47 research outputs found
Selection for ovulation rate in rabbits
El objetivo de esta tesis ha sido estudiar la respuesta directa a la selección por tasa de ovulación en conejo y las respuestas correlacionadas en tamaño de camada y tasas de supervivencia.
Los animales pertenecían a una línea de conejos seleccionada por tasa de ovulación durante 10 generaciones. La selección se realizó en base al valor fenotípico de la hembra, que se midió el día 12 de la segunda gestación mediante laparoscopia. Se creó una línea control a partir de la recuperación de aproximadamente 470 embriones de 50 hembras donantes de la generación base. Los embriones fueron vitrificados y almacenados en nitrógeno líquido hasta su transferencia al final del experimento de selección (generación 10 de la línea seleccionada).
Se midieron los siguientes caracteres: tamaño de camada (LS), estimada como el número total de gazapos al parto en un máximo de 5 partos; tasa de ovulación (OR), estimada como el número de cuerpos lúteos en los dos ovarios; tasa de ovulación derecha y tasa de ovulación izquierda (ROR y LOR); el número de embriones implantados totales (IE), en el lado derecho (RIE) y en el lado izquierdo (LIE); la diferencia ovulatoria (OD), definida como la diferencia entre ROR y LOR, expresada en valor absoluto; la diferencia de implantación (ID), definida como la diferencia entre RIE y LIE, expresada en valor absoluto; la supervivencia embrionaria (ES), calculada como IE/OR; la supervivencia fetal (FS), calculada como LS/IE; la supervivencia prenatal (PS), calculada como LS/OR.
Se utilizó metodología bayesiana para analizar los datos. Las estimas de las heredabilidades de OR, LS, ES, FS y PS fueron 0.16, 0.09, 0.09, 0.24 y 0.14, respectivamente. Las estimas de las correlaciones fenotípicas de OR con LS, ES, FS y PS fueron 0.09, -0.07, -0.26 and -0.28, respectivamente. Las estimas de las correlaciones genéticas de OR con LS y ES tuvieron una baja precisión, y no se pudo concretar su signo. Las estimas de las correlaciones genéticas de OR con FS y PS fueron negativas (probabilidad de ser negativa de 1.00 y 0.98, respectivamente). Las correlaciones fenotípicas y genéticas entre LS y las tasas de supervivencias fueron positivas (probabilidad de ser positivas de 1.00).Laborda Vidal, P. (2011). Selection for ovulation rate in rabbits [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14121Palanci
Depopulation in Spain and violation of occupational rights
This article aims at revealing the impacts of depopulation in terms of the violation of the occupational rights of people who live in rural areas, away from large urban centres. The starting point is an overview of the inequalities that emerge in neglected rural areas in the European Union, followed by an analysis of the Spanish context with ageing as a salient factor. Then, the influence of rural territories on occupation is assessed, discussing the violation of occupational rights. Finally, there is a description of different macro and micro actions to address some of the occupational injustices in rural areas and to favour equality in the exercise of occupational rights from the standpoint of occupational science
Detection, quantification, and characterization of polystyrene microplastics and adsorbed bisphenol A contaminant using electroanalytical techniques
The potential applications of electroanalytical techniques for the quantification and size characterization of nonelectroactive polystyrene microplastics is reported, in addition to characterizing the kinetics of adsorption of bisphenol A on these polystyrene microparticles. The individual adsorption events of very diluted polystyrene microparticles dispersions on glassy-carbon microelectrodes produce the blocking of the charge transfer of a mediator (ferrocene-methanol) thus decreasing the current of the recorded chronoamperogram in a stepwise manner. The magnitude of the current steps are in the order of pA values and can be related to the diameter of the plastic microparticles in the size range 0.1 to 10 µm. The frequency of the current steps in the domain time used (120 s) allows to quantify the number concentration of these microparticles in the range 0.005 to 0.500 pM. Electrochemical impedance spectroscopy confirms the adsorption of the polystyrene microplastics on carbon microelectrodes (and to a lesser extent on platinum microelectrodes) under the same experimental conditions as above. On the other hand, the adsorbed microplastics become concentrators of other pollutants found in the environment. The sensitive differential-pulse voltammetry determination of bisphenol A (linear range 0.80–15.00 µM; detection limit 0.24 µM) was used together with a simple separation procedure for studying the adsorption of bisphenol A on polystyrene microparticles. The adsorption capacity (mg of bisphenol A retained per g of the polystyrene microplastics) decreased from approximately 5.7 to 0.8 mg g−1 with increasing dosages of polystyrene microparticles from 0.2 to 1.6 g l−1. The adsorption isotherms were modeled resulting in a monolayer of bisphenol A adsorbed on the microplastics (i.e., best fitted to a Langmuir model)
Desigualdad y redistribución en la Unión Europea
El objetivo de este Trabajo es mostrar un análisis detallado sobre la eficacia de diversos factores de redistribución, como puedan ser los impuestos, el Producto Interior Bruto per cápita y las transferencias. Se parte para ello de una visión estructural de las variables macroeconómicas para la Unión Europea y de su posición actual en dichos parámetros, así como de un análisis de la literatura al respecto, que existe para la OCDE. Posteriormente, se aplican los datos vistos, así como otros extraídos para este propósito, en el análisis econométrico de las relaciones de las variables descritas con el índice de Gini en sí. Como resultado, podemos ver que hay indicadores, como los anteriormente especificados, que sí influyen en el índice de Gini para el conjunto de los 28 países de la Unión Europea, y aunque otros indicadores auxiliares no son tan influyentes en la desigualdad también nos permiten ver efectos complementarios. El análisis no es tan preciso como el planteado para la OCDE; no obstante, tiene suficientes elementos para posteriores investigaciones a este respecto
Detection, size characterization and quantification of silver nanoparticles in consumer products by particle collision coulometry
Silver nanoparticles (AgNPs) are widely used in industrial and consumer products owing to its antimicrobial nature and multiple applications. Consequently, their release into the environment is becoming a big concern because of their negative impacts on living organisms. In this work, AgNPs were detected at a potential of + 0.70 V vs. Ag/AgCl reference electrode, characterized, and quantified in consumer products by particle collision coulometry (PCC). The electrochemical results were compared with those measured with electron microscopy and single-particle inductively coupled plasma mass spectrometry. The theoretical and practical peculiarities of the application of PCC technique in the characterization of AgNPs were studied. Reproducible size distributions of the AgNPs were measured in a range 10–100 nm diameters. A power allometric function model was found between the frequency of the AgNPs collisions onto the electrode surface and the number concentration of nanoparticles up to a silver concentration of 1010 L-1 (ca. 25 ng L-1 for 10 nm AgNPs). A linear relationship between the number of collisions and the number concentration of silver nanoparticles was observed up to 5 × 107 L-1. The PCC method was applied to the quantification and size determination of the AgNPs in three-silver containing consumer products (a natural antibiotic and two food supplements). The mean of the size distributions (of the order 10–20 nm diameters) agrees with those measured by electron microscopy. Graphical abstract: [Figure not available: see fulltext.]
Wavelength Dispersive X-ray Fluorescence Method Development for Asphaltene Samples
This study was carried out at Neste Research and Development unit in Porvoo. The aim was to develop a specialised quantitative method for asphaltene samples with wavelength dispersive X-ray fluorescence (WDXRF). Prior to this work the samples were analysed with a semi-quantitative WDXRF method and improvements in accuracy were wanted especially for the lower concentration range (0-100 ppm).
Over twenty elements are measured from the asphaltene samples with WDXRF but for this work twelve elements were included: potassium, calcium, chromium, manganese, cobalt, copper, zinc, cadmium, tin, antimony, thallium and lead.
XRF is a non-destructive analytical method, where the matrix has a strong influence to the received results. Samples are measured as undiluted with minimal sample preparation and high sensitivity is gained. WDXRF allows to optimise the measuring parameters for each analyte individually and high resolution can be obtained.
In this work reliable and reproducible calibration sample preparation was accomplished with pipetting various concentrations of element standards into ethanol and mixing a representative blank sample into it. The calibration samples were air-dried in a fume hood and pressed as pellets afterwards. Linear spiking concentrations were obtained.
For each measured element the measuring conditions were optimized: Different X-ray tube settings, primary filters, analysing crystals and collimators were tested with quick (~3 min) qualitative analyses. Background positions and pulse height analyser windows were set in the quantitative method. The calibration curves were measured and corrections were applied if needed, and high accuracy curves were achieved (RSD <0.0001-0.0006%). Longevity of the method was ensured with suitable drift samples.
The method development produced a quantitative WDXRF method for asphaltene samples which can now be further tested and validated. The study also gained the laboratory knowledge for expanding the rest of the analysed elements under a quantitative WDXRF method as well.Opinnäytetyö suoritettiin Nesteen Tutkimus- ja kehitysyksikössä Porvoon jalostamolla. Työn tarkoituksena oli kehittää kvantitatiivinen menetelmä asfalteeninäytteille aallonpituusdispersiivisellä röntgenfluoresenssispektrometrialla (WDXRF). Työn tavoitteena oli kehittää näytematriisille tarkka menetelmä, joka keskittyisi mataliin pitoisuuksiin (0-100 ppm). Ennen tätä työtä asfalteeninäytteet oli mitattu puolikvantitatiivisella menetelmällä.
Asfalteeneista mitataan WDXRF:lla yli 20 alkuainetta, mutta tämän työn menetelmään sisällytettiin 12 alkuainetta kohtuullisen työmäärän saavuttamiseksi: kalium, kalsium, kromi, mangaani, koboltti, kupari, sinkki, kadmium, tina, antimoni, tallium ja lyijy.
Röntgenfluoresenssispektrometriassa näytettä ei hajoteta ja näytematriisilla on suuri vaikutus saatuihin tuloksiin, mutta korkea sensitiivisyys saavutetaan. Näytteet voidaan mitata laimentamattomina ja näytteiden esikäsittely on yksinkertaista ja nopeaa. WDXRF:n optiikka mahdollistaa korkean resoluution sekä jokaisen mitattavan alkuaineen erillisen optimoinnin.
Menetelmän kehitys aloitettiin oikeellisten ja toistettavien kalibrointinäytteiden valmistamisesta. Toimiva lineaarinen standardin lisäysmenetelmä saavutettiin pipetoimalla alkuaine-standardeja eri pitoisuuksissa etanoliin, johon nolla-näyte sekoitettiin. Kalibrointinäytteiden annettiin kuivua vetokaapissa ja näytteet painettiin puristenapeiksi analysointia varten.
Jokaiselle kalibroitavalle alkuaineelle optimoitiin mittausparametrit kokeilemalla eri röntgenputkiasetuksia, suodattimia, analyysikristalleja ja kollimaattoreja lyhyillä (~3 min) kvalitatiivisilla mittauksilla. Kvantitatiivisessa menetelmässä mittauspisteille määritettiin taustapisteet sekä sopiva pulssi-ikkuna. Mitatut kalibrointisuorat noudattivat korkeaa tarkkuutta (RSD <0,0001-0,0006 %). Kalibroinnin jälkeen kalibrointisuorille mitattiin referenssi-intensiteetit drift-näytteillä menetelmän ylläpidon mahdollistamiseksi.
Työn tuloksena onnistuttiin kehittämään kvantitatiivinen WDXRF-menetelmä asfalteeninäytteille validointia ja käyttöönottoa varten. Menetelmän kehitys antoi laboratoriolle mallin siirtää loputkin WDXRF:lla analysoitavat alkuaineet uudelle kvantitatiiviselle menetelmälle
Comparison of the spread of two different volumes of contrast medium when performing ultrasound-guided transversus abdominis plane injection in dog cadavers
ObjectivesTo compare, via CT imaging, the spread of different volumes of diluted iodinated contrast medium in the transversus abdominis muscle plane of dog cadavers.MethodsProspective, randomised study. An electro stimulation or a SonoTAP needle was inserted in plane with the ultrasound beam in the fascia between the internal oblique and transversus abdominis muscles. A test dose of 1 ml of diluted contrast (30 mg/mL iohexol) was injected to confirm positioning, followed by 0 · 5 mL/kg (n=14) or 1 mL/kg (n=12) and the distribution of the fluid compared.ResultsContrast medium was identified exclusively in the transversus abdominis plane in 19 of 26 dogs. In one dog, the contrast lay between the external and internal oblique muscles and partially in three dogs. Intraperitoneal contrast was detected in 6 of 26 dogs (23%). No significant differences were found in the dorso-ventral or cranio-caudal spread or area of distribution but a significant difference was found in the transverse spread. There was an association between poor ultrasound visualisation of the tip of the needle and intraperitoneal injection.Clinical significanceInjection of 1 mL/kg of diluted contrast did not result in wider cranio-caudal spread in the transversus abdominis muscle plane of dog cadavers when compared with 0 · 5 mL/kg. Intraperitoneal injection is a risk and might be reduced with good needle visualisation
Comparison between echocardiographic and non-ECG-gated CT measurements in dogs
The aim of this study was to compare echocardiographic measurements with non-ECG-gated contrast-enhanced cardiac CT measurements in dogs. Fifty-seven dogs were included in the study. The following echocardiographic parameters were measured: M-mode interventricular septum in diastole and systole, left ventricular internal diameter in diastole and systole, left ventricular free wall in diastole and systole, 2D left atrial maximal diameter, 2D left atrium to aorta ratio in diastole, 2D aortic annulus in systole and 2D pulmonary annulus in diastole and systole. CT measurements were obtained from multiplanar reconstruction images, replicating the imaging planes used for 2D measurements on echocardiography. It was not possible to discriminate between systole and diastole. The results showed moderate Lin's concordance correlation coefficients between the left ventricular internal diameter in systole (0.77), the aortic annuli (0.84) and the pulmonary annuli in diastole (0.78) and systole (0.80). Low coefficients were obtained between the other parameters. Bland-Altman plots for the parameters with highest concordance correlation coefficients were calculated. They suggested equivalence between the measurements of the aortic annuli. Equivalence was not seen between the remaining echocardiographic and CT measurements. Therefore, non-ECG-gated CT is not a reliable way of quantitatively assessing cardiac size
Analytical applications of single particle inductively coupled plasma mass spectrometry: a comprehensive and critical review
Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) refers to the use of ICP-MS as a particle counting technique. When ICP-MS measurements are performed at very high data acquisition frequencies, information about (nano)particles containing specific elements and their dissolved forms can be obtained (element mass per particle, size and number and mass concentrations). As a result of its outstanding performance, SP-ICP-MS has become a relevant technique for the analysis of complex samples containing inorganic nanoparticles. This review discusses the maturity level achieved by the technique through the methods developed for the detection, characterisation and quantification of engineered and natural (nano)particles. The application of these methods in different analytical scenarios is comprehensively reviewed and critically discussed, with special attention to their current technical and metrological limitations. The emergent applications of SP-ICP-MS in the field of nanoparticle-tagged immunoassay and hybridization methods are also reviewed
Incidence, hospitalization, mortality and risk factors of COVID-19 in long-term care residential homes for patients with chronic mental illness
Long-term care residential homes (LTCRH) for patients with chronic mental illness have suffered the enormous impact of COVID-19. This study aimed to estimate incidence, hospitalization, mortality, and risk factors of COVID-19 to prevent future epidemics. From March 2020 to January 2021 and before vaccination anti-SARS-CoV-2 begins, cumulate incidence rate (CIR), hospitalization rate (HR), mortality rate (MR), and risk factors of COVID-19 in the 11 LTCRH of two Health Departments of Castellon (Spain) were studied by epidemiological surveillance and an ecological design. Laboratory tests confirmed COVID-19 cases, and multilevel Poisson regression models were employed. All LTCRH participated and comprised 346 residents and 482 staff. Residents had a mean age of 47 years, 40% women, and suffered 75 cases of COVID-19 (CIR = 21.7%), five hospitalizations (HR = 1.4%), and two deaths (MR = 0.6%) with 2.5% fatality-case. Staff suffered 74 cases of the disease (CIR = 15.4%), one hospitalization (HR = 0.2%), and no deaths were reported. Risk factors associated with COVID-19 incidence in residents were private ownership, severe disability, residents be younger, CIR in municipalities where LTCRH was located, CIR in staff, and older age of the facilities. Conclusion: COVID-19 incidence could be prevented by improving infection control in residents and staff and modernizing facilities with increased public ownership