Excited states in the twisted XXZ spin chain

We compute the finite size spectrum for the spin 1/2 XXZ chain with twisted boundary conditions, for anisotropy in the regime $0< \gamma <\pi/2$, and arbitrary twist $\theta$. The string hypothesis is employed for treating complex excitations. The Bethe Ansatz equtions are solved within a coupled non-linear integral equation approach, with one equation for each type of string. The root-of-unity quantum group invariant periodic chain reduces to the XXZ_1/2 chain with a set of twist boundary conditions ($\pi/\gamma\in Z$, $\theta$ an integer multiple of $\gamma$). For this model, the restricted Hilbert space corresponds to an unitary conformal field theory, and we recover all primary states in the Kac table in terms of states with specific twist and strings.Comment: 16 pages, Latex; added discussion on quantum group invariance and arbitrary magnon numbe

Effect of vitamin D replacement on maternal and neonatal outcomes: a randomised controlled trial in pregnant women with hypovitaminosis D. A protocol

Introduction: The vitamin D recommended doses during pregnancy differ between societies. The WHO guidelines do not recommend routine prenatal supplementation, but they underscore the fact that women with the lowest levels may benefit most. The effects of routine supplementation during pregnancy on maternal and neonatal clinical outcomes have not been investigated in the Middle East, where hypovitaminosis D is prevalent. Our hypothesis is that in Middle Eastern pregnant women, a vitamin D dose of 3000?IU/day is required to reach a desirable maternal 25-hydroxyvitamin D [25(OH)D] level, and to positively impact infant bone mineral content (BMC).Methods and analysis: This is a multicentre blinded randomised controlled trial. Pregnant women presenting to the Obstetrics and Gynaecology clinics will be approached. Eligible women will be randomised to daily equivalent doses of cholecalciferol, 600?IU or 3000?IU, from 15 to 18?weeks gestation until delivery. Maternal 25(OH)D and chemistries will be assessed at study entry, during the third trimester and at delivery. Neonatal anthropometric variables and 25(OH)D level will be measured at birth, and bone and fat mass assessment by dual-energy X-ray absorptiometry scan at 1?month. A sample size of 280 pregnant women is needed to demonstrate a statistically significant difference in the proportion of women reaching a 25(OH)D level ?50?nmol/L at delivery, and a difference in infant BMC of 6 (10)g, for a 90% power and a 2.5% level of significance. The proportions of women achieving a target 25(OH)D level will be compared between the two arms, using ?2. An independent t test will be used to compare mean infant BMC between the two arms. The primary analysis is an intention-to-treat analysis of unadjusted results.Ethics and dissemination: The protocol has been approved by the Institutional Review Board at the American University of Beirut-Lebanon (IM.GEHF.22). The trial results will be published in peer-reviewed medical journals and presented at scientific conferences.Trial registration number: NCT02434380.<br/

Solving the stellar 62Ni problem with AMS

An accurate knowledge of the neutron capture cross sections of 62,63Ni is crucial since both isotopes take key positions which affect the whole reaction flow in the weak s process up to A=90. No experimental value for the 63Ni(n,gamma) cross section exists so far, and until recently the experimental values for 62Ni(n,gamma) at stellar temperatures (kT=30 keV) ranged between 12 and 37 mb. This latter discrepancy could now be solved by two activations with following AMS using the GAMS setup at the Munich tandem accelerator which are also in perfect agreement with a recent time-of-flight measurement. The resulting (preliminary) Maxwellian cross section at kT=30 keV was determined to be 30keV = 23.4 +/- 4.6 mb. Additionally, we have measured the 64Ni(gamma,n)63Ni cross section close to threshold. Photoactivations at 13.5 MeV, 11.4 MeV and 10.3 MeV were carried out with the ELBE accelerator at Forschungszentrum Dresden-Rossendorf. A first AMS measurement of the sample activated at 13.5 MeV revealed a cross section smaller by more than a factor of 2 compared to NON-SMOKER predictions.Comment: Proceedings of the 11th International Conference on Accelerator Mass Spectrometry in Rome, Sept. 14-19, 2008; to be published in Nucl. Instr. Meth.

Inverting Time-Dependent Harmonic Oscillator Potential by a Unitary Transformation and a New Class of Exactly Solvable Oscillators

A time-dependent unitary (canonical) transformation is found which maps the Hamiltonian for a harmonic oscillator with time-dependent real mass and real frequency to that of a generalized harmonic oscillator with time-dependent real mass and imaginary frequency. The latter may be reduced to an ordinary harmonic oscillator by means of another unitary (canonical) transformation. A simple analysis of the resulting system leads to the identification of a previously unknown class of exactly solvable time-dependent oscillators. Furthermore, it is shown how one can apply these results to establish a canonical equivalence between some real and imaginary frequency oscillators. In particular it is shown that a harmonic oscillator whose frequency is constant and whose mass grows linearly in time is canonically equivalent with an oscillator whose frequency changes from being real to imaginary and vice versa repeatedly.Comment: 7 pages, 1 figure include

Das CPCJ aos tribunais da relação : caracterização dos processos de promoção e proteção

O progressivo reconhecimento do lugar que as crianças e jovens ocupam na sociedade enquanto sujeitos de direitos e a importância de incentivar, desenvolver e assegurar o exercício efetivo dos mesmos, tem convocado os interventores políticos e sociais para a observância de boas práticas em matéria de infância e juventude. Mas nem sempre foi desta forma, e existirá ainda um longo caminho a percorrer no que respeita a esta temática. Neste trabalho foi feito o enquadramento da evolução dos direitos da criança até se chegar à intervenção no âmbito da Lei 147/99. Esta intervenção foi depois seguida, desde o seu início até à chegada a sede judicial, através da análise de 92 acórdãos que implicam a matéria de facto. Obtiveram-se resultados que apontam para a maior frequência da aplicabilidade das medidas de “confiança a instituição com vista a futura adoção” e “acolhimento residencial” pelos Tribunais de Família e Menores e da Relação. Também foi possível apurar que a maioria dos recursos são indeferidos pelos Tribunais de Relação. Este estudo aponta para a necessidade de intervenção precoce em matéria de promoção e protecção, para que se possam evitar muitas vezes situações remediativas que acontecem, assim como para a importância do trabalho de acompanhamento das famíliasThe progressive recognition of the place that children and young people have in society as subjects of rights and the importance of encourage, develop and secure its effective exercise, has summoned the political and social intervenors to observe good practices within childhood and youth. It hasn’t always been like this and there’s still a long way to run regarding this issue. In this report we’ve approached the children’s rights evolution until reaching the intervention under the law 147/99. This intervention has been followed since its beginning until reaching the judicial seat, through the analysis of judgements which imply this matter.Results were obtained which aim to a greater frequency of the applicability of measures related with “the trust on an institution regarding a future adoption” and “child residential reception”. Among other results, it was also possible to gather that most of the appeals are denied by Supreme Court. This study aims to the need of early intervention, which can avoid many of the fixing situations happening, as well as the importance of working with the families and families monitoring

Sistema Bayesiano de Avaliação Nutricional Via Web

A avalia&ccedil;&atilde;o nutricional &eacute; utilizada no tratamento de uma epidemia que afeta uma grande por&ccedil;&atilde;o da popula&ccedil;&atilde;o, a obesidade. Durante este processo &eacute; poss&iacute;vel identificar n&iacute;veis distintos de incerteza. O uso de t&eacute;cnicas computacionais auxilia os especialistas e os estudiosos da &aacute;rea m&eacute;dica a&nbsp;solucionarem diversas situa&ccedil;&otilde;es complexas. A t&eacute;cnica de intelig&ecirc;ncia artificial denominada Redes Bayesianas trata algumas incertezas embutidas nos diagn&oacute;sticos de avalia&ccedil;&atilde;o nutricional, o que proporciona um resultado mais pr&oacute;ximo ao racioc&iacute;nio do(s) especialista(s) envolvido(s) no desenvolvimento da base de conhecimento do sistema. Esta caracter&iacute;stica do sistema inteligente bayesiano pode ser utilizada tanto por profissionais da &aacute;rea em estudo quanto como forma de ensino. Este artigo apresenta um sistema inteligente que aplica as redes bayesianas num dom&iacute;nio de avalia&ccedil;&atilde;o nutricional.&nbsp

Resistance profile of Rhipicephalus (Boophilus) microplus to diazinon and cypermethrin and first report of sodium channel mutation - domain III S6 - T2134A, in field samples from the state of São Paulo, Brazil.

Rhipicephalus (Boophilus) microplus (Canestrini) é um dos parasitas que mais impactam a pecuária de países tropicais e subtropicais, incluindo o Brasil, com perdas em torno de US$ 3,24 bilhões por ano. Ocorrências de populações resistentes a diferentes classes de acaricidas e suas associações têm sido amplamente diagnosticadas em todo o Brasil. Para isso, bioensaios utilizando o teste de pacote larval (LPT) impregnado com cipermetrina e diazinon em diferentes concentrações foram realizados para caracterizar a resistência fenotípica (nível de resistência, RL), a resistência molecular (mutação no domínio III - S6 T2134A) e o metabolismo enzimático do diazinon e da cipermetrina em algumas populações de R. (Boophilus) microplus coletadas em diferentes regiões do estado de São Paulo. Dentre as 40 propriedades analisadas, 18 delas apresentaram fatores de resistência à cipermetrina, sendo RL I (53%) e RL II (47%). A mutação do domínio III T2134A foi encontrada pela primeira vez no Brasil, em sete fazendas. Larvas heterozigotas foram constatadas em seis delas, e larvas homozigotas resistentes em quatro. Nenhuma diferença (P>0,05) na atividade enzimática de a-esterase e a-esterase foi observada em testes com larvas vivas e mortas em uma concentração de cipermetrina de 409,6ug/cm2. Noventa por cento das propriedades apresentaram resistência ao agente ativo diazinon: RL I em 6%, RL II em 30% e RL III em 64%. Houve diferenças significativas (P<0,05) na atividade enzimática na concentração mais elevada (3,2ug/cm2) entre os grupos de larvas vivas e mortas