3,108 research outputs found
Simulating with RICE Coalitionally Stable Burden Sharing Agreements for the Climate Change Problem
In this paper we test empirically with the Nordhaus and Yang (1996) RICE model the core property of the transfer scheme adv ocated by Germain, Toint and Tulkens (1997). This scheme is designed to sustain full cooperation in a voluntary international environmental agreement by making all countries at least as well off as they would be by joining coalitions adopting emission abatement policies that maximize their coalition payoff; under the scheme no individual country, nor any subset of countries would have an interest in leaving the international environmental agreement. The simulations show that the transfer scheme yields an allocation in the core of the carbon emission abatement game associated with the RICE model. Finally, we discuss some practical implications of the transfer scheme for current climate negotiations.Environmental economics, climate change, burden sharing, simulations, core of cooperative games
Finished Genome Sequences of Xanthomonas fragariae, the Cause of Bacterial Angular Leaf Spot of Strawberry.
Xanthomonas fragariae is a foliar pathogen of strawberry that is of significant concern to nursery production of strawberry transplants and field production of strawberry fruit. Long-read sequencing was employed to generate finished genomes for two isolates (each with one chromosome and two plasmids) from symptomatic plants in northern California
Inhibition of Xanthomonas fragariae, Causative Agent of Angular Leaf Spot of Strawberry, through Iron Deprivation.
In commercial production settings, few options exist to prevent or treat angular leaf spot (ALS) of strawberry, a disease of economic importance and caused by the bacterial pathogen Xanthomonas fragariae. In the process of isolating and identifying X. fragariae bacteria from symptomatic plants, we observed growth inhibition of X. fragariae by bacterial isolates from the same leaf macerates. Identified as species of Pseudomonas and Rhizobium, these isolates were confirmed to suppress growth of X. fragariae in agar overlay plates and in microtiter plate cultures, as did our reference strain Pseudomonas putida KT2440. Screening of a transposon mutant library of KT2440 revealed that disruption of the biosynthetic pathway for the siderophore pyoverdine resulted in complete loss of X. fragariae antagonism, suggesting iron competition as a mode of action. Antagonism could be replicated on plate and in culture by addition of purified pyoverdine or by addition of the chelating agents tannic acid and dipyridyl, while supplementing the medium with iron negated the inhibitory effects of pyoverdine, tannic acid and dipyridyl. When co-inoculated with tannic acid onto strawberry plants, X. fragariae's ability to cause foliar symptoms was greatly reduced, suggesting a possible opportunity for iron-based management of ALS. We discuss our findings in the context of 'nutritional immunity,' the idea that plant hosts restrict pathogen access to iron, either directly, or indirectly through their associated microbiota
The physician-scientists: rare species in Africa
There is paucity of physician-scientists in Africa, resulting in overt dependence of clinical practice on research findings from advanced "first world"
countries. Physician-scientists include individuals with a medical degree alone or combined with other advanced degrees (e.g. MD/MBChB and PhD)
with a career path in biomedical/ translational and patient-oriented/evaluative science research. The paucity of clinically trained research scientists
in Africa could result in dire consequences as exemplified in the recent Ebola virus epidemic in West Africa, where shortage of skilled clinical
scientists, played a major role in disease progression and mortality. Here we contextualise the role of physician-scientist in health care
management, highlight factors limiting the training of physician-scientist in Africa and proffer implementable recommendations to address these
factors
Subregion graph: A path planning acceleration structure for characters with various motion types in very large environments
Modern computer graphics applications commonly feature very large virtual environments and diverse characters which perform different kinds of motions. To accelerate path planning in such a scenario, we propose the subregion graph data structure. It consists of subregions, which are clusters of locally connected waypoints inside a region, as well as subregion connectivities. We also present a fast algorithm to automatically generate a subregion graph from an enhanced waypoint graph map representation, which also supports various motion types and can be created from large virtual environments. Nevertheless, a subregion graph can be generated from any graphbased map representation. Our experiments show that a subregion graph is very compact relative to the input waypoint graph. By firstly planning a subregion path, and then limiting waypoint-level planning to this subregion path, over 8 times average speedup can be achieved, while average length ratios remain as low as 102.5%
The societal impact of governmental voluntary sustainable development programs: Case "the Commitment 2050"
This thesis aims at understanding the content and potential societal impact of governmental voluntary sustainable development program through a case entity "The Finland we want by 2050 - Society's commitment to sustainable development", focusing on business participants. Existing literature has focused mostly on evaluating issue or industry specific voluntary environmental or social programs. However, all-encompassing governmental voluntary programs that are open for all societal actors and cover all sustainability aspects are a new phenomenon that set a new ground for research.
The research is an evaluative single case study that combines both qualitative and quantitative data and analysis methods. The primary data is collected from the program's database containing 170 individual commitments out of which 42 were company commitments. The research is complemented by official documents and interviews with three company representatives, two representatives of the FNCSD and one third party representative. Individual operative commitments were analysed using an evaluation matrix.
The findings in the study points out that the program is most likely to cause positive impact on society. However, due to insufficient information provided by the participants, the absolute impact couldn't be measured. Majority of the participants used internally measurable indicators that could not be used for evaluating societal impact. This lead to suggestion that voluntary programs should have better indicators in order to measure societal impact.
The study also showed that one third of the commitments did not have any impact through the program. This was caused by two types of commitments: those that existed before the participant joined the program and those that pledged to carry on business-as-usual activities as their commitment. In addition, the participants interpreted some of the program criteria and objectives differently. This caused variation in quality and difficulties for evaluating the impact of the program. The suggestion is that criteria for participants should be clearer in order to avoid openness for interpretation.
The commitment 2050 proved capabilities in attracting SMEs to take public CSR actions instead of only including large companies that are traditionally more visible in CSR. Nevertheless, the commitment program attracted mostly companies that were already active in the field of CSR or sustainable development
Hubungan Penarikan Karyawan Terhadap Produktivitas Kerja Karyawan PT.Frisian Flag Indonesia Medan
Karyawan adalah asset utama perusahaan yang menjadi perencana dan
pelaku aktif dari setiap aktivitas perusahaan. Perkembangao suatu perusahaan serta semakin tingginya teknologi yang digunakan menyebabkan sering terjadinya perubahan serta semakin meluasnya pekerjaan yang akan diemban oleh karyawan, sehingga perlu diadakan pengembangan karyawan. Pengembangan karyawan bertujuan untuk meningkat.kan kemampuan teknis, teoritis, konseptual dan moral karyawan supaya prestasi kedanya baik dao mencapai nasil yang optimal. Adapun tujuan penelitian ini adalah guna mengetahui dan menganalisis pengaruh positif dan signifikan pengembangan karyawan (pelatihan, mutasi dan promosi) terhadap prestasi kerja pada PT. Frisian Flag Indonesia Medan. Rumusan masalah dari penelitian adalah untuk mengetahui apakah variable pengembangan karyawan
(pelatihan, mutasi dan prormosi) berpengaruh positif dan signifikan terhadap prestasi kerja karyawan pada PT. Frisian Flag Indonesia Medan
Transdisciplinary systems research to develop a holistic approach to reduce the spread and impact of cocoa swollen shoot virus disease in Ghana (TransdisCSSVD)
West Africa is the world’s most important cocoa (Theobroma cacao L.) growing region. The Cocoa Swollen Shoot Virus Disease (CSSVD) is one of the major productivity limitations, particularly in Ghana. Some 800’000 farm families’ livelihoods depend on revenues from the crop in Ghana alone. The only measure to treat CSSVD is to cut out infected trees. The national eradication program, implemented by the Ghanaian government since 1946, has cut out more than 250 million trees until today. Despite these efforts, CSSVD is still prevalent in the field. Research has tried to contribute to CSSVD control through breeding for resistant varieties, as well as investigating the effects of barriers with immune crops and protection through a “vaccination” with the mild virus strain N1. Despite the promising nature of the results from these research activities, they have seen limited application in the field. Therefore, a shift in approaches is needed: farmers, extension agents and other relevant stakeholders need to be involved in planning and execution of future interventions from the very beginning of project life cycles.
We are starting a project called “TransdisCSSVD” in Ghana, which approaches disease control by capitalizing on the farmers’ perspective on CSSVD control in order to identify the main bottlenecks for implementation of available CSSVD control options. Furthermore, an in-depth study on diversification of cocoa production systems (e.g. agroforestry; fragmentation of landscapes by barriers of non-host crops, shrubs or trees; etc.) will fill an important knowledge gap with regard to CSSVD regulation. The expected results may provide crucial insights for policy makers about meaningful ways of adapting the existing CSSVD prevention and control program. For that purpose, transdisciplinary workshops with policymakers are planned. More dissemination activities such as farmer field days and exchange workshops aim at stimulating the implementation of research results on the ground
Predicting First Traversal Times for Virions and Nanoparticles in Mucus with Slowed Diffusion
AbstractParticle-tracking experiments focusing on virions or nanoparticles in mucus have measured mean-square displacements and reported diffusion coefficients that are orders of magnitude smaller than the diffusion coefficients of such particles in water. Accurate description of this subdiffusion is important to properly estimate the likelihood of virions traversing the mucus boundary layer and infecting cells in the epithelium. However, there are several candidate models for diffusion that can fit experimental measurements of mean-square displacements. We show that these models yield very different estimates for the time taken for subdiffusive virions to traverse through a mucus layer. We explain why fits of subdiffusive mean-square displacements to standard diffusion models may be misleading. Relevant to human immunodeficiency virus infection, using computational methods for fractional subdiffusion, we show that subdiffusion in normal acidic mucus provides a more effective barrier against infection than previously thought. By contrast, the neutralization of the mucus by alkaline semen, after sexual intercourse, allows virions to cross the mucus layer and reach the epithelium in a short timeframe. The computed barrier protection from fractional subdiffusion is some orders of magnitude greater than that derived by fitting standard models of diffusion to subdiffusive data
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