133 research outputs found
Preparação de dioxolanos: estudo comparativo de reações realizadas em microondas e em aquecimento convencional
TCC (graduação) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Curso de Química.Este trabalho relate a preparação de dioxolanos, usualmente preparados a partir de um composto carbonilico com excesso de etilenoglicol. em refluxo com benzeno, na presença de um acido catalisador. A agua removida do meio reacional com auxilio de um Dean-Stark. Foi feito um estudo comparativo dessas reações conduzidas sob aquecimento convencional e sob microondas, com o objetivo de se verificar qual o efeito das microondas sobre a velocidade de reação. Caracterizou-se os produtos obtidos através de análises de IV, RMN 1 1-1 e CH
Learning and Autonomy for Extraterrestrial Terrain Sampling: An Experience Report from OWLAT Deployment
Extraterrestrial autonomous lander missions increasingly demand adaptive
capabilities to handle the unpredictable and diverse nature of the terrain.
This paper discusses the deployment of a Deep Meta-Learning with Controlled
Deployment Gaps (CoDeGa) trained model for terrain scooping tasks in Ocean
Worlds Lander Autonomy Testbed (OWLAT) at NASA Jet Propulsion Laboratory. The
CoDeGa-powered scooping strategy is designed to adapt to novel terrains,
selecting scooping actions based on the available RGB-D image data and limited
experience. The paper presents our experiences with transferring the scooping
framework with CoDeGa-trained model from a low-fidelity testbed to the
high-fidelity OWLAT testbed. Additionally, it validates the method's
performance in novel, realistic environments, and shares the lessons learned
from deploying learning-based autonomy algorithms for space exploration.
Experimental results from OWLAT substantiate the efficacy of CoDeGa in rapidly
adapting to unfamiliar terrains and effectively making autonomous decisions
under considerable domain shifts, thereby endorsing its potential utility in
future extraterrestrial missions.Comment: Updated references to include recent work on autonomy for ocean
world
Influence of fertilization on nitrate content in pastures and milk in the west of Santa Catarina over the year
The indiscriminate use without criteria of nitrogen fertilization can lead to an accumulation of nitrate in pastures, animal poisoning and potential increase in residual content of this compound in milk. The objective of this study was to determine the residual levels of nitrate throughout the year in pastures and milk from small farms in western Santa Catarina (SC) that use high levels of nitrogen fertilization. The experiment was carried out from April/2018 to March/2019 on 10 dairy farms in the municipality of Riqueza (SC). Two annual collections of water samples and monthly collections of pastures and milk were carried out, in addition to obtaining information on the property and management of pasture fertilization through a structured questionnaire. Nitrate was also evaluated in pastures using the diphenylamine test. Temperature and rainfall data were obtained daily by a weather station. The average amount of nitrogen fertilizer used in the properties was 654 ± 176 kg/ha/year. The average nitrate content in the drinking water of the animals was 1.5 ± 1.4 mg/L, in the pasture it was 270 ± 76 mg/kg DM, while in milk it was 2.0 ± 0.3 mg/L. There was seasonal variation with an increase in nitrate content in pastures and milk in autumn, a period of the experiment in which low rainfall was observed. It was concluded that despite being dairy properties with high use of nitrogen fertilization, safe milk is produced in terms of nitrate levels, even in times of the year with adverse climatic conditions. The diphenylamine test has a good ability to discriminate the nitrate content in pastures and can be indicated as a quick test to verify the presence of high levels of nitrate in the pasture.O uso indiscriminado da adubação nitrogenada pode levar ao acúmulo de nitrato nas pastagens, intoxicar animais e aumentar os níveis nocivos residuais no leite destinado ao consumo humano. Dessa forma, o objetivo desse estudo foi determinar os teores de nitrato nas pastagens e no leite ao longo de um ano em propriedades que utilizam níveis elevados de adubação nitrogenada no oeste de Santa Catarina (SC). O experimento foi realizado durante o período de abril/2018 a março/2019 em dez propriedades produtoras de leite do município de Riqueza (SC). Foram realizadas duas coletas anuais de amostras de água e coletas mensais de pastagens e leite, além de obtidas informações quanto ao manejo de adubação das pastagens da propriedade. O teste de difenilamina foi realizado nas pastagens. Dados de temperatura e pluviometria foram obtidos diariamente por uma estação meteorológica. A quantidade média de adubo nitrogenado utilizado nas propriedades foi de 654 ± 176 kg/ha/ano. O teor médio de nitrato na água de consumo dos animais foi de 1,5 ± 1,4 mg/L, na pastagem foi de 270 ± 76 mg/kg MS, enquanto no leite foi de 2,0 ± 0,3mg/L. Houve variação sazonal com aumento no teor de nitrato nas pastagens e no leite no outono, período do experimento em que foi observado baixo índice pluviométrico. Concluiu-se que apesar de se tratar de propriedades leiteiras com elevada utilização de adubação nitrogenada, o leite produzido é seguro quanto aos teores de nitrato, mesmo em épocas do ano com condições climáticas adversas. O teste de difenilamina pode ser indicado como teste rápido para verificar teores elevados de nitrato na pastagem
Impacto de la reforma educativa del nivel secundario en el campo de la enseñanza de las Ciencias Económicas. 16H326
Actividades desarrolladas durante el período: Análisis y debate normativo/conceptual:compilación de documentos que abordaran el marco legislativo que avala los cambios en la educación secundaria en l actual reforma y a partir de los cuales, efectuar un análisis comparativo en búsqueda de los puntos relevantes /sustantivos de los cambios educativos que se proponen; Encuadre legal de los cambios curriculares en la Educación Secundaria; Relevamiento de la implementación: Escuelas, directivos, docentes frente a los cambios curriculares; Elaboración y formulación de entrevistas: diseño de instrumentos de recolección de datos y consulta con metodólogos; elaboración de una guía de entrevista para docentes y directivos de las diferentes instituciones escolares seleccionadas; Reflexión, análisis y producción El equipo llevó a cabo diversas reuniones para la reflexión sobre del desarrollo de la investigación y los aspectos implícitos en ella. Está en la fase de discusión de los documentos de base y del análisis de los resultados de las entrevistas a docentes y directivos de la orientación Economía y Administración. Elaboró un documento de trabajo sobre propuestas de actualizaciones curriculares del
Programa de Formación Docente en Ciencias Económicas
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Genome-wide association study of primary open-angle glaucoma in continental and admixed African populations.
Primary open angle glaucoma (POAG) is a complex disease with a major genetic contribution. Its prevalence varies greatly among ethnic groups, and is up to five times more frequent in black African populations compared to Europeans. So far, worldwide efforts to elucidate the genetic complexity of POAG in African populations has been limited. We conducted a genome-wide association study in 1113 POAG cases and 1826 controls from Tanzanian, South African and African American study samples. Apart from confirming evidence of association at TXNRD2 (rs16984299; OR[T] 1.20; P = 0.003), we found that a genetic risk score combining the effects of the 15 previously reported POAG loci was significantly associated with POAG in our samples (OR 1.56; 95% CI 1.26-1.93; P = 4.79 × 10-5). By genome-wide association testing we identified a novel candidate locus, rs141186647, harboring EXOC4 (OR[A] 0.48; P = 3.75 × 10-8), a gene transcribing a component of the exocyst complex involved in vesicle transport. The low frequency and high degree of genetic heterogeneity at this region hampered validation of this finding in predominantly West-African replication sets. Our results suggest that established genetic risk factors play a role in African POAG, however, they do not explain the higher disease load. The high heterogeneity within Africans remains a challenge to identify the genetic commonalities for POAG in this ethnicity, and demands studies of extremely large size
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Pan-viral serology implicates enteroviruses in acute flaccid myelitis.
Since 2012, the United States of America has experienced a biennial spike in pediatric acute flaccid myelitis (AFM)1-6. Epidemiologic evidence suggests non-polio enteroviruses (EVs) are a potential etiology, yet EV RNA is rarely detected in cerebrospinal fluid (CSF)2. CSF from children with AFM (n = 42) and other pediatric neurologic disease controls (n = 58) were investigated for intrathecal antiviral antibodies, using a phage display library expressing 481,966 overlapping peptides derived from all known vertebrate and arboviruses (VirScan). Metagenomic next-generation sequencing (mNGS) of AFM CSF RNA (n = 20 cases) was also performed, both unbiased sequencing and with targeted enrichment for EVs. Using VirScan, the viral family significantly enriched by the CSF of AFM cases relative to controls was Picornaviridae, with the most enriched Picornaviridae peptides belonging to the genus Enterovirus (n = 29/42 cases versus 4/58 controls). EV VP1 ELISA confirmed this finding (n = 22/26 cases versus 7/50 controls). mNGS did not detect additional EV RNA. Despite rare detection of EV RNA, pan-viral serology frequently identified high levels of CSF EV-specific antibodies in AFM compared with controls, providing further evidence for a causal role of non-polio EVs in AFM
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International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
A Quantitative Analytical Method to Test for Salt Effects on Giant Unilamellar Vesicles
Today, free-standing membranes, i.e. liposomes and vesicles, are used in a multitude of
applications, e.g. as drug delivery devices and artificial cell models. Because current
laboratory techniques do not allow handling of large sample sizes, systematic and
quantitative studies on the impact of different effectors, e.g. electrolytes, are limited.
In this work, we evaluated the Hofmeister effects of ten alkali metal halides on giant
unilamellar vesicles made of palmitoyloleoylphosphatidylcholine for a large sample size by
combining the highly parallel water-in-oil emulsion transfer vesicle preparation method with
automatic haemocytometry. We found that this new quantitative screening method is highly
reliable and consistent with previously reported results. Thus, this method may provide a
significant methodological advance in analysis of effects on free-standing model
membranes
Pattern of Relapse and Treatment Response in WNT- Activated Medulloblastoma
Over the past decade, wingless-activated (WNT) medulloblastoma has been identified as a candidate for therapy de-escalation based on excellent survival; however, a paucity of relapses has precluded additional analyses of markers of relapse. To address this gap in knowledge, an international cohort of 93 molecularly confirmed WNT MB was assembled, where 5-year progression-free survival is 0.84 (95%, 0.763-0.925) with 15 relapsed individuals identified. Maintenance chemotherapy is identified as a strong predictor of relapse, with individuals receiving high doses of cyclophosphamide or ifosphamide having only one very late molecularly confirmed relapse (p = 0.032). The anatomical location of recurrence is metastatic in 12 of 15 relapses, with 8 of 12 metastatic relapses in the lateral ventricles. Maintenance chemotherapy, specifically cumulative cyclophosphamide doses, is a significant predictor of relapse across WNT MB. Future efforts to de-escalate therapy need to carefully consider not only the radiation dose but also the chemotherapy regimen and the propensity for metastatic relapses
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