1,179 research outputs found

    The economics of ecosystem services of tree-based intercropping systems

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    Paper presented at the 13th North American Agroforesty Conference, which was held June 19-21, 2013 in Charlottetown, Prince Edward Island, Canada.In Poppy, L., Kort, J., Schroeder, B., Pollock, T., and Soolanayakanahally, R., eds. Agroforestry: Innovations in Agriculture. Proceedings, 13th North American Agroforestry Conference, Charlottetown, Prince Edward Island, Canada, June 19-21, 2013.The paper aims to determine the potential environmental benefits of multifunctional tree-based intercropping (TBI) systems. Here we evaluate ten ecosystem services using a mix of mathematical models for quantification and economic valuation. The results reveal a total annual margin of 2 558 CANha1y1.Theeconomicvalueofcombinednonmarketservicesis1634CAN ha-1y-1. The economic value of combined non-market services is 1 634 CAN ha-1y-1, which is higher than the value of marketable products (i.e. timber and agricultural products). The present value of the services for a rotation of 40 years is 54 782 CAN$ ha-1, about a third of which is contributed by agricultural products. Water quality regulation ranked highest among the non-market benefits followed by air quality maintenance, soil quality regulation, biological control, and pollination.Mahbubul Alam (1), Alain Olivier (1), Alain Paquette (2), J�rôme Dupras (3), Jean-Pierre Rev�ret (4) and Christian Messier (5) ; 1. D�partement de phytologie, Facult� des sciences de l'agriculture et de l'alimentation, Universit� Laval, Qu�bec City, G1V 0A6, Canada. 2. D�partement des sciences biologiques, Universit� du Qu�bec � Montr�al, Case postale 8888, Succursale Centre-ville, Montr�al, H3C 3P8, Canada. 3. D�partement de g�ographie, Universit� de Montr�al, Montr�al, Canada. 4. D�partement strat�gie, responsabilit� sociale et environnementale, Universit� du Qu�bec � Montr�al, Montr�al, Canada. 5. Institut des Sciences de la For�t temp�r�e (ISFORT), Universit� du Qu�bec en Outaouais, Ripon, JOV 1V0, QC, Canada.Includes bibliographical references

    Diversifying search in bee algorithms for numerical optimisation

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    © Springer Nature Switzerland AG 2018. Swarm intelligence offers useful instruments for developing collective behaviours to solve complex, ill-structured and large-scale problems. Efficiency in collective behaviours depends on how to harmonise the individual contributions so that a complementary collective effort can be achieved to offer a useful solution. The harmonisation helps blend diversification and intensification suitably towards efficient collective behaviours. In this study, two renown honeybees-inspired algorithms were analysed with respect to the balance of diversification and intensification and a hybrid algorithm is proposed to improve the efficiency accordingly. The proposed hybrid algorithm was tested with solving well-known highly dimensional numerical optimisation (benchmark) problems. Consequently, the proposed hybrid algorithm has demonstrated outperforming the two original bee algorithms in solving hard numerical optimisation benchmarks

    Molecular evidence for the presence of malaria vector species a of the Anopheles annularis complex in Sri Lanka

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    <p>Abstract</p> <p>Background</p> <p><it>Anopheles annularis s.l</it>. is a wide spread malaria vector in South and Southeast Asia, including Sri Lanka. The taxon <it>An. annularis </it>is a complex of two sibling species viz. A and B, that are differentiated by chromosome banding patterns and ribosomal gene sequences in India. Only species A is reported to be a malaria vector in India while the occurrence of sibling species in Sri Lanka has not been documented previously.</p> <p>Findings</p> <p>Anopheline larvae were collected at a site in the Jaffna district, which lies within the dry zone of Sri Lanka, and reared in the laboratory. Emerged adults were identified using standard keys. DNA sequences of the D3 domain of 28S ribosomal DNA (rDNA) and the internal transcribed spacer-2 (ITS-2) of the morphologically identified <it>An. annularis </it>were determined. BLASTn searches against corresponding <it>An. annularis </it>sequences in GenBank and construction of phylogenetic trees from D3 and ITS-2 rDNA sequences showed that the Sri Lankan specimens, and <it>An. annularis s.l</it>. specimens from several Southeast Asian countries were closely related to species A of the Indian <it>An. annularis </it>complex.</p> <p>Conclusions</p> <p>The results show the presence of the malaria vector <it>An. annularis </it>species A in Sri Lanka and Southeast Asia. Because <it>An. annularis </it>vectors have been long associated with malaria transmission in irrigated agricultural areas in the Sri Lankan dry zone, continued monitoring of <it>An. annularis </it>populations, and their sibling species status, in these areas need to be integral to malaria control and eradication efforts in the island.</p

    The Universal One-Loop Effective Action

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    We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.Comment: 30 pages, v2 contains additional comments and corrects typos, version accepted for publication in JHE

    Compliance with continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea among privately paying patients- a cross sectional study

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    Background: To evaluate the compliance, benefits and side effects associated with continuous positive airway pressure (CPAP) therapy among Pakistani patients treated for obstructive sleep apnea (OSA) in private sector.Methods: Patients diagnosed to have OSA based on overnight study who were recommended for CPAP therapy, between 1998 and 2003, were evaluated by telephonic survey and review of hospital notes. Compliance, benefits and side effects associated with CPAP therapy were assessed.Results: Out of 135 patients who were prescribed CPAP therapy, 75 could be contacted. Sixty (80%) started using CPAP within one month of diagnosis and 46 (61%) continued to use it long-term (beyond one year). Compliance with CPAP therapy was associated with higher body mass index, higher Epworth sleepiness scale score, history of witnessed apnea, and reduction in daytime sleepiness with CPAP therapy. OSA severity as assessed by apnea-hypopnea index did not affect compliance with CPAP therapy. Use of anti-depressants and CPAP induced sleep disturbances were associated with poor compliance with CPAP therapy.CONCLUSIONS: Obesity, excessive daytime sleepiness, witnessed apnea and improvement of daytime symptoms following use of CPAP were predictors of improved compliance. Use of antidepressants and CPAP induced sleep disturbances were predictors of poor compliance

    CP violation Beyond the MSSM: Baryogenesis and Electric Dipole Moments

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    We study electroweak baryogenesis and electric dipole moments in the presence of the two leading-order, non-renormalizable operators in the Higgs sector of the MSSM. Significant qualitative and quantitative differences from MSSM baryogenesis arise due to the presence of new CP-violating phases and to the relaxation of constraints on the supersymmetric spectrum (in particular, both stops can be light). We find: (1) spontaneous baryogenesis, driven by a change in the phase of the Higgs vevs across the bubble wall, becomes possible; (2) the top and stop CP-violating sources can become effective; (3) baryogenesis is viable in larger parts of parameter space, alleviating the well-known fine-tuning associated with MSSM baryogenesis. Nevertheless, electric dipole moments should be measured if experimental sensitivities are improved by about one order of magnitude.Comment: 33 pages, 6 figure

    The nature of fibrous dysplasia

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    Fibrous dysplasia has been regarded as a developmental skeletal disorder characterized by replacement of normal bone with benign cellular fibrous connective tissue. It has now become evident that fibrous dysplasia is a genetic disease caused by somatic activating mutation of the Gsα subunit of G protein-coupled receptor resulting in upregulation of cAMP. This leads to defects in differentiation of osteoblasts with subsequent production of abnormal bone in an abundant fibrous stroma. In addition there is an increased production of IL-6 by mutated stromal fibrous dysplastic cells that induce osteoclastic bone resorption
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