2,082 research outputs found
Do product market regulations in upstream sectors curb productivity growth? Panel data evidence for OECD countries
The paper focuses on the influence of upstream competition for productivity outcomes in downstream sectors. This relation is illustrated with a neo-Schumpeterian theoretical model of innovation (Aghion et al., 1997) with market imperfections in the production of intermediate goods. In this context, upstream market imperfections create barriers to competition in downstream markets and upstream producers use their market power to share innovation rents sought by downstream firms. Thus, lack of competition in upstream markets curbs incentives to improve productivity downstream, negatively affecting productivity outcomes. We test this prediction by estimating an error correction model that differentiates the potential downstream effects of lack of upstream competition in situations close and far from the global technological frontier. We measure competition upstream with regulatory burden indicators derived from OECD data on sectoral product market regulation and the industry-level efficiency improvement and the distance to frontier variables by means of a multifactor productivity (MFP) index. Panel regressions are run for 15 OECD countries and 20 sectors over the 1985-2007 period with country, sector and year fixed effects. We find clear evidence that anticompetitive regulations in upstream sectors have curbed MFP growth downstream over the past 15 years. These effects tend to be strongest for observations (i.e. country/sector/period triads) that are close to the global technological frontier. Our results suggest that, measured at the average distance to frontier and average level of anticompetitive regulations, the marginal effect of increasing competition by easing such regulations is to increase MFP growth by between 1 and 1.5 per cent per year in the OECD countries covered by our sample. Our results are robust to changes in the way MFP and the regulatory burden indicators are constructed, as well as to variations in the sample of countries and/or sectors.Productivity, Growth, Regulations, Competition, Catch-up.
Prenatal experience with language shapes the brain
Human infants acquire language with notable ease compared to adults, but the neural basis of their remarkable brain plasticity for language remains little understood. Applying a scaling analysis of neural oscillations to address this question, we show that newborns' electrophysiological activity exhibits increased long-range temporal correlations after stimulation with speech, particularly in the prenatally heard language, indicating the early emergence of brain specialization for the native language.</p
Application of biotic and taxonomic distinctness indices in assessing the Ecological Quality Status of two coastal lakes: Caprolace and Fogliano lakes (Central Italy)
Marine biotic indices (AMBI, BENTIX) and the statistical tool M-AMBI (Multivariate AMBI) were applied as a comparative approach in assessing the Ecological Quality Status (EcoQS) of two Mediterranean coastal lakes (Caprolace and Fogliano lakes) situated in the Circeo National Park (Central Italy). The macrobenthic community was analysed using univariate indices (community structure), correspondence analysis (CA) and taxonomic distinctness indices (Delta(+) and Lambda(+)). The community composition showed a dominance of lagoonal species in both coastal lakes, while in Caprolace lake marine taxa were also found. Diversity index (H') complies to ranges found in Mediterranean lagoons and taxonomic distinctness indices demonstrated that taxonomy structure is in accordance with natural variability ranges. Principal component analysis (PCA) on chemical parameters of water and sediment showed that both coastal lakes differ mainly in their organic matter composition. In fact, the protein fraction of bio-polymeric carbon prevails in Fogliano lake, while the 'refractory' component represented by carbohydrate fraction is predominant in Caprolace lake. The difference between the two coastal lakes was also demonstrated by co-inertia analysis (COIA) performed using abundance of species and concentrations of chemical parameters. The results from the application of the three biotic indices do not highlight a clear distinction between the two lagoons. However, the AMBI index provided a more suitable evaluation of EcoQS corresponding to 'slightly polluted' lagoons while M-AMBI and moreover BENTIX indices indicated a worsening situation. The biotic indices are widely used in assessing the EcoQS in marine environments, but their proper application in transitional waters would depend on a resettlement; thresholds established in the biotic index scale values need to be modified according to natural variability of transitional waters referring to abiotic conditions and abundance of tolerant species. (C) 2008 Elsevier Ltd. All rights reserved
The ATLAS discovery potential for MSSM neutral Higgs bosons decaying to a mu+mu- pair in the mass range up to 130 GeV
Results are presented on the discovery potential for MSSM neutral Higgs
bosons in the Mh-{max}scenario. The region of large tan beta, between 15 and
50, and mass between ~ 95 and 130 GeV is considered in the framework of the
ATLAS experiment at the Large Hadron Collider (LHC), for a centre-of-mass
energy = 14 TeV. This parameter region is not fully covered by the present data
either from LEP or from Tevatron. The h/A bosons, supposed to be very close in
mass in that region, are studied in the channel h/A -> mu+mu- accompanied by
two b-jets. The study includes a method to control the most copious background,
Zo -> mu+mu- accompanied by two b-jets. A possible contribution of the H boson
to the signal is also considered
A Model of Vertical Oligopolistic Competition
This paper develops a model of successive oligopolies with endogenous market entry, allowing for varying degrees of product differentiation and entry costs in both markets. Our analysis shows that the downstream conditions dominate the overall profitability of the two-tier structure while
the upstream conditions mainly affect the distribution of profits. We compare the welfare effects of upstream versus downstream deregulation policies and show that the impact of deregulation may be overvalued when ignoring feedback effects from the other market. Furthermore, we analyze how different forms of vertical restraints influence the endogenous market structure and show when they are welfare enhancing
InfluĂȘncia da pressĂŁo na densidade e no teor de umidade de briquetes de diferentes resĂduos de biomassa florestal.
Resumo
Wavelength dependent optical enhancement of superconducting interlayer coupling in La1.885Ba0.115CuO4
We analyze the pump wavelength dependence for the photo-induced enhancement
of interlayer coupling in La1.885Ba0.115CuO4, which is promoted by optical
melting of the stripe order. In the equilibrium superconducting state (T < Tc =
13 K), in which stripes and superconductivity coexist, time-domain THz
spectroscopy reveals a photo-induced blue-shift of the Josephson Plasma
Resonance after excitation with optical pulses polarized perpendicular to the
CuO2 planes. In the striped, non-superconducting state (Tc < T < T_SO = 40 K) a
transient plasma resonance similar to that seen below Tc appears from a
featureless equilibrium reflectivity. Most strikingly, both these effects
become stronger upon tuning of the pump wavelength from the mid-infrared to the
visible, underscoring an unconventional competition between stripe order and
superconductivity, which occurs on energy scales far above the ordering
temperature.Comment: 18 pages, 6 figure
The Italian registry of cystic echinococcosis (RIEC): the first prospective registry with a European future
n/
Anxiety-like behavior of prenatally stressed rats is associated with a selective reduction of glutamate release in the ventral hippocampus
Abnormalities of synaptic transmission and plasticity in the hippocampus represent an integral part of the altered programming triggered by early life stress. Prenatally restraint stressed (PRS) rats develop long-lasting biochemical and behavioral changes, which are the expression of an anxious/depressive-like phenotype. We report here that PRS rats showed a selective impairment of depolarization- or kainate-stimulated glutamate and 3HD-aspartate release in the ventral hippo campus, a region encoding memories related to stress and emotions. GABA release was un affected in PRS rats. As a consequence of reduced glutamate release, PRS rats were also highly resistant to kainate-induced seizures. Abnormalities of glutamate release were associated with large reductions in the levels of synaptic vesicle-related proteins, such as VAMP (synaptobrevin), syntaxin-1, synaptophysin, synapsin Ia/b and IIa, munc-18, and Rab3A in the ventral hippocampus of PRS rats. Anxiety-like behavior in male PRS (and control) rats was inversely related to the extent of depolarization-evoked glutamate release in the ventral hippocampus. A causal relationship between anxiety-like behavior and reduction in glutamate release was demonstrated usingamixtureofthemGlu2/3 receptor antagonist, LY341495, and the GABAB receptor antagonist, CGP52432, which was shown to amplify depolarization-evoked 3HD-aspartate release in the ventral hippocampus. Bilateral micro infusion of CGP52432 plus LY341495 in the ventral hippocampus abolished anxiety-like behavior in PRS rats. These findings indicate that an impairment of glutamate release in the ventral hippocampus is a key component of the neuro plastic program induced by PRS, and that strategies aimed at enhancing glutamate release in the ventral hippocampus correct the "anxious phenotype" caused by early life stress
Deep learning model for automatic prostate segmentation on bicentric T2w images with and without endorectal coil
Automatic segmentation of the prostate on Magnetic Resonance Imaging (MRI) is one of the topics on which research has focused in recent years as it is a fundamental first step in the building process of a Computer aided diagnosis (CAD) system for cancer detection. Unfortunately, MRI acquired in different centers with different scanners leads to images with different characteristics. In this work, we propose an automatic algorithm for prostate segmentation, based on a U-Net applying transfer learning method in a bi-center setting. First, T2w images with and without endorectal coil from 80 patients acquired at Center A were used as training set and internal validation set. Then, T2w images without endorectal coil from 20 patients acquired at Center B were used as external validation. The reference standard for this study was manual segmentation of the prostate gland performed by an expert operator. The results showed a Dice similarity coefficient >85% in both internal and external validation datasets.Clinical Relevance- This segmentation algorithm could be integrated into a CAD system to optimize computational effort in prostate cancer detection
- âŠ