Quantum discrete breathers

We review recent studies about quantum discrete breathers. We describe their basic properties in comparison with their classical counterparts, and the ways they may be addressed theoretically in different quantum lattice models including either bosonic or fermionic excitations. We also review recent experimental work in the field.Comment: 49 pages, 36 figures, some corrected typos, and the section "Conclusions and outlook" was added. Chapter for a book edited by S. Keshavamurthy and P. Schlagheck with title "Dynamical Tunneling: Theory and Experiment

Periodic orbits 1-5 of quadratic polynomials on a new coordinate plane

While iterating the quadratic polynomial f_{c}(x)=x^{2}+c the degree of the iterates grows very rapidly, and therefore solving the equations corresponding to periodic orbits becomes very difficult even for periodic orbits with a low period. In this work we present a new iteration model by introducing a change of variables into an (u,v)-plane, which changes situation drastically. As an excellent example of this we can compare equations of orbits period four on (x,c)- and (u,v)-planes. In the latter case, this equation is of degree two with respect to u and it can be solved explicitly. In former case the corresponding equation ((((x^{2}+c)^{2}+c)^{2}+c)^{2}+c-x)/((x^{2}+c)^{2}+c-x)=0 is of degree 12 and it is thus much more difficult to solve

Therapeutic testing and epigenetic characterization of Friedreich Ataxia

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Friedreich ataxia (FRDA) is an autosomal recessive, neurodegenerative disorder with severely debilitating effects and no current cure. FRDA is mainly caused by the hyper-expansion of a GAA repeat present in intron 1 of the FXN gene, which results in decreased gene expression and consequently a deficiency of the mitochondrial protein frataxin. In the first instance, frataxin deficiency renders an impaired protection from oxidative stress. Antioxidant therapy with cannabinoids (CBD and THC) and CTMIO was investigated in GAA repeat FXN YAC transgenic mouse models of FRDA, but no significant improvements were detected on functional measurements such as rotarod performance and locomotor activity. Additionally such compounds failed to protect the brain of treated mice from oxidative insults. Therefore, the use of such antioxidant compounds cannot be advocated for FRDA therapy. Recent findings indicate that FXN silencing in FRDA may be mediated by repressive heterochromatin, suggesting the use of histone deacetylase inhibitors (HDACi) as FXN up-regulators. Therefore, therapy with a benzamide-type HDACi (106) was similarly investigated on the FXN YAC GAA mouse model. No significant improvements were detected by functional and histochemical analysis. However, significant changes were produced in global acetylation levels of H3 and H4 in the brain of treated mice, suggesting that the drug is capable of crossing the blood-brain barrier and producing an effect. Additionally, significant increases in frataxin expression were detected in the brain of treated mice. To identify further FRDA disease mechanisms, characterization of the FXN gene for the presence of the CCCTC-binding factor (CTCF) was also performed on FRDA patient cerebellum samples. Overall, lower levels of CTCF were detected in FRDA-associated FXN alleles, suggesting the potential involvement of CTCF in the regulation of FXN transcription

Likelihood-based Inference for Multivariate Regression Models using Synthetic Data

Likelihood-based exact inference procedures are derived for the multivariate regression model, for singly and multiply imputed synthetic data generated via Posterior Predictive Sampling (PPS), via a newly proposed sampling method, which will be called Fixed-Posterior Predictive Sampling (FPPS), and via Plug-in sampling. By contemplating the single imputation case, the new developed procedures fill the gap in the existing literature where inferential methods are only available for multiple imputation and, by being based in exact distributions, it may even be applied to cases where the sample size is small. Simulation studies compare the results obtained from all the proposed exact inferential procedures and also compare these with the results obtained from the adaptation of Reiter’s combination rule to multiply imputed synthetic datasets. An application using U.S. 2000 Current Population Survey data is discussed and measures of privacy are presented and compared among all methods

Music Festivals in the 1960s

UID/EAT/00472/2013 SFRH/BD/103718/2014The beginning of television broadcasts in Portugal in September 1956 played an important role in the Portuguese musical environment. However, the quick technical advances associated with television would eventually enable the Hertezian connection between Portugal and Spain, which led to the creation of a new space, Iberovisão. In addition to Spain’s role as a bridge between Portugal and Eurovision broadcasts, the connection between the two neighbouring countries, which began in 1960, generated a new media space for cultural exchanges, which became visible through two important música ligeira festivals: the Festival da Canção de Benidorm and the Festival Hispano- Portugués de la Cancion del Duero, among other initiatives. The fact that Portugal and Spain lived under dictatorial political regimes leads us to believe that these festivals were, in addition to important cultural experiences associated with music, a form of affirmation of the two dictatorial regimes in an increasingly democratized Western Europe. Proof of this is the Declaration of December 15th, 1960 on the Granting of Independence to Colonial Countries and Peoples of the United Nations (UN). Based on the analysis of the two mentioned music festivals, I highlight the importance that the technical novelties associated with television, linking Portugal and Spain (Iberovisão), had in the origin and development of the mentioned events, assuming them as spaces of cultural and ideological affirmation in the political context of the 1960s.publishersversionpublishe

A new Erica lusitanica Rudolphi heathland association to the Iberian south-west

As result of several field trips following doctoral research in Marianic-Monchiquensean Sector, we describe a new heathland named Lavandulo viridis-Ericetum lusitanici ass nova hoc loco (Genistion micrantho-anglicae, Rivas- Martínez 1979) as a thermomediterranean to lower mesomediterranean, upper dry to humid, schistose association. The analysis of 11 relevés, following Braun-Blanquet methodology shows the floristic identity of this new association as well as the chorological segregation of its area of occurrence. Finally, despite these communities already being relatively well known and although they are poor in species number, such heathlands show floristic singularity and own sinecology, with a large and distinct geographical area of distribution, so we emphasized its integration within Atlantic wet heaths priority habitat (⁄4020 – Annex B-I from Council Directive 92/43/EEC of 21 May 1992)

Using mobile device detection approaches to augment the accuracy of web delivery content

Recent studies of mobile Web trends show a continuous explosion of mobile-friendly content. However, the increasing number and heterogeneity of mobile devices poses several challenges for Web programmers who want to automatically get the delivery context and adapt the content to mobile devices. In this process, the devices detection phase assumes an important role where an inaccurate detection could result in a poor mobile experience for the enduser. In this paper we compare the most promising approaches for mobile device detection. Based on this study, we present an architecture for a system to detect and deliver uniform m-Learning content to students in a Higher School. We focus mainly on the devices capabilities repository manageable and accessible through an API. We detail the structure of the capabilities XML Schema that formalizes the data within the devices capabilities XML repository and the REST Web Service API for selecting the correspondent devices capabilities data according to a specific request. Finally, we validate our approach by presenting the access and usage statistics of the mobile web interface of the proposed system such as hits and new visitors, mobile platforms, average time on site and rejection rate

Validação do método analítico para a determinação da atividade antioxidante do fruto do Crataegus monogyna

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências FarmacêuticasA sustentabilidade é um conceito complexo que se pode resumir na noção de desenvolvimento económico e social, sem provocar grandes danos ao ambiente e aos recursos naturais. As plantas bravias frequentemente utilizadas nas indústrias alimentar e farmacêutica compõem uma lista consideravelmente extensa da flora nacional. No entanto, muitas dessas plantas não têm sido reconhecidas pelo seu verdadeiro mérito a nível de utilidade nutricional e/ou terapêutico. A Crataegus monogyna Jacq. é uma árvore fruteira silvestre e cujos frutos edíveis são fontes naturais de compostos fitoquímicos que apresentam efeitos terapêuticos na prevenção de muitas doenças crónicas não-transmissíveis. Os compostos fenólicos são substâncias produzidas pelo metabolismo secundário das plantas e caracterizam-se por apresentarem um anel aromático que contem pelo menos um grupo hidroxilo. Estes compostos apresentam uma elevada capacidade de ligarem-se aos radicais livres, sendo por isso, caracterizados como antioxidantes. A extração dos compostos fitoquímicos é uma das etapas mais críticas dado que a sua eficiência depende de múltiplos parâmetros, nomeadamente, o tipo de amostra, propriedades químicas dos analitos em estudo, tipo de solvente extrator, entre outros. Este estudo teve como principal objetivo avaliar a capacidade extratora dos compostos fitoquímicos (fenólicos e flavonóides) recorrendo a diferentes solventes e avaliar a atividade antioxidante dos mesmos. A quantificação dos compostos fitoquímicos e as atividades antioxidantes apresentaram valores médios significativamente diferentes (p 0,05) mediante natureza do solvente extrator. Os resultados obtidos indicam, por meio de uma abordagem fitoquímica in vitro, que o fruto do pilriteiro é uma fonte natural rica em metabolitos secundários com propriedades terapêuticas reconhecidas e que o seu uso, na indústria farmacêutica, poderá ser potenciado. Sustainability is complex concept that can be explain as the economic and social development without causing damages to the environment and the natural resources. Wild plants commonly used in the food and pharmaceutical industries make up a fairly lengthy list of the national flora. However, many of these plants have not been recognized for their true merit to the possible utility level of their nutritional and / or therapeutic effects. Crataegus monogyna Jacq. is a wild fruit tree whose fruits are edible and a natural source of phytochemical compounds that present therapeutic effects in the prevention of many chronic non-transmissible diseases. The phenolic compounds are secondary metabolites synthesized by plants, presenting an aromatic ring with at least one hydroxyl group in their chemical structure. These compounds have a high capacity to bind to free radicals and are, therefore, characterized as antioxidants. The phytochemical extraction is one of the most critical steps since the efficiency depends on multiple parameters, including, sample type, chemical properties of the analytic constituent, type of organic solvent, among others. This study pretended to evaluate the extraction capacity of phytochemicals (phenolics and flavonoids) by using different solvents and, also, evaluates the antioxidant activity. The quantification of the phenolics and flavonoids compounds and antioxidant activity showed mean values significantly different (p 0.05) considering the nature of the organic solvent. The results indicates, by means of a phytochemical in vitro approach, that the fruit of “pilriteiro” is a good natural source of secondary metabolites with known therapeutic properties and their use in the pharmaceutical industry may be enhanced