45 research outputs found
The Role of Subclass Switching in the Pathogenesis of Endemic Pemphigus Foliaceus
Endemic pemphigus foliaceus, like the sporadic form seen in the developed world, is mediated by IgG antibodies to desmoglein-1. We studied an endemic focus in Limao Verde, Brazil, where disease prevalence is 3.4%. We previously detected IgG antibodies to desmoglein-1 in 97% of patients, but also in 55% of normal subjects in the endemic focus, with progressively lower levels in normal subjects in surrounding areas. An environmental trigger is hypothesized to explain these and other findings. In this study we sought to determine if patients and enzyme-linked-immunosorbent-assay-positive normal subjects in Limao Verde differ in IgG subclass response to desmoglein-1. We developed a sensitive and specific subclass enzyme-linked immunosorbent assay using recombinant desmoglein-1 and standardized the assay to enable comparability between the four subclasses. We found that normal subjects have an IgG1 and IgG4 response, whereas patients have similar levels of IgG1 but a mean 19.3-fold higher IgG4 response. Patients in remission have a weak IgG4 response, and a 74.3-fold higher IgG4 response is associated with active disease. Finally, in five patients in whom we had blood samples from both before and after the onset of clinical disease, a mean 103.08-fold rise in IgG4 was associated with onset of clinical disease, but only a mean 3.45-fold rise in IgG1. These results suggest that the early antibody response in normal subjects living in the endemic area and in patients before the onset of clinical disease is mainly IgG1. Acquisition of an IgG4 response is a key step in the development of clinical disease
Low birthweight, preschool education, and school remediation
Abstract
Studies have documented a strong relationship between low birth weight status and adverse child
outcomes such as poor school performance and need for special education services. Following a cohort of
over 1,300 low-income and predominately African American children in the Chicago Longitudinal Study
we investigated whether birth weight and family socio-economic risk measured at the time of the child’s
birth predicts placement into special education classes or grade retention in elementary school. Contrary
to previous research, we found that low birth weight (< 5 ½ pounds) does not predict special education
placement. Rather, these children (especially boys) were more likely to be retained in grade as an
alternative approach to addressing poor school performance. Family socio-economic risk at birth was a
significant predictor of the need for remedial services. We also assessed whether a high-quality preschool
program offered at ages 3 and 4 can reduce the negative effects of low family SES and birth weight on the
need for special education and grade retention. Preschool participation in the Child-Parent Centers was
found to reduce the likelihood of school remediation. The effects of preschool were greater for children
from families with higher levels of socio-economic disadvantage. The beneficial effects of preschool on
special education placement were also larger for boys than girls
On the sensitivity of the HAWC observatory to gamma-ray bursts
We present the sensitivity of HAWC to Gamma Ray Bursts (GRBs). HAWC is a very
high-energy gamma-ray observatory currently under construction in Mexico at an
altitude of 4100 m. It will observe atmospheric air showers via the water
Cherenkov method. HAWC will consist of 300 large water tanks instrumented with
4 photomultipliers each. HAWC has two data acquisition (DAQ) systems. The main
DAQ system reads out coincident signals in the tanks and reconstructs the
direction and energy of individual atmospheric showers. The scaler DAQ counts
the hits in each photomultiplier tube (PMT) in the detector and searches for a
statistical excess over the noise of all PMTs. We show that HAWC has a
realistic opportunity to observe the high-energy power law components of GRBs
that extend at least up to 30 GeV, as it has been observed by Fermi LAT. The
two DAQ systems have an energy threshold that is low enough to observe events
similar to GRB 090510 and GRB 090902b with the characteristics observed by
Fermi LAT. HAWC will provide information about the high-energy spectra of GRBs
which in turn could help to understanding about e-pair attenuation in GRB jets,
extragalactic background light absorption, as well as establishing the highest
energy to which GRBs accelerate particles
Team dynamics in emergency surgery teams: results from a first international survey
Background: Emergency surgery represents a unique context. Trauma teams are often multidisciplinary and need to operate under extreme stress and time constraints, sometimes with no awareness of the trauma\u2019s causes or the patient\u2019s personal and clinical information. In this perspective, the dynamics of how trauma teams function is fundamental to ensuring the best performance and outcomes. Methods: An online survey was conducted among the World Society of Emergency Surgery members in early 2021. 402 fully filled questionnaires on the topics of knowledge translation dynamics and tools, non-technical skills, and difficulties in teamwork were collected. Data were analyzed using the software R, and reported following the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). Results: Findings highlight how several surgeons are still unsure about the meaning and potential of knowledge translation and its mechanisms. Tools like training, clinical guidelines, and non-technical skills are recognized and used in clinical practice. Others, like patients\u2019 and stakeholders\u2019 engagement, are hardly implemented, despite their increasing importance in the modern healthcare scenario. Several difficulties in working as a team are described, including the lack of time, communication, training, trust, and ego. Discussion: Scientific societies should take the lead in offering training and support about the abovementioned topics. Dedicated educational initiatives, practical cases and experiences, workshops and symposia may allow mitigating the difficulties highlighted by the survey\u2019s participants, boosting the performance of emergency teams. Additional investigation of the survey results and its characteristics may lead to more further specific suggestions and potential solutions
The energy spectrum of cosmic rays beyond the turn-down around 10^17 eV as measured with the surface detector of the Pierre Auger Observatory
We present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of the spectrum is observed, confirming the presence of the so-called second-knee feature. The spectrum is then combined with that of the 1500 m array to produce a single measurement of the flux, linking this spectral feature with the three additional breaks at the highest energies. The combined spectrum, with an energy scale set calorimetrically via fluorescence telescopes and using a single detector type, results in the most statistically and systematically precise measurement of spectral breaks yet obtained. These measurements are critical for furthering our understanding of the highest energy cosmic rays
Freshwater mussels from South America: state of the art of Unionida, specially Rhipidodontini
International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009
The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved
Factores de ajuste para la pérdida de carga por fricción en tuberías con salidas múltiples telescópicas o con servicio mixto
[ES] En este artículo se presentan dos expresiones para valorar el factor de ajuste en el cálculo de la pérdida de carga por fricción en tuberías con salidas múltiples telescópicas (constituidas por dos o más tramos de tubería con diámetro de diferente magnitud o tipo de material) o con servicio mixto (tramo de tubería en el que el diámetro y el tipo de material se mantienen invariables, que conduce y distribuye caudal). La característica fundamental de estos factores es su simplicidad, ya que exhiben una representación similar a la del conocido factor de ajuste para el cálculo de pérdida de carga por fricción en tuberías con salidas múltiples de Christiansen. Los resultados obtenidos al computar el factor de ajuste con las experiencias propuestas en las aplicaciones desarrolladas, muestran que son tan precisas como las de otros investigadores, precisión que se puede verificar fácilmente con la determinación de la pérdida de carga en una tubería con salidas múltiples, segmento a segmento entre salidas consecutivas. Se concluye así, que las ecuaciones que se proponen para valorar el factor de ajuste en el cálculo de la pérdida de carga por fricción en el tipo de tuberías referido, evita la determinación tediosa segmento a segmento entre salidas consecutivas de dicha pérdida, en toda la gama de situaciones que en la práctica se pueden prestar en la ejecución de proyectos de riego a presión. Finalmente, pero no por ello menos importante, es el hecho de que se prevé un grado de aceptación considerable de las ecuaciones de estos factores de ajuste por los especialistas en el ramo de la irrigación dada su simplicidad, precisión y representación conocida.Ángeles, V.; Arteaga, R.; Vázquez Peña, M.; Carrillo García, M.; Ibáñez Castillo, L. (2007). Factores de ajuste para la pérdida de carga por fricción en tuberías con salidas múltiples telescópicas o con servicio mixto. Ingeniería del agua. 14(4):293-305. https://doi.org/10.4995/ia.2007.2918OJS293305144Anwar A., (1999a). Factor G for pipelines with equally spaced multiple outlets and outflow. Journal of Irrigation and Drainage Engineering, 125(1), 34-38.Anwar A., (1999b). Adjusted Factor Ga for pipelines with multiple outlets and outflow. Journal of Irrigation and Drainage Engineering, 125(6), 355-339.Chinea R. y Domínguez A., (2006). Total Friction Loss along Multiple Outlets Pipes with Open End. Journal of Irrigation and Drainage Engineering, 132(1), 31-40.Christiansen J.E., (1942). Irrigation by Sprinkling. California Agric. Experiment Station Bull. No. 670, University of California, Davis, Calif.Churchill S.W., (1977). Friction-factor equation spans all fluid-flow regimes. Chem. Engrg., 84(24), 91-92.Jensen M.C. y Fratini A.M., (1957). Adjusted "F" factors for sprinkler lateral design. Agric. Engrg., 38(4), 247.Scaloppi E.J., (1988). Ajusted "F" factor for multiple-outlet pipes. Journal of Irrigation and Drainage Engineering, ASCE, 114(1), 169-174
Relleno de series diarias de precipitación, temperatura mínima, máxima de la región norte del Urabá Antioqueño
Agroclimatic studies require the use of time series of meteorological variables, which generally present missing data limiting its use, so filling methods are used.
The purpose of this study was to determine the reliability of filling methods: US National Weather Servicie (WS), rational deductive (RD), multiple regression (MR) and linear regression (LR) and from them use the best to fill the data series of precipitation, maximum
and minimum temperature during the period 2006-2009 of the stations located in the northern area on banana axis from Urabá Antoquia. The base station was Pïsta Indira, and Uniban, Turbo, Aeropuerto and Prado Mar stations were used as neighbors. Standard
error was made with: square root of the mean squared error (RCCME), coefficient of determination (R2), mean absolute error (MAE), relative error (RE) and Willmott’s concordance index (d). RM and RL methods presented similar RCCME and MAE to those of WS, which would lead to have similar errors but due to R2 of the first were 0.8 and the index (d) for WS was higher or similar to the other method, the latter was used to fill in the series.Los estudios agroclimáticos requieren la utilización de series cronológicas de las variables meteorológicas, que generalmente presentan datos faltantes limitando su uso, por lo que los métodos de relleno son utilizados. La finalidad de este trabajo fue determinar la confiablidad de los métodos de relleno: U.S National Weather Servicie (WS), deductivo racional (RD), la regresión múltiple (RM) y regresión lineal (RL) y de ellos utilizar el mejor para rellenar los datos de las series de precipitación, temperatura máxima y temperatura mínima en el periodo 2006-2009 de las estaciones ubicadas en la zona Norte del eje bananero del Urabá Antioqueño. La estación base fue la estación Pista Indira, y las estaciones Uniban, Turbo, Aeropuerto y Prado Mar se utilizaron como vecinas. La estimación del error se hizo con la: raíz cuadrada del cuadrado medio del error (RCCME), coeficiente de determinación (R2), error medio absoluto (MAE), error relativo (RE) e Índice de concordancia de Willmott (d). Los métodos RM y RL presentaron RCCME y MAE similares a los del WS, lo que con llevaría a tener errores similares pero debido a que la R2 de los primeros fueron menores de 0.8 y el índice (d) para WS fue mayor o similar a lo demás método, se utilizó este último para el relleno de las series