82 research outputs found

    Comments on Marine Litter in Oceans, Seas and Beaches: Characteristics and Impacts.

    Get PDF
    Marine litter is observed along shorelines, pelagic, benthic marine and lake systems all around the globe. On beaches, litter creates aesthetic and related economic problems because a clean beach is one of the most important characteristics of a seaside resort required by visitors. Litter can reach the marine environment from marine or land activities but it is estimated that 80% originates from land-based sources. The marine-based sources of litter include all types of sea-going vessel and offshore installations, the most abundant plastic debris in the oceans being derelict (lost or improperly discarded) fishing gear. Most of marine litter is composed by plastics due to their greater durability and persistence, combined with plastic rising production and low rates of recovery. Special importance is linked to microplastics because their ubiquity, persistence, mechanical effects on biota and the ecosystem because of ingestion by organisms and their toxic potential. As plastics degrade they can release toxic chemicals initially incorporated during their manufacturing or persistent organic pollutants and heavy metals sorbed to their surfaces in the environment. Such toxins can disrupt endocrine functions and cause harmful reproductive and developmental effects in aquatic animals

    Galletas con grasas cero trans a base de soja formuladas usando una red neuronal artificial.

    Get PDF
    This study applied Artificial Neural Network (ANN) technology to formulate zero trans fat blends derived from soybeans and to evaluate their performance when applied to the processing of sweet laminated biscuits. For the formulation of the blends, two interesterified soybean fats and soybean oil were used as bases. They were characterized in terms of melting point, solid fat content and fatty acid composition; and the biscuits produced were analyzed for their technological (dimensions, mass, volume, expansion, instrumental color and texture, moisture gradient and cracking) and physicochemical characteristics (total fat and moisture contents, water activity and fatty acid composition). It was possible to verify the use of ANN to develop zero trans fats derived from soybeans for application in sweet laminated biscuits, which represents an operational and financial advantage. Moreover, we showed the viability of using soybean fats/oil, raw materials of greater availability and lower cost, for the production of biscuits.Este estudio aplic? la tecnolog?a de Redes Neuronales Artificiales (RNA) para formular mezclas de grasas cero trans derivadas de soja y evaluar su papel cuando se usan en el procesamiento de galletas dulces laminadas. Para la formulaci?n de las mezclas se usaron como base dos grasas de soja interesterificadas as? como aceite de soja. Se caracterizaron en t?rminos de punto de fusi?n, contenido de grasa s?lida y composici?n de ?cidos grasos, y a las galletas se les determin? sus caracter?sticas tecnol?gicas (dimensiones, masa, volumen, color, textura, gradiente de humedad as? como otros controles) y fisicoqu?micas (contenidos de grasa total, humedad, actividad de agua y composici?n de ?cidos grasos). Fue posible verificar el uso de RNA para desarrollar grasas cero trans derivadas de soja, para su aplicaci?n en galletas dulces laminadas, lo que representa una ventaja operativa y financiera. Adem?s, mostramos la viabilidad de usar grasas/aceite de soja, materias primas de mayor disponibilidad y menor costo, para la producci?n de galletas

    Citizenship status and career self-efficacy: An intersectional study of biomedical trainees in the United States

    Get PDF
    This study examines the intersectional role of citizenship and gender with career self-efficacy amongst 10,803 doctoral and postdoctoral trainees in US universities. These biomedical trainees completed surveys administered by 17 US institutions that participated in the National Institutes of Health Broadening Experiences in Scientific Training (NIH BEST) Programs. Findings indicate that career self-efficacy of non-citizen trainees is significantly lower than that of US citizen trainees. While lower career efficacy was observed in women compared with men, it was even lower for non-citizen female trainees. Results suggest that specific career interests may be related to career self-efficacy. Relative to US citizen trainees, both male and female non-citizen trainees showed higher interest in pursuing a career as an academic research investigator. In comparison with non-citizen female trainees and citizen trainees of all genders, non-citizen male trainees expressed the highest interest in research-intensive (and especially principal investigator) careers. The authors discuss potential causes for these results and offer recommendations for increasing trainee career self-efficacy which can be incorporated into graduate and postdoctoral training

    Career self-efficacy disparities in underrepresented biomedical scientist trainees

    Get PDF
    The present study examines racial, ethnic, and gender disparities in career self-efficacy amongst 6077 US citizens and US naturalized graduate and postdoctoral trainees. Respondents from biomedical fields completed surveys administered by the National Institutes of Health Broadening Experiences in Scientific Training (NIH BEST) programs across 17 US institutional sites. Graduate and postdoctoral demographic and survey response data were examined to evaluate the impact of intersectional identities on trainee career self-efficacy. The study hypothesized that race, ethnicity and gender, and the relations between these identities, would impact trainee career self-efficacy. The analysis demonstrated that racial and ethnic group, gender, specific career interests (academic principal investigator vs. other careers), and seniority (junior vs. senior trainee level) were, to various degrees, all associated with trainee career self-efficacy and the effects were consistent across graduate and postdoctoral respondents. Implications for differing levels of self-efficacy are discussed, including factors and events during training that may contribute to (or undermine) career self-efficacy. The importance of mentorship for building research and career self-efficacy of trainees is discussed, especially with respect to those identifying as women and belonging to racial/ethnic populations underrepresented in biomedical sciences. The results underscore the need for change in the biomedical academic research community in order to retain a diverse biomedical workforce

    Method for obtaining high-resolution proteomic analysis from pericarps of guarana

    Get PDF
    Guarana has great agricultural potential and is largely used therapeutically and in the production of non-alcoholic energy drinks. Genomic and proteomic studies are crucial to identify proteins that play central roles in the maintenance and viability of fruits, as well as to identify proteins related to the main metabolic pathways. However, the success of any protein analysis starts with the protein extract preparation, which needs to offer an extract that is free of contaminants. This study aimed to evaluate different extraction methods to obtain high-quantity and high-quality extracts that are compatible with analysis by 2-dimensional electrophoresis and tandem mass spectrometry protein identification. Three different methods were tested: trichloroacetic acid (TCA)/acetone, sodium dodecyl sulfate (SDS)/phenol, and polyvinylpolypyrrolidone (PVPP)/SDS/phenol. The extract obtained from the TCA/acetone precipitation presented low solubility and contamination with lipids and carbohydrates. On the other hand, the quality of the extract gradually improved after using phenol and PVPP/phenol, enabling a yield up to 2 mg/g macerated tissues and the detection of 457 spots by 2-dimensional electrophoresis. The effectiveness of the procedure used was validated by identification of 10 randomly selected proteins by mass spectrometry. The procedure described here can be a starting point for applications using tissues of other organs of guarana or tissues of species that are similar to guarana. © FUNPEC-RP

    Electrophoresis and spectrometric analyses of adaptation-related proteins in thermally stressed Chromobacterium violaceum

    Get PDF
    Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry. The total number of spots detected was 1985; the number ranged from 99 to 380 in each assay. The proteins that were identified spectrometrically were categorized as chaperones, proteins expressed exclusively under heat stress, enzymes involved in the respiratory and fermentation cycles, ribosomal proteins, and proteins related to transport and secretion. Controlling inverted repeat of chaperone expression and inverted repeat DNA binding sequences, as well as regions recognized by sigma factor 32, elements involved in the genetic regulation of the bacterial stress response, were identified in the promoter regions of several of the genes coding proteins, involved in the C. violaceum stress response. We found that 30°C is the optimal growth temperature for C. violaceum, whereas 25, 35, and 40°C are stressful temperatures that trigger the expression of chaperones, superoxide dismutase, a probable small heat shock protein, a probable phasing, ferrichrome-iron receptor protein, elongation factor P, and an ornithine carbamoyltransferase catabolite. This information improves our comprehension of the mechanisms involved in stress adaptation by C. violaceum. © FUNPEC-RP
    • …
    corecore