3,237 research outputs found
Tax Reforms and Network Effects
This paper investigates the effects of a tax reform that eliminates tax rate heterogeneity and cumulative taxation using a general equilibrium model with multiple sectors with market power. Industries are connected through input-output linkages, and changes in taxation are not confined within industries. We calibrate the model to Brazil, a country with a highly distorted tax system. The revenue-neutral tax reform generates gains of 7.8% of GDP and 1.9% of welfare. Just eliminating VAT rate dispersion leads to a 5.9% increase in GDP. Due to propagation effects, in 10 sectors direct taxes increased but output and profits did not fall
Resistance Spot Welding of Dissimilar Steels: Temperature Curves
Resistance spot welding was used to joint AISI 316L austenitic stainless steel and AISI 1020 low carbon steel. During the welding process, temperature measurements were taken to obtain the temperature curves. Because of the different chemical compositions of the carbon steel and stainless steels, their thermal conductivity values are also different. Electrical resistivity is also an important parameter when carbon steel is spot welded to stainless steel. Differences in the thermal conductivity and in the electrical resistivity of metals lead to an asymmetrical weld nugget in the dissimilar joints. Dissimilar resistance spot welding can be more complex than similar welding due to different thermal cycle experienced with each metal
Changes in the Semantic Construction of Compassion after the Cognitively-Based Compassion Training (CBCT®) in Women Breast Cancer Survivors
The growing body of research on compassion has demonstrated its benefits for healthcare and wellbeing. However, there is no clear agreement about a definition for compassion, given the novelty of the research on this construct and its religious roots. The aim of this study is to analyze the mental semantic construction of compassion in Spanish-speaking women breast cancer survivors, and the effects of the Cognitively-Based Compassion Training (CBCT®) on the modification of this definition, compared to treatment-as-usual (TAU), at baseline, post-intervention, and six-month follow-up. Participants were 56 women breast cancer survivors from a randomized clinical trial. The Osgood''s Semantic Differential categories (evaluative, potency, and activity scales) were adapted to assess the semantic construction of compassion. At baseline, participants had an undefined idea about compassion. The CBCT influenced subjects'' semantic construction of what it means to be compassionate. Findings could lead to future investigations and compassion programs that adapt to a specific culture or population. © Universidad Complutense de Madrid and Colegio Oficial de Psicólogos de Madrid 2021
Towards ai-based interactive game intervention to monitor concentration levels in children with attention deficit
—Preliminary results to a new approach for neurocognitive training on academic engagement and monitoring of attention levels in children with learning difficulties is presented. Machine Learning (ML) techniques and a Brain-Computer Interface (BCI) are used to develop an interactive AI-based game for educational therapy to monitor the progress of children’s concentration levels during specific cognitive tasks. Our approach resorts to data acquisition of brainwaves of children using electroencephalography (EEG) to classify concentration levels through model calibration. The real-time brainwave patterns are inputs to our game interface to monitor concentration levels. When the concentration drops, the educational game can personalize to the user by changing the challenge of the training or providing some new visual or auditory stimuli to the user in order to reduce the attention loss. To understand concentration level patterns, we collected brainwave data from children at various primary schools in Brazil who have intellectual disabilities e.g. autism spectrum disorder and attention deficit hyperactivity disorder. Preliminary results show that we successfully benchmarked (96%) the brainwave patterns acquired by using various classical ML techniques. The result obtained through the automatic classification of brainwaves will be fundamental to further develop our full approach. Positive feedback from questionnaires was obtained for both, the AI-based game and the engagement and motivation during the training sessions
Compassion-based meditation quality practice and its impact on the positive attitudes toward others
Objectives: The authors report on the initial development and validation of the Compassion Practice Quality Scale (CPQS), a measure to assess the quality of compassion-based meditation (CBM). It is conceptualized and operationalized via two factors measuring mental imagery and somatic perception/response. Methods: The total sample was composed of 205 university students who underwent a CBM and completed pre-test/post-test assessment of compassion and related constructs. Results from a series of preliminary psychometric analyses of the CPQS were examined, including factor analysis, internal consistency, and convergent/discriminant validity. Results: The data supported a 12-item and 10-item (without reference to gestures and self-instructions) CPQS of which imagery and somatic perception emerged as two significant reliable subscales, with Cronbach’s alpha values of.90 and.88 respectively. Practice quality factors assessed by the CPQS correlated in expected ways with fear of compassion, imagery variables, and self-criticism, as well as predicted compassion outcome (i.e., feeling positive attitudes toward others). Conclusions: Our findings contribute to identifying two key components of high-quality meditation in CBM (i.e., mental imagery and somatic perception/response) for use in pedagogical development and further research and to offer a reliable self-report measure to assess them for the first time. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
Bioactivity of semisynthetic eugenol derivatives against Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae infesting maize in Colombia
The anti-acetylcholinesterase, larvicidal, antifeedant activities and general toxicity of 15 semisynthetic eugenol derivatives based on clove oil (including the own oil), were evaluated against the maize armyworm, Spodoptera frugiperda (J.E. Smith). Therefore, promising eugenol molecules were classified with larvicidal, anti-acetylcholinesterase and antifeedant activities for controlling this pest. During structure–activity relationship studies and physicochemical profile analysis, it was found that among tested molecules 1-15, eugenol 1, prenyl eugenol 4, isoeugenol 8 and isoeugenol acetate 11 exhibited lethal effects LD50 at concentrations < 1 mg/g of insect. On the other hand, eugenol 1, metallyl eugenol 3, isoeugenol 8 and isoeugenol acetate 11 showed a good antifeedant activity (CE50 =158-209 µg/mL) with a high antifeedant index (70-78 %) at concentration 1000 µg/mL, possessing a weak antiacetylcholinesterase activity (IC50 = 21-31 g/mL). According to their ecotoxicological profiles (LC50 = 2033.1-6303.8 µg/mL on Artemia salina larvae), isoeugenol 8 and its acetate derivative 11 could be potential used in control of the growth, feeding, or reproduction of S. frugiperda larvae, acting as moderate insecticidal acetylcholinesterase inhibitors and/or antifeedant molecules. Such structure–activity relationship studies could stimulate the identification of lead structures from natural sources for the development of larvicidal and deterrent products against S. frugiperda and related insect pests.Fil: Vargas MĂ©ndez, Leonor Y.. Universidad Santo Tomás; ColombiaFil: Sanabria FlĂłrez, Pedro L.. Universidad Santo Tomás; ColombiaFil: Saavedra Reyes, Laura Marcela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata. Instituto de Investigaciones FisicoquĂmicas TeĂłricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones FisicoquĂmicas TeĂłricas y Aplicadas; Argentina. Universidad Santo Tomás; ColombiaFil: Merchan Arenas, Diego R.. Universidad Industrial Santander; ColombiaFil: Kouznetsov, Vladimir V.. Universidad Industrial Santander; Colombi
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