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Economic change and cultural evolution: the ultimate influence of human cognitive limitations
No full textHow cognitive limitations of individuals may affect the dynamics of cultural evolution under the effects of economic and technological forces is explored here. In particular, the extraordinary economic growth during the industrial and scientific revolutions of the last two centuries has been accompanied by an extraordinary acceleration of cultural changes. We will propose that these changes are due to competition, decay and replacement processes among the different kinds of cultural contents, ultimately resulting from our cognitive limitations. Different laws have been proposed recently for the decay of individualized cultural items and for the underlying competition processes, which will be discussed herein. With respect to the informational/cognitive limitations of individuals, the cognitive psychology views will be complemented—and somehow quantified—from the angle of the “social brain” or “sociotype” hypothesis. The generational phenomenon also emerges, by which differentiated generations develop a remarkable divergence in ways of life, aspirations, ideals, values, and often in the use of communication technologies. It is in this interactive individual–generational context of competitive processes that the acceleration of cultural change during the few last decades might be investigated by considering the vastly increased economic output and the widespread use of new communication technologies
Electrically-driven control of nanoscale chemical changes in amorphous complex oxide memristive devices
No full textIn this paper we investigate the electrical response response of amorphous complex oxide memristors under different electrical stimulation. With the help of transmission electron microscopy and energy dispersive x-ray spectroscopy, we observed that those devices stimulated with voltage display strong cationic segregation at the nanoscale together with the partial crystallization of the oxide layer. On the other hand, devices stimulated with current maintain their amorphous character with no significative chemical changes. Our analysis also shows that current stimulation leads to a more stable memristive response with smaller cycle-to-cycle variations. These findings could contribute to the design of more reliable oxide-based memristors and underscore the crucial effect that has type of electrical stimulation applied to the devices has on their integrity and reliability
A spatially explicit containment modelling approach for escaped wildfires in a Mediterranean climate using machine learning
No full textWildfires are particularly prevalent in the Mediterranean, being expected to increase in frequency due to the expected increase in regional temperatures and decrease in precipitation. Effectively suppressing large wildfires requires a thorough understanding of containment opportunities across landscapes, to which empirical spatial modelling can contribute largely. The previous containment model in Catalonia failed to account for the crucial roles of weather conditions, lacked temporal prediction and could not forecast windows for containment opportunities, prompting this research. We employed a detailed geospatial approach to assess the spatial-temporal variations in containment probability for escaped wildfires in Catalonia. Using machine learning algorithms, geospatial data, and 124 historical wildfire perimeters from 2000 to 2015, we developed a predictive model with high accuracy (Area Under the Receiver Operating Characteristics Curve = 0.81 ± 0.03) over 32,108 km2 at a 30-meter resolution. Our analysis identified agricultural plains near non-burnable barriers, such as major road corridors, as having the highest containment probability. Conversely, steep mountainous regions with limited accessibility exhibited lower containment success rates. We also found temperature and windspeed to be critical factors influencing containment success. These findings inform optimal firefighting resource allocation and contribute to strategic fuel management initiatives to enhance firefighting operations
Cross-Dehydrogenative Coupling of Secondary Amines with Silanes Catalyzed by Agostic Iridium-NSi Species
No full textAn active catalytic system for the cross-dehydrogenative coupling (CDC) of a wide range of secondary amines with silanes is reported. The iridium(III) derivatives [Ir(H)(X)(κ2-NSiDMQ)(L)] (NSiDMQ = {4,8-dimethylquinoline-2-yloxy}dimethylsilyl; L = coe, X = Cl, 2; L = coe, X = OTf, 3; L = PCy3, X = Cl, 4; L = PCy3, X = OTf, 5), which are stabilized by a weak yet noticeable Ir···H–C agostic interaction between the iridium and one of the C–H bonds of the 8-Me substituent of the NSiDMQ ligand, have been prepared and fully characterized. These species have proven to be effective catalysts for the CDC of secondary amines with hydrosilanes. The best catalytic performance (TOF1/2 = 79,300 h–1) was obtained using 5 (0.25 mol %), N-methylaniline, and HSiMe2Ph. The catalytic activity of the species [Ir(H)(OTf)(κ2-NSiQ)(PCy3)] (10, NSiQ = {quinoline-2-yloxy}dimethylsilyl) and [Ir(H)(OTf)(κ2-NSiMQ)(PCy3)] (11, NSiMQ = {4-methylquinoline-2-yloxy}dimethylsilyl), related to 5 but lacking the 8-Me substituent, is markedly lower than that found for 5. This fact highlights the crucial role of the 8-Me substituent of the NSiDMQ ligand in enhancing the catalytic performance of these iridium complexes
Enhancing Sustainability with LCA: A Comparative Analysis of Design and Manufacturing Processes
Get PDFThis study evaluates the feasibility and effectiveness of the Life Cycle Assessment (LCA) methodology. Two widely used products with the same functionality but different designs and production processes were selected for comparative analysis. SimaPro 9.6.0 software was used for the calculations and LCA of both assemblies. The analysis covered all phases of the life cycle, taking into account factors such as energy, materials and water consumption. The results allowed a comparison of the environmental impacts of the two assemblies, identifying the life cycle phases with the highest impact and the most relevant impact categories. The analysis revealed that the metal trolley exhibited a 40% higher environmental impact during production compared to the polypropylene trolley, primarily due to the material extraction and processing phases. Additionally, the polypropylene trolley showed higher long-term impacts in landfill scenarios due to carcinogenic substance emissions. These findings highlight the significance of design and material selection in reducing environmental impacts. Applying the LCA methodology to the two mechanical assemblies allowed us to identify opportunities for improvement in the design and manufacturing processes, with the aim of reducing the environmental impact and increasing the competitiveness of the products. By considering the full life cycle of a product from the early design phases, more sustainable design and manufacturing decisions can be made, and by using this analysis, companies can develop more sustainable products and reduce costs
Specific Physical and Nutritional Preparation of a Professional Kata Karate Athlete: A Case Study with a Bronze Medallist from the Pan American Games
Get PDFBackground and objectives: In karate, particularly in the kata discipline, there is a notable lack of studies focused on specific physical preparation for competitions. This highlights an urgent need for more in-depth research into this crucial aspect of athletic training to optimize performance and athlete preparation. The objective of this study was to analyze the influence of a dietary plan combined with specific physical preparation on the performance and body composition of a professional kata athlete preparing for a Pan American championship. Methods: A 20-year-old elite female karateka (60.7 kg, 165.4 cm) followed a nutritional plan with an isocaloric diet. The strength and power of the upper and lower limbs were evaluated through countermovement jump (CMJ) and one-repetition maximum (1RM) tests in bench press and free squat over a five-month period before the competition. Results: Following the nutritional plan and physical preparation, the athlete’s body composition improved in terms of fat loss (from 12.17% to 10.68%) and increased muscle mass (from 51.45% to 53.09%). Moreover, these improvements translated into better performance in tests such as CMJ (from 38.29 cm to 44.14 cm), 1RM bench press (from 54.5 kg to 67.6 kg), and 1RM free squat (from 65.1 kg to 78.4 kg). Conclusions: This study demonstrates that a comprehensive approach to personalized physical, technical, and nutritional preparation over 16 weeks significantly improves muscle strength and performance in karate kata. The novelty of this intervention lies in the detailed description of the total workload, encompassing both physical and technical performance, with a specific plan tailored to the athlete’s needs. Additionally, the preparation was precisely designed for a specific tournament, addressing the sport’s unique demands
Household strategies for coping with energy poverty: Technological and socio-familial dilemmas
Get PDFThis paper describes the diverse and imaginative strategies adopted by socially vulnerable households in their day-to-day lives at the micro-level (a view from below) for coping with energy poverty. In addition, we identify the perceptions and narratives of these households regarding energy poverty, the condition of their building, and the social actors involved. The research has been conducted in the city of Zaragoza (Spain), a city severely affected by climate change. This is the first qualitative sociological study carried out in Spain with in-depth interviews at the household level, using qualitative analysis software. The results show the continuous dilemmas these households face to keep the dwelling at a comfortable temperature (both excess cold and excess heat, or energy saving): how and when to use technology and appliances, budgetary quandaries, leaning on ‘survival strategies’, dealing with frequent power supply cuts, changing energy service companies, or moving home. The three analytical dimensions considered – the socio-technical, the socio-spatial, and the socio-temporal – reveal that these dilemmas are frequently a source of stress and uncertainty, especially for those with members who have severe health issues, or who are minors, elderly or single mothers. Likewise, being aware of the importance of the rehabilitation of the buildings where they live is crucial for reducing energy consumption and, therefore, energy poverty. This research contributes to a more detailed understanding of this social problem (its visibility) and possible institutional initiatives for its palliation. The research hypotheses are useful for regions with similar climatic characteristic
Numerical investigation of the effect of the mushy zone parameter and the thermal properties of paraffin-based PCMss on solidification modeling under T-history conditions
No full textABSTRACTPhase change materials (PCMs) are widely used in various critical applications because of their capacity to store thermal energy and regulate temperature effectively. A review of the literature on PCM solidification and melting simulations reveals that the accuracy of these simulations is highly dependent on the input parameters and underlying assumptions used in the software. Among the key factors influencing precise simulation results are the parameter of mushy zone () and the thermal properties of the material. This study numerically investigated the impact of the and thermal properties on the solidification behavior of a paraffin in the test tube under T‐history conditions. The analysis was conducted using the commercial CFD software ANSYS Fluent and the enthalpy‐porosity method is applied to simulation the solidification process. To accurately reflect the conditions of the T‐history experiment, radiative heat transfer between surfaces was employed for the boundary conditions, ensuring a realistic representation of the experimental setup. An evaluation of four thermal properties—thermal conductivity, density, latent heat, and specific heat—indicates that while an increase in latent heat, density, and specific heat slows down the rate of solidification, an increase in thermal conductivity has the opposite effect, accelerating the solidification process. The results further emphasize that selecting an appropriate value for is crucial for achieving accurate solidification simulations. Increasing from to enhanced the prediction accuracy of the solidification time by 10%. Additionally, the mushy zone parameter significantly affects the shape and progression of solidification. As increases, solidification in the lower layers decreases, concentrating the process more in the layers adjacent to the cold wall
Burden of bacterial antimicrobial resistance among hospitalised patients in Spain: findings from three nationwide prospective studies
Get PDFBackground: Assessing the burden of antimicrobial resistance is essential to determine the magnitude of this problem and to set its priority. We aimed to estimate the burden of disease caused by multidrug-resistant microorganisms (MDRO) in hospitalised patients in Spain.
Methods: Three prospective nationwide studies were conducted in 2018, 2019 and 2023. All patients with a new diagnosis of infection with any of 10 selected MDROs plus Clostridioides difficile during the study period (one week in 2018 and 2019 and two weeks in 2023) were included. Patient demographic, and clinical outcomes were analysed, including incidence, crude all-cause 30-day mortality and years of life lost (YLL). These results were used to calculate weighted and seasonally adjusted annual estimates for the whole country
FoMO and socio-emotional e-competencies as predictors of media multitasking, phubbing and cybergossip in university students: transnational differences between Mexico and Spain by gender
No full textThere are clear signs of the growing use of the internet across all cultures, which generate new behaviors in the virtual environment such as media multitasking, phubbing, and cybergossip, all associated with online risks and less positive modes of socialization. FoMO (Fear of Missing Out) along with virtual emotional experiences could be relevant predictors, where literature suggests that FoMO is a trigger for problematic social media use, and socio‐emotional e‐competencies facilitate adaptive behaviors in virtual environments. Hence, understanding which variables predict these phenomena is crucial and whether they can be generalized across different countries. The objective of this study is to analyze whether two dimensions of socio‐personal development used to interact in virtual environments, FoMO (Fear of Missing Out) and socio‐emotional e‐competencies (e‐COM), are predictors of different cyberbehaviors (cybergossip, phubbing and media multitasking) in university students from two different countries. It also aims to verify if socio‐emotional e‐competencies act as a moderator of this relationship. In order to achieve this, we used a sample of 1524 university students from Mexico and Spain (19.74 years old). The results of the path analysis models show that FoMO is the strongest predictor of the three online behaviors regardless of country and gender, especially in the case of phubbing. In addition, socio‐emotional e‐competencies help to explain the behaviors in a differential way for each country, and the dimension of e‐self‐control of impulsivity plays a moderating role in FoMO in the case of phubbing and media multitasking. Some differences between countries and genders are discussed