The effects of outdoor access and stocking density on the performance of broilers reared under tropical conditions.

1. The effects of housing system and stocking density on growth performance and carcase yield of a commercial strain of broiler chickens reared under tropical environmental conditions may differ from temperate conditions.2. In two experimental periods, carried out during two contrasting seasons of the year (winter and summer), 240 Cobb 500 male chickens were randomly assigned in groups of 60 to 1 of 4 treatments, with 6 replicates in each, low stocking density with outdoor access (LO, 5 birds/m2); high stocking density with outdoor access (HO, 10 birds/m2); low stocking density indoors (LI, 5 birds/m2); high stocking density indoors (HI, 10 birds/m2). From 21 to 42 d old, body weight (BW) and feed intake (FI) were weekly recorded. Mortality was measured daily and carcase weight at slaughter. Indoor and outdoor temperature and relative humidity were measured daily.3. There was a tendency for chickens raised in the outdoor access to be heavier than those raised in the indoor treatments. Chickens raised in the low-density treatments in the first experimental period were significantly heavier, gained more weight and had lower value for feed conversion ratio (FCR) than those reared at high density. In the second experimental period mortality significantly increased on week 4 due to heat stress. Birds raised with outdoor access had an increased carcase yield compared to those raised exclusively indoors.4. In conclusion, low stocking density in combination with low environmental temperatures had enhancing effects on BW, BWG, FI and FCR, and the effects of housing system depended on stocking density. Low stocking density and outdoor access had positive effects on carcase yield.

Super large cardiac hemangioma in right atrium and inferior vena cava: case report.

BACKGROUND: Cardiac hemangiomas are rare cardiac neoplasia usually diagnosed in autopsies, from being asymptomatic to debuting with sudden death. The largest hemangioma published in the literature is of 130 mm size, we present the following case of a successful cardiac hemangioma excision of 280 × 35 mm in size, diagnosed due to recurrent cardiac symptoms. CASE PRESENTATION: A 48-year-old female patient, Jehovah's Witness, with no previous diagnoses, is admitted due to recurrent syncopal episodes in the previous months. A transthoracic echocardiogram diagnosed a tumor in the right atrium and inferior vena cava producing a diastolic right ventricular, with preservation of the left ventricular ejection fraction at 55%. Given the high mortality risk, a surgical intervention was performed immediately. Successful excision was completed confirming a 280 × 35 mm mass without any complications, consistent with hemangioma on histopathology. Postoperative recovery showed no recurrence or complications. CONCLUSIONS: Cardiac hemangiomas are rare and its clinical course can be varied from patient to patient. We present excision of a large cardiac mass with a high mortality risk due to its size and the patient's spiritual beliefs.

Lichenomphalia altoandina, a new species of Hygrophoraceae from the Chilean Altiplano.

Lichenomphalia is a lichenized agaric genus characterized by its omphalinoid basidiomes. Lichenomphalia species are associated with unicellular green algae in the genus Coccomyxa and are mainly distributed in polar and alpine habitats. The aim of this work is to describe L. altoandina, a new species from northern Chile that grows among cushion plants over 3000 m above sea level in the Andes Mountains. The species is remarkable for living in highly saline environments, in some cases virtually on salt crusts. Lichenomphalia altoandina differs from other known species and particularly from L. aurantiaca, the most morphologically similar species, in its smooth and broader stipe and its slightly larger spores. Lichenomphalia altoandina is also morphologicaly and ecologically more similar to the core Lichenomphalia clade. Our phylogenetic study based on nuclear rDNA ITS and partial 28S sequences shows that L. altoandina belongs to the Protolichenomphalia clade and is sister to an unknown lineage, L. aff. umbellifera, from New Zealand.

Alpha-2 macroglobulin in Alzheimer's disease: a marker of neuronal injury through the RCAN1 pathway.

Preclinical changes that precede the onset of symptoms and eventual diagnosis of Alzheimer's disease (AD) are a target for potential preventive interventions. A large body of evidence suggests that inflammation is closely associated with AD pathogenesis and may be a promising target pathway for such interventions. However, little is known about the association between systemic inflammation and preclinical AD pathophysiology. We first examined whether the acute-phase protein, alpha-2 macroglobulin (A2M), a major component of the innate immune system, was associated with cerebrospinal fluid (CSF) markers of neuronal injury in preclinical AD and risk of incident AD in the predictors of cognitive decline among normal individuals (BIOCARD) cohort. We find that A2M concentration in blood is significantly associated with CSF concentrations of the neuronal injury markers, tau and phosphorylated tau, and that higher baseline serum A2M concentration is associated with an almost threefold greater risk of progression to clinical symptoms of AD in men. These findings were replicated in the Alzheimer's Disease Neuroimaging (ADNI) study. Then, utilizing a systems level approach combining large multi-tissue gene expression datasets with mass spectrometry-based proteomic analyses of brain tissue, we identified an A2M gene network that includes regulator of calcineurin (RCAN1), an inhibitor of calcineurin, a well-characterized tau phosphatase. A2M gene and protein expression in the brain were significantly associated with gene and protein expression levels of calcineurin. Collectively these novel findings suggest that A2M is associated with preclinical AD, reflects early neuronal injury in the disease course and may be responsive to tau phosphorylation in the brain through the RCAN1-calcineurin pathway.

A systematic approach to predicting the risk of unicompartmental knee arthroplasty revision.

OBJECTIVE: Unicompartmental knee arthroplasty (UKA) revision is usually due to the degenerative degree of knee articular osteochondral tissue in the untreated compartment. However, it is difficult to simulate the biomechanical behavior on this tissue accurately. This study presents and validates a reliable system to predict which osteoarthritis (OA) patients may suffer revision as a result of biomechanical reasons after having UKA. DESIGN: We collected all revision cases available (n = 11) and randomly selected 67 UKA cases to keep the revision prevalence of almost 14%. All these 78 cases have been followed at least 2 years. An elastic model is designed to characterize the biomechanical behavior of the articular osteochondral tissue for each patient. After calculated the force on the tissue, finite element method (FEM) is applied to calculating the strain of each tissue node. Kernel Ridge Regression (KRR) method is used to model the relationship between the strain information and the risk of revision. Therefore, the risk of UKA revision can be predicted by this integrated model. RESULTS: Leave-one-out (LOO) cross-validation (CV) is implemented to assess the prediction accuracy. As a result, the mean prediction accuracy is 93.58% for all these cases, demonstrating the high value of this model as a decision-making assistant for surgical plaining of knee OA. CONCLUSIONS: The results of this study demonstrated that this integrated model can predict the risk of UKA revision with theoretically high accuracy. It combines bio-mechanical and statistical learning approach to create a surgical planning tool which may support clinical decision in the future.

Cognitive function and retinal and ischemic brain changes: the Women's Health Initiative.

OBJECTIVE: To examine the association between retinopathy and cognitive decline or brain lesions and volumes in older women. METHODS: This study included 511 women aged 65 and older who were simultaneously enrolled in the Women's Health Initiative Memory Study and the Sight Examination Study. In this analysis, we examined the link between retinopathy, assessed using fundus photography (2000-2002), cognitive performance over time assessed by the modified Mini-Mental State Examination (3MSE) (1996-2007), and white matter hyperintensities and lacunar infarcts in the basal ganglia. RESULTS: Presence of retinopathy was associated with poorer 3MSE scores (mean difference = 1.01, SE: 0.43) (p = 0.019) over a 10-year follow-up period and greater ischemic volumes in the total brain (47% larger, p = 0.04) and the parietal lobe (68% larger, p = 0.01) but not with measures of regional brain atrophy. CONCLUSIONS: The correspondence we found between retinopathy and cognitive impairment, along with larger ischemic lesion volumes, strengthens existing evidence that retinopathy as a marker of small vessel disease is a risk factor for cerebrovascular disease that may influence cognitive performance and related brain changes. Retinopathy may be useful as a clinical tool if it can be shown to be an early marker related to neurologic outcomes.

Combining graph and machine learning methods to analyze differences in functional connectivity across sex.

In this work we combine machine learning methods and graph theoretical analysis to investigate gender associated differences in resting state brain network connectivity. The set of all correlations computed from the fMRI resting state data is used as input features for classification. Two ensemble learning methods are used to perform the detection of the set of discriminative edges between groups (males vs. females) of brain networks: 1) Random Forest and 2) an ensemble method based on least angle shrinkage and selection operator (lasso) regressors. Permutation testing is used not only to assess significance of classification accuracy but also to evaluate significance of feature selection. Finally, these methods are applied to data downloaded from the Connectome Project website. Our results suggest that gender differences in brain function may be related to sexually dimorphic regional connectivity between specific critical nodes via gender-discriminative edges.

Videoenteroscopia de balón único con prototipo Olympus: experiencia preliminar / Single-balloon videoenteroscopy olympus prototype: preliminary experience

Introducción: La enteroscopia de balón único es una técnica segura con alto alcance diagnóstico y terapéutico. Sin embargo, existe la dificultad para el manejo de accesorios mientras mayor es la profundidad de inserción. Objetivo: Mostrar ventajas en el diagnóstico y tratamiento de patología del intestino delgado utilizando un prototipo Olympus con canal 3,2 mm. Pacientes y métodos: 18 procedimientos en 13 pacientes. Diciembre 2009-Abril 2010. Se utilizó el prototipo Olympus X SIF 180 JY, con canal 3.2 mm y canal externo de irrigación. Se usaron accesorios endoscópicos de tecnología convencional para colonoscopia. Se registraron datos demográficos, indicaciones, vía de acceso, tiempo del procedimiento, profundidad de inserción, hallazgos y terapéutica. Resultados: 13 pacientes: 9 femenino, 4 masculino, edad promedio: 47,61 años. Indicaciones principales: sangrado digestivo oscuro (4), Diarrea crónica (4), síndrome de poliposis (3). Procedimientos. Vía anterógrada 13, retrógrada 4, combinado 1. Tiempo promedio: 40,46 minutos anterógrada, 36,35 minutos retrógrada. Profundidad de inserción: 201,53 cm anterógrada, 95 cm retrograda. Estudio normal: 46,15 % de los pacientes, hallazgos positivos: 53,84%. Terapéutica: 5 (27,7%): clips (2), inyección con adrenalina+argón (1), polipectomía (1), dilatación de estenosis (1). No hubo complicaciones. Conclusión: el prototipo Olympus X SIF 180 JY cuenta con canal terapéutico que permite la utilización de accesorios endoscópicos de tecnología convencional con menor dificultad de deslizamiento a mayor profundidad de inserción y canal de irrigación externo que mejora la visibilidad del campo. Ambas características favorecerían la realización de procedimientos terapéuticos.

Introduction: The single balloon enteroscopy is a safe technique with high diagnostic and therapeutic yield. However, there is the difficulty to manage attachments while the greater the depth of insertion. Objective: To show benefits in the diagnosis and treatment of diseases of the small bowel using a prototype Olympus with 3.2 mm channel. Patients and Methods: 18 procedures in 13 patients. December 2009-April 2010. We used the prototype Olympus SIF 180 JY X, with 3.2 mm channel and external canal irrigation. Standard endoscopic accessories were used for colonoscopy. Recorded demographic data, indications, route of access, procedure time, insertion depth, and therapeutic findings. Results: 13 patients: 9 women, 4 men, mean age: 47.61 years. Main indications: obscure gastrointestinal bleeding (4), chronic diarrhea (4), polyposis syndrome (3). Procedures. 13 antegrade, 4 retrograde, combined 1. Average Time: 40.46 minutes antegrade, retrograde 36.35 minutes. Depth of insertion: 201.53 cm antegrade, retrograde 95 cm. Study normal: 46.15% of patients, positive findings: 53.84%, with active bleeding lymphangioma (1), Dieulafoy lesion (1), celiac disease (1), Crohn's (1), polyposis (3). Therapeutics 5 (27.7%) clips (2), adrenaline injection + argon (1), polypectomy (1), dilatation of stenosis (1). There were no complications. Conclusion: The prototype Olympus SIF 180 JY X has therapeutic channel allows the use of standard endoscopic accessories more easily slip deeper insertion and external irrigation canal which enhances the visibility of the field. Both features favor the therapeutic procedures.

Endocápsula olympus: reporte inicial de su uso en Venezuela / Endocápsula olympus: initial report of its use in Venezuela

Introducción: En 2001 se introdujo la cápsula endoscópica de Given Imaging® como un método no invasivo que permite realizar enteroscopia total. Recientemente Olympus® desarrolló una cápsula endoscópica para intestino delgado con características diferentes en el sistema óptico, tiempo de carga de batería, tiempo de grabación y descarga de imágenes, además de contar con un sistema que monitorea en tiempo real la localización de la cápsula. Objetivo: Reportar la experiencia inicial con la Endocápsula Olympus® en Venezuela. Pacientes y métodos: De julio a septiembre de 2009 se evaluaron 24 pacientes con sospecha de patología del intestino delgado con este dispositivo. Se registraron datos demográficos, indicación del procedimiento, tiempo de pase gástrico, intestinal, hallazgos y complicaciones. Resultados: 24 pacientes: 11 masculinos y 13 femeninos. Las principales indicaciones fueron: sangrado digestivo oscuro (n=15) y diarrea crónica (n=4). El tiempo gástrico promedio fue de 71,03 + SD minutos y el intestinal de 267,9 + SD minutos. En 1 paciente la cápsula se colocó con el gastroscopio y en 3 no alcanzó el ciego (12,5%). En 11 casos el estudio fue normal (45,83%). Hubo hallazgos positivos en 13 (54,16%): angiectasias (n=6), enfermedad celiaca (n=1), tumor subepitelial ulcerado (n=1), intususcepción (n=1), sangre roja en ileon (n=1), erosiones (n=1), linfangiectasia (n=2). El 84,61% de los hallazgos se relacionaba con la indicación. No hubo complicaciones. Conclusión: La Endoscápsula Olympus® es útil en la evaluación del intestino delgado con un alcance diagnóstico similar al reportado en la literatura para la Cápsula de Given Imaging®. El menor tiempo requerido para cargar la batería, descargar imágenes y el sistema de tiempo real, la convierte en una alternativa para su uso en patología urgente. Estudios prospectivos comparativos son necesarios.

Introduction: In 2001, the Given Imaging® endoscopic capsule was introduced as a noninvasive method that allows total enteroscopy. Olympus® recently developed a small bowel capsule endoscopy with different characteristics in the optical system, battery charging time, recording and image download times, in addition to a system that monitors real-time location of the capsule. Objective: To report the initial experience with Olympus® Endocapsule in Venezuela. Patients and methods: 24 patients with suspected small bowel pathology were evaluated between July and September 2009 using Olympus® Endocapsule. Demographic data, indication for the procedure, gastric time pass, intestinal transit, findings and complications were recorded. Results: 24 patients: 11 male and 13 female. The main indications were obscure gastrointestinal bleeding (n = 15) and chronic diarrhea (n = 4). The average gastric time was 71.03 + SD minutes and intestinal time was 267.9 + SD minutes. In 1 patient the capsule was placed with the gastroscope and in 3 it did not reach the cecum (12.5%). In 11 cases the study was normal (45.83%). There were positive findings in 13 (54.16%) angiectasias (n=6), celiac disease (n=1), subepithelial ulcerated tumor (n=1), intussusception (n 1), red blood in the ileum (n=1), erosions (n=1), lymphangiectasia (n=2). 84.61% of the findings were related to the indication. There were no complications. Conclusion: The Olympus® Endocapsule is useful for diagnosis of small intestine and has a diagnostic yield similar to that reported in the literature for the Given Imaging videocapsule. The shorter time required for charging the battery, download images and the real time system, makes it an alternative for using in emergency conditions. Comparative prospective studies are needed.

Capsula endoscópica y enteroscopia asistida por balones en pacientes con sospecha de enfermedad de intestino delgado métodos complementarios / Capsule endoscopy and balloon enteroscopy in patients with suspected small bowel disease complementary methods

El desarrollo reciente de la cápsula endoscópica (CE) y la enteroscopia asistida por balones (EAPB) ha cambiado el algoritmo diagnóstico de la patología del intestino delgado. La combinación de ambos métodos parece ser una herramienta útil. Mostrar la experiencia con el uso combinado de CE y EAPB en pacientes con sospecha de enfermedades del intestino delgado. 34 pacientes a quienes se les realizó CE y EAPB. El endoscopista conocía el resultado de la CE. Equipos: CE M2A, PillCam SB (Given Imaging), videoenteroscopios doble balón Fujinon EN-450P5, EN-450T5, enteroscopio balón único Olympus SIG Q-180. Se registraron datos demográficos, indicaciones, segmentos evaluados, hallazgos y complicaciones. 34 pacientes (19 mujeres, 15 hombres), edad promedio: 57,67 años. Principales indicaciones: sangrado digestivo oscuro evidente 67,64 %, anemia 11,76%, enfermedad de Crohn 5,88%. La EAPB se realizó por vía anterógrada en 25 pacientes, retrógrada en 4 y combinada en 5. Se detectaron lesiones con CE en 85,29% pacientes, con EAEAPB en 67,64% y con ambos métodos en 52,9%. En 11 pacientes se detectaron lesiones por CE y la EAPB fue normal. En 2 pacientes hubo hallazgos en la EAPB no vistos por la cápsula. Hallazgos mas frecuentes: CE: angioectasias 11, tumor subepitelial ulcerado 2, presencia de sangre 4, úlceras 3. EAPB: angioectasias 9, tumor subepitelial ulcerado 1, ulceras 3, divertículo de Meckel, 1. Terapéutica endoscópica en 13 pacientes y cirugía en 4 con sangrado digestivo. CE y EBU combinadas permiten mejorar el diagnóstico y orientar la conducta terapéutica en pacientes con sospecha de patología del intestino delgado...

The recent development of capsule endoscopy (CE) and balloon-assisted enteroscopy (BAE) has changed the diagnostic algorithm of small bowel pathology. The combination of both methods seems to be a useful tool. To show the experience with the combined use of CE and BAE in patients with suspected small bowel diseases. 34 patients who underwent CE and BAE. The endoscopist knew the outcome of the CE. We used the CE M2A, Pillcam (Given Imaging), double balloon videoenteroscopy Fujinon EN-450P5, EN-450T5, single balloon enteroscopy GIS Olympus Q-180. Demographic data, indications, segments evaluated, findings and complications were recorded. 34 patients (19 women, 15 men), average age: 57.67 years. Main indications: evident obscure gastrointestinal bleeding 67.64%, anemia 11, 76%, Crohn’s disease 5.88%. Anterograde BAE was performed in 25 patients, retrograde in 4 and combined in 5 patients. CE lesions were detected in 85.29% patients with BAE in 67.64% and 52.9% in both methods. In 11 patients lesions were detected by CE and the BAE was normal. In 2 patients there were findings in the BAE, not seen by the capsule. Most common finding: CE: 11 angiodysplasia, 2 subepithelial ulcerated tumor, 4 blood presence, 3 ulcers. BAE: 9 angiodysplasia, 1 subepithelial ulcerated tumor, 3 ulcers, 1 Meckel diverticulum. Therapeutic endoscopy was performed in 13 patients and surgery in 4 patients with digestive bleeding. Combined CE and BAE allow improving the diagnostic and orientate the therapeutic behavior in patients with suspected small bowel pathology...

8 años de cápsula endoscopica: progresos y retos / 8 years of capsule endoscopy: progresses and challenges

Desde su introducción en el año 2001, la cápsula endoscópica (CE) ha cambiado el diagnóstico y manejo de la patología del intestino delgado. Evaluar la utilidad clínica de la CE en pacientes con sospecha de enfermedad de intestino delgado. Pacientes a quienes se les realizó CE desde octubre 2001 hasta abril 2009 en dos centros médicos: La Policlínica Metropolitana y el Centro Médico de Caracas. Cápsulas utilizadas: M2A y PillCam SB (Given Imaging). Se registraron datos demográficos, indicaciones, vaciamiento gástrico y tránsito intestinal, hallazgos y complicaciones. 339 pacientes, 180 hombres-159 mujeres. Edad promedio: 56,04 años. Indicaciones: hemorragia digestiva oscura (n=217), diarrea crónica (n=22), enfermedad de Crohn (20), búsqueda de tumores (n=30), dolor abdominal (n=29), enfermedad celíaca (n=5), misceláneos (n=16). Se encontraron lesiones en 78,8% de los pacientes. Hallazgos: angiectasias 28,3%, erosiones 28,6%, úlceras 12,5%, sangrado activo 8% y tumores subepiteliales 4,2%. Al correlacionar los hallazgos con las indicaciones se encontró un porcentaje de concordancia significativo en pacientes con hemorragia digestiva oscura y enfermedad de Crohn. Complicaciones: obstrucción intestinal (n=1), retención (n=6). La CE es un método mínimamente invasivo, bien tolerado, con pocas complicaciones y porcentaje elevado de detección de lesiones, que parece posicionarse para guiar el diagnóstico y tratamiento de patologías como el sangrado digestivo oscuro y la enfermedad de Crohn. Pudimos adaptarnos a la plataforma tecnológica como usuarios y prepararnos para los nuevos avances que se avecinan, creemos que es el momento para dar inicio a un programa de entrenamiento en CE...

Since its introduction in 2001, the endoscopic capsule (EC) has changed the diagnosis and management of small bowel pathology. Objective: To evaluate the clinical benefi t of EC in patients with suspected small bowel disease. Patients who underwent EC from October 2001 to April 2009 at two medical centers, Policínica Metropolitana and Centro Médico de Caracas. Capsules used: M2A and PillCam SB (Given Imaging). Demographic data, indications, gastric emptying and intestinal transit, as well as, fi ndings and complications were recorded. 339 patients, 180 men, 159 women. Average age: 56.04 yearsold. Indications: obscure gastrointestinal bleeding (n = 217), chronic diarrhea (n = 22), Crohn’s disease (n=20), tumor screening (n = 30), abdominal pain (n = 29), celiac disease (n = 5), miscellaneous (n = 16). Lesions were found in 78.8% of patients. Findings: angiectasias 28.3%, erosions 28.6%, ulcers 12.5%, active bleeding 8% and, subepithelial tumors 4.2%. By correlating the fi ndings with the indications we found a signifi cant percentage of concordance in patients with obscure gastrointestinal bleeding and Crohn’s disease. Complications: intestinal obstruction (n=1), retention (n=6). EC is a minimally invasive well tolerated method, with few complications and high percentage of lesions detection, which seems to be positioned to guide the diagnosis and therapy of disorders such as, obscure gastrointestinal bleeding and Crohn’s disease. We were able to adapt to the technological platform as users and prepare for new developments to come; we believe it is time to begin a training program in EC...

Evaluating the impact of spatio-temporal smoothness constraints on the BOLD hemodynamic response function estimation: an analysis based on Tikhonov regularization.

Recently we have proposed the use of Tikhonov regularization with temporal smoothness constraints to estimate the BOLD fMRI hemodynamic response function (HRF). The temporal smoothness constraint was imposed on the estimates by using second derivative information while the regularization parameter was selected based on the generalized cross-validation function (GCV). Using one-dimensional simulations, we previously found this method to produce reliable estimates of the HRF time course, especially its time to peak (TTP), being at the same time fast and robust to over-sampling in the HRF estimation. Here, we extend the method to include simultaneous temporal and spatial smoothness constraints. This method does not need Gaussian smoothing as a pre-processing step as usually done in fMRI data analysis. We carried out two-dimensional simulations to compare the two methods: Tikhonov regularization with temporal (Tik-GCV-T) and spatio-temporal (Tik-GCV-ST) smoothness constraints on the estimated HRF. We focus our attention on quantifying the influence of the Gaussian data smoothing and the presence of edges on the performance of these techniques. Our results suggest that the spatial smoothing introduced by regularization is less severe than that produced by Gaussian smoothing. This allows more accurate estimates of the response amplitudes while producing similar estimates of the TTP. We illustrate these ideas using real data.

A hydrodynamic model of labyrinth to study the stimulation of perilymph compartments by audioprostheses.

CONCLUSIONS: The hydrodynamic model of the labyrinth spaces (LHM) is a useful tool for research on implantable audioprostheses, in particular to develop suitable actuators using MEMS technology (micro-electromechanic machine system). It has other potential applications for auditory research. OBJECTIVES: The energy reaching the labyrinth fluids is crucial information for developing prostheses to substitute the tympanic-ossicular system because adequate stimulation of the cochlear partition is essential. However, in vivo measurements in human ears are not currently available. Therefore a model of the normal labyrinth resembling its hydrodynamic properties becomes a valuable tool. It could allow comparison of different processing systems, algorithms and transducers, to develop new audioprostheses and improve their effectiveness and efficiency. MATERIALS AND METHODS: This work presents one LHM that emulates the conduction of the stimuli from the stapes footplate through the labyrinthine fluids, including its dimensions and physical properties, and some examples of measurements of perilymph stimulation by different audioprostheses and algorithms. RESULTS. As shown in the reported examples, this LHM provided effective measurement of acoustic stimulation across the whole human auditory frequency and intensity spectrum. Air-delivered and direct stimulation methods are possible. This provided convenient information for the actuator development and allowed comparison between different prototypes, stimulation patterns and algorithms.

Estimation of false discovery rates for wavelet-denoised statistical parametric maps.

Correction for multiple comparisons in neuroimaging data is an important area of research. Recently, wavelet-based methods have gained popularity and have been reported to achieve better sensitivity compared to spatial domain methods. However, these techniques produce smoothed statistical maps which are difficult to interpret. The generated maps have to be thresholded again in the spatial domain to delineate active from inactive regions. The selection of a proper threshold satisfying the required error rate control is not straightforward. In this paper, a framework is proposed for thresholding wavelet-denoised maps in which a rejection region is fixed, and the achieved false discovery rate (FDR) is estimated. This approach provides a meaningful strategy to choose thresholds for wavelet-denoised statistical parametric maps (SPMs). Two FDR estimation algorithms were used to assess the achieved error rate control when thresholding wavelet filtered SPMs at various rejection regions. Their performance was evaluated using both simulated and resting fMRI data. The proposed framework was also applied on in vivo data.

FACO/LUZ: hacia la construcción de un modelo educativo integral en odontología (parte I) / FACO/LUZ: towards the construction of an integred educational model in dentistry (part I)

Construir un modelo educativo integral que de respuesta a los retos de la odontología como ciencia comprometida socialmente, tanto en el contexto nacional como latinoamericano. Parte de algunas consideraciones que develan los principios y las políticas del Estado que rigen la educación superior en el mundo contemporáneo. Para la construcción de la propuesta, la Facultad de Odontología de la Universidad del Zulia, FACO/LUZ, dio apertura a escenarios de discusión con la participación de los actores involucrados en el proceso, con la finalidad de evaluar la experiencia institucional en materia curricular. Igualmente, realizó un análisis crítico de las tendencias mundiales en educación y salud, a objeto de incorporarlas a la propuesta. En sus alcances el modelo posibilita la formación de talento humano cuya praxis apunte a la transformación cuali-cuantitativa, de la situación de salud bucal de la población. En su marco filosófico reafirma el modelo educativo docencia-servicio-investigación e inserta conceptos actuales relacionados con la bioética, transculturalidad, la epidiscipilinariedad y el uso de las lenguas autóctonas de la región y el país. Finalmente, el modelo permite integrar la teoría y la práctica (estudio-trabajo) en el marco de la estratégia de la atención primaria en salud.

Plan de estudios: integración del eje de práctica odontológica / Study plan: the integration of dentistry practice

Determinar la integración de los conocimientos bio-psico-sociales con el eje de la Práctica Odontológica del Diseño Curricular 1995 de la facultad de Odontología de la Universidad del Zulia (FACO/LUZ). La muestra estuvo conformada por los cuatro programas del eje de práctica Odontológica y los objetivos generales de los 33 programas de las asignaturas del Diseño Curricular. Para evaluar el grado de integración, se construyeron instrumentos en forma de matrices, lo cual permitió realizar el análisis de contenido, dichos instrumentos fueron aplicados a 11 Odontólogos especialistas en Educación y Planificación. Se obtuvo una mediana integración del Eje de Practica Odontológica con las asignaturas de formación general (59,17 por ciento), y una adecuada integración con la formación (61,17 por ciento) y formación específica (74,27 por ceinto). El eje de Práctica Odontológica hace énfasis en el nivel tecnológico debido a que mayor relación encontrada fue en la formación profesional específica. Se recomienda que se continúe trabajando en la conexión del Eje con las asignaturas del plan de estudio, lo cual redundaría en la consolidación de la integración y un fortaleciemiento del modelo educativo de docencia-servicio-investigación asumido por la FACO/LUZ.

MIT image reconstruction based on edge-preserving regularization.

Tikhonov regularization has been widely used in electrical tomography to deal with the ill-posedness of the inverse problem. However, due to the fact that discontinuities are strongly penalized, this approach tends to produce blurred images. Recently, a lot of interest has been devoted to methods with edge-preserving properties, such as those related to total variation, wavelets and half-quadratic regularization. In the present work, the performance of an edge-preserving regularization method, called ARTUR, is evaluated in the context of magnetic induction tomography (MIT). ARTUR is a deterministic method based on half-quadratic regularization, where complementary a priori information may be introduced in the reconstruction algorithm by the use of a nonnegativity constraint. The method is first tested using an MIT analytical model that generates projection data given the position, the radius and the magnetic permeability of a single nonconductive cylindrical object. It is shown that even in the presence of strong Gaussian additive noise, it is still able to recover the main features of the object. Secondly, reconstructions based on real data for different configurations of conductive nonmagnetic cylindrical objects are presented and some of their parameters estimated.

Niveles de apoproteina-B Y LDL-colesterol en una población joven de la ciudad de Maracaibo / Apolipoprotein-B and LDL-cholesterol levels in a young group of Maracaibo

El presente estudio se propuso determinar si las concentraciones de apoproteína-B (g/L) se correlacionan con el LDL-colesterol (mg/dL) y al mismo tiempo, investigar la posibilidad de aplicarias a la poblaci¢n de Maracaibo, en substitución de la fórmula de Friedewald de LDL-Colesterol. Las concentraciones séricas de la apoproteína-B fueron estudiadas en una muestra de 41 sujetos (27 hombres y 14 mujeres) con edades entre 20 y 39 anos, usuarios del Laboratorio Clínico de la Escuela de Bio nalisis de La Universidad del Zulia, de la ciudad de Maracaibo. Se realizaron mediciones de glicemia, colesterol total, triacilglicéridos y el cálculo de LOL-C. La apoproteína-B fue determinada por un método inmunoturbidimétrico. Los valores de apoproteína-B‘+ OU –‘ OS fueron de 0.93 ‘+ OU –‘ 0.3 g/L en el sexo femenino y de 1.06 ‘+ OU –‘ 0.31 g/L en el sexo masculino. La correlación entre la apoproteína-B y el LDL-C fue de 0.8640. Al aplicar el an lisis de regresión linear se obtuvieron fórmulas para el c lculo del LCL-C a partir de la concentración de apoproteína-B, representando un c lculo estadístico que deber ser corroborado de manera experimental. El valor de riesgo de apoproteína -B + 1.2 g/L se ubicó en las percentiles 95 th para el sexo femenino y 75 th para el masculino

Autoimmune hepatitis in African Americans: presenting features and response to therapy.

OBJECTIVES: African Americans are at an increased risk for certain diseases and more frequently suffer complications of those diseases relative to their white counterparts. Most studies of autoimmune hepatitis consist of entirely white populations. The Emory University system of hospitals serves a large African American population, including a significant number of African Americans with autoimmune hepatitis. The goal of this study was to determine if the presentation and response to therapy in African Americans is, like other diseases, different than in whites. METHODS: This is a retrospective study from a tertiary referral center that examines the initial presenting features and response to therapy of African Americans (n = 27) and whites (n = 24) with autoimmune hepatitis. RESULTS: Eighty-five percent of African Americans had cirrhosis on the initial liver biopsy, as compared with 38% of whites. Although not statistically significant, the African Americans presented at an earlier age than white patients. The disease also appeared more advanced in African Americans, as bilibubin levels tended to be higher, but not significantly, and PTs were more prolonged. Both groups responded well to therapy, with significant falls in serum levels of AST, ALT, and bilirubin. Fifty percent of African Americans and 48% of whites entered a biochemical remission. The amount of prednisone required to maintain remission at follow-up was greater in African Americans. CONCLUSION: In contrast to whites, the majority of African Americans present with cirrhosis. Despite the high prevalence of cirrhosis, the response to therapy is good. However, more immunosuppression is required to control the disease in African Americans.