Growth patterns and scaling laws governing AIDS epidemic in Brazilian cities

Brazil holds approximately 1/3 of population living infected with AIDS (acquired immunodeficiency syndrome) in Central and South Americas, and it was also the first developing country to implement a large-scale control and intervention program against AIDS epidemic. In this scenario, we investigate the temporal evolution and current status of the AIDS epidemic in Brazil. Specifically, we analyze records of annual absolute frequency of cases for more than 5000 cities for the first 33 years of the infection in Brazil. We found that (i) the annual absolute frequencies exhibit a logistic-type growth with an exponential regime in the first few years of the AIDS spreading; (ii) the actual reproduction number decaying as a power law; (iii) the distribution of the annual absolute frequencies among cities decays with a power law behavior; (iv) the annual absolute frequencies and the number of inhabitants have an allometric relationship; (v) the temporal evolution of the annual absolute frequencies have different profile depending on the average annual absolute frequencies in the cities. These findings yield a general quantitative description of the AIDS infection dynamics in Brazil since the beginning. They also provide clues about the effectiveness of treatment and control programs against the infection, that has had a different impact depending on the number of inhabitants of cities. In this framework, our results give insights into the overall dynamics of AIDS epidemic, which may contribute to select empirically accurate models.Comment: 12 pages, 6 figure

Scaling laws and universality in the choice of election candidates

Nowadays there is an increasing interest of physicists in finding regularities related to social phenomena. This interest is clearly motivated by applications that a statistical mechanical description of the human behavior may have in our society. By using this framework, we address this work to cover an open question related to elections: the choice of elections candidates (candidature process). Our analysis reveals that, apart from the social motivations, this system displays features of traditional out-of-equilibrium physical phenomena such as scale-free statistics and universality. Basically, we found a non-linear (power law) mean correspondence between the number of candidates and the size of the electorate (number of voters), and also that this choice has a multiplicative underlying process (lognormal behavior). The universality of our findings is supported by data from 16 elections from 5 countries. In addition, we show that aspects of network scale-free can be connected to this universal behavior.Comment: Accepted for publication in EP

NGC 2782: a merger remnant with young stars in its gaseous tidal tail

We have searched for young star-forming regions around the merger remnant NGC 2782. By using GALEX FUV and NUV imaging and HI data we found seven UV sources, located at distances greater than 26 kpc from the center of NGC 2782, and coinciding with its western HI tidal tail. These regions were resolved in several smaller systems when Gemini/GMOS r-band images were used. We compared the observed colors to stellar population synthesis models and we found that these objects have ages of ~1 to 11 Myr and masses ranging from 10^3.9 to 10^4.6 Msun. By using Gemini/GMOS spectroscopic data we confirm memberships and derive high metallicities for three of the young regions in the tail (12+log(O/H)=8.74\pm0.20, 8.81\pm0.20 and 8.78\pm0.20). These metallicities are similar to the value presented by the nuclear region of NGC 2782 and also similar to the value presented for an object located close to the main body of NGC 2782. The high metallicities measured for the star-forming regions in the gaseous tidal tail of NGC 2782 could be explained if they were formed out of highly enriched gas which was once expelled from the center of the merging galaxies when the system collided. An additional possibility is that the tail has been a nursery of a few generations of young stellar systems which ultimately polluted this medium with metals, further enriching the already pre-enriched gas ejected to the tail when the galaxies collided.Comment: 11 pages, 5 figures. Accepted for publication in MNRA

The Integrity of Women in Re-making a Nation: The Case of Guinea-Bissau

This article both acknowledges and celebrates the role of women in re-making the nation of Guinea-Bissau. A gendered perspective and historical and multi-scalar framing demonstrates that women have played integral roles in nation-building over time and space in Guinea-Bissau. How have the women of Guinea-Bissau fashioned their agency? Where are the new forms of agency for women in Guinea-Bissau? An examination of nation-building shows the foundational roles of women, unique aspects of innovative economic enterprise before, during, and after the colonial period, and contemporary political efforts by women toward the production of a successful and inclusive country. Gender has opened unique opportunities in Guinea-Bissau toward the promotion of nationhood; gender is also experiencing a restriction of socio-political opportunities for women contemporarily that needs to be checked. Theories of African feminisms and intersectionality help explain this phenomenon. No analysis of community (re)building and maintenance is complete without incorporating the integrity of women

Internacionalização Acelerada de Empresas de Base Tecnológica: o Caso das Born Globals Brasileiras

The born global phenomenon has been made apparent, mainly in high technology sectors, which requires new theoretical understandings about the role of nascent and small international companies. This article analyzes the relationship between a company’s external environment in its country of origin, internal organizational factors and the factors relating to how some technology-based firms (TBFs) internationalize. A survey was applied to Brazilian TBFs. At the end of the data collection period, the first database generated 214 responses. Out of these, 85 (39.7%) were obtained from companies involved in some kind of business abroad. However, only 54 questionnaires were considered valid for this research. The data were analyzed using logistic regression statistical techniques. The results show that external factors influence the internationalization of TBFs more as compared to internal factors. Integration in the value chain and an entrepreneur’s ability to manage internationally are the factors that best distinguish the internationalization of born-global TBFs. Thus, this paper contributes to the discussion of the internationalization process of born-globals and TBFs, filling the gap regarding the importance of external, internal and entrepreneurial factors in these companies’ internationalization processes