Search results for " America"

What to avoid to succeed as an entrepreneur

2015

Abstract Entrepreneurship is a driver of economic growth and development. This study highlights the importance of entrepreneurship in emerging countries and examines entrepreneurs' characteristics in these countries. In particular, the study explains what entrepreneurs should avoid to succeed in Latin America. An empirical study analyzes factors that relate to businesses and entrepreneurs in El Salvador, one of the Latin American countries with the lowest rates of business success. In the study, business factors consist of the use of formal and informal advisory services and the degree of innovation. Variables that relate to the entrepreneur are educational attainment and the demographic va…

Using high-potential firms as the key to achieving territorial development

2016

Abstract This study examines which entrepreneurial antecedents like education, gender, motivation, and age; and environmental variables like citizen insecurity enable high-potential firms to establish themselves and act as the key to territorial development. The inclusion of the variable citizen insecurity is unusual, but several authors note how a violent context can affect entrepreneurial activity in Latin America. Insecurity generates massive expenses for entrepreneurs, who must invest to protect themselves against violence and cover the extraordinary expenses arising from this violence. The data analysis technique is fuzzy-set qualitative comparative analysis (fsQCA), a powerful techniq…

Maize based diets and possible neurobehavioural after-effects among some populations in the world

1996

Maize is a cereal particularly lacking in tryptophan, which is the precursor of serotonin, an important neurotransmitter. Altough complementary foods may eliminate tryptophan deficiency, serotonin deficiency may often continue to exist because of competition made by other Large Neutral Amino Acids (LNAA) against tryptophan for neuron access, since they use the same carrier to cross the blood-brain barrier. Thus serotonin synthesis depends on two variables: the amount of tryptophan and the trp/LNAA ratio (R). “R” is lowest for common maize, low for beans and, as a rule, for most vegetable foods, higher for meat. So, when maize is the preponderant food in the meal, the “R” value lowers and so…

Trainee research prizes from the 2019 RSNA scientific assembly and annual meeting

2020

Trainee Research Prizes from the 2019 RSNA Scientific Assembly and Annual Meeting

Volatile contents of mafic-to-intermediate magmas at San Cristóbal volcano in Nicaragua

2017

San Cristóbal volcano in northwest Nicaragua is one of the most active basaltic–andesitic stratovolcanoes of the Central American Volcanic Arc (CAVA). Here we provide novel constraints on the volcano's magmatic plumbing system, by presenting the first direct measurements of major volatile contents in mafic-to-intermediate glass inclusions from Holocene and historic-present volcanic activity. Olivine-hosted (forsterite [Fo] < 80; Fo< 80) glass inclusions from Holocene tephra layers contain moderate amounts of H2O (0.1–3.3 wt%) and S and Cl up to 2500 μg/g, and define the mafic (basaltic) endmember component. Historic-present scoriae and tephra layers exhibit more-evolved olivines (Fo69…

Contratación internacional de médicos/as latinoamericanos/as en Portugal y España

2015

A partir das experiências dos/as médicos/as latino-americanos/as que exercem a sua profissão em Portugal e em Espanha, o artigo busca comparar o recrutamento internacional dos/as médicos/as, o reconhecimento das qualificações para o exercício da Medicina e os processos de integração profissional no sistema de saúde português e espanhol. Para isso, foi utilizada uma metodologia qualitativa baseada em entrevistas em profundidade. Os resultados mostram semelhanças e divergências em cada uma destas três dimensões nos dois contextos nacionais. From the experiences of Latin American doctors who practice their profession in Portugal and Spain, the article seeks to compare the international recruit…

Mexican Americans in the New York Times : a study of proposition 187 in California

2002

Could the recent zika epidemic have been predicted?

2017

AbstractGiven knowledge at the time, the recent 2015-2016 zika virus (ZIKV) epidemic probably could not have been predicted. Without the prior knowledge of ZIKV being already present in South America, and given the lack of understanding of key epidemiologic processes and long-term records of ZIKV cases in the continent, the best related prediction was for potential risk of an Aedes-borne disease epidemic. Here we use a recently published two-vector capacity model to assess the predictability of the conditions conducive to epidemics of diseases like zika, chikungunya or dengue, transmitted by the independent or concurrent presence of Aedes aegypti and Aedes albopictus. We compare the potenti…

Mapping of Chagas disease research: analysis of publications in the period between 1940 and 2009

2011

INTRODUCTION: Publications are often used as a measure of success in research work. Chagas disease occurs in Central and Southern America. However, during the past years, the disease has been occurring outside Latin America due to migration from endemic zones. This article describes a bibliometric review of the literature on Chagas disease research indexed in PubMed during a 70-year period. METHODS: Medline was used via the PubMed online service of the U.S. National Library of Medicine from 1940 to 2009. The search strategy was: Chagas disease [MeSH] OR Trypanosoma cruzi [MeSH]. RESULTS: A total of 13,989 references were retrieved. The number of publications increased steadily over time fro…

Genomic Changes of Chagas Disease Vector, South America

2004

We analyzed the main karyologic changes that have occurred during the dispersion of Triatoma infestans, the main vector of Chagas disease. We identified two allopatric groups, named Andean and non-Andean. The Andean specimens present C-heterochromatic blocks in most of their 22 chromosomes, whereas non-Andean specimens have only 4-7 autosomes with C-banding. These heterochromatin differences are the likely cause of a striking DNA content variation (approximately 30%) between Andean and non-Andean insects. Our study, together with previous historical and genetic data, suggests that T. infestans was originally a sylvatic species, with large quantities of DNA and heterochromatin, inhabiting th…