Investigation ofδ18Oandδ2Hin the Namoi River catchment—elucidating recharge sources and the extent of sur-face water/groundwater interaction

Stable isotopes 18O and 2H were analysed in water samples from rainfall, surface water and groundwater within the semi-arid Namoi River catchment in NSW, Australia.The isotopic composition of rainfall events and groundwater samples plot along the Local Meteoric Water Line (LMWL). In contrast, the surface water samples of the Namoi River clearly show signs of evaporative enrichment and plot on a Local Evaporation Line (LEL) constructed for the area based on δ18O and δ2H time-series for surface waters of the Namoi River. The river samples have a distinctly lower slope than the LMWL which is due to evaporation. Shallow groundwater near the Namoi River shows considerable enrichment compared to average groundwater signatures and plots in between the LMWL and the LEL on a δ2H vs. δ18O graph. These results clearly indicate that the Namoi River is recharging the shallow aquifer system. Conversely, the isotopic composition of surface water in the tributaries of Maules and Horsearm creeks are similar to groundwater indicating that these creeks are receiving groundwater discharge. This study reveals many complex hydrological processes occurring in the catchment. It would not have been possible to elucidate these processes without the use of stable isotope data

The Effects of Trunk Muscle Training on Physical Fitness and Sport-Specific Performance in Young and Adult Athletes: A Systematic Review and Meta-Analysis.

Background The role of trunk muscle training (TMT) for physical ftness (e.g., muscle power) and sport-specifc performance measures (e.g., swimming time) in athletic populations has been extensively examined over the last decades. However, a recent systematic review and meta-analysis on the efects of TMT on measures of physical ftness and sport-specifc performance in young and adult athletes is lacking. Objective To aggregate the efects of TMT on measures of physical ftness and sport-specifc performance in young and adult athletes and identify potential subject-related moderator variables (e.g., age, sex, expertise level) and training-related programming parameters (e.g., frequency, study length, session duration, and number of training sessions) for TMT efects. Data Sources A systematic literature search was conducted with PubMed, Web of Science, and SPORTDiscus, with no date restrictions, up to June 2021. Study Eligibility Criteria Only controlled trials with baseline and follow-up measures were included if they examined the efects of TMT on at least one measure of physical ftness (e.g., maximal muscle strength, change-of-direction speed (CODS)/ agility, linear sprint speed) and sport-specifc performance (e.g., throwing velocity, swimming time) in young or adult competitive athletes at a regional, national, or international level. The expertise level was classifed as either elite (competing at national and/or international level) or regional (i.e., recreational and sub-elite). Study Appraisal and Synthesis Methods The methodological quality of TMT studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. A random-efects model was used to calculate weighted standardized mean diferences (SMDs) between intervention and active control groups. Additionally, univariate sub-group analyses were independently computed for subject-related moderator variables and training-related programming parameters. Results Overall, 31 studies with 693 participants aged 11–37 years were eligible for inclusion. The methodological quality of the included studies was 5 on the PEDro scale. In terms of physical ftness, there were signifcant, small-to-large efects of TMT on maximal muscle strength (SMD =0.39), local muscular endurance (SMD =1.29), lower limb muscle power (SMD=0.30), linear sprint speed (SMD =0.66), and CODS/agility (SMD =0.70). Furthermore, a signifcant and moderate TMT efect was found for sport-specifc performance (SMD=0.64). Univariate sub-group analyses for subject-related moderator variables revealed signifcant efects of age on CODS/agility (p=0.04), with signifcantly large efects for children (SMD=1.53, p=0.002). Further, there was a signifcant efect of number of training sessions on muscle power and linear sprint speed (p≤0.03), with signifcant, small-to-large efects of TMT for>18 sessions compared to≤18 sessions (0.45≤SMD≤0.84, p≤0.003). Additionally, session duration signifcantly modulated TMT efects on linear sprint speed, CODS/agility, and sport-specifc performance (p≤0.05). TMT with session durations≤30 min resulted in signifcant, large efects on linear sprint speed and CODS/agility (1.66≤SMD≤2.42, p≤0.002), whereas session durations>30 min resulted in signifcant, large efects on sport-specifc performance (SMD=1.22, p=0.008). Conclusions Our fndings indicate that TMT is an efective means to improve selected measures of physical ftness and sportspecifc performance in young and adult athletes. Independent sub-group analyses suggest that TMT has the potential to improve CODS/agility, but only in children. Additionally, more (>18) and/or shorter duration (≤30 min) TMT sessions appear to be more efective for improving lower limb muscle power, linear sprint speed, and CODS/agility in young or adult competitive athletes.publishedVersio

Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer

The terrestrial subsurface is the largest source of freshwater globally. The organic carbon contained within it and processes controlling its concentration remain largely unknown. The global median concentration of dissolved organic carbon (DOC) in groundwater is low compared to surface waters, suggesting significant processing in the subsurface. Yet the processes that remove this DOC in groundwater are not fully understood. The purpose of this study was to investigate the different sources and processes influencing DOC in a shallow anoxic coastal aquifer. Uniquely, this study combines liquid chromatography organic carbon detection with organic (δ13CDOC) carbon isotope geochemical analyses to fingerprint the various DOC sources that influence the concentration, carbon isotopic composition, and character with respect to distance from surface water sources, depth below surface, and inferred groundwater residence time (using 3H activities) in groundwater. It was found that the average groundwater DOC concentration was 5 times higher (5 mg L−1) than the global median concentration and that the concentration doubled with depth at our site, but the chromatographic character did not change significantly. The anoxic saturated conditions of the aquifer limited the rate of organic matter processing, leading to enhanced preservation and storage of the DOC sources from peats and palaeosols contained within the aquifer. All groundwater samples were more aromatic for their molecular weight in comparison to other lakes, rivers and surface marine samples studied. The destabilization or changes in hydrology, whether by anthropogenic or natural processes, could lead to the flux of up to 10 times more unreacted organic carbon from this coastal aquifer compared to deeper inland aquifers

Smc5/6 coordinates formation and resolution of joint molecules with chromosome morphology to ensure meiotic divisions

During meiosis, Structural Maintenance of Chromosome (SMC) complexes underpin two fundamental features of meiosis: homologous recombination and chromosome segregation. While meiotic functions of the cohesin and condensin complexes have been delineated, the role of the third SMC complex, Smc5/6, remains enigmatic. Here we identify specific, essential meiotic functions for the Smc5/6 complex in homologous recombination and the regulation of cohesin. We show that Smc5/6 is enriched at centromeres and cohesin-association sites where it regulates sister-chromatid cohesion and the timely removal of cohesin from chromosomal arms, respectively. Smc5/6 also localizes to recombination hotspots, where it promotes normal formation and resolution of a subset of joint-molecule intermediates. In this regard, Smc5/6 functions independently of the major crossover pathway defined by the MutLγ complex. Furthermore, we show that Smc5/6 is required for stable chromosomal localization of the XPF-family endonuclease, Mus81-Mms4Eme1. Our data suggest that the Smc5/6 complex is required for specific recombination and chromosomal processes throughout meiosis and that in its absence, attempts at cell division with unresolved joint molecules and residual cohesin lead to severe recombination-induced meiotic catastroph

Effects of sex, age, and visits on receipt of preventive healthcare services: a secondary analysis of national data

BACKGROUND: Sex and age may exert a combined influence on receipt of preventive services with differences due to number of ambulatory care visits. METHODS: We used nationally representative data to determine weighted percentages and adjusted odds ratios of men and women stratified by age group who received selected preventive services. The presence of interaction between sex and age group was tested using adjusted models and retested after adding number of visits. RESULTS: Men were less likely than women to have received blood pressure screening (aOR 0.44;0.40–0.50), cholesterol screening (aOR 0.72;0.65–0.79), tobacco cessation counseling (aOR 0.66;0.55–0.78), and checkups (aOR 0.53;0.49–0.57). In younger age groups, men were particularly less likely than women to have received these services. In adjusted models, this observed interaction between sex and age group persisted only for blood pressure measurement (p = .016) and routine checkups (p < .001). When adjusting for number of visits, the interaction of age on receipt of blood pressure checks was mitigated but men were still overall less likely to receive the service. CONCLUSION: Men are significantly less likely than women to receive certain preventive services, and younger men even more so. Some of this discrepancy is secondary to a difference in number of ambulatory care visits

Carpal tunnel syndrome and the use of computer mouse and keyboard: A systematic review

<p>Abstract</p> <p>Background</p> <p>This review examines evidence for an association between computer work and carpal tunnel syndrome (CTS).</p> <p>Methods</p> <p>A systematic review of studies of computer work and CTS was performed. Supplementary, longitudinal studies of low force, repetitive work and CTS, and studies of possible pathophysiological mechanisms were evaluated.</p> <p>Results</p> <p>Eight epidemiological studies of the association between computer work and CTS were identified. All eight studies had one or more limitation including imprecise exposure and outcome assessment, low statistical power or potentially serious biases. In three of the studies an exposure-response association was observed but because of possible misclassification no firm conclusions could be drawn. Three of the studies found risks below 1. Also longitudinal studies of repetitive low-force non-computer work (n = 3) were reviewed but these studies did not add evidence to an association. Measurements of carpal tunnel pressure (CTP) under conditions typically observed among computer users showed pressure values below levels considered harmful. However, during actual mouse use one study showed an increase of CTP to potentially harmful levels. The long term effects of prolonged or repeatedly increased pressures at these levels are not known, however.</p> <p>Conclusion</p> <p>There is insufficient epidemiological evidence that computer work causes CTS.</p

First Neutrino Observations from the Sudbury Neutrino Observatory

The first neutrino observations from the Sudbury Neutrino Observatory are presented from preliminary analyses. Based on energy, direction and location, the data in the region of interest appear to be dominated by 8B solar neutrinos, detected by the charged current reaction on deuterium and elastic scattering from electrons, with very little background. Measurements of radioactive backgrounds indicate that the measurement of all active neutrino types via the neutral current reaction on deuterium will be possible with small systematic uncertainties. Quantitative results for the fluxes observed with these reactions will be provided when further calibrations have been completed.Comment: Latex, 7 pages, 10 figures, Invited paper at Neutrino 2000 Conference, Sudbury, Canada, June 16-21, 2000 to be published in the Proceeding

Binary Tomography Reconstruction by Particle Aggregation

This paper presents a novel reconstruction algorithm for bi- nary tomography based on the movement of particles. Particle Aggregate Reconstruction Technique (PART) supposes that pixel values are particles, and that the particles can diffuse through the image, sticking together in regions of uniform pixel value known as aggregates. The algorithm is tested on four phantoms of varying sizes and numbers of forward projections and compared to a random search algorithm and to SART, a standard algebraic reconstruction method. PART, in this small study, is shown to be capable of zero error reconstruction and compares favourably with SART and random search

Substrate Profiling of Tobacco Etch Virus Protease Using a Novel Fluorescence-Assisted Whole-Cell Assay

Site-specific proteolysis of proteins plays an important role in many cellular functions and is often key to the virulence of infectious organisms. Efficient methods for characterization of proteases and their substrates will therefore help us understand these fundamental processes and thereby hopefully point towards new therapeutic strategies. Here, a novel whole-cell in vivo method was used to investigate the substrate preference of the sequence specific tobacco etch virus protease (TEVp). The assay, which utilizes protease-mediated intracellular rescue of genetically encoded short-lived fluorescent substrate reporters to enhance the fluorescence of the entire cell, allowed subtle differences in the processing efficiency of closely related substrate peptides to be detected. Quantitative screening of large combinatorial substrate libraries, through flow cytometry analysis and cell sorting, enabled identification of optimal substrates for TEVp. The peptide, ENLYFQG, identical to the protease's natural substrate peptide, emerged as a strong consensus cleavage sequence, and position P3 (tyrosine, Y) and P1 (glutamine, Q) within the substrate peptide were confirmed as being the most important specificity determinants. In position P1′, glycine (G), serine (S), cysteine (C), alanine (A) and arginine (R) were among the most prevalent residues observed, all known to generate functional TEVp substrates and largely in line with other published studies stating that there is a strong preference for short aliphatic residues in this position. Interestingly, given the complex hydrogen-bonding network that the P6 glutamate (E) is engaged in within the substrate-enzyme complex, an unexpectedly relaxed residue preference was revealed for this position, which has not been reported earlier. Thus, in the light of our results, we believe that our assay, besides enabling protease substrate profiling, also may serve as a highly competitive platform for directed evolution of proteases and their substrates

Potential of Macrostomum lignano to recover from γ-ray irradiation

Stem cells are the only proliferating cells in flatworms and can be eliminated by irradiation with no damage to differentiated cells. We investigated the effect of fractionated irradiation schemes on Macrostomum lignano, namely, on survival, gene expression, morphology and regeneration. Proliferating cells were almost undetectable during the first week post-treatment. Cell proliferation and gene expression were restored within 1 month in a dose-dependent manner following exposure to up to 150 Gy irradiation. During recovery, stem cells did not cross the midline but were restricted within lateral compartments. An accumulated dose of 210 Gy resulted in a lethal phenotype. Our findings demonstrate that M. lignano represents a suitable model system for elucidating the effect of irradiation on the stem cell system in flatworms and for improving our understanding of the recovery potential of severely damaged stem-cell systems