A GEANT4 Study of a Gamma-ray Collimation Array

Proton beam therapy uses high-energy protons to destroy cancer cells which are still uncertain about where in the body they hit. A possible way to answer this question is to detect the gamma rays produced during the irradiation and determine where in the body they are produced. This work investigates the use of collimators to determine where the proton interactions occur. GEANT4 is used to simulate the gamma production of a source interacting with a collimator. Each event simulates a number of gammas obtained as a function of the position along the detector. Repeating for different collimator configurations can thus help determine the best characteristics of a detector device

Strength, jumping, and change of direction speed asymmetries are not associated with athletic performance in elite academy soccer players

The aims of the present study were twofold: 1) to measure inter-limb asymmetries from a battery of fitness tests in youth soccer players and, 2) determine the association between asymmetry and measures of athletic performance. Sixteen elite youth soccer players (14.7 ± 0.2 years) performed a single leg Abalakov test (ABK), change of direction (COD) test over 10 m (5 + 5) and 20 m (10 + 10), and an iso-inertial power test. Subjects also performed 10 m, 20 m and 30 m sprints and a bilateral countermovement jump (CMJ), which were correlated with all ABK, COD and iso-inertial asymmetry scores. A one-way repeated measures ANOVA showed significant differences between inter-limb asymmetry scores across multiple tests (p 0.05) between the different inter-limb asymmetry scores, and between asymmetry scores and athletic performance. These findings show the test-specific nature of asymmetries in youth soccer players, with the iso-inertial power test being the most sensitive in detecting asymmetry. Moreover, the results obtained suggest that inherent asymmetry in young soccer players did not negatively impact their performance

Comparison of a proprioceptive training program on stable base and unstable base

El objetivo de este estudio fue comparar dos programas de entrenamiento propioceptivo sobre base estable (G1) y base inestable (G2). Durante 5 semanas, 18 jugadores de fútbol profesional se sometieron a un programa de entrenamiento propioceptivo, 9 formaron el G1 y 9 G2. Se aplicó el Standard Excursion Balance Test (Test de Estrella) antes y después de la intervención. Los resultados intragrupo mostraron diferencias significativas en las variables ANT.IZDO; ANTLAT.IZDO; POST.D y ANTMED.D (p<0,005) para el G1 y ANT.D; ANT.IZDO; POSTMED.D; POSTMED.IZDO Y MED.D (p <0,005) para el G2. No se hallaron evidencias significativas entre el entrenamiento en base estable y base inestable para la mejora del equilibrio y la estabilidadThe aim is to compare two proprioceptive training programs on a stable (G1) and an unstable (G2) base in terms of balance and stability. During a 5 week period, 18 professional football players underwent a proprioceptive training program, 9 in G1 and the other 9 in G2. The Standard Excursion Balance Test was applied before and after the intervention program. Significant intragroup differences were found in the variables LEFT FRONT, ANTEROLATERAL LEFT (ANTLAT.LEFT), BACK RIGHT and ANTEROMEDIAL RIGHT (ANTMED.RIGHT) (p<0,005) for the G1, and FRONT RIGHT, FRONT LEFT, POSTMED.RIGHT, POSTMED.LEFT and MED.RIGHT (p <0,005) for G2. We conclude that there are no significant differences between the unstable base training and training stable base regarding improvement in balance and stabilit

In vitro Study of the Survival, Reproduction and Morphology of Daphnia pulicaria irradiated with a Low Energy Laser

Daphnia is a genus of crustaceans that is representative of freshwater communities. The species exhibit a high sensitivity to a wide range of toxic compounds so that they have been used internationally as biomonitors in toxicity tests to evaluate ecosystem conditions such as water quality. It is also a model genus in genetics, epigenetics and reproductive ecology. In this work, we used Daphnia pulicaria as a model to measure the effects of low-energy laser irradiation on survival, reproduction, and morphology variables of parental organisms and their offspring. We used (1) a single clone line of organisms to eliminate interindividual genetic variability; (2) individuals from more than 50 generations after the clone line was established, and offspring from the third brood onwards to dissipate maternal and epigenetic effects, and (3) neonates, those individuals of the species that have less than 48 hours of life, because they are the most sensitive stage to optical stimuli. We analyzed number of deaths, longevity, age at first reproduction, number of offspring per week, number of total offspring during all their life cycle, body size, size of the antennules, and length of the apical spine of the 4th and 5th brood of the irradiated individuals, who were exposed to a blue laser stimulus of 405 nm for 25 minutes with a power of 40 mW at a distance of 50 cm, compared to those of the control (non-irradiated) group

Using microbes to recover rare earths with low environmental impact?

Using Microbes to recover Rare Earths with low environmental impact Barbara Palumbo Roe, Simon Gregory, Antoni Milodowski, Julia West, Joanna Wragg British Geological Survey, Nicker Hill, Nottingham NG12 5GG, UK Steve Banwart, Maria Romero González, Wei Huang, Emma Wharfe Kroto Research Institute, University of Sheffield, Sheffield S3 7HQ, UK John Harding, Colin Freeman, Shaun Hall Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, UK Microbes play an important role in the fate and transport of rare earth elements (REE) in relation to the REE exploitation life cycle. A step change in understanding is needed for key mobilisation, concentration and fractionation processes such as bioleaching, biosorption and biomineralisation and how they can 1) be harnessed to recover REE in situ from low grade ores or secondary deposits, and 2) be quantified for reactive transport in environmental risk assessment and management of mining operations. Heap/in-situ leaching methods are relatively low impact mining technologies, requiring less energy (for comminution) and in the case of in-situ leaching have a minimal footprint. Furthermore, biologically-assisted leaching and separation processes represent a more sustainable alternative to chemical processes. We discuss the microbial potential to accelerate dissolution of REEs from source minerals, and how the natural selectivity of mineral and microbial surfaces as ligands for adsorption and biomineralisation of REE dissolved species could be exploited in the recovery of REEs from fluids

Assessment of posttraumatic stress disorder among women after childbirth using the City Birth Trauma Scale in Spain

OBJECTIVE: Postpartum posttraumatic stress disorder (PP-PTSD) affects 3.1-6.3% of women after childbirth. The City Birth Trauma Scale (City-BiTS) is a questionnaire designed to evaluate and diagnose this disorder, according to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria, including the following groups of symptoms characteristic of posttraumatic stress: reexperiencing, avoidance, negative cognitions and mood, and hyperarousal. The aim of the present study was to evaluate the psychometric properties of the Spanish-language version of this questionnaire (City-BiTS-S), based on a community sample of Spanish women. METHOD: A total of 207 mothers, recruited at three health centers in southern Spain, completed the City-BiTS-S questionnaire and provided sociodemographic and obstetric data. RESULTS: Exploratory factor analysis of the data replicated the two-factor structure reported in previous studies that explained 47.9% of the variance: Factor 1 of general symptoms and Factor 2 of birth-related symptoms. Both City-BiTS-S (Cronbach's alpha = .90) and the two factors (Cronbach's alpha for Factor 1 = 0.89; Cronbach's alpha for Factor 2 = 0.82) presented high internal consistency. Rasch analysis confirmed the unidimensionality of the two factors as valid subscales of the PP-PTSD. Results suggested reducing response options, reviewing Item 8, and rewording Item 3 in the Spanish version. CONCLUSIONS: The City-BiTS-S presents appropriate psychometric properties to measure symptoms of PP-PTSD. Nevertheless, further research is recommended to confirm its validity in a clinical population and in different medical approaches to the birth process

Molecular and Biochemical Methods Useful for the Epigenetic Characterization of Chromatin-Associated Proteins in Bivalve Molluscs

Bivalve molluscs constitute a ubiquitous taxonomic group playing key functions in virtually all ecosystems, and encompassing critical commercial relevance. Along with a sessile and filter-feeding lifestyle in most cases, these characteristics make bivalves model sentinel organisms routinely used for environmental monitoring studies in aquatic habitats. The study of epigenetic mechanisms linking environmental exposure and specific physiological responses (i.e., environmental epigenetics) stands out as a very innovative monitoring strategy, given the role of epigenetic modifications in acclimatization and adaptation. Furthermore, the heritable nature of many of those modifications constitutes a very promising avenue to explore the applicability of epigenetic conditioning and selection in management and restoration strategies. Chromatin provides a framework for the study of environmental epigenetic responses. Unfortunately, chromatin and epigenetic information are very limited in most non-traditional model organisms and even completely lacking in most environmentally and ecologically relevant organisms. The present work aims to provide a comprehensive and reproducible experimental workflow for the study of bivalve chromatin. First, a series of guidelines for the molecular isolation of genes encoding chromatin-associated proteins is provided, including information on primers suitable for conventional PCR, Rapid Amplification of cDNA Ends (RACE), genome walking and quantitative PCR (qPCR) experiments. This section is followed by the description of methods specifically developed for the analysis of histone and SNBP proteins in different bivalve tissues, including protein extraction, purification, separation and immunodetection. Lastly, information about available antibodies, their specificity and performance is also provided. The tools and protocols described here complement current epigenetic analyses (usually limited to DNA methylation) by incorporating the study of structural elements modulating chromatin dynamics

Interventions to treat fear of childbirth in pregnancy: A systematic review and meta-analysis

Background Between 5% and 14% of women suffer from fear of childbirth (FOC) which is associated with difficulties during birth and in postnatal psychological adjustment. Therefore, effective interventions are needed to improve outcomes for women. A systematic review and meta-analysis was used to identify effective interventions for treating women with FOC. Methods Literature searches were undertaken on online databases. Hand searches of reference lists were also carried out. Studies were included in the review if they recruited women with FOC and aimed to reduce FOC and/or improve birth outcomes. Data were synthesised qualitatively and quantitatively using meta-analysis. The literature searches provided a total of 4474 citations. Results After removing duplicates and screening through abstracts, titles and full texts, 66 papers from 48 studies were identified for inclusion in the review. Methodological quality was mixed with 30 out of 48 studies having a medium risk of bias. Interventions were categorised into six broad groups: Cognitive behavioural therapy, other talking therapies, antenatal education, enhanced midwifery care, alternative interventions and interventions during labour. Results from the meta-analysis showed that most interventions reduced FOC, regardless of the approach (mean effect size =-1.27; z =-4.53, p < 0.0001) and that other talking therapies may reduce caesarean section rates (OR 0.48, 95% CI 0.48-0.90). Conclusions Poor methodological quality of studies limits conclusions that can be drawn; however, evidence suggests that most interventions investigated reduce FOC. Future high-quality randomised controlled trials are needed so that clear conclusions can be made

Evolution of trees and mycorrhizal fungi intensifies silicate mineral weathering.

Forested ecosystems diversified more than 350 Ma to become major engines of continental silicate weathering, regulating the Earth's atmospheric carbon dioxide concentration by driving calcium export into ocean carbonates. Our field experiments with mature trees demonstrate intensification of this weathering engine as tree lineages diversified in concert with their symbiotic mycorrhizal fungi. Preferential hyphal colonization of the calcium silicate-bearing rock, basalt, progressively increased with advancement from arbuscular mycorrhizal (AM) to later, independently evolved ectomycorrhizal (EM) fungi, and from gymnosperm to angiosperm hosts with both fungal groups. This led to 'trenching' of silicate mineral surfaces by AM and EM fungi, with EM gymnosperms and angiosperms releasing calcium from basalt at twice the rate of AM gymnosperms. Our findings indicate mycorrhiza-driven weathering may have originated hundreds of millions of years earlier than previously recognized and subsequently intensified with the evolution of trees and mycorrhizas to affect the Earth's long-term CO(2) and climate history

Characterization of mussel H2A.Z.2: a new H2A.Z variant preferentially expressed in germinal tissues from Mytilus

Histones are the fundamental constituents of the eukaryotic chromatin, facilitating the physical organization of DNA in chromosomes and participating in the regulation of its metabolism. The H2A family displays the largest number of variants among core histones, including the renowned H2A.X, macroH2A, H2A.B (Bbd) and H2A.Z. This latter variant is especially interesting due to its regulatory role and its differentiation into two functionally divergent variants (H2A.Z.1 and H2A.Z.2), further specializing the structure and function of vertebrate chromatin. In the present work we describe, for the first time, the presence of a second H2A.Z variant (H2A.Z.2) in the genome of a non-vertebrate animal, the mussel Mytilus. The molecular and evolutionary characterization of mussel H2A.Z.1 and H2A.Z.2 histones is consistent with their functional specialization, supported on sequence divergence at promoter and coding regions as well as on varying gene expression patterns. More precisely, the expression of H2A.Z.2 transcripts in gonadal tissue and its potential upregulation in response to genotoxic stress might be mirroring the specialization of this variant in DNA repair. Overall, the findings presented in this work complement recent reports describing the widespread presence of other histone variants across eukaryotes, supporting an ancestral origin and conserved role for histone variants in chromatin