Transition on the entropic elasticity of DNA induced by intercalating molecules

We use optical tweezers to perform stretching experiments on DNA molecules when interacting with the drugs daunomycin and ethidium bromide, which intercalate the DNA molecule. These experiments are performed in the low-force regime from zero up to 2 pN. Our results show that the persistence length of the DNA-drug complexes increases strongly as the drug concentration increases up to some critical value. Above this critical value, the persistence length decreases abruptly and remains practically constant for larger drug concentrations. The contour length of the molecules increases monotonically and saturates as drugs concentration increases. Measured in- tercalants critical concentrations for the persistence length transition coincide with reported values for the helix-coil transition of DNA-drug complexes, obtained from sedimentation experiments.Comment: This experimental article shows and discuss a transition observed in the persistence length of DNA molecules when studied as a function of some intercalating drug concentrations, like daunomycin and ethidium bromide. It has 15 pages and 4 figures. The article presented here is in preprint forma

Costs and Returns Analysis for South Carolina Shrimp Trawlers

This document provides an explanation on how shrimp trawler owners/operators can analyze the effects of changing costs and ex-vessel prices on the profitability of operating a shrimp trawler. An Excel spreadsheet is provided with sample boat costs and revenues. The spreadsheet allows the trawler owner/operator to enter costs and revenues data for their own vessel. This can be used to estimate average costs of landing a pound of shrimp by the vessel owner/operator and the profit (loss) per pound of landed shrimp. As input costs vary for key items like fuel, ice, BRDS, etc, the trawler owner can estimate the impact of these input costs on the total average cost of landing a pound of shrimp. Similarly, as the ex-vessel (landed) price for a pound of shrimp changes, the vessel owner/operator can estimate the impact of these price changes on the profitability of operating the trawler.Resource /Energy Economics and Policy,

Fundamental Oscillation Periods of the Interlayer Exchange Coupling beyond the RKKY Approximation

A general method for obtaining the oscillation periods of the interlayer exchange coupling is presented. It is shown that it is possible for the coupling to oscillate with additional periods beyond the ones predicted by the RKKY theory. The relation between the oscillation periods and the spacer Fermi surface is clarified, showing that non-RKKY periods do not bear a direct correspondence with the Fermi surface. The interesting case of a FCC(110) structure is investigated, unmistakably proving the existence and relevance of non-RKKY oscillations. The general conditions for the occurrence of non-RKKY oscillations are also presented.Comment: 34 pages, 10 figures ; to appear in J. Phys.: Condens. Mat

Upper bound for the conductivity of nanotube networks

Films composed of nanotube networks have their conductivities regulated by the junction resistances formed between tubes. Conductivity values are enhanced by lower junction resistances but should reach a maximum that is limited by the network morphology. By considering ideal ballistic-like contacts between nanotubes we use the Kubo formalism to calculate the upper bound for the conductivity of such films and show how it depends on the nanotube concentration as well as on their aspect ratio. Highest measured conductivities reported so far are approaching this limiting value, suggesting that further progress lies with nanowires other than nanotubes.Comment: 3 pages, 1 figure. Minor changes. Accepted for publication in Applied Physics Letter

Lifestyles and surveillance of sexual and reproductive women’s health

Abstract: Background: The epidemic increase of diseases is closely related to lifestyle changes. The low adhesion to breast self-examination and cervical cytology hinders prevention and early diagnosis during the asymptomatic state of two silent diseases, with nonspecific symptoms that are a major cause of death by cancer in the Portuguese female population. Objectives: To analyze the influence of sociodemographic variables and lifestyles in the surveillance of sexual and reproductive health of Portuguese women. Methods: Quantitative, non-experimental, correlational and cross-sectional study, conducted with a non-probabilistic convenience sample of 522 women aged between 18 and 67 years old, who applied the questionnaires about Breast self-examination, Knowledge about cervical cancer and the Inventory "My Lifestyle" (Ribeiro, 1993. Results: The average age of women is 38.89 years old. Women aged 31-37 years old (28.6%), Portuguese (99.1%), cohabiting with a partner and / or child (74.0%), with an active employment status (67 5%), residing in urban areas (55.8%) with higher education and attending family planning consultations have better lifestyles, without statistical significance (F = 0.016, p = 0.899). Conclusions: Healthy behaviors and lifestyles are crucial to good overall health. Adhesion to surveillance of sexual and reproductive women’s health is influenced by several factors, including the place of residence, employment status and lifestyles. These variables must be considered by health professionals when planning periodic screenings.info:eu-repo/semantics/publishedVersio

Modeling long memory in the EU stock market: evidence from the STOXX 50 returns

This paper examines the persistence behaviour of STOXX 50 returns. To this end, we estimated the GARCH, IGARCH and FIGARCH models based on a data set comprising the daily returns from January 5th, 1987 to December 27th, 2013. The results show that the long-memory in the volatility returns constitutes an intrinsic and empirically significant characteristic of the data and are, therefore, in consonance with previous evidence on the subject. Moreover, our findings reveal that the FIGARCH is the best model to capture linear dependence in the conditional variance of the STOXX 50 returns as given by the information criteri

Physics Beyond the Standard Model: Focusing on the Muon Anomaly

We present a model based on the implication of an exceptional E_{6}-GUT symmetry for the anomalous magnetic moment of the muon. We follow a particular chain of breakings with Higgses in the 78 and 351 representations. We analyse the radiative correction contributions to the muon mass and the effects of the breaking of the so-called Weinberg symmetry. We also estimate the range of values of the parameters of our model.Comment: 14 RevTeX pages, 5 figure