8,108 research outputs found
Análisis del artículo 207-2 del estatuto tributario nacional el cual creó nuevas rentas exentas y su incidencia en las finanzas del estado
La inquietud por saber si el estado está cumpliendo los objetivos en sus finanzas, otorgando beneficios tributarios a diferentes sectores de la economía, tales como el sector hotelero, el sector agrícola primario, el sector energético, entre otros, a generado inquietud para analizar el articulo 207-2 de Estatuto Tributario Nacional, el cual creo nuevas rentas exentas desde el año 2002 con la expedición de la ley 788 de 2002. El objetivo es determinar si dichas exenciones en el impuesto sobre la renta y complementarios, compensan dentro del Presupuesto General de la Nación, los ingresos que deja de percibir el Estado al otorgar dichos beneficios tributariosThe restlessness to know if the State is fulfilling the objectives in its finances, granting tributary benefits to different sectors from the economy, such as the hotel sector, the primary sector agricultural, the power sector, among others, to generated restlessness to analyze article 207-2 of National Statute Tributary, which I create new rents free from year 2002 with the expedition of 2002 law 788. The objective is to determine if these exemptions in the tax on the rent and complementary, compensate within the General Budget of the Nation, the income that stop perceiving the State when granting these tributary benefit
Infections with extracellular trypanosomes require control by efficient innate immune mechanisms and can result in the destruction of the mammalian humoral immune system
Salivarian trypanosomes are extracellular parasites that affect humans, livestock, and game animals around the world. Through co-evolution with the mammalian immune system, trypanosomes have developed defense mechanisms that allow them to thrive in blood, lymphoid vessels, and tissue environments such as the brain, the fat tissue, and testes. Trypanosomes have developed ways to circumvent antibody-mediated killing and block the activation of the lytic arm of the complement pathway. Hence, this makes the innate immune control of the infection a crucial part of the host-parasite interaction, determining infection susceptibility, and parasitemia control. Indeed, trypanosomes use a combination of several independent mechanisms to avoid clearance by the humoral immune system. First, perpetuated antigenic variation of the surface coat allows to escape antibody-mediated elimination. Secondly, when antibodies bind to the coat, they are efficiently transported toward the endocytosis pathway, where they are removed from the coat proteins. Finally, trypanosomes engage in the active destruction of the mammalian humoral immune response. This provides them with a rescue solution in case antigenic variation does not confer total immunological invisibility. Both antigenic variation and B cell destruction pose significant hurdles for the development of anti-trypanosome vaccine strategies. However, developing total immune escape capacity and unlimited growth capabilities within a mammalian host is not beneficial for any parasite, as it will result in the accelerated death of the host itself. Hence, trypanosomes have acquired a system of quorum sensing that results in density-dependent population growth arrest in order to prevent overpopulating the host. The same system could possibly sense the infection-associated host tissue damage resulting from inflammatory innate immune responses, in which case the quorum sensing serves to prevent excessive immunopathology and as such also promotes host survival. In order to put these concepts together, this review summarizes current knowledge on the interaction between trypanosomes and the mammalian innate immune system, the mechanisms involved in population growth regulation, antigenic variation and the immuno-destructive effect of trypanosomes on the humoral immune system. Vaccine trials and a discussion on the role of innate immune modulation in these trials are discussed at the end
Campaña de mercadeo social "educando con agua" en beneficiencia sobre la educación de derechos
In this research project, two entities, the company Thessaly Spring CO and women's association Nela Martínez, come together to collaborate, teach and sponsor several schools blended together in Machachi community. In this way, both organizations expose their social responsibility and contribution to the community, through a campaign that educates about rights.En este proyecto de investigación, dos entidades, la empresa Tesalia Spring C.O. y La asociación de mujeres Nela Martínez, se unen para colaborar, enseñar y patrocinar a varias escuelas compenetradas en la comunidad de Machachi. De esta forma, ambas organizaciones exponen su responsabilidad social y aporte con la comunidad, a través de una campaña que educa sobre derechos
Empowerment and sustainability to promove a dynamic, thoughtful, and inventive community: the case of green meetings at Casablanca Marriott Hotel
The case offers students an opportunity to understand the importance of an empowered workforce
to implement Marriott’s social and sustainable values during the process of rebranding and
renovation of Casablanca Marriott hotel. The case study’s purpose is to pinpoint the significance
of HRM practices in shaping employees’ performance, augmenting their engagement and
adherence to sustainable practices. The hospitality industry plays a determinant role by training its
employees and also by enhancing the communication with internal and external stakeholders in
order to build a conscious community where initiatives such as Green Meetings are incentivized
Gestion durable des ressources dans la chaîne de valeur européenne de l’acier
The present thesis delved into the current and future interactions within the European Steel Industry and of it with the environment it is a part of, with the main objective of supporting decision- and policy-making efforts oriented towards sustainability and circularity, helping to shape the future of steel in the European Community. The thesis used the European Steel Industry as a case study to explore the potential benefits of integrating Life Cycle Assessment (LCA) into System Dynamics (SD) under the scopes of Circular Economy and Industrial Ecology. A model representative of the European Steel Industry was built modularly in Stella Architect, following ILCD and ISO guidelines and standards for LCA. Throughout 4 of the 5 articles developed for the present thesis, 21 simulation runs were performed on the aforementioned model: 12 on identifying potential constraints and benefits of End-of-Life policies; 5 assessing the advantages and disadvantages of different Supply Chain Integration (SCI) strategies along European steel supply chains; and 4 addressing the interactions between biophysical and economic dynamics in the steel market. An additional article was developed using the methodologies of Circles of Sustainability and Sustainable Urban Metabolism to appraise the challenges and contributions of steel as part of servitization initiatives in urban environments. Overall results indicated that integrating LCA into SD was not only feasible and capable of reproducing results, trends and behaviors from previous scientific studies, but also of contributing to both methodologies in different levels. This approach has potential to interest policy-makers who seek more granularity within the European Steel Industry as well as decision-makers searching for a broader understanding of their operation’s dynamics beyond the gates, notably regarding raw material scarcity, resource self-sufficiency, and resource ownership retention. From the results of each article it was observed that, (a) pushing for recycling and reuse could generate interesting medium- to long-term results for circularity, transitioning away from fossil fuels and developing a whole new market around end-of-life services; (b) different SCI approaches can be environmentally and strategically promising; (c) six key biophysical variables can distinctively affect spot prices, future prices, EBITDA margins, capacity utilization, dividend payouts, and costs of steelmaking; and (d) servitization can provide significant benefits to sustainable cities, while also being able to substantially alter the supply-side dynamics of steelmaking, highlighting how important it is for steelmakers to pay close attention to the service-providing initiatives that may concern their clients and products.La présente thèse entend examiner les interactions présentes et futures entre l'industrie sidérurgique européenne et son environnement, avec pour objectifs principaux, l’amélioration de la prise de décision et l'élaboration de politiques industrielles en matière de durabilité et de circularité. La thèse contribue à l’émergence de propositions contribuant à façonner l'avenir de l'acier dans l’Union Européenne. L'industrie sidérurgique européenne est utilisée ici comme un cas d’école, visant à explorer les avantages potentiels pour l’économie circulaire et l’écologie industrielle, d’une intégration d’un outil (Analyse du Cycle de Vie – ACV) dans une méthodologie (Dynamique des Systèmes – SD). Un modèle modulaire pour l’industrie sidérurgique européenne a été construit et, pour 4 des 5 articles développés dans la thèse, 21 simulations ont été effectuées. 12 simulations ont permis d’identifier les contraintes potentielles et les avantages des stratégies de fin de vie; 5 d’évaluer les avantages et les inconvénients des différentes stratégies d’intégration de la chaîne d’approvisionnement (SCI) dans la filière européenne de l’acier; et 4 de traiter des interactions entre les dynamiques biophysiques et économiques sur le marché de l'acier. Le dernier article s’appuie sur une nouvelle méthodologie – les Cercles de Durabilité et le Métabolisme Urbain Durable – pour évaluer les défis et les contributions de l'acier dans le cadre de l’éco-fonctionnalité en milieu urbain. Les résultats ont montré que l’intégration de l’ACV dans les stratégies de développement durable permettait de reproduire assez fidèlement les résultats et les scénarios d’études scientifiques antérieures, tout en suggérant des apports méthodologiques relativement novateurs. Cette recherche opérationnelle est susceptible d'intéresser les managers et des chefs d’entreprises qui s’attachent aux questions d’efficience et de résilience de l’outil industriel, ainsi que les décideurs politiques qui souhaitent cerner les enjeux d’une pénurie de matières premières ou d’une politique de recyclage de l’acier à l’échelle européenne. D'après les résultats de chaque article, il a été observé que (a) le recyclage et la réutilisation pourraient générer des résultats intéressants à moyen et à long terme en matière de circularité, en abandonnant notamment les combustibles fossiles et en développant un tout nouveau marché autour des services de fin de vie; (b) différentes approches en matière de chaine logistique intégrée semblent être prometteuses d'un point de vue environnemental et stratégique; (c) six variables biophysiques clés peuvent avoir une incidence notoire sur les cours au comptant, les cours à terme, les marges d'EBITDA, l'utilisation des capacités de production, la distribution des dividendes et les coûts de fabrication de l'acier; et (d) la dynamique servicielle dans le cadre de l’éco-fonctionnalité peut apporter des avantages significatifs aux villes durables, tout en modifiant considérablement la structure de l’offre sur le marché de l’acier
Validation of the Lower Tagus Valley velocity and structural model using ambient noise broadband measurements
Along his history the Lower Tagus Valley (LTV) region was shaken by several earthquakes, some of them were
produced in large ruptures of offshore structures located southwest of the Portuguese coastline, among these we
the Lisbon earthquake of 1 November 1755; other moderates earthquakes were produced by local sources such as
the 1344, 1531 and the 1909 Benavente earthquake.
In order to promote an improved assessment of the seismic hazard in this region, we propose the introduction
of realistic methods on the prediction of ground motion produced by moderate to large earthquakes in LTV.
This process involves the establishment of a structural 3D model based on all the available geophysical and
geotechnical data on the area (seismic, gravimetric, deep wells and geological outcrops) and the determination of
wave propagation from a finite difference method: by applying the E3D program [1,2].
To confirm this model we use broadband ambient noise measurements collected in two profiles with azimuth
perpendicular to the basin axis and we applied the horizontal to vertical (H/V) spectral ratio method [3] to the
recordings in order to estimate the amplification of the basin. The H/V curves obtained reveals the existence of two
low frequency peaks centered on 0.2 a 1 Hz frequencies[4]. These peaks are strongly related with the thickness
of Cenozoic and alluvial sediments. By inversion of the H/V curve, we obtain a more detailed velocity model for
the region where the profile were determined, which is in good agreement with borehole data and other results
obtained with magnetic and seismic reflection methods
Rating and perceived helpfulness in a bipartite network of online product reviews
In many e-commerce platforms user communities share product information in the
form of reviews and ratings to help other consumers to make their choices. This
study develops a new theoretical framework generating a bipartite network of products
sold by Amazon.com in the category “musical instruments”, by linking products
through the reviews. We analyze product rating and perceived helpfulness of
online customer reviews and the relationship between the centrality of reviews, product
rating and the helpfulness of reviews using Clustering, regression trees, and random
forests algorithms to, respectively, classify and find patterns in 2214 reviews.
Results demonstrate: (1) that a high number of reviews do not imply a high product
rating; (2) when reviews are helpful for consumer decision-making we observe an
increase on the number of reviews; (3) a clear positive relationship between product
rating and helpfulness of the reviews; and (4) a weak relationship between the centrality
measures (betweenness and eigenvector) giving the importance of the product
in the network, and the quality measures (product rating and helpfulness of reviews)
regarding musical instruments. These results suggest that products may be central to
the network, although with low ratings and with reviews providing little helpfulness
to consumers. The findings in this study provide several important contributions for
e-commerce businesses’ improvement of the review service management to support
customers’ experiences and online customers’ decision-making.publishe
Development of a recombinase polymerase amplification lateral flow assay for the detection of active Trypanosoma evansi infections
Author summary
Neglected tropical diseases (NTDs) affecting humans and/or domestic animals severely impair the socio-economic development of endemic areas. One of these diseases, animal trypanosomosis, affects livestock and is caused by the parasites of the Trypanosoma genus. The most widespread causative agent of animal trypanosomosis is T. evansi, which is found in large parts of the world (Africa, Asia, South America, Middle East, and the Mediterranean). Proper control and treatment of the disease requires the availability of reliable and sensitive diagnostic tools. DNA-based detection techniques are powerful and versatile in the sense that they can be tailored to achieve a high specificity and usually allow the reliable detection of low amounts of parasite genetic material. However, many DNA-based methodologies (such as PCR) require trained staff and well-equipped laboratories, which is why the research community has actively investigated in developing amplification strategies that are simple, fast, cost-effective and are suitable for use in minimally equipped laboratories and field settings. In this paper, we describe the development of a diagnostic test under a dipstick format for the specific detection of T. evansi, based on a DNA amplification principle (Recombinase Polymerase Amplification aka RPA) that meets the above-mentioned criteria.
Background
Animal trypanosomosis caused by Trypanosoma evansi is known as "surra" and is a widespread neglected tropical disease affecting wild and domestic animals mainly in South America, the Middle East, North Africa and Asia. An essential necessity for T. evansi infection control is the availability of reliable and sensitive diagnostic tools. While DNA-based PCR detection techniques meet these criteria, most of them require well-trained and experienced users as well as a laboratory environment allowing correct protocol execution. As an alternative, we developed a recombinase polymerase amplification (RPA) test for Type A T. evansi. The technology uses an isothermal nucleic acid amplification approach that is simple, fast, cost-effective and is suitable for use in minimally equipped laboratories and even field settings.
Methodology/Principle findings
An RPA assay targeting the T. evansi RoTat1.2 VSG gene was designed for the DNA-based detection of T. evansi. Comparing post-amplification visualization by agarose gel electrophoresis and a lateral flow (LF) format reveals that the latter displays a higher sensitivity. The RPA-LF assay is specific for RoTat1.2-expressing strains of T. evansi as it does not detect the genomic DNA of other trypanosomatids. Finally, experimental mouse infection trials demonstrate that the T. evansi specific RPA-LF can be employed as a test-of-cure tool
Current state of the Prunetalia spinosae communities in the centre and south of the Iberian Peninsula (Spain, Portugal)
This paper re-examines the Rhamno-Prunetea class in the centre and south of the Iberian Peninsula, especially
in Andalusia. The paper also deals with the alliances Pruno-Rubion ulmifolii Lonicero-Berberidion hispanicae in the
south of the Iberian Peninsula, and Berberidion vulgaris (Berberidenion seroi) in the area of Cuenca. Our analysis of
225 relevés arranged in 22 phytosociological tables helped us to re-organize the available information and subsequently
propose three associations and two subassociations: Clematido vitalbae-Rosetum micranthae nova; Berberido hispanicae-
Buxetum sempervirentis nova; Roso siculae-Berberidetum hispanicae Mota nova subas. prunetosum ramburii Mota
nova; Lonicero arboreae-Rhamnetum cathartici Martínez-Parras and Molero 1983 subas. prunetosum ranburii nova. As
a result of the study, a total of 18 syntaxa with the rank of association and four with the rank of subassociation are proposed
for the south of the Iberian Peninsula
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