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We present a novel Ti64/20Ag highly porous composite fabricated by powder metallurgy for biomedical applications and provide an insight into its microstructure and mechanical proprieties. In this work, the Ti64/20Ag highly porous composites were successfully fabricated by the space holder technique and consolidated by liquid phase sintering, at lower temperatures than the ones used for Ti64 materials. The sintering densification was evaluated by dilatometry tests and the microstructural characterization and porosity features were determined by scanning electron microscopy and computed microtomography. Permeability was estimated by numerical simulations on the 3D real microstructure. Mechanical properties were evaluated by simple compression tests. Densification was achieved by interparticle pore filling with liquid Ag that does not drain to the large pores, with additional densification due to the macroscopical deformation of large pores. Pore characteristics are closely linked to the pore formers and the permeability was highly increased by increasing the pore volume fraction, mainly because the connectivity was improved. As expected, with the increase in porosity, the mechanical properties decreased. These results permitted us to gain a greater understanding of the microstructure and to confirm that we developed a promising Ti64/20Ag composite, showing E of 7.4 GPa, σy of 123 MPa and permeability of 3.93 × 10−11 m2. Enhanced adaptability and antibacterial proprieties due to Ag were obtained for bone implant applications. [ABSTRACT FROM AUTHOR]

The article present novel insights of the interplay between the distributions of facilities and population that maximize accessibility over the existing road networks. It mentions that travel costs could be reduced in half through redistributing facilities. It also mentions the average travel distance can be modeled as a functional form of the number of facilities and the population density.

Renewable biodiesel with a high content of n-C17 alkanes was prepared through the catalytic hydrodeoxygenation of oleic acid under optimum conditions of temperature, reaction time and weight percentage of Ni deposited in γ-Al2O3. The hydrotreated vegetable oil (HVO) was blended with petrodiesel (20 % and 40 % of HVO) to evaluate its behaviour in a diesel engine. Comparative studies of power and emission of atmospheric pollutants such as NOx, CO, HC and smoke were evaluated under prepared blends and petrodiesel. The presence of HVO biodiesel at full load generated a slight decrease in power compared to petrodiesel; however, the decrease in emission of pollutants when using the blends containing HVO was significant. In the case of 40 % HVO were able to reduce more of 20 % of CO and HC emissions, and more than 40 % reduction in smoke when compared with petrodiesel. The NOx emissions of the blends with HVO had a significant slightly decrease. Further, the properties of Ni/γ-Al2O3 catalysts are justified by the results of EDS characterization, surface area (SBET), XRD, XPS, HR-TEM and it's capacity to produce biodiesel. [ABSTRACT FROM AUTHOR]

This paper provides a new methodology to compute a reduced but efficient set of candidate lines in a transmission expansion planning (TEP) context. Considering this reduced set of candidate lines should lead to similar investment decisions as if all the possible ac and dc candidate lines that could be installed in the network were considered. A first “hybrid” relaxed TEP problem is solved. Based on this initial solution, a new relaxed TEP problem is iteratively solved in which the dc load flow (DCLF) model is enforced to a certain extent in the partially expanded ac corridors. Once a convergence threshold has been reached, an upper bound of the number of candidate ac and dc lines to install in each corridor can be defined. This process results in a compact search space. Our algorithm has been implemented in General Algebraic Modeling Software (GAMS) and has been tested on a case study based on the European power system. The method produces very promising results and in the considered case study, leads to a very efficient investment. [ABSTRACT FROM AUTHOR]

Background: Although both hospitalization and mortality due to heart failure (HF) have been widely studied, less is known about the impact of HF on disability and quality of life.Aim: To assess the degree of disability and quality of life in HF patients attended at family medicine centres.Design and Setting: Cross-sectional study of a cohort of HF patients attended at family medicine centres.Methods: Disability was assessed with the WHODAS 2 questionnaire, which provides a global and six domain scores that is understanding and communication, getting around, self-care, getting along with people, life activities and participation in society. Quality of life was assessed with the Minnesota Living with Heart Failure Questionnaire, which furnishes a global and two domain scores, physical and emotional.Results: A breakdown of the results showed that 28% of patients had moderate disability and 16.7% had severe disability, with the most important areas affected being: life activities, 8.9% extreme disability and 30.3% severe disability; getting around, 34.6% severe disability and 2% extreme disability; and participation in society, 53.3% moderate-severe disability. Quality of life was mildly affected. New York Heart Association (NYHA) Functional Classification and sex were the major determinants of disability and quality of life. Angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists were associated with better scores in the "getting around" and "life activity" domains.Conclusion: HF patients in primary care show an important degree of disability and an acceptable quality of life. [ABSTRACT FROM AUTHOR]

Background: Heart failure (HF) is the leading cause of hospitalization in people over age 65. Predictive hospital admission models have been developed to help reduce the number of these patients. Aim: To develop and internally validate a model to predict hospital admission in one-year for any non-programmed cause in heart failure patients receiving primary care treatment. Design and setting: Cohort study, prospective. Patients treated in family medicine clinics. Methods: Logistic regression analysis was used to estimate the association between the predictors and the outcome, i.e. unplanned hospitalization over a 12-month period. The predictive model was built in several steps. The initial examination included a set of 31 predictors. Bootstrapping was used for internal validation. Results: The study included 251 patients, 64 (25.5%) of whom were admitted to hospital for some unplanned cause over the 12 months following their date of inclusion in the study. Four predictive variables of hospitalization were identified: NYHA class III-IV, OR (95% CI) 2.46 (1.23–4.91); diabetes OR (95% CI) 1.94 (1.05–3.58); COPD OR (95% CI) 3.17 (1.45–6.94); MLHFQ Emotional OR (95% CI) 1.07 (1.02–1.12). AUC 0.723; R2N 0.17; Hosmer-Lemeshow 0.815. Internal validation AUC 0.706.; R2N 0.134 Conclusion: This is a simple model to predict hospitalization over a 12-month period based on four variables: NYHA functional class, diabetes, COPD and the emotional dimension of the MLHFQ scale. It has an acceptable discriminative capacity enabling the identification of patients at risk of hospitalization. [ABSTRACT FROM AUTHOR]

Stories of mega-jams that last tens of hours or even days appear not only in fiction but also in reality. In this context, it is important to characterize the collapse of the network, defined as the transition from a characteristic travel time to orders of magnitude longer for the same distance traveled. In this multicity study, we unravel this complex phenomenon under various conditions of demand and translate it to the travel time of the individual drivers. First, we start with the current conditions, showing that there is a characteristic time τ that takes a representative group of commuters to arrive at their destinations once their maximum density has been reached. While this time differs from city to city, it can be explained by Γ, defined as the ratio of the vehicle miles traveled to the total vehicle distance the road network can support per hour. Modifying Γ can improve τ and directly inform planning and infrastructure interventions. In this study we focus on measuring the vulnerability of the system by increasing the volume of cars in the network, keeping the road capacity and the empirical spatial dynamics from origins to destinations unchanged. We identify three states of urban traffic, separated by two distinctive transitions. The first one describes the appearance of the first bottlenecks and the second one the collapse of the system. This collapse is marked by a given number of commuters in each city and it is formally characterized by a nonequilibrium phase transition. [ABSTRACT FROM AUTHOR]

This paper provides a new methodology to compute a reduced but accurate network representation in a transmission expansion planning (TEP) context. Considering this reduced network should lead to the same investment decisions as if the whole original network were considered. A set of relevant lines to be preserved is defined based on a proxy of the TEP solution. An optimal network partition, resulting from solving the multicut problem, is computed in such a way that the two ends of each of these relevant lines are allocated to two different areas. An iterative Kron reduction is then applied to each area to eliminate most of the buses that are not connected to any interarea line. This two-step process results in a compact but representative reduced network. Our algorithm has been implemented in General Algebraic Modelling Software and Matrix Laboratory and has been tested on the standard IEEE 118 bus system and a case study based on the European power system. The method produces very promising results and, in the considered case studies, leads to the same, or equally efficient, investment decisions and essentially the same total costs as when considering the whole original network. [ABSTRACT FROM AUTHOR]

The trans-esterification and esterification of waste vegetable oil mainly under sub-critical temperature of methanol in the presence of sulfonated char were achieved. The carbonaceous materials were analyzed by means of various physical and chemical techniques such as Raman spectroscopy, X-ray diffractometry, temperature programmed desorption and X-ray photoelectrons spectroscopy. The carbon-based large-acidity catalyst showed good chemical and thermal properties and a high performance in the production of methyl esters from waste vegetable oil, which was easily separated from the liquid mixture. A temperature of 210°C, reaction time of 20 min and a catalyst amount of 0.03 g were the optimal experimental conditions for the trans-esterification of the vegetable oil with methanol giving a conversion to triglycerides of 96.5% according to the response surface methodology. The design of experiments type Box-Behnken was successfully applied to study effects of the parameters in the production of biodiesel and it presented optimal conditions for maximum performance with values near to those experimentally found. The catalyst was recovered from the final mixture by filtration and reused without regeneration showing a catalytic activity stable up to 4 or more reaction cycles. [ABSTRACT FROM AUTHOR]

This paper provides a novel technique to represent in a reduced, or compact, way temporal variability in transmission expansion planning (TEP). This reduction is handled by means of “snapshot selection.” Instead of taking into account all the possible operational states and their associated optimal power flow, a reduced group of them is selected that is representative of all the states that should have an influence on investment decisions. Considering this reduced group of operational states should lead to the same investment decisions as if all the snapshots in the target year were considered. Original operational states are compared in the space of the benefits produced by potential reinforcements considered, which are relevant drivers for investment decisions. The benefits produced by these potential reinforcements are computed based on the incremental change in operation costs resulting from their installation. A clustering algorithm is used to group together those operational states where similar line benefits are realized. Our algorithm has been tested on a modified version of the standard IEEE 24 bus system. The method produces promising results and proves to be more efficient than other snapshot selection methods used until now in computing an accurate enough selection of snapshots representing system operation variability in TEP. [ABSTRACT FROM AUTHOR]

The objective of this paper is to propose a novel methodology to compute the benefit obtained by the individual transmission network users from each of the transmission expansion projects within an expansion plan. The benefits computed should be coherent with the technical and economic principles that underlie the development of the expansion plan. Thus, this methodology is based on the idea that the benefits produced by each project of a plan should be determined considering all projects jointly, instead of individually. Some benefits obtained by users from projects evolve continuously with the deployment of the expansion plan, while others are discrete, since they occur at certain points of the deployment of this plan. A separate Aumann-Shapley game is solved to allocate continuous benefits, and each discrete one. In the second case, the standard Aumann-Shapley algorithm for the allocation of benefits is modified to cope with the fact that the function of each user’s benefits is not continuous with the size of projects deployed. Two case studies are used to compare the methodology proposed with existing ones and demonstrate its applicability to real-life decision making processes. The results show that the methodology proposed is able to overcome problems detected in other methodologies, providing more accurate and sound results. The good properties of the methodology proposed make it applicable to problems related to network expansion regulation, such as the cost allocation of new investments. Although the methodology proposed is particularized to electric power systems, its concept and fundamentals can also be applied in other energy sectors, such as gas. [ABSTRACT FROM AUTHOR]

Transmission charges aim to recover the cost of transmission network investments and provide efficient locational signals to new generators. In this paper, we investigate the effect of these charges on the development of new generation capacities in the system. Generation expansion planning is decided by strategic generation planners (SGPs) trying to maximize their profits, while transmission line investments are planned by a central planner and regulatory body aimed at minimizing the overall operation and network investment costs of the system. Regulatory transmission charges (RTCs) are calculated according to the marginal responsibility of generation investment on transmission network investment costs. An iterative algorithm is proposed to model the interaction taking place between the central planner and SGPs. The developed methodology is applied to a 2-node illustrative example and the IEEE-RTS96, and effects of RTCs on investment decisions of SGPs are analyzed. [ABSTRACT FROM AUTHOR]

This paper proposes a novel methodology to estimate the benefits produced by transmission expansion projects that are part of an expansion plan. Any methodology applied should be coherent with the technical and economic principles that underlie an efficient planning of the network expansion, where expansion projects are selected to be part of the plan according to the benefit they produce when considered jointly with the rest of projects. The methodology developed is based on the idea that projects to be undertaken should be evaluated jointly, instead of individually, because the benefits produced by each of them depend on other projects in the plan. We formulate a cooperative game to allocate the benefits of the plan to individual projects using the Aumann-Shapley concept. Then, players in the game are expansion projects. The method proposed is able to capture interactions among projects. Moreover, it is highly computationally efficient and therefore can be applied to real –large– expansion plans. Two case studies are used to compare the performance of the methodology proposed to that of existing methods. The results show that the proposed methodology provides regulatory authorities with the most relevant information for the identification of high-priority expansion projects. [ABSTRACT FROM AUTHOR]

This paper presents a cost-based TSO-DSO coordination model to quantify the value of local flexibility services and analyze its impact on the transmission grid expansion and the system operation. Flexibility is provided to the DC power flow transmission grid model by microgrids within the integrated AC power flow distribution grid model. The model's objective is to minimize the overall cost of transmission investments and procured flexibility and is achieved using a bilevel optimization approach where the power exchanges on all connected grid interfaces are controlled. Case studies using a combined test system of the IEEE RTS-96 transmission network interfacing multiple 33-bus distribution grids were performed to validate the model and assess the values and impacts of local flexibility on the transmission system expansion. The results showed that the proposed model modified the investment plan and dispatch of flexibility resources reducing the investment and operation cost of the transmission system. • A TSO-DSO-MG coordination framework to assess the value of local flexibility. • Local flexibility services FS-B & FS-C were incorporated in TSO's investment plan. • A leader and multi-follower bilevel formulation of the TSO-DSO-MG coordination. • FS-C could benefit all connected systems depending on the chosen capacity limit. • FS-B reduced the TSO's total cost, leaving the other costs unaffected. [ABSTRACT FROM AUTHOR]

Intraday markets can be organized as continuous trading or discrete auction sessions. While many studies have attempted to compare the liquidity of these two models, additional external factors specific to each system, such as the balancing market design and number of bidding zones, affect overall market liquidity. In this regard, the Spanish hybrid intraday markets seem like an excellent case study to compare the two market models. Since the two intraday models are implemented in the same system (the Spanish one), the same conditions apply to their implementation. However, a direct comparison of liquidity is still challenging due to two factors: (1) differences exist in market architecture (timing, pricing scheme, bidding formats, etc.) between the two models, which create preferences among market players for one or the other; (2) the opportunistic behavior of market players in the system responding to the market price signals may affect the liquidity dynamics. We demonstrate the relevance of these two factors coming into play in the Spanish intraday markets, first carrying out a qualitative analysis of the market architecture of both models and then empirically analyzing a market manipulation attempt, which we refer to as the 15:10 rush. Our analysis points towards the need for more efficient regulation governing the interaction of the continuous intraday market with intraday auction markets and the potential risks from increased algorithmic trading. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease mainly affects the elderly population causing a progressive functional disability with motor, psychic, and cognitive deterioration. Objective: This study was carried out to evaluate disability caused by Parkinson's disease by analyzing the median time to reach Hoehn and Yahr stage III and to investigate predictor variables based on a 20-year longitudinal follow-up study. Methods: We examined 273 patients with Parkinson's disease recruited between 1978 and 1998. We performed a survival analysis using the Kaplan-Meier method to determine the time to disability and we used a Cox regression model to adjust prognosis factors. Results: The median time to reach Hoehn and Yahr stage III was 7.73 years (95% CI: 5.95-8.05). Independent predictors of disability were: age at onset, the hazard ratio (HR) = 1.10, 95% CI: 1.08-1.12; UPDRS II (activities of daily living) HR = 1.08, 95% CI: 1.03-1.14; and akinesia and rigidity at onset HR = 1.55, 95% CI: 1.07-2.24. Conclusions: Patients with Parkinson's disease evolve gradually toward disability, and prognostic factors of this evolution were identified. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The aim of the present work is to evaluate the activation energy (Ea) at different cathodic overpotentials (η) by potentiodynamic tests which were carried out at different temperatures of Ni-based, NiCr-m, and NiCr-p porous electrodes, during the alkaline electrolysis processes. On the other hand, the electrochemical stability of the electrodes was evaluated by cyclic voltammetry after 1000 cycles of operation and by potentiostatic tests after 10 h at −1.5 V vs. SCE. The electrodes were sintered with a heating rate of 25 °C/min up to a temperature of 1000 °C (Ni-based and NiCr-m) and 1200 °C (NiCr-p) for 60 min. The results showed that the Ea value was lower for the Ni-based system at equilibrium; however, the NiCr-p electrode had a better performance due to higher negative apparent Ea values as a function of η (dEa/dη). The cyclic voltammetry tests suggest that the NiCr-p electrode improves its activity by about 71% in its long-term operation in comparison with Ni-based and NiCr-m. A similar behavior was observed in the potentiostatic test which showed a higher cathodic current density associated with a charge transfer process after 10 h. The higher stability of the NiCr-p is attributed to a homogeneous Cr distribution in the nickel matrix. [ABSTRACT FROM AUTHOR]

Evolution of the inner microstructure of uniaxially pressed copper powders was investigated by in situ X-ray microtomography. Experiments were carried out at the European Synchrotron in Grenoble, France. Sintering was performed under reducing atmosphere at 1050 °C. Qualitative and quantitative information from the 3D images acquired along the whole sintering cycle were analyzed. From that, macro- and microstructural features of the evolving microstructure were obtained. We found that large pores can be created during sintering and then they can grow during the whole thermal cycle by reducing the initial relative density of the sample by 10 %. The effect of the pore shape and the heterogeneous distribution of the pore volume fraction inside the sample are responsible for the behavior observed during sintering. The heterogeneous deformation measured is controlled by the evolution of the porosity. [ABSTRACT FROM AUTHOR]

Background: In order to ensure proper management of primary care (PC) services, the efficiency of the health professionals tasked with such services must be known. Patients with heart failure (HF) are characterized by advanced age, high co-morbidity and high resource utilization.Objective: To ascertain PC resource utilization by HF patients and variability in the management of such patients by GPs.Methods: Descriptive, cross-sectional study targeting a population attended by 129 GPs over the course of 1 year. All patients with diagnosis of HF in their clinical histories were included, classified using the Adjusted Clinical Group system and then grouped into six resource utilization bands (RUBs). Resource utilization and Efficiency Index were both calculated.Results: One hundred per cent of patients with HF were ranked in RUBs 3, 4 and 5. The highest GP visit rate was 20 and the lowest in excess of 10 visits per year. Prescription drug costs for these patients ranged from €885 to €1422 per patient per year. Health professional efficiency varied notably, even after adjustment for co-morbidity (Efficiency Index Variation Ratio of 28.27 for visits and 404.29 for prescription drug cost).Conclusions: Patients with HF register a high utilization of resources, and there is great variability in the management of such patients by health professionals, which cannot be accounted for by the degree of case complexity. [ABSTRACT FROM AUTHOR]

Background. In order to ensure proper management of primary care (PC) services, the efficiency of the health professionals tasked with such services must be known. Patients with heart failure (HF) are characterized by advanced age, high co-morbidity and high resource utilization. Objective. To ascertain PC resource utilization by HF patients and variability in the management of such patients by GPs. Methods. Descriptive, cross-sectional study targeting a population attended by 129 GPs over the course of 1 year. All patients with diagnosis of HF in their clinical histories were included, classified using the Adjusted Clinical Group system and then grouped into six resource utilization bands (RUBs). Resource utilization and Efficiency Index were both calculated. Results. One hundred per cent of patients with HF were ranked in RUBs 3, 4 and 5. The highest GP visit rate was 20 and the lowest in excess of 10 visits per year. Prescription drug costs for these patients ranged from €885 to €1422 per patient per year. Health professional efficiency varied notably, even after adjustment for co-morbidity (Efficiency Index Variation Ratio of 28.27 for visits and 404.29 for prescription drug cost). Conclusions. Patients with HF register a high utilization of resources, and there is great variability in the management of such patients by health professionals, which cannot be accounted for by the degree of case complexity. [ABSTRACT FROM AUTHOR]

The marginal value of transmission lines in the dispatch is widely used in the literature and has relevant practical applications related to planning the expansion of the transmission grid and computing the remuneration of merchant lines. This paper presents a general formulation of the marginal value of a line in the dispatch that highlights the dependence of this value on the link between line admittance and capacity. We discuss the value of a line according to marginal principles following a general approach and prove that only if the admittance of a line can be expressed as a linear function of its capacity, or when admittance and capacity can be deemed independent, is this value equal to the product of the difference between marginal electricity prices at both ends of the line and the flow through this line. Afterwards, we show that under a set of stylized conditions the remuneration of efficient network investments according to their marginal value in the dispatch should result in an exact recovery of their cost. Finally, we compute the marginal value of lines in a stylized, though representative, system for several relationships between line capacities and admittances to illustrate the theoretical results obtained. [ABSTRACT FROM PUBLISHER]

Background: Chronic obstructive pulmonary disease (COPD) is frequent and often coexists with other diseases. The aim of this study was to quantify the prevalence of COPD and related chronic comorbidity among patients aged over 40 years visiting family practices in an area of Madrid. Methods: An observational, descriptive, cross-sectional study was conducted in a health area of the Madrid Autonomous Region (Comunidad Autónoma de Madrid). The practice population totalled 198,670 persons attended by 129 Family Physicians (FPs), and the study population was made up of persons over the age of 40 years drawn from this practice population. Patients were deemed to have COPD if this diagnosis appeared on their clinical histories. Prevalence of COPD; prevalence of a further 25 chronic diseases in patients with COPD; and standardised prevalence ratios, were calculated. Results: Prevalence of COPD in family medicine was 3.2% (95% CI 3.0--3.3) overall, 5.3% among men and 1.4% among women; 90% of patients presented with comorbidity, with a mean of 4 ± 2.04 chronic diseases per patient, with the most prevalent related diseases being arterial hypertension (52%), disorders of lipid metabolism (34%), obesity (25%), diabetes (20%) and arrhythmia (15%). After controlling for age and sex, the observed prevalence of the following ten chronic diseases was higher than expected: heart failure; chronic liver disease; asthma; generalised artherosclerosis; osteoporosis; ischaemic heart disease; thyroid disease; anxiety/depression; arrhythmia; and obesity. Conclusions: Patients with COPD, who are frequent in family practice, have a complex profile and pose a clinical and organisational challenge to FPs [ABSTRACT FROM AUTHOR]

Introduction: Healthcare management is oriented toward single diseases, yet multimorbidity is nevertheless the rule and there is a tendency for certain diseases to occur in clusters. This study sought to identify comorbidity patterns in patients with chronic diseases, by reference to number of comorbidities, age and sex, in a population receiving medical care from 129 general practitioners in Spain, in 2007. Methods: A cross-sectional study was conducted in a health-area setting of the Madrid Autonomous Region (Comunidad Autónoma), covering a population of 198,670 individuals aged over 14 years. Multiple correspondences were analyzed to identify the clustering patterns of the conditions targeted. Results: Forty-two percent (95% confidence interval [CI]: 41.8-42.2) of the registered population had at least one chronic condition. In all, 24.5% (95% CI: 24.3-24.6) of the population presented with multimorbidity. In the correspondence analysis, 98.3% of the total information was accounted for by three dimensions. The following four, age- and sex-related comorbidity patterns were identified: pattern B, showing a high comorbidity rate; pattern C, showing a low comorbidity rate; and two patterns, A and D, showing intermediate comorbidity rates. Conclusions: Four comorbidity patterns could be identified which grouped diseases as follows: one showing diseases with a high comorbidity burden; one showing diseases with a low comorbidity burden; and two showing diseases with an intermediate comorbidity burden. [ABSTRACT FROM AUTHOR]

Abstract: Smart meters (SM) may provide large benefits to all stakeholders by providing the information required to implement certain sets of demand response actions. Benefits produced by SM related actions depend on the features of these actions, the system and the targeted consumer group. We first lay out an analytical framework to analyze the application of Demand Response (DR) actions. Based on this framework, we describe a way to determine the response of domestic load in a system to the implementation of DR actions. We propose determining the overall change in the consumption behavior of domestic load based on previously obtained estimates of the peak load and overall consumption reduction for different types of consumers in different types of systems resulting from the application of each set of actions. We have carried out a comprehensive literature review to provide here such estimates. We apply the analytical framework and methodology developed to characterize the reaction of consumers in the Austrian system to different SM related actions. Finally, we provide guidelines on which DR actions to implement in this system and how to implement them. The use of advanced indirect feedback on consumption behavior, critical peak prices and simple time-of-use tariffs is advocated. [Copyright &y& Elsevier]

Background. Heart failure (HF) is a health problem that particularly affects the elderly population. Its onset is associated with other chronic diseases, a circumstance that makes it a challenge for health care services. The aim of this study is to quantify the prevalence of HF in family medicine offices and describe the chronic co-morbidity associated with it.Methods. A cross-sectional, observational descriptive study set in a health area of the Community of Madrid, Spain. The study was carried out in a population of 198 670 individuals over 14 years of age, attended to by 129 specialists in family medicine. The patient was considered to have HF when this diagnosis (ICPC code K77) appeared in his or her electronic medical record. The prevalence of HF was quantified and its association with another 25 chronic diseases was analysed.Results. The prevalence of HF was 6.9‰, 7.9‰ among women and 5.9‰ among men. Patients with HF had a high rate of chronic co-morbidity, with an average of 5.2 + 2.1 chronic diseases. Only 3% of the patients present with isolated HF and >60% have four or more additional chronic problems. Hypertension, cardiac arrhythmias, hyperlipidaemia, obesity and diabetes mellitus are the chronic diseases most frequently detected in HF patients.Conclusion. Patients with HF frequently visit the offices of family physicians, presenting with a high rate of cardiac and non-cardiac co-morbidity that proves to be a challenge on the clinical level and in terms of the organization of health care services. [ABSTRACT FROM PUBLISHER]

This work analyses the microstructure changes of various copper-based powder systems during sintering from 3D images provided by in situ synchrotron microtomography. The investigated systems include a copper powder with a wide particle size distribution of 0-63 µm poured into a quartz capillary, a pre-sintered copper compact with artificially created large pores and a mixture of copper and alumina particles. The experiments were carried out at the European Synchrotron in Grenoble, France. Powders were sintered up to 1060°C under reducing atmosphere in a furnace located between the X-ray source and the detector. During each experiment, 3D images were taken at various times of the thermal cycle. We have obtained images with a resolution of 1.5 µm and the time of acquisition of every image was ∼1 min. Quantitative analysis of these images allowed the changes of various important parameters to be followed. Such parameters characterise the sintering process at the particle length scale: interparticle coordination, pore size distribution and particle centre-to-centre distance. Moreover, by tracking the displacement of each particle centre and comparing it to the displacement predicted by classical mean field assumption, we have been able to assess the magnitude of particle rearrangement occurring during sintering. From these data, the sintering behaviour of heterogeneous powder systems is discussed with particular emphasis of collective particle phenomena. [ABSTRACT FROM AUTHOR]

Collective particle behavior such as interparticle coordination and particle rearrangement plays a significant role in the sintering of heterogeneous powder systems. Those phenomena have been investigated by in situ X-ray microtomography and discrete element simulation (DEM). In situ 3D images of sintering copper-based systems have been obtained at the European Synchrotron Research Facilities. The sintered systems comprise a dense packing of atomized copper powder with a size range of 0–63 μm and the same powder including artificial pores. Quantitative analysis of these images provided valuable data on local strain, coordination number, and particle movement. The sintering of the same systems has been simulated with the discrete element code dp3D. From this set of information, the importance of collective behavior on densification and microstructural evolution is assessed and the relevance of DEM to describe it is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Powder metallurgy allows composite materials, notably metal–ceramic composites, to be produced by sintering a mixture of powders. This work analyses the sintering behaviour of metal powder mixed with ceramic inclusions. Experiments have been performed with mixtures of copper and alumina particles of about the same size and volume fractions of alumina between 5 and 30%. The densification kinetics of powder mixtures have been deduced from dilatometry measurement and the microstructure of sintered materials has been observed by scanning electron microscopy. The sintering process has also been modelled by using discrete element method. From both experimental and simulation results the effect of inert inclusions on the densification of metal-ceramic powder mixtures during free sintering is discussed. We found in particular that the densification was significantly delayed even for a volume fraction of inclusions as low as 5% and strongly hindered when this content got to 20%. [Copyright &y& Elsevier]

Abstract: Calbindin cells represent a major interneuron subtype of the cortical/pallial regions, such as the basolateral amygdala, which are often analyzed in studies of tangential migration of interneurons from the subpallial ganglionic eminences to the pallium/cortex. However, previous evidence suggests that during development the calbindin cells may include more than one of the interneuron subtypes found in the adult pallium/cortex. Furthermore, in the adult basolateral amygdala, calbindin cells include a subpopulation of non-GABAergic (non-interneuron) cells. To better characterize these cells throughout development, in the present study we investigated the colocalization of calbindin, parvalbumin and GABA in cells of the mouse basolateral amygdala during late embryonic (E16.5) and several postnatal ages from birth until 4 weeks after birth (P0, P10 and P28). Our results indicate that CB, PV and GABA show a dynamic pattern of colocalization in cells of the mouse basolateral amygdalar nucleus throughout development. From E16.5 through P28, the majority of CB+ neurons and virtually all PV+ neurons are GABAergic. However, after P10, the percentage of GABAergic CB+ cells decline from 96% to 70%. Furthermore, while only 9% of CB+ neurons are PV+ at P10, this percentage raises to 42% at P28. At all postnatal ages studied, the majority of the PV+ cells are CB+, suggesting that PV+ interneurons develop postnatally mainly as a subpopulation within the CB+ cells of the basolateral amygdalar nucleus. These results are important for interpreting data from interneuron migration. [Copyright &y& Elsevier]

Parties to the Internal Electricity Market of the European Union (IEM) decided in 2001 to abolish the method of pan-caking of transmission tariffs for cross-border transactions that was originally in place. Instead, they have agreed to implement a system whereby national transmission tariffs provide access to the entire IEM. This system is supplemented by a scheme of inter-TSO payments. However, conflict may arise if the compensation that a country must pay another one is not in accordance with the electrical usage that the former is making of the grid of the latter. For instance, Inter TSO Compensation methods (ITC methods) implicitly allocate the cost of any existing or new transmission line. Therefore, the adoption of an inefficient method may be an obstacle for building some needed regional grid investments. Consequently, one should give careful consideration to the selection of the ITC method. This paper analyzes, both qualitatively and quantitatively, the implementation of the most relevant ITC methods that have been considered so far in the European debate. When assessing each method from a conceptual point of view, considerable attention is devoted to the critical examination of its main underlying assumptions. [ABSTRACT FROM AUTHOR]

Electricity transmission contracts allocate scarce resources, allow hedging against locational price differences, and provide information to guide investment. However, ownership of transmission contracts might enhance market power of strategic generators. If the allocation mechanism for transmission contracts does not prevent generators from obtaining market power-enhancing contracts, explicit restrictions on owning transmission contracts might be required. To ensure that these restrictions do not interfere with the need to hedge for transmission price risk, one proposal is to define all transmission contracts to a balancing point at which energy is traded. Generators are only allowed to own transmission contracts toward this balancing point. Traders or load hedge the price risk from this balancing point to the location of load with transmission contracts. We propose an algorithm and apply it to the European electricity network to identify a balancing point that reduces market power of generation companies and is well connected. Market-level data or detailed information about demand are not required. The only critical input is assumptions on future transmission constraint patterns. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a scheme for the management of network congestion in the Internal Electricity Market (IEM) of the European Union. This scheme tries to combine the rigor in the treatment of the energy and transmission capacity transactions with the flexibility and pragmatism that are necessary to make the scheme compatible with the current diversity of regulatory approaches and market structures in the Member States participating in the IEM. First, a reference scheme is presented with a complete formulation that jointly deals with the energy and capacity markets. Because of the implementation difficulties of this conceptually ideal approach, a more pragmatic scheme is proposed instead. The core of this scheme is an explicit auction mechanism that must be run prior to any short-term (daily, typically) energy markets. In this auction, where only transmission capacity is traded, both bilateral contracts and energy bids to Power Exchanges can participate in order to acquire the capacity that is necessary to carry out their transactions. Some technical issues related to the practical implementation of the proposed approach are also examined; these include market liquidity, the financial or physical nature of the long-term contracts, the potential problems of “slicing” transmission capacity and the allocation of congestion rents. Market power issues are ignored. [Copyright &y& Elsevier]

This paper investigates the application of adaptive control to the Spanish load-frequency regulation scheme, Automatic Generation Control (AGC). The Spanish AGC system regulates the frequency and the power exchange between France and Spain. The system is hierarchically structured with one master regulator that coordinates four control areas. Each control area is composed of several generating units providing AGC service. Co-ordinating signals are sent to the control areas so that the global system response achieves the objective established by the System Operator. The participation of each control area in the service is set according to the rated share that it has obtained in the secondary-reserve market and its relative response speed compared to that of the rest of the control areas. Some problems, such as the lack of sensitivity to the quality of the reserve provided by the control areas, have been detected in the operation of the current AGC scheme. A new design, which is presented in this paper, has been developed in order to overcome these problems. This paper attempts to outline how this new design improves the global AGC system response and the distribution of the regulation effort among the control areas. The proposed strategy is compared with the present design by means of simulation. [ABSTRACT FROM AUTHOR]

The present work is focused on developing Ti-xTa porous alloys processed by the space holder method and solid-state sintering. The volume fraction of Ta ranged between 20 and 30 wt.%. The sintering kinetics was evaluated by dilatometry tests. Sintered materials were characterized by SEM, XRD and computed tomography. Porosity features and permeability were determined from 3D images, and their mechanical properties were evaluated from microhardness and compression tests. The sintering behavior and the final microstructure are driven by the Ta diffusion into the Ti, slowing down the densification and modifying the transition temperature of α-to-β. Due to β-stabilization, martensite α′ was obtained after sintering. Mechanical properties are reduced because of the β-stabilization and pore addition, being predominantly the pore effect. Permeability depended on the pore characteristics, finding values close to the human bones. It was concluded that powder metallurgy generates highly TixTa alloys with a combination of α, β and α′ Ti phases as well as remaining Ta particles that are beneficial to improve the biocompatibility and osseointegration of such materials. Being the Ti25Ta40salt alloy the most suitable for orthopedic implants because of its characteristics and properties. [ABSTRACT FROM AUTHOR]

Study of the histiocytes from a large variety of skin diseases demonstrates a close relationship between the cell processes peculiar to those cells and their degree of phagocytic activity. The membrane structures, as well as the dense bodies localized in the peripheral cytoplasm, suggest a type of endocytosis distinct from pinocytosis and phagocytosis. [ABSTRACT FROM AUTHOR]

As a typical example of constrained sintering, the behavior of a complex ceramic powder system with multi-heterogeneities has been investigated. This powder system comprises inherent imperfections as well as rigid inclusions that act as constraints to densification. The sintering process of the system was monitored by in-situ X-ray nano-tomography at the European Synchrotron Radiation Facility (ESRF). This technique enables three-dimensional (3D) imaging of the microstructure with a voxel size of 25 nm. The images obtained reveal the distribution of imperfections in the powder system, such as particle aggregation and pore segregation in and around them. The subsequent in-situ evaluations show the evolution of the microstructure in the presence of inclusions. The study addresses the questions pertaining to the effect of the added constraints, the consequent crack generation and their implication on the final densification of the material. [Display omitted] [ABSTRACT FROM AUTHOR]

• Planning bike trips with novel data sources. • Using percolation theory to optimize cost and maximize global connectivity. • Network Science for detecting affinity of trips by income level and further inform local interventions. Cities around the world are turning to non-motorized transport alternatives to help solve congestion and pollution issues. This paradigm shift demands on new infrastructure that serves and boosts local cycling rates. This creates the need for novel data sources, tools, and methods that allow us to identify and prioritize locations where to intervene via properly planned cycling infrastructure. Here, we define potential demand as the total trips of the population that could be supported by bicycle paths. To that end, we use information from a phone-based travel demand and the trip distance distribution from bike apps. Next, we use percolation theory to prioritize paths with high potential demand that benefit overall connectivity if a bike path would be added. We use Bogotá as a case study to demonstrate our methods. The result is a data science framework that informs interventions and improvements to an urban cycling infrastructure. [ABSTRACT FROM AUTHOR]

Developing a regional power system to achieve a high level of integration of national systems requires sufficient development of the regional transmission grid. This is possible only with appropriate schemes for the complete cost–benefit analyses, and cost allocation of these transmission investments, which plays a critical role in the selection of the most efficient network investment and the proper assignment of their cost to the national systems. Network reinforcements affect the operation of power systems and, therefore, the externalities of power generation. This paper examines the impacts of integrating local air pollution damage from power production within the benefit assessment and cost allocation of transmission investments. The paper describes the methodology followed and illustrates its application in a real-life case study where a simplified version of a European network is considered. Within this case study, we have assessed the impact of considering the reduction in air pollution damage achieved through a particular HVDC project between France and Spain on the benefits, and benefit-driven cost allocation, computed for this project. In this case study, local pollution related benefits are a relevant fraction of the overall benefits of the considered transmission project. However, considering the local air pollution benefits of the project does not affect the net positive benefits of each country significantly, resulting in a limited change in the cost allocation of the project. [ABSTRACT FROM AUTHOR]

The effect of the oxidized functional groups on the structural, electronic, and reactivity properties of armchair graphene nanoribbons has been investigated in the framework of the density functional theory. The presence of functional groups near the edges stabilizes the oxidized graphene nanoribbons (OGNRs) more than substituting near the center. Overall, we found slight differences in the electronic properties of OGNRs concerning the pristine ones. The oxygen contribution of functional groups to the DOS is found in the conducting energy bands far from the Fermi level. Consequently, the semiconducting behavior is maintained after doping. Based on the reactivity of OGNRs, the most promising nanostructures were proposed as adsorbents studying the interaction and complexation with phenol, a critical pollutant removed mainly by hydrotreating processes (HDO) to produce bio-oil. Parallel and perpendicular phenol conformations were found towards the OGNRs in the optimized complexes driven by a physisorption process. These results provide significant insights for catalytic processes that use biomass derivatives containing phenolic compounds. The physisorption of streams containing pollutants on OGNRs could be adapted to new technological applications for the remotion of aromatic compounds under environmentally friendly operational conditions. [ABSTRACT FROM AUTHOR]

This work reports on the fabrication of a novel two-layer material composed of a porous tantalum core and a dense Ti6Al4V (Ti64) shell by powder metallurgy. The porous core was obtained by mixing Ta particles and salt space-holders to create large pores, the green compact was obtained by pressing. The sintering behavior of the two-layer sample was studied by dilatometry. The interface bonding between the Ti64 and Ta layers was analyzed by SEM, and the pore characteristics were analyzed by computed microtomography. Images showed that two distinct layers were obtained with a bonding achieved by the solid-state diffusion of Ta particles into Ti64 during sintering. The formation of β-Ti and α′ martensitic phases confirmed the diffusion of Ta. The pore size distribution was in the size range of 80 to 500 µm, and a permeability value of 6 × 10−10 m2 was close to the trabecular bones one. The mechanical properties of the component were dominated mainly by the porous layer, and Young's modulus of 16 GPa was in the range of bones. Additionally, the density of this material (6 g/cm3) was much lower than the one of pure Ta, which helps to reduce the weight for the desired applications. These results indicate that structurally hybridized materials, also known as composites, with specific property profiles can improve the response to osseointegration for bone implant applications. [ABSTRACT FROM AUTHOR]

The failure strength of annealed float glass is difficult to predict accurately due to several factors that influence the glass’ mechanical behavior, including stress rate, environmental conditions, fabrication process, glass thickness and the presence of surface flaws. Some of these parameters strongly depend on the construction practices of each country. This study aimed to assess the failure strength of annealed glass commonly used in the construction industry in Mexico, based on experimental tests. It is also determined experimental data dispersion as function of the glass thickness. The approach employs destructive tests on annealed glass plates subjected to out-of-plane loading in a coaxial double ring (CDR) test setup and analytical linear and a geometric non-linear finite element analyses. The mechanical behavior determined by the numerical model agrees with the failure strength and deflection obtained experimentally. The results show the mean failure strength of glass specimens with several thicknesses typically used in Mexico, and the analysis of data dispersion is also presented. The statistical analyses of glass failure strengths with thickness range 3–19 mm indicate that all samples cannot be considered coming from the same population and data dispersion depended on glass thickness. Finally, the use of the experimental results for evaluating mean failure strength of glass panels and a comparison with expected wind-induced pressure in buildings located in two sites in Mexico is exposed. [ABSTRACT FROM AUTHOR]

Background context The most common adverse event after a lumbar puncture (LP) is a headache: In anaesthesiology, well studied is the protective effect of atraumatic spinal needles, and they are routinely used. However, this is less well known in diagnostic LP, and neurologists use atraumatic needles in less than 2% of times. Purpose The purpose of this study was to define the impact of needle type, atraumatic (Sprotte [S]) versus traumatic (Quincke [Q]) on postdural puncture headache (PDPH) incidence. Study design The study is based on a prospective, randomized, and simple-blinded clinical trial. Patient Sample Patients older than 14 years were scheduled for a diagnostic or therapeutic LP. Outcome Measures The outcome measure included the development of PDPH according to the International Headache Association criteria. Methods Patients fulfilling eligibility criteria were randomly allocated to one of two kinds of spinal needle: atraumatic or S-type or traumatic or Q-type. They were interviewed on days 2 and 7 about the development of PDPH. Results The incidence of PDPH was 22.43% with Q-type needle and 8.51% with S-type needle, p=.04. The duration of PDPH in patients in the S-type was 1 day or less, compared with a median of 4.14 days in the Q-type (p=.00). In the logistic regression model, the S-type needle together with the age of the patient were the only two statistically significant factors in the development of postlumbar puncture headache (PLPH), both of them being protective. Conclusions We found a lower incidence of PDPH with atraumatic needles, and it was statistically significant compared with the traumatic needles. Our study confirms the effectiveness of the atraumatic needles to prevent PDPH. [ABSTRACT FROM AUTHOR]

• Visual mapping for classifying the linking approaches available in the literature with Energy System Models. • Formal methodology that provides a structured approach to address research questions in energy planning projects. • The proposal structured modeling methodology offers a comprehensive, research-question-oriented classification of models. • Short steps to address research questions, select models, and design their interaction and convergence procedures. Long-term energy planning increasingly relies on mathematical models offering quantitative insight to support complex policy decisions. However, the increase in their use has meant the proliferation of tools developed at different institutions, with various scopes, dealing with specific aspects of the economy, the power sector, or the climate, with mismatches in temporal or geographic resolution. All this creates a need for using several models concurrently, integrating them to generate a complete perspective on the implications of policy decisions on the energy transition. This article proposes a methodology to categorize and combine energy models and develop a manipulation strategy to answer a target research question. Thus, it gives a formal structure to tasks carried out informally −and suboptimally- in virtually any energy planning project. This methodology is based on structured modeling, a formal mathematical theory conceived for representing and manipulating models. It assumes a soft-linking approach, meaning the models share information without integrating them within the same platform or code. This framework was developed within the European project openENTRANCE, which will develop, use, and disseminate an open, transparent, and integrated modeling platform for assessing low-carbon transition pathways in Europe. [ABSTRACT FROM AUTHOR]

Emerging flexibility markets are increasingly characterised by many product characteristics, differing flexibility buyers, and a disparate set of potential Flexibility Service Providers (FSPs), including those connected to the distribution networks. The FSPs that do not have an individual schedule from previous markets (e.g., wholesale energy markets) need a counterfactual to verify service provision, often called the baseline. This paper investigates the fitness of various baseline methodologies while considering different resource, market, and product characteristics. A novel baseline decision framework is proposed. The analysis showcases that no one-size-fits-all baseline method exists while proposing alternatives for FSP types and flexibility market conditions. • Analysis of baseline methods in face of current and future flexibility market. • Development of a framework for baseline assessment. • Decision framework for baseline choice given the flexibility trading characteristics. [ABSTRACT FROM AUTHOR]

Growing load factors in winter and summer peaks are a serious problem faced by the Spanish electric energy system. This has led to the extensive use of peak load plants and thus to higher costs for the whole system. Wind energy represents a strongly increasing percentage of overall electricity production, but wind normally does not follow the typical demand profile. As generation flexibility is limited due to technical restrictions, and in absence of large energy storages, the other side of the equilibrium generation-demand has to react. Demand side management measures intend to adapt the demand profile to the situation in the system. [ABSTRACT FROM PUBLISHER]

We use discrete element method (DEM) simulations to study the evolution of defects during sintering. In DEM, the particulate nature of the sintering powder is taken explicitly into account because each particle is modeled as a discrete entity interacting with its neighbors. This allows to treat naturally the gain or the loss of contacts between particles, and to explicitly take particle rearrangement into account. These effects are particularly important when looking for the nucleation, growth or healing of local heterogeneities such as defects. We first study the evolution of a crack (generated, e.g., during ejection or drying processes) when no geometrical constraint is imposed. We then investigate how constrained sintering between two parallel planes may lead to crack initiation and growth. We show that the extent of interparticle rearrangement plays a major role in the evolution of the crack under such conditions. The main conclusion of these simulations is that some geometrical constraint is necessary for a defect to grow into a crack and that the presence of an initial defect is not a necessary condition to initiate cracks. [ABSTRACT FROM AUTHOR]

The aim of this validation study was to assess the measurement properties of the CECA (Spanish acronym for the Specific Questionnaire for Condylomata Acuminata) in patients with anogenital condylomas. A total of 247 patients aged >18 years completed the questionnaire on 2 occasions as well as the Dermatology Life Quality Index (DLQI). The CECA questionnaire showed good internal consistency (Cronbach's a values of 0.86 and 0.91 in the emotional and sexual activity dimensions) and good test- retest reliability (intraclass correlation coefficient 0.76 emotional dimension, 0.82 sexual activity dimension). Patients with de novo lesions and those with more extensive lesions and larger number of warts showed poorer health-related quality of life. CECA and DLQI scores correlated moderately. Patients whose lesions cleared at follow-up or with a reduction of ≥50% showed a better improvement of health-related quality of life. The CECA questionnaire is a valid, reliable and sensitive tool for the assessment of health-related quality of life in patients with anogenital warts. [ABSTRACT FROM AUTHOR]

Performing optimal transmission expansion planning (TEP) in real, large‐scale power systems such as the European one can be an unmanageable task, especially when long‐term time scopes and multiple scenarios are considered. Project e‐Highway had the daunting objective of planning the European network for the very long term and under high renewable energy penetration. The project objectives included the development of a planning methodology capable of applying optimisation to large‐scale systems that are currently unmanageable in practice. This study presents this approach, which is based on simplifying the system while keeping its main features and investment drivers. The simplified system is then expanded optimally for the full time scope. Last, the original system is expanded optimally for the first time horizon taking into account the constraints imposed by the full time‐scope optimisation of the simplified system. It illustrates the applicability of the method with a case study based on the European Union. [ABSTRACT FROM AUTHOR]