Quantizations on the circle and coherent states

We present a possible construction of coherent states on the unit circle as configuration space. Our approach is based on Borel quantizations on S^1 including the Aharonov-Bohm type quantum description. The coherent states are constructed by Perelomov's method as group related coherent states generated by Weyl operators on the quantum phase space Z x S^1. Because of the duality of canonical coordinates and momenta, i.e. the angular variable and the integers, this formulation can also be interpreted as coherent states over an infinite periodic chain. For the construction we use the analogy with our quantization and coherent states over a finite periodic chain where the quantum phase space was Z_M x Z_M. The coherent states constructed in this work are shown to satisfy the resolution of unity. To compare them with canonical coherent states, also some of their further properties are studied demonstrating similarities as well as substantial differences.Comment: 15 pages, 4 figures, accepted in J. Phys. A: Math. Theor. 45 (2012) for the Special issue on coherent states: mathematical and physical aspect

Risk Factors for Hospital Malpractice Exposure: Implications for Managers and Insurers

The possibility of identifying certain variables that might serve as predictors of above- or below-average medical malpractice claims experience was explored. Results showed that it is possible to identify significant risk factors

Natural mortality of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) eggs in Argentina and Italy, and first record of Encarsia porteri (Mercet) (Hymenoptera: Aphelinidae) affecting its populations

En este estudio se evaluaron los agentes oófagos de T. absoluta de presencia espontánea en cultivos de tomate en Sudamérica (NOA y Cinturón Hortícola Platense, Argentina) y en Europa (Lazio, Italia). Se reporta el listado de especies encontradas y las tasas de mortalidad natural por parasitismo y depredación en cultivos de ambos continentes. Además, se informa el primer registro de Encarsia porteri (Mercet) (Hymenoptera: Aphelinidae) parasitando huevos de la polilla.Oophagous biological control agents of T. absoluta naturally present in crops in South America (Buenos Aires and Tucumán Provinces, Argentina) and Europe (Lazio, Italia) were surveyed. A taxonomic list of species and the natural mortality rates caused by parasitism and predation are reported. Furthermore, the first record of Encarsia porteri (Mercet) (Hymenoptera: Aphelinidae) parasitizing T. absoluta eggs is informed.Fil: Luft, Érica. San Miguel de Tucumán (Tucumán, Argentina). CONICET - Planta Piloto de Procesos Industriales Microbiológicos-Biotecnología, Div. Control Biológico.Fil: Luna, María Gabriela. Universidad Nacional de La PlataFil: Galise, Gabriele. Italia. Università degli Studi della Tuscia.Fil: Speranza, Stefano. Italia. Università degli Studi della Tuscia.Fil: Virla, Eduardo G.. San Miguel de Tucumán (Tucumán, Argentina). CONICET - Planta Piloto de Procesos Industriales Microbiológicos-Biotecnología, Div. Control Biológico

Coherent states on the circle

We present a possible construction of coherent states on the unit circle as configuration space. In our approach the phase space is the product Z x S^1. Because of the duality of canonical coordinates and momenta, i.e. the angular variable and the integers, this formulation can also be interpreted as coherent states over an infinite periodic chain. For the construction we use the analogy with our quantization over a finite periodic chain where the phase space was Z_M x Z_M. Properties of the coherent states constructed in this way are studied and the coherent states are shown to satisfy the resolution of unity.Comment: 7 pages, presented at GROUP28 - "28th International Colloquium on Group Theoretical Methods in Physics", Newcastle upon Tyne, July 2010. Accepted in Journal of Physics Conference Serie

Dihedral symmetry of periodic chain: quantization and coherent states

Our previous work on quantum kinematics and coherent states over finite configuration spaces is extended: the configuration space is, as before, the cyclic group Z_n of arbitrary order n=2,3,..., but a larger group - the non-Abelian dihedral group D_n - is taken as its symmetry group. The corresponding group related coherent states are constructed and their overcompleteness proved. Our approach based on geometric symmetry can be used as a kinematic framework for matrix methods in quantum chemistry of ring molecules.Comment: 13 pages; minor changes of the tex

Monitoring and Pay: An Experiment on Employee Performance under Endogenous Supervision

We present an experimental test of a shirking model where monitoring intensity is endogenous and effort a continuous variable. Wage level, monitoring intensity and consequently the desired enforceable effort level are jointly determined by the maximization problem of the firm. As a result, monitoring and pay should be complements. In our experiment, between and within treatment variation is qualitatively in line with the normative predictions of the model under standard assumptions. Yet, we also find evidence for reciprocal behavior. Our data analysis shows, however, that it does not pay for the employer to solely rely on the reciprocity of employees

No Impact of Body Mass Index on Outcome in Stroke Patients Treated with IV Thrombolysis BMI and IV Thrombolysis Outcome.

The impact of excess body weight on prognosis after stroke is controversial. Many studies report higher survival rates in obese patients ("obesity paradox"). Recently, obesity has been linked to worse outcomes after intravenous (IV) thrombolysis, but the number and sample size of these studies were small. Here, we aimed to assess the relationship between body weight and stroke outcome after IV thrombolysis in a large cohort study. In a prospective observational multicenter study, we analyzed baseline and outcome data of 896 ischemic stroke patients who underwent IV thrombolysis. Patients were categorized according to body mass index (BMI) as underweight (<18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), obese (30-34.9 kg/m2) or severely obese (>35 kg/m2). Using uni- and multivariate modeling, we assessed the relationship of BMI with favorable outcome (defined as modified Rankin Scale 0 or 1) and mortality 3 months after stroke as well as the occurrence of symptomatic intracerebral hemorrhages (sICH). We also measured the incidence of patients that had an early neurological improvement of >40% on the National Institutes of Health Stroke Scale (NIHSS) after 24 hours. Among 896 patients, 321 were normal weight (35.8%), 22 underweight (2.5%), 378 overweight (42.2%), 123 obese (13.7%) and 52 severely obese (5.8%). Three-month mortality was comparable in obese vs. non-obese patients (8.1% vs. 8.3%) and did not differ significantly among different BMI groups. This was also true for favorable clinical outcome, risk of sICH and early neurological improvement on NIHSS at 24 hours. These results remained unchanged after adjusting for potential confounding factors in the multivariate analyses. BMI was not related to clinical outcomes in stroke patients treated with IVT. Our data suggest that the current weight-adapted dosage scheme of IV alteplase is appropriate for different body weight groups, and challenge the existence of the obesity paradox after stroke

The changing nature of risk and risk management: the challenge of borders, uncertainty and resilience

No abstract available