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We study the extent to which centralized democratic institutions enhance collective action under political accountability. In a public goods game with costly punishment, we vary the appointment of one group member to enforce punishment. Specifically, we compare democratically elected punishers to those appointed exogenously, under both single- and multiple-selection environments. We find that democratically appointed sanctioning authority has muted effects on group outcomes; yet, they contribute as much as other group members when facing repeated elections, as opposed to the ones in single selection or exogenously appointed. One important feature of modern governance to discipline authorities is political accountability; when in place, it offers different incentives, and in particular, we observe a responsibility effect reflected in higher contribution behavior. Important in our study results, this effect rises only under a democracy.
Multiform glioblastoma (MG) represents 70% of all gliomas, with half of patients older than 65 years with median survival of 12–18 months, hypofractionation seeks to reduce the intensity and duration of treatment without impacting on survival rates. The objective was to determine the global survival and recurrence-free survival of adults over 70 years old with MG treated with hypofractionated radiotherapy and standard scheme. The review of patients older than 70 years treated with radiotherapy from 2013 to 2016 was performed.
Twenty-four patients were analysed, with a median follow-up of 239 days, and there is no difference in overall survival 12·3 versus 10·5 months (p = 0·55) and recurrence-free survival 8·3 versus 3·4 months (p = 0·48) between both schemes, conventional versus hypofractioanted, respectively.
The results in this study show that hypofractionated scheme could be comparable in overall survival and recurrence-free survival to conventional fractionation, but a longer patients’ trial should be done.
Consumer preferences are likely to become more important in policy and market initiatives in developing countries. This study explores current and potential demand for high-quality beef in Ecuador. A survey of 547 households (including two choice experiments) was carried out in order to gather knowledge, quality perceptions, and experiences regarding Ecuadorian beef and preferences for specific beef attributes. Consumers have positive and economically significant willingness-to-pay values for all credence attributes considered in the study: sanitary control, meat maturation, animal welfare, and traceability. The results provide evidence that there is a potential market for increased-quality beef in Ecuador.
Ceramic–metal composites are an important group of materials that have gained interest recently because of their peculiar properties. There have been numerous studies on the reinforcement of alumina through the incorporation of various ductile metals in it. However, these studies have been limited to determining the effect of the addition of metals on the mechanical properties of ceramics, without determining the effect of these metal additions on other physical properties of the resulting composite. In this way, in agreement with the obtained results, we have that because of the conductive nature of metals, there is a considerable decrease in the electrical resistivity of alumina, mainly when copper is added to it. However, in terms of optical performance, alumina matrix composites showed significant changes in absorbance in the visible spectra. The addition of iron, titanium, and yttrium enhanced the absorbance of alumina, whereas manganese addition significantly decreased the optical absorption.
In recent years, modified graphene has been used in various biomedical applications due to its excellent properties that allow the development of devices capable of detecting macromolecules within the human organism, also for biomolecular analysis, discovery of biomarkers, bioimaging and target delivery. These applications involve interactions between enzymes, proteins, peptides, DNA, RNA, etc. and modified graphene, therefore the study and the theoretical and experimental investigation of these interactions is essential for the development of nanobio-technology. For example, many applications based on using modified graphene to detect macromolecules require studying the changes in the properties of doped graphene when interacting with macromolecules. In this work, DFT and molecular dynamics methods were used to obtain results of the changes in energy density of states of graphene doped with iron when it is made to interact with coenzyme A. Besides, we presented a study of molecular dynamics in order to determine the quantum factors that guide the interaction graphene-coenzyme A. The system was studied in aqueous medium which it was simulated by the dielectric constant of water. The results confirm that the methodology presented in this work can be used to theoretically detect various macromolecules.
Boosted by landmark decisions such as Crotty, Solange, or Maastricht-Urteil, academic literature on National Higher Courts in the context of European integration has undergone an exponential growth in the last decades. In this Article, I aim at mapping this emerging subfield in order to explore the three patterns that structure it. First, a trend towards the consolidation and expansion of literature on the higher courts of the Member States, which has gained relative autonomy from general studies on European law and politics. Second, a clear tendency towards the internationalization of this subfield, which has developed in parallel to the national scholarship on the topic. And third, the emergence of a pattern of transdisciplinary dialogue in a subfield featured by the diversity of approaches, methodologies, and epistemological backgrounds.
The Endangered Cuvier's gazelle Gazella cuvieri is an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2 in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.
The cattle tick Rhipicephalus (Boophilus) microplus is a hematophagous ectoparasite of major importance for the livestock industry. It shows a remarkable ability to survive over long periods without feeding. However, the mechanisms used to endure long-term starvation are poorly understood. It is believed that autophagy, a process of intracellular protein degradation, may play a significant role to confront adverse environmental conditions. To advance our understanding of autophagy in R. microplus, in the present study we report the molecular characterization of three autophagy-related (ATG) genes, namely, RmATG3, RmATG4 and RmATG6, as well as their expression profiles in different developmental stages and organs of the parasite. The deduced amino acid sequences derived from the characterized gene sequences were subjected to Basic Local Alignment Search Tool analysis. The testing produced significant alignments with respective ATG proteins from Haemaphysalis longicornis and Ixodes scapularis ticks. Real-time polymerase chain reaction assays revealed that RmATG4 and RmATG6 transcripts were elevated in egg and ovary tissue, when compared with larva and midgut samples, while RmATG3 expression in midgut was 2-fold higher than in egg, larva and ovary samples.
Agriculture in the Altiplano and Andean Mountains is experiencing threats to sustainability mainly due to intensive cultivation of quinoa driven by international markets. This recent export-oriented production system is causing the degradation of soils and reducing productivity, therefore, agro-technological innovations are necessary to sustain cropping systems while maintaining organic quality (mostly quinoa). In this work, we searched for native Trichoderma species associated with plants from the Andean highlands to obtain an environmentally friendly and organic alternative to chemical fertilizers. We obtained different Trichoderma isolates from quinoa, potato and maize roots and soil, which were identified as Trichoderma harzianum, as well as other species. Twelve of the isolates were cultured in pairs to stimulate the production and secretion of compounds of diverse chemical nature that we called collectively ‘secondary metabolites’ (SMs). Crude extracts of SMs were used to inoculate selected crops to determine their plant growth promoting potential compared with two commercially available controls, chemical fertilizer and a bio-fertilizer. Results showed that SMs significantly promoted lettuce and radish growth and increased quinoa grain yield. Indole acetic acid was detected in all SM extracts that promoted plant growth, suggesting that this plant regulator might be responsible for the plant growth promoting activity. In conclusion, the Trichoderma-derived SMs approach appears to be a promising, simple and accessible technology for small-scale farmers in order to insure the sustainability, affordability and accessibility of food production in the Andes.
The monitoring of corrosion in reinforced concrete structures is considered an important preventive factor against the corrosive damage. The present paper shows the design and construction of a device which performs remote measurements of the polarization resistance of reinforcing steel, this was made using the electrochemical technique of linear polarization resistance as a method to obtain the information of the corrosive process. The development was carried out by implementing a potentiostat based on a free development platform. The design allows to store all the data on a physical memory and to send the results through the mobile network to a web server, where the measured values can be analyzed using an internet connection.
The linear polarization resistance measurements were made in cylindrical concrete specimens with rebars of ½ ”, each one instrumented with embedded electrodes of Copper/Copper sulfate and graphite. The specimens were subjected to a saturated environment of chlorides (3.5%) where the corrosive process was monitored with the developed system. The results were compared with tests performed on a commercial potentiostat / galvanostat, where the values obtained have an mean of 4.83%.
Bacteriocins are natural compounds used as food biopreservatives instead of chemical preservatives. Bifidobacterium animalis subsp. lactis (Bifid. lactis) was shown to produce a bacteriocin-like inhibitory substance (BLIS) able to inhibit the growth of Listeria monocytogenes selected as an indicator microorganism. To enhance this production by the strain Bifid. lactis BL 04, skim milk (SM) was used as a fermentation medium either in the presence or in the absence of yeast extract, Tween 80 or inulin as stimulating additives, and the results in terms of bacterial growth and BLIS production were compared with those obtained in a traditional high cost complex medium such as Man, Rogosa and Sharpe (MRS). To this purpose, all the cultivations were carried out in flasks at 200 rpm under anaerobic conditions ensured by a nitrogen flowrate of 1·0 L/min for 48 h, and BLIS production was quantified by means of a modified agar diffusion assay at low values of both temperature and concentration of List. monocytogenes. Although all these ingredients were shown to exert positive influence on BLIS production in both media, yeast extract and SM were by far the best ingredient and the best medium, respectively, allowing for a BLIS production at the late exponential phase of 2000 AU/ml.
This paper introduces a novel 6-DOF parallel manipulator, which is composed of two 3-RUS parallel manipulators that share a common three-dimensional moving platform. Semi-analytical form solutions are easily obtained to solve the forward displacement analysis of the robot using the non-planar geometry of the moving platform, whereas the velocity, acceleration, and singularity analyses are performed using screw theory. A case study is included to show the application of the kinematic model, which is verified with the aid of a commercially available software. Simple kinematic analysis and reduced singular regions are the main benefits of the proposed parallel manipulator.
The Memory Characteristics Questionnaire (MCQ) was developed by Johnson, Foley, Suengas, and Raye (1988) to assess the characteristics of memories of external and internal origin, postulated in the source monitoring model (Johnson, Hashtroudi, & Lindsay, 1993). The MCQ was translated into Spanish using a back-translation method. Psychometric properties of the translated MCQ were tested using responses collected from an experimental study simulating a forensic context. Ten police officers and 8 psychologists individually interviewed 240 university students who completed the MCQ after reporting what they had seen in a film. Half of the participants were asked to tell the truth, while the other half were asked to lie. The results have shown adequate psychometric properties of the Spanish MCQ items for the total sample and across experimental conditions. Cronbach’s alpha value was .79 for the total sample, .78 for the honest condition, and .76 for the lie condition. Validity evidence of dimensionality supports that the factor structure of Spanish MCQ was equivalent to that proposed by the authors of the original version. Also, a two-factor ANOVA (video clip x condition) was performed to analyze experimental data. Neither interaction effects, F(236) = 1.189; p = .277, nor main effects were found to be significant between those asked to tell the truth and those asked to lie. These results demonstrate that the Spanish MCQ has adequate psychometric properties.
The catalytic activity of disordered binary alloy metal surfaces is investigated for the oxygen reduction reaction (ORR) by generating free energy diagrams and performing calculations on d-band centers of alloys. The disorder was simulated using virtual crystal approximation; then, based on periodic, self-consistent density functional theory (DFT) methods, we calculated adsorption energies of reaction intermediates. Alternative pathway for ORR mechanism, involving proton/electron transfer to adsorbed oxygen and hydroxyl, is considered. The methodology was applied to (111) surface of PdxCu1-x disordered binary alloys, with different values of x concentration. This study found that at the ORR equilibrium potential of 1.23 V, the reactivity of all surfaces is shown to be limited by the rate of OH removal from the surface. Among the surfaces studied, the surface of Pd0.80Cu0.20 shows the highest reactivity and is more active than other non-Pt alloys. These results are in excellent agreement with earlier experimental and theoretical work.
Radiocarbon decay is rarely used to assess the residence time of modern groundwater due to the low resolution of its long half-life in comparison to the expected range of ages. Nonetheless, the modern 14C peak induced by the nuclear bomb tests traces efficiently the impacts of recent human activities on groundwater recharge, as well as for tritium. A simple lumped parameter model (LPM) was implemented in order to assess the interest of 14C and 3H nuclear peaks in a highly anthropized aquifer system of southeastern Spain under intense agricultural development. It required i) to assess a correction factor for modern 14C activities and ii) to reconstruct the 3H recharge input function, affected by irrigation. In such a complex hydrogeological context, an exponential model did not provide satisfying results for all samples. A better solution was reached by taking into account the qualitative recent variation of the recharge rates into a combined exponential flow and piston flow model. Apart from presenting an uncommon approach for 14C dating of modern groundwater, this study highlights the need of considering not only the variation of the tracer but also the variability of recharge rates in LPMs.
Based on Basic Needs Theory, one of the mini-theories of Self-determination Theory (Ryan & Deci, 2002), the present study had two objectives: (a) to test a model in the Mexican sport context based on the following sequence: perceived coach autonomy support, basic psychological needs satisfaction, and psychological well-being, and b) to analyze the mediational effect of the satisfaction of perceived coach autonomy support on indicators of psychological well-being (satisfaction with life and subjective vitality). Six hundred and sixty-nine young Mexican athletes (Boys = 339; Girls = 330; Mage = 13.95) filled out a questionnaire assessing the study variables. Structural equations analyses revealed that perceived coach autonomy support predicted satisfaction of the basic psychological needs for autonomy, competence, and relatedness. Furthermore, basic need satisfaction predicted subjective vitality and satisfaction with life. Autonomy, competence and relatedness partially mediated the path from perceived coach autonomy support to psychological well-being in young Mexican athletes.