Two-Dimensional Electronic Structure of the GaAs(110)-Bi System

The occupied electronic structure of the GaAs(110)-Bi(1×1) monolayer system has been studied using angle-resolved photoelectron spectroscopy with a synchrotron-radiation source. The overlayer system possesses at least three detectable surface states (S’, S’’ and S’’’) with two-dimensional character. Both the state with the lowest (S’) and the state with the highest (S’’’) binding energy are clearly visible over a large portion of the (1×1) surface Brillouin zone. The intermediate state (S’’) was observed along Γ¯ X¯ ’ and also in the neighborhood of X¯. The intensity of all three states exhibits a predominantly pz-like dependence on the polarization of the synchrotron light. However, S’’’ possesses a greater component of pxy-like character than either S’ or S’’. At the zone center, S’ is situated 0.5 eV above the valence-band maximum, and it disperses downwards by ≊1.0 eV to X¯, and by ≊0.8 eV to X¯ ’. At M¯ it has its binding-energy maximum, 1.3 eV below the energetic position at Γ¯. The two-dimensional electronic structure of this system is compared with that of the closely related GaAs(110)-Sb(1×1) monolayer system and with the results of first-principles calculations

Effects of a high-fat and energy diet on ovarian gene expression in young and aged female mice.

Publicado: Proceedings of the 29th Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Gramado, RS, Brazil, August 20th to 23rd, 2015, and 31st Meeting of the European Embryo Transfer Association (AETE); Ghent, Belgium, September 11th and 12th, 2015. Abstracts

Nummular keratopathy in a patient with Hyper-IgD Syndrome

<p>Abstract</p> <p>Purpose</p> <p>To report a case of recurrent nummular keratitis in a pediatric patient with Hyperimmunoglobulinemia D syndrome.</p> <p>Methods</p> <p>A retrospective chart review.</p> <p>Results</p> <p>A 14-year-old boy with Hyperimmunoglobulinemia D syndrome (HIDS) presented with photophobia and ocular irritation concomitant with disease exacerbation. He was found on exam to have significant nummular keratitis, which responded to a short course of topical steroids. Despite acute response to local immunosuppression, the patient had several recurrent attacks and eventually developed a large corneal scar and decreased vision. After initiation of infliximab therapy his ocular sequelae improved dramatically and his vision returned to 20/20.</p> <p>Conclusion</p> <p>One possible form of end-organ damage associated with HIDS is vision threatening nummular keratopathy.</p

Ballistic Electron Emission Microscopy on CoSi2{}_2/Si(111) interfaces: band structure induced atomic-scale resolution and role of localized surface states

Applying a Keldysh Green`s function method it is shown that hot electrons injected from a STM-tip into a CoSi${}_2$/Si(111) system form a highly focused beam due to the silicide band structure. This explains the atomic resolution obtained in recent Ballistic Electron Emission Microscopy (BEEM) experiments. Localized surface states in the $(2 \times 1)$-reconstruction are found to be responsible for the also reported anticorrugation of the BEEM current. These results clearly demonstrate the importance of bulk and surface band structure effects for a detailed understanding of BEEM data.Comment: 5 pages, RevTex, 4 postscript figures, http://www.icmm.csic.es/Pandres/pedro.ht

Factors associated with unintended pregnancy in Brazil: cross-sectional results from the Birth in Brazil National Survey, 2011/2012

Background Unintended pregnancy, a pregnancy that have been either unwanted or mistimed, is a serious public health issue in Brazil. It is reported for more than half of women who gave birth in the country, but the characteristics of women who conceive unintentionally are rarely documented. The aim of this study is to analyse the prevalence and the association between unintended pregnancy and a set of sociodemographic characteristics, individual-level variables and history of obstetric outcomes. Methods Birth in Brazil is a cross-sectional study with countrywide representation that interviewed 23,894 women after birth. The information about intendedness of pregnancy was obtained after birth at the hospital and classified into three categories: intended, mistimed or unwanted. Multinomial regression analysis was used to estimate the associations between intendedness of a pregnancy, and sociodemographic and obstetric variables, calculating odds ratios and 95 % confidence intervals. All significant variables in the bivariate analysis were included in the multinomial multivariate model and the final model retaining variables that remained significant at the 5 % level. Results Unintended pregnancy was reported by 55.4 % of postpartum women. The following variables maintained positive and significant statistical associations with mistimed pregnancy: maternal age < 20 years (OR = 1.89, 95 % CI: 1.68–2.14); brown (OR = 1.15, 95 % CI: 1.04–1.27) or yellow skin color (OR = 1.56, 95 % CI: 1.05–2.32); having no partner (OR = 2.32, 95 % CI: 1.99–2.71); having no paid job (OR = 1.15, 95 % CI: 1.04–1.27); alcohol abuse with risk of alcoholism (OR = 1.25, 95 % CI: 1.04–1.50) and having had three or more births (OR = 2.01, 95 % CI: 1.63–2.47). The same factors were associated with unwanted pregnancy, though the strength of the associations was generally stronger. Women with three or more births were 14 times more likely to have an unwanted pregnancy, and complication in the previous pregnancies and preterm birth were 40 % and 19 % higher, respectively. Previous neonatal death was a protective factor for both mistimed (OR = 0.61, 95 % CI: 0.44–0.85) and unwanted pregnancy (OR = 0.44, 95 % CI: 0.34–0.57). Conclusions This study confirms findings from previous research about the influence of socioeconomic and individual risk factors on unintended pregnancy. It takes a new approach to the problem by showing the importance of previous neonatal death, preterm birth and complication during pregnancy as risk factors for unintended pregnancy

Brazilian adolescents' knowledge and beliefs about abortion methods: A school-based internet inquiry

Background: Internet surveys that draw from traditionally generated samples provide the unique conditions to engage adolescents in exploration of sensitive health topics.Methods: We examined awareness of unwanted pregnancy, abortion behaviour, methods, and attitudes toward specific legal indications for abortion via a school-based internet survey among 378 adolescents aged 12-21 years in three Rio de Janeiro public schools.Results: Forty-five percent knew peers who had undergone an abortion. Most students (66.0%) did not disclose abortion method knowledge. However, girls (aOR 4.2, 95% CI 2.4-7.2), those who had experienced their sexual debut (aOR1.76, 95% CI 1.1-3.0), and those attending a prestigious magnet school (aOR 2.7 95% CI 1.4-6.3) were more likely to report methods. Most abortion methods (79.3%) reported were ineffective, obsolete, and/or unsafe. Herbs (e.g. marijuana tea), over-the-counter medications, surgical procedures, foreign objects and blunt trauma were reported. Most techniques (85.2%) were perceived to be dangerous, including methods recommended by the World Health Organization. A majority (61.4%) supported Brazil's existing law permitting abortion in the case of rape. There was no association between gender, age, sexual debut, parental education or socioeconomic status and attitudes toward legal abortion. However, students at the magnet school supported twice as many legal indications (2.7, SE.27) suggesting a likely role of peers and/or educators in shaping abortion views.Conclusions: Abortion knowledge and attitudes are not driven simply by age, religion or class, but rather a complex interplay that includes both social spaces and gender. Prevention of abortion morbidity and mortality among adolescents requires comprehensive sexuality and reproductive health education that includes factual distinctions between safe and unsafe abortion methods