182 research outputs found
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Radiogenic backgrounds in the NEXT double beta decay experiment
Natural radioactivity represents one of the main backgrounds in the search for neutrinoless double beta decay. Within the NEXT physics program, the radioactivity- induced backgrounds are measured with the NEXT-White detector. Data from 37.9 days of low-background operations at the Laboratorio Subterráneo de Canfranc with xenon depleted in 136Xe are analyzed to derive a total background rate of (0.84±0.02) mHz above 1000 keV. The comparison of data samples with and without the use of the radon abatement system demonstrates that the contribution of airborne-Rn is negligible. A radiogenic background model is built upon the extensive radiopurity screening campaign conducted by the NEXT collaboration. A spectral fit to this model yields the specific contributions of 60Co, 40K, 214Bi and 208Tl to the total background rate, as well as their location in the detector volumes. The results are used to evaluate the impact of the radiogenic backgrounds in the double beta decay analyses, after the application of topological cuts that reduce the total rate to (0.25±0.01) mHz. Based on the best-fit background model, the NEXT-White median sensitivity to the two-neutrino double beta decay is found to be 3.5σ after 1 year of data taking. The background measurement in a Qββ±100 keV energy window validates the best-fit background model also for the neutrinoless double beta decay search with NEXT-100. Only one event is found, while the model expectation is (0.75±0.12) events. [Figure not available: see fulltext.]
Voltage-gated sodium channels as targets for pyrethroid insecticides
The pyrethroid insecticides are a very successful group of compounds that have been used extensively for the control of arthropod pests of agricultural crops and vectors of animal and human disease. Unfortunately, this has led to the development of resistance to the compounds in many species. The mode of action of pyrethroids is known to be via interactions with the voltage-gated sodium channel. Understanding how binding to the channel is affected by amino acid substitutions that give rise to resistance has helped to elucidate the mode of action of the compounds and the molecular basis of their selectivity for insects vs mammals and between insects and other arthropods. Modelling of the channel/pyrethroid interactions, coupled with the ability to express mutant channels in oocytes and study function, has led to knowledge of both how the channels function and potentially how to design novel insecticides with greater species selectivity
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Demonstration of the event identification capabilities of the NEXT-White detector
In experiments searching for neutrinoless double-beta decay, the possibility of identifying the two emitted electrons is a powerful tool in rejecting background events and therefore improving the overall sensitivity of the experiment. In this paper we present the first measurement of the efficiency of a cut based on the different event signatures of double and single electron tracks, using the data of the NEXT-White detector, the first detector of the NEXT experiment operating underground. Using a 228Th calibration source to produce signal-like and background-like events with energies near 1.6 MeV, a signal efficiency of 71.6 ± 1.5 stat± 0.3 sys% for a background acceptance of 20.6 ± 0.4 stat± 0.3 sys% is found, in good agreement with Monte Carlo simulations. An extrapolation to the energy region of the neutrinoless double beta decay by means of Monte Carlo simulations is also carried out, and the results obtained show an improvement in background rejection over those obtained at lower energies. [Figure not available: see fulltext.
The short-term effect of whole body vibration training on physical capabilities on active young recreational athletes
In recent years, whole body vibration (WBV) has been the subject of a great amount of research towards improving physical capabilities as a postactivation potentiation because the muscle spindle’s sensitivity can be increased (Rittweger, 2010). Typically, WBV is realized by the subject above the platform in squat position while the platform oscillates at differences intensities and amplitudes. Previous reports have shown that WBV produces preconditioning effects that lead an increase of power and flexibility (Jacobs & Burns, 2009), but controversial data exists that have shown no positive effect if an optimal dosage is not used in a controlled manner (Wilcock et al., 2009) and it has been suggested that the frequency may affect output (Turner et al., 2011). The purpose of this study was to investigate the effects of a single bout of whole-body vibration at two different frequencies on isometric lumbar extension (ELE), isometric deadlift (ID), posterior leg flexibility (PLF) and core muscle endurance test (CMET)
Shared midgut binding sites for Cry1A.105, Cry1Aa, Cry1Ab, Cry1Ac and Cry1Fa proteins from Bacillus thuringiensis in two important corn pests, Ostrinia nubilalis and Spodoptera frugiperda
First generation of insect-protected transgenic corn (Bt-corn) was based on the expression of Cry1Ab or Cry1Fa proteins. Currently, the trend is the combination of two or more genes expressing proteins that bind to different targets. In addition to broadening the spectrum of action, this strategy helps to delay the evolution of resistance in exposed insect populations. One of such examples is the combination of Cry1A.105 with Cry1Fa and Cry2Ab to control O. nubilalis and S. frugiperda. Cry1A.105 is a chimeric protein with domains I and II and the C-terminal half of the protein from Cry1Ac, and domain III almost identical to Cry1Fa. The aim of the present study was to determine whether the chimeric Cry1A.105 has shared binding sites either with Cry1A proteins, with Cry1Fa, or with both, in O. nubilalis and in S. frugiperda. Brush-border membrane vesicles (BBMV) from last instar larval midguts were used in competition binding assays with 125I-labeled Cry1A.105, Cry1Ab, and Cry1Fa, and unlabeled Cry1A.105, Cry1Aa, Cry1Ab, Cry1Ac, Cry1Fa, Cry2Ab and Cry2Ae. The results showed that Cry1A.105, Cry1Ab, Cry1Ac and Cry1Fa competed with high affinity for the same binding sites in both insect species. However, Cry2Ab and Cry2Ae did not compete for the binding sites of Cry1 proteins. Therefore, according to our results, the development of cross-resistance among Cry1Ab/Ac, Cry1A.105, and Cry1Fa proteins is possible in these two insect species if the alteration of shared binding sites occurs. Conversely, cross-resistance between these proteins and Cry2A proteins is very unlikely in such case
Referentes teóricos de la atención a los educandos del nivel educativo primaria con comportamientos inadecuados
In the work a scientific result is presented obtained in the student scientific work, executed from the labor-investigative practice in the primary school “Sergio Luis Ramos” of the municipality Manzanillo, directed to the solution of the problem related with the execution of the school duties of the scholar of fifth grade of the primary educational level in Mathematics's class. The objective is to present the data obtained in the determination of the mark theoretical referential, contextual theoretical mark and the state of the art from the advice to the teachers directed to its preparation to assist the behavior of the scholar in the school context and to achieve the learning in the Mathematical subject. Assisting to the objective and the nature of the variables study object, a study was developed with qualitative investigation focus, following the narrative of the paradigm of hermeneutic investigation; from an observational design of type: exploratory and descriptive, using methods and technical of the theoretical level: documental, analytic-synthetic and inductive-deductive analysis. The results of this theoretical study allowed to determine the solutions that he/she has received the problem, the aspects that have not been solved satisfactorily and, therefore, to evidence the necessity to introduce new proposals that they allow their improvement to achieve the execution of the school duties of the scholars and the learning in the Mathematical subject.En el trabajo se presenta un resultado científico obtenido en el trabajo científico estudiantil, ejecutado desde la práctica laboral-investigativa en la escuela primaria “Sergio Luis Ramos” del municipio Manzanillo, dirigido a la solución de la problemática relacionada con el cumplimiento de los deberes escolares de los educandos de quinto grado del nivel educativo primaria en la clase de Matemática. El objetivo es presentar los datos obtenidos en la determinación del marco teórico referencial, marco teórico contextual y el estado del arte de la asesoría psicopedagógica a los maestros dirigida a su preparación para atender el comportamiento de los educandos en el contexto escolar y lograr el aprendizaje en la asignatura Matemática. Atendiendo al objetivo y a la naturaleza de las variables objeto de estudio, se desarrolló un estudio con enfoque de investigación cualitativo, siguiendo la narrativa del paradigma de investigación hermenéutico; desde un diseño observacional de tipo: exploratoria y descriptiva, utilizando métodos y técnicas del nivel teórico: análisis documental, analítico-sintético e inductivo-deductivo. Los resultados de este estudio teórico permitieron determinar las soluciones que ha recibido la problemática, los aspectos que no han sido solucionados satisfactoriamente y, por tanto, evidenciar la necesidad de introducir nuevas propuestas que permitan su perfeccionamiento para lograr el cumplimiento de los deberes escolares de los educandos y el aprendizaje en la asignatura Matemática
Sexual Relationships in Hispanic Countries: a Literature Review
This is a pre-print of an article published in Current Sexual Health Reports. The final authenticated version is available online at: https://doi.org/10.1007/s11930-020-00272-6Purpose of Review:
Sexuality is a complex dimension for which culture seems to play an important role, particularly in countries that are more traditional. This review summarizes the knowledge about sexual relationships in Hispanic countries, considering sexual debut, attitudes, behaviors, and satisfaction.
Recent Findings:
In line with the literature reviewed, the sexual double standard seems to be continuing to influence sexual relationships. Some countries show more open expressions of sexuality based on the level of gender inequality or sexualized context, and within countries, variables such as religious commitment, family characteristics, and access to resources may play important roles in sexuality.
Summary:
Future research, policies, and interventions should consider these specific characteristics, including these forms of expression of sexuality, in the adjustment of cross-cultural and cross-national strategies
Health effects of identifying patients with undiagnosed obstructive sleep apnea in the preoperative clinic: a follow-up study
Construction and evaluation of a whole genome microarray of Chlamydomonas reinhardtii
Toepel J, Albaum S, Arvidsson S, et al. Construction and evaluation of a whole genome microarray of Chlamydomonas reinhardtii. BMC Genomics. 2011;12(1): 579.ABSTRACT: BACKGROUND: Chlamydomonas reinhardtii is widely accepted as a model organism regarding photosynthesis, circadian rhythm, cell mobility, phototaxis, and biotechnology. The complete annotation of the genome allows transcriptomic studies, however a new microarray platform was needed. Based on the completed annotation of Chlamydomonas reinhardtii a new microarray on an Agilent platform was designed using an extended JGI 3.1 genome data set which included 15000 transcript models. RESULTS: In total 44000 probes were determined (3 independent probes per transcript model) covering 93% of the transcriptome. Alignment studies with the recently published AUGUSTUS 10.2 annotation confirmed 11000 transcript models resulting in a very good coverage of 70% of the transcriptome (17000). Following the estimation of 10000 predicted genes in Chlamydomonas reinhardtii our new microarray, nevertheless, covers the expected genome by 90-95%. CONCLUSIONS: To demonstrate the capabilities of the new microarray, we analyzed transcript levels for cultures grown under nitrogen as well as sulfate limitation, and compared the results with recently published microarray and RNA-seq data. We could thereby confirm previous results derived from data on nutrient-starvation induced gene expression of a group of genes related to protein transport and adaptation of the metabolism as well as genes related to efficient light harvesting, light energy distribution and photosynthetic electron transport
The Relationship between Regular Sports Participation and Vigilance in Male and Female Adolescents
The present study investigated the relationship between regular sport participation (soccer) and vigilance performance. Two groups of male and female adolescents differentiated in terms of their sport participation (athletes, n = 39, and non-athletes, n = 36) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In the other session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance. Perceived arousal prior to the task and motivation toward the task were also measured in the PVT session. The results revealed that athletes had better cardiovascular fitness and showed better performance in the PVT. However, correlation analyses did not show any significant relationship between cardiovascular fitness and performance in the PVT. Athletes showed larger scores in motivation and perceived arousal measures with respect to non-athletes, although, once again, these variables were not correlated with PVT performance. Gender differences were observed only in the Leger test, with males showing greater fitness level than females. The major outcome of this research points to a positive relationship between regular sport participation and vigilance during adolescence. This relationship did not seem to be influenced by gender, perceived arousal, motivation toward the task or cardiovascular fitness. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between physical activity and cognitive functioning.This research was supported by a Spanish
Ministerio de Educación y Cultura (https://sede. educacion.gob.es) predoctoral grant (FPU13-05605) to the first author, and project research grants: Junta de Andalucia Proyecto de Excelencia SEJ-6414
(http://www.juntadeandalucia.es) and Ministerio de Economía y Competitividad PSI2013-46385 (http://www.mineco.gob.es) to DS and FH
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