Quantum Hamiltonian Reduction of the Schwinger Model

We reexamine a unitary-transformation method of extracting a physical Hamiltonian from a gauge field theory after quantizing all degrees of freedom including redundant variables. We show that this {\it quantum Hamiltonian reduction} method suffers from crucial modifications arising from regularization of composite operators. We assess the effects of regularization in the simplest gauge field theory, the Schwinger model. Without regularization, the quantum reduction yields the identical Hamiltonian with the classically reduced one. On the other hand, with regularization incorporated, the resulting Hamiltonian of the quantum reduction disagrees with that of the classical reduction. However, we find that the discrepancy is resolved by redefinitions of fermion currents and that the results are again consistent with those of the classical reduction.Comment: 23 pages, LaTeX file, UT-Komaba 94-

Rofecoxib and cardiovascular adverse events in adjuvant treatment of colorectal cancer

Background Selective cyclooxygenase inhibitors may retard the progression of cancer, but they have enhanced thrombotic potential. We report on cardiovascular adverse events in patients receiving rofecoxib to reduce rates of recurrence of colorectal cancer. Methods All serious adverse events that were cardiovascular thrombotic events were reviewed in 2434 patients with stage II or III colorectal cancer participating in a randomized, placebo-controlled trial of rofecoxib, 25 mg daily, started after potentially curative tumor resection and chemotherapy or radiotherapy as indicated. The trial was terminated prematurely owing to worldwide withdrawal of rofecoxib. To examine possible persistent risks, we examined cardiovascular thrombotic events reported up to 24 months after the trial was closed. Results The median duration of active treatment was 7.4 months. The 1167 patients receiving rofecoxib and the 1160 patients receiving placebo were well matched, with a median follow-up period of 33.0 months (interquartile range, 27.6 to 40.1) and 33.4 months (27.7 to 40.4), respectively. Of the 23 confirmed cardiovascular thrombotic events, 16 occurred in the rofecoxib group during or within 14 days after the treatment period, with an estimated relative risk of 2.66 (from the Cox proportional-hazards model; 95% confidence interval [CI], 1.03 to 6.86; P = 0.04). Analysis of the Antiplatelet Trialists’ Collaboration end point (the combined incidence of death from cardiovascular, hemorrhagic, and unknown causes; of nonfatal myocardial infarction; and of nonfatal ischemic and hemorrhagic stroke) gave an unadjusted relative risk of 1.60 (95% CI, 0.57 to 4.51; P = 0.37). Fourteen more cardiovascular thrombotic events, six in the rofecoxib group, were reported within the 2 years after trial closure, with an overall unadjusted relative risk of 1.50 (95% CI, 0.76 to 2.94; P = 0.24). Four patients in the rofecoxib group and two in the placebo group died from thrombotic causes during or within 14 days after the treatment period, and during the follow-up period, one patient in the rofecoxib group and five patients in the placebo group died from cardiovascular causes. Conclusions Rofecoxib therapy was associated with an increased frequency of adverse cardiovascular events among patients with a median study treatment of 7.4 months’ duration. (Current Controlled Trials number, ISRCTN98278138.

ALLN-177, oral enzyme therapy for hyperoxaluria

PURPOSE: To evaluate the potential of ALLN-177, an orally administered, oxalate-specific enzyme therapy to reduce urine oxalate (UOx) excretion in patients with secondary hyperoxaluria. METHODS: Sixteen male and female subjects with both hyperoxaluria and a kidney stone history were enrolled in an open-label study. Subjects continued their usual diets and therapies. During a 3-day baseline period, two 24-h (24-h) urines were collected, followed by a 4-day treatment period with ALLN-177 (7,500 units/meal, 3 × day) when three 24-h urines were collected. The primary endpoint was the change in mean 24-h UOx from baseline. Safety assessments and 24-h dietary recalls were performed throughout. RESULTS: The study enrolled 5 subjects with enteric hyperoxaluria and 11 with idiopathic hyperoxaluria. ALLN-177 was well tolerated. Overall mean (SD) UOx decreased from 77.7 (55.9) at baseline to 63.7 (40.1) mg/24 h while on ALLN-177 therapy, with the mean reduction of 14 mg/24 h, (95% CI - 23.71, - 4.13). The calcium oxalate-relative urinary supersaturation ratio in the overall population decreased from a mean of 11.3 (5.7) to 8.8 (3.8) (- 2.8; 95% CI - 4.9, - 0.79). This difference was driven by oxalate reduction alone, but not any other urinary parameters. Mean daily dietary oxalate, calcium, and fluid intake recorded by frequent diet recall did not differ by study periods. CONCLUSION: ALLN-177 reduced 24-h UOx excretion, and was well tolerated. The results of this pilot study provided justification for further investigation of ALLN-177 in patients with secondary hyperoxaluria

A titanium-nitride near-infrared kinetic inductance photon-counting detector and its anomalous electrodynamics

We demonstrate single-photon counting at 1550 nm with titanium-nitride (TiN) microwave kinetic inductance detectors. Energy resolution of 0.4 eV and arrival-time resolution of 1.2 microseconds are achieved. 0-, 1-, 2-photon events are resolved and shown to follow Poisson statistics. We find that the temperature-dependent frequency shift deviates from the Mattis-Bardeen theory, and the dissipation response shows a shorter decay time than the frequency response at low temperatures. We suggest that the observed anomalous electrodynamics may be related to quasiparticle traps or subgap states in the disordered TiN films. Finally, the electron density-of-states is derived from the pulse response.Comment: 4 pages, 3 figure

Parathyroid hormone-stimulated calcium absorption in cTAL from vitamin D-deficient rabbits

Parathyroid hormone-stimulated calcium absorption in cTAL from vitamin D-deficient rabbits. Cortical thick ascending limbs of Henle's loop were dissected from the kidneys of chronically vitamin D-deficient or -replete rabbits and perfused in vitro. Unidirectional transepithelial calcium fluxes from lumen to bath were measured with 45Ca. The tubules were bathed in a solution containing 150mM sodium and perfused with a solution containing 60mM sodium to simulate conditions in the cortical thick ascending limb in vivo. Transepithelial voltages were equal across tubules from vitamin D-deficient and -replete rabbits. Likewise, baseline and parathyroid hormone-stimulated calcium fluxes were the same in tubules from the two groups. Because calcidiol and calcitriol were undetectable in the serum of the vitamin D-deficient rabbits, we suggest that neither of these endogenous vitamin D metabolites is essential in the regulation of calcium absorption in this portion of the rabbit nephron

STEAP4 expression in human islets is associated with differences in body mass index, sex, HbA1c, and inflammation

Objective STEAP4 (six-transmembrane epithelial antigen of the prostate 4) is a metalloreductase that has been shown previously to protect cells from inflammatory damage. Genetic variants in STEAP4 have been associated with numerous metabolic disorders related to obesity, including putative defects in the acute insulin response to glucose in type 2 diabetes. Purpose We examined whether obesity and/or type 2 diabetes altered STEAP4 expression in human pancreatic islets. Methods Human islets were isolated from deceased donors at two medical centers and processed for quantitative polymerase chain reaction. Organ donors were selected by status as non-diabetic or having type 2 diabetes. Site 1 (Edmonton): N = 13 type 2 diabetes donors (7M, 6F), N = 20 non-diabetic donors (7M, 13F). Site 2 (Virginia): N = 6 type 2 diabetes donors (6F), N = 6 non-diabetic donors (3M, 3F). Results STEAP4 showed reduced islet expression with increasing body mass index among all donors (P < 0.10) and non-diabetic donors (P < 0.05) from Site 1; STEAP4 showed reduced islet expression among type 2 diabetes donors with increasing hemoglobin A1c. Islet STEAP4 expression was also marginally higher in female donors (P < 0.10). Among type 2 diabetes donors from Site 2, islet insulin expression was reduced, STEAP4 expression was increased, and white blood cell counts were increased compared to non-diabetic donors. Islets from non-diabetic donors that were exposed overnight to 5 ng/ml IL-1β displayed increased STEAP4 expression, consistent with STEAP4 upregulation by inflammatory signaling. Conclusions These findings suggest that increased STEAP4 mRNA expression is associated with inflammatory stimuli, whereas lower STEAP4 expression is associated with obesity in human islets. Given its putative protective role, downregulation of STEAP4 by chronic obesity suggests a mechanism for reduced islet protection against cellular damage

Monopoles and Knots in Skyrme Theory

We show that the Skyrme theory actually is a theory of monopoles which allows a new type of solitons, the topological knots made of monopole-anti-monopole pair,which is different from the well-known skyrmions. Furthermore, we derive a generalized Skyrme action from the Yang-Mills action of QCD, which we propose to be an effective action of QCD in the infra-red limit. We discuss the physical implications of our results.Comment: 4 pages. Phys. Rev. Lett. in pres

Producción de vaquillonas pesadas en condiciones de pastoreo y su impacto en la terneza de la carne

Históricamente, en el mercado argentino la vaquillona de más de 320 kg de peso vivo (PV) ha sido incluida en la categoría de “vacas”, lo cual disminuye sensiblemente el precio que el productor obtenía por ese animal. Dado que dentro de un amplio rango de edades la terneza se encuentra negativamente asociada con la edad del animal, esta modalidad de comercialización se habría implementado para evitar comercializar vacas como vaquillonas. Sin embargo, Shackelford et al. (1995) concluyen que la magnitud de la diferencias de terneza en el músculo longissimus encontradas entre vaquillonas (15-18 meses de edad) y vacas de dos años de edad difí- cilmente justifiquen un menor valor de mercado de las últimas respecto a las vaquillonas. En Argentina, a partir de diciembre de 2005 entró en vigencia la disposición de la Oficina de Nacional de Control Comercial Agropecuario (ONCCA) 5701/2005, a través de la cual se crearon distintas categorías de peso vivo de vaquillonas especiales y buenas (300 a 340, 341 a 380, y 381 a 420 kg PV), y una categoría de vaquillonas regulares. Esta nueva categorización permitiría diferenciar las vaquillonas de las vacas. Sin embargo, las vaquillonas de más de 320 kg PV siguieron siendo penalizadas en el mercado con un menor precio. Según la base de datos del Mercado de Liniers S.A. (http://www.mercado deliniers.com.ar/), el precio medio durante el año 2006 en ese Mercado para las vaquillonas de 300 a 340 kg PV fue de $2.50 por kg PV y para las de 381 a 420 kg PV de$2,17. Esta reducción en el precio de vaquillonas por aumento de peso fue 80% mayor que en los novillitos por similar cambio de peso ($2,60 a$2,46 por kg). Esto se reflejó en que durante el 2006, sólo el 6% del total de vaquillonas comercializadas correspondió a vaquillonas pesadas, mientras que los novillitos pesados representaron el 27% del total de novillitos. En la literatura hay evidencias que indican que las diferencias en terneza generadas por variaciones en la edad o por el sexo no justificarían tales desviaciones en los precios. En un sistema de producción pastoril con una ganancia diaria de peso vivo media de 500 g, producir una vaquillona pesada en vez de una liviana demandaría aproximadamente 5 meses más. Si bien Wulf et al. (1996) observaron que lag fuerza de corte (dureza) de distintos cortes de carne de novillos en el rango de 15 a 18 meses de edad terminados en dietas a base de concentrados se correlacionaba positivamente con la edad, el coeficiente de correlación fue relativamente bajo (r=0.18). Sin embargo, dado que en este trabajo los animales fueron faenados a medida que alcanzaban los 400 kg de peso vivo o 1 cm de espesor de grasa dorsal, habría un efecto confundido de la edad y la tasa de ganancia de peso sobre la terneza (Perry and Thompson, 2005). Por otra parte, Field et al. (1996) no observaron diferencias en la terneza del músculo longissimus dorsi de vaquillonas faenadas a 31, 33 y 35 meses de edad luego de 100 d de alimentación con concentrados. Lawrence et al. (2001) al evaluar el efecto de la edad (determinada por el número de incisivos permanentes: 0, 2, 4, 6, y 8), el sexo (vaquillonas vs. novillos) y su interacción sobre la terneza del músculo longissimus dorsi tampoco encontraron diferencias significativas. Si bien en el trabajo de Zinn et al., (1970) el sexo (vaquillonas vs. novillos) no afectó la terneza de tres músculos (Triceps brachii, longissimus dorsi y Semimenbranosus) de animales terminados con dietas concentradas, Choat et al. (2006) reportan que, con 7 d de maduración, la terneza del músculo longissimus dorsi fue menor en vaquillonas que en novillos. Sin embargo, dicha diferencia desapareció al incrementar el tiempo de maduración de la carne. El presente trabajo busca definir elementos biológicos que ayuden a establecer el valor de la carne producida de forma más objetiva. Así el primer objetivo del presente trabajo fue el de comparar la fuerza de corte (terneza) de los músculos longissimus y gluteus medius de vaquillonas pesadas con la de los mismos músculos de vaquillonas livianas, novillitos pesados, o vacas de refugo. El segundo objetivo fue el de determinar si posibles diferencias en la fuerza de corte del producto obtenido con las distintas categorías o con distintos músculos pueden ser eliminadas con un mayor tiempo de maduración.Fil: Lucero Borja, J. Universidad Nacional de Mar del Plata; ArgentinaFil: Pouzo, Laura Beatriz. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Langman, L.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; ArgentinaFil: Carduza, F.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; ArgentinaFil: Corva, P.. Universidad Nacional de Mar del Plata; ArgentinaFil: Santini, Francisco Jose. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pavan, E.. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Risk factors for squamous cell carcinoma of the oesophagus in women: a case–control study

Oesophageal cancer rates in women in the UK are more than 3 times higher than in most other European populations. A population-based matched case–control study of histologically confirmed squamous cell carcinoma of the oesophagus in women was carried out in 4 regions in England and Scotland. Interviews were carried out in hospital or at home and topics included: smoking; alcohol; tea and coffee consumption; medical and obstetric history; and diet. Response rates were 62% for cases and 65% for first-chosen controls. There were 159 case–control pairs. Significant results were found for: eating salads (odds ratio (OR) 0.42, 95% CI 0.20–0.92 in the highest quartile of consumption) and a light (as distinct from no) breakfast (OR 0.18, 95% CI 0.07 – 0.48) were protective; quantity of tea was a risk factor and there was a significant positive trend with temperature at which hot drinks were consumed (P = 0.03). Alcohol consumption was unrelated to risk, but there was a significant trend with years of smoking (P = 0.015). A protective effect of aspirin consumption was confined to the English centres (OR 0.08, 95% CI 0.01–0.56). Comparison with a parallel study of adenocarcinoma indicated a common protective effect of a healthy diet but otherwise distinct risk factors. © 2001 Cancer Research Campaign http://www.bjcancer.co