Canonical quantum potential scattering theory

A new formulation of potential scattering in quantum mechanics is developed using a close structural analogy between partial waves and the classical dynamics of many non-interacting fields. Using a canonical formalism we find nonlinear first-order differential equations for the low-energy scattering parameters such as scattering length and effective range. They significantly simplify typical calculations, as we illustrate for atom-atom and neutron-nucleus scattering systems. A generalization to charged particle scattering is also possible.

Analysis of breast cancer by small angle X-ray scattering (SAXS)

Small angle X-ray scattering (SAXS) images of normal breast tissue and benign and malignant breast tumour tissues, fixed in formalin, were measured at the momentum transfer range of 0.063 nm(-1) <= q (=4 pi sin(theta/2)/lambda) <= 2.720 nm(-1). Four intrinsic parameters were extracted from the scattering profiles (1D SAXS image reduced) and, from the combination of these parameters, another three parameters were also created. All parameters, intrinsic and derived, were subject to discriminant analysis, and it was verified that parameters such as the area of diffuse scatter at the momentum transfer range 0.50 <= q <= 0.56 nm(-1), the ratio between areas of fifth-order axial and third-order lateral peaks and third-order axial spacing provide the most significant information for diagnosis (p < 0.001). Thus, in this work it was verified that by combining these three parameters it was possible to classify human breast tissues as normal, benign lesion or malignant lesion with a sensitivity of 83% and a specificity of 100%.

The qWR star HD 45166 - II. Fundamental stellar parameters and evidence of a latitude-dependent wind

Context. The enigmatic object HD 45166 is a qWR star in a binary system with an orbital period of 1.596 day, and presents a rich emission-line spectrum in addition to absorption lines from the companion star (B7 V). As the system inclination is very small (i = 0.77 degrees +/- 0.09 degrees), HD 45166 is an ideal laboratory for wind-structure studies. Aims. The goal of the present paper is to determine the fundamental stellar and wind parameters of the qWR star. Methods. A radiative transfer model for the wind and photosphere of the qWR star was calculated using the non-LTE code CMFGEN. The wind asymmetry was also analyzed using a recently-developed version of CMFGEN to compute the emerging spectrum in two-dimensional geometry. The temporal-variance spectrum (TVS) was calculated to study the line-profile variations. Results. Abundances and stellar and wind parameters of the qWR star were obtained. The qWR star has an effective temperature of T(eff) = 50 000 +/- 2000 K, a luminosity of log(L/L(circle dot)) = 3.75 +/- 0.08, and a corresponding photospheric radius of R(phot) = 1.00 R(circle dot). The star is helium-rich (N(H)/N(He) = 2.0), while the CNO abundances are anomalous when compared either to solar values, to planetary nebulae, or to WR stars. The mass-loss rate is. M = 2.2 x 10(-7) M(circle dot) yr(-1), and the wind terminal velocity is v(infinity) = 425 km s(-1). The comparison between the observed line profiles and models computed under different latitude-dependent wind densities strongly suggests the presence of an oblate wind density enhancement, with a density contrast of at least 8: 1 from equator to pole. If a high velocity polar wind is present (similar to 1200 km s(-1)), the minimum density contrast is reduced to 4:1. Conclusions. The wind parameters determined are unusual when compared to O-type stars or to typical WR stars. While for WR stars v(infinity)/v(esc) > 1.5, in the case of HD 45166 it is much smaller (v(infinity)/v(esc) = 0.32). In addition, the efficiency of momentum transfer is eta = 0.74, which is at least 4 times smaller than in a typical WR. We find evidence for the presence of a wind compression zone, since the equatorial wind density is significantly higher than the polar wind. The TVS supports the presence of such a latitude-dependent wind and a variable absorption/scattering gas near the equator.

Self-assembling of phenothiazine compounds investigated by small-angle X-ray scattering and electron paramagnetic resonance spectroscopy

Small-angle X-ray scattering (SAXS) and electron paramagnetic resonance (EPR) have been carried out to investigate the structure of the self-aggregates of two phenothiazine drugs, chlorpromazine (CPZ) and trifluoperazine (TFP), in aqueous solution. In the SAXS studies, drug solutions of 20 and 60 mM, at pH 4.0 and 7.0, were investigated and the best data fittings were achieved assuming several different particle form factors with a homogeneous electron density distribution in respect to the water environment. Because of the limitation of scattering intensity in the q range above 0.15 angstrom(-1), precise determination of the aggregate shape was not possible and all of the tested models for ellipsoids, cylinders, or parallelepipeds fitted the experimental data equally well. The SAXS data allows inferring, however, that CPZ molecules might self-assemble in a basis set of an orthorhombic cell, remaining as nanocrystallites in solution. Such nanocrystals are composed of a small number of unit cells (up to 10, in c-direction), with CPZ aggregation numbers of 60-80. EPR spectra of 5- and 16-doxyl stearic acids bound to the aggregates were analyzed through simulation, and the dynamic and magnetic parameters were obtained. The phenothiazine concentration in EPR experiments was in the range of 5-60 mM. Critical aggregation concentration of TFP is lower than that for CPZ, consistent with a higher hydrophobicity of TFP. At acidic pH 4.0 a significant residual motion of the nitroxide relative to the aggregate is observed, and the EPR spectra and corresponding parameters are similar to those reported for aqueous surfactant micelles. However, at pH 6.5 a significant motional restriction is observed, and the nitroxide rotational correlation times correlate very well with those estimated for the whole aggregated particle from SAXS data. This implies that the aggregate is densely packed at this pH and that the nitroxide is tightly bound to it producing a strongly immobilized EPR spectrum. Besides that, at pH 6.5 the differences in motional restriction observed between 5- and 16-DSA are small, which is different from that observed for aqueous surfactant micelles.

Study of (9)Be+(12)C elastic scattering at energies near the Coulomb barrier

In this work, angular distribution measurements for the elastic channel were performed for the (9)Be + (12)C reaction at the energies E(Lab) = 13.0, 14.5, 17.3, 19.0 and 21.0 MeV, near the Coulomb barrier. The data have been analyzed in the framework of the double folding Sao Paulo potential. The experimental elastic scattering angular distributions were well described by the optical potential at forward angles for all measured energies. However, for the three highest energies, an enhancement was observed for intermediate and backward angles. This can be explained by the elastic transfer mechanism. (C) 2011 Elsevier B.V. All rights reserved.

Thermal stability of extracellular hemoglobin of Glossoscolex paulistus: Determination of activation parameters by optical spectroscopic and differential scanning calorimetric studies

Glossoscolex paulistus hemoglobin (HbGp) was studied by dynamic light scattering (DLS), optical absorption spectroscopy (UV-VIS) and differential scanning calorimetry (DSC). At pH 7.0, cyanomet-HbGp is very stable, no oligomeric dissociation is observed, while denaturation occurs at 56 degrees C, 4 degrees C higher as compared to oxy-HbGp. The oligomeric dissociation of HbGp occurs simultaneously with some protein aggregation. Kinetic studies for oxy-HbGp using UV-VIS and DES allowed to obtain activation energy (E(a)) values of 278-262 kJ/mol (DES) and 333 kJ/mol (UV-VIS). Complimentary DSC studies indicate that the denaturation is irreversible, giving endotherms strongly dependent upon the heating scan rates, suggesting a kinetically controlled process. Dependence on protein concentration suggests that the two components in the endotherms are due to oligomeric dissociation effect upon denaturation. Activation energies are in the range 200-560 kJ/mol. The mid-point transition temperatures were in the range 50-65 degrees C. Cyanomet-HbGp shows higher mid-point temperatures as well as activation energies, consistent with its higher stability. DSC data are reported for the first time for an extracellular hemoglobin. (C) 2010 Elsevier B.V. All rights reserved.

Comparison of periodontal parameters in individuals with syndromic craniosynostosis

Craniosynostosis syndromes are characterized by premature closure of one or more cranial sutures, associated with other malformations, the most frequent of which are the Crouzon and Apert syndromes. Few studies in the literature have addressed the oral health of these individuals. The purpose of this study was to compare the periodontal status of individuals with Apert, Crouzon, Pfeiffer and Saethre-Chotzen syndromes before toothbrushing and compare the efficiency of plaque removal before and after mechanical toothbrushing. The probing depth, plaque index (according to Löe and O'Leary), clinical attachment level, gingival index (according to Silness and Löe) and amount of keratinized mucosa were evaluated before toothbrushing, and the O'Leary plaque index was assessed before and immediately after toothbrushing, on the same day, in 27 individuals aged 11 to 36 years. There was statistically significant difference in the mean probing depth and clinical attachment level among regions (p=0.00; p=0.01, respectively). The gingival index did not reveal statistically significant differences. With regard to the plaque index, the left region exhibited higher plaque index values than the right and anterior regions. No significant results were found in the analysis of keratinized mucosa. Comparison of the O'Leary plaque index before and after toothbrushing revealed statistically significant difference for all syndromes except for the Pfeiffer syndrome (p<0.05). In conclusion, there was no difference in the periodontal status among individuals with syndromic craniosynostosis. The posterior region was more affected than the anterior region as to the presence of plaque, loss of insertion and probing depth. Individuals with Pfeiffer syndrome exhibited greater toothbrushing efficiency than individuals with the other craniosynostosis syndromes.

Impact of adiposity on immunological parameters

Studies evaluating immune function in obese humans and experimental animals indicate that the excess adiposity is associated with impaired in immune responses. Obesity is related to a higher rate of infections and to some types of cancer. Nutritional, metabolic and endocrine factors are implicated in the immunological changes. The adipose tissue directly produces substances with various functions related to immune system. Furthermore, some investigations suggest that certain types of weight reduction strategies can alter the immune function. Nevertheless, long-term studies should be carried out to address whether these changes positively affects the ability of these obese individuals to control infections and tumor development.

Multivariate analysis of the effects of soil parameters and environmental factors on the flavonoid content of leaves of Passiflora incarnata L., Passifloraceae

The aim of the present study was to evaluate the effect of soil characteristics (pH, macro- and micro-nutrients), environmental factors (temperature, humidity, period of the year and time of day of collection) and meteorological conditions (rain, sun, cloud and cloud/rain) on the flavonoid content of leaves of Passiflora incarnata L., Passifloraceae. The total flavonoid contents of leaf samples harvested from plants cultivated or collected under different conditions were quantified by high-performance liquid chromatography with ultraviolet detection (HPLC-UV/PAD). Chemometric treatment of the data by principal component (PCA) and hierarchic cluster analyses (HCA) showed that the samples did not present a specific classification in relation to the environmental and soil variables studied, and that the environmental variables were not significant in describing the data set. However, the levels of the elements Fe, B and Cu present in the soil showed an inverse correlation with the total flavonoid contents of the leaves of P. incarnata.

Growth parameters and mortality rate of the Scomber japonicus peruanus (Jordán & Hubb, 1925) along the Peruvian coast, South Pacific

The growth parameters and the mortality rates of the Scomber japonicus peruanus (Chub mackerel) were studied based on monthly data of frequency of fork length classes obtained from commercial landings off the Peruvian coast from 1996 to 1998. The asymptotic body length and growth rate values obtained by the ELEFAN I (Electronic Length Frequency Analysis) ranged from 40.20 cm to 42.20 cm and from 0.38 to 0.39, respectively. The oscillation amplitude was 0.60; the Winter point values varied from 0.50 to 0.60 and the performance index from 2.79 to 2.84. The total mortality rate of the Chub mackerel obtained by the linearized catch curve oscillated between 1.68 and 3.35. The rate of fishing mortality varied from 1.16 to 2.78 and the exploitation rate from 0.68 to 0.84. The annual rate of natural mortality estimated by the Pauly's method ranged from 0.52 to 0.53. The results obtained allow us to conclude that the longevity of the Chub mackerel was slightly over seven years.

Evaluation of left ventricular diastolic echocardiographic parameters in healthy dogs by pulsed-wave Doppler

Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E), peak A wave (peak A), E/A ratio (E/A), E wave deceleration time (EDT) and isovolumic relaxation time (IRVT) were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT), by age (peak A and E/A) and by body weight (TRIV). Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.

Yerba Maté (Ilex paraguariensis) aqueous extract decreases intestinal SGLT1 gene expression but does not affect other biochemical parameters in alloxan-diabetic wistar rats

Yerba mate´ (Ilex paraguariensis) is rich in polyphenols, especially chlorogenic acids. Evidence suggests that dietary polyphenols could play a role in glucose absorption and metabolism. The aim of this study was to evaluate the antidiabetic properties of yerba mate´ extract in alloxan-induced diabetic Wistar rats. Animals (n ) 41) were divided in four groups: nondiabetic control (NDC, n=11), and diabetic yerba maté (DY, n = 10). The intervention consisted in the administration of yerba mate´ extract in a 1 g extract/ kg body weight dose for 28 days; controls received saline solution only. There were no significant differences in serum glucose, insulin, and hepatic glucose-6-phosphatase activity between the groups that ingested yerba maté extract (NDY and DY) and the controls (NDC and DC). However, the intestinal SGLT1 gene expression was significantly lower in animals that received yerba maté both in upper (p = 0.007) and middle (p < 0.001) small intestine. These results indicate that bioactive compounds present in yerba maté might be capable of interfering in glucose absorption, by decreasing SGLT1 expression

Trajectory Sensitivity Method and Master-Slave Synchronization to Estimate Parameters of Nonlinear Systems

A combination of trajectory sensitivity method and master-slave synchronization was proposed to parameter estimation of nonlinear systems. It was shown that master-slave coupling increases the robustness of the trajectory sensitivity algorithm with respect to the initial guess of parameters. Since synchronization is not a guarantee that the estimation process converges to the correct parameters, a conditional test that guarantees that the new combined methodology estimates the true values of parameters was proposed. This conditional test was successfully applied to Lorenz's and Chua's systems, and the proposed parameter estimation algorithm has shown to be very robust with respect to parameter initial guesses and measurement noise for these examples. Copyright (C) 2009 Elmer P. T. Cari et al.

Estimation and prediction of parameters and breeding values in soybean using REML/BLUP and Least Squares

The aim of this study was to compare REML/BLUP and Least Square procedures in the prediction and estimation of genetic parameters and breeding values in soybean progenies. F(2:3) and F(4:5) progenies were evaluated in the 2005/06 growing season and the F(2:4) and F(4:6) generations derived thereof were evaluated in 2006/07. These progenies were originated from two semi-early, experimental lines that differ in grain yield. The experiments were conducted in a lattice design and plots consisted of a 2 m row, spaced 0.5 m apart. The trait grain yield per plot was evaluated. It was observed that early selection is more efficient for the discrimination of the best lines from the F(4) generation onwards. No practical differences were observed between the least square and REML/BLUP procedures in the case of the models and simplifications for REML/BLUP used here.

Electromagnetic energy within a magnetic infinite cylinder and scattering properties for oblique incidence

We analytically calculate the time-averaged electromagnetic energy stored inside a nondispersive magnetic isotropic cylinder that is obliquely irradiated by an electromagnetic plane wave. An expression for the optical-absorption efficiency in terms of the magnetic internal coefficients is also obtained. In the low absorption limit, we derive a relation between the normalized internal energy and the optical-absorption efficiency that is not affected by the magnetism and the incidence angle. This relation, indeed, seems to be independent of the shape of the scatterer. This universal aspect of the internal energy is connected to the transport velocity and consequently to the diffusion coefficient in the multiple scattering regime. Magnetism favors high internal energy for low size parameter cylinders, which leads to a low diffusion coefficient for electromagnetic propagation in 2D random media. (C) 2010 Optical Society of America