237 research outputs found
Reflexiones sobre el cumplimiento de la tregua entre maras en El Salvador
In March 2012, the biggest and most powerful gangs in El Salvador,
«maras» Salvatrucha and Dieciocho, called a truce and decided to «calm down» (calmarse). In order to reduce the high levels of violence that affect society as a whole, the heads of both maras committed themselves
to stop the killings, kidnappings and blackmail that had been occurring in almost every corner of El Salvador for more than two decades. However, over the last few months there is some evidence that seems to indicate that the purposes of implementing the truce were not those that han been expressed by the maras, and were closely linked with
drug trafficking in the country. In spite of the Organization of American
States' (OAS) approval and its role of guarantor of the peacebulding process, the truce is in the maras' hands and not in those of the civil society, wich is still reluctant to trust these organizations. In this scenario,
policymakers should change the status quo, particularly in view of the coming presidential elections.En marzo del año 2012, las dos maras más poderosas y numerosas de El Salvador, la mara Salvatrucha y la mara Dieciocho establecieron una tregua entre ellas y decidieron calmarse. Con el fin de reducir los niveles de violencia que afectaba a la sociedad en general, sus más altas cúpulas se comprometieron a parar los asesinatos, secuestros y extorsiones que tenían lugar en casi todos los rincones del país desde hacía más de dos décadas. Sin embargo, en los últimos meses han aparecido algunos elementos que parecen indicar que los objetivos de la implentaciópn de la tregua eran otros, íntimamente vinculados a los negocios del narcotráfico en territorio salvadoreño. A pesar del beneplácito de la Organización de los Estados Americanos (OEA) y de su rol como garante del proceso de pacificación, la tregua está en manos de las maras más que de la socidedad civil, que desconfía de ella. En este contexto, correspondería a la clase política modificar el statu quo, en especial considerando la proximidad de las elecciones presidenciales
Correction: Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes
Widespread evidence for horizontal transfer of transposable elements across Drosophila genomes
A genome-wide comparison of transposable elements reveals evidence for unexpectedly high rates of horizontal transfer between three species of Drosophil
Seguridad y violencia en el actual escenario latinoamericano: de la teoría a la praxis
De acuerdo con el informe global de homicidios de Naciones Unidas (2011), América Latina es actualmente el continente más violento del mundo. Esa violencia, no es homogénea y su incremento obedece en gran medida a los cambios que sufrió el escenario de seguridad internacional en general y latinoamericana en particular. Es por eso que se hace necesario diferenciar los tipos de violencia existentes en distintas sociedades, así como el impacto que su presencia tiene sobre la ciudadanía.Como resultado, llama la atención que aquellos países con los indicadores más altos en términos de violencia objetiva, presentan tasas de violencia subjetiva sugerentemente bajas. Sin duda este fenómeno se debe a las características culturales de cada país pero también a la naturaleza de la violencia y a su vínculo con la criminalidad organizada.According to the United Nation´s Global Study on Homicides (2011), Latin America is currently the world´s most violent continent. Such violence is not homogeneous and its increase is related to the changes suffered by the international security scenario in general and particularly in Latin America. Thus, is necessary to differentiate the violence that exists in different societies as well as the impact their presence has in the citizenship. As a result, it is noteworthy that those countries with the highest indicators in terms of objective violence suggestively presents low rates related to subjective violence. There is no doubt that this phenomenon is due to each country´s cultural characteristics but also to the nature of violence and its links with criminal organizations.Instituto de Relaciones Internacionale
Epidemiological study of honeybee pathogens in Europe: The results of Castilla-La Mancha (Spain)
As a part of a Pilot Monitoring Program of honey bee health coordinated by the EURL (European Union Reference Laboratory) and according to the criteria established for Spain, 14 apiaries in Castilla-La Mancha were selected at random and sampled during the autumns of 2012-2014 to identify the most prevalent nosogenic agents, potentially those related to the honey bee colony collapse phenomenon. In all the apiaries studied, Nosema ceranae was the most prevalent pathogen detected over the three years, confirming the worldwide spread of this microsporidian, a pathogen that negatively affects honey bee health at an individual and colony level. Trypanosomatids were also very prevalent in honey bee colonies, although the majority of Trypanosomatids detected were not Crithidia mellificae but rather the genetically distinct Lotmaria passim lineage. We also detected Varroa destructor mites, and the particularly high prevalence in 2014 suggests a possible problem regarding mite control in field conditions that requires attention. In agreement with data from other regions, the BQCV and DWV were the most prevalent viruses in honey bee colonies and thus, the Varroa-DVW interaction may be an important cause of bee colony mortality. While there was little evidence of a relationship between the BQCV virus and N. ceranae under field conditions during 2012, this was not the case in 2013 and 2014. Finally, the AKI-complex or LSV-complex was not detected. The information obtained in this study should help orientate future plans for honey bee disease control
Frequent parasitism of Apis mellifera by trypanosomatids in geographically isolated areas with restricted beekeeping movements
Trypanosomatids form a group of high prevalence protozoa that parasitise honey bees, with Lotmaria passim as the
predominant species worldwide. However, the knowledge about the ecology of trypanosomatids in isolated areas is
limited. The Portuguese archipelagos of Madeira and Azores provide an interesting setting to investigate these
parasites because of their geographic isolation, and because they harbour honey bee populations devoid of two major
enemies: Varroa destructor and Nosema ceranae. Hence, a total of 661 honey bee colonies from Madeira and the
Azores were analysed using different molecular techniques, through which we found a high prevalence of
trypanosomatids despite the isolation of these islands. L. passim was the predominant species and, in most colonies,
was the only one found, even on islands free of V. destructor and/or N. ceranae with severe restrictions on colony
movements to prevent the spread of them. However, islands with V. destructor had a significantly higher prevalence
of L. passim and, conversely, islands with N. ceranae had a significantly lower prevalence of the trypanosomatid.
Crithidia bombi was detected in Madeira and on three islands of the Azores, almost always coincident with L. passim.
By contrast, Crithidia mellificae was not detected in any sample. A High-Throughput Sequencing analysis distinguished
two main haplotypes of L. passim, which accounted for 98% of the total sequence reads. This work suggests that L.
passim and C. bombi are parasites that have been associated with honey bees predating the spread of V. destructor
and N. ceranae.This work was funded by the Consejería de Educación, Cultura y Deportes, of the Junta de Castilla – La Mancha
(European Regional development Fund) project No. SBPLY/19/180501/000334 and through the program COMPETE
2020—POCI (Programa Operacional para a Competividade e Internacionalização) and FCT (Fundação para a Ciência e
a Tecnologia) in the framework of the project BeeHappy (POCI-01-0145-FEDER-029871).info:eu-repo/semantics/publishedVersio
Effectiveness of electric harps in reducing Vespa velutina predation pressure and consequences for honey bee colony development
BACKGROUND: Vespa velutinahas become a species of concern in invaded regions of Europe and Asia, due to its impacts onbiodiversity, apiculture and society. This hornet, a ferocious hunter of pollinating insects, poses a serious threat to biodiversityand pollination services. Despite ongoing efforts, its extermination in continental Europe is hampered by a lack of effective con-trol methods, thus effective mitigation measures are primary concerns. The aims of this work were: (i) to study the effects of V. velutina predating on honey bee colonies, and (ii) to assess the effectiveness of electric harps in reducing hunting pressureand predation. We assessed the predation pressure and compared honey bee colony performance, body weight of workers, andwinter survivorship for protectedversusunprotected colonies in 36 experimental hives across three apiaries.
RESULTS: Electric harps protected honey bees by reducing predation pressure and therefore mitigating foraging paralysis. Consequently, foraging activity, pollen income, brood production and worker body weight were higher in protected colonies whichin turn showed greater winter survivorship than those that were unprotected, especially at sites with intermediate to highlevels of predation.
CONCLUSION: The predation of V. velutina affects foraging activity, breeding, body weight and colony survivorship of Apis mellifera. Electric harps contribute significantly to mitigate the impact of this invasive hornet on apiaries; however, they should bedeployed in tandem with additional measures to preserve honey bee colony stocks, such as facilitating access to food sourcesfor colonies during the periods of highest predation pressure.Programa Interreg Atlantic Area (Fondo Europeo de Desarrollo Regional, Unión Europea) | Ref. EAPA_800/2018–Atlantic-PositiveUniversidade de Vigo/CISU
Population Genetics of Nosema apis and Nosema ceranae: One Host (Apis mellifera) and Two Different Histories
Two microsporidians are known to infect honey bees: Nosema apis and Nosema ceranae. Whereas population genetics data for the latter have been released in the last few years, such information is still missing for N. apis. Here we analyze the patterns of nucleotide polymorphism at three single-copy loci (PTP2, PTP3 and RPB1) in a collection of Apis mellifera isolates from all over the world, naturally infected either with N. apis (N = 22) or N. ceranae (N = 23), to provide new insights into the genetic diversity, demography and evolution of N. apis, as well as to compare them with evidence from N. ceranae. Neutral variation in N. apis and N. ceranae is of the order of 1%. This amount of diversity suggests that there is no substantial differentiation between the genetic content of the two nuclei present in these parasites, and evidence for genetic recombination provides a putative mechanism for the flow of genetic information between chromosomes. The analysis of the frequency spectrum of neutral variants reveals a significant surplus of low frequency variants, particularly in N. ceranae, and suggests that the populations of the two pathogens are not in mutation-drift equilibrium and that they have experienced a population expansion. Most of the variation in both species occurs within honey bee colonies (between 62%-90% of the total genetic variance), although in N. apis there is evidence for differentiation between parasites isolated from distinct A. mellifera lineages (20%-34% of the total variance), specifically between those collected from lineages A and C (or M). This scenario is consistent with a long-term host-parasite relationship and contrasts with the lack of differentiation observed among host-lineages in N. ceranae (< 4% of the variance), which suggests that the spread of this emergent pathogen throughout the A. mellifera worldwide population is a recent event.This study was supported by funds from the Instituto Nacional de Investigación y Tecnología Agraria (INIA; http://www.inia.es/; grant numbers RTA2013-00042-C10-05 and 06), the Regional Government of Murcia (Fundación Séneca; http://fseneca.es/; grant number 19908/GERM/2015) and the Ministerio de Agricultura, Alimentación y Medio Ambiente (MAGRAMA; Plan Apícola Nacional 2014; http://www.magrama.gob.es). PDR is presently a member and receives support from COST Action FA1307, Sustainable pollination in Europe: joint research on bees and other pollinators, SUPER-B (http://www.cost.eu/COST_Actions/fa/Actions/FA1307)S
Playing with the weakest supramolecular interactions in a 3D crystalline hexakis[60]fullerene induces control over hydrogenation selectivity
Weak forces can play an essential role in chemical reactions. Controlling such subtle forces inreorganization processes by applying thermal or chemical stimuli represents a novel synthetic strategyand one of the main targets in supramolecular chemistry. Actually, to separate the differentsupramolecular contributions to the stability of the 3D assemblies is still a major challenge. Therefore,a clear differentiation of these contributions would help in understanding the intrinsic nature as well asthe chemical reactivity of supramolecular ensembles. In the present work, a controlled reorganization ofan hexakis[60]fullerene-based molecular compound purely governed by the weakest van der Waalsinteractions known,i.e.the dihydrogen interaction-usually called stickyfingers-is illustrated. This pre-reorganization of the hexakis[60]fullerene under mild conditions allows a further selective hydrogenationof the crystalline materialviahydrazine vapors exposure. This unique two-step transformation process ismonitored by single-crystal to single-crystal diffraction (SCSC) which allows the direct observation of themolecular movements in the lattice and the subsequent solid-gas hydrogenation reaction
A survey of modulation of gut microbiota by dietary polyphenols
Dietary polyphenols present in a broad range of plant foods have been related to beneficial health effects. This review aims to update the current information about the modulation of the gut microbiota by dietary phenolic compounds, from a perspective based on the experimental approaches used. After referring to general aspects of gut microbiota and dietary polyphenols, studies related to this topic are presented according to their experimental design: batch culture fermentations, gastrointestinal simulators, animal model studies, and human intervention studies. In general, studies evidence that dietary polyphenols may contribute to the maintenance of intestinal health by preserving the gut microbial balance through the stimulation of the growth of beneficial bacteria (i.e., lactobacilli and bifidobacteria) and the inhibition of pathogenic bacteria, exerting prebiotic-like effects. Combination of in vitro and in vivo models could help to understand the underlying mechanisms in the polyphenols-microbiota-host triangle and elucidate the implications of polyphenols on human health. From a technological point of view, supplementation with richpolyphenolic stuffs (phenolic extracts, phenolic-enriched fractions, etc.) could be an effective option to improve health benefits of functional foods such as the case of dairy fermented foods.The authors of this review were funded by the Spanish MINECO through different projects (AGL2012-40172-C02-01, AGL2010-17499, and BFU2012-35228) and the CONSOLIDER INGENIO 2010 programme (project FUN-CFOOD, CSD2007-063), as well as Comunidad de Madrid (project ALIBIRD P2009/AGR-1469). Montserrat Duenas would like to thank the Spanish “Ramon y Cajal” Programme for a contract.Peer Reviewe
- …