The evaluated systems can provide selective cleavage of the ester and amide bond and help to choose the optimal decomposition method of SAILs for enzymatic recycling of SAILs transformation products or as a pretreatment towards biological mineralization. The concept of a possible practical application of studied systems for PAHs solubilization/separation was also discussed focusing on sustainability and a green chemistry approach

    Prediction of IL4 Inducing Peptides

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    The secretion of Interleukin-4 (IL4) is the characteristic of T-helper 2 responses. IL4 is a cytokine produced by CD4+ T cells in response to helminthes and other extracellular parasites. It has a critical role in guiding antibody class switching, hematopoiesis and inflammation, and the development of appropriate effector T-cell responses. In this study, it is the first time an attempt has been made to understand whether it is possible to predict IL4 inducing peptides. The data set used in this study comprises 904 experimentally validated IL4 inducing and 742 noninducing MHC class II binders. Our analysis revealed that certain types of residues are preferred at certain positions in IL4 inducing peptides. It was also observed that IL4 inducing and noninducing epitopes differ in compositional and motif pattern. Based on our analysis we developed classification models where the hybrid method of amino acid pairs and motif information performed the best with maximum accuracy of 75.76% and MCC of 0.51. These results indicate that it is possible to predict IL4 inducing peptides with reasonable precession. These models would be useful in designing the peptides that may induce desired Th2 response
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