Morphological and chromatographie investigation on the species of the series conicibaccata of the genus solanum.

Maestría en CienciasMaestrí

Agroecological entrepreneurship, public support, and sustainable development: The case of rural Yucatan (Mexico)

This paper offers an approach to Yucatecan social reality in terms of entrepreneurship and the process of creating companies dedicated to the production and/or commercialization of agroecological products, considering its contribution to sustainable rural development. The key actors’ perspective towards the existence of policies that favor land sustainability, assist in the development of rural areas and their population, and support these business initiatives is also presented. Likewise, it illustrates the small entrepreneurs’ standpoint on the role of public institutions in promoting wealth generation and sustainable development in lower growth areas, such as the state of Yucatan, in Mexico. A qualitative methodology was used for this research, based on in-depth interviews with a group of businessmen and-women from the region. The main results give a pessimistic view of institutional concern regarding both production and consumption of agroecological products and, therefore, the promotion of these enterprises for the socioeconomic development of Yucatan. From these findings, we detect: (a) A policy of scarce support for this type of production, due to political priorities; (b) inadequate management that prevents the consolidation of certain structures needed to support agroecological enterprises; (c) a lack of confidence in the Yucatecan government, which does not promote or support a social network of collaboration between agroecological producers and marketers; (d) a difficulty in undertaking agroecological enterprises because of social and cultural norms and poor environmental awareness among the population; (e) significant training deficiencies among entrepreneurs in agroecological agriculture; (f) absence of adequate distribution channels for agroecological products; and (g) excessive bureaucratic obstacles through laws that hinder entrepreneurial processes

A flexible framework for real-time thermal-aware schedulers using timed continuous petri nets

This work presents TCPN-ThermalSim, a software tool for testing Real-Time Thermal-Aware Schedulers1. This framework consists of four main modules. The first one helps the user to define the problem: Task set with periods, deadlines and worst case execution times in CPU cycles, along with the CPU characteristics, temperature and energy consumption. The second module is the Kernel simulation, which builds up a global simulation model according to the configuration module. In the third module, the user selects the scheduler algorithm. Finally the last module allows the execution of the simulation and present the results. The framework encompasses two modes: Manual and automatic. In manual mode the simulator uses the task set data provided in the first section. In automatic mode the task set is generated by parameterizing the integrated UUniFast algorithm

Study of association between Pre-Senile cataracts and the polymorphisms rs2228000 in XPC and rs1042522 in p53 in Spanish population

To determine if the presence of certain polymorphisms in the DNA repair gene XPC and the apoptosis inductor gene p53 is associated with pre-senile cataract development. Methods We have performed a retrospective study over three groups of patients. The group with presenile cataract formed by 72 patients younger than 55 with cataract surgery. The group with senile cataract formed by 101 patients older than 55 with cataract surgery. The group without cataract was formed by 42 subjects older than 55 without lens opacities. We analyzed the presence of SNP rs2228000 from XPC and rs1042522 from p53; and the relationship between risk factors such as smoking, alcohol intake, hypertension or diabetes. Results The comparison of the genotype distribution in XPC, within the different groups, did not show any statistically significant association in any of our analysis (p>0, 05). The comparison of the genotype distribution in p53 within the different groups did not show any statistically significant association (p>0, 05); except for the comparison between the pre-senile cataract group and the group with senile cataract where the genotype Pro/Pro (C/C) in the recessive inheritance model showed a higher risk for developing pre-senile cataract (p = 0, 031; OR = 1.04-15.97). This association decreased when we performed the analysis adjusting by the studied risk factors (p = 0.056). Conclusions Allelic variants in the gene XPC are not associated with an increased risk for developing pre-senile cataract. The presence of the genotype Pro/Pro in p53 might be associated with a major risk for developing pre-senile cataract

Diagnostic ability of multifocal electroretinogram in early multiple sclerosis using a new signal analysis method

Purpose To determine if a novel analysis method will increase the diagnostic value of the multifocal electroretinogram (mfERG) in diagnosing early-stage multiple sclerosis (MS). Methods We studied the mfERG signals of OD (Oculus Dexter) eyes of fifteen patients diagnosed with early-stage MS (in all cases < 12 months) and without a history of optic neuritis (ON) (F: M = 11:4), and those of six controls (F:M = 3:3). We obtained values of amplitude and latency of N1 and P1 waves, and a method to assess normalized root-mean-square error (FNRMSE) between model signals and mfERG recordings was used. Responses of each eye were analysed at a global level, and by rings, quadrants and hemispheres. AUC (area under the ROC curve) is used as discriminant factor. Results The standard method of analysis obtains further discrimination between controls and MS in ring R3 (AUC = 0.82), analysing N1 waves amplitudes. In all of the retina analysis regions, FNRMSE value shows a greater discriminating power than the standard method. The highest AUC value (AUC = 0.91) was in the superior temporal quadrant. Conclusion By analysing mfERG recordings and contrasting them with those of healthy controls it is possible to detect early-stage MS in patients without a previous history of ON

Computer-aided diagnosis of multiple sclerosis using a support vector machine and optical coherence tomography features

The purpose of this paper is to evaluate the feasibility of diagnosing multiple sclerosis (MS) using optical coherence tomography (OCT) data and a support vector machine (SVM) as an automatic classifier. Forty-eight MS patients without symptoms of optic neuritis and forty-eight healthy control subjects were selected. Swept-source optical coherence tomography (SS-OCT) was performed using a DRI (deep-range imaging) Triton OCT device (Topcon Corp., Tokyo, Japan). Mean values (right and left eye) for macular thickness (retinal and choroidal layers) and peripapillary area (retinal nerve fibre layer, retinal, ganglion cell layer—GCL, and choroidal layers) were compared between both groups. Based on the analysis of the area under the receiver operator characteristic curve (AUC), the 3 variables with the greatest discriminant capacity were selected to form the feature vector. A SVM was used as an automatic classifier, obtaining the confusion matrix using leave-one-out cross-validation. Classification performance was assessed with Matthew’s correlation coefficient (MCC) and the AUCCLASSIFIER. The most discriminant variables were found to be the total GCL++ thickness (between inner limiting membrane to inner nuclear layer boundaries), evaluated in the peripapillary area and macular retina thickness in the nasal quadrant of the outer and inner rings. Using the SVM classifier, we obtained the following values: MCC = 0.81, sensitivity = 0.89, specificity = 0.92, accuracy = 0.91, and AUCCLASSIFIER = 0.97. Our findings suggest that it is possible to classify control subjects and MS patients without previous optic neuritis by applying machine-learning techniques to study the structural neurodegeneration in the retina

In-planta transient transformation of avocado (Persea americana) by vacuum agroinfiltration of aerial plant parts

Avocado, Persea americana Mill, is one of the most traded tropical fruits in the international market. To date, stable and transient transformation has only been achieved for of zygotic embryos and not of adult plant tissue, which limits functional genomics research. We provide the first transient Agrobacterium-mediated transformation methodology in avocado leaves that overcomes the recalcitrance to transformation of this species. We investigated the effect of Agrobacterium strain, leaf stage, wounding pre-treatment, the phytohormone jasmonic acid, and vacuum infiltration on transient transformation of avocado leaves. Using the Agrobacterium strain LBA4404 and the RUBY reporter a transformation frequency of up to 27% was obtained for avocado detached leaves. The transformation efficiency depended on the age of the leaf, with an intermediate stage of leaf development showing the highest efficiency of transient reporter gene expression. Microwounding pre-treatment facilitates agroinfiltration and coupled with leaf age are the primary factors influencing competence for transient transformation. Jasmonic acid did not significantly affect transient transformation in the absence of microwounding. However, microwounding and 250 µM of jasmonic acid acted synergistically to significantly enhance transient expression. Using this methodology with localized vacuum agroinfiltration, transient transformation of attached avocado leaves was achieved. This method unlocks the use of Agrobacterium-mediated transient transformation as a tool for explore gene function and metabolic pathways in both, detached and attached avocado leaves

A conjecture on Exceptional Orthogonal Polynomials

Exceptional orthogonal polynomial systems (X-OPS) arise as eigenfunctions of Sturm-Liouville problems and generalize in this sense the classical families of Hermite, Laguerre and Jacobi. They also generalize the family of CPRS orthogonal polynomials. We formulate the following conjecture: every exceptional orthogonal polynomial system is related to a classical system by a Darboux-Crum transformation. We give a proof of this conjecture for codimension 2 exceptional orthogonal polynomials (X2-OPs). As a by-product of this analysis, we prove a Bochner-type theorem classifying all possible X2-OPS. The classification includes all cases known to date plus some new examples of X2-Laguerre and X2-Jacobi polynomials

Phenomenological constraints on SUSY SU(5) GUTs with non-universal gaugino masses

We study phenomenological aspects of supersymmetric SU(5) grand unified theories with non-universal gaugino masses. For large tan beta, we investigate constraints from the requirement of successful electroweak symmetry breaking, the positivity of stau mass squared and the b to s gamma decay rate. In the allowed region, the nature of the lightest supersymmetric particle is determined. Examples of mass spectra are given. We also calculate loop corrections to the bottom mass due to superpartners.Comment: 10 pages, 2 figures (8 eps files), uses REVTeX. Replaced to match the version to be published in PRD: minor corrections and addition

Ocular related emergencies in Spain during the COVID-19 pandemic, a multicenter study

Purpose: To evaluate ophthalmological emergencies (OE) during the COVID-19 pandemic comparing them with the same period of the previous year. Methods: Retrospective observational study of all OE visits in four tertiary hospitals in Spain comparing data from March 16th to April 30th, 2020 (COVID-19 period) and the same period of 2019 (pre-COVID-19 period). Severity of the conditions was assessed following Channa et al. publication. Data on demographics, diagnosis and treatments were collected from Electronic Medical Records. Results: During lockdown, OE significantly declined by 75.18%, from 7, 730 registered in the pre-COVID-19 period to 1, 928 attended during the COVID-19 period (p < 0.001). In 2019, 23.86% of visits were classified as emergent, 59.50% as non-emergent, and 16.65% could not be determined. In 2020, the percentage of emergent visits increased up to 29.77%, non-emergent visits significantly decreased to 52.92% (p < 0.001), and 17.31% of the visits were classified as “could not determine”. During the pandemic, people aged between 45 and 65 years old represented the largest attending group (37.89%), compared to 2019, where patients over 65 years were the majority (39.80%). In 2019, most frequent diagnosis was unspecified acute conjunctivitis (11.59%), followed by vitreous degeneration (6.47%), and punctate keratitis (5.86%). During the COVID-19 period, vitreous degeneration was the first cause for consultation (9.28%), followed by unspecified acute conjunctivitis (5.63%) and punctate keratitis (5.85%). Conclusions: OE visits dropped significantly during the pandemic in Spain (75.18%), although more than half were classified as non-urgent conditions, indicating a lack of understanding of the really emergent ocular pathologies among population. © 2021, The Author(s)