Algebraically special solutions in AdS/CFT

We investigate the AdS/CFT interpretation of the class of algebraically special solutions of Einstein gravity with a negative cosmological constant. Such solutions describe a CFT living in a 2+1 dimensional time-dependent geometry that, generically, has no isometries. The algebraically special condition implies that the expectation value of the CFT energy-momentum tensor is a local function of the boundary metric. When such a spacetime is slowly varying, the fluid/gravity approximation is valid and one can read off the values of certain higher order transport coefficients. To do this, we introduce a formalism for studying conformal, relativistic fluids in 2+1 dimensions that reduces everything to the manipulation of scalar quantities.Comment: 30 pages + appendices, 2 figures; v2: typos corrected, ref. adde

Object-oriented Programming Laws for Annotated Java Programs

Object-oriented programming laws have been proposed in the context of languages that are not combined with a behavioral interface specification language (BISL). The strong dependence between source-code and interface specifications may cause a number of difficulties when transforming programs. In this paper we introduce a set of programming laws for object-oriented languages like Java combined with the Java Modeling Language (JML). The set of laws deals with object-oriented features taking into account their specifications. Some laws deal only with features of the specification language. These laws constitute a set of small transformations for the development of more elaborate ones like refactorings

Factors related to survival in Intensive Care Unit patients with Covid-19: a study from a single center in Brazil

Introduction: Analysis of the outcome of 268 ICU patients in a single-center, as well the impact of viral infection on patients with preexisting medical conditions and how these factors affected survival and hospital stay. Methodology: Patients admitted to the ICU from March-August, 2020 were retrospectively analyzed under the same protocol at Hospital Alemão Oswaldo Cruz, São Paulo, Brazil. Several factors were considered and the results were presented using 95% confidence intervals. For statistical significance, p <0.05 was adopted. Results: Patient median age was 72 years, 64,2 years for discharged patients and 79.9 years for those deceased (p<0.001). The most common comorbidities were: systemic arterial hypertension, diabetes, thyroid disease, cardiovascular and kidney disease. Predictors of survival through univariate analysis: myalgia (p=0.001), cerebrovascular disease (p=0.002), COPD (p=0.003), dementia (p=0.000), mechanical ventilation (p=0.000), dialysis (0.000), vasopressor use (0.000), SAPS3 (0.000), lymphopenia (p=0.004), elevated D-dimer (P=0.011), time in ICU before tracheostomy (p=0.002), and performing a tracheostomy (p=0.000). The independent predictors of mortality were: advanced age (p=0.003) and tracheostomy performed in ICU (p=0.002). Discussion: COVID-19 affects usually older adults, where there already is a higher fatality rate. Acute respiratory distress syndrome is the primary cause of death and <5% of patients were reported as experiencing co-infection at admission. Conclusion: age, vasopressor use in patients with tracheostomy, and systemic coronary disease, heart failure, neoplasia, and COPD, were found to be significantly associated with COVID-19 severity

Incoherent electronic band states in Mn substituted BaFe2_{2}As2_{2}

Chemical substitution is commonly used to explore new ground states in materials, yet the role of disorder is often overlooked. In Mn-substituted BaFe$_{2}$As$_{2}$ (MnBFA), superconductivity (SC) is absent, despite being observed for nominal hole-doped phases. Instead, a glassy magnetic phase emerges, associated with the $S=5/2$ Mn local spins. In this work, we present a comprehensive investigation of the electronic structure of MnBFA using angle-resolved photoemission spectroscopy (ARPES). We find that Mn causes electron pockets to shrink, disrupting the nesting condition in MnBFA. Notably, we propose that electronic disorder, along with magnetic scattering, primarily contributes to suppressing the itinerant magnetic order in MnBFA. This finding connects the MnBFA electronic band structure properties to the glassy magnetic behavior observed in these materials and suggests that SC is absent because of the collective magnetic impurity behavior that scatters the Fe-derived excitations. Moreover, we suggest that Mn tunes MnBFA to a phase in between the correlated metal in BaFe$_{2}$As$_{2}$ and the Hund insulator phase in BaMn$_{2}$As$_{2}$.Comment: main 7 pages, 3 figures + supp 5 pages, 5 figure

Análise teórico e experimental de ligações tipo RHS/CHS com afastamento

This work presents a study of welded K joints with gap, formed by a structural steel hot rolled hollow section, having rectangular hollow sections at the chords and circular hollow sections in the others members. The study developed theoretical and numerical analyses for the joints, experimental tests in full scale prototypes. Theoretical analyses were performed using code standards for K joints. The results in terms of behavior, ultimate load and collapse mode were analyzed and compared with numerical (finite elements) and theoretical models. The theoretical analysis was carried out from the code regulations. The joints tested indicated the failure mode of Plastic failure of the chord face (mode A). The results showed that the loads using code regulations and the ones from the numerical analysis had good agreement for the K joint.Nesse trabalho, é apresentado um estudo de ligações soldadas tipo K com afastamento, constituídas de barras tubulares de aço sem costura, sendo usada seção transversal tubular retangular, no banzo, e circular, para os outros elementos. O estudo envolveu análise teórica e numérica, para as ligações, além de ensaios de protótipos, em escala real. As análises teóricas utilizaram normas de projeto, para a ligação K. Os ensaios foram realizados, em protótipos, em escala real, visando à obtenção do comportamento, da carga última e do modo de falha da ligação e à calibração com modelo numérico (elementos finitos), bem como visando a se fazer uma comparação com prescrições normativas. Essas ligações ensaiadas apresentaram, como modo de falha, a plastificação da face do banzo (modo A). Os resultados numéricos indicaram que a relação entre as cargas numéricas e as de projeto, obtidas pelas prescrições, apresenta boa correlação, para ligações K.29530

Bionomics of Culex quinquefasciatus within urban areas of Rio de Janeiro, Southeastern Brazil

OBJECTIVE: To evaluate density, parity rates, daily survival and longevity of natural populations of Culex quinquefasciatus in three neighborhoods with distinct socio-economic and infrastructure profiles. METHODS: Mosquito collections of the Culex quinquefasciatus species were performed weekly during two four month periods, from August to November 2008 (spring) and March to June 2009 (fall), in a favela (slum), a suburban area and a middle class area of Rio de Janeiro, Southeastern Brazil. Collections were performed with backpack aspirators, in 20 randomly selected houses in each area per week, during 15-20 minutes per house. Ovaries were removed from captured females and classified as initial, intermediary or final stage. Furthermore, females were dissected for determination of parity based on the condition of the tracheal system. Mosquito survival rate and longevity were estimated on a per month basis for each neighborhood. RESULTS: We collected a total of 2,062 Culex quinquefasciatus, but monthly vector density was not correlated with temperature and rainfall. We dissected the ovaries of 625 Culex quinquefasciatus, and overall, there was a higher proportion of nulliparous females during the dryer months, while gravid females were more frequent in rainy months. In the middle class neighborhood, the parity rate reached up to 93.75% with survivorship of 0.979. Lower parity and survival rates were obtained in the suburban area (as low as 36.4% parity and 0.711 daily survival). Up to 84.7% of Culex quinquefasciatus females could survive the eight day period needed to complete West Nile Virus incubation. CONCLUSIONS: The survival rate of Culex quinquefasciatus varied significantly between the neighborhoods. This suggests that vectorial capacity and disease transmission risk may vary greatly between different urban areas, which is potentially useful information for vector control programs

DESTILAÇÃO DE ÁGUA POR ENERGIA SOLAR

Vários países têm enfrentado problemas relacionados ao fornecimento de água potável e também para atender às necessidades das indústrias. Alguns destes países têm procurado soluções para obter água purificada a partir de água salgada encontrada em poços ou água do mar. O objetivo deste trabalho foi realizar um estudo sobre produtos processos tecnológicos na área de purificação de água por energia solar abrangendo documentos de patentes publicados desde a década de 1950. A China destaca-se no número de patentes e inventores. Grande parte dos processos de purificação são fundamentalmente baseados na vaporização de água através da concentração de energia solar por espelhos côncavos ou por placas metálicas com estruturas tipo estufa. O Brasil tem sete depósitos de patentes nesta área, disponíveis nas bases de dados nacionais e internacionais

Comportamento de novas progênies de sorgo forrageiro para o Semi-Árido Pernambucano

This work is related to 45 recently developed forage sorghum varieties. It aims to offer to Pernambuco Semi-Arid region farmers forage sorghum (Sorghum bicolor L.) varieties with higher yield capacity. The trials were carried out in Caruaru, São Bento do Una, Arcoverde and Serra Talhada involving nine different environments made up with combinations of years and localities. The experimental design was in randomized blocks with three replications in 1982, and without replications in 1983 and 1984. Analysis of dry matter (DM) productivity stability was also realized using the linear regression coefficient following the Eberhart & Russel Model. Progenies 467-4-2, 380-5-1, 322-1-3 and 484-1-1 showed outstandig behavior across the environments. The two first ones yielded 12.47 and 11.45 t/ha of DM and had a linear regression b = 1.03. The last two ones yielded 10.67 and 10.49 t/ha of DM and had a linear regression b = 0.90, which characterizes them as adapted to a less favorable environment. The sorghum variety IPA 7301218, previously recommended for planting in Pernambuco, had inferior performance among all other treatments. Este trabalho relata o desempenho de 45 novas progênies de sorgo forrageiro (Sorghum bicolor L.) objetivando propiciar aos produtores do Semi-Árido de Pernambuco cultivares de sorgo mais produtivas. Os testes foram conduzidos em Caruaru, São Bento do Una, Arcoverde e Serra Talhada, totalizando nove ambientes distintos, formados pelas combinações de anos e locais. O delineamento experimental foi o de blocos ao acaso, com três repetições, em 1982, e sem repetição, em 1983 e 1984. Efetuou-se, também, a análise de estabilidade da produtividade de matéria seca, pela estimativa do coeficiente de regressão linear, de acordo com o modelo proposto por Eberhart & Russel. As progênies 467-4-2, 389-5-1, 322-1-3 e 484-1-1 destacaram-se favoravelmente nas avaliações. As duas primeiras apresentaram uma produtividade média de 12,47 e 11,45 t/ha, respectivamente, de MS, e um coeficiente de regressão linear b = 1,03 que as caracterizam como estáveis. As duas últimas apresentaram uma produtividade média de 10,67 e 10,49 t/ha de MS, respectivamente, e um coeficiente de regressão linear b = 0.90, que as caracterizam como adaptadas a ambiente menos favorável. A cultivar de sorgo forrageiro IPA 7301218, previamente recomendada para plantio em Pernambuco, teve um desempenho inferior a todos os demais tratamentos.

Acute and Chronic Effects of Whole-Body Vibration on Balance, Postural Stability, and Mobility in Women With Multiple Sclerosis

The acute and chronic effects of whole-body vibration (WBV) on balance, postural stability, and mobility were evaluated in 21 women with relapsing-remitting multiple sclerosis (MS) randomly assigned to control (n = 9) or experimental (n = 12) groups. To assess acute responses, outcome variables were assessed before and immediately after a session of WBV (five 30-second bouts of vibration; frequency 30 Hz; amplitude 3 mm; 1-minute rest intervals) during their first visit (week 1) using field (Timed-Up and Go; 500-m walk; Berg Balance Scale) and laboratory tests (NeuroCom Balance Master and EquiTest System—Sensory Organization Test, Adaptation Test, Limits of Stability, Modified Clinical Test for Sensory Integration of Balance, Unilateral Stance, Tandem Walk, Step/Quick Turn). Acute responses were also measured after their fifth visit for only the Adaptation and Sensory Organization tests. For the chronic responses, participants were exposed to the WBV protocol once a week, for a total of 5 weeks, and then at week 5, were reassessed with the Adaptation and the Sensory Organization tests. Neither acute nor chronic exposure to the WBV protocols used in this study resulted in significant improvements (P > .05) in balance, postural stability, or mobility as assessed by either field or laboratory tests. However, based on promising results from other studies that have used WBV with other clinical populations, either alone or in conjunction with exercise, additional studies that increase the dose of vibration exposure, both acutely and chronically, should be conducted in patients with MS.Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) received no financial support for the research, authorship, and/or publication of this article.Ye