420 research outputs found

    Testing Universality in Critical Exponents: the Case of Rainfall

    Full text link
    One of the key clues to consider rainfall as a self-organized critical phenomenon is the existence of power-law distributions for rain-event sizes. We have studied the problem of universality in the exponents of these distributions by means of a suitable statistic whose distribution is inferred by several variations of a permutational test. In contrast to more common approaches, our procedure does not suffer from the difficulties of multiple testing and does not require the precise knowledge of the uncertainties associated to the power-law exponents. When applied to seven sites monitored by the Atmospheric Radiation Measurement Program the test lead to the rejection of the universality hypothesis, despite the fact that the exponents are rather close to each other

    Probability estimation of a Carrington-like geomagnetic storm

    Get PDF
    Intense geomagnetic storms can cause severe damage to electrical systems and communications. This work proposes a counting process with Weibull inter-occurrence times in order to estimate the probability of extreme geomagnetic events. It is found that the scale parameter of the inter-occurrence time distribution grows exponentially with the absolute value of the intensity threshold defining the storm, whereas the shape parameter keeps rather constant. The model is able to forecast the probability of occurrence of an event for a given intensity threshold; in particular, the probability of occurrence on the next decade of an extreme event of a magnitude comparable or larger than the well-known Carrington event of 1859 is explored, and estimated to be between 0.46% and 1.88% (with a 95% confidence), a much lower value than those reported in the existing literature

    Apoptosis, mastocytosis, and diminished adipocytokine gene expression accompany reduced epididymal fat mass in long-standing diet-induced obese mice

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Obesity is characterized by increased cell death and inflammatory reactions in the adipose tissue. Here, we explored pathophysiological alterations taking place in the adipose tissue in long-standing obesity. In the epididymal fat of C57BL/6 mice fed a high-fat diet for 20 weeks, the prevalence and distribution of dead adipocytes (crown-like structures), mast cells (toluidine blue, mMCP6), macrophages (F4/80), and apoptotic cells (cleaved caspase-3) were measured. Moreover, gene and/or protein expression of several adipocytokines (leptin, adiponectin, TNF-α, IL-10, IL-6, MCP-1), F4/80, mMCP6, cleaved caspase-3 were determined.</p> <p>Results</p> <p>We observed that the epididymal fat mass was lower in obese than in lean mice. In obese mice, the epididymal fat mass correlated inversely with body weight and liver mass. Dead adipocytes, mast cells, macrophages, and apoptotic cells were abundant in the epididymal fat of obese mice, especially in the rostral vs. caudal zone. Accordingly, mMCP6, F4/80, and cleaved caspase-3 gene and/or protein expression was increased. Conversely, adiponectin, leptin, IL-6, and MCP-1 gene expression levels were lower in the epididymal fat of obese than lean mice. Although TNF-α and IL-10 gene expression was higher in the epididymal fat of obese mice, their expression relative to F4/80 and mMCP6 expression were lower in the heavily infiltrated rostral than caudal zone.</p> <p>Conclusions</p> <p>This study demonstrates that in mice with long-standing obesity diminished gene expression of several adipocytokines accompany apoptosis and reduced mass of the epididymal fat. Our findings suggest that this is due to both increased prevalence of dead adipocytes and altered immune cell activity. Differential distribution of metabolically challenged adipocytes is indicative of the presence of biologically diverse zones within the epididymal fat.</p

    Systemic insecticide treatment of the canine reservoir of Trypanosoma cruzi induces high levels of lethality in Triatoma infestans, a principal vector of Chagas disease

    Get PDF
    BACKGROUND: Despite large-scale reductions in Chagas disease prevalence across Central and South America, Trypanosoma cruzi infection remains a considerable public health problem in the Gran Chaco region where vector-borne transmission persists. In these communities, peridomestic animals are major blood-meal sources for triatomines, and household presence of infected dogs increases T. cruzi transmission risk for humans. To address the pressing need for field-friendly, complementary methods to reduce triatomine infestation and interrupt T. cruzi transmission, this study evaluated the systemic activity of three commercial, oral, single dose insecticides Fluralaner (Bravecto(R)), Afoxolaner (NexGard(R)) and Spinosad (Comfortis(R)) in canine feed-through assays against Triatoma infestans, the principal domestic vector species in the Southern Cone of South America. METHODS: Twelve healthy, outbred dogs were recruited from the Zoonosis Surveillance and Control Program in Santa Cruz, Bolivia, and randomized to three treatment groups, each containing one control and three treated dogs. Following oral drug administration, colony-reared second and third stage T. infestans instars were offered to feed on dogs for 30 min at 2, 7, 21, 34 and 51 days post-treatment. RESULTS: Eighty-five per cent (768/907) of T. infestans successfully blood-fed during bioassays, with significantly higher proportions of bugs becoming fully-engorged when exposed to Bravecto(R) treated dogs (P < 0.001) for reasons unknown. Exposure to Bravecto(R) or NexGard(R) induced 100% triatomine mortality in fully- or semi-engorged bugs within 5 days of feeding for the entire follow-up period. The lethality effect for Comfortis(R) was much lower (50-70%) and declined almost entirely after 51 days. Instead Comfortis(R) treatment resulted in substantial morbidity; of these, 30% fully recovered whereas 53% remained morbid after 120 h, the latter subsequently unable to feed 30 days later. CONCLUSIONS: A single oral dose of Fluralaner or Afoxolaner was safe and well tolerated, producing complete triatomine mortality on treated dogs over 7.3 weeks. While both drugs were highly efficacious, more bugs exposed to Fluralaner took complete blood-meals, and experienced rapid knock-down. Coupled with its longer residual activity, Fluralaner represents an ideal insecticide for development into a complementary, operationally-feasible, community-level method of reducing triatomine infestation and potentially controlling T. cruzi transmission, in the Gran Chaco region

    Tailoring Staircase-like Hysteresis Loops in Electrodeposited Tri-segmented Magnetic Nanowires: a Strategy toward Minimization of Interwire Interactions

    Get PDF
    A new strategy to minimize magnetic interactions between nanowires (NWs) dispersed in a fluid is proposed. Such a strategy consists of preparing trisegmented NWs containing two antiparallel ferromagnetic segments with dissimilar coercivity separated by a nonmagnetic spacer. The trisegmented NWs exhibit a staircase-like hysteresis loop with tunable shape that depends on the relative length of the soft- and hard-magnetic segments and the respective values of saturation magnetization. Such NWs are prepared by electrodepositing CoPt/Cu/Ni in a polycarbonate (PC) membrane. The antiparallel alignment is set by applying suitable magnetic fields while the NWs are still embedded in the PC membrane. Analytic calculations are used to demonstrate that the interaction magnetic energy from fully compensated trisegmented NWs with antiparallel alignment is reduced compared to a single-component NW with the same length or the trisegmented NWs with the two ferromagnetic counterparts parallel to each other. The proposed approach is appealing for the use of magnetic NWs in certain biological or catalytic applications where the aggregation of NWs is detrimental for optimized performance

    Structure-based design of a Cortistatin analogue with immunomodulatory activity in models of inflammatory bowel disease

    Get PDF
    Ulcerative colitis and Crohn’s disease are forms of inflammatory bowel disease whose incidence and prevalence are increasing worldwide. These diseases lead to chronic inflammation of the gastrointestinal tract as a result of an abnormal response of the immune system. Recent studies positioned Cortistatin, which shows low stability in plasma, as a candidate for IBD treatment. Here, using NMR structural information, we design five Cortistatin analogues adopting selected native Cortistatin conformations in solution. One of them, A5, preserves the anti-inflammatory and immunomodulatory activities of Cortistatin in vitro and in mouse models of the disease. Additionally, A5 displays an increased half-life in serum and a unique receptor binding profile, thereby overcoming the limitations of the native Cortistatin as a therapeutic agent. This study provides an efficient approach to the rational design of Cortistatin analogues and opens up new possibilities for the treatment of patients that fail to respond to other therapies.A.Rol was a recipient of a PhD fellowship from the Generalitat de Catalunya (FI) and A.E. and E.P. were recipients of PhD fellowships granted by the Severo Ochoa Program(FPI). T.T. was a postdoctoral fellow co-funded by the Marie Skłodowska-CurieCOFUND actions (IRB Barcelona Interdisciplinary Postdoc Programme). This work wassupported by the following grants: CTQ2014-56361-P and CTQ2017-87840-P (A.Riera)and RTI2018-100700-B-100 (M.D.) from the Spanish Ministry of Economy, Industryand Competitiveness (MINECO); and by AGAUR (SGR-50). We also acknowledge institutional funding from MINECO through the Centers of Excellence Severo OchoaAward given to IRB Barcelona, as well as from the CERCA Program of the Generalitat deCatalunya. M.J.M. is an ICREA Programme Investigator

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

    Get PDF
    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Programa intensivo ERASMUS: TOPCART. Documentación Geométrica del Patrimonio (memoria de actividades 2010-2011)

    Get PDF
    [EN] Data contained in this record come from the following accademic activity (from which it is possible to locate additional records related with the Monastery):● LDGP_inv_002: "Intensive Program ERASMUS: TOPCART. Geometric Documentation of the Heritage (administrative and academic documentation)", http://hdl.handle.net/10810/9906[ES] Los datos de este registro provienen de la una actividad académica que también aparece descrita en el repositorio y desde donde se puede acceder a otros trabajos relacionados con el Monasterio:● LDGP_inv_002: "Programa intensivo ERASMUS: TOPCART. Documentación Geométrica del Patrimonio (documentación administrativa y académica)", http://hdl.handle.net/10810/9906[EN] The main objective this project is looking for is the exchange of practical methodologies, in topics related with the measure and representation of heritage, between teachers and specially students from different countries. For the achievement of this aim we expect the participation of a group of about 30 students and 8 lecturers from Germany, Italy, Greece, Lithuania and Spain.Activities will be focused on the development of concrete projects in documentation of heritage, specifically in the San Prudencio Monastery (La Rioja, Spain). In this site, digital techniques for the acquisition of geometric information from GPS equipment, surveying total stations, laser scanner and photogrammetry systems, will be put into practice.Obtained data will be processed as follows: first of all, they will be documented by adding necessary metadata in order to ensure their use in the future, then, they will be treated to obtain cartographic representations and virtual models which can be distributed on the Internet.As results we expect: metric data of the monument, graphic models for difussion and collaboration partnertships.[ES] El objetivo principal que se persigue en este proyecto es el intercambio de metodológico práctico, en materias afines a la medida y la representación del patrimonio, entre profesores y fundamentalmente alumnos, de diferentes países. Para la consecución de este fin se espera la participación de un grupo de aproximadamente 25 alumnos y 8 profesores de (Alemania, Italia, Grecia, Lituania y España).Las actividades se centrarán en el desarrollo de proyectos concretos de documentación de elementos patrimoniales, en concreto el apartado práctico se desarrollará en el Monasterio de San Prudencio (La Rioja, España). En el se aplicarán técnicas digitales de registro de información geométrica, constituidas por receptores GPS, estaciones totales topográficas, escáneres láser y sistemas fotogramétricos.Los datos obtenidos serán tratados de la siguiente manera: en primer lugar serán documentados, mediante la adición de la metainformación necesaria para garantizar su utilidad a lo largo del tiempo, seguidamente serán procesados con el fin de obtener las representaciones cartográficas y modelos virtuales de representación que puedan ser difundidas por medio de Internet.Como resultados se pretenden: un conjunto de registros métricos del momento de la intervención, modelos gráficos de difusión y finalmente relaciones de colaboración interpersonal e interinstitucional.European Commission, DG Education and Culture (Erasmus 2009-1-ES1-ERAIP-0013, 2010-1-ES1-ERA10-0024); Organismo Autónomo Programas Educativos Europeos (OAPEE); Gobierno de La Rioja (Spain); Universidad de La Rioja; Clavijo City Council; Logroño City Council; Ilustre Colegio de Ingenieros Técnicos en Topografía (Delegación de La Rioja)[ES] Memoria de proyecto (PDF) [es el último fichero de la lista, el enlace directo es https://addi.ehu.es/bitstream/10810/7053/1053/ldgp_mem011-1_Clavijo_SanPrudencio.pdf] + 11 imágenes de la visita preliminar en abril de 2009, en formato JPEG + 19 nubes de puntos en formato txt (comprimido en ZIP junto a un fichero de metadatos y una imagen que sirve de croquis y que también se presenta suelta) + 27 fotografías tomadas desde un helicóptero radicontrolado en 2011 por el grupo H (JPEG) + 18 fotografías métricas del edificio en forma de -L- tomadas desde el Sur + 13 fotografías métricas del edificio en forma de -L- tomadas desde el Este + 95 fotografías métricas del interior del edificio en forma de -L- (JPEG) + 35 fotografías métricas tomadas desde el cerro que se encuentra al sur (JPEG) + 8 fotografías métricas que forman 4 pares estereoscópicos (2 del grupo B y 2 del grupo D) (JPEG) + 183 fotografías métricas que forman 91 tripletas (grupos B, C y D) (JPEG). [NOTA: este registro no está cerrado, se irán incorporando nuevos materiales de forma progresiva][EN] General report (PDF) [it is the last file of the list, the direct link is https://addi.ehu.es/bitstream/10810/7053/1053/ldgp_mem011-1_Clavijo_SanPrudencio.pdf] + 11 pictures taken during the preliminary visit in April 2009 (JPEG format) + 19 point clouds in plain text (compressed in a ZIP file together with a file with metadata and an image PNG as sketch, these image are also presented on their own) + 27 photographs taken from a remote-controlled helicopter for the group H in 2011(JPEG) + 18 metric pictures of the L-shaped building taken from the South (JPEG) + 13 metric pictures of the L-shaped building taken from the East (JPEG) + 95 metric pictures of the inside part of the L-shaped building (JPEG) + 35 metric photographs taken from the hill opposite in the Southern + 8 metric photographs in four stereopairs (2 from group B and 2 from group D) (JPEG) + 183 metric photographs arranged in 91 triplets from groups B, C and D (JPEG). [NOTE: this record is not closed, more data will be uploaded progressively
    corecore