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result(s) for
"Escobar, Sebastian"
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Consequences of a price incentive on free riding and electric energy consumption
by
Elinder, Mikael
,
Petré, Ingel
,
Escobar, Sebastian
in
Air pollution
,
Apartments
,
energy conservation
2017
This article shows that a simple monetary incentive can dramatically reduce electric energy consumption (EEC) in the residential sector and simultaneously achieve a more desirable allocation of EEC costs. The analyses are based on data from a policy experiment conducted in 2011 and 2012 by a private housing company in about 1,800 apartments. Roughly 800 of the tenants (treatment group) were subject to a change from having unlimited EEC included in their rent to having to pay the market price for their own EEC. This change was achieved by installing EEC meters in each apartment. Tenants in the other 1,000 apartments (control group) experienced no policy change and were subject to apartment-level billing and metering during the entire study period. Using a quasiexperimental research design and daily data on EEC from 2007 to 2015, we estimate that apartment-level billing and metering permanently reduce EEC by about 25%. Moreover, we show that households reduce EEC immediately after being informed that they will be billed for EEC, the reduction is larger when the production cost is higher, and the reduction in EEC comes almost exclusively from households with very high EEC before the policy change. Finally, we show that apartment-level billing and metering are cost-effective, with a cost per reduced kilowatt hour of US$0.01, and for each invested dollar, the social value of reductions in air pollution, including CO₂ emissions, is $2.
Journal Article
The Different Sources of Variation in Inbreeding Depression, Heterosis and Outbreeding Depression in a Metapopulation of Physa acuta
by
David, Patrice
,
Nicot, Antoine
,
Escobar, Juan Sebastian
in
Animals
,
Breeding
,
Genetic Markers
2008
Understanding how parental distance affects offspring fitness, i.e., the effects of inbreeding and outbreeding in natural populations, is a major goal in evolutionary biology. While inbreeding is often associated with fitness reduction (inbreeding depression), interpopulation outcrossing may have either positive (heterosis) or negative (outbreeding depression) effects. Within a metapopulation, all phenomena may occur with various intensities depending on the focal population (especially its effective size) and the trait studied. However, little is known about interpopulation variation at this scale. We here examine variation in inbreeding depression, heterosis, and outbreeding depression on life-history traits across a full-life cycle, within a metapopulation of the hermaphroditic snail Physa acuta. We show that all three phenomena can co-occur at this scale, although they are not always expressed on the same traits. A large variation in inbreeding depression, heterosis, and outbreeding depression is observed among local populations. We provide evidence that, as expected from theory, small and isolated populations enjoy higher heterosis upon outcrossing than do large, open populations. These results emphasize the need for an integrated theory accounting for the effects of both deleterious mutations and genetic incompatibilities within metapopulations and to take into account the variability of the focal population to understand the genetic consequences of inbreeding and outbreeding at this scale.
Journal Article
Kinetic gait analysis in English Bulldogs
by
de Souza, Alexandre Navarro Alves
,
Aristizabal Escobar, Andrés Sebastian
,
Matera, Julia Maria
in
Analysis
,
Animal Anatomy
,
Bone dysplasia
2017
Background
Canine breed conformation may interfere with locomotion and may predispose to orthopedic disease. Bulldogs have a high incidence of orthopedic diseases such as hip dysplasia. Kinetic gait analysis provides an objective way to assess and analyze locomotion. The aim of this study was to study the vertical forces of English Bulldogs during walk using a pressure sensitive walkway. We hypothesize that Bulldogs affected by orthopedic diseases have decreased weight bearing and asymmetric locomotion in the limbs despite having mild to no sings during clinical examination. Thirty English Bulldogs were tested. Peak vertical force, vertical impulse, rate of loading, stance phase duration, symmetry index, goniometry and incidence of orthopedic diseases were recorded.
Results
Although none of the dogs showed signs of pain or discomfort upon manipulation of the hip joints, all dogs had radiographic evidences of hip dysplasia and lack of significant peak vertical force, vertical impulse and stance time differences. The dogs had a mean hind limb symmetry index of 19.8 ± 19.5% and rates of loading ranged from 1.0 to 3.1.
Conclusions
Despite the lack of evident decrease in weight bearing, subclinical lameness can be inferred. The examined dogs had a mean hind limb symmetry index of 19.8 ± 19.5%. Symmetry indices reported in dogs free from orthopedic diseases range from 0.3 to 9.6%. Given non-lame dogs are expected to have a symmetry index close to 0%, data from this study suggests that Bulldogs have gait dysfunctions, which translates into hind limb asymmetries and rate of loading was consistent with severe hip dysplasia despite no visible signs of gait dysfunction. Future studies comparing lame and non-lame Bulldogs are warranted.
Journal Article
Ultrasound-Assisted Wound (UAW) Debridement in the Treatment of Diabetic Foot Ulcer: A Systematic Review and Meta-Analysis
by
López-Moral, Mateo
,
Lázaro-Martínez, José Luis
,
Flores-Escobar, Sebastián
in
Amputation
,
Bias
,
Cavitation
2022
A systematic review and meta-analysis were carried out to investigate the effect of ultrasound-assisted wound (UAW) debridement in patients with diabetic foot ulcers (DFUs). All selected studies were evaluated using the Cochrane risk of bias tool to assess the risk of bias for randomized controlled trials. PubMed and Web of Science were searched in October 2021 to find randomized clinical trials (RCT) assessing the effect of UAW debridement on DFUs. RevMan v5.4. was used to analyze the data with the Mantel–Haenszel method for dichotomous outcomes. A total of 8 RCT met our inclusion criteria, with 263 participants. Concerning the healing rate comparing UAW versus the control group, a meta-analysis estimated the pooled OR at 2.22 (95% CI 0.96–5.11, p = 0.06), favoring UAW debridement, with low heterogeneity (x2 = 7.47, df = 5, p = 0.19, I2 = 33%). Time to healing was similar in both groups: UAW group (14.25 ± 10.10 weeks) versus the control group (13.38 ± 1.99 weeks, p = 0.87). Wound area reduction was greater in the UAW debridement group (74.58% ± 19.21%) than in the control group (56.86% ± 25.09%), although no significant differences were observed between them (p = 0.24). UAW debridement showed higher healing rates, a greater percentage of wound area reduction, and similar healing times when compared with placebo (sham device) and standard of care in patients with DFUs, although no statistically significant differences were observed between groups.
Journal Article
NO CORRELATION BETWEEN INBREEDING DEPRESSION AND DELAYED SELFING IN THE FRESHWATER SNAIL PHYSA ACUTA
by
Sebastián Escobar, Juan
,
Sarda, Violette
,
Epinat, Guillaume
in
Animals
,
Biological Evolution
,
Correlation analysis
2007
Inbreeding depression, one of the main factors driving mating system evolution, can itself evolve as a function of the mating system (the genetic purging hypothesis). Classical models of coevolution between mating system and inbreeding depression predict negative associations between inbreeding depression and selfing rate, but more recent approaches suggest that negative correlations should usually be too weak or transient to be detected within populations. Empirical results remain unclear and restricted to plants. Here, we evaluate, for the first time, the within-population genetic correlation between inbreeding depression and a trait that controls the amount of self-fertilization (the waiting time) in a self-fertile hermaphroditic animal, the freshwater snail Physa acuta. Using a large quantitative-genetic design (36 grand-families and 348 families), we observe abundant within-population family-level genetic variation for both inbreeding depression (estimated for survival, fecundity, and size) and the degree of behavioral selfing avoidance. However, we detected no correlation between waiting time and inbreeding depression across families. In agreement with recent models, this result shows that mutational variance rather than differential purging accounts for most of the genetic variance in inbreeding depression within a population.
Journal Article
Strengthening protection against dangers coming from the sky
2024
The use of new methods and techniques of warfare in Colombia, such as bombing, especially of FARC dissident camps, has caused indiscriminate damage to the non-combatant civilian population, which is confronted with the protection given by International Humanitarian Law and its general principles that the armed forces must respect. However, in Colombia, “operational law” has attempted to justify these indiscriminate attacks, leaving the human rights protection in a secondary position. The creation of a Human Right to Protect the Freedom to Live Without Physical or Psychological Threat from Above may serve as a rule that prevents the use of air strikes and pursues their punishment if they do occur, rather than a criterion for determining when and when they are permissible.
Journal Article
Cacao (Theobroma cacao L.) climate zones and its associated agrobiodiversity in Arauca, Colombia
by
Vaillant, Fabrice
,
Pesca, Allende
,
Llano, Sandra
in
agrobiodiversity
,
Agroforestry
,
Biodiversity
2023
Cacao ( Theobroma cacao L) is one of the most relevant crops in terms of economy and social rural development in Colombia. Cacao is also an important crop due to its potential to replace illicit crops and it is related to less deforestation and preserves the biodiversity. There are several cacao districts in Colombia, one of these being Arauca. The Department of Arauca is the second largest cocoa producing region in Colombia; however, it is heavily affected by armed conflict. To raise the knowledge and technology available in the region, integrating data on the occurrence of cacao farms with climatic variables becomes a powerful socioeconomic mapping tool for maintaining agrobiodiversity and food security in the region. Consequently, this type of agrodiversity data and agroclimatic approaches help to better manage agrobiodiversity, as in the cacao region of Arauca. These tools are even more relevant in biodiverse regions, such as flooded savannahs and tropical forest ecosystems, which are currently undergoing drastic changes due to agricultural expansion and climate change. One of the knowledge gaps in Colombia´s cacao regions is that there are currently no agroclimatic maps made with a social and scientific approach. This study aimed to provide a database of the spatial distribution of cacao farms in Arauca, as well as agroclimatic maps that identify and locate cacao climate regions in Arauca. We also present a presence-only matrix consisting of twenty-six tree species, or agrobiodiversity, distributed across the study region and specifically associated with the cacao forestry systems in Arauca. We present the first database of both climate and agrobiodiversity data related to cacao farms in Arauca, developed with a research and socioeconomic vision that generated a novel approach for the agroclimatic zoning of cocoa in the Arauca Region and Colombia. Using 1,538 cacao farms at the regional scale, we identified two national and six regional-scale climate and soil regions. The selection at the local scale allowed us to classify 180 cacao farms comprising nine agroclimatic clusters in Arauca. We found twenty-six tree species distributed across the cacao climate zones. This dataset and its related maps also represent the agrobiodiversity of cultivated cacao locally. This is the most complete climate and agrobiodiversity dataset of cacao farms distribution in one of the top cocoa-producing regions in the country. These outputs are crucial because they constitute a baseline for developing research in the biodiversity of agroforestry systems, pests and diseases, pollutant presence, genetics, post-harvest processing and cocoa quality and safety.
Journal Article
Effect of CRISPR/Cas9 Targets Associated with Iron Metabolism and Its Variation on Transcriptional Regulation of SHK-1 Cell Line as a Model for Iron Metabolism
2024
In this study, we investigated the function of a gene associated with iron metabolism using CRISPR-Cas9 and RNA sequencing in SHK-1 salmon cells. Our objective was to understand how different guide RNA (gRNA) sequences against the transferrin gene tf could influence gene expression and cellular processes related to iron uptake. RNA-Seq analysis was performed to evaluate the transcriptomic effects of two distinct gRNA targets with high knock-out (KO) efficiencies for the targeted tf gene in the SHK-1 genome. Our results showed no significant differential expression in transferrin-related transcripts between wild-type and CRISPR-edited cells; however, there were major differences between their transcriptomes, indicating complex transcriptional regulation changes. Enrichment analysis highlighted specific processes and molecular functions, including those related to the nucleus, cytoplasm, and protein binding. Notably, different sgRNAs targeting tf might result in different mutations at DNA levels in SHK-1 salmon cells.
Journal Article
Expression of Kisspeptins and Kiss Receptors Suggests a Large Range of Functions for Kisspeptin Systems in the Brain of the European Sea Bass
2013
This study, conducted in the brain of a perciform fish, the European sea bass, aimed at raising antibodies against the precursor of the kisspeptins in order to map the kiss systems and to correlate the expression of kisspeptins, kiss1 and kiss2, with that of kisspeptin receptors (kiss-R1 and kiss-R2). Specific antibodies could be raised against the preprokiss2, but not the preoprokiss1. The data indicate that kiss2 neurons are mainly located in the hypothalamus and project widely to the subpallium and pallium, the preoptic region, the thalamus, the pretectal area, the optic tectum, the torus semicircularis, the mediobasal medial and caudal hypothalamus, and the neurohypophysis. These results were compared to the expression of kiss-R1 and kiss-R2 messengers, indicating a very good correlation between the wide distribution of Kiss2-positive fibers and that of kiss-R2 expressing cells. The expression of kiss-R1 messengers was more limited to the habenula, the ventral telencephalon and the proximal pars distalis of the pituitary. Attempts to characterize the phenotype of the numerous cells expressing kiss-R2 showed that neurons expressing tyrosine hydroxylase, neuropeptide Y and neuronal nitric oxide synthase are targets for kisspeptins, while GnRH1 neurons did not appear to express kiss-R1 or kiss-R2 messengers. In addition, a striking result was that all somatostatin-positive neurons expressed-kissR2. These data show that kisspeptins are likely to regulate a wide range of neuronal systems in the brain of teleosts.
Journal Article
Transferrin knockout reveals a tolerance phenotype against Piscirickettsia salmonis in Atlantic salmon phagocytes
by
Galdames-Contreras, Felipe
,
Jin, Yehwa
,
Pulgar, Rodrigo
in
Adaptive immunity
,
Analysis
,
Animals
2025
Salmonid rickettsial septicemia (SRS), caused by
Piscirickettsia salmonis
, is a major challenge in Chilean aquaculture. We evaluated the impact of the vaccine on fish survival, bacterial load, and iron metabolism-related gene expression under field conditions. Atlantic salmon received either a pentavalent inactivated vaccine plus a live attenuated
P. salmonis
vaccine (SIA) or a tetravalent control vaccine (SS). While survival was similar early (≤ 28 weeks post-seawater transfer), SIA-vaccinated fish showed greater survival by week 41 (85% vs. 52%). Quantitative PCR confirmed a reduced bacterial load in the SIA group during active infection. Expression analysis revealed distinct temporal regulation of iron metabolism genes: ferritin and hepcidin were upregulated in freshwater, whereas transferrin and its receptor were elevated in seawater in the SIA group, suggesting a link between iron homeostasis and vaccine-induced protection. To further investigate the role of transferrin, we generated transferrin-knockout (TF-KO) phagocytes using CRISPR/Cas9. In vitro infection assays revealed that, compared with wild-type (TF-WT) cells, TF-KO cells presented reduced cytopathic effects, decreased formation of
P. salmonis
-containing vacuoles (PCVs), and improved viability. Surprisingly, no differences in bacterial load or iron-related gene expression were detected between TF-KO and TF-WT cells, indicating that transferrin disruption did not directly alter iron homeostasis. Global transcriptomic analysis revealed 311 differentially expressed genes in TF-KO cells, with functional enrichment in metal-binding and zinc-dependent processes but no direct association with iron metabolism. These findings suggest that transferrin deficiency confers an infection-tolerant phenotype through transcriptional reprogramming unrelated to iron regulation, highlighting novel mechanisms of host‒pathogen interactions and potential avenues for SRS control in aquaculture.
Journal Article