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The general linear group as a complete invariant for C*-algebras
In 1955 Dye proved that two von Neumann factors not of type I_2n are
isomorphic (via a linear or a conjugate linear *-isomorphism) if and only if
their unitary groups are isomorphic as abstract groups. We consider an analogue
for C*-algebras. We show that the topological general linear group is a
classifying invariant for simple, unital AH-algebras of slow dimension growth
and of real rank zero, and the abstract general linear group is a classifying
invariant for unital Kirchberg algebras in the UCT class.Comment: 23 page
Purely infinite partial crossed products
Let (A,G,\alpha) be a partial dynamical system. We show that there is a
bijective correspondence between G-invariant ideals of A and ideals in the
partial crossed product A xr G provided the action is exact and residually
topologically free. Assuming, in addition, a technical condition---automatic
when A is abelian---we show that A xr G is purely infinite if and only if the
positive nonzero elements in A are properly infinite in A xr G. As an
application we verify pure infiniteness of various partial crossed products,
including realisations of the Cuntz algebras O_n, O_A, O_N, and O_Z as partial
crossed products.Comment: 30 page
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Systemic and Intra-Habenular Activation of the Orphan G Protein-Coupled Receptor GPR139 Decreases Compulsive-Like Alcohol Drinking and Hyperalgesia in Alcohol-Dependent Rats.
GPR139 is an orphan G protein-coupled receptor (GPCR) that is expressed mainly in the brain, with the highest expression in the medial habenula. The modulation of GPR139 receptor function has been hypothesized to be beneficial in the treatment of some mental disorders, but behavioral studies have not yet provided causal evidence of the role of GPR139 in brain dysfunction. Because of the high expression of GPR139 in the habenula, a critical brain region in addiction, we hypothesized that GPR139 may play role in alcohol dependence. Thus, we tested the effect of GPR139 receptor activation using the selective, brain-penetrant receptor agonist JNJ-63533054 on addiction-like behaviors in alcohol-dependent male rats. Systemic administration of JNJ-63533054 (30 mg/kg but not 10 mg/kg, p.o.) reversed the escalation of alcohol self-administration in alcohol-dependent rats, without affecting water or saccharin intake in dependent rats or alcohol intake in nondependent rats. Moreover, systemic JNJ-63533054 administration decreased withdrawal-induced hyperalgesia, without affecting somatic signs of alcohol withdrawal. Further analysis demonstrated that JNJ-63533054 was effective only in a subgroup of dependent rats that exhibited compulsive-like alcohol drinking. Finally, site-specific microinjection of JNJ-63533054 in the habenula but not interpeduncular nucleus (IPN) reduced both alcohol self-administration and withdrawal-induced hyperalgesia in dependent rats. These results provide robust preclinical evidence that GPR139 receptor activation reverses key addiction-like behaviors in dependent animals, suggest that GPR139 may be a novel target for the treatment of alcohol use disorder, and demonstrate that GPR139 is functionally relevant in regulating mammalian behavior
USAGE AND ACCEPTABIITY OF DATA NORMALIZATION IN BASEBALL PITCHING
To account for athletes of different sizes, kinetic values are commonly ‘normalized’ by dividing by mass and/or height. However, the creation of a ratio variable requires certain statistical assumptions to be met. The purpose of this study was to determine if elbow valgus torque predicted by pitching velocity is influenced by the normalization method using regression model comparison with normalized torque values. Both mass and mass*height normalization satisfied the correlation and zero intercept assumptions. Results did not agree between analysis methods that elbow valgus torque could be predicted with pitching velocity at the α = 0.05 level, indicating caution should be exercised before normalizing pitching kinetics data without confirming the assumptions for a ratio variable are met
Unreinforced and TRM-reinforced masonry building subjected to pseudo-dynamic excitations: numerical and experimental insights
[EN] This paper contains a numerical study based on tests carried out at the Universitat Politècnica de València (Spain) on a U-shaped unreinforced and TRM-reinforced masonry building structure subjected to horizontal loads. The masonry was composed of clay bricks with 10 mm thick mortar joints arranged in an English bond manner. The prototype was tested by applying pseudo-dynamic displacement-driven cycles and varying cyclic amplitudes and frequencies in two different stages: (i) on the as-built structure and (ii) after the repair and the application of Textile Reinforced Mortar (TRM) material. A series of non-linear numerical simulations were performed adopting the ABAQUS/Explicit FE software. The FE calibration was carried out using the results obtained during ambient vibration tests. Simulations were then used to evaluate the effectiveness of the proposed TRM technique to increasing the strength of low-rise old masonry building structures.The authors would like to express their gratitude to the Spanish Ministry of Economy, Industry and Competitiveness for the funding provided (BIA 2014-59036-R-AR), and also to the Grupo Mapei and Grupo Puma for their invaluable assistance during the experimental tests.Giordano, E.; Bertolesi, E.; Clementi, F.; Buitrago, M.; Adam, JM.; Ivorra Chorro, S. (2021). Unreinforced and TRM-reinforced masonry building subjected to pseudo-dynamic excitations: numerical and experimental insights. Journal of Engineering Mechanics. 147(12):04021107-1-04021107-15. https://doi.org/10.1061/(ASCE)EM.1943-7889.0002017S04021107-104021107-151471
THE RELATIONSHIP BETWEEN TRUNK ENERGY FLOW AND COLLEGIATE SOFTBALL HITTING PERFORMANCE
The purpose of this study was to determine the relationship between trunk energy flow and performance (exit velocity) during collegiate softball hitting. Nineteen collegiate softball athletes (age: 19.6 ± 1.0yrs) performed three maximal effort swings off a pitching machine. Kinematic data were collected using an electromagnetic tracking system. A segmental power analysis was performed to quantify peak rates of trunk energy flow (proximal inflow (IF) and distal outflow (OF) on front and back sides). Regression analyses determined exit velocity was best predicted by peak rate of distal trunk energy OF on the front side. On average, the model showed exit velocity increased by .9 mph for every 100 W increase in distal trunk energy OF on the front side while holding body mass constant
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