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The Global Activity Limitation Indicator (GALI) is an instrument that measures long-term overall disability. The objective of this study was to evaluate GALI's predictive value on mortality while examining variations according to sex, age, and educational level. Longitudinal study. This longitudinal study was based on 42,991 individuals aged ≥15 years who participated in the 2011–2012 National Health Survey and the 2014 European Health Survey in Spain. These records were linked to mortality data up to December 2021. GALI assessed self-reported functional limitation in the past 6 months and classified individuals into three categories: severely limited, limited but not severely, and not limited. Incidence rate ratios (IRR) were calculated using Poisson regression models, adjusting for sociodemographic, lifestyle, and health status variables. Compared to individuals with no limitations, those with non-severe limitations had an IRR for mortality of 1.27 (95% CI: 1.16–1.38), and 2.04 (95% CI: 1.81–2.31) in those with severe limitations. Women with severe limitations exhibited a higher IRR (2.32; 95% CI: 1.98–2.71) compared to men (1.73; 95% CI: 1.45–2.08) (P for interaction = 0.005). Individuals <65 years with severe limitations showed a greater association (2.22; 95% CI: 1.58–3.10) than those ≥65 (1.49; 95% CI: 1.32–1.69) (P for interaction <0.001). Among individuals with lower educational attainment, the IRR was 2.08 (95% CI: 1.83–2.37), and 1.87 (95% CI: 1.37–2.56) for the higher education group (P for interaction = 0.017). GALI is a robust predictor of all-cause mortality in the general population and subgroups. The association is stronger in women, individuals <65 years, and those with lower educational levels. [ABSTRACT FROM AUTHOR]

2018, 29: 1281 65 Kubota, K. Ito, H. Trends Chem. 2020, 2: 1066 66 Leitch, J A. Browne, D L. Chem. Eur. J. 2021, 27: 9721 67 Leonardi, M. Villacampa, M. Menéndez, J C. Chem. Sci. 2018, 9: 2042 68 Boldyreva, E. Faraday Discuss. Keywords: green chemistry; mechanochemistry; solid-state synthesis; synthetic organic chemistry; mechanoenzymology; sustainable chemistry; ball milling EN green chemistry mechanochemistry solid-state synthesis synthetic organic chemistry mechanoenzymology sustainable chemistry ball milling 2439 2459 21 07/31/23 20230817 NES 230817 Graph 1 Introduction Mechanochemistry, that is chemical transformations initiated or sustained by mechanical grinding or milling, or alternatively by twin-screw extrusion (TSE), with no or minimal solvent usage, has expanded from a laboratory curiosity to a useful, rapidly developing strategy for the preparation of molecules and amplification of their chemical reactivity. Chem. 2017, 13: 1907 20 Grätz, S. Borchardt, L. RSC Adv. 2016, 6: 64799 21 Willis-Fox, N. Rognin, E. Aljohani, T A. Daly, R. Chem. 2018, 4: 2499 22 Muñoz-Batista, M J. Rodriguez-Padron, D. Puente-Santiago, A R. Luque, R. ACS Sustainable Chem. Eng. 2018, 6: 9530 23 Dabral, S. Wotruba, H. Hernández, J G. Bolm, C. ACS Sustainable Chem. Eng. 2018, 6: 3242 24 Tan, D. Loots, L. Frisci'c, T. Chem. Commun. Xu, D.-Q. Green Chem. 2012, 14: 893 177 Jörres, M. Mersmann, S. Raabe, G. Bolm, C. Green Chem. 2013, 15: 612 178 Kristofíková, D. Meciarová, M. Rakovsky, E. Sebesta, R. ACS Sustainable Chem. Eng. 2020, 8: 14417 179 Némethová, V. Kristofíková, D. Meciarová, M. Sebesta, R. Chem. Rec. 2023, 23: e202200283 180 Mack, J. Shumba, M. Green Chem. 2007, 9: 328 181 Williams, M T. J. Morrill, L C. Browne, D L. ACS Sustainable Chem. Eng. 2020, 8: 17876 182 Veverková, E. Modrocká, V. Sebesta, R. Eur. J. Org. [Extracted from the article]

The least action principle played a central role in the development of modern physics. A major drawback of the principle is that its applicability is limited to holonomic constraints. In the present work, we investigate the energy lost by particles as a result of the gravitational interaction in a homogeneous low-density medium subject to non-holonomic constraints. We perform the calculation for an arbitrary particle and outline the specific result for photons. The energy lost is calculated from first principles based on the principle of virtual work and the d'Alembert principle. Under the formalism mentioned above, the dissipative nature of the effect is established. Furthermore, we show that the results agree with an alternative derivation based on continuum mechanics and the Euler–Cauchy stress principle. [ABSTRACT FROM AUTHOR]

The mining industry is currently undergoing a significant evolution in its production processes to search for greater sustainability in its operations. Historically, identifying the low performance of equipment occurs with inspections on the mining faces or through management reports. However, through the advent of technology and greater processing and data transmission capacity, many companies have developed research to improve the decision-making process to identify events in real-time to increase mine safety and act on low-performance equipment. Thus, this paper presents the development of a cyber-physical system to control loading productivity for open-pit mines. Furthermore, the tool allows analysis of the productivity, which generates alarms in low-performance situations measured according to pre-established targets. In the practical applications of the method, the increase in loading productivity reached 4.71% by reducing process variability. In addition, the stability of the loading operation resulted in the lowest queues, fuel consumption and greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Electricity storage is becoming one of the main challenges for the massive deployment of renewables. Thermal energy storage is gaining momentum, with molten salts-based systems being the state-of-the-art technology. As an alternative, Thermochemical Energy Storage (TCES) is a promising system that can increase the system performance in terms of energy storage density, maximum heat discharge temperature and long-term storage capacity. This work proposes and preliminary evaluates the performance of a novel modular Thermochemical Energy Storage (TCES) system based on the Calcium-Looping (CaL) process. The modularity allows its integration with multiple renewable energy sources into different high-temperature applications, including hard-to-decarbonise applications. Heat for the charging stage is provided by electrical heaters connected either to a Photovoltaic (PV) facility or directly to the grid. Limestone particles are heated, and once they reach their decomposition temperature (∼ 930 °C at 1 bar), the released CO 2 is removed from the reactor, cooled, compressed, and stored. When the stored energy discharge is required, CO 2 is supplied to the reactor to produce calcium carbonate and release the stored heat (∼ 400–875 °C). In the proposed concept, the solids remain in the reactor, and CO 2 is added or removed depending on the stage. As cases of study of the concept, energy storage systems integrated with PV plants of 0.5 and 20 MW e and grid-based storage are considered. An hourly simulation throughout the year is performed. Results show an energy density above 1 GJ/m3, higher than current molten-salt-based systems. The levelized energy storage cost is below 100 €/MWh for the grid-based storage, highlighting its potential to contribute significantly to the global energy transition. • A novel modular thermochemical electricity storage system is proposed. • The levelized storage cost ranges from approximately 85–190 €/MWh. • All analysed cases exhibit a high energy storage density (∼ 1 GJ/m3). • The implementation of an energy arbitrage strategy proves to be cost-effective. [ABSTRACT FROM AUTHOR]

• A detailed techno-economic analysis of the production of sustainable methane is developed. • Green methane production costs range from 100.67 €/MWh to 201.64 €/MWh. • Costs of CO 2 capture from 58.72 €/ton CO 2 to 61.88 €/ton CO 2. • Coupling Partial Oxycombustion with Amine and Methanation result in 9 years of ROI. This study explores the design of new WtE plants for municipal solid waste management, emphasizing CO 2 capture and conversion into CH 4. Two scenarios are assessed: Waste-to-Gas and Partial OxyWaste-to-Gas, both employing standard 30 % MEA CO 2 absorption technology. WtG integrates waste combustion with external hydrogen purchase for CO 2 hydrogenation to methane. In contrast, Partial OxyWtG incorporates a PEM electrolyzer for oxygen production, enabling oxygen-enriched air for partial oxycombustion. This approach facilitates CO 2 hydrogenation to methane alongside amine regeneration, thus mitigating the energy penalty typically linked with conventional amine processes. When considering realistic PPA prices and methane sale values, Partial OxyWtG emerges as potentially more cost-effective than current WtE plants without CO 2 capture. The cost of methane produced is significantly lower in partial oxycombustion scenarios (201.64 €/MWh and 100–138 €/MWh), primarily due to reduced hydrogen costs, leveraging current PPA rates of 40 to 60 €/MWhe. Additionally, the cost of avoided carbon is computed at 58.72 and 61.88 €/ton CO 2 , respectively. Efficiency penalties decreased from 6.49 to 1.47 percentage points. A lifecycle analysis of the project underlines the significance of incorporating CO 2 capture and utilization in WtE plant design, achieving optimal investment return within 9 years. [ABSTRACT FROM AUTHOR]

This paper presents the design of a tuned mass damper (TMD) for vibration control of a simply supported metal beam. Considering the mechanical properties of commercial springs and magnetic dampers, and applying the finite element method, the feasibility of couple a TMD that allow to reduce vibrations in the beam was evaluated. This paper describes the beam mechanical properties, as well as the characteristics of the tuned mass damper. These results can be used in construction of dynamic models that promote the experimental study of structures. The equations proposed by Deng Hartog were used to identify adequate stiffness and damping. Finally, it was evaluated the performance of the TMD in vibration control under impact excitation conditions. With the implementation of this device, were obtained reductions of more than 90%. [ABSTRACT FROM AUTHOR]

Objectives: . In the last decade, concern regarding the preparedness of general surgery graduates to effectively manage thoracic trauma cases has been raised. However, due to limited availability and elevated costs, access to cardiopulmonary trauma simulation models is limited. This article describes our experience implementing a low-cost blended ex vivo tissue-based simulation model using animal by-products that incorporates pump perfusion and ventilation.Design: . Firstly, for validation purposes 8 junior residents, 8 recently graduated general surgeons, and 3 cardiothoracic surgery attendings from Pontificia Universidad Católica de Chile Clinical Hospital were recruited. Proficiency in performing a pulmonary tractotomy and a myocardial injury repair was assessed with global and specific rating scales. Secondly, to evaluate the effectiveness of the model as a learning tool, 16 general surgery residents from different programs across the country were recruited receiving intensive, personalized training on the models. Proficiency was measured before and after the training.Results: . For the validation phase, significant differences among groups according to the previous level of expertise were shown, and therefore construct validity was established. The results of the second phase showed a significant overall improvement in participant's performance.Conclusion: . Effective training and assessment for advanced surgical skills in cardiothoracic trauma can be achieved using a low-cost pulsatile simulation model. [ABSTRACT FROM AUTHOR]

The gravitational deflection of light in the strong field limit is an important test for alternative theories of gravity. However, solutions for the metric that allow for analytic computations are not always available. We implement a hybrid analytic-numerical approximation to determine the deflection angle in static, spherically symmetric spacetimes. We apply this to a set of numerical black hole solutions within the class of modified gravity theories known as degenerate higher order scalar–tensor theories (DHOST). Comparing our results to a more time consuming full numerical integration, we find that we can accurately describe the deflection angle for light rays passing at arbitrary distances from the photon sphere with a combination of two analytic-numerical approximations. Furthermore, we find a range of parameters where our DHOST black holes predict strong lensing effects whose size is comparable with the uncertainty in the properties of the supermassive black hole in M87 reported by the event horizon telescope, showing that strong lensing is a viable alternative to put constraints on these models of modified gravity. [ABSTRACT FROM AUTHOR]

In this paper, we give a physical explanation to the accelerated expansion of the universe, alleviating the tension between the discrepancy of Hubble constant measurements. By the EulerCauchy stress principle, we identify a controversy on the lack of consideration of the surface forces contemplated in the study of the expansion of the universe. We distinguish a new general relativistic effect that modifies the spacetime fabric by means of the energy conservation equation. The resulting dynamical equations from the proposed hypothesis are contrasted to several testable astrophysical predictions. This paper also explains why we have not found any particle or fluid responsible for dark energy and clarifies the Cosmological Coincidence Problem. These explanations are achieved without assuming the existence of exotic matter of unphysical meaning or having to modify Einstein's Field Equations. [ABSTRACT FROM AUTHOR]

Objective: The objective is to compare new bone formation in critical defects in healthy, diabetic, and osteoporotic rats filled with hydroxyapatite (HA) alone and HA combined with simvastatin (SV). Materials and methods: A total of 48 adult female Sprague-Dawley rats were randomized into three groups (n = 16 per group): Group, 1 healthy; Group 2, diabetics; and Group 3, osteoporotics. Streptozotocin was used to induce type 1 diabetes in Group 2, while bilateral ovariectomy was used to induce osteoporosis in Group 3. The central portion of the rat mandibular symphysis was used as a physiological critical bone defect. In each group, eight defects were filled with HA alone and eight with HA combined with SV. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). Results: In all groups (healthy, diabetics, and osteoporotics), the defects filled with HA + SV presented greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with bone defects treated with HA alone. Conclusions: Combined application of HA and SV improves bone regeneration in mandibular critical bone defects compared with application of HA alone in healthy, diabetic, and osteoporotic rats. Clinical relevance: This study might help to patients with osteoporosis or uncontrolled diabetes type 1, but future studies should be done. [ABSTRACT FROM AUTHOR]

This paper provides a review of negative carbon capture technologies. Based on these technologies, here it is proposed an innovative negative emissions power plant combining the generation and storage of energy from biomass, photovoltaic, and concentrated solar power, capturing and recovering CO 2 by producing H 2 or CH 4 as green energy carriers. The main features of the system are i) large-scale energy production system with negative CO 2 emissions; ii) 100% renewable system based on biomass and solar energy with the possibility of integrating other renewables; iii) synergistic integration of processes and systems; iv) recovery of O 2 generated by photovoltaic-driven electrolysis within the process of partial biomass oxycombustion and v) solar-driven limestone calcination. A detailed model of the entire plant is developed to evaluate the integration of the process. The model performance is assessed on an hourly basis throughout the whole year. The base case results show an energy consumption from 1 to 2.1 MJ/kg CO 2 to capture 60–77% of CO 2 emitted from the biomass plant and green methane production of more than 7500 tons/year. The negative emissions associated with the process are -612 kg CO 2 /MWh. It justifies the interest in the proposed negative emissions power plant. [Display omitted] • A synergetic integration of CO2 capture, energy storage and methane production is proposed. • A biomass power plant is considered, resulting in -612 kg CO2/MWh negative emissions. • Solar PV and CSP are integrated into the process to reduce the SPECCA to 1–2.1 kg CO2/MWh. • A large amount of solids storage is required to achieve 70–90% CO2 capture capacity. [ABSTRACT FROM AUTHOR]

• A detailed techno-economic analysis of the production of sustainable methane is developed. • Green methane production costs range from 73.9 €/MWh to 180.4 €/MWh. • Costs of CO 2 capture from 58.87 €/ton CO 2 to 73.84 €/ton CO 2. • Average SPECCA and efficiency penalty of about 3.5 MJ/kg CO 2 and 6 % points, respectively. The worldwide deployment of renewable energy is growing exponentially. However, its intermittency limits its impact on the yearly energy contribution to the grid. Thus, coal remains the largest source of electricity generation in the world. Developing negative emissions technologies, such as Bioenergy with Carbon Capture and Utilization (BECCU), is a promising pathway. This study focuses on integrating waste biomass oxycombustion and a power-to-methane system. A proton exchange membrane electrolysis driven by photovoltaic solar energy is considered to produce hydrogen and oxygen, which is used for oxy-waste combustion in a sub-critical steam power cycle. Depending on the operation strategy, a certain amount of additional O 2 would be required, produced by a cryogenic distillation air separation process. At the exit of the boiler, the almost pure CO 2 stream is further purified, compressed, and sent to the methanation reactor. A quasi-stationary model of the entire plant is developed to simulate different operation conditions and assess the integration efficiency. The results show an excellent integration of the whole plant, with a yearly average efficiency penalty associated with the CO 2 avoided of 6 % points. Since waste biomass is used as fuel, the system provides −610 kg CO 2 /MWh emissions compared to biomass plants without CO 2 capture. Results from a yearly detailed techno-economic analysis show an average levelized cost of electricity of 199.56 €/MWh and an average green methane production cost of around 110.12 €/MWh. These yearly results involve a CO 2 capture cost of about 65.66 €/ton CO 2 , which justify the potential interest in the proposed system for new and retrofitted biomass power plants. [ABSTRACT FROM AUTHOR]

In recent years, sustainable organocatalysis has become a relevant target in asymmetric organic synthesis. Among the most successful strategies to achieve "greener" organocatalyzed processes are (1) the elimination of solvent from reaction media, and (2) the use of alternative activation energies such as solvent-free mechanochemistry in high speed ball mills. In recent years we have stepped up efforts in the pursuit of organocatalysts and biocatalysts that allow reactions to take place in the absence of solvent and under mechanochemical activation. In this article we present the application of small dipeptides as chiral organocatalysts under solvent-free and high-speed ball milling conditions, with focus on the asymmetric aldol addition reaction. Finally, we report on recent results using supported enzymes for the resolution of racemic β-amino acids and amines, under mechanochemical conditions. [ABSTRACT FROM AUTHOR]

• Solar photovoltaics stored by using cheap and abundant materials. • The Calcium-Looping process is integrated as electricity stored system (40% efficiency) • Electric-to-electric performance of the whole system reaches 57%. • A notable cost reduction could be achieved as alternative to batteries. Solar photovoltaic plants are today a competitive alternative to power plants based on fossil fuels. Cost reduction in photovoltaics modules, scalability and ease of installation of these plants are enabling a rapid worldwide expansion of the technology. Nevertheless, dispatchability still remains as the major challenge to overcome due the intrinsic variability of solar energy. Most of the current solar photovoltaic facilities at large scale lack energy storage while those with storage systems rely on expensive batteries. Batteries are based on elements such as nickel, lithium or cadmium whose scarcity hinder their sustainability for storing energy in the large scale. This manuscript presents a novel concept to integrate thermochemical energy storage in photovoltaic plants. Furthermore, the concept is also directly adaptable to wind power plants to store surplus energy. The paper analyses the suitability of the Calcium-Looping process as thermochemical energy storage system in solar photovoltaics plants. The system works as follows: part of the power produced in the solar plant provides electricity to the grid while the rest is used to supply heat for calcination of calcium carbonate. After calcination, the products of the reaction – calcium oxide and carbon dioxide- are stored separately. When power production is required, the stored products are brought together in a carbonation reactor wherein the exothermic reaction releases energy for power production. The overall system is simulated to estimate the process behaviour and results show that storage efficiencies of ∼40% can be achieved. Moreover, an economic analysis is developed to compare the proposed system with batteries. Due to the low price of natural calcium oxide precursors, such as limestone, and the expected longer lifetime of equipment as compared to batteries, the Calcium-Looping process can be considered as a potential alternative for improving dispatchability in solar photovoltaic plants. [ABSTRACT FROM AUTHOR]

The work was carried out to know the yield response of sugarcane depending on the stock and nutrition in three long term experiments conducted from 1978 to 2007 in a typical red Ferralitic soil, for the study of nitrogen (N), phosphorus (P) and potassium (K) doses, in the province of Ciego de Ávila, Cuba. Each of the experiments had 23 harvests. In the three experiments, the plant cane stock did not increase the yield with N and K applications and there was only a positive effect of phosphoric fertilization in 40% of them. Also, the set consisting of plant cane, first and second sprouts responded to N and K in 15 and 23%, respectively, reaching 54% in the case of the study of P. On the contrary, from the third sprout and up the sixth, responses were found in 100%, 90% and 80% of the harvests made in the experiments of N, P and K, respectively, associated with the worsening of soil conditions, stock aging and difficulty of root system to reach nutrients. [ABSTRACT FROM AUTHOR]

This paper investigates the effect that texting with WhatsApp, one of the most common applications for instant messaging, exerts on driving performance. Because distracted driving also affects older drivers, who can have seriously compromised vision, we also analysed the associations between visual-function parameters and driving performance. A total of 75 drivers, experienced in sending WhatsApp messages (≥10WhatsApp messages/week), participated in this study and were divided into four age categories. Visual-function tests included contrast sensitivity with and without glare, retinal straylight and objective assessment of optical quality. Simulated driving performance was assessed under a baseline driving condition (without distraction) as well as a texting condition (WhatsApp messages) while driving. The participants used their own mobile phone. Lastly, objective results of driving performance were compared with subjective self-report data from the Driver Behaviour Questionnaire (DBQ). The analysis indicated that functional changes occurring with age, such as a lower contrast sensitivity and greater retinal straylight, were correlated with a higher number of collisions, longer distances driven outside the lane, and greater standard deviation of lateral position (SDLP). The results showed a significant main effect of age for the driving-performance parameters. Also, compared to the baseline, texting WhatsApp messages while driving worsens driving performance for all age groups, most notably among older participants. Thus, the older drivers' SDLP was ∼14% higher than that for the baseline average of all the other drivers and rose to 29% under distraction, reflecting the impact of secondary tasks. The negative effect of the use of the smartphone during driving was also reflected in the number of collisions, with a greater risk of accidents in all the groups of drivers (by 8.3% for young adults, 25.0% for adults, 80.5% for middle-aged adults, and 134.5% for older drivers). Lastly, participants' subjective responses indicated that younger drivers (18–24 years) had a higher risk of deliberately violating safe driving practices (p < 0.05). The present study demonstrates that texting WhatsApp messages while driving significantly impairs the ability to drive safely, with older drivers being the group most adversely affected. It would be recommendable to include other nonstandard vision tests, which have shown associations with driving performance, in the examination for driver licensing. This would help raise the awareness of older drivers concerning their visual limitations, permitting them to adopt compensatory measures to improve their driving safety. Nevertheless, it is also necessary to raise awareness among the younger drivers of the risks involved in behaviour behind the wheel. [ABSTRACT FROM AUTHOR]

Analyzes the laser ablative hole formation in amorphous tellurium-selenium-iodine films. Information on laser ablative recording; Factors that cause the formation of a hole in thin films; Discussion on the preparation and properties of the films; Physical aspects of the laser ablative process; Description of the structure of the ablative holes in thin films.

Reports on the irradiation of gold (Au) islands on Al[sub2]O[sub3] with a pulsed laser beam. Details of the experiment; Distribution of arsenic-deposited Au islands; Effect of laser irradiation.

Integrating bioenergy and carbon capture and storage (BECCS) presents a great opportunity for power production with negative global CO 2 emissions. This work explores a novel synergetic system that integrates membranes, partial biomass oxycombustion and the calcium looping (CaL) process. Polymeric membranes generate oxygen-enriched air (OEA) with an O 2 concentration of 39%v/v, which is used for partial oxycombustion of biomass waste. The CO 2 -enriched flue gas evolves from the waste-to-energy plant to the CaL unit, where CO 2 concentration is increased up to 90–95%v/v, ready for purification and sequestration. Compared to only oxycombustion systems, the proposed concept presents fewer technological challenges in retrofitting boilers to waste-to-energy plants. Moreover, this new approach is highly efficient as integrating membranes to produce OEA instead of cryogenic distillation systems significantly reduces energy consumption. A novel integration concept is modelled to evaluate the whole process efficiency and the effect of key parameters on the system performance, such as the temperature of the reactors, the membrane surface area, and the partial oxy-combustion degree. The results show that the so-called mOxy-CaL system has an energy consumption associated with CO 2 capture below 4 MJ/kg CO 2 (a 31% lower than that for a conventional CaL process), with a higher CO 2 capture efficiency than oxycombustion and the CaL process separately. On the other hand, the economic analysis shows a higher CO 2 capture cost for the novel configuration than for the typical CaL configuration due to the additional investment cost of the membrane system. Improvements in membrane performance by increasing its permeance and diminishing the required surface area would significantly reduce the economic cost of this novel integration. Using membranes with permeance over 400 GPU would boost the system's competitiveness. • A synergetic CO 2 capture process combining oxycombustion and CaL is proposed. • The so-called mOxy-CaL system has an energy consumption below 4 MJ/kg CO 2. • Membranes permeance limits the profitability of the process. [ABSTRACT FROM AUTHOR]

The Calcium-Looping process is a promising thermochemical energy storage method based on the multicycle calcination-carbonation of CaCO 3 -CaO to be used in concentrated solar power plants. When solar energy is available, the CaCO 3 solids are calcined at high temperature to produce CaO and CO 2 , which are stored for subsequent utilization. When power is needed, these reaction by-products are fed into a carbonator reactor where energy is released from the exothermic carbonation reaction. In comparison with currently commercial energy storage systems, such as solar salts, the Calcium-Looping process presents several benefits such as the feasibility to work at significantly higher power cycle temperatures, a higher energy storage density and the possibility to store energy in the medium-long term. The present manuscript analyzes a number of novel Calcium-Looping configurations for energy storage combined with CO 2 cycles in a solar tower plant. The high overall efficiencies achieved (32–44%, defined as the ratio of net electric power production to net solar thermal power entering the calciner) indicate a potential interest for the integration of the Calcium-Looping process in Concentrating Solar Power Plants, although major technological challenges related to the design of the solar receiver and of the high temperature solids handling devices remain to be faced. [ABSTRACT FROM AUTHOR]

The main characteristics of the Public Health Sphere in Santiago de Cuba province are described, specifically those related to the following aspects: structure, associate specialists, net of relationships, activities carried out, current problems, as well as drawn up strategy at short and medium term, which will allow to give solution to the problems that can be presented. [ABSTRACT FROM AUTHOR]

Efficient, low-cost and environmentally friendly storage of thermal energy stands as a main challenge for large scale deployment of solar energy. This work explores the integration into concentrated solar power plants of the calcium looping process based upon the reversible carbonation/calcination of calcium oxide for thermochemical energy storage. An efficient concentrated solar power-calcium looping integration would allow storing energy in the long term by calcination of calcium carbonate thus overcoming the hurdle of variable power generation from solar. After calcination, the stored products of the reaction (calcium oxide and carbon dioxide) are brought together in a carbonator reactor whereby the high temperature exothermic reaction releases the stored energy for efficient power production when needed. This work analyses several power cycle configurations with the main goal of optimizing the performance of the overall system integration. Possible integration schemes are proposed in which power production is carried out directly (using a closed carbon dioxide Brayton power cycle) or indirectly (by means of a steam reheat Rankine cycle or a supercritical carbon dioxide Brayton cycle). The results obtained show that the highest plant efficiencies (up to 45–46%) are achievable using a closed carbon dioxide Brayton power cycle. [ABSTRACT FROM AUTHOR]

The application of six novel α,β-dipeptides as chiral organocatalysts in the asymmetric Michael addition reaction between enolizable aldehydes and N-arylmaleimides or nitroolefins is described. With N-arylmaleimides as substrates, the best results were achieved with dipeptide 2 as a catalyst in the presence of aq. NaOH. Whereas dipeptides 4 and 6 in conjunction with 4-dimethylaminopyridine (DMAP) and thiourea as a hydrogen bond donor proved to be highly efficient organocatalytic systems in the enantioselective reaction between isobutyraldehyde and various nitroolefins. [ABSTRACT FROM AUTHOR]

Partial oxycombustion using Oxygen-Enriched Air (OEA), produced by air-gas separation with polymeric membranes, combined synergistically with CO 2 capture technologies, can reduce the overall energy cost of CO 2 capture, and it is a potential alternative to conventional CO 2 capture technologies. An exhaustive review of polymeric membranes for this application is presented. The best membranes showed permeability values in the 450–25,100 barrer and selectivities higher than 3.6 for large-scale operations. These membranes can produce OEA with oxygen molar concentrations of up to 40% for retrofitting large-scale power plants (∼ 500 MWe) with partial oxycombustion. For OEA production, the polymeric membrane system is more efficient than cryogenic distillation since the specific power consumption of the former is 35.17 kWh/ton OEA. In comparison, that of the latter is 49.57 kWh/ton OEA. This work proposes that the OEA produced by the membranes feed a partial oxycombustion process integrated with calcium looping within a hybrid CO 2 capture system. The power consumption of the hybrid CO 2 capture system proposed here is 29.05% lower than in the case OEA is produced from cryogenic distillation, which justifies the potential interest in using polymeric membranes for OEA production. • Polymeric membranes for partial oxycombustion in CO 2 capture systems are evaluated. • Permeabilities of 500 to 25,100 barrer and selectivities from 2.7 to 5.1 are required in vacuum transmembrane pressures. • Polymeric membranes reduce by 29.05% the energy consumption (kWh/ton OEA). • A CO 2 capture system combining membranes, partial oxycombustion, and CaL is assessed. • SPECCA (MJ/kg CO 2) is reduced by 10.95% using membranes-based hybrid system. [ABSTRACT FROM AUTHOR]

This paper proposes a novel CO 2 capture technology from the integration of partial oxy-combustion and the Calcium-Looping capture process based on the multicycle carbonation/calcination of limestone derived CaO. The concentration of CO 2 in the carbonator reactor is increased by means of partial oxy-combustion, which enhances the multicycle CaO conversion according to thermogravimetric analysis results carried out in our work, thus improving the CO 2 capture efficiency. On the other hand, energy consumption for partial oxy-combustion is substantially reduced as compared to total oxy-combustion. All in all, process simulations indicate that the integration of both processes has potential advantages mainly regarding power plant flexibility whereas the overall energy penalty is not increased. Thus, the resulting energy consumption per kilogram of CO 2 avoided is kept smaller than 4 MJ/kg CO 2 , which remains below the typical values reported for total oxy-combustion and amine based CO 2 capture systems whereas CO 2 capture efficiency is enhanced in comparison with the Calcium-Looping process. [ABSTRACT FROM AUTHOR]

Heusler-type Ni-Mn-based metamagnetic shape memory alloys (MetaMSMAs) are promising candidates for magnetic refrigeration. To increase heat exchange rate and efficiency of cooling, the material should have a high surface/volume ratio. In this work, the typical Ni50Mn35In15 MetaMSMA was selected to fabricate thin ribbons by melt-spinning. The characteristic transformations of the ribbons were determined by calorimetry, X-ray diffraction, scanning electron microscopy and thermomagnetization measurements. The inverse and conventional magnetocaloric effects (MCEs) associated with the martensitic transformation (MT) and the ferromagnetic transition of the austenite (TCA), respectively, were measured directly by the adiabatic method (ΔTad) and indirectly by estimating the magnetic entropy change from magnetization measurements. It is found that the ribbons exhibit large values of ΔTad = 1.1K at μ0ΔH = 1.9 T, in the vicinity of the MT temperature of 300K for inverse MCE, and ΔTad = 2.3K for conventional MCE at TCA = 309 K. This result strongly motivates further development of different MetaMSMA refrigerants shaped as ribbons. [ABSTRACT FROM AUTHOR]

In areas of Southern Europe with very intensive pig production, most of the pig slurry (PS) is applied as fertilizer. However, in the European Union, no more than 170 kg N ha −1 year −1 can be applied in nitrate vulnerable zones (NVZs) from livestock manures. In this context, a six-year trial was conducted for a maize-triticale double-annual forage cropping rotation under rainfed conditions. Four different N rates were applied (0, 170, 250 and 330 kg N ha −1 year −1 ), to evaluate their effect on crop yield, N uptake, unrecovered N and soil nitrate content. The corresponding PS rates were defined as zero (PS 0), low (PSL) medium (PSM) and high (PSH). The annual average dry matter (DM) yields (maize + triticale) for the PS fertilization treatments PS0, PSL, PSM and PSH were 12.6, 17.7, 20.2 and 22.0 Mg DM ha −1 , respectively. Maize DM yield was influenced mainly by weather conditions, and triticale DM yield was clearly influenced by initial soil NO 3 − -N and PS fertilization rates. Unrecovered N was affected by PS fertilization rate and initial soil NO 3 − -N content. A residual effect of the PS when applied to maize had an important effect on soil NO 3 − -N and subsequent triticale DM yield. Moreover, total annual average unrecovered N, considering the sum of both crops (maize + triticale), were 91, 144, and 222 kg N ha −1 in PSL, PSM and PSH, respectively. In order to avoid part of this unrecovered N, mainly by lixiviation of nitrates, PS fertilization in triticale should be applied as side dressing at tillering. The application of N, in the form of PS, at rates higher than the legally permitted maximum of 170 kg N ha −1 year −1 , may result in better yields. However, high rates of PS fertilization may originate in significantly lower N use efficiency and a higher potential environmental impact in double-cropping systems, practiced in rainfed sub-humid Mediterranean conditions. [ABSTRACT FROM AUTHOR]

A non-destructive method based on external visible and near-infrared reflection spectroscopy for determining the internal quality of intact mango cv. ‘Osteen’ was investigated. An internal quality index, well correlated with the ripening index of the samples, was developed based on the combination of a biochemical property (total soluble solids) and physical properties (firmness and flesh colour) of mango samples. The diffuse reflectance spectra of the samples were recorded and used to predict the internal quality and the ripening index. These spectra were obtained using different spectroscopic external measurement sensors involving a spectrometer, capable of measuring in different spectral ranges (600–1100 nm and 900–1750 nm), and also a spectrocolorimeter that measured in the visible range (400–700 nm). Three regression models were developed by partial least squares to establish the relationship between spectra and indices. Good results in the prediction of internal quality of the samples were obtained using the full spectral range (R p 2 = 0.833–0.879, RMSEP = 0.403–0.507 and RPD = 2.341–2.826) and some selected wavelengths (R p 2 = 0.815–0.896, RMSEP = 0.403–0.537 and RPD = 2.060–2.905). The results obtained from this study revealed that external visible and near-infrared reflection spectroscopy can be used as a non-destructive method to determine the internal quality of mango cv. ‘Osteen’. [ABSTRACT FROM AUTHOR]

Oxyfuel combustion is a promising alternative to decarbonize the power sector. However, the main barrier to commercial deployment of the technology is the high energy consumption associated with oxygen production (∼200–300 kWh per ton of O 2), which penalizes the thermal-to-electric efficiency of 8.5–12% compared to traditional air combustion plants. Typically, oxygen is obtained from a cryogenic air separation process. However, other technologies have been gaining momentum in recent years, such as membrane technologies, chemical looping air separation, and renewable-driven electrolysis. The present work evaluates all these options for O 2 production to retrofit a 550 MWe coal-fired power plant with oxyfuel combustion. A techno-economic assessment is carried out to estimate the energy penalty, the O 2 production cost (€/ton) and the Levelized Cost of Electricity. The best results are obtained by combining oxygen transport membranes and electrolysis since the energy consumption has been reduced to 98.56 kWh/ton of O 2 , decreasing by 59.31% the cryogenic distillation energy consumption (242.24 kWh/ton O 2), reducing the overall energy penalty compared to cryogenic air separation from 8.88% points to 7.56%points. The oxygen transport membrane presents the lowest cost of electricity in retrofitting cases, 51.48 $/MWh, while cryogenic distillation estimated cost is 52.7 $/MWh. Their costs of avoided CO 2 are 31.79 $/ton CO 2 and 34.15 $/ton CO 2 respectively. • Assessment of different O2 production technologies to retrofit a 550 MWe power plant. • Membranes can decrease the specific energy consumption below 100 kWh/ton of O2. • Renewable-driven electrolysis is not enough to satisfy the oxygen demand at a large scale. • Significant reduction in energy penalty using membranes instead of cryogenic distillation. • The cost of CO2 avoided can be reduced below 35 $/ton. [ABSTRACT FROM AUTHOR]

The Calcium-Looping (CaL) process, based on the multicyclic calcination-carbonation of CaCO 3 /CaO, is considered a promising Thermochemical Energy Storage (TCES) technology to be integrated into Concentrating Solar Power (CSP) plants. This work proposes a novel CaL integration that operates at low-pressure calcination under pure CO 2 and a moderated temperature. Low-pressure calcination (0.01 bar) provides a suitable solution to mitigate CaO sintering and its consequent loss of reactivity in the carbonation stage. Since the temperature for quick calcination in a pure CO 2 atmosphere is decreased (from around 950 °C at 1 bar to 765 °C at 0.01 bar), the energy losses at the receiver are minimised. In addition, a reduced calcination temperature allows for the use of metallic receivers already tested at the MW-scale, which significantly increases the CSP-CaL integration reliability. Moreover, multicycle CaO reactivity is promoted in short residence times, allowing the use of a simpler reactor design. Furthermore, there is an increase of 85% in the energy storage density of the system. The proposed plant proposes a smooth integration of the CaL process in CSP plants, with a moderate storage level and supported by a natural gas backup system (solar share higher than 50%). The results show that the solar thermal-to electric efficiency is above 30%. [ABSTRACT FROM AUTHOR]

The Ca-Looping (CaL) process is at the root of a promising 2nd generation technology for post-combustion CO 2 capture at coal fired power plants. The process is based on the reversible and quick carbonation/calcination reaction of CaO/CaCO ​3 at high temperatures and allows using low cost, widely available and non toxic CaO precursors such as natural limestone. In this work, the efficiency penalty caused by the integration of the Ca-looping technology into a coal fired power plant is analyzed. The results of the simulations based on the proposed integration model show that efficiency penalty varies between 4% and 7% points, which yields lower energy costs than other more mature post-combustion CO 2 capture technologies such as the currently commercial amine scrubbing technology. A principal feature of the CaL process at CO 2 capture conditions is that it produces a large amount of energy and therefore an optimized integration of the systems energy flows is essential for the feasibility of the integration at the commercial level. As a main novel contribution, CO 2 capture efficiency is calculated in our work by considering the important role of the solid-state diffusion controlled carbonation phase, which becomes relevant when CaO regeneration is carried out under high CO 2 partial pressure as is the case with the CaL process for CO 2 capture. The results obtained based on the new model suggest that integration energy efficiency would be significantly improved as the solids residence time in the carbonator reactor is increased. [ABSTRACT FROM AUTHOR]

In this work, we present an alternative optical method to determine the probe-sample separation distance in a scanning near-field optical microscope. The experimental method is based in a Lloyd's mirror interferometer and offers a measurement precision deviation of ~100 nm using digital image processing and numerical analysis. The technique can also be strategically combined with the characterization of piezoelectric actuators and stability evaluation of the optical system. It also opens the possibility for the development of an automatic approximation control system valid for probe-sample distances from 5 to 500 μm. [ABSTRACT FROM AUTHOR]

Objectives Metabolic syndrome (MetS) is highly prevalent in patients with systemic lupus erythematosus (SLE) and it has been associated with increased cardiovascular risk. We examined the contribution of MetS to inflammatory markers, arterial stiffness and circulating endothelial progenitor cells (EPCs) as surrogates of subclinical atherosclerosis. Methods Cardiovascular risk factors, SLE-specific factors and peripheral blood EPCs were assessed in 50 female SLE patients. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III. Simultaneously, atherosclerosis was assessed by measuring the carotid–femoral pulse wave velocity (PWV) by doppler velocimetry. Results Beyond the factors included in the definition, SLE patients with MetS have a significantly higher serum level of uric acid (6.88 ± 2.20 vs 4.45 ± 1.17, p < 0.001) and some inflammatory biomarkers such as homocysteine, IL-8, sICAM-1 or complement molecules. The presence of MetS in our patients was closely linked with a significantly increased patient organ damage score (3.20 ± 1.97 vs 1.60 ± 1.67, p = 0.008), a decreased percentage of circulating EPCs (0.53 ± 0.24 vs 0.85 ± 0.57, p = 0.007) and an increased arterial stiffness (9.89 ± 2.40 vs 7.13 ± 1.51, p < 0.001). Conclusions MetS may contribute to the development of atherosclerosis by significantly increasing inflammation levels and arterial stiffness and decreasing circulating EPCs. This finding would justify close monitoring of these patients. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present and discuss some of the evidence regarding the resources that students use when they establish relationships between a contextual situation and an ordinary differential equation (ODE). We present research results obtained from work by seven students in a graduate level course in mathematics education, where they were involved in solving tasks based on the study of ODEs. The students’ mastery of digital tools allowed them to use and articulate different mathematical representations to comprehend how phenomena develop. The use of digital tools helped to enhance the students’ interpretation of the relationships between the context and the mathematical model associated with it. We also found that difficulties related to interpretation are grounded in the literal relationship that students make between their mental model of how a phenomenon develops and its mathematical representations. [ABSTRACT FROM PUBLISHER]

The Ca-Looping (CaL) process is considered as a promising technology for CO 2 post-combustion capture in power generation plants yielding a minor penalty on plant performance as compared with other capture technologies such as conventional amine-based capture systems. This manuscript presents a new carbonator reactor model based on lab-scale multicyclic CaO conversion results, which take into account realistic CaO regeneration conditions that necessarily involve calcination under high CO 2 partial pressure and high temperature. Under these conditions, CaO conversion in the diffusion controlled stage is a relevant contribution to the carbonation degree during typical residence times. The main novelty of the model proposed in the present work is the consideration of the capture efficiency in the diffusion controlled phase of carbonation. It is demonstrated that increasing the residence time by a few minutes in the carbonator yields a significant improvement of the capture efficiency. Model predictions are shown to agree with experimental results retrieved from pilot-scale tests. The new model allows a more accurate evaluation and prediction of carbonator’s performance over a wider range of residence times. The results obtained may be relevant for the optimization of CaL operation parameters to be used in real power plants. [ABSTRACT FROM AUTHOR]

As such, open acknowledgment of our field's past abuses by academic dermatology departments and professional organizations is vital for rectifying historically fractured trust in the medical establishment and for strengthening patient-provider relationships moving forward. Racial differences in perceptions of psoriasis therapies: implications for racial disparities in psoriasis treatment. Dear Editor, The world has witnessed a crucial resurgence of racial equity movements following the highly publicized deaths of George Floyd, Breonna Taylor and Ahmaud Arbery, among others. [Extracted from the article]

In dryland agricultural systems, pig slurry (PS) is usually applied to cereal crops only at sowing, and slurries accumulate for the rest of the year in pits. In this context, a four-year experiment was established in order to evaluate the feasibility of PS applications at the barley or wheat tillering stage. The main treatments were PS either applied at sowing (25 Mg ha −1 ) or not, but they alternated after a two-year period. Both were annually combined with eight side-dressing treatments at cereal tillering: mineral N as NH 4 NO 3 (M; 60 or 120 kg N ha −1 yr −1 ), PS from fattening pigs (PSf; 17, 30, 54 Mg ha −1 yr −1 ), PS from sows (PSs; 25, 45, 81 Mg ha −1 yr −1 ) and a treatment without N. The combined fertilization treatments were 18 plus a control (no N applied). In the context of crop rotation, the biennial alternation of PS applied at sowing allowed the control of soil nitrate increments, while PS side-dressing improved N recovery compared with a unique application at sowing. The highest yields (>3.6 Mg ha −1 yr −1 ) were obtained with an annual average (4-yr) N rate close to 173 kg N ha −1 (±40 kg N ha −1 ). The best overall strategies corresponded to PSs side-dressings of 50–90 kg N ha −1 . These PSs rates also recorded the highest values on the five calculated N-efficiency indexes, which were higher than or similar to results from M side-dressings or those recorded in the literature. These similarities (M vs. PSs) were also shown by the reduction of unaccounted-for N inside the overall N balance. Thus, split PS application during the crop cycle is a sound fertilization option in dryland systems. [ABSTRACT FROM AUTHOR]

Mechanical handling of fresh-market citrus is restricted by damage susceptibility. The objective of this research study was to determine the effect of variety and storage conditions on the resistance of citrus to impact damage. Three citrus varieties, two of them in two different stages of maturity, were tested in two different experiments: a freedropping experiment and a physical properties experiment. Two relative humidity conditions and two temperature conditions were studied. In the physical properties test, puncture resistance and compression resistance were measured. Significant differences were found in the damage resistance of each of the varieties. Puncture resistance of the peel of postharvest citrus and whole-fruit compression resistance are related to storage temperature and relative humidity conditions. To increase citrus whole-fruit compression resistance and peel puncture resistance, low temperatures and high relative humidity should be used. Under suitable previous temperature and relative humidity conditions, citrus varieties such as 'Valencia Late,' with a high resistance to compression and low peel deformation, could be apt for aggressive mechanical handling. [ABSTRACT FROM AUTHOR]

The Salar de Atacama is located in the most arid desert in the world. Despite its extreme conditions, it has many ecosystems of high ecological value. The Soncor ecosystem, a sequence of lagoons, is the most important environment of the region as it acts as the centre for the breeding of the Andean Flamingo. This salt flat also contains significant mining deposits and is an important water source for the region. Freshwater and brine—enriched in lithium and potassium—are being pumped from the aquifers near to the Soncor ecosystem, which has so far not been greatly affected by this groundwater extraction. However, there is a potential risk that future anthropogenic effects may disturb this fragile environment. The objective of this study is to determine the origin of the water sources of the Soncor ecosystem so as to adequately manage its water resources. Three hypotheses previously proposed in the technical literature were investigated in order to determine proactive actions to protect this fragile ecosystem. The study utilized classic hydrogeological techniques, such as the construction of stratigraphic profiles, piezometric maps and stream gauging, combined with less-common isotopic techniques, such as the87Sr/86Sr ratio. The results confirmed the hypothesis that the origins of the water sources are associated with groundwater inputs coming from the east side of the salt flat, in the north of the basin. EditorZ.W. Kundzewicz;Associate editorM. Acreman CitationOrtiz, C., Aravena, R., Briones, E., Suárez, F., Tore, C., and Muñoz, J.F., 2014. Sources of surface water for the Soncor ecosystem, Salar de Atacama basin, northern Chile.Hydrological Sciences Journal, 59 (2), 336–350. [ABSTRACT FROM PUBLISHER]

A descriptive and longitudinal study was conducted in 32039 patients under 5 years with acute respiratory infections, discharged from Southern Children Teaching Hospital of Santiago de Cuba, from January 1997 to December 2010, to characterize the morbidity from these infections in those affected. Among the analyzed variables were age, sex, types of acute respiratory infections, and epidemiological factors that predispose to morbidity or death due to pneumonia, microbiological studies and morbidity rates from acute respiratory infections. Upper airways infections, patients aged 2 months to 4 years and male sex prevailed as well as anemia, poor breastfeeding practices, previous use of antimicrobials and teenage mothers. Prevalence rates showed little annual variability during the decade consistent with gross morbidity. [ABSTRACT FROM AUTHOR]

Mechanical citrus harvesting systems in Spain can solve the problem of the high costs of manual harvesting. Previous results, without the use of abscission agents, have shown the effectiveness of trunk and limb shakers for mechanical citrus harvesting. It is crucial to define the adequate vibration time to achieve an acceptable removal percentage because a higher vibration time could render the operation economically unviable. To address mechanical citrus harvesting, it is also necessary to determine the vibration conditions (amplitude, frequency, and duration) to ensure maximum removal efficiency. The objective of this research is to determine the optimal combination of vibration frequency, amplitude, and duration that will ensure maximum removal efficiency in mechanical citrus harvesting. 'Marisol' and 'Orogrande ' mandarin trees were tested and harvested with a commercial trunk shaker. The 'Marisol" trees were shaken at a vibration of 15 Hz for 5 s with a 0.030 m displacement. The 'Orogrande' trees were shaken at 15 and 20 Hz frequencies with two shakes, the first lasting 5 s and the second lasting 2 s, 3 to 4 s after the first shake, with a 0.030 m displacement. Due to the low trunk height of orchard trees' in the Valencia region, it is impossible to study intermediate and high amplitudes with a commercial olive trunk shaker. To solve this limitation, a laboratory unidirectional vibratory device was used to shake the branches at a vibration frequency of 4.6 to 18.1 Hz and a vibration amplitude modified from 0.06 to 0.18 m. The field and laboratory results show that the mechanical citrus removal percentage exhibits a logarithmic behavior with time. The laboratory test shows that high-amplitude and intermediate vibration frequencies in the branches achieve adequate removal percentages. Lengthening the shaking time and repeating the shaking process do not increase the removal efficiency. In the field test, almost all the detached fruit fell in the first 2 to 3 s of shaking. It was evident that two shakes were not necessary to obtain an acceptable removal percentage. The results found in the laboratory indicate the possibility of reducing the frequencies and increasing the amplitudes to achieve an optimal mechanical citrus harvest. In the fresh market for citrus from the Mediterranean region, with very low citrus trunk heights, mechanical harvesting equipment can be adapted to achieve high vibration amplitude and intermediate vibration frequencies in the branches. [ABSTRACT FROM AUTHOR]

Abstract: A convenient synthetic procedure for the preparation of seven-membered cyclic α,β-dipeptides is described. Following coupling of N-protected α-amino acids with N-substituted β-amino acid tert-butyl esters, that affords linear α,β-dipeptides, the protecting groups at the terminal functionalities were removed and the open-chain dipeptides were cyclized with phenylphosphonic dichloride, PhP(O)Cl2, to give the desired cyclic α,β-dipeptides in good yields. NMR studies, X-ray diffraction analysis, and DFT calculations provided evidence for the conformation adopted by these cyclic dipeptides in solution, in the solid-state, and in the gas phase. [Copyright &y& Elsevier]

Purpose: Breast density is considered a significant risk factor and an important biomarker influencing the later risk of breast cancer. Prior breast segmentation is required when quantifying breast density with MRI in order to calculate the total breast volume and exclude nonbreast surrounding tissues. This paper describes an automatic 3D breast volume segmentation approach. Methods: The method is based on 3D local edge detection using phase congruency and Poisson surface reconstruction to extract the total breast volume. The boundary localization framework is integrated to a subsequent shape atlas-based segmentation using a Laplacian framework. Results: The 3D segmentation achieves breast-air and breast-chest wall boundary localization errors with a median of 1.36 mm and 2.68 mm, respectively, and an average volume error of 153.8 cm3 when tested on 409 MRI datasets. Furthermore, the breast volume assessment technique will produce a 5.3% variability in the estimation of breast density in the tested population. Conclusions: The fully automated segmentation approach of the breast in MRI allows the computation of total breast volume, a step required for breast density assessment. The use of features invariant to image intensity and a shape atlas to reinforce shape consistency are attractive characteristics of the method. Error analysis demonstrates that 5.3% variability in the estimation of breast density incurred by the method is an acceptable trade-off. [ABSTRACT FROM AUTHOR]

The propagation of gravitational waves offers new possibilities for testing the theory of gravity. Amongst these possibilities there is the luminosity distance of gravitational waves, d g w . A few phenomenological parametrizations for this property have been proposed in the literature, but their generality is still under study. In this work, we contribute to this study by confronting these parametrizations to the predictions of quadratic and degenerate higher order gravity. Furthermore, we propose a novel parametrization that unifies some of the existing proposals. We expect our findings to be relevant for future constraints on modified gravity based on the properties of standard sirens. [ABSTRACT FROM AUTHOR]