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This research examines the viability of rooftop photovoltaic systems for electricity self-consumption in Spain's residential sector, analyzing municipality-level data on electricity demand, rooftop availability, solar irradiance, and various electricity market and surplus policy scenarios. Differences are found between rural and urban contexts, with rural areas exhibiting greater potential for photovoltaic systems deployment due to more available rooftop space. The study highlights the crucial role of surplus electricity management, showing that an efficient use can significantly boost self-consumption potential, particularly in rural areas where surplus constitutes about two-thirds of the photovoltaic production. Economic analyses under different electricity market conditions and surplus compensation policies show that these factors critically affect the attractiveness and viability of these systems. Current high electricity prices in Spain have reduced their payback period, but the prevalent surplus compensation policy, a 1-month net billing feed-in tariff, reduces their cost-effectiveness by up to 60 % compared to a hypothetical 12-month net billing approach. The findings underscore the need for policy adjustments to maximize rooftop occupancy and ensure fair compensation of surpluses, highlighting the importance of tailored strategies for effective sustainable photovoltaic systems deployment in residential contexts. [ABSTRACT FROM AUTHOR]

In response to the European Commission's renewable energy targets for 2030, this study presents a comprehensive, data-driven evaluation of the potential for electricity self-consumption in the Spanish residential sector based on rooftop PV systems. Utilizing real-time hourly electricity demand data and various surplus compensation policies, the research highlights the significance of data granularity, indicating that annual data-based PV estimations can lead to rooftop PV self-consumption capacity overestimations when compared to hourly data assessments. Furthermore, geographical variations reveal distinct rooftop PV self-consumption capacities between urban and rural areas, driven mainly by the prevalent building typologies. This discrepancy suggests that while rural regions, with their predominance of single-family dwellings, offer higher PV generation potential due to more available rooftop space, urban areas, dominated by multi-story buildings, face significant constraints in rooftop surface availability. Economically, the current surplus compensation policy in Spain reduces the profitability of PV installations, underscoring the necessity for enhanced policies to fully utilize all the available rooftop areas in the residential sector. The study's findings, particularly the revelation that residential rooftops in Spain may not be enough to meet the current electricity demand, emphasize the need for adaptive, region-specific policies and the potential role of energy communities. Policymakers and industry stakeholders are urged to prioritize rooftop utilization, ensuring the deployment of PV systems is both promoted and economically viable, steering Spain closer to its renewable energy and sustainability aspirations. • Methodology for techno-economic analysis of residential rooftops' PV systems. • Hourly data is crucial for accurate PV potential forecasting. • Building typologies significantly influence PV generation potential. • Residential rural areas reach ∼50 % rooftop PV self-sufficiency; urban areas only 35 %. • Current feed-in tariff limits economic viability and deployment of residential PV. [ABSTRACT FROM AUTHOR]

Objectives: Validation of a pressure-standardized compression mammography (PSCM) system, which aims to reduce discomfort and pain by applying the same pressure to every breast, independent of breast size.Methods: We retrospectively studied mammograms of 39 patients acquired with a conventional force-standardized compression mammography (FSCM) technique and intra-individually compared them to mammograms acquired on a checkup visit with PSCM technique. Patients received one craniocaudal (CC) and one mediolateral oblique (MLO) compression for both breasts. All images were processed to obtain the contact area between the breast and the compression paddle. The pressure was calculated by dividing the compression force by the contact area.Results: A total of 150 FSCM and 150 PSCM images were analyzed. The mean pressure decreased significantly from 17.1 to 12.8 kPa (p < 0.001), when using PSCM instead of FSCM. The applied pressure hardly depended on the breast contact area with the paddle (-0.014 kPa/cm2), while a clear dependency was observed using FSCM. Furthermore, the relative number of over-compressions reduced from 26% to 2%, benefitting patients with smaller breasts.Conclusions: Our study suggests that using PSCM can reduce patient discomfort and pain during mammographic compression compared to conventional FSCM as a result of lower average pressure. Moreover, standardized pressure may provide a more constant image quality, which could improve diagnostic performance. [ABSTRACT FROM AUTHOR]

Abstract: The angular distribution in photon-jet production in is studied within a generalized factorization scheme taking into account the transverse momentum of the partons in the initial hadrons. Within this scheme an anomalously large asymmetry observed in the Drell–Yan process could be attributed to the T-odd, spin and transverse momentum dependent parton distribution function . This same function is expected to produce a asymmetry in the photon-jet production cross section. We give the expression for this particular azimuthal asymmetry, which is estimated to be smaller than the Drell–Yan asymmetry but still of considerable size for Tevatron kinematics. This offers a new possibility to study T-odd effects at the Tevatron. [Copyright &y& Elsevier]

Abstract: We consider polarized Λ hyperon production in proton–proton scattering, , in the kinematical region of the LHC experiments, in particular the ALICE experiment. We present a new Λ polarization observable that arises from the Sivers effect in the fragmentation process. It can be large even at midrapidity and therefore, is of interest for high energy hadron collider experiments. Apart from its potential to shed light on the mechanisms behind the phenomenon of Λ polarization arising in unpolarized hadronic collisions, the proposed observable in principle also allows to test the possible color flow dependence of single spin asymmetries and the (non)universality of transverse momentum dependent fragmentation functions. [Copyright &y& Elsevier]

We analyze the transverse-momentum-dependent distribution and fragmentation functions in space-like and time-like hard processes involving at least two hadrons, in particular, 1-particle inclusive leptoproduction, the Drell–Yan process and two-particle inclusive hadron production in electron–positron annihilation. As is well known, transverse momentum dependence allows for the appearance of unsuppressed single spin azimuthal asymmetries, such as Sivers and Collins asymmetries. Recently, Belitsky, Ji and Yuan obtained fully color-gauge-invariant expressions for the relevant matrix elements appearing in these asymmetries at leading order in an expansion in the inverse hard scale. We rederive these results and extend them to observables at the next order in this expansion. We observe that at leading order one retains a probability interpretation, contrary to a claim in the literature and show the direct relation between the Sivers effect in single spin asymmetries and the Qiu–Sterman mechanism. We also study fragmentation functions, where the process-dependent gauge link structure of the correlators is not the only source of T-odd observables and discuss the implications for universality. [Copyright &y& Elsevier]

A gas chromatography/mass spectrometry (GC/MS) method for the quantification of para-fluorofentanyl (pFF) in powder and powdered samples was developed and validated. The method was applied on a seizure of capsules and tablets, that had been confiscated at an illicit production site in the Netherlands. The investigated capsules and tablets contained pFF in the range of 33.8–408.7 μg. As caffeine was detected as being an adulterant, a HPLC/UV method for the quantification of caffeine in capsules and tablets was also validated and applied. Caffeine was detected in the range of 25.6–108 mg per capsule or tablet. Based on an extrapolation of pharmacological and toxicological data of fentanyl, it can be argued that the highest detected single dose of pFF could be lethal, when administered orally. However, the large variability of the doses observed for pFF could mislead abusers, potentially leading to multiple doses and thus overdosing. [Copyright &y& Elsevier]

Multi-objective optimization (MOO) has emerged recently as a useful technique in the design and planning of engineering systems because it allows identifying alternatives leading to significant environmental savings. MOO models typically contain an infinite number of Pareto solutions, from which decision-makers should choose the best one according to their preferences. An approach is here presented that identifies and retains for further inspection a reduced set of Pareto solutions showing better overall performance. The capabilities of our approach are illustrated through its application to the design of reverse osmosis desalination plants considering simultaneously the unitary production cost and a set of environmental impacts in several damage categories. Our method reduces significantly the number of Pareto points, thereby facilitating the decision-making process in MOO. [ABSTRACT FROM AUTHOR]

Different head-and-neck positions (HNPs) are discussed in relation to potential welfare issues. To evaluate the effect on welfare, seven Royal Dutch Sport horses were studied in five predetermined HNPs: (1) unrestrained (HNP1); (2) neck raised, bridge of nose around the vertical (HNP2); (3) neck lowered and considerably flexed, bridge of nose pointing towards the chest (HNP4); (4) neck raised and extended, bridge of nose in front of the vertical (HNP5), and (5) neck lowered and flexed, bridge of nose pointing towards the carpus (HNP7). A standardised exercise test (SET) of 34 min consisted of trot, canter and walk. Behaviour was recorded with a pre-defined ethogram and R-R intervals measured using telemetry. Cortisol concentrations were taken at the start, 5 and 30 min after the SET. Behaviour around the SET was scored separately. Conflict behaviours increased significantly during HNP2 when compared with HNP1, HNP4 and HNP7 during the SET, and there was significant negative anticipation before HNP2 and HNP7. The heart rate variability (HRV) frequency domain for HNP2 showed a significantly increased low frequency peak (LFpeak) compared with other HNPs, and there was a decrease in very low frequency (VLF%) compared with HNP1. HNP4 showed a significant increase in LF% and decrease in VLF% compared with HNP1. Saliva cortisol concentrations were significantly increased in HNP2 at 5 and 30 min after exercise. Increased conflict behaviour was mostly observed in HNP2, but there was a raised HRV suggesting a sympathetic shift in HNP2 and HNP4, and increased cortisol concentrations during HNP2 indicated a stress response. [ABSTRACT FROM AUTHOR]

Abstract: The integrated gasification combined cycle (IGCC) is an electrical power generation system which offers efficient generation from coal with lower effect on the environment than conventional coal power plants. However, further improvement of its efficiency and thereby lowering emissions are important tasks to achieve a more sustainable energy production. In this paper, a process simulation tool is proposed for simulation of IGCC. This tool is used to improve IGCC''s efficiency and the environmental performance through an analysis of the operating conditions, together with process integration studies. Pinch analysis principles and process integration insights are then employed to make topological changes to the flowsheet to improve the energy efficiency and minimize the operation costs. Process data of the Texaco gasifier and the associated plants (coal preparation, air separation unit, gas cleaning, sulfur recovery, gas turbine, steam turbine and the heat recovery steam generator) are considered as a base case, and simulated using Aspen Plus®. The results of parameter analysis and heat integration studies indicate that thermal efficiency of 45% can be reached, while a significant decrease in CO2 and SO x emissions is observed. The CO2 and SO x emission levels reached are 698kg/MWh and 0.15kg/MWh, respectively. Application of pinch analysis determines energy targets, and also identifies potential modifications for further improvement to overall energy efficiency. Benefits of energy integration and steam production possibilities can further be quantified. Overall benefits can be translated to minimum operation costs and atmospheric emissions. [Copyright &y& Elsevier]