199 research outputs found

    Definable orthogonality classes in accessible categories are small

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    We lower substantially the strength of the assumptions needed for the validity of certain results in category theory and homotopy theory which were known to follow from Vopenka's principle. We prove that the necessary large-cardinal hypotheses depend on the complexity of the formulas defining the given classes, in the sense of the Levy hierarchy. For example, the statement that, for a class S of morphisms in a locally presentable category C of structures, the orthogonal class of objects is a small-orthogonality class (hence reflective) is provable in ZFC if S is \Sigma_1, while it follows from the existence of a proper class of supercompact cardinals if S is \Sigma_2, and from the existence of a proper class of what we call C(n)-extendible cardinals if S is \Sigma_{n+2} for n bigger than or equal to 1. These cardinals form a new hierarchy, and we show that Vopenka's principle is equivalent to the existence of C(n)-extendible cardinals for all n. As a consequence, we prove that the existence of cohomological localizations of simplicial sets, a long-standing open problem in algebraic topology, is implied by the existence of arbitrarily large supercompact cardinals. This result follows from the fact that cohomology equivalences are \Sigma_2. In contrast with this fact, homology equivalences are \Sigma_1, from which it follows (as is well known) that the existence of homological localizations is provable in ZFC.Comment: 38 pages; some results have been improved and former inaccuracies have been correcte

    Comparing climatic suitability and niche distances to explain populations responses to extreme climatic events

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    Habitat suitability calculated from Species Distribution Models (SDMs) has been used to assess population performance, but empirical studies have provided weak or inconclusive support to this approach. Novel approaches measuring population distances to niche centroid and margin in environmental space have been recently proposed to explain population performance, particularly when populations experience exceptional environmental conditions that may place them outside of the species niche. Here, we use data of co-occurring species’ decay, gathered after an extreme drought event occurring in the SE of the Iberian Peninsula which highly affected rich semiarid shrubland communities, to compare the relationship between population decay (mortality and remaining green canopy) and (1) distances between populations’ location and species niche margin and centroid in the environmental space, and (2) climatic suitability estimated from frequently used SDMs (here MaxEnt) considering both the extreme climatic episode and the average reference climatic period before this. We found that both SDMs-derived suitability and distances to species niche properly predict populations performance when considering the reference climatic period; but climatic suitability failed to predict performance considering the extreme climate period. In addition, while distance to niche margins accurately predict both mortality and remaining green canopy responses, centroid distances failed to explain mortality, suggesting that indexes containing information about the position to niche margin (inside or outside) are better to predict binary responses. We conclude that the location of populations in the environmental space is consistent with performance responses to extreme drought. Niche distances appear to be a more efficient approach than the use of climate suitability indices derived from more frequently used SDMs to explain population performance when dealing with environmental conditions that are located outside the species environmental niche. The use of this alternative metrics may be particularly useful when designing conservation measures to mitigate impacts of shifting environmental conditions

    Aspects of Thermodynamics of Deoxidation of Molten Steel with Mn and A1

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    Employing data from different sources, variations in the relationship between dissolved oxygen and dissolved element for deoxiation by Al, Si and Mn have been asse-ssed. Thermodynamic calculations have been performed for simultaneous deoxidation by Al+Si and Mn have been perf-ormed for simultaneous deoxidation by Ai+Si+Mn and equil-ibrium compositions of the metal have been determined for various compositions of the metal have been determined for various compositions of slag consisting of MnO, SiO2 and Al203. Some calculated values have been compared with those reported in literature

    Синтез та характеристика екологічно чистої та схильної до біологічного розкладання плівки ізоляту соєвого білка

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    У дослідженні біосумісна та схильна до біологічного розкладання плівка ізоляту соєвого білка (SPI) була розроблена шляхом включення полярних компонентів за допомогою техніки лиття. Вплив додаткових компонентів (гліцерин, сорбітол та поліетиленгліколь) з SPI аналізували за допомогою скануючої електронної мікроскопії (SEM), інфрачервоної спектроскопії з перетворенням Фур'є (FTIR) та рентгенівської дифракції (XRD). Результат підтвердив, що включення полярних компонентів з ізолятом соєвого білка демонструє сильну міжмолекулярну взаємодію. Це найпростіший метод розробки біосумісних плівок, які мають широке застосування в біомедицині, біотехнології, безпеці харчових продуктів та промисловості їх пакування.In the current study, biocompatible and biodegradable soy protein isolate (SPI) based film was developed by incorporating polar components using casting technique. The effects of additive components (glycerol, sorbitol and polyethylene glycol) with SPI were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The result confirmed that the incorporation of polar components with soy protein isolate exhibits strong intermolecular interaction. This is the easiest method to develop biocompatible films that have wide applications in biomedical, biotechnology, food safety and food packaging industries

    Definable orthogonality classes in accessible categories are small

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    We lower substantially the strength of the assumptions needed for the validity of certain results in category theory and homotopy theory which were known to follow from Vopěnka's principle. We prove that the necessary large-cardinal hypotheses depend on the complexity of the formulas defining the given classes, in the sense of the Lévy hierarchy. For example, the statement that, for a class S of morphisms in a locally presentable category C of structures, the orthogonal class of objects is a small-orthogonality class (hence reflective) can be proved in ZFC if S is Σ1, while it follows from the existence of a proper class of supercompact cardinals if S is Σ2, and from the existence of a proper class of what we call C(n)-extendible cardinals if S is Σn+2 for n≥1. These cardinals form a new hierarchy, and we show that Vopěnka's principle is equivalent to the existence of C(n)-extendible cardinals for all n. As a consequence of our approach, we prove that the existence of cohomological localizations of simplicial sets, a long-standing open problem in algebraic topology, is implied by the existence of arbitrarily large supercompact cardinals. This follows from the fact that E∗-equivalence classes are Σ2, where E denotes a spectrum treated as a parameter. In contrast with this fact, E∗-equivalence classes are Σ1, from which it follows (as is well known) that the existence of homological localizations is provable in ZFC

    A Community Program of Integrated Care for Frail Older Adults : +AGIL Barcelona

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    Objectives: To assess the 3-month impact on physical function of a program for community-dwelling frail older adults, based on the integration of primary care, geriatric medicine, and community resources, implemented in \u201creal life\u201d. Design: Interventional cohort study. Setting: Primary care in Barcelona, Spain. Participants: Individuals aged 6580 years (n=134), presenting at least one sign of frailty (i.e., slow gait speed, weakness, memory complaints, involuntary weight loss, poor social support). Intervention: After frailty screening by the primary care team, candidates were referred to a geriatric team (geriatrician + physical therapist), who performed a comprehensive geriatric assessment and designed a tailored multidisciplinary intervention in the community, including a) multi-modal physical activity (PA) sessions, b) promotion of adherence to a Mediterranean diet c) health education and d) medication review. Measurements: Participants were assessed based on a comprehensive geriatric assessment including physical performance (Short Physical Performance Battery -SPPB- and gait speed), at baseline and at a three month follow-up. Results: A total of 112 (83.6%) participants (mean age=80.8 years, 67.9% women) were included in this research. Despite being independent in daily life, participants\u2019 physical performance was impaired (SPPB=7.5, SD=2.1, gait speed=0.71, SD=0.20 m/sec). After three months, 90.2% of participants completed 657.5 physical activity sessions. The mean improvements were +1.47 (SD 1.64) points (p<0.001) for SPPB, +0.08 (SD 0.13) m/sec (p<0.001) for gait speed, 125.5 (SD 12.10) sec (p<0.001) for chair stand test, and 53% (p<0.001) improved their balance. Results remained substantially unchanged after stratifying the analyses according to the severity of frailty. Conclusions: Our results suggested that a \u201creal-world\u201d multidisciplinary intervention, integrating primary care, geriatric care, and community services may improve physical function, a marker of frailty, within 3 months. Further studies are needed to address the long-term impact and scalability of this implementation program

    A Community Program of Integrated Care for Frail Older Adults: +AGIL Barcelona

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    Objectives: To assess the 3-month impact on physical function of a program for community-dwelling frail older adults, based on the integration of primary care, geriatric medicine, and community resources, implemented in 'real life'. Design: Interventional cohort study. Setting: Primary care in Barcelona, Spain. Participants: Individuals aged ≥80 years (n=134), presenting at least one sign of frailty (i.e., slow gait speed, weakness, memory complaints, involuntary weight loss, poor social support). Intervention: After frailty screening by the primary care team, candidates were referred to a geriatric team (geriatrician + physical therapist), who performed a comprehensive geriatric assessment and designed a tailored multidisciplinary intervention in the community, including a) multi-modal physical activity (PA) sessions, b) promotion of adherence to a Mediterranean diet c) health education and d) medication review. Measurements: Participants were assessed based on a comprehensive geriatric assessment including physical performance (Short Physical Performance Battery -SPPB- and gait speed), at baseline and at a three month follow-up. Results: A total of 112 (83.6%) participants (mean age=80.8 years, 67.9% women) were included in this research. Despite being independent in daily life, participants' physical performance was impaired (SPPB=7.5, SD=2.1, gait speed=0.71, SD=0.20 m/sec). After three months, 90.2% of participants completed ≥7.5 physical activity sessions. The mean improvements were +1.47 (SD 1.64) points (p<0.001) for SPPB, +0.08 (SD 0.13) m/sec (p<0.001) for gait speed, -5.5 (SD 12.10) sec (p<0.001) for chair stand test, and 53% (p<0.001) improved their balance. Results remained substantially unchanged after stratifying the analyses according to the severity of frailty. Conclusions: Our results suggested that a 'real-world' multidisciplinary intervention, integrating primary care, geriatric care, and community services may improve physical function, a marker of frailty, within 3 months. Further studies are needed to address the long-term impact and scalability of this implementation program

    An Eco-Friendly Synthesis Approach for Enhanced Photocatalytic and Antibacterial Properties of Copper Oxide Nanoparticles Using Coelastrella terrestris Algal Extract

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    Manisha Khandelwal,1 Sunita Choudhary,2 Harish,2 Ashok Kumawat,3 Kamakhya Prakash Misra,3 Yogeshwari Vyas,1 Bhavya Singh,4 Devendra Singh Rathore,4 Kanchan Soni,3 Ashima Bagaria,3 Rama Kanwar Khangarot1 1Department of Chemistry, University College of Science, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, India; 2Department of Botany, University College of Science, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, India; 3Department of Physics, School of Basic Sciences, Manipal University Jaipur, Jaipur, Rajasthan, 303007, India; 4Department of Environmental Sciences, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, IndiaCorrespondence: Rama Kanwar Khangarot, Department of Chemistry, University College of Science, Mohanlal Sukhadia University, Udaipur, Rajasthan, 313001, India, Email [email protected]: In the current scenario, the synthesis of nanoparticles (NPs) using environmentally benign methods has gained significant attention due to their facile processes, cost-effectiveness, and eco-friendly nature.Methods: In the present study, copper oxide nanoparticles (CuO NPs) were synthesized using aqueous extract of Coelastrella terrestris algae as a reducing, stabilizing, and capping agent. The synthesized CuO NPs were characterized by X-ray diffraction (XRD), UV-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and field emission scanning electron microscopy (FE-SEM) coupled with energy-dispersive X-ray spectroscopy (EDS).Results: XRD investigation revealed that the biosynthesized CuO NPs were nanocrystalline with high-phase purity and size in the range of 4.26 nm to 28.51 nm. FTIR spectra confirmed the existence of secondary metabolites on the surface of the synthesized CuO NPs, with characteristic Cu–O vibrations being identified around 600 cm− 1, 496 cm− 1, and 440 cm− 1. The FE-SEM images predicted that the enhancement of the algal extract amount converted the flattened rice-like structures of CuO NPs into flower petal-like structures. Furthermore, the degradation ability of biosynthesized CuO NPs was investigated against Amido black 10B (AB10B) dye. The results displayed that the optimal degradation efficacy of AB10B dye was 94.19%, obtained at 6 pH, 50 ppm concentration of dye, and 0.05 g dosage of CuO NPs in 90 min with a pseudo-first-order rate constant of 0.0296 min− 1. The CuO-1 NPs synthesized through algae exhibited notable antibacterial efficacy against S. aureus with a zone of inhibition (ZOI) of 22 mm and against P. aeruginosa with a ZOI of 17 mm.Conclusion: Based on the findings of this study, it can be concluded that utilizing Coelastrella terrestris algae for the synthesis of CuO NPs presents a promising solution for addressing environmental contamination. Keywords: green synthesis, CuO NPs, photocatalysis, antibacterial activity, wastewater treatmen

    Securing Smart Contract On The Fly

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    We present Solythesis, a source to source Solidity compiler which takes a smart contract code and a user specified invariant as the input and produces an instrumented contract that rejects all transactions that violate the invariant. The design of Solythesis is driven by our observation that the consensus protocol and the storage layer are the primary and the secondary performance bottlenecks of Ethereum, respectively. Solythesis operates with our novel delta update and delta check techniques to minimize the overhead caused by the instrumented storage access statements. Our experimental results validate our hypothesis that the overhead of runtime validation, which is often too expensive for other domains, is in fact negligible for smart contracts. The CPU overhead of Solythesis is only 0.12% on average for our 23 benchmark contracts

    Health Impacts of Catastrophic Climate Change: Expert Workshop. Avoid Dangerous Climate Change (AVOID)

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    Climate change is likely to have serious and significant impacts on human population health. The mechanisms by which climate change may affect health are becoming better understood. Current quantitative methods of estimating future health impacts rely on disease-specific models that primarily describe relationships between mean values of weather variables and health outcomes and do not address the impacts of extreme events or weather disasters. Extreme events have the potential to disrupt community function, which is of concern for decision-makers. Estimating the magnitude and extent of impacts from low probability high impact events is challenging because there is often no analogue that can provide relevant evidence and that take into account the complexity of factors determining future vulnerability and health impacts (the social determinants of health)
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