Bose-Einstein Condensation on Curved Manifolds

Here we describe a weakly interacting Bose gas on a curved manifold, which is embedded in the three-dimensional Euclidean space.~To this end we start by considering a harmonic trap in the normal direction of the manifold, which confines the three-dimensional Bose gas in the vicinity of its surface.~Following the notion of dimensional reduction as outlined in [L.~Salasnich et al., Phys.~Rev.~A {\bf 65}, 043614 (2002)], we assume a large enough trap frequency so that the normal degree of freedom of the condensate wave function can be approximately integrated out. In this way we obtain an effective condensate wave function on the quasi-two-dimensional surface of the curved manifold, where the thickness of the cloud is determined self-consistently. For the particular case when the manifold is a sphere, our equilibrium results show how the chemical potential and the thickness of the cloud increase with the interaction strength.~Furthermore, we determine within a linear stability analysis the low-lying collective excitations together with their eigenfrequencies, which turn out to reveal an instability for attractive interactions.Comment: 33 pages, 6 figure

Entropy of a Turbulent Bose-Einstein Condensate

Quantum turbulence deals with the phenomenon of turbulence in quantum fluids, such as superfluid helium and trapped Bose-Einstein condensates (BECs). Although much progress has been made in understanding quantum turbulence, several fundamental questions remain to be answered. In this work, we investigated the entropy of a trapped BEC in several regimes, including equilibrium, small excitations, the onset of turbulence, and a turbulent state. We considered the time evolution when the system is perturbed and let to evolve after the external excitation is turned off. We derived an expression for the entropy consistent with the accessible experimental data, that is, using the assumption that the momentum distribution is well-known. We related the excitation amplitude to different stages of the perturbed system, and we found distinct features of the entropy in each of them. In particular, we observed a sudden increase in the entropy following the establishment of a particle cascade. We argue that entropy and related quantities can be used to investigate and characterize quantum turbulence.Comment: 14 pages, 5 figure

Momentum distribution of Vinen turbulence in trapped atomic Bose-Einstein condensates

The decay of multicharged vortices in trapped Bose-Einstein condensates may lead to a disordered vortex state consistent with the Vinen regime of turbulence, characterized by an absence of large-scale flow and an incompressible kinetic energy spectrum $E\propto k^{-1}$. In this work, we study numerically the dynamics of a three-dimensional harmonically trapped Bose-Einstein condensate excited to a Vinen regime of turbulence through the decay of two doubly-charged vortices. First, we study the momentum distribution and observe the emergence of a power-law behavior $n(k)\propto k^{-3}$ consistent with the coexistence of wave turbulence. We also study the kinetic energy and particle fluxes, which allows us to identify a direct particle cascade associated with the turbulent stage.Comment: 5 pages, 2 figure

A enxurrada de 11 de Setembro de 1813 nas freguesias de São Bartolomeu, Santa Bárbara e São Jorge das Doze Ribeiras (Terceira)

[...] As catástrofes provenientes do rigor de intempéries sempre assolaram com alguma regularidade o quotidiano das populações da ilha Terceira, espalhando a angústia e a miséria entre os moradores dos lugares afectados. A comprová-lo, em 11 de Setembro de 1813, as freguesias de S. Bartolomeu, Santa Bárbara e S. Jorge das Doze Ribeiras foram atingidas por enxurradas, em virtude de ter havido «... na serra de Santa Barbara grande enchente das ribeiras, procedida de uma tromba d’agoa que sobre ella caiu... ». Aágua transbordou das ribeiras e ramificou-se em várias correntes que percorreram grandes distâncias e causaram prejuízos consideráveis não apenas em «... casas que levou, como na gente, nos gados e campos, cujas paredes ficaram arrasadas e os cerrados areados...». [...

Ethnobotanical and ethnopharmacological study of medicinal plants used by a traditional community in Brazil's northeastern.

The aim of this research is to make a survey of the socio-environmental characteristics and the ethnobotanical study of medicinal plants used in a traditional community in the Brazilian Northeast, Alagoas. The study was made based on visits with the application of a questionnaire with questions related to the socio-economic element and on the diversity of plants used in herbal medicine. The research was made from March/2019 to February/2020, where families and interviewed plant exhibitors were interviewed for botanical identification. The studied community, which were 24 interviewees, was compiled by residents of the Quilombola community from Pau D?arco in Arapiraca city - Alagoas. Residents interviewed, 15 (62.5%) attended between 56 to 80 years, 11 interviewees about 46% were born in the community and 13 (54%) had a fundamentally incomplete nature. At the end, there were mentioned 30 plant species used for phytotherapeutic purposes, from which presents bigger usage as plants against arterial hypertension (Salvia rosmarinus Schleid), diabetes Mellitos (Croton heliotropiifolius Kunth), pain and inflammation (Alternanthera tenella Colla), present the biggest number of species in the community. The species cited are related to numerous medicinal uses, among which there will be predominant associations associated with cardiovascular and inflammatory processes. The tea is the main way of preparing plants. It is perceived that medicinal plants are only widely used by this Quilombola community of and growth of the crops in the backyard are considered a tradition. Esta pesquisa teve como objetivo realizar um levantamento das características socioambientais e estudo etnobotânico de plantas medicinais utilizadas por uma comunidade tradicional do nordeste brasileiro, Alagoas, Brasil. O estudo se deu por meio de visitas com aplicação de um questionário contendo perguntas relacionadas aos fatores socio-econômicos e sobre a diversidade das plantas utilizadas como medicinais. O trabalho foi realizado no período de março/2019 a fevereiro/2020, onde foram entrevistadas famílias e catalogadas amostras de plantas para identificação botânica. A população estudada, com 24 entrevistados, foi composta por moradores da comunidade Quilombola Pau Darco da cidade de Arapiraca - Alagoas. Dos moradores entrevistados, 15 (62,5%) apresentavam idade entre 56 e 80 anos, 11 dos entrevistados cerca de 46%, são naturais da comunidade e 13 (54%) possuíam ensino fundamental incompleto. Ao todo, foram citadas 30 espécies de plantas utilizadas para fins terapêuticos, das quais apresentam maior utilização as plantas contra a hipertensão arterial (Salvia rosmarinus Schleid), diabetes Mellitos (Croton heliotropiifolius Kunth), dor e inflamação (Alternanthera tenella Colla). As espécies citadas estão relacionadas a inúmeras utilizações medicinais, entre os quais predominaram as doenças associadas ao aparelho cardiovascular e processos inflamatórios. O chá é principal forma de preparo das plantas. Percebe-se que as plantas medicinais são amplamente utilizadas por essa comunidade quilombola e o cultivo no quintal é considerado uma tradição

Oral delivery of fish oil in oil-in-water nanoemulsion : development, colloidal stability and modulatory effect on in vivo inflammatory induction in mice

To improve the oral absorption of fish oil and test its anti-inflammatory effect, a fish oil nanoemulsion was developed using cis-4,7,10,13,16,19-docosahexaenoic fatty acid as a biomarker for oral administration. The colloidal stability tests of the fish oil nanoemulsion showed an average size of 155.44 nm ± 6.46 (4 °C); 163.04 nm ± 9.97 (25 °C) and polydispersity index 0.22 ± 0.02 (4 °C), 0.21 ± 0.02 (25 °C), indicating systems with low polydispersity and stable droplets. The fish oil nanoemulsion did not alter the cell viability of the RAW 264.7 macrophages and, at a concentration of 0.024 mg/mL, was kinetically incorporated into the cells after 18 h of contact. The nanoemulsion was maintained in the gastrointestinal region for a significantly shorter period of time (p ≤ 0.05) compared to the intake of fish oil in free form. Inflammatory tests demonstrated that nanoemulsion and fish oil showed less (p ≤ 0.05) neutrophil infiltration after 24h of sepsis induction and there was a significant reduction (p ≤ 0.05) in the volume of paw edema in female adult Balb/c mice who received the nanoemulsion diet compared to the other experimental groups (control, formalin, fish oil and sunflower oil). These results indicate that the fish oil nanoemulsion was significantly effective in the dietary conditions tested here, presenting satisfactory responses in the modulation of inflammatory disorders, demonstrating interesting and beneficial nutraceutical effects

Genetic signatures of parental contribution in black and white populations in Brazil

Two hundred and three individuals classified as white were tested for 11 single nucleotide polymorphisms plus two insertion/deletions in their Y-chromosomes. A subset of these individuals (n = 172) was also screened for sequences in the first hypervariable segment of their mitochondrial DNA (mtDNA). In addition, complementary studies were done for 11 of the 13 markers indicated above in 54 of 107 black subjects previously investigated in this southern Brazilian population. The prevalence of Y-chromosome haplogroups among whites was similar to that found in the Azores (Portugal) or Spain, but not to that of other European countries. About half of the European or African mtDNA haplogroups of these individuals were related to their places of origin, but not their Amerindian counterparts. Persons classified in these two categories of skin color and related morphological traits showed distinct genomic ancestries through the country. These findings emphasize the need to consider in Brazil, despite some general trends, a notable heterogeneity in the pattern of admixture dynamics within and between populations/groups