720 research outputs found
Searching for Non-monotonic Effects of Fiscal Policy: New Evidence
Data revisions and the availability of a longer sample offer the opportunity to reconsider empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a "large and persistent impulse," defined as one in which the full employment surplus, as a percentage of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less than complete, offset during expansions or contractions.
Searching for Non-Monotonic Effects of Fiscal Policy: New Evidence
Data revisions and the availability of a longer sample offer the opportunity to reconsider the empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a “large and persistent impulse”, defined as one in which the full employment surplus, as a percent of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less then complete, offset during expansions or contractions.Fiscal policy, national saving
Searching for Non-Monotonic Effects of Fiscal Policy: New Evidence
Data revisions and the availability of a longer sample offer the opportunity to reconsider the empirical findings that suggest that in the OECD countries national saving responds non-monotonically to fiscal policy. The paper confirms that the circumstance most likely to give rise to a non-monotonic response of national saving to a fiscal impulse is a "large and persistent impulse", defined as one in which the full employment surplus, as a percent of potential output, changes by at least 1.5 percentage points per year over a two-year period. This particular circumstance remains the only statistically significant one even when we allow for non-monotonic responses to arise when public debt is growing rapidly or interest rate spreads are widening. We find that non-monotonic responses are similar for fiscal contractions and expansions. In particular, an increase in net taxes has no effect on national saving during large fiscal contractions or expansions. For government consumption there is a large, albeit in some specifications less then complete, offset during expansions or contractions.
Culture conditions influence satellite cell activation and survival of single myofibers
Single myofiber isolation protocols allow to obtain an in vitro system in which the physical association between the myofiber and its stem cells, the satellite cells, is adequately preserved. This technique is an indispensable tool by which the muscle regeneration process can be recapitulated and studied in each specific phase, from satellite cell activation to proliferation, from differentiation to fusion. This study aims to clarify the effect of different culture conditions on single myofibers, their associated satellite cells, and the physiological behavior of the satellite cells upon long term culture. By direct observations of the cultures, we compared different experimental conditions and their effect on both satellite cell behavior and myofiber viability
Targeting PKCθ promotes satellite cell self-renewal
Skeletal muscle regeneration following injury depends on the ability of satellite cells (SCs) to proliferate, self-renew, and eventually differentiate. The factors that regulate the process of self-renewal are poorly understood. In this study we examined the role of PKCθ in SC self-renewal and differentiation. We show that PKCθ is expressed in SCs, and its active form is localized to the chromosomes, centrosomes, and midbody during mitosis. Lack of PKCθ promotes SC symmetric self-renewal division by regulating Pard3 polarity protein localization, without affecting the overall proliferation rate. Genetic ablation of PKCθ or its pharmacological inhibition in vivo did not affect SC number in healthy muscle. By contrast, after induction of muscle injury, lack or inhibition of PKCθ resulted in a significant expansion of the quiescent SC pool. Finally, we show that lack of PKCθ does not alter the inflammatory milieu after acute injury in muscle, suggesting that the enhanced self-renewal ability of SCs in PKCθ-/- mice is not due to an alteration in the inflammatory milieu. Together, these results suggest that PKCθ plays an important role in SC self-renewal by stimulating their expansion through symmetric division, and it may represent a promising target to manipulate satellite cell self-renewal in pathological conditions
Pharmacological inhibition of PKCθ counteracts muscle disease in a mouse model of duchenne muscular dystrophy
Inflammation plays a considerable role in the progression of Duchenne Muscular Dystrophy (DMD), a severe muscle disease caused by a mutation in the dystrophin gene. We previously showed that genetic ablation of Protein Kinase C θ (PKCθ) in mdx, the mouse model of DMD, improves muscle healing and regeneration, preventing massive inflammation. To establish whether pharmacological targeting of PKCθ in DMD can be proposed as a therapeutic option, in this study we treated young mdx mice with the PKCθ inhibitor Compound 20 (C20). We show that C20 treatment led to a significant reduction in muscle damage associated with reduced immune cells infiltration, reduced inflammatory pathways activation, and maintained muscle regeneration. Importantly, C20 treatment is efficient in recovering muscle performance in mdx mice, by preserving muscle integrity. Together, these results provide proof of principle that pharmacological inhibition of PKCθ in DMD can be considered an attractive strategy to modulate immune response and prevent the progression of the disease
Os dois lados da mesma moeda: identificando os paradoxos da tecnologia no consumo online dos brasileiros
 The possibility of buying at any time of the day, researching prices and finding varied products are some of the advantages informed by online consumers. Despite the benefits, some disadvantages are also cited by these consumers, such as the impossibility of product experimentation, delay in delivery, difficulty in accessing websites and lack of security. With this, the possibility of paradoxical behavior among this type of consumer is verified. Therefore, this work aims to verify the presence of technology paradoxes in online consumer behavior. This is a descriptive-exploratory research, with a quantitative approach and a survey research method. A questionnaire was elaborated aiming to collect information regarding the profile of the online consumers interviewed and the characteristics of the purchase process, besides containing 28 statements referring to the 14 paradoxes of technology adapted from national surveys for consumption through the internet. A total of 263 respondents were obtained, where two pairs of paradoxes were present: Assimilation / Isolation and Planning / Improvisation.A possibilidade de comprar a qualquer hora do dia, pesquisar preços e encontrar produtos variados sĂŁo algumas das vantagens informadas por usuários do mercado online. Apesar dos benefĂcios, algumas desvantagens tambĂ©m sĂŁo citadas por esses consumidores, tais como a impossibilidade de experimentação do produto, demora para entrega, dificuldade de acesso a sites e falta de segurança. Com isso, verifica-se a possibilidade de comportamento paradoxal entre este tipo de consumidor. Portanto, este trabalho tem por objetivo verificar a presença de paradoxos da tecnologia no comportamento dos consumidores online. Trata-se de uma pesquisa descritiva-exploratĂłria, com abordagem quantitativa e mĂ©todo de pesquisa survey. Um questionário foi elaborado visando coletar informações referentes ao perfil dos consumidores online entrevistados e Ă s caracterĂsticas do processo de compra, alĂ©m de conter 28 afirmativas referentes aos 14 paradoxos da tecnologia adaptados de pesquisas nacionais para o consumo via internet. Obteve-se um total de 263 respondentes, onde se verificou a presença de dois pares de paradoxos: Integração/Isolamento e Planejamento/Improvisação
Development of Quantitative Structure-Property Relationships (QSPR) using calculated descriptors for the prediction of the physico-chemical properties (nD, r, bp, e and h) of a series of organic solvents.
Quantitative structure-property relationship (QSPR) models were derived for predicting boiling point (at 760 mmHg), density (at 25 \ub0C), viscosity (at 25 \ub0C), static dielectric constant (at 25 \ub0C), and refractive index (at 20 \ub0C) of a series of pure organic solvents of structural formula X-CH2CH2-Y. A very large number of calculated molecular descriptors were derived by quantum chemical methods, molecular topology, and molecular geometry by using the CODESSA software package. A comparative analysis of the multiple linear regression techniques (heuristic and best multilinear regression) implemented in CODESSA, with the multivariate PLS/GOLPE method, has been carried out. The performance of the different regression models has been evaluated by the standard deviation of prediction errors, calculated for the compounds of both the training set (internal validation) and the test set (external validation). Satisfactory QSPR models, from both predictive and interpretative point of views, have been obtained for all the studied properties
Passive Sampling of Organic Contaminants as a Novel Approach to Monitor Seawater Quality in Aquarium Ocean Tanks
The determination of trace pollutants in seawater is challenging, and sampling is a crucial step in the entire analytical process. Passive samplers combine in situ sampling and preconcentration, thus limiting the tedious treatment steps of the conventional sampling methods. Their use to monitor water quality in confined marine environment could bring several advantages. In this work, the presence of organic contaminants at trace and ultra-trace levels was assessed in the Genoa Aquarium supply-and-treated water using Polar Organic Integrative Samplers (POCIS). Both untargeted gas chromatography-mass spectrometry and targeted liquid chromatography-tandem mass spectrometry were employed. The untargeted approach showed the presence of hydrocarbons, diphenyl sulfone and 2,4-di-tert-butyl-phenol. Only hydrocarbons were detected in all the samples. Nineteen emerging contaminants, belonging to different classes (pharmaceuticals, UV-filters, hormones and perfluorinated compounds), were selected for the target analysis. Thirteen analytes were detected, mainly in supply water, even though the majority of them were below the quantitation limit. It is worthy to note that two of the detected UV-filters had never been reported in seawater using the POCIS samplers. The comparison of the analytes detected in supply and treated water indicated a good performance of the Aquarium water treatment system in the abatement of seawater contaminants
Splenic Ly6Chi monocytes are critical players in dystrophic muscle injury and repair
Dystrophic muscle is characterised by chronic injury, and a steady recruitment of inflammatory Ly6Chi monocytes. Recent studies have identified the spleen as the dominant reservoir of these cells during chronic inflammation. Here we investigated the hitherto unexplored contribution of splenic Ly6Chi monocytes to dystrophic muscle pathology. Using the mdx mouse model of muscular dystrophy, we show that Ly6Chi monocytes accumulate in great numbers in the spleen over the course of the disease. The chemokine receptor CCR2 was upregulated on Ly6Chi monocytes in mdx spleen before disease onset, thereby enabling their recruitment to dystrophic muscle. Splenectomy performed before disease onset significantly reduced the number of Ly6Chi monocytes infiltrating dystrophic limb muscle. Moreover, in the absence of splenic Ly6Chi monocytes there was a significant reduction in dystrophic muscle inflammation and necrosis, along with improved regeneration during early disease. However, during late disease, lack of splenic Ly6Chi monocytes adversely affected muscle fiber repair, due to a delay in the phenotypic shift of pro-inflammatory F4/80+/Ly6Chi/CD206lo to anti-inflammatory F4/80+/Ly6Clo/CD206+ macrophages. Overall, we show that the spleen is an indispensable source of Ly6Chi monocytes in muscular dystrophy, and that splenic monocytes are critical players in both muscle fiber injury and repair
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