88 research outputs found
Acute Ketamine Facilitates Fear Memory Extinction in a Rat Model of PTSD Along With Restoring Glutamatergic Alterations and Dendritic Atrophy in the Prefrontal Cortex
Stress represents a major risk factor for psychiatric disorders, including post-traumatic stress disorder (PTSD). Recently, we dissected the destabilizing effects of acute stress on the excitatory glutamate system in the prefrontal cortex (PFC). Here, we assessed the effects of single subanesthetic administration of ketamine (10 mg/kg) on glutamate transmission and dendritic arborization in the PFC of footshock (FS)-stressed rats, along with changes in depressive, anxious, and fear extinction behaviors. We found that ketamine, while inducing a mild increase of glutamate release in the PFC of na\uefve rats, blocked the acute stress-induced enhancement of glutamate release when administered 24 or 72 h before or 6 h after FS. Accordingly, the treatment with ketamine 6 h after FS also reduced the stress-dependent increase of spontaneous excitatory postsynaptic current (sEPSC) amplitude in prelimbic (PL)-PFC. At the same time, ketamine injection 6 h after FS was found to rescue apical dendritic retraction of pyramidal neurons induced by acute stress in PL-PFC and facilitated contextual fear extinction. These results show rapid effects of ketamine in animals subjected to acute FS, in line with previous studies suggesting a therapeutic action of the drug in PTSD models. Our data are consistent with a mechanism of ketamine involving re-establishment of synaptic homeostasis, through restoration of glutamate release, and structural remodeling of dendrites
Criminalidade organizada nas prisÔes e os ataques do PCC
The advent of organized crime in Brazilian prisons, especially in the state of SĂŁo Paulo, constitutes the object of this article. The waves of attack unleashed by the Capital's First Command (PCC - Primeiro Comando da Capital), in May 2006, which resulted in countless deaths, brought cities to a halt, and cornered authorities in charge preventing them from applying law and order are the starting as well as reference points taken. The advent of organized criminality is analyzed under the light of determined axes: the international scenario and the Brazilian context, the historical antecedents, the taking root of crime in society and the role of penitentiary public policies.A emergĂȘncia da criminalidade organizada nas prisĂ”es brasileiras, em especial no Estado de SĂŁo Paulo, constitui objeto deste artigo. Tomam-se como ponto de partida e referĂȘncia para anĂĄlise as ondas de ataques desencadeadas pelo Primeiro Comando da Capital (PCC), de maio a agosto de 2006, que resultaram em inĂșmeros mortos, paralisaram cidades e acuaram as autoridades encarregadas de aplicar lei e ordem. A emergĂȘncia da criminalidade organizada Ă© analisada sob eixos determinados: cenĂĄrio internacional e contexto brasileiro, antecedentes histĂłricos, enraizamento do crime na sociedade e papel das polĂticas pĂșblicas penitenciĂĄrias
Reflections on the entrepreneurial state, innovation and social justice
The state and its role in technological innovation and social justice have become, once again, fashionable topics of political and economic debate. A number of innovation theorists argue that never more than today, it is necessary to rethink the stateâs entrepreneurial role in society and welfare. Their argument provides justification for the existence of the state, going beyond classical political theory and especially contractarian accounts of legitimacy and obligation. It emphasises the ability and willingness of the state to take risks and reduce uncertainty of economic agents for the sake of innovation that can make everyone better off. This paper insists that although the risk-taking argument of innovation theorists deserves further attention and analysis, it should not be abstracted from a holistic politico-theoretical approach to the state. Such an approach is necessary for a critical understanding of the complex set of predominantly political institutions which compose the state and which have been historically developed to guarantee social evolution. Any risk-taking for innovative enterprise and mission-oriented investment ought to be justified and legitimised on the grounds of principled democratic procedures. This implies that innovation itself is a value-laden political process, requiring participation in the decision-making and standards of fairness
Micromechanical Properties of Injection-Molded StarchâWood Particle Composites
The micromechanical properties of injection molded starchâwood particle composites were investigated as a function of particle content and humidity conditions.
The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness
of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence
were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density
and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starchâwood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that
the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes
Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening
PRESSURE DEPENDENCE OF FLUORESCENCE AND PHOSPHORESCENCE
J.G. Calvert et al., J. Am. Chem. Soc. 93, 2581, 2587 (1971) and references therein.""Author Institution: Department of Chemistry and Scarborough, College University of TorontoWe have studied vibronically resolved fluorescence and phosphorescence spectra of sulfur dioxide vapor (excited by the 297 nm, 302 nm, or 313 nm lines of a mercury/xenon arc) in the pressure range of less than one millitorr to 20 millitorr. Vibrational relaxation effects appear in emission region. At the lowest pressures, emission from the singlet state can be characterized as single vibronic level fluorescence. The strong vibronic bands correspond to progressions in the totally symmetric ground state normal modes. Below 20 millitorr, the relative quantum yield of phosphorescence decreases linearly as the pressure decreases. We will discuss implications of these results with respect to current on the kinetics of electronic relaxation in vapor
THz Performance of 1550-Nm-Driven Photoconductive Switches Made From Gaas:ER With Eras Quantum Dots
Ultrafast 1550-nm extrinsic photoconductivity in GaAs:Er makes it possible to fabricate THz photoconductive devices having performance comparable to GaAs:Er devices based on traditional 780-nm intrinsic photoconductivity. This paper addresses the effect of Er doping concentration and its associated ErAs quantum-dot formation on THz device performance, focusing on photoconductive switches
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