1,999 research outputs found
Charge Symmetry Breaking and QCD
Charge symmetry breaking (CSB) in the strong interaction occurs because of
the difference between the masses of the up and down quarks. The use of
effective field theories allows us to follow this influence of confined quarks
in hadronic and nuclear systems. The progress in observing and understanding
CSB is reviewed with particular attention to the recent successful observations
of CSB in measurements involving the production of a single neutral pion and to
the related theoretical progress.Comment: 41 pages, 10 figures, for Nov. 2006 edition Annual Review of Nuclear
and Particle Physic
An Investigation of Stress Dependent Atomic Oxygen Erosion of Black Kapton Observed on MISSE 6
Black Kapton XC polyimide was flown as part of the Polymer Film Tensile Experiment (PFTE) on Materials International Space Station Experiment 6 (MISSE 6). The purpose of the experiment was to expose a variety of polymer films, typical of those used for thermal control blankets or supporting membranes on Earth orbiting spacecraft, to the low Earth orbital (LEO) environment under both relaxed and tension conditions. Black Kapton XC under tensile stress experienced a higher erosion rate during exposure in LEO than the same material that was flown in a relaxed condition. Testing conducted to determine the magnitude of the stress and erosion dependence using a ground-based thermal energy atomic oxygen plasma showed a slight dependence of erosion yield on stress for Kapton HN and Black Kapton XC, but not to the extent observed on MISSE 6. More testing is needed to isolate the factors present in LEO that cause stress dependent erosion
CORRELATIONS AMONG GRAIN CHARACTERISTICS USED TO DETERMINE THE EFFECTS OF ROUGH RICE STORAGE TIME AND TEMPERATURE ON AROMATIC RICE QUALITY
Summary statistics and corresponding Spearman correlation coefficients are illustrated for various subsets of aromatic rough rice storage time and temperature data from (a) the College Station texture sensory panel, (b) the New Orleans aroma and flavor sensory panel, and (c) the Beaumont USDA-ARS Rice Quality Laboratory. These correlations represent the inclinations of seemingly-related measures of several attributes to "move together," acting as an indicator of their associations with or impacts on one another.Crop Production/Industries,
CORRELATIONS AMONG GRAIN CHARACTERISTICS USED TO DETERMINE THE EFFECTS OF MILLED RICE STORAGE TIME AND TEMPERATURE ON AROMATIC RICE QUALITY
Summary statistics and corresponding Spearman correlation coefficients are illustrated for various subsets of aromatic milled rice storage time and temperature data from (a) the College Station texture sensory panel, (b) the New Orleans aroma and flavor sensory panel, and (c) the Beaumont USDA-ARS Rice Quality Laboratory. These correlations represent the inclinations of seemingly-related measures of several attributes to "move together," acting as an indicator of their associations with or impacts on one another.Crop Production/Industries,
Effect of increased quadriceps tensile stiffness on peak anterior cruciate ligament strain during a simulated pivot landing
ACL injury prevention programs often involve strengthening the knee muscles. We posit that an unrecognized benefit of such training is the associated increase in the tensile stiffness of the hypertrophied muscle. We tested the hypothesis that an increased quadriceps tensile stiffness would reduce peak anteromedial bundle (AMâ)ACL relative strain in female knees. Twelve female cadaver knees were subjected to compound impulsive twoâtimes body weight loads in compression, flexion, and internal tibial torque beginning at 15° flexion. Knees were equipped with modifiable custom springs to represent the nonlinear rapid stretch behavior of a normal and increased stiffness female quadriceps (i.e., 33% greater stiffness). Peak AMâACL relative strain was measured using an in situ transducer while muscle forces and tibiofemoral kinematics and kinetics were recorded. A 3D ADAMSâą dynamic biomechanical knee model was used in silico to interpret the experimental results which were analyzed using a repeatedâmeasures Wilcoxon test. Female knees exhibited a 16% reduction in peak AMâACL relative strain and 21% reduction in change in flexion when quadriceps tensile stiffness was increased by 33% (mean (SD) difference: 0.97% (0.65%), p â=â0.003). We conclude that increased quadriceps tensile stiffness reduces peak ACL strain during a controlled study simulating a pivot landing. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:423â430, 2014.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102663/1/jor22531.pd
MISSE 6 Polymer Film Tensile Experiment
The Polymer Film Tensile Experiment (PFTE) was flown as part of Materials International Space Station Experiment 6 (MISSE 6). The purpose of the experiment was to expose a variety of polymer films to the low Earth orbital environment under both relaxed and tension conditions. The polymers selected are those commonly used for spacecraft thermal control and those under consideration for use in spacecraft applications such as sunshields, solar sails, and inflatable and deployable structures. The dog-bone shaped samples of polymers that were flown were exposed on both the side of the MISSE 6 Passive Experiment Container (PEC) that was facing into the ram direction (receiving atomic oxygen, ultraviolet (UV) radiation, ionizing radiation, and thermal cycling) and the wake facing side (which was supposed to have experienced predominantly the same environmental effects except for atomic oxygen which was present due to reorientation of the International Space Station). A few of the tensile samples were coated with vapor deposited aluminum on the back and wired to determine the point in the flight when the tensile sample broke as recorded by a change in voltage that was stored on battery powered data loggers for post flight retrieval and analysis. The data returned on the data loggers was not usable. However, post retrieval observation and analysis of the samples was performed. This paper describes the preliminary analysis and observations of the polymers exposed on the MISSE 6 PFTE
The Oak Ridge Polycystic Kidney mouse: Modeling ciliopathies of mice and men
The Oak Ridge Polycystic Kidney (ORPK) mouse was described nearly 14 years ago as a model for human recessive polycystic kidney disease. The ORPK mouse arose through integration of a transgene into an intron of the Ift88 gene resulting in a hypomorphic allele (Ift88(Tg737Rpw)). The Ift88(Tg737Rp omega) mutation impairs intraflagellar transport (IFT), a process required for assembly of motile and immotile cilia. Historically, the primary immotile cilium was thought to have minimal importance for human health; however, a rapidly expanding number of human disorders have now been attributed to ciliary defects. Importantly, many of these phenotypes are present and can be analyzed using the ORPK mouse. In this review, we highlight the research conducted using the OPRK mouse and the phenotypes shared with human cilia disorders. Furthermore, we describe an additional follicular dysplasia phenotype in the ORPK mouse, which alongside the ectodermal dysplasias seen in human Ellis-van Creveld and Sensenbrenner's syndromes, suggests an unappreciated role for primary cilia in the skin and hair follicle
Cellulosomics, a gene-centric approach to investigating the intraspecific diversity and adaptation of Ruminococcus flavefaciens within the rumen
Peer reviewedPublisher PD
- âŠ