Sine-Gordon soliton as a model for Hawking radiation of moving black holes and quantum soliton evaporation

The intriguing connection between black holes' evaporation and physics of solitons is opening novel roads to finding observable phenomena. It is known from the inverse scattering transform that velocity is a fundamental parameter in solitons theory. Taking this into account, the study of Haw\-king radiation by a moving soliton gets a growing relevance. However, a theoretical context for the description of this phenomenon is still lacking. Here, we adopt a soliton geometrization technique to study the quantum emission of a moving soliton in a one-dimensional model. Representing a black hole by the one soliton solution of the sine-Gordon equation, we consider Haw\-king emission spectra of a quantized massless scalar field on the soliton-induced metric. We study the relation between the soliton velocity and the black hole temperature. Our results address a new scenario in the detection of new physics in the quantum gravity panorama.Comment: 8 pages, 4 figure

Human Growth: parameters and reflections about growth references

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Editorial

Chegamos à maioridade! Aqui está o 3º fascículo do décimo oitavo volume da Revista Brasileira de Crescimento e Desenvolvimento Humano. São exatamente dezoito anos de vida de uma idéia bem sucedida

Ratio of weight to height gain: a useful tool for identifying children at risk of becoming overweight or obese at preschool age

PURPOSE: To analyze the usefulness of the weight gain/height gain ratio from birth to two and three years of age as a predictive risk indicator of excess weight at preschool age. METHODS: The weight and height/length of 409 preschool children at daycare centers were measured according to internationally recommended rules. The weight values and body mass indices of the children were transformed into a z-score per the standard method described by the World Health Organization. The Pearson correlation coefficients (rP) and the linear regressions between the anthropometric parameters and the body mass index z-scores of preschool children were statistically analyzed (alpha = 0.05). RESULTS: The mean age of the study population was 3.2 years (± 0.3 years). The prevalence of excess weight was 28.8%, and the prevalence of overweight and obesity was 8.8%. The correlation coefficients between the body mass index z-scores of the preschool children and the birth weights or body mass indices at birth were low (0.09 and 0.10, respectively). There was a high correlation coefficient (rP = 0.79) between the mean monthly gain of weight and the body mass index z-score of preschool children. A higher coefficient (rP = 0.93) was observed between the ratio of the mean weight gain per height gain (g/cm) and the preschool children body mass index z-score. The coefficients and their differences were statistically significant. CONCLUSION: Regardless of weight or length at birth, the mean ratio between the weight gain per g/cm of height growth from birth presented a strong correlation with the body mass index of preschool children. These results suggest that this ratio may be a good indicator of the risk of excess weight and obesity in preschool-aged children.Research Support Foundation of the State of Sao Paulo (Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

RADIATIVE RECOMBINATION IN THE PRESENCE OF A FEW CYCLE LASER PULSE

We have investigated the laser-assisted radiative recombination in the presence of a few-cycle pulse with the aim of demonstrating means of controlling such process. Within the Coulomb-Volkov approach already employed to describe the radiative recombination assisted by a monochromatic laser field, we have found that the emitted photon spectrum is affected by both the cycle number n(c) and the carrier-envelope relative phase.. In particular, it has been shown that the minimum and the maximum values of the emitted photon energy may be controlled by varying nc and.. Finally, it has been found that the enhancement of radiative recombination occurring in the presence of a monochromatic field, takes place also by using a few-cycle laser pulse

Fruit intake and obesity Fruit and vegetables consumption and obesity in Brazil

Introduction: Obesity affects more than half of the adult population and correlates with the development of chronic and psychosocial diseases. The consumption of fruits and vegetables (FV) is a protective factor for obesity, but their consumption is often below the recommendations. Objective: To identify the level of fruit consumption in human development cycles, as well as the data on the association of fruit consumption with excess weight in Brazil. Methods: A non-systematic literature review on the Virtual Health Library (VHL) databases for the period 2005 to 2015. A total of 23 studies were selected in the English and Portuguese languages, according to the study design and population group. Only cohorts and cross sections studies in Brazil were selected. Appropriate FV consumption was considered to be 400 g/day or a frequency of 5 servings/day (3 servings/day of fruits), and overweight was evaluated according to each age group and development cycle. Results: The average consumption for pregnant women was found to be 350 g/day; an inverse relationship was found between total fi bre consumption and gestational weight gain. The average consumption of FV for children and adolescents has remained between 30% and 40%, consumption falling with increasing age. Vigitel data between 2006 and 2014 shows an increase in the prevalence of adequate consumption of FV for adults and seniors according to gender, age and education. Appropriate consumption tripled during this period. There was an association between fruit consumption and weight loss, increased risk of obesity, abdominal obesity, hypertriglyceridemia and presence of metabolic syndrome (SM). Conclusions: The prevalence of adequate consumption of FV is low in all regions of Brazil and among all age groups, the highest prevalence is among women and increases with the advance of age, higher education level and higher socioeconomic status. Adequate fruit consumption correlates to weight loss and/or weight gain control of individuals

Interference Effects in Photodetachment of F- in a Strong Circularly Polarized Laser Pulse

A numerical simulation of photodetachment of F- by a circularly polarized laser pulse has been accomplished by using a Keldysh-type approach. The numerical results are in agreement with measurements of photoelectron energy spectra recently reported in the literature. The features exhibited by the spectra are traced back to quantum interference effects, in the same spirit as in a double-slit experiment in the time domain

Growth of very low birth weight infants fed with milk from a human milk bank selected according to the caloric and protein value

OBJECTIVE: To describe growth and clinical evolution of very low birth weight infants fed during hospital stay with milk from a human milk bank according to the caloric-protein value. METHOD: Forty very low birth weight infants were included: 10 were fed milk from their own mothers (GI), and 30 were fed human milk bank &gt; 700 cal/L and 2 g/dL of protein. Growth curves were adjusted using nonlinear regression to the measured growth parameters. RESULTS: full enteral diet was reached in 6.3 days by GI and in 10.8 by GII; a weight of 2 kg was reached in 7.3 weeks for GI and in 7.8 for GII. In GI, 3/10 (33.3%) and in GII, 7/30 (23.3%) developed sepsis. Necrotizing enterocolitis did not occur in GI, but in 3/30 (10.0%) in GII. GI presented with urinary calcium &gt; 4 mg/L in 1/10 (10.0%), urinary phosphorus (Pu) <1 mg/L in 10/10 (100%), and Ca/Cr &gt;0.6 ratio in 1/10 (10.0%) of the cases; in GII, no children presented alterations of the urinary calcium or the Ca and Cr ratio, and Pu was <1 mg/L in 19/30 (63.3%). In terms of growth the 50th percentile for GI was a weight gain of 12.1 g/day (GI) vs. 15.8 g/day (GII), a length gain of 0.75 cm/week (GI) vs. 1.02 cm/week (GII), and a head circumference gain of 0.74 cm/week (GI) vs. 0.76 cm/week (GII). CONCLUSIONS: Human milk bank allowed a satisfactory growth and good clinical evolution for very low birth weight infants

Structural characterization of syndiotactic propylene-styrene-ethylene terpolymers

The structural features of propylene-styrene-ethylene terpolymer (sP/(S-E)) prepd. using syndiospecific Cs-sym. metallocene catalyst, isopropylidene(cyclopentadienyl)-(9-fluorenyl)zirconium dichloride with MAO co-catalyst were studied. The polymorphism studies of as-prepd., melt-crystd., and fiber sP/(S-E) confirmed that ethylene units are mainly bound to styrene units arising from catalyst reactivation after the secondary insertion of styrene. Styrene-ethylene units are mainly segregated in the amorphous phase. The bulky styrene units, bound to ethylene, prevent the inclusion of ethylene units in the crystals of syndiotactic polypropylene (sPP), as generally occurs for copolymers of sPP with ethylene. This explains the fact that the effect of styrene-ethylene units on polymorphism of sPP is smaller than that obsd. in copolymers of sPP contg. only ethylene or butene comonomer units