Outdoor and synthetic performance data for PV devices concerning the weather conditions and capacitor values of I-V tracer.

This article presents the outdoor and synthetic performance data concerning the main electrical parameters estimated from the I-V curve for three photovoltaic technologies (HIT, m-Si and CIGS) and the weather conditions (irradiance, ambient and panel temperature). Synthetic data were generated by simulating in OpenModelica software the impact of weather conditions on device performance, considering an irradiance range between 50 and 1300 W/m2. The outdoor data corresponds to the performance of the evaluated PV modules in outdoor tests in Medellin-Colombia for ten months using capacitive I-V tracers. In both cases, different capacitor values were considered to evaluate the effect on the I-V curve behavior of devices.

Evaluación antimicrobiana de extractos obtenidos a partir de tithonia diversifolia (hemsl.) a. gray con uso potencial en la industria lechera

El uso de antibióticos en el tratamiento de la mastitis en la industria lechera ha acarreado una problemática con potencial impacto en la salud pública, como la resistencia antimicrobiana. El objetivo del presente trabajo fue evaluar la acción antimicrobiana del extracto alcohólico de hojas, tallos y flores de Tithonia diversifolia sobre el crecimiento de Staphylococcus aureus y Escherichia coli en cultivo in vitro. Se evaluó el efecto inhibitorio en el crecimiento bacteriano a través de un ensayo de sensibilidad. En ambas bacterias el control positivo presentó un halo de inhibición superior a 30 mm, con diferencia significativa de los extractos de T. diversifolia. Los cuales presentaron para S. aureus un halo de 9,7 y 10,4 mm y para E. coli de 6,5 y 9,4 mm para tallo-hoja y flores respectivamente. El extracto alcohólico de flores de T. diversifolia se perfila como una herramienta potencial para inhibir el crecimiento bacteriano.

Antibiotics used as a treatment for mastitis in the dairy industry have brought a problem with a potential impact on public health, such as antimicrobial resistance. The objective of this study is to evaluate the antimicrobial action of alcoholic extract from Tithonia diversifolia's leaves, stems, and flowers on the growth of Staphylococcus aureus and Escherichia coli in in vitro cultures. The inhibitory effect on bacterial growth was evaluated through a sensitivity test. In both bacteria, the positive control presented an inhibition halo greater than 30 mm, with a significant difference from the extracts of T. diversifolia, which presented, for S. aureus, a halo of 9.7 and 10.4 mm and for E. coli of 6.5 and 9.4 mm for stem-leaf and flowers respectively. The alcoholic extract of T. diversifolia flowers is emerging as a potential tool to inhibit bacterial growth.

Enfermedad carcinoide cardiaca multivalvular / Multivalvular carcinoid heart disease

Hombre de 67 años de edad, enviado a valoración ecocardiográfica por cuadro clínico de 6 meses de evolución con: disnea de esfuerzo, edemas de miembros inferiores y fatiga. Se encuentra doble lesión de la válvula tricúspide con: estenosis e insuficiencia severa, insuficiencia pulmonar severa; y compromiso valvular izquierdo con: insuficiencia mitral y aórtica severas, asociadas a engrosamiento y rigidez valvular. El paciente tenía como antecedente tumor neuroendocrino de íleon, metastásico a pulmón e hígado. En este caso se discuten los hallazgos ecocardiográficos característicos del síndrome carcinoide con compromiso multivalvular como hallazgo inusual de este raro síndrome.

A 67 year-old man is sent to echocardiographic assessment for 6 month history of exertional: dyspnea, edema of the lower extremities, fatigue, double lesions in tricuspid valve with: severe stenosis and severe regurgitation, severe pulmonary valve regurgitation; and left side valvular disease with: severe aortic regurgitation and severe mitral regurgitation, all of them associated with valvular thickening, rigidity, in a patient with history of neuroendocrine tumor, with lung and liver metastases. This case discuss the echocardiographic findings suggestive of carcinoid multivalvular and left side valvular disease as unusual finding in this rare syndrome.

Chiari I malformation associated with syringomyelia and scoliosis.

STUDY DESIGN: A retrospective review of a series of 12 children who underwent suboccipital foraminotomy and duroplasty for Chiari I malformation. OBJECTIVE: To assess the effects of this surgery on associated syringomyelia and scoliosis. SUMMARY OF BACKGROUND DATA: Suboccipital foraminotomy for the treatment of syringomyelia associated with Chiari I malformation was greatly stimulated by Gardner's hydrodynamic theory, and its results proved to be encouraging. However, several authors reported improvement or stabilization of associated scoliosis after this surgery. METHODS: A retrospective review was conducted on 12 patients who underwent suboccipital foraminotomy for Chiari I malformation associated with syringomyelia. Neurologic Impairment, extent of syringomyelia, and severity of associated spinal deformity were assessed preoperatively and at a 4.5-year average follow-up (range, 2.1-12 years). Anomaly of superficial abdominal reflexes was found in all cases, and para or tetraparesis in three cases. Syringomyelia was of variable localization and extent. Scoliosis was present in 7 cases (greater than 40 degrees in 5 cases). RESULTS: Diminution or complete disappearance of syringomyelia was observed in 11 cases, 3 months to 1 year after surgery. Superficial abdominal reflexes anomaly improved in four cases. Minimal neurologic deficit persisted in one case. Scoliosis improved in one case, remained unchanged in one case, and progressed in the five cases with preoperative severe deformity, requiring instrumentation and fusion. CONCLUSIONS: Improvement of syringomyelia and neurologic deficit, observed with suboccipital foraminotomy, supports the theory that abnormal hydrodynamics of the cerebral spinal fluid is most likely to cause these deficits.

Athermalization of a single-component lens with diffractive optics.

We describe a design method to athermalize a single-material lens element by using a kinoform on one surface to keep its focal length and aberrations constant with temperature. We diamond turned and thermally tested a plastic athermat and compared it to an uncompensated conventional lens.

Modeling diffraction efficiency effects when designing hybrid diffractive lens systems.

We investigated the design of two broadband hybrid diffractive-refractive optical systems, a landscape lens, and a Schmidt telescope. The systems were achromatized by using the characteristically large negative dispersion of kinoforms. In the scalar wave regime kinoforms can approach 100% efficiency but only for one object point and wavelength. We evaluated polychromatic image quality, accounting for diffraction efficiency, by constructing weighted geometric point-spread functions from several diffracted orders and then calculating modulation transfer functions (MTF's). The MTF's of the hybrid achromats were improved at high spatial frequencies but were reduced at low frequencies because of diffraction into nondesign orders.

Niveles de presion arterial en ninos normales entre las edades de 4 a 14 anos del Valle de Medellin / Blood pressure levels in normal children from 4 to 14 years old in El Valle de Medellin

El proposito del presente estudio fue observar los valores de presion arterial sistodiastolica en escolares sanos de 4 a 14 anos en el area Metropolitana del Valle de Medellin y su correlacion con las variables antropometricas (peso, talla). Se evaluaron 558 ninos, 280 hombres y 278 mujeres, utilizando esfingomanometros aneroides. Se registro la presion sistolica con la aparicion del primer sonido arterial (Fase I de Korotkoff) y la diastolica con al apagamiento del sonido arterial (Fase IV). Para el procesamiento de datos se utilizo un computador IBM AT. Se obtuvieron la Media, la Desviacion Tipica y los Percentiles 5, 50, 90, 95. Se analizo el coeficiente de determinacion (R2) mediante el cual no hallamos relacion significativa entre la presion arterial y las variables independientes; observamos en cambio, mediante curvas de regresion individuales para cada variable, un aumento de la presion arterial a medida que aumenta la edad