Variability of Microcirculation Detected by Blood Pulsation Imaging

Alexei Kamshilin (2013, [Artículo])

The non-invasive assessment of blood flow is invaluable for the diagnostic and monitoring treatment of numerous vascular and neurological diseases. We developed a non-invasive and non-contact method of blood pulsation imaging capable of visualizing and monitoring of the two-dimensional distribution of two key parameters of peripheral blood flow: the blood pulsation amplitude and blood pulsation phase. The method is based on the photoplethysmographic imaging in the reflection mode. In contrast with previous imaging systems we use new algorithm for data processing which allows two dimensional mapping of blood pulsations in large object's areas after every cardiac cycle. In our study we carried out the occlusion test of the arm and found (i) the extensive variability of 2D-distribution of blood pulsation amplitude from one cardiac cycle to another, and (ii) existence of the adjacent spots to which the blood is asynchronously supplied. These observations show that the method can be used for studying of the multicomponent regulation of peripheral blood circulation. The proposed technique is technologically simple and cost-effective, which makes it applicable for monitoring the peripheral microcirculation in clinical settings for example, in diagnostics or testing the efficiency of new medicines. © 2013 Kamshilin et al.

algorithm, article, blood analysis, heart cycle, human, human experiment, image analysis, imaging system, male, microcirculation, peripheral circulation, photoelectric plethysmography, process development, Algorithms, Diagnostic Imaging, Diagnostic T CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS ANÁLISIS NUMÉRICO ANÁLISIS NUMÉRICO

Complex traits and candidate genes: estimation of genetic variance components across multiple genetic architectures

GIOVANNY COVARRUBIAS-PAZARAN Hans-Peter Piepho (2023, [Artículo])

Average Semivariance Linear Mixed Model Variance Component Estimation Polygenic Inheritance Oligogenic Inheritance Mendelian Inheritance CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MENDELISM GENETIC VARIANCE GENOME-WIDE ASSOCIATION STUDIES PHENOTYPES CHROMOSOME MAPPING

Big data, small explanatory and predictive power: Lessons from random forest modeling of on-farm yield variability and implications for data-driven agronomy

Martin van Ittersum (2023, [Artículo])

Context: Collection and analysis of large volumes of on-farm production data are widely seen as key to understanding yield variability among farmers and improving resource-use efficiency. Objective: The aim of this study was to assess the performance of statistical and machine learning methods to explain and predict crop yield across thousands of farmers’ fields in contrasting farming systems worldwide. Methods: A large database of 10,940 field-year combinations from three countries in different stages of agricultural intensification was analyzed. Random effects models were used to partition crop yield variability and random forest models were used to explain and predict crop yield within a cross-validation scheme with data re-sampling over space and time. Results: Yield variability in relative terms was smallest for wheat and barley in the Netherlands and for wheat in Ethiopia, intermediate for rice in the Philippines, and greatest for maize in Ethiopia. Random forest models comprising a total of 87 variables explained a maximum of 65 % of cereal yield variability in the Netherlands and less than 45 % of cereal yield variability in Ethiopia and in the Philippines. Crop management related variables were important to explain and predict cereal yields in Ethiopia, while predictive (i.e., known before the growing season) climatic variables and explanatory (i.e., known during or after the growing season) climatic variables were most important to explain and predict cereal yield variability in the Philippines and in the Netherlands, respectively. Finally, model cross-validation for regions or years not seen during model training reduced the R2 considerably for most crop x country combinations, while for wheat in the Netherlands this was model dependent. Conclusion: Big data from farmers’ fields is useful to explain on-farm yield variability to some extent, but not to predict it across time and space. Significance: The results call for moderate expectations towards big data and machine learning in agronomic studies, particularly for smallholder farms in the tropics where model performance was poorest independently of the variables considered and the cross-validation scheme used.

Model Accuracy Model Precision Linear Mixed Models CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MACHINE LEARNING SUSTAINABLE INTENSIFICATION BIG DATA YIELDS MODELS AGRONOMY

Development of a thermoelectric test for electrical contactors

PABLO OROZCO CORRAL FRANCISCO JAVIER IBARRA VILLEGAS NOE VILLA VILLASEÑOR (2023, [Artículo])

In the economic model in which we develop, there is a dependence on the means of transport that every day is increasing and due to the importance of electrification in the issue of efficient and clean transportation, has caused the need for companies supplying components for automotive manufacturers to evolve and develop new technologies to stay ahead of the needs of their customers being in full evolution towards electrified transport. This evolution extends not only to manufacturing but to the test methods that currently exist, since automotive standards require suppliers to test in laboratory, the components they sell to their customers to ensure their correct operation.

Electrical contactors Powered thermal cycle endurance Busbars Electrification industry INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Remedies for the Inconsistences in the Times of Execution of the Unsorted Database Search Algorithm within the Wave Approach

Manuel Ávila Aoki José Benito Elizalde Salas (2017, [Artículo])

The typical semiclassical wave version of the unsorted database search algorithm based on a system of coupled simple harmonic oscillators does not consider an important ingredient of Grovers original algorithm as it is quantum entanglement. The role of entanglement in the wave version of the unsorted database search algorithm is explored and contradictions with the time of execution of Grovers algorithm are found. We remedy the contradictions by employing two arguments, one of them qualitative and the other quantitative. For the qualitative argument we employ the probabilistic nature of a legitimate quantum algorithm and remedy the above inconsistence. Within the quantitative argument we identify a parameter in the wave version of the unsorted database search algorithm which is related to entanglement. The contradiction with the time of execution of Grovers algorithm is solved by choosing an appropriate values of such a parameter which incorporates entanglement to the wave version of the unsorted database search algorithm. The utility of the present arguments are evident if the wave version of the unsorted data base search algorithm is experimentally implemented through a system of N quantum dots with a harmonic oscillator potential as a confinement potential for each of the quantum dots. Each of the above N vibrating quantum dots must be coupled to an extra single vibrating quantum dot which entangles to all of them. In order to obtain optimal results, the coupling constants of the mentioned quantum dots should be adjusted in the way described in the present work.

Computación Unsorted database search Grover algorithm wave entanglement queries time Computación Unsorted database search Grover algorithm wave entanglement queries time INGENIERÍA Y TECNOLOGÍA

Remineralización de agua osmotizada mediante un contactor de calcita de flujo continuo ascendente

IVAN EMMANUEL VILLEGAS MENDOZA Martín Piña Soberanis ANGELICA JULIETA ALVILLO RIVERA CARLOS DAVID SILVA LUNA (2020, [Artículo])

DOI: 10.24850/j-tyca-2020-03-08

En este trabajo se evaluó la influencia de la velocidad de flujo, el tiempo de contacto y pH en un proceso de remineralización de agua osmotizada mediante un contactor piloto de calcita a flujo continuo, para la producción de agua potable. Se utilizó agua procedente de una planta desaladora de agua de mar en México, la cual carece de postratamiento (remineralización). Las pruebas experimentales se llevaron a cabo mediante el diseño y la construcción de un contactor de calcita de altura variable y ajuste de pH del influente con la adición de ácido sulfúrico. Los rangos de estudio evaluados fueron los siguientes: velocidad de flujo de 4-8 m h-1; tiempo de residencia hidráulico de 10-30 min, y pH de 3 a 6. Se implementó un diseño experimental 2k, en el que la variable de respuesta fue el índice de saturación de Langelier. Los resultados indicaron que de los tres parámetros de diseño evaluados el único que tuvo un efecto estadísticamente significativo fue el pH del influente, siendo el óptimo igual a tres. La calidad del agua remineralizada cumplió con la regulación israelí de contenido mineral para agua potable. Los resultados mostraron la conveniencia de diseñar contactores de calcita con velocidad de flujo de 8 m h-1 y 10 minutos de tiempo de residencia hidráulico, con el objetivo de disminuir los costos de inversión. Estas condiciones permiten diseñar contactores más compactos sin incidir en la eficiencia del proceso.

Remineralización Agua osmotizada Contactores de calcita CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Unsupervised segmentation and clustering time series approach to Southern Africa rainfall regime changes

Lovemore  Chipindu Walter Mupangwa Isaiah Nyagumbo Mainassara Zaman-Allah (2023, [Artículo])

Autoregressive Integrated Moving Average Facebook Prophet Hidden Markov Model Regression Regression with Hidden Logistic Process CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA COASTAL AREAS SEMIARID ZONES SUBHUMID ZONES RAINFALL CLIMATE CHANGE

Agro-morphological characterization and estimation of genetic parameters of spring maize hybrids in the inner plains of Far-West Nepal

Sandesh Thapa Darbin Joshi (2022, [Artículo])

Heat Resilient Maize Phenotypic Coefficient of Variation Heritable Traits CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA GENETIC PARAMETERS MAIZE HYBRIDS

Does access to improved grain storage technology increase farmers' welfare? Experimental evidence from maize farming in Ethiopia

Hugo De Groote Bart Minten (2024, [Artículo])

Seasonal price variability for cereals is two to three times higher in Africa than on the international reference market. Seasonality is even more pronounced when access to appropriate storage and opportunities for price arbitrage are limited. As smallholder farmers typically sell their production after harvest, when prices are low, this leads to lower incomes as well as higher food insecurity during the lean season, when prices are high. One solution to reduce seasonal stress is the use of improved storage technologies. Using data from a randomised controlled trial, in a major maize-growing region of Western Ethiopia, we study the impact of hermetic bags, a technology that protects stored grain against insect pests, so that the grain can be stored longer. Despite considerable price seasonality—maize prices in the lean season are 36% higher than after harvesting—we find no evidence that hermetic bags improve welfare, except that access to these bags allowed for a marginally longer storage period of maize intended for sale by 2 weeks. But this did not translate into measurable welfare gains as we found no changes in any of our welfare outcome indicators. This ‘near-null’ effect is due to the fact that maize storage losses in our study region are relatively lower than previous studies suggested—around 10% of the quantity stored—likely because of the widespread use of an alternative to protect maize during storage, for example a cheap but highly toxic fumigant. These findings are important for policies that seek to promote improved storage technologies in these settings.

Hermetic Storage Randomised Controlled Trial CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA STORAGE PILOT FARMS SEASONALITY WELFARE MAIZE

Preliminary dissection of grain yield and related traits at differential nitrogen levels in diverse pre-breeding wheat germplasm through association mapping

Achla Sharma Juan Burgueño Prashant Vikram Nitika Sandhu Satinder Kaur Parveen Chhuneja (2023, [Artículo])

Plant Nitrogen Use Efficiency Pre-Breeding Lines Genome-Wide Association Study Marker Trait Association CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA WHEAT PRE-BREEDING BREEDING LINES NITROGEN LANDRACES GENETIC MARKERS