Disjoint nonclassical hydrocarbons have very unstable lowest-lying singlet states: a PM3 study

Earlier workers have suggested that disjoint hydrocarbons have nearly-degenerate lowest-lying singlet and triplet states while non-disjoint (or joint) hydrocarbons should be ground-state triplets. PM3 results for an appropriate selection of alternant hydrocarbons are inconsistent with that generalization: disjoint, nonclassical, alternant hydrocarbons show the strongest predilection for triplet ground states.

The photodynamic and non-photodynamic actions of porphyrins

Porphyrias are a family of inherited diseases, each associated with a partial defect in one of the enzymes of the heme biosynthetic pathway. In six of the eight porphyrias described, the main clinical manifestation is skin photosensitivity brought about by the action of light on porphyrins, which are deposited in the upper epidermal layer of the skin. Porphyrins absorb light energy intensively in the UV region, and to a lesser extent in the long visible bands, resulting in transitions to excited electronic states. The excited porphyrin may react directly with biological structures (type I reactions) or with molecular oxygen, generating excited singlet oxygen (type II reactions). Besides this well-known photodynamic action of porphyrins, a novel light-independent effect of porphyrins has been described. Irradiation of enzymes in the presence of porphyrins mainly induces type I reactions, although type II reactions could also occur, further increasing the direct non-photodynamic effect of porphyrins on proteins and macromolecules. Conformational changes of protein structure are induced by porphyrins in the dark or under UV light, resulting in reduced enzyme activity and increased proteolytic susceptibility. The effect of porphyrins depends not only on their physico-chemical properties but also on the specific site on the protein on which they act. Porphyrin action alters the functionality of the enzymes of the heme biosynthetic pathway exacerbating the metabolic deficiencies in porphyrias. Light energy absorption by porphyrins results in the generation of oxygen reactive species, overcoming the protective cellular mechanisms and leading to molecular, cell and tissue damage, thus amplifying the porphyric picture.

Mao's steps in Monroe's backyard: towards a United States-China hegemonic struggle in Latin America?

Contrary to what could be expected given the United States' historical hegemony of Latin America, growing Chinese influence in this region has not led to a dispute between China and the US. Despite activism of hard-line groups in the United States, both parties have faced the issue with noticeable pragmatism. This attitude could be explained by three variables: the US political negligence towards Latin America in the Post-Cold War, the focus of Sino-Latin American relations on economic rather than geopolitical or ideological affairs, and the scanty relevance of the region in the top priorities of overall Washington-Beijing relations.

Discourses of cyberspace securitization in Brazil and in the United States

Abstract This paper uses the framework of the Copenhagen School to understand the process of securitization of cyberspace, exploring how something in such sphere becomes a threat. Seeking to contribute to the debate, this study analyses the securitization discourses of Brazil and of the United States from Hansen and Nissenbaum's (2009) theorization about the existence of a specific sector for cybersecurity. To comprehend the securitization of cyberspace in these terms allows not only to identify distinct levels of securitization, but also to capture the dynamics of cyber threats, distinguishing them from those existent in other sectors, as well as to trace distinctions between tendencies of securitization and militarization.

Forty Years of the United Nations General Assembly Resolution 3379 (XXX) on Zionism and Racism: the Brazilian Vote as an instance of United States - Brazil Relations

Abstract In 1975, Brazil voted in favor of the United Nations General Assembly resolution 3379 (XXX), equating Zionism with a form of racism. Focusing on the decision-making process of president Ernesto Geisel's (1974-1979) foreign policy, "responsible pragmatism", this article discusses how the ultimate decision to vote in favor of resolution was taken taking into account mainly US-Brazil relationship.

The European Union and the Member States: two different perceptions of border

Abstract In this article we analyze two different perceptions of border inside Europe. On the one hand, we have the perception idealized by the European Union as an international organization, which believes that states benefit more from cooperation and dilution of borders in a common space than from keeping its borders as a symbol of its sovereignty. On the other hand, we have the European member states, taken individually, with particular interests and goals that, given the threat of illegal immigration, which is currently felt in the large-scale Europe, adopt a realistic perception of the border, and look at each territory as a space that needs protection from external threats. Following this argument, we reason that the current construction of walls in several European countries reflects the rebirth of a realistic perception of the border, and this is one more challenge for Europe regarding its unity and solidarity. Is this the end of the Schengen Agreement? What is going to happen to the European project if each state unilaterally adopts a strategy to deal with illegal immigration and refugees that are coming to Europe? Can immigration lead to a retrocession of the EU idealist significance of border?

Composite synthetic hydroxyapatite 30%, in two physical states, as dermal filler

The aim of this study was to evaluate the response to the implantation of synthetic hydroxyapatite 30% (HAP-91®) in different physical states as dermal filler. Eighteen New Zealand rabbits were used, distributed randomly into two equal groups and then divided into three groups according to the postoperative period at 8, 21 and 49 days. One mL of HAP-91®, fluid and viscous, was implanted in the subcutaneous tissue, 1 cm proximal to the cranial crest of the right scapula. The thickness of the skin was measured before and after implantation and for the following 15 days. Pain sensitivity assessment was conducted, assigning the following scores: 0 - when the animal allowed the touch of the implant area and expressed no signs of pain; 1 - when the animal allowed the touch, but pain reaction occurred, like increase of the respiratory rate or attempt to escape; 2 - when the animal did not allow the touch to the implanted area. At 8, 21 and 49 days, biopsy of the implanted area was performed. No difference was observed between the thickness of the skin (p>0.05) and all animals received a score 0 for soreness. Histological analysis did not reveal any obvious inflammatory process, showing a predominance of mononuclear cells in samples of eight days and tissue organization around the biomaterial with a tendency to encapsulation. The results indicate that HAP-91®, both viscous and fluid, is biocompatible and suitable for dermal filling.

Sample surveys via electronic mail: a comprehensive perspective

Although postal questionnaires, personal interviewing, and telephone interviewing are the main methods of survey-based research, there is an increasing use of e-mail as a data collection medium. However, little, if any, published Western research in general and that of Turkish in particular have investigated e-mail survey technique from pure survey research perspective. Attempting to develop a framework to assess e-mail as a data collection mean, the purpose of this study is to explore e-mail-based questionnaire technique from complementary angles. To this goal, sample representativeness, data quality, response rates, and advantages and disadvantages of e-mail surveying are discussed.

Electronic government policies in Brazil: context, ICT management and outcomes

The State Reform processes combined with the emergence and use of Information and Communication Technology (ICT) originated electronic government policies and initiatives in Brazil. This paper dwells on Brazilian e-government by investigating the institutional design it assumed in the state's public sphere, and how it contributed to outcomes related to e-gov possibilities. The analyses were carried out under an interpretativist perspective by making use of Institutional Theory. From the analyses of interviews with relevant actors in the public sphere, such as state secretaries and presidents of public ICT companies, conclusions point towards low institutionalization of e-gov policies. The institutional design of Brazilian e-gov limits the use of ICT to provide integrated public services, to amplify participation and transparency, and to improve public policies management.

Current trends in the global tourism industry: evidence from the United States

Tourism is one of the largest U.S. industries, serving millions of international and domestic tourists yearly. Tourists visit the U.S. to see natural wonders, cities, historic landmarks, and entertainment venues. Americans seek similar attractions as well as recreation and vacation areas. Tourism competes in the global market, so it is important to understand current trends in the U.S. travel industry. Therefore, this article offers insight into important trends and suggests strategies for policy makers involved in the travel and tourism industry.

Sensitivity analysis for unmeasured confounders using an electronic spreadsheet

In studies assessing the effects of a given exposure variable and a specific outcome of interest, confusion may arise from the mistaken impression that the exposure variable is producing the outcome of interest, when in fact the observed effect is due to an existing confounder. However, quantitative techniques are rarely used to determine the potential influence of unmeasured confounders. Sensitivity analysis is a statistical technique that allows to quantitatively measuring the impact of an unmeasured confounding variable on the association of interest that is being assessed. The purpose of this study was to make it feasible to apply two sensitivity analysis methods available in the literature, developed by Rosenbaum and Greenland, using an electronic spreadsheet. Thus, it can be easier for researchers to include this quantitative tool in the set of procedures that have been commonly used in the stage of result validation.

Monoclonal antibody to serotype 17 of Neisseria meningitidis and their prevalence in Brazilian States

Neisseria meningitidis are gram-negative diplococci responsible for cases of meningococcal disease all over the world. The epidemic potential of N. meningitidis serogroup B and C is clearly a function of their serotype antigens more than of their capsular polysaccharides. Until recently, hiperimmune sera were used to detect typing antigens on the bacteria. The advent of monoclonal antibodies (MAbs) offered the opportunity to eliminate many of the cross-reactions and have improved the accuracy and reproducibility of meningococcal serotyping. We have produced a MAb to the outer membrane protein of the already existent serotype 17 that have been detected by the use of hiperimmune rabbit sera. The prevalence of this serotype epitope is low in the Brazilian strains. By using the MAb 17 we could not decrease the percentage of nontypeable serogroup C strains. However, there were a decreasing in nontypeable strains to 13% into serogroup B strains and to 25% into the other serogroups.

REACTIONAL STATES IN MULTIBACILLARY HANSEN DISEASE PATIENTS DURING MULTIDRUG THERAPY

It is well known that reactions are commonplace occurrences during the course of leprosy disease. Stigmatization may even be attributable to reactions which are also responsible for the worsening of neural lesions. A cohort of 162 newly-diagnosed baciloscopically positive patients from the Leprosy Care Outpatient Clinic of the Oswaldo Cruz Foundation (FIOCRUZ) was selected for this study. While 46% of the multibacillary (MB) patients submitted to the 24 fixed-dose multidrug therapy (MDT) regimen suffered reactions during treatment, it was found that all MBs were susceptible and that constant attention and care were required at all times. Fourteen per cent were classified as BB, 52% as BL, and 33% as LL. None of the variables under study, such as, sex, age, clinical form, length of illness, length of dermatological lesions, baciloscopic index (BI), or degree of disability proved to be associate with reaction among the patients studied. Reversal Reaction (RR) occurred in 45%, and Erythema Nodosum Leprosum (ENL) occurred in 55%. Among BB patients who developed reactions (15 patients), 93% presented RR; while among the LL patients who developed reactions (34 patients), 91% presented ENL. Likewise, ENL was very frequent among those with disseminate lesions, while RR was most often observed in patients with segmentary lesions. RR was also most likely to occur during the initial months of treatment. It was demonstrated that the recurrence rate of ENL was significantly higher than that of RR. Neither grade of disability nor BI was shown to be associated with RR and ENL reaction. However, the RR rate was significantly higher among patients showing BI < 3, while ENL predominated among those patients with BI > 3.