Combinatorial classification of quantum lens spaces

We answer the question of how large the dimension of a quantum lens space must be, compared to the primary parameter $r$, for the isomorphism class to depend on the secondary parameters. Since classification results in C*-algebra theory reduces this question to one concerning a certain kind of $SL$-equivalence of integer matrices of a special form, our approach is entirely combinatorial and based on the counting of certain paths in the graphs shown by Hong and Szyma\'nski to describe the quantum lens spaces.Comment: 27 pages, 2 figure

Examining Perceptions about Restorative Justice Among Correctional Managers and Leaders

There has been an increasing dissatisfaction with the current criminal justice system, and restorative justice with its ancient roots, has made its way into criminal justice in the past 20 years as a different way of thinking about crime. The Minnesota Department of Corrections established a Restorative Justice unit in 1994 as the first state in the nation. To adapt restorative justice in the prison system, a change in organizational culture is required, and it is important that managers and leaders understand and accept the principles. A questionnaire with closed and open-ended questions was sent to managers and leaders in three prisons in Minnesota. The purpose was to gather information about correctional managers\u27 and leaders\u27 perceptions of own knowledge, and acceptance of restorative justice; what barriers they view against change; and to asses to what degree they believe restorative justice is an appropriate future direction for the Department of Corrections. Findings indicated that the majority of managers and leaders understand the basic values and principles, and many believe it is an appropriate future direction. Other indications were that staff training is an important strategy for change, and that lack of funding, work-load and lack of knowledge among staff are barriers to change

A dual action coumarin-camptothecin polymer for light responsive drug release and photodynamic therapy.

A light-responsive polymer allowing the controlled release of camptothecin and the generation of reactive oxygen species (ROS) is reported. The polymer was prepared by controlled copolymerisation of water-soluble N,N-dimethyl acrylamide with a bromocoumarin methacrylate monomer. The lipophilic chemotherapy agent camptothecin was caged onto the coumarin unit via a photo-cleavable carbonate ester enabling light-triggered cargo release. The polymer showed good biocompatibility in the dark, and high cancer cell killing activity mediated both by the photo-release of camptothecin and ROS generation

Are we going to stand by and let these children come into the world? : the impact of the Thalidomide disaster in South Africa, 1960-1977

Thalidomide is in many ways the archetypal drug of our era. Produced in the mid-1950s by German firm Chemie-Grünenthal GmbH, and sold directly by them or by licencees, it was one of a multitude of medications industrially created during the post-war boom in synthetic drugs and aggressively marketed for multiple uses on a global scale. Most notoriously given to pregnant women suffering from morning sickness, without adequate testing for either toxicity or effectiveness, thalidomide was advertised as being ‘completely non-poisonous, completely safe’. Instead, in what became known as the ‘thalidomide scandal’, it caused malformations resulting in at least 10,000 children being born with severe disabilities. Previous research has shown that thalidomide was given out as samples, sold over the counter, or distributed via national health ..

Fluorophore-Tagged Poly-Lysine RAFT Agents: Controlled Synthesis of Trackable Cell-Penetrating Peptide-Polymers.

The conjugation of a fluorophore and a variety of cell-penetrating peptides onto a RAFT agent allowed for the synthesis of polymers of defined sizes with quantifiable cell-uptake. Each peptide-RAFT agent was used to polymerize acrylamide, acrylate, and styrene monomers to form high or low molecular weight polymers (here 50 or 7.5 kDa) with the peptide having no influence on the RAFT agent's control. The incorporation of a single fluorophore per polymer chain allowed cellular analysis of the uptake of the size-specific peptide-polymers via flow cytometry and confocal microscopy. The cell-penetrating peptides had a direct effect on the efficiency of polymer uptake for both high and low molecular weight polymers, demonstrating the versatility of the strategy. These "all-in-one", synthetically accessible RAFT agents allow highly controlled preparation of synthetic peptide-polymer conjugates and subsequent quantification of their delivery into cells

Interdependence of magnetism and superconductivity in the borocarbide TmNi2B2C

We have discovered a new antiferromagnetic phase in TmNi2B2C by neutron diffraction. The ordering vector is Q_A = (0.48,0,0) and the phase appears above a critical in-plane magnetic field of 0.9 T. The field was applied in order to test the assumption that the zero-field magnetic structure at Q_F = (0.094,0.094,0) would change into a c-axis ferromagnet if superconductivity were destroyed. We present theoretical calculations which show that two effects are important: A suppression of the ferromagnetic component of the RKKY exchange interaction in the superconducting phase, and a reduction of the superconducting condensation energy due to the periodic modulation of the moments at the wave vector Q_A

KINETICS AND ELECTROMYOGRAPHY OF THE MARTIAL ARTS HIGH FRONT KICK

INTRODUCTION Fast unloaded movements like striking, throwing and kicking are typically performed in a proximo-distal sequence: Initially proximal segments accelerate while distal segments lag behind, then proximal segments deceler- ate while distal segments accelerate. In kicking, for instance, it is observed that the movement starts with forward angular acceleration of the thigh while the shank lags behind. Then the thigh decelerates while simultaneously the shank accelerates and the foot reaches its maximal velocity. This raises two questions: Is the thigh actively decelerated by the glutei and/or hamstring muscles, or passively decelerated by joint reaction forces from the accelerating shank7 Is acceleration of the shank enhanced by the thigh's deceleration? From a kinematic perspective this movement coordination seems disadvantageous, considering that the resulting linear velocity of the foot relative to the ground equals the vector sum of the resulting linear velocity of the knee relative to the ground and the foot relative to the knee. However, from a kinetic perspective it can be argued that thigh deceleration enhances shah acceleration to a degree where toss of knee velocity is more than accounted for in gain of foot velocity. The theory is that the angularly decelerating thigh exerts a knee joint force which causes angular acceleration of the shank, i.e. a %hip-lash" action. To obtain knowledge regarding how these kinds of movements are performed we decided to examine the martial arts high front kick. Similar to previous kicking studies we did so by kinematic measurements but in addition recorded the electrical activity of selected muscles in order to asses their temporal activation during the kick. METHODS Seventeen skilled taekwondo practitioners (14 males. 3 females) volunteered to take part in this study. Each subject performed three high front kicks aiming at a tennis ball suspended from the ceiling and adjusted to chin level. The fastest kick from each subject was selected for further analysis. The subjects were high speed filmed (200 f.p.s.) from their right side while kicking. Contrasting markers on selected anatomical landmarks enabled subsequent automatic digitisation. Displacement data were lowpass filtered with optimal cut-off frequencies (6-1 0 Hz) determined by use of residual analysis/ Jackson Knee method. Velocities and accelerations were derived from the displacement data by finite difference calculation. During kicking the electtomyographic activity (EMG) from five selected leg muscles were measured with surface electrodes. Kinetic data were obtained through inverse dynamics calculation using a two-segment link-segment model of the kicking leg and the movement equations developed by Putnam (1983). These equations enable division of the resulting moment acting on a segment into muscular components and motion de- pendant components arising from movement of adjacent segments. RESULTS Data for the thigh indicated that deceleration was caused by motion dependant moments arising from shank motion and not by active hip extensor muscles. Shank acceleration was caused partly by a knee extensor muscle moment and partly by a motion dependant moment arising from thigh angular velocity. Both thigh and shank kinetics were supported by EMG recordings. CONCLUSION As part of the accelerating moment acting on the shank was due to thigh angular velocity we suggest that the observed thigh deceleration should be considered unwanted but unavoidable due to shank acceleration. This implies that even though knee extensor muscles are important for shank acceleration the hip flexor muscles must not be neglected

JUMPING STRATEGIES IN A VOLLEYBALL AND A BALLET SPECIFIC JUMP

INTRODUCTION The performance of a maximal vertical jump fram a static preparatory position (SQJ) or starting with a counter movement (CMJ) implies transformation of rotation about the hip, knee and ankle joints to a maximal translatory movement. Different strategies have been proposed for this transformation. Previously both sequential and simullaneous strategies have been proposed as optimal for maximal vertical jumping (1 & 2). The purpose of this study was to analyze ]umping strategies in a sport and dance specific maximal vertical jump. The hypothesis was that the technical demands of the Jumps would preset the strategy. Six male subjects participated in the study three professional ballet dancers and three elite volleyball players. In the ballet specific jump (BSJ) the legs were outward rotated, one foot was placed in front of and close to the other foot and the upper body kept upright. Three elite volleyball players performed the jump used for the smash (VSJ) including a three step preliminary run up and a farcefull arm swing. Afterwards all six subjects performed SQJ and CMJ. The ]umps were recorded on high speed film (500Hz) combined with registrations trom an AMTI force platform and EMG recordings from the major lower extremity muscles Net joint moments and joint work ware calculated by inverse dynamics. The strategy of the jumps was determined on the basis of angular kinematics and the pattern of nel joint moments of the two dominant joints RESULTS For BSJ the jumping height (h) was 0.22O.28m.The war!< contribution from the knee and ankle joint were 50-70% and 47-63% of the total work respectively while the work at the hip joint showed a negative contribution of 13-17% caused by a net hip flexor moment. Because of the specific ballet position the hip extension took place in the frontal plane and mgluteus maximus could not contribute to the extension. The concentric activity in mrectus femoris could partly explain the hip flexor moment. The knee and ankle joint initiated the extension phase simultaneously and the net joint moments peaked also simultaneously Therefore, the strategy could be defined as simultaneous. For VSJ h was 0.310.45m. The work contribution fram the knee and hip joints were 22-60% and 35-62% of the total work respectively. The hip joint began the extension phase before the body center of mass had reached its lowest position (sn The knee extension began 40-100ms after s.j. The peaks of the net joint moments of the hip and knee showed a similar pattern. Accordingly, the strategy could be defined as sequentiaL The sequential joint extension could partly be explained by the forcefull armswing pressing down and giving negative momentum in the downward phase and by this delaying the knee extension. In SQJ and CMJ h was 0.22-0.36m and 0.33-0AOm. The work contribution from the knee was 64.5%(SE 5.9) and 76.0% (SE 9.2) and from the hip 18.8% (SE 5.8) and 133% (SE 8.7). One ballet dancer and one volleyball player performed SQJ and CMJ with a simultaneous strategy while the otller four subjects used a sequential strategy. CONCLUSION In a maximal vertical jump fram ballet and from volleyball the technical demands preset the jumping strategy. When the subjects were asked to perform SQJ and CMJ the choice of strategy seemed individual and not connected to the training background. REFERENCES (1) Hudson, J.L. (1986). Med Sci. Sports Exerc, 18,242-251 (2) Babbert, M.F. & van lngen Schenau, G.J. (1986). J Biomechanics, 21, 249•26

Bose-Einstein Condensation in a CO_2-laser Optical Dipole Trap

We report on the achieving of Bose-Einstein condensation of a dilute atomic gas based on trapping atoms in tightly confining CO_2-laser dipole potentials. Quantum degeneracy of rubidium atoms is reached by direct evaporative cooling in both crossed and single beam trapping geometries. At the heart of these all-optical condensation experiments is the ability to obtain high initial atomic densities in quasistatic dipole traps by laser cooling techniques. Finally, we demonstrate the formation of a condensate in a field insensitive m_F=0 spin projection only. This suppresses fluctuations of the chemical potential from stray magnetic fields.Comment: 8 pages, 5 figure