129 research outputs found
Precarious Writings. Reckoning the Absences and Reclaiming the Legacies in the Current Poetics/Politics of Precarity
Scholarly debates over precarity are gaining unprecedented visibility across fields. From labor insecurity forming a growing dangerous class to the existential condition of vulnerability induced by millennial capitalism, precarity has become an object of both empirical study and theoretical reflection. While European social movements have been organizing and writing about precarity from the late 1970s to today, still, from the US perspective, the term precarity might be mistakenly taken as strictly a scholarly invention. “Precarious Writings” offers an important corrective to the ways that precarity has been taken up in anthropology and cognate disciplines, addressing the specific epistemological and political limitations of existing usages and returning the concept to its overlooked grassroots history in social movement struggles in southern Europe. By returning precarity to these activist roots, this paper makes the case for the recognition of social movements as knowledge producers as well as sources of theoretical insight and innovation in their own right. By failing to recognize precarity’s development within contentious struggles, scholarly uses miss how the activist notion enables identity reformulations toward a kind of “precarity pride.” That is, the politicization of insecurity has become a source for nurturing a fluid space of political creation
La migración como (f)actor geopolítico: una aproximación desde la autonomía de la migración
In this article we suggest to interpret migration as a geopolitical factor, a factor which is not always subject to governmental decisions. We conduct a review of the literature on the geopolitics of migration, focusing on migration control, identifying its limits and possibilities. We then present the Autonomy of Migration approach as a way to complement or challenge certain assumptions of the geopolitics of migration literature, such as the analytical primacy of state actions in the migratory field. Using the work of Yann Moulier Boutang, we propose paying attention to the capacity of migratory movement to intervene in the transformation of economic, political, cultural and legal structures. This focus on migrations as a geopolitical factor can guide future research and enrich our understanding of how borders are transforming and of geopolitics itself. En este artículo sugerimos interpretar la migración como factor geopolítico, un factor que no esta siempre sujeto a las decisiones estatales. Realizamos una revisión de la literatura sobre la geopolítica de las migraciones, sobre todo centrado en el control migratorio, identificando sus limites y potencialidades. Después, presentamos la Autonomía de las Migraciones como una manera de complementar o retar conceptos asumidos dentro la literatura de la geopolítica de las migraciones como la primacía analítica de las actuaciones de los estados en materia migratoria. En base al trabajo de Yann Moulier Boutang, proponemos prestar atención a la capacidad propia de los movimientos migratorios para intervenir en transformaciones estructurales de tipo económico, político, cultural y legal. Este enfoque en las migraciones como factor geopolítico puede guiar futuras investigaciones y enriquecer nuestra comprensión de las transformaciones en las fronteras y de la geopolítica misma
New rhenium complexes with ciprofloxacin as useful models for understanding the properties of [99mTc]-ciprofloxacin radiopharmaceutical
Rhenium complexes with the antibiotic ciprofloxacin have been prepared to be studied as models of technetium radiopharmaceuticals. With this aim, the new rhenium complexes 1 {[ReO(Cpf)2]Cl}, 2 {[ReO(CpfH)2]Cl3} and 3 {fac-[Re(CO)3(H2O)(Cpf)]} with ciprofloxacin (CpfH=ciprofloxacin; Cpf=conjugated base of ciprofloxacin) have been synthesised and characterised by elemental analyses, IR, NMR ((1)H, (19)F and (13)C CP-MAS) spectroscopy, as well as MS measurements. All spectroscopic data are consistent with the coordination of ciprofloxacin in all these complexes through the carbonyl and the carboxylate oxygen atoms with the formation of a six member chelate ring. The study of a Tc-ciprofloxacin solution by ESI-MS reveals the presence of [TcO(Cpf)2](+) cations, which agrees with the hypothesis that complexes 1 and 2 can be seen as model rhenium complexes of this radiopharmaceutical. Antimicrobial and DNA gyrase inhibition studies performed with complexes 2 and 3 have shown a very similar behaviour between complex 2 and the free antibiotic, whereas complex 3 exhibit a lower antimicrobial activity. Based on a joint analysis of the data reported in the literature and the chemical and biological results obtained in this study, a tentative proposal to explain some aspects of the behaviour of Tc-ciprofloxacin radiopharmaceutical has been made
Exploration into the origins and mobilization of di-hydrofolate reductase genes and the emergence of clinical resistance to trimethoprim
Trimethoprim is a synthetic antibacterial agent that targets folate biosynthesis by competitively binding to the di-hydrofolate reductase enzyme (DHFR). Trimethoprim is often administered synergistically with sulfonamide, another chemotherapeutic agent targeting the di-hydropteroate synthase (DHPS) enzyme in the same pathway. Clinical resistance to both drugs is widespread and mediated by enzyme variants capable of performing their biological function without binding to these drugs. These mutant enzymes were assumed to have arisen after the discovery of these synthetic drugs, but recent work has shown that genes conferring resistance to sulfonamide were present in the bacterial pangenome millions of years ago. Here, we apply phylogenetics and comparative genomics methods to study the largest family of mobile trimethoprim-resistance genes (dfrA). We show that most of the dfrA genes identified to date map to two large clades that likely arose from independent mobilization events. In contrast to sulfonamide resistance (sul) genes, we find evidence of recurrent mobilization in dfrA genes. Phylogenetic evidence allows us to identify novel dfrA genes in the emerging pathogen , and we confirm their resistance phenotype in vitro. We also identify a cluster of dfrA homologues in cryptic plasmid and phage genomes, but we show that these enzymes do not confer resistance to trimethoprim. Our methods also allow us to pinpoint the chromosomal origin of previously reported dfrA genes, and we show that many of these ancient chromosomal genes also confer resistance to trimethoprim. Our work reveals that trimethoprim resistance predated the clinical use of this chemotherapeutic agent, but that novel mutations have likely also arisen and become mobilized following its widespread use within and outside the clinic. Hence, this work confirms that resistance to novel drugs may already be present in the bacterial pangenome, and stresses the importance of rapid mobilization as a fundamental element in the emergence and global spread of resistance determinants
Genomics of three new bacteriophages useful in the biocontrol of Salmonella
Non-typhoid Salmonella is the principal pathogen related to food-borne diseases throughout the world. Widespread antibiotic resistance has adversely affected human health and has encouraged the search for alternative antimicrobial agents. The advances in bacteriophage therapy highlight their use in controlling a broad spectrum of food-borne pathogens. One requirement for the use of bacteriophages as antibacterials is the characterization of their genomes. In this work, complete genome sequencing and molecular analyses were carried out for three new virulent Salmonella-specific bacteriophages (UAB_Phi20, UAB_Phi78, and UAB_Phi87) able to infect a broad range of Salmonella strains. Sequence analysis of the genomes of UAB_Phi20, UAB_Phi78, and UAB_Phi87 bacteriophages did not evidence the presence of known virulence-associated and antibiotic resistance genes, and potential immunoreactive food allergens. The UAB_Phi20 genome comprised 41,809 base pairs with 80 open reading frames (ORFs); 24 of them with assigned function. Genome sequence showed a high homology of UAB_Phi20 with Salmonella bacteriophage P22 and other P22likeviruses genus of the Podoviridae family, including ST64T and ST104. The DNA of UAB_Phi78 contained 44,110 bp including direct terminal repeats (DTR) of 179 bp and 58 putative ORFs were predicted and 20 were assigned function. This bacteriophage was assigned to the SP6likeviruses genus of the Podoviridae family based on its high similarity not only with SP6 but also with the K1-5, K1E, and K1F bacteriophages, all of which infect Escherichia coli. The UAB_Phi87 genome sequence consisted of 87,669 bp with terminal direct repeats of 608 bp; although 148 ORFs were identified, putative functions could be assigned to only 29 of them. Sequence comparisons revealed the mosaic structure of UAB_Phi87 and its high similarity with bacteriophages Felix O1 and wV8 of E. coli with respect to genetic content and functional organization. Phylogenetic analysis of large terminase subunits confirms their packaging strategies and grouping to the different phage genus type. All these studies are necessary for the development and the use of an efficient cocktail with commercial applications in bacteriophage therapy against Salmonella
How can we improve energy efficiency through user-directed vectorization and task-based parallelization?
Heterogeneity, parallelization and vectorization are key techniques to improve the performance and energy efficiency of modern computing systems. However, programming and maintaining code for these architectures poses a huge challenge due to the ever-increasing architecture complexity. Task-based environments hide most of this complexity, improving scalability and usage of the available resources. In these environments, while there has been a lot of effort to ease parallelization and improve the usage of heterogeneous resources, vectorization has been considered a secondary objective. Furthermore, there has been a swift and unstoppable burst of vector architectures at all market segments, from embedded to HPC. Vectorization can no longer be ignored, but manual vectorization is tedious, error-prone, and not practical for the average programmer. This work evaluates the feasibility of user-directed vectorization in task-based applications. Our evaluation is based on the OmpSs programming model, extended to support user-directed vectorization for different SIMD architectures (i.e. SSE, AVX2, AVX512, etc). Results show that user-directed codes achieve manually-optimized code performance and energy efficiency with minimal code modifications, favoring portability across different SIMD architectures
Crecimiento de Baccharis macrantha y Viburnum triphyllum, dos especies nativas útiles en restauración ecológica, plantadas en un pastizal andino (Boyacá, Colombia)
We evaluated the effect of the application of nutrients on the growth of Baccharis macrantha and Viburnum triphyllum, which were planted in a pasture located on the edge of an oak forest in Arcabuco (Boyacá, Colombia). The following treatments were established in plots: B. macrantha with nutrients, B. macrantha without nutrients, V. triphyllum with nutrients, and V. triphyllum without nutrients, each one with three repetitions. The phytosanitary condition, greatest and least diameter of the plant canopy, and height were measured for each planted individual. Analysis of planted species survival using the Kaplan-Meier method was performed and rates of relative growth (RGR) of height and coverage were calculated for all individuals, with which ANOVAs were performed to assess differences between treatments. The probability of survival of planted species decreased greatly over time. Significant differences between treatments were found for height and cover. According to field observation and statistical analysis, the application of nutrients considerably improved the growth in height and cover of B. macrantha, a result useful for the implementation of ecological restoration activities in pastures.Se evaluó el efecto de la aplicación de nutrientes sobre el crecimiento de Baccharis macrantha y Viburnum triphyllum, plantadas en un pastizal ubicado en el borde de un bosque de roble en Arcabuco (Boyacá, Colombia). Los tratamientos establecidos en parcelas fueron: B. macrantha con nutrientes, B. macrantha sin nutrientes, V. triphyllum con nutrientes y V. triphyllum sin nutrientes, cada uno con tres repeticiones. Se registró el estado fitosanitario, diámetro mayor y menor de la copa y altura de todos los individuos plantados. Se realizó el análisis de supervivencia de las especies plantadas por el método de Kaplan-Meier y se calcularon las tasas de crecimiento relativo (TCR) de altura y cobertura para todos los individuos, con las cuales se realizaron ANOVAS para evaluar diferencias entre tratamientos. La probabilidad de supervivencia de las especies plantadas disminuyó en gran medida a través del tiempo. Se encontraron diferencias significativas para el factor especie en la variable altura y diferencias significativas para la interacción especie-nutriente
para la cobertura. De acuerdo a los análisis estadísticos y observación en campo la aplicación de nutrientes benefició considerablemente el crecimiento en altura y cobertura de la especie B. macrantha, resultado útil para la implementación de actividades de restauración ecológica en pastizales
Repurposing Disulfiram as an Antimicrobial Agent in Topical Infections
Antimicrobial drugs applied topically offer several advantages. However, the widespread use of antibiotics has led to increasing antimicrobial resistance. One interesting approach in the drug discovery process is drug repurposing. Disulfiram, which was originally approved as an anti-alcoholism drug, offers an attractive alternative to treat topical multidrug resistance bacteria in skin human infections. This study aimed to evaluate the biopharmaceutical characteristics of the drug and the effects arising from its topical application in detail. Microdilution susceptibility testing showed antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Streptococcus pyogenes. Dermal absorption revealed no permeation in pig skin. The quantification of the drug retained in pig skin demonstrated concentrations in the stratum corneum and epidermis, enough to treat skin infections. Moreover, in vitro cytotoxicity and micro-array analyses were performed to better understand the mechanism of action and revealed the importance of the drug as a metal ion chelator. Together, our findings suggest that disulfiram has the potential to be repurposed as an effective antibiotic to treat superficial human skin infections
Genetic diversity and population structure of Ascochyta rabiei from the western Iranian Ilam and Kermanshah provinces using MAT and SSR markers
Knowledge of genetic diversity in A. rabiei provides different levels of information that are important in the management of crop germplasm resources. Gene flow on a regional level indicates a significant potential risk for the regional spread of novel alleles that might contribute to fungicide resistance or the breakdown of resistance genes. Simple sequence repeat (SSR) and mating type (MAT) markers were used to determine the genetic structure, and estimate genetic diversity and the prevalence of mating types in 103 Ascochyta rabiei isolates from seven counties in the Ilam and Kermanshah provinces of western Iran (Ilam, Aseman abad, Holaylan, Chardavol, Dareh shahr, Gilangharb, and Sarpul). A set of 3 microsatellite primer pairs revealed a total of 75 alleles; the number of alleles varied from 15 to 34 for each marker. A high level of genetic variability was observed among A. rabiei isolates in the region. Genetic diversity was high (He = 0.788) within populations with corresponding high average gene flow and low genetic distances between populations. The smallest genetic distance was observed between isolates from Ilam and Chardavol. Both mating types were present in all populations, with the majority of the isolates belonging to Mat1-1 (64%), but within populations the proportions of each mating type were not significantly different from 50%. Results from this study will be useful in breeding for Ascochyta blight-resistant cultivars and developing necessary control measures
Antibacterial films based on MOF composites that release iodine passively or upon triggering by near-infrared light
This work was supported by the CERCA Program/Generalitat de Catalunya.Multidrug-resistant bacteria have become a global health problem for which new prophylactic strategies are now needed, including surface-coatings for hospital spaces and medical equipment. This work reports the preparation and functional validation of a metal-organic framework (MOF) based composite for the triggered controlled release of iodine, an antimicrobial element that does not generate resistance. It comprises beads of the iodophilic MOF UiO-66 containing encapsulated gold nanorods (AuNRs) coated with a silica shell. Irradiation of the AuNRs with near-infrared light (NIR) provokes a photothermal effect and the resultant heat actively liberates the iodine. After validating the performance of this composite, it is integrated into a polymer for the development of antibacterial films. This work assesses the adsorption of iodine into these composite films, as well as its passive long-term release and active light-triggered. Finally, this work validates the antibacterial activity of the composite films in vitro against gram-positive and gram-negative bacteria. The findings will surely inform the development of new prophylactic treatments
- …