MEDUSA: An open-source and webcam based multispectral imaging system.

Multispectral imaging is at the forefront of contactless surface analysis. Standard multispectral imaging systems use sophisticated software, cameras and light filtering optics. This paper discloses the building of a customizable and cost-effective multispectral imaging and analysis system. It integrates a web camera, light emitting diodes (LEDs) lighting, a semisphere for even lightening, an open-source Arduino™ development board and a free Python application to automatically obtain and visually analyze multispectral images. The device is hereafter called MEDUSA and its optical performance was tested for repeated Imaging consistency, visible and near infrared band sensitivity and lighting evenness. Four proof of concept tests were run in order to understand the advantageous use of this system, as compared to a simple visual score of diverse samples. Each of three qualitative tests used sets of 12 LED band spectral images to analyze ink changes in a counterfeit bill, surface bruises on Hass avocado fruits and transient changes in petri dish grown bacterial colonies. A fourth test used single band imaging in a set of standard laboratory analyzed plant samples, to quantitatively relate a red band light reflectance to its nitrogen content. These tests indicate that MEDUSA made images may yield qualitative and quantitative spectral information unseen to the naked eye, suggesting potential use in currency counterfeit tests, food quality analyses, microbial phenotyping and agricultural plant chemistry. MEDUSA can be freely reproduced and customized from this research, making it a powerful and affordable analytical tool to analyze a wide range of subtle chemical properties in samples at industrial and science fields.

A prospective randomized controlled trial of an interpersonal violence prevention program with a Mexican American community.

Using methods of community-based participatory research, a prospective randomized controlled trial of a violence prevention program based on Latino cultural values was implemented with elementary school children in a Mexican American community. Community members participated in intervention program selection, implementation, and data collection. High-risk students who participated in the program had greater nonviolent self-efficacy and demonstrated greater endorsement of program values than did high-risk students in the control group. This collaborative partnership was able to combine community-based participatory research with a rigorous study design and provide sustained benefit to community partners.

[Snake bites accidents in Yopal and Leticia, Colombia, 1996-1997]. / Accidentes ofídicos en Yopal y Leticia, Colombia, 1996-1997.

Snakebites produce notable morbidity and mortality in the Amazonian and Orinocan regions of Colombia. A review was undertaken of 56 snakebite cases sent to hospitals in Leticia (Amazonas) and Yopal (Casanare) between September 1996 and June 1997. Of the total, 57% of the bites occurred in Leticia, 54% in men. The 14 to 44 year-old age group was most compromised (41%). Most encounters occurred in forests and open fields between 17:00 and 18:00 hours (57%). Nearly all bites were located on legs and feet (82%). One death occurred in Yopal; 3 fasciotomies and 2 amputations were performed. Snakebite incidence occurred with highest probability during evening hours. Although antibiotics are in general use, minor infections (16%) were frequent.

Síndrome hemorrágico por contacto conorugas del género Lonomia (Saturniidae en Casanare, Colombia: informe de dos casos / Hemorrhagic syndrome caused by Lonomia (Saturniidae) caterpillars in Casanare, Colombia

El presente artículo describe los dos primeros casos de accidentes por orugas de Lonomia diagnósticados en Colombia. Estos insectos ocasionan un cuadro local con alteraciones hemorrágicas caracterizadas por una intensa actividad fibrinolítica y valores bajos de diferentes factores de la coagulación. Los dos casos se presentaron en el departamento de Casanare y fueron remitidos al Hospital San Carlos de Bogotá. La evolución de cada uno fue diferente: el primero, con hemoptisis e insuficiencia renal secundaria, que le causó la muerte a la paciente; el segundo, con gingivorragia y sangrado vaginal que evolucionó hasta la completa mejoría después de la adminitración del sueo anti-Lonomia. Descritos estos primeros casos, es necesario ampliar el conocimiento sobre el tema y trabajar en su prevención