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An extensive numerical analysis of the scattering and transport properties of the power-law banded random matrix model (PBRM) at criticality in the presence of orthogonal, unitary, and symplectic symmetries is presented. Our results show a good agreement with existing analytical expressions in the metallic regime and with heuristic relations widely used in studies of the PBRM model in the presence of orthogonal and unitary symmetries. Moreover, our results confirm that the multifractal behavior of disordered systems at criticality can be probed by measuring scattering and transport properties, which is of paramount importance from the experimental point of view. Thus, a full picture of the scattering and transport properties of the PBRM model at criticality corresponding to the three classical Wigner-Dyson ensembles is provided.
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Transmission measurements through three-port microwave graphs are performed, in analogy to three-terminal voltage drop devices with orthogonal, unitary, and symplectic symmetry. The terminal used as a probe is symmetrically located between two chaotic subgraphs, and each graph is connected to one port, the input and the output, respectively. The analysis of the experimental data clearly exhibits the weak localization and antilocalization phenomena. We find a good agreement with theoretical predictions, provided that the effects of dissipation and imperfect coupling to the ports are taken into account.
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We study the voltage drop along three-terminal disordered wires in all transport regimes, from the ballistic to the localized regime. This is performed by measuring the voltage drop on one side of a one-dimensional disordered wire in a three-terminal setup as a function of disorder. Two models of disorder in the wire are considered: (i) the one-dimensional Anderson model with diagonal disorder and (ii) finite-width bulk-disordered waveguides. Based on the known ß dependence of the voltage drop distribution of the three-terminal chaotic case, ß being the Dyson symmetry index (ß=1, 2, and 4 for orthogonal, unitary, and symplectic symmetries, respectively), the analysis is extended to a continuous parameter ß>0 and uses the corresponding expression as a phenomenological one to reach the disordered phase. We show that our proposal encompasses all the transport regimes with ß depending linearly on the disorder strength.
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Coherent transport phenomena are difficult to observe due to several sources of decoherence. For instance, in the electronic transport through quantum devices the thermal smearing and dephasing, the latter induced by inelastic scattering by phonons or impurities, destroy phase coherence. In other wave systems, the temperature and dephasing may not destroy the coherence and can then be used to observe the underlying wave behaviour of the coherent phenomena. Here, we observe coherent transmission of mechanical waves through a two-dimensional elastic Sinai billiard with two waveguides. The flexural-wave transmission, performed by non-contact means, shows the quantization when a new mode becomes open. These measurements agree with the theoretical predictions of the simplest model highlighting the universal character of the transmission fluctuations.
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This study focused on the study of the changes originated in the milk from partum until d 90 of lactation. Ten multiparous Majorera goats, bred carefully under animal health standards, with a litter size of 2 kids (the average in this breed is 1.83 prolificacy) and similar gestation length (149 ± 1 d) were used. Goat kids were removed from their dams to avoid interferences with the study. Compositional content (fat, protein, and lactose) were measured, as well as some other properties, including pH, density, titratable acidity, ethanol stability, rennet clotting time, and somatic cell count. Moreover, immunity molecules (IgG, IgA, and IgM concentrations and chitotriosidase activity) received great attention. Fat and protein content were higher in the first days postpartum, whereas lactose content was lower. Density, titratable acidity, rennet clotting time, and somatic cell count decreased throughout the lactation period, whereas pH and ethanol stability increased. Relative to the immunological parameters, each measured parameter obtained its maximum level at d 0, showing the first milking as the choice to provide immunity to the newborn kids. On the other hand, this study might be used to establish what the best use is: processing or kid feeding.
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Colostro/química , Colostro/imunologia , Leite/química , Leite/imunologia , Animais , Contagem de Células , Fenômenos Químicos , Quimosina/química , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Feminino , Cabras , Hexosaminidases/metabolismo , Concentração de Íons de Hidrogênio , Imunoglobulina A/química , Imunoglobulina G/química , Imunoglobulina M/química , Lactação , Ácido Láctico/química , Lactose/química , Paridade , Período Pós-Parto , GravidezRESUMO
The consumer trend for healthier food choices and preferences for low-fat products has increased the interest in low-fat cheese and nutraceutical dairy products. However, consumer preference is still for delicious food. Low- and reduced-fat cheeses are not completely accepted because of their unappealing properties compared with full-fat cheeses. The method reported here provides another option to the conventional cheese-making process to obtain lower fat cheese. Using CO(2) as a supercritical fluid offers an alternative to reduce fat in cheese after ripening, while maintaining the initial characteristics and flavor. The aim of this experiment was to evaluate the effect of pressure (10, 20, 30, and 40 × 10(6) Pa) of supercritical CO(2) on the amount of fat extracted, microbial population, polar lipid profile, and microstructure of 2 varieties of goat cheese: Majorero, a protected denomination of origin cheese from Spain, and goat Gouda-type cheese. The amount of fat was reduced 50 to 57% and 48 to 55% for Majorero and goat Gouda-type cheeses, respectively. Higher contents (on a fat basis) of sphingomyelin and phosphatidylcholine were found in Majorero cheese compared with control and goat Gouda-type cheeses. The microbial population was reduced after supercritical fluid extraction in both cheeses, and the lethality was higher as pressure increased in Majorero cheese, most noticeably on lactococcus and lactobacillus bacteria. The Gouda-type cheese did not contain any lactobacilli. Micrographs obtained from confocal laser scanning microscopy showed a more open matrix and whey pockets in the Majorero control cheese. This could explain the ease of extracting fat and reducing the microbial counts in this cheese after treatment with supercritical CO(2). Supercritical fluid extraction with CO(2) has great potential in the dairy industry and in commercial applications. The Majorero cheese obtained after the supercritical fluid extraction treatment was an excellent candidate as a low-fat goat cheese, lower in triglycerides and cholesterol but still with all the health benefits inherent in goat milk.
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Queijo/análise , Lipídeos/análise , Animais , Carga Bacteriana , Queijo/microbiologia , Queijo/normas , Cromatografia com Fluido Supercrítico/métodos , Qualidade dos Alimentos , Tecnologia de Alimentos/métodos , Cabras , PressãoRESUMO
We study the scattering of waves in systems with losses or gains simulated by imaginary potentials. This is done for a complex delta potential that corresponds to a spatially localized absorption or amplification. In the Argand plane the scattering matrix moves on a circle C centered on the real axis, but not at the origin, that is tangent to the unit circle. From the numerical simulations it is concluded that the distribution of the scattering matrix, when measured from the center of the circle C, agrees with the nonunitary Poisson kernel. This result is also obtained analytically by extending the analyticity condition, of unitary scattering matrices, to the no-unitary ones. We use this nonunitary Poisson kernel to obtain the distribution of nonunitary scattering matrices when measured from the origin of the Argand plane. The obtained marginal distributions have excellent agreement with the numerical results.
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Algoritmos , Transferência de Energia , Modelos Teóricos , Reologia/métodos , Simulação por ComputadorRESUMO
Therapeutic options for developing countries have to assure an optimum safety and efficacy and low-cost antihaemophilic concentrates. A single blind randomized crossover study was carried out in 12 previously treated HB patients, comparing the pharmacokinetics (PK), thrombogenicity (TG) and safety of two plasma-derived double-inactivated (solvent/detergent heating at 100 degrees C, 30 min) factor IX (FIX) concentrates, UMAN COMPLEX DI (product A) [plasma-derived prothrombin concentrates (PCC)] and a high purity FIX concentrate AIMAFIX DI (product B, HPFIX). In a non-bleeding state, they received one single intravenous dose 50 IU FIX kg(-1) of PCC or HPFIX, and after a wash-out period of 14 days, the other product. We evaluated acute tolerance and determined PK parameters based on FIX levels measured over a 50 h postinfusion period. We studied fibrinogen, platelets, antithrombin, F1 + 2, TAT, D-dimer, over a 360 min postinfusion period. Ten cases remained in on-demand treatment for 6 months, five with PCC and five with HPFIX. PK and anti-FIX inhibitors were repeated at 3 and 6 months. No inhibitors were detected. PK values (PCC vs. HPFIX): clearence (CL; mL h(-1) kg(-1)) 5.2 +/- 1.4 vs. 6.5 +/- 1.4; the volume of distribution at steady state (mL kg(-1)) 154.9 +/- 54.9 vs. 197.5 +/- 72.5; mean residence time (h) 29.7 +/- 8.1 vs. 30.7 +/- 9.2; T(1/2) (h) 22.3 +/- 7 vs. 23.5 +/- 12.3; incremental recovery (IR; U dL(-1) U(-1) kg(-1)) 0.96 +/- 0.17 vs. 0.76 +/- 0.13. HPFIX showed significant lower IR and higher CL. There were no differences in PK at 3 and 6 months. In TG, significant increments in TAT and F1 + 2 at 30 min and 6 h were found with PCC. Product B PK results agrees with reported results for other HPFIX preparations. Use of PCC product A has to consider its thrombogenic activity.
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Fatores de Coagulação Sanguínea/administração & dosagem , Fator IX/administração & dosagem , Hemofilia B/tratamento farmacológico , Adolescente , Adulto , Antitrombina III/análise , Biomarcadores/sangue , Fatores de Coagulação Sanguínea/farmacocinética , Estudos Cross-Over , Fator IX/farmacocinética , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Hemofilia B/sangue , Hemofilia B/fisiopatologia , Hemostasia/fisiologia , Humanos , Injeções Intravenosas , Fragmentos de Peptídeos/análise , Peptídeo Hidrolases/sangue , Contagem de Plaquetas/métodos , Protrombina/análise , Método Simples-CegoRESUMO
El tracto digestivo es el órgano inmune más grande de la economía corporal. A su vez es el que está más expuesto a cargas antigénicas y es por esto que los pacientes con el Síndrome de Inmunodeficiencia Humana (SIDA), con mucha frecuencia tienen síntomas originados en el mismo. Nos proponemos presentar una revisión actualizada de las anormalidades o patologías hepatobiliares que pueden en un momento determinado afectar a los pacientes con SIDA
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Humanos , Masculino , Adulto , Doenças Biliares/etiologia , Hepatite Viral Humana/etiologia , Hepatopatias/etiologia , Síndrome da Imunodeficiência Adquirida/complicaçõesRESUMO
Seventy-three patients with Stage III abdominal non-Hodgkin's lymphoma were prospectively treated following two sequential protocols (P): L278 P (group A, 33 patients) (1978-1983) and L384 P (group B, 40 patients), (1984-1991). No patient received radiotherapy. The L278 P included 7 drugs: cyclophosphamide, vincristine (VCR), adriamycin (ADR), prednisone, methotrexate (MTX), dexamethasone, and 6-mercaptopurine, given for remission induction, maintenance, and CNS prophylaxis. In the L384 P we introduced a consolidation phase consisting of intravenous MTX and citrovorum factor rescue, and IV cytosine arabinoside. VCR was also added to the monthly doses and the maintenance phase was reduced from 18 to 15 months. From January 1988 we changed ADR for epirubicin in the same doses. Prophylactic treatment of the CNS, in the L384 P, was intensified by increasing the number of doses of MTX IT in the remission, induction, and consolidation phases, and with the use of ara-C IT. Laparotomy in 50 patients allowed partial resection in 16, and second-look laparotomy was performed in 27 patients. Viable tumor was found in four patients. Three patients (G-A) died from metabolic complications and another 4 (2 G-A and 2 G-B) failed to attain CR and died. A total of 28 (85%) of 33 children of G-A and 38 (95%) of 40 children in G-B achieved CR. Five children died in remission (2 G-A, 3 G-B). Three patients (G-A) relapsed in the CNS and one (G-B) relapsed in the abdomen and died. Disease-free survival at 120 months was 70% in G-A and 84% in G-B.