Volume Stabilization and the Origin of the Inflaton Shift Symmetry in String Theory

The main problem of inflation in string theory is finding the models with a flat potential, consistent with stabilization of the volume of the compactified space. This can be achieved in the theories where the potential has (an approximate) shift symmetry in the inflaton direction. We will identify a class of models where the shift symmetry uniquely follows from the underlying mathematical structure of the theory. It is related to the symmetry properties of the corresponding coset space and the period matrix of special geometry, which shows how the gauge coupling depends on the volume and the position of the branes. In particular, for type IIB string theory on K3xT^2/Z with D3 or D7 moduli belonging to vector multiplets, the shift symmetry is a part of SO(2,2+n) symmetry of the coset space [SU(1,1)/ U(1)]x[SO(2,2+n)/(SO(2)x SO(2+n)]. The absence of a prepotential, specific for the stringy version of supergravity, plays a prominent role in this construction, which may provide a viable mechanism for the accelerated expansion and inflation in the early universe.Comment: 12 page

Simple Detection of Large InDeLS by DHPLC: The ACE Gene as a Model

Insertion-deletion polymorphism (InDeL) is the second most frequent type of genetic variation in the human genome. For the detection of large InDeLs, researchers usually resort to either PCR gel analysis or RFLP, but these are time consuming and dependent on human interpretation. Therefore, a more efficient method for genotyping this kind of genetic variation is needed. In this report, we describe a method that can detect large InDeLs by DHPLC (denaturating high-performance liquid chromatography) using the angiotensin-converting enzyme (ACE) gene I/D polymorphism as a model. The InDeL targeted in this study is characterized by a 288 bp Alu element insertion (I). We used DHPLC at nondenaturating conditions to analyze the PCR product with a flow through the chromatographic column under two different gradients based on the differences between D and I sequences. The analysis described is quick and easy, making this technique a suitable and efficient means for DHPLC users to screen InDeLs in genetic epidemiological studies

Phosphorus priming influence on different quality of wheat cv. “Pardela” and “Gralha Azul” seeds

The seed priming allows the beginning of the metabolic processes necessary for the germination. Phosphorus is a macronutrient necessary for the growth and development of seedlings, since it participates in the structural components cell like the nucleic acid molecules. The objective was to evaluate the effect of priming and priming with phosphorus (P) on the physiological quality of wheat seeds with different levels of vigor. For the experiment, three lots of wheat seeds of Pardela cultivar, with different levels of vigor i.e. high, medium and low were used. The effect of priming with water and priming with different potential levels of phosphorus was evaluated: 0 (control), 0.10 %, 0.20 %, 0.30 %, 0.40 % and 0.50 % P. The first germination count, percentage of germination, abnormal seedlings, root and shoot length, and dry mass of the seedlings were determined. For the priming with water, the data were submitted to analysis of variance and the means compared by the Tukey test. In the study of the effect of the different concentrations of phosphorus, a variance and regression analysis was carried out, following the completely randomized design, in a factorial scheme 3x6. The Priming in water had significantly influenced all treatments, independently of the seeds vigor levels, increases in the percentage of normal seedlings obtained in the first count and also in the percentage of germination of the low and medium vigor lots, and the seedlings primed in water had significantly larger shoot length in the three different lots. Regarding the different concentrations of phosphorus, significant differences were observed only in the first count of the germination, which decreased with the increase of the phosphorus concentration and the length of the aerial part, which presented an inverse behavior, increasing with the highest levels of phosphorus. Significant interaction between the different vigor levels and phosphorus concentrations was observed only for the root length variable, where concave, linear and convex trends were observed for the high, low and medium vigor lots, respectively. Phosphorus solutions had the optimum role as priming source in promoting seed emergence and root development irrespective of quality seed

ENRAIZAMENTO DE ESTACAS DE Jasminum polyanthum TRATADAS COM ÁCIDO INDOLBUTÍRICO

Jasmim dos poetas (Jasminum polyanthum) é uma espécie ornamental muito utilizada no paisagismo. Porém, poucas pesquisas têm sido desenvolvidas sobre a eficiência de sua propagação vegetativa. Este trabalho teve como objetivo avaliar o enraizamento de estacas caulinares com 8 cm de comprimento de Jasminum polyanthum, tratadas com diferentes concentrações de ácido indolbutírico (IBA) veiculadas em talco e em solução hidroalcoólica, nas concentrações de 0, 1000, 1500 e 3000 mg L-1 ou mg Kg-1 de IBA. Após os tratamentos, as estacas foram plantadas em tubetes contendo vermiculita de granulometria média e mantidas em casa de vegetação com nebulização intermitente por 54 dias. As variáveis analisadas foram: porcentagem de estacas enraizadas, número de raízes formadas por estaca, comprimento de raízes formadas por estaca, porcentagem de estacas com calos, porcentagem de estacas vivas e porcentagem de estacas mortas. Não houve diferença significativa entre os diversos tratamentos para as variáveis estacas com calos, comprimento de raízes e número de raízes por estaca. Com relação ao enraizamento, a ausência da aplicação de IBA em solução ou talco (testemunha) apresentou resultados satisfatórios na porcentagem de estacas enraizadas (80%), comprimento de raízes (3,46 e 3,66 cm respectivamente) e número de raízes por estaca (5,55 e 4,95 respectivamente), sendo dispensável a aplicação de IBA para promover o enraizamento nesta espécie

Cor das bagas e do suco da uva 'Isabel' tratada com ácido abscísico em diferentes fases de maturação

The objective of this work was to evaluate the effect of (S)‑cis‑abscisic acid (S‑ABA) application at different ripening stages, in increasing phenolic compounds and color of berry and juice of 'Isabel' grape (Vitis labrusca). The evaluated treatments were: control, without S‑ABA application; 400 mg L‑1 S‑ABA applied 7 days before veraison (DBV) + 400 mg L‑1 S‑ABA at 35 days after first application (DAFA); 400 mg L‑1 S‑ABA applied at veraison (V) + 400 mg L‑1 S‑ABA at 35 DAFA; and 400 mg L‑1 S‑ABA applied 7 days after veraison (DAV) + 400 mg L‑1 S‑ABA at 35 DAFA. There was no difference among treatments regarding the physical characteristics of berries and clusters, as well as total polyphenols in berry and juice. However, there was an increase in total anthocyanins in berry and juice with S‑ABA application. Colorimetric variables indicated the increase in color of berry treated with S‑ABA. Juices produced from grapes treated with S-ABA were more appreciated by tasters. The treatments with 400 mg L‑1 S‑ABA applied 7 days before, during, or 7 days after veraison, combined with an additional application 35 days after the first one, increment total anthocyanin concentration and color of berry and juice of 'Isabel' grape, with better juice acceptance, without affecting total polyphenol concentration.O objetivo deste trabalho foi avaliar o efeito da aplicação do (S)‑cis‑ácido abscísico (S‑ABA) em diferentes fases de maturação, no incremento de compostos fenólicos e na cor das bagas e do suco de uva 'Isabel' (Vitis labrusca). Os tratamentos avaliados foram: testemunha, sem aplicação de S‑ABA; 400 mg L‑1 de S‑ABA aplicados 7 dias antes do “véraison” (DAV) + 400 mg L‑1 de S‑ABA aos 35 dias após a primeira aplicação (DAPA); 400 mg L‑1 de S‑ABA aplicados no “véraison” (V) + 400 mg L‑1 de S‑ABA aos 35 DAPA; e 400 mg L‑1 de S‑ABA aplicados 7 dias após o “véraison” (DAV) + 400 mg L‑1 de S‑ABA aos 35 DAPA. Não houve diferença entre os tratamentos para as características físicas das bagas e dos cachos, bem como para os compostos fenólicos totais das bagas e do suco. Contudo, houve incremento de antocianinas totais da baga e do suco com a aplicação de S‑ABA. As variáveis colorimétricas indicaram aumento da cor das bagas quando estas foram tratadas com S‑ABA. Os sucos elaborados com uvas tratadas com S‑ABA foram mais apreciados pelos provadores. Os tratamentos com 400 mg L‑1 de S‑ABA aplicados 7 dias antes, durante ou 7 dias após o “véraison”, associados à uma segunda aplicação 35 dias após a primeira, promovem o incremento da concentração de antocianinas totais e da intensidade da cor das bagas e do suco da uva 'Isabel', com melhor aceitação do suco, sem afetar a concentração de polifenóis totais

Update of D3/D7-Brane Inflation on K3 x T^2/Z_2

We update the D3/D7-brane inflation model on K3 x T^2/Z_2 with branes and fluxes. For this purpose, we study the low energy theory including g_s corrections to the gaugino condensate superpotential that stabilizes the K3 volume modulus. The gauge kinetic function is verified to become holomorphic when the original N=2 supersymmetry is spontaneously broken to N=1 by bulk fluxes. From the underlying classical N=2 supergravity, the theory inherits a shift symmetry which provides the inflaton with a naturally flat potential. We analyze the fate of this shift symmetry after the inclusion of quantum corrections. The field range of the inflaton is found to depend significantly on the complex structure of the torus but is independent of its volume. This allows for a large kinematical field range for the inflaton. Furthermore, we show that the D3/D7 model may lead to a realization of the recent CMB fit by Hindmarsh et al. with an 11% contribution from cosmic strings and a spectral index close to n_s=1. On the other hand, by a slight change of the parameters of the model one can strongly suppress the cosmic string contribution and reduce the spectral index n_s to fit the WMAP5 data in the absence of cosmic strings. We also demonstrate that the inclusion of quantum corrections allows for a regime of eternal D3/D7 inflation.Comment: LaTeX2e, 55 pages + appendices, 8 figures; v3: added appendix F and a note at the end of the conclusions in order to clarify the relation of our results to the recent work by Burgess et al. (arXiv:0811.1503

Uso do etefon e épocas de aplicação do ácido abscísico para melhorar a cor da uva de mesa 'Rubi'

The objective of this work was to evaluate the effect of ethephon and of abscisic acid (ABA) application timing on the color of 'Rubi' Table grape. Eight treatments were evaluated: control, without application; ethephon 500 mg L-1 applied seven days after veraison (7 DAV); and two concentrations of ABA (200 and 400 mg L-1) arranged with three application timings at 7 DAV, at 15 days before harvest (DBH), and at 7 DAV + 15 DBH. ABA does not modify physical‑chemical characteristics of the cluster and improves the color of grapes, especially when applied twice (7 DAV + 15 DBH) at the concentration of 400 mg L-1.O objetivo deste trabalho foi avaliar o efeito do etefon e de épocas de aplicação do ácido abscísico (ABA) na cor da uva de mesa 'Rubi'. Oito tratamentos foram avaliados: controle, sem aplicação; etefon 500 mg L-1, aplicado sete dias após o início da maturação (7 DAIM); e duas concentrações de ABA (200 e 400 mg L-1) arranjadas em três épocas de aplicação, aos 7 DAIM, aos 15 dias antes da colheita (DAC) e aos 7 DAIM + 15 DAC. O ABA não altera as características físico‑químicas dos cachos e melhora a cor das uvas, especialmente quando aplicado duas vezes (7 DAIM + 15 DAC), à concentração de 400 mg L-1

Longevidade pós-colheita da uva sem sementes 'BRS Vitória' submetida a armazenamento a frio e à aplicação de acibenzolar-S-metil

The objective of this work was to evaluate cold storage periods and postharvest longevity of the seedless table grape 'BRS Vitória' subjected to the application of the disease-resistance inducer acibenzolar-S-methyl (ASM). Bunches were treated or not with 1% ASM, placed individually in plastic clamshell trays and stored in a cold chamber at 2±1ºC, at a high relative humidity, for three periods (30, 45, and 60 days), followed by a 5-day period of shelf life in plastic clamshells, at 22±2ºC. After each storage period, gray mold (Botrytis cinerea) incidence was evaluated, and the physicochemical analysis was performed. A completely randomized design, with four replicates, was used in two 2x3 factorial arrangements: one evaluating ASM application and cold storage periods; and another, ASM and cold storage + shelf-life periods. ASM did not change the physicochemical characteristics of the bunches, and the incidence of gray mold was lower than 1% in all treatments. Water loss from bunches increased with storage periods. Even without ASM application, 'BRS Vitória' grape can preserve its postharvest quality for up to 60 days of cold storage, plus five days of shelf life in plastic clamshells.O objetivo deste trabalho foi avaliar períodos de armazenamento em câmara fria e longevidade pós-colheita da uva apirena 'BRS Vitória', submetida à aplicação do indutor de resistência a doenças acibenzolar-S-metil (ASM). Os cachos foram tratados, ou não, com ASM a 1%, individualizados em bandejas de plástico e mantidos em câmara fria a 2±1ºC e à alta umidade relativa por três períodos (30, 45 e 60 dias), seguidos por cinco dias de avaliação da vida de prateleira, a 22±2ºC. Após cada período de armazenamento, avaliou-se a incidência de mofo-cinzento (Botrytis cinerea), e realizaram-se as análises físico-químicas dos cachos. Utilizou-se o delineamento completamente casualizado, com quatro repetições, em dois arranjos fatoriais 2x3: um com avaliação de ASM e períodos de armazenamento em câmara fria; e outro, de ASM e períodos de armazenamento em câmara fria + vida de prateleira. O ASM não alterou as características físico-químicas dos cachos, e a incidência de mofo-cinzento foi inferior a 1% em todos os tratamentos. A perda de água dos cachos aumentou com os períodos de armazenamento. Mesmo sem a aplicação de ASM, a uva 'BRS Vitória' pode manter sua qualidade pós-colheita por até 60 dias de armazenamento em câmara fria, além de mais cinco dias de vida de prateleira em bandejas de plástico

Telehealth effectiveness for pre-exposure prophylaxis delivery in Brazilian public services : the Combine! Study

Introduction Pre-exposure prophylaxis (PrEP) delivery based on user needs can enhance PrEP access and impact. We examined whether telehealth for daily oral PrEP delivery could change the indicators of care related to prophylactic use in five Brazilian public HIV clinics (testing centres, outpatient clinics and infectious disease hospitals). Methods Between July 2019 and December 2020, clients on PrEP for at least 6 months could transition to telehealth or stay with in-person follow-up. Clients were clinically monitored until June 2021. A desktop or mobile application was developed, comprising three asynchronous consultations and one annual in-person consultation visit. Predictors influencing telehealth preference and care outcomes were examined. The analysis encompassed intent-to-treat (first choice) and adjustments for sexual practices, schooling, age, duration of PrEP use and PrEP status during the choice period. Results Of 470 users, 52% chose telehealth, with the adjusted odds ratio (aOR) increasing over time for PrEP use (aOR for 25–months of use: 4.90; 95% CI: 1.32–18.25), having discontinued PrEP at the time of the choice (aOR: 2.91; 95% CI: 1.40–6.06) and having health insurance (aOR: 1.91; 95% CI: 1.24–2.94) and decreasing for those who reported higher-risk behaviour (aOR for unprotected anal sex: 0.51; 95% CI: 0.29–0.88). After an average follow-up period of 1.6 years (95% CI: 1.5–1.7), the risk of discontinuing PrEP (not having the medication for more than 90 days) was 34% lower with telehealth (adjusted hazard ratio: 0.66; 95% CI: 0.45–0.97). When adjusted by mixed linear regression, no differences in adherence (measured by mean medication possession rate) were found between in-person and telehealth (p = 0.486) or at pre- and post-telehealth follow-ups (p = 0.245). Sexually transmitted infections increased between the pre-follow-up and post-follow-up choices and were not associated with in-person or telehealth (p = 0.528). No HIV infections were observed. Conclusions Our findings indicate that telehealth for PrEP delivery can enhance service rationalization and reinforce the prevention cascade. This approach reduces prophylaxis interruptions and is mainly preferred by individuals with lower demands for healthcare services