579 research outputs found
DOT-WINGED CRAKE PORZANA SPILOPTERA (RALLIDAE; DURNFORD, 1877) IN CHILE: NEW RECORDS AND A REVIEW OF THE STATUS OF PACIFIC POPULATIONS
We report new records of the Dot-winged Crake Porzana spiloptera in southern Chile, an almost unknown species distributed mainly in Argentina and recently discovered in Chile. The occasional capture of a juvenile of the species at Cruces River wetland (39°S), and the analysis of sound recordings obtained to explore the acoustic attributes of urban wetland soundscapes, made it possible to discuss the status of the Pacific populations of the species. The new records show that P. spiloptera has a resident status and suggest that the presence of the species in Chile went historically unnoticed, and that it has been confused with the Black Rail Laterallus jamaicensis. Comprehensive surveys and dedicated research that provide fundamental biological aspects such as the current distribution, population abundance, habitat requirements, and main threats for these secretive rails are urgently needed for their conservation
Regional asymmetry of metabolic and antioxidant profile in the sciaenid fish shi drum (Umbrina cirrosa) white muscle. Response to starvation and refeeding.
The objective of the present study is to characterize the metabolic and antioxidant profile of white muscle of shi drum in two sites of the body, anterior dorsal (AM) and posterior dorsal (PM) portions. In addition, it will be analyzed the possible effect of starvation and a subsequent refeeding, with two different protocols, pair feeding and ad libitum. Activities of key enzymes of intermediary metabolism and of antioxidant enzymes, as well as lipid peroxidation, as an index of oxidative stress, were evaluated. The results indicate the existence of a regional asymmetry of the metabolic capacities of the white muscle of shi drum, which is likely related to the different contribution to swimming of the body regions examined. Starvation induces a metabolic depression that is more marked in those activities that support burst swimming in PM, while those activities supporting maintenance requirements are conserved. The greatest energy demands during starvation appear to lie in AM, which showed the highest oxidative metabolism rate. The increased use of fatty acids as energy source for AM leads to oxidative stress. A period of more than four weeks of refeeding for full restoration of metabolic capacities in AM is needed, probably related to the higher muscle mass located in this region. On the contrary, all enzyme activities in PM returned to control levels in both refeeding protocols, but pair feeding seems to be advantageous
since compensatory growth has been taking place without signs of oxidative stress. This work was addressed to gain knowledge on the physiology of a promising fish species in aquaculture like shi drum. The results displayed here show how the starving and further re-feeding events could generate oxidative stress situations characterized by high lipid peroxidation levels which may influence negatively on the quality of the edible part of the fish. This study opens an interesting field on this fish species which deserves being investigated in the future.Versión del edito
Time Course of Metabolic Capacities in Paralarvae of the Common Octopus, Octopus vulgaris, in the First Stages of Life. Searching Biomarkers of Nutritional Imbalance
The culture of the common octopus (Octopus vulgaris) is promising since the species has a relatively short lifecycle, rapid growth, and high food conversion ratios. However, recent attempts at successful paralarvae culture have failed due to slow growth and high mortality rates. Establishing an optimal nutritional regime for the paralarvae seems to be the impeding step in successful culture methods. Gaining a thorough knowledge of food regulation and assimilation is essential for paralarvae survival and longevity under culture conditions. The aim of this study, then, was to elucidate the characteristic metabolic organization of octopus paralarvae throughout an ontogenic period of 12 days post-hatching, as well as assess the effect of diet enrichment with live prey containing abundant marine phospholipids. Our results showed that throughout the ontogenic period studied, an increase in anaerobic metabolism took place largely due to an increased dependence of paralarvae on exogenous food. Our studies showed that this activity was supported by octopine dehydrogenase activity, with a less significant contribution of lactate dehydrogenase activity. Regarding aerobic metabolism, the use of amino acids was maintained for the duration of the experiment. Our studies also showed a significant increase in the rate of oxidation of fatty acids from 6 days after-hatching. A low, although sustained, capacity for de novo synthesis of glucose from amino acids and glycerol was also observed. Regardless of the composition of the food, glycerol kinase activity significantly increased a few days prior to a massive mortality event. This could be related to a metabolic imbalance in the redox state responsible for the high mortality. Thus, glycerol kinase might be used as an effective nutritional and welfare biomarker. The studies in this report also revealed the important finding that feeding larvae with phospholipid-enriched Artemia improved animal viability and welfare, significantly increasing the rate of survival and growth of paralarvae.En prens
Long-Term Weight Loss Success and the Health Behaviors of Adults in the United States:Findings from a Nationally Representative Cross-sectional Study
Objective To describe the relationship between long-term weight loss (LTWL) success and lifestyle behaviours among US adults.Design Serial cross-sectional data from National Health and Nutrition Examination Survey cycles 2007–2014.Setting and participants Population-based nationally representative sample. The analytic sample included 3040 adults aged 20–64 years who tried to lose weight in the past year.Measures Participants were grouped into five LTWL categories (<5%, 5%–9.9%, 10%–14.9%, 15%–19.9% and ≥20%). Lifestyle-related behaviours included the following: alcohol intake, physical activity, smoking, fast-food consumption, dietary quality (Healthy Eating Index (HEI)) and caloric intake. Multivariable regression was employed adjusting for age, sex, race/ethnicity, marital status, education, household income and size, current body mass index and self-reported health status.Results Individuals in the 15%–19.9% LTWL group differed significantly from the reference group (<5% LTWL) in their physical activity and dietary quality (HEI) but not caloric intake. Specifically, they had a higher HEI score (β=3.19; 95% CI 0.39 to 5.99) and were more likely to meet physical activity guidelines (OR=1.99; 95% CI 1.11 to 3.55). In comparison, the ≥20% LTWL group was significantly more likely to smoke (OR=1.63; 95% CI 1.03 to 2.57) and to consume lower daily calories (β=−202.91; 95% CI –345.57 to –60.25) than the reference group; however, dietary quality and physical activity did not significantly differ.Conclusion Among a national sample of adults, a higher level of LTWL success does not necessarily equate to healthy weight loss behaviours. Future research should attempt to design interventions aimed at facilitating weight loss success while encouraging healthy lifestyle behaviours
Antioxidant activity, photosynthetic rate, and Spectral mass in bean Plants (Phaseolus vulgaris L.) in Response to Stress Defense Activators
An increase in antioxidant activity is a common response in plants as a defense mechanism against biotic and abiotic stress factors, such response is also generated with the exogenous application of "defense activators", which have negative effects on plant metabolism. In this work, bean plants (Phaseolus vulgaris L.) cv. Pinto Nacional were treated with jasmonic acid (0.5 mM), salicylic acid (2 mM), Trichoderma asperellum (105 spores/ml), and Bacillus pumilus (105 CFU / mL), in order to determine the level of structural and metabolic response of the plants. On the seventh day after the application of the treatments, it was measured the enzymatic activity of catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD). In addition, leaf impressions were taken to measure the stomatal opening and conductance, photosynthetic rate, and the mass spectrum (mass/charge, m/z). The antioxidant activity increased in plants treated with jasmonic acid and T. asperellum, which in turn significantly increased the stomatal opening and conductance, and photosynthetic rate. The mass profile showed that the plants treated with T. asperellum have a greater quantity of masses/charge, of which some had statistically highly significant difference according to the means test Tukey (
Design for FDM of flexible tooling for manufacturing aeronautical components by incremental sheet forming
IOP Conf. Series: Materials Science and Engineering 1193Nowadays, industrial production is required to reduce industrialization times and
development costs for new products while maintaining high quality standards. In this context,
the development of new flexible manufacturing technologies has gained relevance in the last few
years. The use of Fused Deposition Modelling (FDM) additive technique has been recently
proposed in different industrial sectors for manufacturing rapid tooling (dies) to be used in
conventional sheet metal stamping or stretching processes with a significant decrease in costs
and time savings. On the other hand, Incremental Sheet Forming (ISF) technology is
characterized by an enhanced formability of the parts thus manufactured as well as for the need
of a small number of tooling, reducing costs compared to conventional processes such as
hydroforming or stamping. In particular, its simplest variant, Single-Point Incremental Forming
(SPIF) requires the use of backing plates, which do not require tight tolerances as their only
function is to collaborate in the deformation process acting as a support point. Furthermore, the
strength requirements are also not a limitation since the forces involved in SPIF are very small
given the local nature of the deformation. In this context, the main objective of this work is the
design of a modular tooling system, manufactured using the FDM additive technique, that allows
the flexible manufacturing of different aeronautical components by SPIF.Universidad de Sevilla US-1263138Ministerio de Ciencia e Innovación (MICIN). España PGC2018-095508-B-I00Junta de Andalucía P18-RT-386
Organochlorine exposure and colorectal cancer risk
Organochlorine compounds have been linked to increased risk of several cancers. Despite reductions in their use and fugitive release, they remain one of the most important groups of persistent pollutants to which humans are exposed, primarily through dietary intake. We designed a case-control study to assess the risk of colorectal cancer with exposure to these chemicals, and their potential interactions with genetic alterations in the tumors. A subsample of cases (n = 132) and hospital controls (n = 76) was selected from a larger case-control study in Barcelona, Catalonia, Spain. We measured concentrations in serum of several organochlorines by gas chromatography. We assessed point mutations in K-ras and p53 genes in tissue samples by polymerase chain reaction/single-strand conformation polymorphism and assessed expression of p53 protein by immunohistochemical methods. An elevated risk of colorectal cancer was associated with higher serum concentrations of mono-ortho polychlorinated biphenyl (PCB) congeners 28 and 118. The odds ratio for these mono-ortho PCBs for middle and higher tertile were, respectively, 1.82 [95% confidence interval (CI), 0.90-3.70] and 2.94 (95% CI, 1.39-6.20). alpha-Hexachlorocyclohexane, hexachlorobenzene, and pp'-DDE (4,4'-dichlorodiphenyltrichloroethene) showed nonsignificant increases in risk. Risk associated with mono-ortho PCBs was slightly higher for tumors with mutations in the p53 gene but was not modified by mutations in K-ras. Mono-ortho PCBs were further associated with transversion-type mutations in both genes. These results generate the hypothesis that exposure to mono-ortho PCBs contributes to human colorectal cancer development. The trend and magnitude of the association, as well as the observation of a molecular fingerprint in tumors, raise the possibility that this finding may be causal
Remediación de suelos contaminados con hidrocarburos empleando sustancias húmicas de vermicomposta
La biorremediación utilizando sustancias húmicas es una de las técnicas recientes y prometedoras para la restauración de suelos contaminados por hidrocarburos, pero existe poca información sobre su comportamiento en los diversos tipos de suelo. Por estas razones, esta investigación tuvo como objetivo evaluar la remoción de hidrocarburos totales del petróleo o HTP en tres suelos con diferentes texturas (S1, S2 y S3) y tratados con enmiendas orgánicas de vermicomposta (cascarillas de cacao, Theobroma cacao; arroz, Oriza sativa; bagazo de caña, Saccharum officinarum; estiércol de vaca) y sustancias húmicas comerciales (humato de potasio). Se planteó un diseño experimental multifactorial aleatorio (3 × 3 × 2), constituido por tipo de suelo, enmienda orgánica (sin vermicomposta, con vermicomposta orgánica, con sustancias húmicas comerciales), y carga microbiana (con microorganismos, sin microorganismos). Los resultados fueron analizados mediante las pruebas ANOVA-Tukey en el programa Statgraphics Centurion TM V.18 (α = 0.05) con el fin de evaluar diferencias significativas entre los tratamientos. Los resultados muestran que S2 con vermicomposta orgánica tuvo la mayor remoción (86% de HTP) luego de 60 días de incubación, en comparación con el tratamiento con sustancias húmicas comerciales, relacionándose con la baja biodisponibilidad de microorganismos. Este comportamiento también se observó en S3, el cual tuvo un porcentaje de remoción de HTP de 77.52 y 63.4%. Finalmente, la tasa de crecimiento celular fue mejor en S2 con sustancias húmicas comerciales. Se obtuvo un crecimiento promedio de 94×104 UFC g-1 de suelo durante los 60 días de evaluación del experimento, y un máximo de 98×105 UFC g-1 de suelo a los 45 días de tratamiento. Se concluye que el uso de vermicomposta es adecuada para suelos arcillosos, ya que las tasas de degradación son mayores en ellos. Además, representan una alternativa de menor costo que los tratamientos sintéticos y de revalorización de residuos orgánicos
Asociaciones entre atención conjunta y estimulación en el hogar en contexto de COVID-19
The objective of this research was to describe the type of stimulation at home and the joint attention of infants during the context of the COVID-19 pandemic, as well as to evaluate the possible association between these variables. The sample consisted of 55 primary caregivers of Argentine infants aged 9 months to 3 years (M = 1.63, SD = 0.8, male n = 24). An ad hoc sociodemographic questionnaire, an ad hoc Home Stimulation Questionnaire and the Joint Attention Scale of Wetherby and Prizant (2002) were administered, for which all variables were collected by self-report. It was found that the TV was the device most used by infants, and that TV, cell phone, and Internet use were actively shared with caregivers. In turn, the levels of joint attention behaviors were high for this sample. A positive association was also found between shared reading, joint attention and contact with relatives. On the contrary, the more reading, the less daily TV use by the child. In turn, it was found that high number of months out of work, were associated to high levels of joint attention, and the only factor that positively predicted joint attention was unemployment. Finally, it was found that a greater number of books in the home was positively associated with recreational activities with the child and negatively associated with cell phone use. In this sense, a higher level of cell phone use by the child was associated with a greater consumption of news associated with COVID-19 by the caregiver. It is concluded that it is necessary to work on the amount of time that infants are exposed to technological devices and promote joint attention spaces, such as shared reading in the early years of development.La presente investigación tuvo como objetivo describir el tipo de estimulación en el hogar y la atención conjunta de infantes durante el contexto de pandemia por COVID-19, así como también evaluar la posible asociación entre dichas variables. La muestra estuvo conformada por 55 cuidadores primarios/as de infantes argentinos de 9 meses a 3 años (M = 1 .63, DE = 0.8, masculino n = 24). Se administró un cuestionario sociodemográfico ad hoc, un Cuestionario de Estimulación en el Hogar ad hoc y la Escala de Atención Conjunta de Wetherby y Prizant (2002), por lo que todas las variables fueron recolectadas mediante autorreporte. Se encontró que la TV fue el dispositivo más utilizado por los infantes, y que la TV, el celular y el uso de Internet eran compartidos de forma activa con los cuidadores. A su vez, los niveles de conductas de atención conjunta fueron elevados para esta muestra. También se encontró una asociación positiva entre la lectura compartida, la atención conjunta y el contacto con familiares. Por el contrario, a mayor lectura menor uso diario de TV por parte del niño/a. A su vez, cuanto mayor era la cantidad de meses sin trabajo, más aumentaba la atención conjunta, y el único factor que predijo positivamente la atención compartida fue el desempleo. Por último, se halló que una mayor cantidad de libros en el hogar se asoció positivamente con las salidas recreativas con el niño/a y negativamente con el uso del celular. En este sentido, cuanto mayor fue el uso del celular por parte del niño/a hubo un mayor consumo de noticias asociadas al COVID-19 por parte del cuidador. Se concluye que se debe trabajar en la cantidad de tiempo que los infantes están expuestos a dispositivos tecnológicos y promover espacios de atención conjunta, tales como la lectura compartida en los primeros años del desarrollo
Genomic diversity of burkholderia pseudomalleiIsolates, Colombia
We report an analysis of the genomic diversity of isolates of Burkholderia pseudomallei, the cause of melioidosis, recovered in Colombia from routine surveillance during 2016–2017. B. pseudomallei appears genetically diverse, suggesting it is well established and has spread across the region
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