591 research outputs found
Editorial: Interactions Between Education, Practice of Physical Activity and Psychological Well-Being
During the elaboration of this Research Topic, our dear
colleague Valerii Malkin from the Federal University of the
Urals (Russia) passed away. We hope that this work constitutes
some kind of homage to his person and academic figure, very
relevant in the complex effort to make visible the Russian
Psychology of Sport, of such a long and fruitful tradition
in past years. AM-M was a recipient of a José Castillejo
Fellowship from the Spanish Ministry of Science, Innovation, and
Universities (CAS19/00265)
Dynamics of Wolbachia pipientis gene expression across the Drosophila melanogaster life cycle
Symbiotic interactions between microbes and their multicellular hosts have
manifold impacts on molecular, cellular and organismal biology. To identify
candidate bacterial genes involved in maintaining endosymbiotic associations
with insect hosts, we analyzed genome-wide patterns of gene expression in the
alpha-proteobacteria Wolbachia pipientis across the life cycle of Drosophila
melanogaster using public data from the modENCODE project that was generated in
a Wolbachia-infected version of the ISO1 reference strain. We find that the
majority of Wolbachia genes are expressed at detectable levels in D.
melanogaster across the entire life cycle, but that only 7.8% of 1195 Wolbachia
genes exhibit robust stage- or sex-specific expression differences when studied
in the "holo-organism" context. Wolbachia genes that are differentially
expressed during development are typically up-regulated after D. melanogaster
embryogenesis, and include many bacterial membrane, secretion system and
ankyrin-repeat containing proteins. Sex-biased genes are often organised as
small operons of uncharacterised genes and are mainly up-regulated in adult
males D. melanogaster in an age-dependent manner suggesting a potential role in
cytoplasmic incompatibility. Our results indicate that large changes in
Wolbachia gene expression across the Drosophila life-cycle are relatively rare
when assayed across all host tissues, but that candidate genes to understand
host-microbe interaction in facultative endosymbionts can be successfully
identified using holo-organism expression profiling. Our work also shows that
mining public gene expression data in D. melanogaster provides a rich set of
resources to probe the functional basis of the Wolbachia-Drosophila symbiosis
and annotate the transcriptional outputs of the Wolbachia genome.Comment: 58 pages, 6 figures, 6 supplemental figures, 4 supplemental files
(available at
https://github.com/bergmanlab/wolbachia/tree/master/gutzwiller_et_al/arxiv
Effective mass enhancement in two-dimensional electron systems: the role of interaction and disorder effects
Recent experiments on two-dimensional (2D) electron systems have found a
sharp increase in the effective mass of electrons with decreasing electron
density. In an effort to understand this behavior we employ the many-body
theory to calculate the quasiparticle effective mass in 2D electron systems.
Because the low density regime is explored in the experiments we use the
approximation where the vertex correction describes the
correlation effects to calculate the self-energy from which the effective mass
is obtained. We find that the quasiparticle effective mass shows a sharp
increase with decreasing electron density. Disorder effects due to charged
impurity scattering plays a crucial role in density dependence of effective
mass.Comment: To appear in Solid State Communication
Light Therapy Device for Entrainment of Circadian Rhythm Desynchronization in Microgravity
The circadian rhythm is an internal process of the brain that regulates the sleep-wake cycle. Outside environmental factors can affect the circadian rhythm such as light and dark. In microgravity, astronauts witness the sun rise and set approximately 16 times per day. A disruption (desynchronization) of the circadian rhythm may then occur, with some astronauts reporting to be less alert and unable to sufficiently complete tasks. PURPOSE: To design, fabricate, and test a pair of glasses that emit blue wavelengths of light peripheral to the eyes, for set periods of time, which may promote alertness in astronauts. METHODS: The custom fitted glasses were originally designed in three-dimensional modeling software (Solidworks Premium, Waltham, MA). Components of the glasses included: frames, an Arduino Nano circuit board, tactile button switch, inductive charging components and battery, a wireless charging transmitter, and blue LEDs. The glasses emit 1000 lux at approximately 468 nm wavelength of blue light. The glasses were programmed using C++ to allow the user to wear the glasses for 30 minutes with an automatic timer to turn off the lights upon completion of the session. When fully charged, the battery can sustain a total of 8 sessions with each lasting 30 minutes. To further assess the functionality of the glasses, brainwaves measured via electroencephalography (EEG) and reaction time measured via the psychomotor vigilance test (PVT) were collected before, immediately after, and one hour after a 30-min trial session while wearing the glasses in the “on” position. For one week prior to testing, participants emulated the sleep schedule of astronauts, including a strict adherence to 6.5 hours of sleep each night. Naps, caffeine, and sleep medications were also avoided during this time. RESULTS: For EEG data, morphology of beta wave activation in the frontal lobe noticeably changed after light exposure to a more jagged shape with higher frequency and lower amplitude. The control waveform and the waveform measured before light therapy exhibited greater intermixed frequencies of lower value. With regard to reaction time, when light exposure was administered on test days, participants exhibited faster reaction time responses immediately after (374.2 ± 58.1 msec) and 1-hour post (372.7 ± 65.9 msec) compared to before (530.4 ± 120.4 msec) the glasses were worn. CONCLUSION: Blue light exposure integrated into a customized pair of glasses may elicit faster response times and promote greater levels of alertness both immediately after wearing the glasses for 30 min, and one hour after the glasses have been removed
A Mixed-Methods Evaluation of a Gender-Sensitive Rite of Passage Program for Adolescent Males
Introduction
Current gendered health disparities impacting the wellbeing of boys and young men require new early intervention-focussed approaches. Health promotion programs developed with young men’s health needs and preferences in mind commonly report positive outcomes. Male-specific rite of passage programs aim to formally acknowledge the life-stage transition from boyhood to manhood through a holistic focus on identity, community, and social responsibility. While these programs are growing in popularity, there is limited data available on their effectiveness.
Methods
This study undertook a pilot evaluation of the Making of Men rite of passage program in a sample of second-ary school boys (n=61, age M=16.0, SD=0.5) and their accompanying fathers or male mentors (n=47, age M=52.1, SD=5.8 years) providing non-matched pre-test, post-test, alongside follow-up data for participating boys. Qualitative interviews were also undertaken with 15 individuals (5 mothers, 6 staff members, 4 fathers).
Results
Quantitative program feedback indicated acceptability, with most respondents providing positive feedback, particularly from participating fathers. Exploratory quantitative effects indicated potential improvements in subjective social support and open communication among boys. Fathers appeared to report lower confor-mity to traditional masculine norms post-program, in addition to more open communication. Qualitative interviews identified three main themes: enabling relational bonds, creating a men-specific context, and supporting developmental transitions.
Conclusions
Positive program acceptability and promising outcome effects highlighted the present rite of passage program as a promising mechanism for supporting healthy masculine identity development among adolescent males
Strontium as a tracer of weathering processes in a silicate catchment polluted by acid atmospheric inputs, Strengbach, France
This paper determines the weathering and atmospheric contributions of Ca in surface water from a small spruce forested silicate catchment (N–E France) receiving acid atmospheric inputs. The bedrock is a granite with K-feldspar and albite as dominant phases. The calcium content in plagioclase is low and the Ca/Na ratio in surface water is high, reflecting other sources of calcium from those expected from the weathering of major mineral phases. The biotite content is low. Only traces of apatite were detected while no calcite was found in spite of a major hydrothermal event having affected the granite. The strontium isotopic ratio 87Sr/86Sr and Sr content was used as a tracer of weathering and was determined in minerals and bulk bedrock, open field precipitation, throughfall, soil solution, spring and stream water. The Sr isotopic ratio of the reacting weathering end-member was predicted by simulating the alteration of the granite minerals by incorporating strontium into the water–rock interaction kinetic code KINDIS. In the early stages of water–rock interaction, K-feldspar and biotite strongly influence the isotopic composition of the weathering solution whereas, the Na-rich plagioclase appears to be the main long-term reactive weathering end-member. Approximately 50% of dissolved Sr in streamwater are atmospherically derived. The 87Sr/86Sr ratios of exchangeable Sr in the fine fraction at 1-m depth from a soil profile indicate that the amount of exchangeable Sr seems essentially controlled by atmospheric inputs. The exception is the deep saprolite where weathering processes could supply the Sr (and Ca). Na-Plagioclase weathering obviously control the chemistry and the isotopic composition of surface waters. The weathering of trace mineral plays a secondary role, the exception is for apatite when plagioclase is absent. Our hydrochemical, mineralogical and isotopic investigations show that a major part of the strong Ca losses detected in catchment hydrochemical budgets that result from the neutralization of acid precipitation has an atmospheric origin. Consequently, in the long term, in such areas, the availability of such an exchangeable base cation might be strongly limited and surface waters consequently acidified
Electric Field Tunability of Photoluminescence from a Hybrid Peptide-Plasmonic Metal Microfabricated Chip
Enhancement of fluorescence through the application of plasmonic metal nanostructures has gained substantial research attention due to the widespread use of fluorescence-based measurements and devices. Using a microfabricated plasmonic silver nanoparticle-organic semiconductor platform, we show experimentally the enhancement of fluorescence intensity achieved through electro-optical synergy. Fluorophores located sufficiently near silver nanoparticles are combined with diphenylalanine nanotubes (FFNTs) and subjected to a DC electric field. It is proposed that the enhancement of the fluorescence signal arises from the application of the electric field along the length of the FFNTs, which stimulates the pairing of low-energy electrons in the FFNTs with the silver nanoparticles, enabling charge transport across the metal-semiconductor template that enhances the electromagnetic field of the plasmonic nanoparticles. Many-body perturbation theory calculations indicate that, furthermore, the charging of silver may enhance its plasmonic performance intrinsically at particular wavelengths, through band-structure effects. These studies demonstrate for the first time that field-activated plasmonic hybrid platforms can improve fluorescence-based detection beyond using plasmonic nanoparticles alone. In order to widen the use of this hybrid platform, we have applied it to enhance fluorescence from bovine serum albumin and Pseudomonas fluorescens. Significant enhancement in fluorescence intensity was observed from both. The results obtained can provide a reference to be used in the development of biochemical sensors based on surface-enhanced fluorescence.Science Foundation IrelandEuropean Regional Development Fund (ERDF)Sustainable Energy Authority of Ireland (SEAI
Damage patterns, stress rotations and pore fluid pressures in strike-slip fault zones
Active faults unfavorably oriented with respect to the regional maximum compressive stress have been labeled as "weak." The seismic hazards posed by these faults make understanding this apparent weakness a priority. Stress rotations in these fault zones, together with an increase in mean stress, could enable high pore fluid pressures to weaken a fault zone. Such a model requires a foundation in the physics and mechanics of damage. This paper presents a new model for stress rotations in fault zones by combining the Effective Medium Theory with anisotropic poroelasticity. This approach enables the quantitative characterization of crack damage and the prediction of progressive changes in the elastic properties of rocks across the fault zone. The processes of fault growth and wear will lead to distinct patterns of crack damage, with different effects on the elastic properties. Elevated pore fluid pressures have long been known to change the effective normal and shear stresses of anisotropic rocks, and this work incorporates these effects into a multilayer fault zone model. It is shown that high pore fluid pressures in the anisotropic rocks of the core zone can generate large stress rotations (i.e., more fault-parallel), and increases in mean stress, sufficient to weaken the fault. Stress rotations in the damage zones of unfavorably oriented faults tend to be away from the fault (i.e., more fault-normal) for likely combinations of damage patterns and pore fluid pressure
Origin of strange metallic phase in cuprate superconductors
The origin of strange metallic phase is shown to exist due to these two
conditions---(i) the electrons are strongly interacting such that there are no
band and Mott-Hubbard gaps, and (ii) the electronic energy levels are crossed
in such a way that there is an electronic energy gap between two energy levels
associated to two different wave functions. The theory is also exploited to
explain (i) the upward- and downward-shifts in the -linear resistivity
curves, and (ii) the spectral weight transfer observed in the soft X-ray
absorption spectroscopic measurements of the La-Sr-Cu-O Mott insulator.Comment: To be published in J. Supercond. Nov. Mag
Pregnancy-Associated Hypertension in Glucose-Intolerant Pregnancy and Subsequent Metabolic Syndrome
To evaluate whether pregnancy-associated hypertension (preeclampsia or gestational hypertension), among women with varying degrees of glucose intolerance during pregnancy is associated with maternal metabolic syndrome 5-10 years later
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