Time filter

Source Type

VELAZQUEZ-MARTI B.,Polytechnic University of Valencia | CAZCO-LOGRONO C.,Technical University of the North, Ibarra
Experimental Agriculture | Year: 2017

The development of dendrometric methodologies could allow accurate estimation of variables associated with the crown, such as primary production (fruit and timber) and tree vigor. The aim of this work was to develop a suitable method to estimate woody biomass in plum trees (Prunus domestica L.) in Imbabura, Ecuador by using an adapted dendrometry. Form factors and regression models were defined for branch volume calculation. From this, the distribution of woody biomass in the crown tree was characterized in every stratum. Occupation Factor and regression models were obtained in order to calculate the biomass in the crown tree, which can be used to estimate the CO2 captured in its structure during its development. Regression models for calculation of whole volume of the tree and pruned biomass were directly obtained from crown diameter and crown height with R ajustated 2 of 0.74 and 0.81. The average moisture content of green material was 51%, and the average density of dry material was 0.66 ± 0.07 g cm−3. Proximate analysis of plum wood showed at 79.8 ± 9.2% volatiles and 2.1 ± 0.3% ash. Elemental analysis of the wood pointed to 46.5 ± 1.2% C, 6.1 ± 0.5% H, 46.3 ± 1.2% O, 0.6 ± 0.3% N, 0.06 ± 0.02% S and 0.02 ± 0.01% Cl. Cl, S and N contents are lower than the limits established by the standard EN 14691-part 4. With 46% of C, considering the relation 3.67 (44/12) between CO2 and C content, the CO2 sequestrated in the materials is 1.11 Mg m−3 wood material. Such method represents a tool to manage orchard resources and for assessing other parameters, such as raw materials for cultivation, fruit production, CO2 sink and waste materials (residual wood) used for energy or industry. Copyright © Cambridge University Press 2017

Rybarczyk Y.,New University of Lisbon | Rybarczyk Y.,Technological Amerindian University, Ambato | Carvalho D.,Technical University of the North, Ibarra
Advances in Intelligent Systems and Computing | Year: 2017

This research consists in studying the effect of the implementation of a biological law on the teleoperation of a mobile robot. Two experimental conditions are compared: a Manual one, in which the velocity of the robot is controlled by the human operator, and a Biological one, in which the vehicle’s speed is automatically calculated by using the 2/3 Power Law. Results show that the robot is driven faster and safer with the human-like behavior than without. The objective of the study is to propose an innovative method for the development of semi-autonomous vehicles, which is based on an anthropomorphic approach. © Springer International Publishing Switzerland 2017.

Galeas M.O.,Technical University of the North, Ibarra | Barahona A.,Technical University of the North, Ibarra | Lugo R.S.,Technical University of the North, Ibarra
Archivos Latinoamericanos de Nutricion | Year: 2017

This cross-sectional study assessed the nutritional status of 120 Ecuadorian indigenous adults Awá to determine the correlation between BMI and body fat percentage estimated by bioelectrical impedance, as well as to evaluate the diagnostic accuracy of BMI to detect excess body fat percentage in this population. Mean BMI was 23.81 ± 1.95 kg / m2 in men and 23.58 ± 1.95 kg / m2 in women, and mean body fat percentage was 11.4 ± 5.9 in men and 19.97 ± 7.19 in women. A significant positive correlation was observed between BMI and body fat percentage in men (r=0.54, p<0.01) and in women (r=0.72, p<0.01). There was also a significant positive correlation in groups of 18-40 years (r=0.79, p<0.01) and 40-59 years (r=0.49, p<0.01), while in older than 60 years the correlation was positive but not significant (r=0.50, p=0.97). There was significant correlation in the group considered healthy by fat percentage (r=0.54, p<0.001), but there was no significant correlation in under fat and over fat groups (r=0.07 p=0.57, r=0.38 p=0.31 respectively). BMI =25 kg/m2 showed a sensitivity of 90%, specificity 75% and an area under the curve of 0.88 (95% CI from 0.81 to 0,95) to detect excess body fat. In conclusion, although the use of BMI as a predictor of excess fat is justified in this population, it is necessary to conduct more studies to develop additional indicators for assessing the nutritional status of in more comprehensive way, not only focused on overweight and obesity.

PubMed | University of Turku, Technical University of the North, Ibarra, James Cook University, University of Nottingham and 46 more.
Type: Journal Article | Journal: Proceedings. Biological sciences | Year: 2016

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change.

Vossen J.H.,Wageningen University | Dezhsetan S.,University of Mohaghegh | Esselink D.,Wageningen University | Arens M.,Wageningen University | And 5 more authors.
Plant Methods | Year: 2013

Background: Molecular profiling of gene families is a versatile tool to study diversity between individual genomes in sexual crosses and germplasm. Nucleotide binding site (NBS) profiling, in particular, targets conserved nucleotide binding site-encoding sequences of resistance gene analogs (RGAs), and is widely used to identify molecular markers for disease resistance (R) genes.Results: In this study, we used NBS profiling to identify genome-wide locations of RGA clusters in the genome of potato clone RH. Positions of RGAs in the potato RH and DM genomes that were generated using profiling and genome sequencing, respectively, were compared. Largely overlapping results, but also interesting discrepancies, were found. Due to the clustering of RGAs, several parts of the genome are overexposed while others remain underexposed using NBS profiling. It is shown how the profiling of other gene families, i.e. protein kinases and different protein domain-coding sequences (i.e., TIR), can be used to achieve a better marker distribution. The power of profiling techniques is further illustrated using RGA cluster-directed profiling in a population of Solanum berthaultii. Multiple different paralogous RGAs within the Rpi-ber cluster could be genetically distinguished. Finally, an adaptation of the profiling protocol was made that allowed the parallel sequencing of profiling fragments using next generation sequencing. The types of RGAs that were tagged in this next-generation profiling approach largely overlapped with classical gel-based profiling. As a potential application of next-generation profiling, we showed how the R gene family associated with late blight resistance in the SH*RH population could be identified using a bulked segregant approach.Conclusions: In this study, we provide a comprehensive overview of previously described and novel profiling primers and their genomic targets in potato through genetic mapping and comparative genomics. Furthermore, it is shown how genome-wide or fine mapping can be pursued by choosing different sets of profiling primers. A protocol for next-generation profiling is provided and will form the basis for novel applications. Using the current overview of genomic targets, a rational choice can be made for profiling primers to be employed. © 2013 Vossen et al.; licensee BioMed Central Ltd.

Pais-Chanfrau J.M.,Technical University of the North, Ibarra | Trujillo-Toledo L.E.,University las Fuerzas Armadas
Biology and Medicine | Year: 2016

The methylotrophic yeast Pichia pastoris became an excellent and successfully expression system for therapeutics and other useful heterologous proteins at large-scale. Its capacity to reach a high-cell-densityconcentration during its fed-batch fermentations in a chemically-defined culture medium is one of the main features of this system. The standard culture medium BSM developed by Invitrogen Co. has been the most widespread used. However, it contains certain components in improper ratios that lead to precipitation of some of its components during preparation, mainly after sterilization and/or during pH adjustment. In this study, we propose a modified version of the BSM culture medium, named MBSM. These simple modifications by employing a linear optimization technique solves the precipitation problems observed on BSM and other culture media. Beside it, is rather simple, easy to prepare, and inexpensive, and it has impact positively over the environment by reducing the pollution load of the fermentation waste and also diminish the cost of the industrial scale fermentation process. By using this modified medium, were reached cell densities of 100 gDCW · L-1 and 60 gDCW · L-1 for mini-proinsulin and exo-levanase under the inducible AOX1 and the constitutive GAPDH promoters, respectively. These results allow to get vast amounts of proteins able to be used in nanoscience and other biotechnological applications. © 2016 Pais-Chanfrau JM, et al.

Canadas A.,Technical University of the North, Ibarra | Rade D.,Technical University of the North, Ibarra | Zambrano C.,Instituto Nacional Autonomo Of Investigaciones Agropecuarias
Revista Colombiana de Entomologia | Year: 2014

Field monitoring of Tephritidae populations is fundamental for a modern agricultural management of these insect pest species. Thus, it is necessary to collect data on environmental conditions and their fluctuations with the purpose of determining how they affect the distribution patterns of fruit flies in an important fruit production region like the Santa Elena peninsula. In this study the fruit fly populations were analyzed in relation to biotic and abiotic factors. To reach this objective, maps of land slope, floor texture and climatology were generated and overlapped with 694 georeferenced traps located in the four cardinal points of the Santa Elena region, in a study area of 3.466 ha. The results indicate that the minimum–maximum temperatures, relative humidity, and rainfall were the major climatic factors influencing fly populations dynamics. Soil texture did not have any influence on immature stages (larvae/pupae). Ceratitis capitata was common during the dry season and reached its peak at the end of it. It attacked both early and mid-season agricultural production in the study region. Anastrepha fraterculus, A. obliqua, A. serpentina, A. punensis, A. manihoti, A. chiclayae and A. pickeli, which were also collected, are native species widely distributed. Results highlight the importance of fruit fly management, which is the main limitation for the export of diverse fruits and vegetables produced in Ecuador. © 2014 The American Society for Cell Biology.

Palacios W.,Technical University of the North, Ibarra
Caldasia | Year: 2012

Four new tree species of Ecuador belonging to four families are described: Carapa amorphocarpa (Meliaceae) and Hasseltia crassa (Salicaceae) from the slopes of the Cerro Golondrinas, near the border with Colombia; Gloeospermum crassicarpum (Violaceae) from shared border of Colombia, Ecuador, and Peru; and Gyranthera amphibiolepis (Malvaceae) from the foothills of eastern Ecuador. Carapa amorphocarpa is distinguished easily by its thick leaflets with rounded or shortly emarginated apices and especially by its enormous amorphous fruits. Hasseltia crassa is distinguished by its large, coriaceous, thick leaves with deeply impressed venation and the inflorescence, which is relatively short and robust. Gloeospermum crassicarpum is characterized by the corolla, which is orange and apically curved, and the fruit, which has a thick mesocarp. Gyranthera amphibiolepis is characterized by the digitate leaves and the flowers, which are up to 8 cm in length, and have a staminal tube that shows the anthers in a similar arrangement to that of Ochroma (Malvaceae).

Palaciosa W.A.,Technical University of the North, Ibarra | Perezb J.,Technical University of the North, Ibarra
Acta Horticulturae | Year: 2014

Tagua is a species of palm that grows in and adjacent to wet forests along the coast of Ecuador and in the Chocó Region. The purpose of this study is to identify best management practices and regulate tagua (seed) or vegetable ivory and palm leaf (cade) harvesting. A socio-economic and ecological characterization was conducted in seven communities, four located inside Machalilla National Park and three outside. Quantitative information was gathered on the tagua populations, the forest in general, traditional harvesting practices, and on socio-economic aspects related to these practices. Each community has traditional harvesting areas, which have two harvesting seasons per year: one from August to November and another from February to April. In general, community members that own land use goodharvesting practices; however, people that come to harvest from other areas often without permission use poor practices. 100% of the people interviewed received income from tagua sales. The natural tagua population for seedlings and those under 10 cm of diameter breast height (DBH) is 436 trees/ha and 177 trees/ha above that size. There are many uses for dried tagua nuts and leaves. The proposals for good management practices for tagua nuts and palm leaves are based on local knowledge and an analysis of the plant population.

PubMed | Technical University of the North, Ibarra and University of the Balearic Islands
Type: Journal Article | Journal: Enfermeria clinica | Year: 2015

The research raises the need to increase understanding of organizational and personal factors that influence the attitude and aptitude of each professional, with respect to evidence-based clinical practice. The aim of this study is to describe the transfer of knowledge into clinical practice in hospital units in Imbabura (Ecuador) identifying the obstacles to implementing evidence-based clinical practice validated questionnaire EBPQ-19.A cross-sectional observational study was conducted in hospitals of the Ministry of Public Health of Imbabura of Ecuador took place, including a total of 281 nurses and physicians.Nurses and physicians showed positive attitudes toward evidence-based clinical practice (EBCP) and their use to support clinical decision-making. This research evidences perceptions of professionals on strategies for knowledge transfer and obstacles to carry it out. Significant differences between the perception of the use of EBCP strategies between nurses and physicians are observed. Physicians consider they use them frequently, while nurses acknowledge using them less (chi-square: 105.254, P=.018).In conclusion, we can say that these factors should be considered as necessary to improve the quality of care that is provided to users based on the best available evidence. It is necessary to start developing change interventions in this regard to remedy the current situation of clinical practice based not on evidence, but rather on experience only. Experimental studies demonstrating the effectiveness of strategies to eliminate barriers to scientific evidence-based clinical practice should be conducted.

Loading Technical University of the North, Ibarra collaborators
Loading Technical University of the North, Ibarra collaborators