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We investigate the collision of a new class of topological defects that tends to become compact as a control parameter increases to larger and larger values. These new compactlike defects have, in general, more than one internal discrete mode depending on the value of the control parameter and, as usual, there is a critical velocity above which the defects escape after the collision. We noticed that below the critical velocity there are the windows of escape presenting fractal structure. An interesting novelty is the appearance of metastable structures with the formation of compactlike defects, maintaining a fixed distance from each other. Another new feature is the formation of boosted localized distributions of the scalar field which we called moving oscillons. These oscillons carry away almost all scalar field energy producing a complete disruption of the compactlike defects. The pattern of the moving oscillons depends on the control parameter, and becomes more complex as we increase its value. We conjecture that the new effects may be connected with the presence of more than one vibrational mode in the spectrum of the stability potential of the model under investigation. [ABSTRACT FROM AUTHOR]

We present a more detailed numerical investigation of the head-on collision of a two-kink/two-antikink system. We identified the escape of oscillon-like configurations as a pair of kinks of the standard ϕ4 model moving apart from each other. New pieces of evidence support that the lump-like defects can emerge from the two-kink interaction to form metastable configurations. Moreover, these configurations signalize the windows of escape that have a fractal structure similar to the n-bounce sequence when the kinks of ϕ4 interact. As the last piece of the numerical experiment, we show that by perturbing conveniently a lump-like defect, it is possible to recover another lump-like configuration as a metastable configuration. [ABSTRACT FROM AUTHOR]

Aim: To analyze possible factors associated with the quality of life (QoL) of mothers of preterm infants with very low birth weight (VLBW) during the first 3 years after delivery.Methods: The World Health Organization Quality of Life (WHOQOL)-bref scores were compared and correlated with maternal and infant-related sociodemographic and clinical variables at maternal discharge (T0) and at 6 (T1), 12 (T2), 24 (T3), and 36 (T4) months after delivery. Multiple linear regression models were fitted to investigate the effect of these variables on the mothers' QoL.Results: The WHOQOL-BREF physical domain scores were higher at T1 and T2 compared to T0 (p = 0.013). Maternal variables that contributed to maternal QoL scores (p < 0.05) were stable marital union (b = 13.60; T0), family income (b = -12.75; T3), Evangelical religion (b = 8.11; T4), and beck depression inventory (BDI) score (-1.42 ≤ b ≤ -0.36; T0, T1, T2, T3, and T4). Infants' variables that most affected maternal QoL (p < 0.05) were posthemorrhagic hydrocephalus (PHH) (-18.84 ≤ b ≤ -10.05; T1, T2, and T4), bronchopulmonary dysplasia (BPD) (b = -7.41; T2), female gender (b = 8.09; T2), and SNAPPE severity score (b = -0.23; T3).Conclusion: Mothers of preterm infants with VLBW exhibited transient improvements in physical well-being during the first year after delivery. The presence of depressive symptoms in mothers and the diagnosis of PHH or BPD were negatively associated with QoL. Social, religious, and economic aspects were also important factors for the QoL of mothers of preterm infants with VLBW. [ABSTRACT FROM AUTHOR]

The electric field gradients at Hg nuclei have been measured via the perturbed angular correlation (PAC) technique, allowing a full characterization of the Hg neighborhood charge distribution at high oxygen doping on the Hg planes. The PAC technique has been applied to investigate the effect of high oxygen pressure during the measurement. Polycrystalline HgBaCaCuO (Hg-1212) samples have been annealed at 152 bar pressurized oxygen. The influence of oxygen pressure during the experiment was then investigated by measuring the samples at atmospheric pressure and under 152 bar oxygen pressure. The present set of PAC experiments shows that at high oxygen concentrations there is a non-uniform oxygen distribution. Moreover, the Hg environment is not free from oxygen and the results hint to a new type of ordering. [ABSTRACT FROM AUTHOR]

The Perturbed Angular Correlation (PAC) technique was applied to study the yttrium local environment in YMnO multiferroic manganite. The electric field gradients (EFG) at the Y site have been measured as function of temperature, covering both ferroelectric and magnetic transitions. The results were compared with point charge model (PCM) calculations. The experimental results show two different EFG distributions for all temperatures. Only one can be directly attributed to the yttrium crystalline site in the hexagonal structure. [ABSTRACT FROM AUTHOR]

This work presents an electric field gradient and magnetic hyperfine field study, in the AgCrO multiferroic with triangular spin lattice. The temperature dependence of the electric field gradient ( efg) and magnetic hyperfine field ( mhf) at Cr site was studied at isolde via perturbed angular correlation measurements with the In probe, at room temperature and below the Néel temperature ( T ≤ 21 K) down to 12 K. The results show the presence of two distinct local environments. One axial symmetric efg with a very low mhf, and a non axially symmetric efg with a much higher one. The temperature dependences of mhf magnitude and of the angle between the mhf and the principle component of the efg are investigated. [ABSTRACT FROM AUTHOR]

A Perturbed Angular Correlation (PAC) study was performed on the % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifH.hDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGmbGaaeyyamaaBaaaleaacaqGXaGaaeylaiaabIhaaeqaaOGaae4q % aiaabsgadaWgaaWcbaGaaeiEaaqabaGccaqGnbGaaeOBaiaab+eada % WgaaWcbaGaae4maiaabUcacqaH0oazaeqaaaaa!447E! $${{La}}_{{{{1 - x}}}} {{Cd}}_{{{x}}} {{MnO}}_{{{{3 + }}}}$$ system that presents a rich variety of structural and magnetic phase transitions as a function of the oxygen content ( δ) or as a function of temperature ( T). The PAC signal at room temperature allowed the determination of the Electrical Field Gradient (EFG) parameters and to correlate them with the lattice average symmetry namely the orthorhombic ( O′ or O*) Pbnm and rhombohedral ( R) % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX!% MathType!MTEF!2!1!+-% feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX% garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz% aebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq% Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq% Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca% qGsbWaa0aaaeaacaqGZaaaaiaaboeaaaa!3A12! $${\text{R}}\overline{{\text{3}}} {\text{C}}$$ phases measured by X-ray diffraction. [ABSTRACT FROM AUTHOR]