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A orillas de los ríos Guadalquivir (Baetis) y Genil (Singilis), en el triángulo formado por las capitales de tres conventus de la Bética, Hispalis, Corduba y Astigi, se extienden los restos arqueológicos de casi un centenar de alfarerías productoras de ánforas del tipo Dressel 20 (fig. 1). Durante los tres primeros siglos d.C., el aceite de oliva producido en el interior de la Bética se comercializaba con estas ánforas globulares que fueron exportadas masivamente a todo el Imperio romano, siendo particularmente abundantes en Roma y en el limes germano/británico.
Even though AA 7075 is an aluminum alloy with high mechanical properties, it is not often applied in manufacturing. This is so, because it is considered as very difficult to produce defect free welded joints. This is so, because this alloy has a tendency to hot cracking. The metallurgical problems that appear during welding of AA 7075 have not been fully solved but they have been reduced by applying alloys such as: 4043 and 5356 as filler metals. However, in literature there is little information about the metallurgical effects of these types of filler metals applied in arc welded joints of AA7075. This is especially true for Tungsten Inert gas welding. Therefore, this work is focused in comparing the microstructure and Vickers microhardness in weldments of AA 7075 with ER4043, ER5356 and AA7075 as filler metals. Besides, a set of welded joints with the three different filler metals were quenched after welding in order to modify the final microstructure. The results were evaluated by microstructural analysis focused on the Heat Affected Zone and Vickers microhardness and they were compared among them.
The Murcia Twin Registry (MTR) is the only population-based registry in Spain. Created in 2006, the registry has been growing more than a decade to become one of the references for twin research in the Mediterranean region. The MTR database currently comprises 3545 adult participants born between 1940 and 1977. It also holds a recently launched satellite registry of university students (N = 204). Along five waves of data collection, the registry has gathered questionnaire and anthropometric data, as well as biological samples. The MTR keeps its main research focus on health and health-related behaviors from a public health perspective. This includes lifestyle, health promotion, quality of life or environmental conditions. Future short-term development points to the expansion of the biobank and the continuation of the collection of longitudinal data.
In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee, along with a multidisciplinary group of experts and Canadian Epilepsy Alliance representatives, has developed a position statement about the use of medical cannabis for epilepsy. This article addresses the current Canadian legal framework, recent publications about its efficacy and safety profile, and our understanding of the clinical issues that should be considered when contemplating cannabis use for medical purposes.
This is a retrospective cohort study based on data from five nursing homes which aims to appraise how physical and cognitive characteristics of nursing home residents were associated with the use of restraints, and to provide information on their prevalence in Spain. The goal was to assess, in a visual way, the possible interactions between the nursing homes residents’ characteristics and their association with the use of restraints. Motivation, risk factors, characteristics of the residents analysed by validated rating systems that assess mobility, level of dependence, cognitive condition and nutritional status, and their association with the use of restraints, were described by means of linear and non-linear multivariate approaches in the form of self-organised maps. Findings showed that the prevalence of restraints was high when compared to other developed countries. The visual analysis reinforced the knowledge that a greater impairment was associated with the use of restraints and vice versa. However, the residents’ characteristics were not always associated with the use of restraints. Subjective factors seem to play a relevant role in decision-making, so it is important to assess risk factors continuously and determine the actual need for the use of restraints from an individual perspective by basing the criteria on specific objectives, and on consistent, reproducible and reliable methods. Initiatives to minimise these subjective factors should be promoted. Likewise, a clear definition of physical restraints should be offered at each centre. In addition, effective legislation that clearly states the need, alternatives and motivation for the use of restraints is needed.
Species distribution models (SDMs) are statistical tools used to develop continuous predictions of species occurrence. ‘Integrated SDMs’ (ISDMs) are an elaboration of this approach with potential advantages that allow for the dual use of opportunistically collected presence-only data and site-occupancy data from planned surveys. These models also account for survey bias and imperfect detection through the use of a hierarchical modelling framework that separately estimates the species–environment response and detection process. This is particularly helpful for conservation applications and predictions for rare species, where data are often limited and prediction errors may have significant management consequences. Despite this potential importance, ISDMs remain largely untested under a variety of scenarios. We performed an exploration of key modelling decisions and assumptions on an ISDM using the endangered Baird’s tapir (Tapirus bairdii) as a test species. We found that site area had the strongest effect on the magnitude of population estimates and underlying intensity surface and was driven by estimates of model intercepts. Selecting a site area that accounted for the individual movements of the species within an average home range led to population estimates that coincided with expert estimates. ISDMs that do not account for the individual movements of species will likely lead to less accurate estimates of species intensity (number of individuals per unit area) and thus overall population estimates. This bias could be severe and highly detrimental to conservation actions if uninformed ISDMs are used to estimate global populations of threatened and data-deficient species, particularly those that lack natural history and movement information. However, the ISDM was consistently the most accurate model compared to other approaches, which demonstrates the importance of this new modelling framework and the ability to combine opportunistic data with systematic survey data. Thus, we recommend researchers use ISDMs with conservative movement information when estimating population sizes of rare and data-deficient species. ISDMs could be improved by using a similar parameterization to spatial capture–recapture models that explicitly incorporate animal movement as a model parameter, which would further remove the need for spatial subsampling prior to implementation.
This article deals with the trade of local merchandise in Santiago's district (Corregimiento) from 1773 to 1778, based on tributary sources. It contributes to the debate on the organization of the colonial internal market. The main traded merchandise, which represented about 80% of Chilean exports, came from the cattle exploitation that was developed in the haciendas around Santiago, whose cattle stocks were complemented from neighboring provinces in the Andes. The largest destination of this trade, in which big merchants acted together with a thousand minor merchants, were the retail channels and the artisan sectors supplying the population of Santiago. The impulse of this demand on the domestic market was so dynamic that it shows a degree of regional autonomy higher than what it is traditionally assumed for the Chilean economy in the late colonial period.
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.
A 6–18 GHz high-power amplifier (HPA) design in GaN on SiC technology is presented. This power amplifier consists of a two-stage corporate amplifier with two and four transistors, respectively. It has been fabricated on UMS using their 0.25 µm gate length process, GH25. A study of the suitable attachment method and measurement on wafer and on jig are detailed. This HPA exhibits an averaged output power of 39.2 dBm with a mean gain of 11 dB in saturation and a 24.5% maximum power added efficiency in pulse mode operation with a duty cycle of 10% with a 25 µs pulse width.
Venezuela has plunged into a humanitarian, economic, and health crisis of extraordinary proportions. This complex situation is derived from dismantling of structures at the institutional, legal, political, social, and economic level affecting the life and wellbeing of the entire population.
This study aims to assess the impact of Venezuela’s healthcare crisis on vector-borne and vaccine-preventable diseases and the spillover to neighboring countries.
Since October 2014, there is a paucity of official epidemiological information in Venezuela. An active search of published and unpublished data was performed. Venezuela and Latin America data were sourced from PAHO Malaria Surveillance and from Observatorio Venezolano de la Salud. Brazil and Colombian data were accessed via their respective Ministries of Health.
Economic and political mismanagement have precipitated a general collapse of Venezuela’s health system with hyperinflation rates above 45,000%, people impoverishment, and long-term shortages of essential medicines and medical supplies. In this context, the rapid resurgence of previously well-controlled diseases, such as vaccine-preventable (measles, diphtheria) and arthropod-borne (malaria, dengue) diseases has turned them into epidemics of unprecedented magnitudes. Between 2000-2015 Venezuela witnessed a 365% increase in malaria cases followed by a 68% increase (319,765 cases) in late 2017. The latest figures have surpassed 600,000 malaria cases with a prediction to reach 1 million by the end of 2018. Measles and diphtheria have recently re-emerged after a progressive interruption of the national immunization program, with vulnerable indigenous population being particularly affected. In response to Venezuela’s rapidly decaying situation, a massive population exodus is ongoing towards neighboring countries causing a spillover of diseases.
Action to halt the spread of vaccine-preventable diseases within Venezuela is a matter of urgency for the country and the region. Global and hemispheric health authorities should urge the Venezuelan government to allow establishing a humanitarian channel to bring relief.