175 research outputs found
Clasificación de los murciélagos de la región de los Tuxtlas, Veracruz, respecto a su respuesta a la fragmentación del hábitat
I propose three types of bat species according to their response to habitat fragmentation in Los Tuxtlas region: Type I (habitat dependent), Type II (vulnerable), and Type III (adaptable). Effects of habitat fragmentation on bat genetic structure will be primarily patent on Type I bats, and the major effect will be observed at long term.I propose three types of bat species according to their response to habitat fragmentation in Los Tuxtlas region: Type I (habitat dependent), Type II (vulnerable), and Type III (adaptable). Effects of habitat fragmentation on bat genetic structure will be primarily patent on Type I bats, and the major effect will be observed at long term
Los murciélagos y la COVID-19, una injusta historia
Las zoonosis, como la rabia, el paludismo o el dengue, han afectado a los humanos desde nuestro origen. Ante la COVID-19, nuestro objetivo es destacar que los murciélagos no son los culpables de la pandemia; por el contrario, son muchos los servicios que proporcionan al ser humano en la salud, la agricultura, la alimentación y la economía. No se ha encontrado el SARS-CoV-2 en ningún murciélago: el contagio de la COVID-19 es entre humanos; 70% de las enfermedades zoonóticas, como el SARS o el MERS, proviene de animales silvestres comercializados ilegalmente, por lo que es necesario eliminar la venta ilegal en mercados insalubres que representan un foco de contagios y proliferación de enfermedades infecciosas emergentes. El exterminio de murciélagos es perjudicial, no sólo para los propios murciélagos y el ecosistema, sino para nuestra salud, economía y bienestar
Los sistemas de transporte masivo en el hábitat metropolitano: El caso Megabús en el centro occidente colombiano
Este libro analiza e interpreta la manera en que se produjeron serios cambios en los atributos y relaciones en el hábitat metropolitano dentro del área conformada por los municipios de Pereira, Dosquebradas y La Virginia a raíz del diseño y puesta en servicio del Sistema de Transporte Masivo Megabús entre los años 2000 y 2010. Luego del planteamiento general del problema, los autores construyen un marco contextual de análisis que adopta tanto elementos propios de la visión sistémica desplegados por varios autores (Bunge, Quintanilla y Aibar, principalmente), como recientes aportes del constructivismo social, desarrollados todos ellos dentro de los estudios en Ciencia, Tecnología y Sociedad. El estudio particular de caso se desenvuelve a partir de un detallado trabajo documental que se acompaña del reconocimiento en campo de sus características más relevantes. Las conclusiones finales pretenden ampliar el margen de interpretación de los fenómenos socio técnicos y en particular de aquéllos que cuentan un importante número de actores involucrados en sus distintas fases de desarrolloAbstract: This text analyzes and interprets how serious changes were produced on the attributes and relationships within the metropolitan habitat in the area conformed by the municipalities of Pereira, Dosquebradas, and La Virginia stemming from the design and implementation of the Megabus Mass Transport System between 2000 and 2010. After the general statement of the problem, the authors construct a contextual analysis framework adopting elements from the systemic vision deployed by several authors (mainly Bunge, Quintanilla, and Aibar), as recent contributions of social constructivism; all developed within studies in Science, Technology, and Society. The specific case study develops from a detailed documentary work accompanied by field knowledge of its most relevant characteristics. The final conclusions seek to broaden the margin of interpretation of the socio-technical phenomena and particularly of those relayed by an important number of players involved in their distinct phases of developmen
Accumulation of scandium in plasma in patients with chronic renal failure
Scandium (Sc) is an element with many industrial applications, but relatively little is known about its physiological and/or toxicological effects, and very little data are available concerning the role of Sc in chronic renal failure (CRF). This paper examines the changes in plasma levels of Sc in predialysis patients with CRF and the relationship with blood parameters. The participants in this trial were 48 patients with CRF in predialysis and 53 healthy controls. Erythrocyte, haemoglobin, and haematocrit counts in blood were determined, and levels of creatinine, urea, uric acid, albumin, total protein and Sc were measured in plasma. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault index. The CRF patients were found to have higher plasma levels of creatinine, urea, uric acid, albumin, total protein, and Sc and a lower GFR than that the controls. Scandium in plasma was positively correlated with creatinine and plasma urea and negatively correlated with GFR, haemoglobin, and haematocrit and was associated with the risk of lower levels of erythrocytes, haemoglobin, and haematocrit. CRF was associated with increases in the circulating levels of scandium.This research was supported by Plan Nacional I+D Project 1FD 1997-0642
El Centro Interamericano de Vivienda - CINVA y los orígenes de la experimentación con bloques de tierra comprimida (BTC) en la vivienda social (1953-1957)
En este artículo se recoge la génesis de procesos constructivos con bloques de tierra comprimida (BTC) en países en desarrollo y como tema central se describe, valiéndose de fuentes primarias, el proceso experimental llevado a cabo en el Centro Interamericano de Vivienda - CINVA entre 1953 y 1957 que condujo tanto al desarrollo de la máquina Cinva-Ram para la producción de BTC, como al diseño y construcción de viviendas en este material, con el objeto de cualificar las técnicas de la edificación y lograr una vivienda de bajo costo para sectores rurales de América Latina. Las conclusiones están orientadas no solo a rescatar del olvido este ejercicio de naturaleza técnica y social, sino también a poner en evidencia la importancia del trabajo investigativo bajo principios de contextualización en el ámbito de la tecnología de la arquitectura
Effects of a Rehabilitation Programme Using a Nasal Inspiratory Restriction Device in COPD
Chronic obstructive pulmonary disease (COPD) patients are characterised for presenting dyspnea, which reduces their physical capacity and tolerance to physical exercise. The aim of this study was to analyse the effects of adding a Feel-Breathe (FB) device for inspiratory muscle training (IMT) to an 8-week pulmonary rehabilitation programme. Twenty patients were randomised into three groups: breathing with FB (FBG), oronasal breathing without FB (ONBG) and control group (CG). FBG and ONBG carried out the same training programme with resistance, strength and respiratory exercises for 8 weeks. CG did not perform any pulmonary rehabilitation programme. Regarding intra group differences in the value obtained in the post-training test at the time when the maximum value in the pre-training test was obtained (Post(PRE)), FBG obtained lower values in oxygen consumption (VO2, mean = -435.6 mL/min, Bayes Factor (BF10) > 100), minute ventilation (VE, -8.5 L/min, BF10 = 25), respiratory rate (RR, -3.3 breaths/min, BF10 = 2), heart rate (HR, -13.7 beats/min, BF10 > 100) and carbon dioxide production (VCO2, -183.0 L/min, BF10 = 50), and a greater value in expiratory time (Tex, 0.22 s, BF10 = 12.5). At the maximum value recorded in the post-training test (Post(FINAL)), FBG showed higher values in the total time of the test (T-t, 4.3 min, BF10 = 50) and respiratory exchange rate (RER, 0.05, BF10 = 1.3). Regarding inter group differences at Pre(POST), FBG obtained a greater negative increment than ONBG in the ventilatory equivalent of CO2 (EqCO(2), -3.8 L/min, BF10 = 1.1) and compared to CG in VE (-8.3 L/min, BF10 = 3.6), VCO2 (-215.9 L/min, BF10 = 3.0), EqCO2 (-3.7 L/min, BF10 = 1.1) and HR (-12.9 beats/min, BF10 = 3.4). FBG also showed a greater Pre(POST) positive increment in Tex (0.21 s, BF10 = 1.4) with respect to CG. At Pre(FINAL), FBG presented a greater positive increment compared to CG in T-t (4.4 min, BF10 = 3.2) and negative in VE/VCO2 intercept (-4.7, BF10 = 1.1). The use of FB added to a pulmonary rehabilitation programme in COPD patients could improve tolerance in the incremental exercise test and energy efficiency. However, there is only a statically significant difference between FBG and ONBG in EqCO(2). Therefore, more studies are necessary to reach a definitive conclusion about including FB in a pulmonary rehabilitation programme
Deforestation impacts on bat functional diversity in tropical landscapes
"Functional diversity is the variability in the functional roles carried out by species within ecosystems. Changes in the environment can affect this component of biodiversity and can, in turn, affect different processes, including some ecosystem services. This study aimed to determine the effect of forest loss on species richness, abundance and functional diversity of Neotropical bats. To this end, we identified six landscapes with increasing loss of forest cover in the Huasteca region of the state of Hidalgo, Mexico. We captured bats in each landscape using mist nets, and calculated functional diversity indices (functional richness and functional evenness) along with species richness and abundance. We analyzed these measures in terms of percent forest cover. We captured 906 bats (Phyllostomidae and Mormoopidae), including 10 genera and 12 species. Species richness, abundance and functional richness per night are positively related with forest cover. Generalized linear models show that species richness, abundance and functional richness per night are significantly related with forest cover, while seasonality had an effect on abundance and functional richness. Neither forest cover nor season had a significant effect on functional evenness. All these findings were consistent across three spatial scales (1, 3 and 5 km radius around sampling sites). The decrease in species, abundance and functional richness of bats with forest loss may have implications for the ecological processes they carry out such as seed dispersal, pollination and insect predation, among others.
Isolation and characterization of a Bacillus velezensis D‑18 strain, as a potential probiotic in European seabass aquaculture
Author's accepted version (postprint)This is an Accepted Manuscript of an article published by Springer in Probiotics and Antimicrobial Proteins on 03/04/2021Available online: https://link.springer.com/content/pdf/10.1007/s12602-021-09782-8.pdfWithin the food-producing sectors, aquaculture is the one that has developed the greatest growth in recent decades, currently representing almost 50% of the world’s edible fish. The diseases can affect the final production in intensive aquaculture; in seabass, aquaculture vibriosis is one of the most important diseases producing huge economical losses in this industry. The usual methodology to solve the problems associated with the bacterial pathology has been the use of antibiotics, with known environmental consequences. This is why probiotic bacteria are proposed as an alternative fight against pathogenic bacteria. The aim of this study was to analyse a strain of Bacillus velezensis D-18 isolated from a wastewater sample collected from a fish farm, for use as probiotics in aquaculture. The strain was evaluated in vitro through various mechanisms of selection, obtaining as results for growth inhibition by co-culture a reduction of 30%; B. velezensis D-18 was able to survive at 1.5-h exposure to 10% seabass bile, and at pH 4, its survival is 5% and reducing by 60% the adhesion capacity of V. anguillarum 507 to the mucus of seabass and in vivo by performing a challenge. Therefore, in conclusion, we consider B. velezensis D-18 isolate from wastewater samples collected from the farms as a good candidate probiotic in the prevention of the infection by Vibrio anguillarum 507 in European seabass after in vitro and biosafety assays.acceptedVersio
Accumulation of Scandium in Plasma in Patients with Chronic Renal Failure
Scandium (Sc) is an element with many industrial applications, but relatively little is known about its physiological and/or toxicological effects, and very little data are available concerning the role of Sc in chronic renal failure (CRF). This paper examines the changes in plasma levels of Sc in predialysis patients with CRF and the relationship with blood parameters. The participants in this trial were 48 patients with CRF in predialysis and 53 healthy controls. Erythrocyte, haemoglobin, and haematocrit counts in blood were determined, and levels of creatinine, urea, uric acid, albumin, total protein and Sc were measured in plasma. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault index. The CRF patients were found to have higher plasma levels of creatinine, urea, uric acid, albumin, total protein, and Sc and a lower GFR than that the controls. Scandium in plasma was positively correlated with creatinine and plasma urea and negatively correlated with GFR, haemoglobin, and haematocrit and was associated with the risk of lower levels of erythrocytes, haemoglobin, and haematocrit. CRF was associated with increases in the circulating levels of scandium
Theoretical modelling of quaternary GaInAsSb/GaAs self-assembled quantum dots
Trabajo presentado al "Quantum Dot", celebrado en Nottingham (UK) del 26 al 30 de Abril de 2010.InAs/GaAs quantum dots exposed to Sb after growth exhibit spectral changes. We study
in the present paper an idealized nanostructure consisting of a homogeneous distribution of the
quaternary GaInAsSb surrounded by a barrier of GaAs. We nd that the valence band o set is
a critical parameter in modelling its electronic structure. Depending on this value, we predict a
transition from type-I to type-II band alignment at a di erent Sb concentration. The addition
of Sb to reduce the transition energy while keeping a type-I alignment is only of bene t at low
Sb concentrationThis work was supported by the Spanish MICINN (projects TEC2008-06756-C03-01/02/TEC,
CONSOLIDER INGENIO 2010 CSD2006-0019 and CSD2009-00013), the Junta de Andalucía
(PAI research groups TEP-120 and TIC-145; project P08-TEP-03516) and Comunidad Autónoma de Madrid S2009ESP-1503.Peer reviewe
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