Instantons and Killing spinors

We investigate instantons on manifolds with Killing spinors and their cones. Examples of manifolds with Killing spinors include nearly Kaehler 6-manifolds, nearly parallel G_2-manifolds in dimension 7, Sasaki-Einstein manifolds, and 3-Sasakian manifolds. We construct a connection on the tangent bundle over these manifolds which solves the instanton equation, and also show that the instanton equation implies the Yang-Mills equation, despite the presence of torsion. We then construct instantons on the cones over these manifolds, and lift them to solutions of heterotic supergravity. Amongst our solutions are new instantons on even-dimensional Euclidean spaces, as well as the well-known BPST, quaternionic and octonionic instantons.Comment: 40 pages, 2 figures v2: author email addresses and affiliations adde

Many-particle entanglement with Bose--Einstein condensates

We propose a method to produce entangled states of several particles starting from a Bose-Einstein condensate. In the proposal, a single fast $\pi/2$ pulse is applied to the atoms and due to the collisional interaction, the subsequent free time evolution creates an entangled state involving all atoms in the condensate. The created entangled state is a spin-squeezed state which could be used to improve the sensitivity of atomic clocks.Comment: 4 pages. Minor modification

Stability study of a model for the Klein-Gordon equation in Kerr spacetime

The current early stage in the investigation of the stability of the Kerr metric is characterized by the study of appropriate model problems. Particularly interesting is the problem of the stability of the solutions of the Klein-Gordon equation, describing the propagation of a scalar field of mass $\mu$ in the background of a rotating black hole. Rigorous results proof the stability of the reduced, by separation in the azimuth angle in Boyer-Lindquist coordinates, field for sufficiently large masses. Some, but not all, numerical investigations find instability of the reduced field for rotational parameters $a$ extremely close to 1. Among others, the paper derives a model problem for the equation which supports the instability of the field down to $a/M \approx 0.97$.Comment: Updated version, after minor change

Qualidade de vida nas pessoas com esquizofrenia: a influência das características sociodemográficas e clínicas e da satisfação com o suporte social

Objective: To evaluate the relationship of sociodemographic and clinical characteristics and satisfaction with social support with the quality of life of schizophrenic patients. Methodology: This study included a sample of 268 participants. An interview was conducted to obtain sociodemographic and clinical data, supplemented with two assessment tools used to evaluate quality of life (World Health Organization Quality of Life instrument-Abbreviated version – WHOQOL-Bref) and satisfaction with social support (Social Support Satisfaction Scale – SSSS). Descriptive and inferential analyses were performed. Results: Most individuals were male (63.4%), with a mean age of 45.4 years, single (85.4%), living with their family (62.3%) and unemployed (90.3%). As for clinical characteristics, most had the disease for less than 20 years (50.7%), and 55.6% had at least one hospitalization within the last 5 years. Being employed and having had no hospitalization within the last 5 years were positively correlated with one or more WHOQOL-Bref domains. The results of the variables intimacy (p<0.001) and satisfaction with friends (p<0.001) were independently related to the total WHOQOL-Bref score. Conclusion: Having a job, having had no hospitalization within the last 5 years and having greater satisfaction with social support are factors that positively influence quality of life among schizophrenics. It is therefore crucial that the psychosocial rehabilitation of patients with schizophrenia take these factors into account, increasing the support network, preventing relapses and promoting occupational activities.Objetivo: Avaliar a relação entre as características sociodemográficas e clínicas e a satisfação com o suporte social com a qualidade de vida dos doentes com esquizofrenia. Métodos: A amostra do estudo é de 268 participantes. Foi realizada uma entrevista para obter os dados sociodemográficos e clínicos e aplicados dois questionários para avaliar a qualidade de vida (World Health Organization Quality of Life instrument-Abbreviated version – WHOQOL-Bref) e a satisfação com o suporte social (Escala de Satisfação com o Suporte Social – ESSS). Foram efetuadas análises descritivas e inferenciais. Resultados: A maioria dos indivíduos era do gênero masculino (63,4%), com uma média de idade de 45,4 anos, solteiros (85,4%), vivendo com a família (62,3%) e desempregados (90,3%). Relativamente às características clínicas, 50,7% tinham a doença há menos de 20 anos, e 55,6% estiveram internados pelo menos uma vez nos últimos 5 anos. Os resultados demonstraram que estar empregado e não ter sido internado nos últimos 5 anos estão positivamente relacionados com um ou mais domínios da WHOQOL-Bref. A satisfação com a intimidade (p<0,001) e a satisfação com os amigos (p<0,001) foram independentemente associados ao escore total da WHOQOL-Bref. Conclusão: Ter emprego, não ter hospitalizações nos últimos 5 anos e estar satisfeito com o suporte social são fatores que influenciam positivamente a qualidade de vida dos doentes com esquizofrenia. Por conseguinte, é crucial que esses fatores sejam levados em conta nos programas de reabilitação com o suporte social, aumentando a rede de suporte, evitando recaídas e promovendo atividades ocupacionais.publishe

Therapeutic DNA vaccine induces broad T cell responses in the gut and sustained protection from viral rebound and AIDS in SIV-infected rhesus macaques.

Immunotherapies that induce durable immune control of chronic HIV infection may eliminate the need for life-long dependence on drugs. We investigated a DNA vaccine formulated with a novel genetic adjuvant that stimulates immune responses in the blood and gut for the ability to improve therapy in rhesus macaques chronically infected with SIV. Using the SIV-macaque model for AIDS, we show that epidermal co-delivery of plasmids expressing SIV Gag, RT, Nef and Env, and the mucosal adjuvant, heat-labile E. coli enterotoxin (LT), during antiretroviral therapy (ART) induced a substantial 2-4-log fold reduction in mean virus burden in both the gut and blood when compared to unvaccinated controls and provided durable protection from viral rebound and disease progression after the drug was discontinued. This effect was associated with significant increases in IFN-γ T cell responses in both the blood and gut and SIV-specific CD8+ T cells with dual TNF-α and cytolytic effector functions in the blood. Importantly, a broader specificity in the T cell response seen in the gut, but not the blood, significantly correlated with a reduction in virus production in mucosal tissues and a lower virus burden in plasma. We conclude that immunizing with vaccines that induce immune responses in mucosal gut tissue could reduce residual viral reservoirs during drug therapy and improve long-term treatment of HIV infection in humans

A DNA-based method for studying root responses to drought in field-grown wheat genotypes

Root systems are critical for water and nutrient acquisition by crops. Current methods measuring root biomass and length are slow and labour-intensive for studying root responses to environmental stresses in the field. Here, we report the development of a method that measures changes in the root DNA concentration in soil and detects root responses to drought in controlled environment and field trials. To allow comparison of soil DNA concentrations from different wheat genotypes, we also developed a procedure for correcting genotypic differences in the copy number of the target DNA sequence. The new method eliminates the need for separation of roots from soil and permits large-scale phenotyping of root responses to drought or other environmental and disease stresses in the field.Chun Y. Huang, Haydn Kuchel, James Edwards, Sharla Hall, Boris Parent, Paul Eckermann, Herdina, Diana M. Hartley, Peter Langridge & Alan C. McKa

Expression of Aquaporin 5 (AQP5) Promotes Tumor Invasion in Human Non Small Cell Lung Cancer

The aquaporins (AQP) are water channel proteins playing a major role in transcellular and transepithelial water movement. Recently, the role of AQPs in human carcinogenesis has become an area of great interest. Here, by immunohistochemistry (IHC), we have found an expression of AQP5 protein in 35.3% (IHC-score: ≥1, 144/408) of the resected NSCLC tissue samples. Cases with AQP5-positive status (IHC-score: ≥2) displayed a higher rate of tumor recurrence than negative ones in NSCLC (54.7% vs. 35.1%, p = 0.005) and worse disease-free survival (p = 0.033; OR = 1.52; 95%CI:1.04−2.23). Further in vitro invasion assay using BEAS-2B and NIH3T3 cells stably transfected with overexpression constructs for full length wild-type AQP5 (AQP5) and its two mutants, N185D which blocks membrane trafficking and S156A which blocks phosphorylation on Ser156, showed that AQP5 induced cell invasions while both mutants did not. In BEAS-2B cells, the expression of AQP5 caused a spindle-like and fibroblastic morphologic change and losses of cell-cell contacts and cell polarity. Only cells with AQP5, not either of two mutants, exhibited a loss of epithelial cell markers and a gain of mesenchymal cell markers. In a human SH3-domains protein array, cellular extracts from BEAS-2B with AQP5 showed a robust binding activity to SH3-domains of the c-Src, Lyn, and Grap2 C-terminal. Furthermore, in immunoprecipitation assay, activated c-Src, phosphorylated on Tyr416, showed a stronger binding activity to cellular extracts from BEAS-2B with AQP5 compared with N185D or S156A mutant. Fluorescence in situ hybridization (FISH) analysis failed to show evidence of genomic amplification, suggesting AQP5 expression as a secondary event. Based on these clinical and molecular observations, we conclude that AQP5, through its phosphorylation on Ser156 and subsequent interaction with c-Src, plays an important role in NSCLC invasion and, therefore, may provide a unique opportunity for developing a novel therapeutic target as well as a prognostic marker in NSCLC