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PubMed | National University of Colombia, Brazilian Radiological Protection and Dosimetry Institute (IRD), Eletrobras, Hospital San Juan Of Dios and 14 more.
Type: Journal Article | Journal: Radiation protection dosimetry | Year: 2016

Internal dosimetry intercomparisons are essential for the verification of applied models and the consistency of results. To that aim, the First Regional Intercomparison was organised in 2005, and that results led to the Second Regional Intercomparison Exercise in 2013, which was organised in the frame of the RLA 9/066 and coordinated by Autoridad Regulatoria Nuclear of Argentina. Four simulated cases covering intakes of (131)I, (137)Cs and Tritium were proposed. Ninteen centres from thirteen different countries participated in this exercise. This paper analyses the participants results in this second exercise in order to test their skills and acquired knowledge, particularly in the application of the IDEAS Guidelines. It is important to highlight the increased number of countries that participated in this exercise compared with the first one and, furthermore, the improvement in the overall performance. The impact of the International Atomic Energy Agency (IAEA) Projects since 2003 has led to a significant enhancement of internal dosimetry capabilities that strengthen the radiation protection of workers.

PubMed | National Autonomous University of Nicaragua, León, University of California at Los Angeles, Hospital Metropolitano Vivian Pellas, National Autonomous University of Nicaragua, Managua and University of Miami
Type: | Journal: Stem cell research | Year: 2016

We present a series of ten patients with non-reconstructable peripheral vascular disease (PVD), secondary to arteriosclerosis (AS) and/or diabetes mellitus (DM), treated with local injection of non-expanded autologous, adipose-derived stromal vascular fraction (SVF) cells for the purposes of enhancing neovascularization and chronic wound healing. Adipose tissue was surgically harvested and processed to yield the heterogeneous SVF cells for immediate point-of-care injection. The gastrocnemius muscles and ulcers or wounds where present were locally injected with the resulting SVF. Response to treatment was evaluated both clinically based on pain-free ambulation, wound healing capacity over time and ankle/brachial index (ABI) measurements, and by imaging using MRI-based angiography. All patients exhibited clinical improvement (reduction in rest pain and claudication and improvements in ABI), with imaging signs of neovascularization in the majority (5 of 6) of patients in whom the evaluation was feasible. Similarly, 5 of 6 chronic wounds healed without further surgical intervention. This series highlights the utility of non-expanded adipose-derived heterogeneous SVF cell population processed at the point-of-care, to treat patients with end-stage PVD as an alternative to palliation or amputation.

PubMed | G Jessie F Richardson Foundation, American University of Washington, F Jessie F Richardson Foundation, National Autonomous University of Nicaragua, Managua and 3 more.
Type: | Journal: Gerontology & geriatrics education | Year: 2016

Nicaragua is a very low-income country entering a period of rapid aging with limited geriatric training for health care professionals. To help build capacity and to enhance student learning, a short-term international service-learning program was implemented in 2004 in partnership with the Jessie F. Richardson Foundation and Nicaraguan community stakeholders. Graduate and undergraduate students at Portland State University complete coursework for one term in the United States then travel to Nicaragua for about twoweeks to participate in educational, research, and service activities, primarily in group homes for older Nicaraguans. Students learn about global aging, gerontology, community development, service learning, and Nicaraguan history and culture, then apply their gerontology-related knowledge by training direct care staff, older adults and their family members, and students. The authors describe the impetus for and evolution of the program, students evaluation of the program, faculty observations on program benefits and challenges, lessons learned, and future plans.

Munoz-Antoli C.,University of Valencia | Pavon A.,National Autonomous University of Nicaragua, Managua | Marcilla A.,University of Valencia | Toledo R.,University of Valencia | Esteban J.G.,University of Valencia
Tropical Biomedicine | Year: 2011

A cross-sectional study of cryptosporidiosis was carried out in Nicaragua. The prevalence of Cryptosporidium infection was determined in 272 (110 boys and 162 girls) schoolchildren, aged between 4 to 15 years from department of Rio San Juan. The total percentage obtained for Cryptosporidium (35.7%) was one of the highest reported so far. Cryptosporidium appeared in 94.8% of multiparasitism cases. No significant statistical differences were detected in the cryptosporidiosis prevalence between loose/watery (22.2%) and soft/formed (36.7%) stool samples. No significant age and sex differences were observed. This is the first report to identify Cryptosporidium in Nicaragua at species level, providing a preliminary molecular characterization of all positive samples, such as Cryptosporidium parvum (genotype 2). The high prevalence of C. parvum suggests that animals may be potential sources of infection for human cryptosporidiosis, although C. parvum infections may have originated from humans themselves. The human health problem caused by Cryptosporidium in this region may be related to the poor human hygiene/sanitation and contamination of the environment, food, or water supplies. Continuous exposure to the parasite could have been protective against development of symptoms in the children examined.

Munoz-Antoli C.,University of Valencia | Pavon A.,National Autonomous University of Nicaragua, Managua | Marcilla A.,University of Valencia | Toledo R.,University of Valencia | Esteban J.G.,University of Valencia
Transactions of the Royal Society of Tropical Medicine and Hygiene | Year: 2014

Background: The present study was carried out to assess the prevalence of intestinal parasite infections among children in Department of Rio San Juan (Nicaragua), to explore the extent of polyparasitism, and to identify the risk factors that might favour transmission of these parasites. Methods: A coprological study of single stool specimen, collected at random from 382 children (167 boys and 215 girls) aged 2-15 years from two municipalities, and a questionnaire, concerning demographic and epidemiological data on sanitary and behavioural habits, was filled in to identify risk factors. Results: About 93% of the children presented infection. Blastocystis hominis, the most frequently protozoa, and Trichuris trichiura, Ascaris lumbricoides and hookworm, the most prevalent helminths. Polyparasitism (85.4%[326/382]), with the highest percentages detected in females (p=0.001), in the 6-11 year age group (p,0.001) and having a rural background (p,0.001). A firm relationship between any parasite and age (OR=1.2, p=0.036) and rural background (OR=0.3, p=0.027) was detected. Living in rural areas and drinking river water were also positively associated with each of the STH species detected, and walking barefoot was also associated with hookworm infection. Conclusions: Government efforts should be focused on controlling the risk factors associated with these enteroparasites, with health education programmes in rural areas of Nicaragua. © The Author 2014.

Hilmo O.,Norwegian University of Science and Technology | Gauslaa Y.,Norwegian University of Life Sciences | Rocha L.,National Autonomous University of Nicaragua, Managua | Lindmo S.,Norwegian University of Science and Technology | Holien H.,Nord-Trøndelag University College
Botany | Year: 2013

All specimens of three foliose lichens (Lobaria pulmonaria (L.) Hoffm., n = 725; Lobaria scrobiculata (Scop.) DC., n = 6613; Pseudocyphellaria crocata (L.) Vain., n = 1237) and two pendulous lichens (Alectoria sarmentosa (Ach.) Ach., n = 441; Ramalina thrausta (Ach.) Nyl., n = 990) were collected from 160 random Picea abies (L.) H. Karst. branches (2-15 m above the ground) in three spruce-dominated boreal rainforests in Norway. Maximum diameter (foliose lichens), length (pendulous lichens), and reproductive structures were quantified in each thallus. The effects of measured tree and branch variables on abundance and reproduction were tested by generalized linear mixed models with binomial errors (binomial GLMM) and zero-altered (over-dispersed) Poisson generalized linear mixed models (ZAPGLMM). Lobaria pulmonaria, P. crocata, and R. thrausta occurred predominantly in the lower canopy, whereas the remaining species were also common at higher levels. The portions of thalli producing soredia and (or) isidia were 60%, 22%, and 14% for P. crocata, L. scrobiculata, and L. pulmonaria, respectively. Isidiate and (or) sorediate L. pulmonaria thalli occurred mainly on low, dead branches, whereas sorediate L. scrobiculata and P. crocata occurred at all heights. The occurrence of small P. crocata, <5 mm, decreased by branch height and small L. scrobiculata, <5 mm, increased with branch length and decreased with tree age. Upper branches supported a significant part of the total populations of studied lichens and are, thus, important when evaluating epiphyte conservation status.

Peguero G.,Autonomous University of Barcelona | Lanuza O.R.,National Autonomous University of Nicaragua, Managua | Save R.,IRTA - Institute of Agricultural-Alimentary Research and Technology | Espelta J.M.,Autonomous University of Barcelona
Plant Ecology | Year: 2013

Secondary succession after land abandonment in tropical dry forests has been suggested to be favoured by the facilitation effects for seedling establishment exerted by pioneer trees isolated in these savannah-like landscapes. However, it has also been noticed that these pioneer species may sometimes have an encroaching effect and arrest succession for several decades. We investigated in this study whether allelopathy can play a role in limiting seedling establishment of co-occurring tree species under the canopy of Acacia pennatula by means of lab bioassays and field experiments in north-west Nicaragua. Leaf extracts of A. pennatula did not affect seed germination but reduced the general growth and especially the development of the root compartment in seedlings, shifting their biomass allocation model to a reduced root/shoot ratio. Survival of planted seedlings under the canopy of A. pennatula was about 20-30% lower than outside, and this reduction was particularly pronounced as the dry season progressed, despite the milder conditions (e. g. higher soil moisture) being experienced in the inner positions under the canopy. Altogether, our results suggest that, rather than facilitating, A. pennatula may inhibit the establishment of seedlings under its canopy probably by means of an allelopathic interference in the development of the root system with critical negative consequences for young seedlings in terms of overcoming the dry season. This article warns about overemphasizing the nucleation effect that remnant and isolated trees may have to facilitate secondary succession in these highly disturbed savannah-like tropical dry forests. © 2011 Springer Science+Business Media B.V.

Sequeira Gomez L.,National Autonomous University of Nicaragua, Managua | Escolero Fuentes O.,National Autonomous University of Mexico
Geofisica Internacional | Year: 2010

Nicaragua is being substantially affected by climate change, whose impact is to be seen in marked seasonal variations of climatic and hydrometric parameters. Rainfall has declined sharply over the last decade within a strip of land that runs parallel to the Pacific Ocean and extends from the extreme northwest of Lake Nicaragua (also known as Cocibolca) to the Departments of Madriz and Nueva Segovia and beyond the border with Honduras. Droughts and water shortages have changed the way of life of local inhabitants along the strip, which includes the Malacatoya sub-basin. Shallow aquifers and surface water levels have been notably reduced. This has increased the need to seek new water sources in the sub-basin from a flow-systems viewpoint, applying hydro-geological, geophysical and hydro-geochemical techniques to create a conceptual model of how the systems operate. This article describes the application of 10 Continuous Vertical Electrical Soundings (CVES) and nine Vertical Electrical Soundings (VES), accompanied by a geological evaluation. Taken together, these techniques permit the identification and characterization - in terms of space and depth - of the aquifer formations present in three sub-areas of the sub-basin. Geophysical results indicate that the thickest aquifers were to be encountered in the Río Malacatoya and Las Banderas quaternary units (unconfined aquifers). In these units, the flow is through porous media. In Teustepe, in the Río Grande de Matagalpa, Cerro Oluma, La Libertad and Santa Lucía tertiary units, the flow is through fractured media (semi-confined aquifers).

Rivera C.,Lund University | Rivera C.,National Autonomous University of Nicaragua, Managua | Wamsler C.,Lund University
International Journal of Disaster Risk Reduction | Year: 2014

The integration of risk reduction and climate change adaptation has become an urgent task in addressing increasing urban risk more effectively and efficiently. This paper analyses the extent to which climate change adaptation is integrated into the policies and regulatory frameworks that guide urban risk reduction in Nicaragua, and discusses related progress. The results reveal significant progress in integrating climate change adaptation into the policy and regulatory frameworks of the three relatively new fields of (a) disaster risk reduction, (b) environmental management and (c) urban planning. They show that differences in the degree of integration relate to the development and updates to policy instruments in each field, and the extent to which they are related to the implementation of international climate change agreements. Although initially climate change adaptation integration was focused on the protection of natural resources in general, and food production in particular, since 2008 authorities have shown increasing interest in a more comprehensive and integrated approach. Nevertheless, the integration of climate change adaptation into disaster risk reduction and urban planning still lags behind the advances made in the environmental management field. It is concluded that in order to achieve greater and more coherent integration of CCA and, ultimately, improve the way climate-related risks is dealt with, urban authorities need to systematically review current policies and regulations to assess the synergies and gaps. This requires inter-sectoral and participative work with the actors concerned at national and local level, as well as the establishment of related monitoring and learning mechanisms. © 2014 Elsevier Ltd.

Calderon H.,National Autonomous University of Nicaragua, Managua | Uhlenbrook S.,Technical University of Delft
Hydrological Sciences Journal | Year: 2016

The water balance dynamics and runoff components of a tropical forested catchment (46 km2) on the southwestern Pacific coast of Nicaragua were studied combining hydrometry, geological characterization and hydrochemical and isotopic tracers (three-component hydrograph separation). The climatic water balance was estimated for 2010/11, 2011/12 and 2012/13 with net values of 811 mm year-1, 782 mm year-1 and –447 mm year-1, respectively. Runoff components were studied at different spatial and temporal scales, demonstrating that different sources and temporal contributions are controlled by dominant landscape elements and antecedent rainfall. In forested sub-catchments, permeable soils, stratigraphy and steep slopes favour subsurface stormflow generation contributing 50% and 53% to total discharge. At catchment scale, landscape elements such as smooth slopes, wide valleys, deeper soils and water table allow groundwater recharge during rainfall events. Groundwater dominates the hydrograph (50% of total discharge) under dry prior conditions. However, low soil infiltration capacity generates a larger surface runoff component (42%) under wet prior conditions which dominates total discharge. Our results show that forested areas are important to reduce surface runoff and thus soil degradation, which is relevant for the design of water management plans.EDITOR D. KoutsoyiannisASSOCIATE EDITOR D. Gerten © 2016 IAHS

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