1,288 research outputs found
An Analysis of the Impact of Various Sampling Designs on the Headcount Index: A Simulation Study Based on the EU-SILC
The analysis and the comparison of poverty between regions and countries are important topics in social sciences, which have relevant demands of many national (Cáritas, Intermón Oxfam, Cruz Roja, etc) and international (UN, World Bank, OECD, Eurostat, IMF, etc) agencies and organizations. One of the most common poverty indicators in practice is the headcount index, which analyzes the proportion of individuals considered as poor in a population. In this paper, we first analyze the impact on the headcount index when different sampling designs are considered. Note that this study is based on real data sets taken from different countries of the European Union, and the empirical measures for comparisons are based on different Monte Carlo simulation studies. For instance, we observe that stratified sampling has the best performance in comparison to alternative sampling designs. Post-stratification performs similar to simple random sampling without replacement, and the use of auxiliary information provides similar results to ones derived from stratified sampling. Second, we also analyze the empirical performance of different variance estimators under the commented sampling designs. We conclude that they have a similar empirical performance, and they provide, in general, confidence intervals with desirable coverage rates
Contribución a la corología de las macroalgas marinas bentónicas del litoral malagueño. I.
Continuando con un proyecto sobre la corología de las macroalgas marinas bentónicas del litoral malagueño (Conde, 1981; Conde, 1984; Conde & Soto, 1986) reseñamos en esta nota la presencia en la zona de 5 nuevas especies, y se confirman otras 5, citadas anteriormente en la literatura o de arribazón. La ordenación de las especies se ha realizado según la propuesta de Gallardo ét al. (1985)
Aspectos ultraestructurales de algunas coralináceas (Rhodophyta) del Mediterráneo andaluz (S. de España).
En el presente artículo se estudian e interpretan al microscopio electrónico de barrido (M.E.B.) algunos caracteres cualitativos de siete especies de algas coralináceas del litoral andaluz, pertenecientes a los géneros Corallina,Jania y Amphiroa.Using the scanning electron microscopy some qualitatives characteristics of seven seaweeds species of the mediterranean coasts of Andalucía (S. of Spain), of the genus Corallina, Junio y Amphiroa have been studied
The burn severity and plant recovery relationship affect the biological and chemical soil properties of Pinus halepensis Mill. stands in the short and midterms after wildfire
In the Mediterranean Basin, changes in climate and fire regime (increased recurrence and severity) reduce
ecosystem services after wildfires by increasing soil degradation and losses in plant diversity. Our study was a
biological approach to relate soil properties to vegetation recovery and burn severity. We focused our study on
the natural recovery of the soil-plant interphase in Pinus halepensis Mill. forests located in the SE of Iberian
Peninsula, a semiarid climate. We included some chemical properties 3 years after fire (available phosphorus (P)
and soil organic carbon (Corg), among others), and biological soil indicators 3 and 5 years after fire (i.e. basal
soil respiration (BSR), microbial biomass carbon (Cmic), carbon mineralization coefficient (Cmineral), metabolic
quotient (qCO2) and microbial quotient (Cmic:Corg)). We analyzed the activity of three different enzymes: urease
(UR), phosphatase (PHP) and β-glucosidase (GLU).
The changes in most chemical properties were ephemeral, but P and Corg showed higher values in burned
areas, and the highest were found for low-moderate severity. Plant recovery was the triggering factor for the
recovery of Corg and biological soil function. Burn severity and time after fire influenced Cmic and the
Cmic:Corg, which were higher for moderate-high severity 3 years later, but were below the unburned values 5
years after fire. The microbial activities of GLU and UR were recovered in burned areas 5 years after fire. The
PHP values lowered according to higher burn severity and time after fire. The soil ecological trends obtained by a
principal component analysis revealed a relationship linking GLU, BSR and qCO2 that explained soil response to
burn severity. PHP, Cmic and Cmic:Corg explained most of the variability related to time after fire.
Our results provide insights into how burn severity, in Mediterranean fire-prone Aleppo pine stands,
modulated the natural plant recovery linked to soil biochemical and microbiological response to fire. High burn
severity limited natural vegetation recovery, and both reduced biological soil functionality. This knowledge can
be implemented in post-fire planning to apply post-fire management (for mitigation and restoration) in which
the “no intervention” tool should be contemplated. These findings provide information to be applied in adaptive
forest management to improve the resilience of vulnerable ecosystems and to reduce burn severity in future fire
events.This study was supported by a research award provided by the Instituto Estudios Albacetenses (IEA2016-Daniel Moya) and funds provided to the Forest Ecology Research Group by the University Castilla-La Mancha.The authors also thank the Spanish Institute for Agricultural and Food Research and Technology (INIA) for the funding awarded through National Research Projects GEPRIF (RTA2014-00011-C06), POSTFIRE_CARE (CGL2016-75178-C2-1-R) financed by the Spanish Research Agency (AIE), and the European Union for European Funding for Regional Development (FEDER)
Developing strategies to reduce spray drift in pneumatic spraying in vineyards: Assessment of the parameters affecting droplet size in pneumatic spraying
Pneumatic sprayers are widely used in vineyards due to their very fine droplet size, which makes the drift risk to become an important problem to be considered. The aim of this study was to assess the effect of the spout diameter at the release point on the spray droplet size and uniformity achieved for different liquid flow rates (LFR) and air flow rates (AFR).A test bench was developed to simulate a real pneumatic sprayer under laboratory conditions, and it was empirically adjusted to match the air pressure conditions as closely as possible to real working conditions. Two positions of insertion of the liquid hose, the conventional position (CP) and an alternative position (AP), were tested for three LFRs, 1.00, 1.64, and 2.67Lmin-1, and four AFRs, 0.280, 0.312, 0.345, and 0.376m3 s-1. The air speed decrease between the two insertion points of the liquid hose was measured. A Malvern SprayTec® instrument was used to measure the droplet size, and the D50, D10, and D90 parameter values were obtained. The relative SPAN factor (RSF) was also calculated. A model to predict variations in D50 was fitted using the aforementioned parameters.The results show that variations in the diameter of the spout significantly change the droplet size, producing a mean increase of 59.45% in D50 and similar increases in D10 and D90. The model developed to predict variations in D50 has a very high degree of accuracy (R2 =0.945). The relative decrease in the air speed along the spout did not present significant differences for the different airflow rates tested. The results of the study show that the droplet size produced in pneumatic spraying can be modified easily by varying the air spout dimensions. This should be taken into account by manufacturers from a design point of view.Postprint (author's final draft
GAM9: Gamificación de Asignaturas del Módulo 9 "Conocimientos y técnicas aplicadas a la comunicación publicitaria”
La gamificación consiste en la aplicación de conceptos que encontramos habitualmente en los juegos en general y en los videojuegos en concreto. Estos elementos son: reglas, retos progresivos con un camino definido para alcanzarlos, feedback continuo sobre la progresión, y compromiso por parte del jugador. Aunque el concepto es una herramienta muy utilizada en marketing, también se empieza a trasladar lo positivo de las mecánicas del juego a la docencia. Dado que gran parte del alumnado dedica su tiempo libre a los videojuegos, es de esperar que esta dinámica sea incluso más positiva que en otros campos. Gamificar una asignatura puede motivar al estudiante, guiarlo en el proceso de aprendizaje y fomentar una sana competitividad. Por esta razón, nos proponemos concretar para el curso 2014/15 propuestas de gamificación en tres asignaturas del grado en Publicidad y Relaciones Públicas, pertenecientes al módulo “Conocimientos y Técnicas aplicadas a la comunicación publicitaria” con el objetivo de motivar el aprendizaje de nuestro alumnado
Reducing spray drift by adapting the spraying equipment to the canopy shape in olive orchards with isolated trees
The lack of specificity of the spraying equipment commonly used in olive orchards is a
remarkable problem, for not allowing farmers to apply adjusted pesticide doses to their trees, making necessary to spray very high liquid volumes that increase the environmental pollution risk. In this context, three prototypes were specially developed to increase the application efficiency in olive orchards with isolated trees, which represent 98% of the olive harvested area in Spain.Postprint (published version
Better Fitness in Captive Cuvier’s Gazelle despite Inbreeding Increase: Evidence of Purging?
Captive breeding of endangered species often aims at preserving genetic diversity and to
avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding
depression can be purged when inbreeding persists over several generations. Despite its
great importance both for evolutionary biology and for captive breeding programmes, few
studies have addressed whether and to which extent purging may occur. Here we undertake
a longitudinal study with the largest captive population of Cuvier's gazelle managed
under a European Endangered Species Programme since 1975. Previous results in this
population have shown that highly inbred mothers tend to produce more daughters, and this
fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by
changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as
surplus individuals in the population). Here, by using studbook data we explore whether
purging has occurred in the population by investigating whether after the change in pairing
strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival)
increased, and c) the relationship between inbreeding and juvenile survival, was positive.
Consistent with the existence of purging, we found an increase in inbreeding
coefficients, homozygosity and juvenile survival. In addition, we showed that in the course
of the breeding programme the relationship between inbreeding and juvenile survival was
not uniform but rather changed over time: it was negative in the early years, flat in the middle
years and positive after the change in pairing strategy.We highlight that by allowing inbred
individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable
managing strategy to reduce the surplus of males that force most zoos to use ethical
culling and euthanizing management tools. We discuss these possibilities but also acknowledge
that many other effects should be considered before implementing inbreeding and
purging as elements in management decisions
Composition of free and adherent ruminal bacteria: inaccuracyof the microbial nutrient supply estimates obtained using freebacteria as reference samples and 15N as the marker
Previous studies have indicated that 15N enrichment of solid-associated bacteria (SAB) may be predicted from the same value in liquid-associated bacteria (LAB). The aims of this study were to confirm this and to measure the error in the nutrient supply from SAB, when LAB are used as the reference sample. For this purpose, the chemical and amino acid (AA) compositions of both the bacterial populations were studied in four experiments carried out on different groups of three rumen cannulated wethers. Diets (one in Experiments 1 and 4 and three in Experiments 2 and 3) had forage-to-concentrate ratios (dry matter (DM) basis) between 2 : 1 and 40 : 60, and were consumed at intake levels between 40 and 75 g DM/kg (BW) 0.75. The bacteria samples were isolated after continuous infusion of ( 15NH 4) 2SO 4 (40, 18, 30 and 25 mg 15N/day, in Experiments 1 to 4, respectively) for at least 14 days. In all experiments, SAB had consistently higher concentrations of organic matter (826 v. 716 g/kg DM, as average) and total lipids (192 v. 95 g/kg DM, as average) than LAB. Similar CP concentrations of both populations were observed, except a higher concentration in SAB than in LAB in Experiment 3. A consistent (in Experiment 4 only as tendency) higher AA-N/total N ratio (on average 17.5%) was observed in SAB than in LAB. The 15N enrichment in SAB was systematically lower than in LAB. On the basis of the results of all studies a close relationship was found between the 15N enrichment in SAB and LAB, which was shown irrespective of experiments. This relationship was established from Experiments 1 and 2 and the above cited previous results (n = 20; P < 0.001; R 2 = 0.996), and then confirmed from the results of Experiments 3 and 4. These relationships between SAB and LAB demonstrate that CP supply from SAB is underevaluated by, on average, 21.2% when LAB are used as the reference. This underevaluation was higher for true protein and even higher for the lipid supply (32.5% and 59.6%, respectively, as an average of the four experiments). Large differences in AA profile were observed between SAB and LAB. The prediction equation obtained using 15N as the marker may be used to correct the errors associated with the traditional use of LAB as the reference sample, and therefore to obtain more accurate estimates of the microbial nutrient supply to the ruminants. © Copyright The Animal Consortium 2011.Financial support was provided by the CICYT funded Projects
AGL 2001-3662, AGL 2005-01712 and AGL 2006-08300. Analyses of 15N isotope ratios were performed at the Servicio
Interdepartamental de Investigacio´ n, Universidad Auto´ noma de
Madrid, Spain.González, J.; Arroyo, J.; Ouarti, M.; Guevara-González, J.; Rodríguez, C.; Alvir, M.; Moya Salvador, VJ.... (2012). Composition of free and adherent ruminal bacteria: inaccuracyof the microbial nutrient supply estimates obtained using freebacteria as reference samples and 15N as the marker. Animal. 6(3):468-475. https://doi.org/10.1017/S17517311110018074684756
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