A semiclassical model of light mesons

The dominantly orbital state description is applied to the study of light mesons. The effective Hamiltonian is characterized by a relativistic kinematics supplemented by the usual funnel potential with a mixed scalar and vector confinement. The influence of two different finite quark masses and potential parameters on Regge and vibrational trajectories is discussed.Comment: 1 figur

Filling and wetting transitions of nematic liquid crystals on sinusoidal substrates

Close to sinusoidal substrates, simple fluids may undergo a filling transition, in which the fluid passes from a dry to a filled state, where the interface remains unbent but bound to the substrate. Increasing the surface field, the interface unbinds and a wetting transition occurs. We show that this double-transition sequence may be strongly modified in the case of ordered fluids, such as nematic liquid crystals. Depending on the preferred orientation of the nematic molecules at the structured substrate and at the isotropic-nematic interface, the filling transition may not exist, and the fluid passes directly from a dry to a complete-wet state, with the interface far from the substrate. More interestingly, in other situations, the complete wetting transition may be prevented, and the fluid passes from a dry to a filled state, and remains in this configuration, with the interface always attached to the substrate, even for very large surface fields. Both transitions are only observed for a same substrate in a narrow range of amplitudes

H1N1 disseminated infection in a 3-month-old boy

Earlier this year a new influenza virus emerged. In children, the clinical manifestations of H1N1 infection are similar to those reported during periods of seasonal influenza. We report on a 3-month-old boy with an upper respiratory tract infection who presented enteropathy, coagulopathy and encephalitis related to H1N1. The infection was confirmed in nasopharyngeal aspirate, stools and cerebrospinal fluid by real-time PCR. Treatment with oseltamivir was started.info:eu-repo/semantics/publishedVersio

Pentaquarks in the Jaffe-Wilczek approximation

The masses of $uudd\bar s$, $uudd\bar d$ and $uuss\bar d$ pentaquarks are evaluated in a framework of both the Effective Hamiltonian approach to QCD and spinless Salpeter using the Jaffe--Wilczek diquark approximation and the string interaction for the diquark--diquark--antiquark system. The pentaquark masses are found to be in the region above 2 GeV. That indicates that the Goldstone boson exchange effects may play an important role in the light pentaquarks. The same calculations yield the mass of $[ud]^2\bar c$ pentaquark $\sim$ 3250 MeV and $[ud]^2\bar b$ pentaquark $\sim$ 6509 MeV.Comment: 14 pages, 2 tables, LaTeX2e. References correcte

Structural and Microanalytical Studies of CrO2 Thin Films on c-Sapphire by High Resolution Electron Microscopy Methods

Chromium dioxide (CrO2) has been extensively used in the magnetic recording industry. However, it is its ferromagnetic half-metallic nature that has more recently attracted much attention, primarily for the development of spintronic devices. CrO2 is the only stoichiometric binary oxide theoretically predicted to be fully spin polarized at the Fermi level. It presents a Curie temperature of ∼ 396 K, i.e. well above room temperature, and a magnetic moment of 2 mB per formula unit. However an antiferromagnetic native insulating layer of Cr2O3 is always present on the CrO2 surface which enhances the CrO2 magnetoresistance and might be used as a barrier in magnetic tunnel junctions

Quantum repeaters and quantum key distribution: analysis of secret key rates

We analyze various prominent quantum repeater protocols in the context of long-distance quantum key distribution. These protocols are the original quantum repeater proposal by Briegel, D\"ur, Cirac and Zoller, the so-called hybrid quantum repeater using optical coherent states dispersively interacting with atomic spin qubits, and the Duan-Lukin-Cirac-Zoller-type repeater using atomic ensembles together with linear optics and, in its most recent extension, heralded qubit amplifiers. For our analysis, we investigate the most important experimental parameters of every repeater component and find their minimally required values for obtaining a nonzero secret key. Additionally, we examine in detail the impact of device imperfections on the final secret key rate and on the optimal number of rounds of distillation when the entangled states are purified right after their initial distribution.Comment: Published versio

Cardiopulmonary complications in a patient with bezoar

We report a case of a 17-year-old institutionalised male with a medical history of fragile X syndrome, bilateral congenital glaucoma, cataracts and pica disorder. He was transferred to our paediatric intensive care unit owing to respiratory failure and hypotension. On transoesophageal echocardiogram, he presented left atrium compression. A CT of the thorax and mediastinum revealed an unknown heterogeneous material in the lumen of the stomach and oesophagus, with a lung parenchyma suggestive of alveolar foreign material. Endoscopic evaluation showed diaper fragments inside the oesophagus and stomach. Fragmentation and suction of diaper material was made. Medical treatment was performed with inotropic support, conventional mechanical ventilation and antibiotics

PERCUTANEOUS KIDNEY BIOPSY: eight years-experience

A biópsia renal constitui um instrumento fundamental para o diagnóstico e prognóstico de diversas patologias nefrológicas e sistémicas. No nosso Hospital a sua realização iniciou-se em 1994, tendo sido biopsado um doente com Doença de Berger. Até à data foram efectuadas 91 biópsias renais percutâneas com a seguinte distribuição anual: 1994 (n=3), 1995 (n=3), 1996 (n=3), 1997 (n=15), 1998 (n=5), 1999 (n=23), 2000 (n=13), 2001 (n=26) em 57 homens e 34 mulheres. Foi utilizada orientação ecográfica e na maioria dos casos a agulha de Vim Silverman (14G). Apenas em cinco casos se utilizou uma pistola automática BARD. Era nosso objectivo, em cada biópsia, a colheita de pelo menos dois fragmentos, um para microscopia óptica e outro para imunoflurescência. Os grandes síndromas nefrológicos que conduziram a este exame foram: síndroma nefrótico (n=27), anormalidades urinárias assintomáticas (n=25), insuficiência renal aguda ou rápidamente progressiva (n=18), insuficiência renal crónica (n=15), hipertensão arterial (n=4) e glomerulonefrite aguda (n=2). Em 92.3% (84/91) dos casos foi possível efectuar um diagnóstico histológico por microscopia óptica. Se considerarmos, no entanto, sete casos com suspeita clínica de nefropatia IgA em que o fragmento colhido para imunoflurescência não continha glomérulos, a eficácia diminuiu para 84.6% (77/91). O número médio de glomérulos por amostra foi de 18.3 ± 14.2 [0-80]. Os diagnósticos histológico obtidos foram os seguintes: doença de Berger (n=24), diversas formas de síndroma nefrótico primário (n=18), nefrite lúpica (n=8), glomerulonefrite mesangioproliferativa, sem glomérulos na imunoflurescência (n=6), ausência de tecido renal ou de glomérulos nas amostras (n=6), síndroma nefrótico secundário (n=4), nefrite túbulo-intersticial ou necrose tubular aguda (n=4), nefropatia diabética (n=3), rim de mieloma (n=3), glomerulonefrite crescêntica sem depósitos imunes (n=3), nefroangiosclerose hipertensiva (n=2), glomerulonefrite mesangioproliferativa IgM (n=2) e outros (n=8). A hematúria macroscópica revelou-se como a complicação mais frequente (n=9; 9.9%). Apenas em três casos se verificou a existência de hematoma renal ecograficamente (3.3%). A saída de sangue pelo mandril da agulha de biópsia surgiu em quatro casos (4.4%) e foi necessário proceder à transfusão de concentrado de glóbulos rubros em três doentes (3.3%). Registamos uma punção acidental de baço. Em nenhum caso foi necessário efectuar nefrectomia por hemorragia incontrolável. Identificamos, como índices de mau prognóstico relativamente à evolução para insuficiência renal crónica avançada (n=2) ou terminal (n=15), o maior número de glomérulos esclerosados (30% vs 8%; p<0.01) e de lesões túbulo-intersticiais (100% vs 63%; p<0.01). Em conclusão, a biópsia renal efectuada com orientação ecográfica permitiu a obtenção 21 de amostras com valor diagnóstico em 84.6% dos casos. A taxa de complicações foi relativamente baixa comparando com outras séries. Verificamos um progressivo aumento de qualidade das amostras renais colhidas, em relação directa com uma coordenação técnica crescente entre os nefrologistas e radiologistas intervenientes.nephrological and systemic pathologies. At our institution the first patient submitted to this technique, at 1994, showed Berger disease. Until 2002 we have performed 91 renal biopsies (57 men and 34 women) with the following annual distribution: 1994 (n=3), 1995 (n=3), 1996 (n=3), 1997 (n=15), 1998 (n=5), 1999 (n=23), 2000 (n=13) and 2001 (n=26). Ultrasound guidance was always used and in most of cases the technique was performed with Vim-Silverman (14G) needle. BARD automatic system was employed in only five patients. The clinical diagnosis that lead to renal biopsy were: nephrotic syndrome (n=27), asyntomatic urinary abnormalities (n=25), acute or rapidly progressive renal failure (n=18), chronic renal failure (n=15), hypertension (n=4) and acute nephritis (n=2). The efficacy for optic histological diagnosis was 92.3% (84/91). However, if we include seven cases of presumed IgA nephropathy that don’t included fragment for immunofluorescence (IF) analysis the efficacy declined to 84.6% (77/91). The mean number of glomeruli per fragment was 18.3 ± 14.2 [0-80]. Histological diagnosis were the following: Berger disease (n=24), idiopathic nephrotic syndrome (n=18), lupus nephritis (n=8), mesangial proliferative glomerulonephritis without glomeruli in the IF fragment (n=6), without glomeruli (n=6), secondary nephrotic syndrome (n=4), tubulointerstitial nephritis or acute tubular necrosis (n=4), diabetic nephropathy (n=3), myeloma kidney (n=3), pauci-imune and crescentic glomerulonephritis (n=3), hypertensive nephropathy (n=2), IgM mesangial proliferative glomerulonephritis (n=2) and various (n=8). Gross hematuria appeared in 9 patients (9.9%). Only in three of these patients it was showed, by ecography, the existence of kidney haematoma. Bleeding throughout the mandrill in four cases, leaded to transfusion in only three patients. We have registered one accidental spleen puncture. Nephrectomy for incontrollable bleeding was never needed. Higher glomerulosclerosis (30% vs 8%; p<0.01) and also a greater extent of tubulointersticial lesions (100% vs 63%; p<0.01), were predictors of progression into end-stage or advanced renal failure. Concluding, renal biopsy with ultrasound guidance was valuable for diagnosis in 84.6% of our proceedings. Our serie is similar to others concerning serious complications. Nephrologists and radiologists improved progressively their coordination performing this technique, improving the results during this period of 8 years