ESR Fine Structure of Manganese Ions in Zeolite A Detects Strong Variations of the Coordination Environment

The electron spin resonance spectra of Mn 2+ exchanged zeolite A have been investigated as a function of the monovalent co-cation (K + ,Na + ,Li + ,Cs + ,or NH4 + ), Mn 2+ content, recording frequency, and temperature. Three new Mn 2+ species are observed with a well-resolved fine structure; this allows for the first time a direct quantitative determination of the zero-field splitting (ZFS) parameters in zeolites. In hydrated zeolites, three ESR active Mn 2+ species are observed, characterized by different values for the ZFS parameter D. Species I has D ) 0.035 cm -1 . Species II is closer to a regular octahedron, with D ) 0.010 cm -1 . Species III, with D ) 0.14 cm -1 , is in a strongly axially distorted coordination. Species I is dominant in MnKA, MnCsA, and MnNH4A, while II and III are found in MnNaA and MnLiA. In fully dehydrated zeolites, two species are observed. Species IV has a small hyperfine constant A and is present in dry NaA and KA. Species V is observed in dry LiA; it has axial symmetry with a large, temperature-dependent D. Species V probably represents Mn 2+ in a 3-fold coordination in a 6-ring. In partially hydrated zeolites, a tetrahedral species VI is observed. The spectroscopic data elucidate the location of manganese-( II) ions in zeolite A, particularly at relatively low metal loadings

Is Training Load Associated with Symptoms of Overuse Injury in Dancers? A Prospective Observational Study

Overuse injuries in dance are extremely common and often difficult to treat. High training load and dancing with pain are frequently regarded as risk factors for musculoskeletal injuries in professional dancers. The aims of this study were to assess for: 1. any association between training load (TL) and symptoms of overuse injury in professional dancers, and 2. any difference between the number of "time-loss" injuries and injuries causing significant symptoms not leading to decreased performance time. Twenty-one dancers from a professional contemporary dance company were followed for 7 weeks. They completed the dance-specific Self-Estimated Functional Inability because of Pain (SEFIP) questionnaire on a weekly basis to quantify musculoskeletal pain. Their TL was calculated by multiplying the Ratings of Perceived Exertion scale (RPE Borg CR10) by the daily training time. Associations between TL and SEFIP scores, recorded on a weekly basis, were evaluated using a mixed linear model with repeated measurements. No significant association was found between TL and severity of musculoskeletal pain. However, the TL of the dancers with no symptoms of overuse-injury, SEFIP = 0, was significantly lower compared to the dancers with symptoms, SEFIP > 0; p = 0.02. No time loss because of injury was reported during the study period. There were 251 symptoms of overuse injury reported, and 67% of the recorded time was danced with pain. It is concluded that dancers without musculoskeletal pain had lower TLs. While no time-loss injuries were found, two-third of the participants danced with pain during this 7-week period

Purification and characterization of the alanine aminotransferase from the hyperthermophilic Archaeon Pyrococcus furiosus and its role in alanine production

Alanine aminotransferase (AlaAT) was purified from cell extracts of the hyperthermophilic archaeon Pyrococcus furiosus by multistep chromatography. The enzyme has an apparent molecular mass of 93.5 kDa, as estimated by gel filtration, and consists of two identical subunits of 46 kDa, as deduced by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the gene sequence. The AlaAT displayed a broader substrate specificity than AlaATs from eukaryal sources and exhibited significant activity with alanine, glutamate, and aspartate with either 2-oxoglutarate or pyruvate as the amino acceptor. Optimal activity was found in the pH range of 6.5 to 7.8 and at a temperature of over 95°C. The N-terminal amino acid sequence of the purified AlaAT was determined and enabled the identification of the gene encoding AlaAT (aat) in the P. furiosus genome database. The gene was expressed in Escherichia coli, and the recombinant enzyme was purified. The pH and temperature dependence, molecular mass, and kinetic parameters of the recombinant were indistinguishable from those of the native enzyme from P. furiosus. The kcat/Km values for alanine and pyruvate formation were 41 and 33 s1 mM1, respectively, suggesting that the enzyme is not biased toward either the formation of pyruvate, or alanine. Northern analysis identified a single 1.2-kb transcript for the aat gene. In addition, both the aat and gdh (encoding the glutamate dehydrogenase) transcripts appear to be coregulated at the transcriptional level, because the expression of both genes was induced when the cells were grown on pyruvate. The coordinated control found for the aat and gdh genes is in good agreement with these enzymes acting in a concerted manner to form an electron sink in P. furiosus

High knee loading in male adolescent pre-professional football players: Effects of a targeted training programme

Objective: To assess whether targeted neuromuscular exercises can decrease knee loading of adolescent pre-professional footballers with high knee loading as identified with the field-based Drop Vertical Jump Test (DVJT). Design: Prospective controlled trial, conducted between August and November 2016 at Erasmus Medical Centre, The Netherlands. Methods: Pre-professional football players (aged 14–21 years) were evaluated at baseline and after 12 weeks follow-up with the field-based DVJT. The field-based DVJT is a standardised test in which a player drops from a box and jumps up immediately after landing; knee load is calculated based on five parameters. Players with high knee load (probability ≥ 0.75) from one club performed regular training(control group), and players with high knee load from another other club performed targeted neuromuscular exercises for 12 weeks (intervention group). The difference of change in knee load between both groups after 12 weeks was the primary outcome measure. Results: Of 107 eligible players, 75 had a high knee loading. Knee loading decreased in both groups after 12 weeks of training, but change in probability of high knee load was not significantly different between both groups (95% Confidence Interval [−0.012–0.082], p = 0.139). Conclusion: Targeted neuromuscular exercises had no additional effect in decreasing knee loading of adolescent male pre-professional football players compared to regular training. Trial registration number: The Netherlands Trial Register (ID number: 6044)

Reliability of pelvimetry is affected by observer experience but not by breed and sex : a cross-sectional study in beef cattle

Pelvis size plays an important role to prevent dystocia in cattle caused by the foetomaternal disproportion in commonly primiparous females. The reproducibility and repeatability are two important aspects for the reliability of the measurements to use in the selection of cattle for culling. Pelvic measures were taken with a Rice pelvimeter from 224 young cattle (180 females and 44 males) of four beef breeds in South Africa. One experienced and two inexperienced observers each measured pelvic height and width twice. The proportion measurements with a maximum difference of 0.5 cm within animal compared with the first measurement by the experienced observer are around 80% and by the inexperienced observers around 50% for pelvic height and around 60% for pelvic width. Breed and sex do not affect the reliability of pelvimetry by an experienced observer. Under- and overestimation of pelvis size were observed in inexperienced observers, which seems to be unrelated to breed and sex.http://wileyonlinelibrary.com/journal/rdahj2021Animal and Wildlife SciencesProduction Animal Studie

Automatic coronary artery calcium scoring on radiotherapy planning CT Scans of breast cancer patients: Reproducibility and association with traditional cardiovascular risk factors

Objectives Coronary artery calcium (CAC) is a strong and independent predictor of cardiovascular disease (CVD) risk. This study assesses reproducibility of automatic CAC scoring on radiotherapy planning computed tomography (CT) scans of breast cancer patients, and examines its association with traditional cardiovascular risk factors. Methods This study included 561 breast cancer patients undergoing radiotherapy between 2013 and 2015. CAC was automatically scored with an algorithm using supervised pattern recognition, expressed as Agatston scores and categorized into five categories (0, 1-10, 11-100, 101-400, >400). Reproducibility between automatic and manual expert scoring was assessed in 79 patients with automatically determined CAC above zero and 84 randomly selected patients without automatically determined CAC. Interscan reproducibility of automatic scoring was assessed in 294 patients having received two scans (82% on the same day). Association between CAC and CVD risk factors was assessed in 36 patients with CAC scores >100, 72 randomly selected patients with scores 1-100, and 72 randomly selected patients without CAC. Reliability was assessed with linearly weighted kappa and agreement with proportional agreement. Results 134 out of 561 (24%) patients had a CAC score above zero. Reliability of CVD risk categorization between automatic and manual scoring was 0.80 (95% Confidence Interval (CI): 0.74-0.87), and slightly higher for scans with breath-hold. Agreement was 0.79 (95% CI: 0.72-0.85). Interscan reliability was 0.61 (95% CI: 0.50-0.72) with an agreement of 0.84 (95% CI: 0.80-0.89). Ten out of 36 (27.8%) patients with CAC scores above 100 did not have other cardiovascular risk factors. Conclusions Automatic CAC scoring on radiotherapy planning CT scans is a reliable method to assess CVD risk based on Agatston scores. One in four breast cancer patients planned for radiotherapy have elevated CAC score. One in three patients with high CAC scores don't have other CVD risk factors and wouldn't have been identified as high risk

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented