Evaluation of Alternative Refractory Materials for the Main Flame Deflectors at KSC Launch Complexes

The deterioration of the refractory materials used to protect the KSC launch complex steel base structures from the high temperatures during launches results in frequent and costly repairs and safety hazards. KSC-SPEC-P-0012, Specification for Refractory Concrete, is ineffective in qualifying refractory materials. This study of the specification and of alternative refractory materials recommends a complete revision of the specification and further investigation of materials that were found to withstand the environment of the Solid Rocket Booster main flame deflector better than the refractory materials in current use in terms of compressive strength, tensile strength, modulus of rupture, shrinkage, and abrasion

Incidencia de QT corto y largo en alumnos de primer ingreso a Facultad de Deportes

Las alteraciones electrocardiográficas del intervalo QT (síndrome de QT corto y largo) están asociadas a un riesgo elevado de muerte súbita por arritmias ventriculares malignas y a episodios de fibrilación auricular. Por ello el objetivo de este estudio fue detectar la incidencia de alteraciones en el intervalo QT del electrocardiograma en reposo en alumnos de primer ingreso de la Facultad de Deportes periodo 2015-2. Mediante un diseño descriptivo transversal participaron 78 alumnos de ambos géneros (59 hombres, 19 mujeres) quienes ingresaron a la carrera de Licenciatura. Tuvieron una edad promedio de 20 (M = 3.58) años, a quienes se les realizó un electrocardiograma en reposo, y se midió el intervalo QT, intervalo RR, y se obtuvo el QT corregido. Los datos se analizaron descriptivamente mediante tablas de frecuencias. Los resultados ofrecieron evidencia de las alteraciones electrocardiográficas del intervalo QT corregido en el 5.12% de la muestra, en un caso con un QT corto (306 ms) y el resto de los casos con un QT largo (459 ms). Se concluye que la incidencia de alteraciones del intervalo QT en los alumnos de primer ingreso de la Facultad de Deportes 2015-2 campus Mexicali es baja, no obstante merece atención porque tal alteración se asocia a la predisposición de episodios de muerte súbita cardiaca. ABSTRACT The short QT syndrome is associated with an increased risk of sudden death due to malignant ventricular arrhythmias and atrial fibrillation episodes. The aim of this study was to detect the incident of alterations in QT interval of the electrocardiogram in freshmen entering to the Facultad de Deportes 2015-2. By a transverse descriptive design seventy-eight students were evaluated (59 men, 19 women), for who 20 years old average (SD = 3.58). Arresting electrocardiogram was measured QT interval, RR interval and corrected QT was obtained. Data were proceeded to be analyzed descriptively using frequency tables. The results evidence showed an electrocardiographic abnormalities like a corrected QT in 5.12%, one case of a Short QT (306 ms) and the other with a long QT (459 ms). As a conclusion the incident of QT alteration in freshmen of the Facultad de Deportes 2015-2 campus Mexicali is low: However, it worth attention because we can prevent a sudden cardiac death whiles themis practicing Activity Physic

Performance Assessment of Refractory Concrete Used on the Space Shuttle's Launch Pad

The John F. Kennedy Space Center (KSC) maintains several facilities for launching space vehicles. During recent launches it has been observed that the refractory concrete materials that protect the steel-framed flame duct are breaking away from this base structure and are being projected at high velocities. There is significant concern that these projected pieces can strike the launch complex or space vehicle during the launch, jeopardizing the safety of the mission. A qualification program is in place to evaluate the performance of different refractory concretes and data from these tests have been used to assess the performance of the refractory concretes. However, there is significant variation in the test results, possibly making the existing qualification test program unreliable. This paper will evaluate data from past qualification tests, identify potential key performance indicators for the launch complex, and will recommend a new qualification test program that can be used to better qualify refractory concrete

Lactobacillus strains inhibit biofilm formation of Salmonella sp. isolates from poultry

Lactic acid bacteria (LAB)exert a strong antagonistic activity against many microorganisms including food spoilage organisms and may be used as an alternative to control biofilm formation of pathogens in food industries. The objective of this work was to investigate the ability of fifteen Salmonella strains isolated from poultry environment to form biofilms on different surfaces. In addition, the effect of Lactobacillus kefiri strains 8321 and 83113 and Lactobacillus plantarum 83114 and their surface proteins on biofilm development of Salmonella Enteritidis 115 was studied. The relationship between surface properties of bacteria (hydrophobicity, autoaggregation and coaggregation with lactobacilli)and biofilm formation was also investigated. Most of Salmonella strains were hydrophilic and five strains were moderately hydrophobic. In general, Salmonella strains showed high aggregation abilities (27?54%). S. Enteritidis 106 and S. Typhimurium 102 and 108 showed the highest percentages of autoaggregation. All Salmonella strains tested showed aggregation abilities with the three lactobacilli studied, but the percentage of coaggregation proved to be strain-specific. When comparing stainless steel, glass and polystyrene surfaces, higher levels of biofilm formation occurred on polystyrene plate than on glass surfaces or stainless steel. S. Enteritidis 115 exhibited the greatest attachment to polyestyrene surface. The preincubation or coincubation with the three lactobacilli strains significantly reduced (about 1 log CFU/ml of reduction)the ability of S. Enteritidis 115 to form biofilm compared to the control without lactobacilli. These results were confirmed by confocal microscopy. In the same way, when surface proteins extracted from lactobacilli strains were preincubated or coincubated with S. Enteritidis 115, biofilm formation of this strain was significantly decreased compared to the control. The results obtained showed that these Lactobacillus strains and their surface proteins can be used as alternatives for control of biofilm formation by Salmonella in the poultry industry.Fil: Merino, Lina Ethel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Trejo, Fernando Miguel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: de Antoni, Graciela Liliana. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Microbiología General; ArgentinaFil: Golowczyc, Marina Alejandra. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Psychological aspects of pre-adolescents or adolescents with precocious puberty: A systematic review

Precocious puberty (PP) is an illness that appears when puberty, begins some years earlier than usual, provoking inferences in preadolescents and adolescents and their families. Therefore, the aim is to analyze if psychological consequences can be observed in groups of preadolescents or adolescents with PP. Method: A bibliographic search of the scientific literature was made following the PRISMA guide in the following databases: ProQuest, Psychinfo, Web Of Science, and Scopus. 592 studies were found, were uploaded to Covidence to make a screening, of which finally 6 were included for the revision according to the inclusion and exclusion criteria. Two independent evaluators made the search, selection, data extraction and quality evaluation of studies independently. The agreement degree between both was excellent in all of the cases. Results: 211 preadolescents participated in total in all studies, of which 99 were preadolescents with PP, with a mean age of 8,94 years old. Studies evaluated so heterogeneous variables, such as psychopathology, selfimage, neuropsychological and cognitive variables, and reasons to delay or stop PP. The quality of studies was moderated especially due to the low quality of the studies design, which were mostly transversal, and the representativity of the sample, being selected by convenience. Conclusions and implications: More research is needed to evaluate the psychological consequences of the PP diagnosis in pediatrics, and its protection factors, because none of the studies approached this question. We consider that it is necessary to increment the quality of these studies, and that these take a biopsychosocial perspective

Albumin excretion in olders with and without MetS in exercise

INTRODUCTION: Exercising modifies renal function such as decreased kidney circulation and glomerular filtration in healthy conditions. In young and adults microalbuminuria could be induced by strenuous exercise however the effects of maximal and submaximal exercise on microalbuminuria in elderly (≥65 years) are not well known. We evaluated the effect of different intensities of acute exercise on microalbuminuria in elderly. PURPOSE: We evaluated the effect of different intensities of acute exercise on microalbuminuria in elderly. METHODS: The study involved 20 subjects, 13 men and 7 women (70 ± 5 years-old); they performed 3 bicycle exercise test a week apart of each other: maximal physical exercise (Maxcap-B), and two submaximal tests (Submax-B 80% and Submax-B 60%). In the first session after a 10 h fast, a blood sample was taken to determine serum glucose, creatinine, uric acid, cholesterol and triglycerides and clinical record and basal electrocardiogram and BMI (kg/m2) were also obtained. Urine samples were collected before, immediately after, one hour and 24 hours after exercise to determine microalbuminuria (cutoff, 20-200 mg/l). RESULTS: Healthy old adults were 4 male, the rest of the sample bear metabolic syndrome (MetS). Transient microalbuminuria was observed immediately after all three exercise tests, and 1 hour post-exercise in all individuals; however, it was higher in those with MetS. After 24 hours of exercise, no microalbuminuria was detected. CONCLUSION: Conclusion: The maximal and submaximal exercise (Submax-B 80% and Submax-B 60%) transiently affected renal function in old adults, more importantly in those with metabolic syndrome

Versión en español de la subescala presión del entrenador del MIPS: Propiedades psicométricas

La subescala “presión del entrenador” del Multidimensional Inventory or Perfectionism in Sport, mide las tendencias de los deportistas de percibir a sus entrenadores como fuentes de presión para obtener cierto nivel de rendimiento perfecto. El propósito de este estudio fue traducir al español hablado en México los ocho ítems de la subescala presión del entrenador, y examinar sus propiedades psicométricas (validez factorial, fiabilidad, validez convergente, validez de criterio). Participaron 106 deportistas de ambos sexos con una edad promedio de 12.5 años (DT=1.72). El análisis factorial confirmatorio apoyó la estructura unifactorial, donde seis de los ocho ítems fueron válidos para medir el factor latente. La fiabilidad demostró fuerte consistencia interna; y la presión del entrenador se relacionó positivamente con el miedo a fallar, mostrando el patrón de correlación esperada. En conclusión, esta adaptación es válida y confiable tras la eliminación de dos ítems, y puede ser utilizada en la investigación dentro del contexto deportivo mexicano

Biofilm formation by <i>Salmonella</i> sp. in the poultry industry: Detection, control and eradication strategies

Salmonella represents an important global public health problem and it is an emerging zoonotic bacterial threat in the poultry industry. Diverse registered human cases of salmonellosis shown poultry origins. Various control measures have been employed both at the farming and processing levels to address it. This review focuses on traditional and new detection techniques of biofilm formation by Salmonella spp. and different approaches that can be used to prevent and/or control biofilm formation by these bacteria. A number of methodologies based on different approximations have been recently employed to detect and evaluate bacteria attached to surfaces, including real-time polymerase chain reaction (PCR), confocal laser scanning microscopy and Optical Coherence Tomography. Due to persistence of Salmonella biofilm in food processing environments after cleaning and sanitation, control and eradication strategies in poultry industry should be constantly studied. In this sense, the use of several alternatives to control Salmonella biofilm formation, such as lactic acid bacteria, phagetherapy, extracts from aromatic plants, quorum sensing inhibitors, bacteriocins and nanomaterials, have been successfully tested and will be reviewed.Facultad de Ciencias ExactasCentro de Investigación y Desarrollo en Criotecnología de Alimento

Breast Dense Tissue Segmentation with Noisy Labels: A Hybrid Threshold-Based and Mask-Based Approach

Breast density assessed from digital mammograms is a known biomarker related to a higher risk of developing breast cancer. Supervised learning algorithms have been implemented to determine this. However, the performance of these algorithms depends on the quality of the ground-truth information, which expert readers usually provide. These expert labels are noisy approximations to the ground truth, as there is both intra- and inter-observer variability among them. Thus, it is crucial to provide a reliable method to measure breast density from mammograms. This paper presents a fully automated method based on deep learning to estimate breast density, including breast detection, pectoral muscle exclusion, and dense tissue segmentation. We propose a novel confusion matrix (CM)-YNet model for the segmentation step. This architecture includes networks to model each radiologist's noisy label and gives the estimated ground-truth segmentation as well as two parameters that allow interaction with a threshold-based labeling tool. A multi-center study involving 1785 women whose "for presentation" mammograms were obtained from 11 different medical facilities was performed. A total of 2496 mammograms were used as the training corpus, and 844 formed the testing corpus. Additionally, we included a totally independent dataset from a different center, composed of 381 women with one image per patient. Each mammogram was labeled independently by two expert radiologists using a threshold-based tool. The implemented CM-Ynet model achieved the highest DICE score averaged over both test datasets (0.82±0.14) when compared to the closest dense-tissue segmentation assessment from both radiologists. The level of concordance between the two radiologists showed a DICE score of 0.76±0.17. An automatic breast density estimator based on deep learning exhibited higher performance when compared with two experienced radiologists. This suggests that modeling each radiologist's label allows for better estimation of the unknown ground-truth segmentation. The advantage of the proposed model is that it also provides the threshold parameters that enable user interaction with a threshold-based tool.This research was partially funded by Generalitat Valenciana through IVACE (Valencian Institute of Business Competitiveness) distributed by nomination to Valencian technological innovation centres under project expedient IMDEEA/2021/100. It was also supported by grants from Instituto de Salud Carlos III FEDER (PI17/00047).S