Dimethyltyrosine, the Viagra of Opioids

Introduction Theintroductionof2′,6′dimethyl L tyrosine(Dmt)[1]attheN terminusofTyr Tic(1,2,3,4tetra hydroisoquinoline3carboxylicacid)containingδopi oidantagonists[2—8]enhancesreceptoraffinityand invitrobioactivitytoseveralordersofmagnitude[1]and itsap…     

Performances of a TRACERlab FX C synthesis module using a Ni-nanopowder/molecular sieves mixed catalyst

The progress of positron emission tomography goes together with an increasing demand for new radiopharmaceuticals: among these, the development of radiopharmaceuticals labelled with carbon-11 is particularly interesting because these compounds are biologically indistinguishable from their stable analogues. These radiotracers are prepared starting from [¹¹C]carbon dioxide, the most common and versatile primary labelling precursor, or from secondary labelling precursors such [¹¹C]methyl iodide produced by “wet” or “gas-phase” method. The gas-phase is the most used method and consists in the radical reaction of iodine vapours with [¹¹C]methane, produced in target or from [¹¹C]carbon dioxide by reduction with hydrogen on nickel catalyst at high temperature. This second approach is frequently adopted in commercial automatic methylation modules, such as the TRACERlab FX C. When not performed in target, [¹¹C]CH₄ production represents a key step for the [¹¹C]CH₃I synthesis from which the outcome of the whole radiolabelling process depends. In order to improve the performance of the module, a new reduction catalyst made of a mixture of metallic Ni (nanopowder) and molecular sieves mixed in different ratios has been tested. Preliminary results demonstrated that not only the mixture of nanopowder-Ni and molecular sieves represents a valid reduction catalyst but also permits to trap [¹¹C]CO₂ and subsequently use it as labelling reagent, making TRACERlab FX C a module for both methylation and carboxylation.     

Mucuna pruriens Administration Minimizes Neuroinflammation and Shows Anxiolytic,Antidepressant and Slimming Effects in Obese Rats

This study evaluated the effect of Mucuna pruriens (MP) administration on neuroinflammation and behavioral and murinometric parameters in obese rats. Proximate composition, oligosaccharide and phenolic compound profile of MP were determined. Wistar adult male rats were randomized into healthy (HG) and obese group (OG). The HG consumed a control chow diet while OG consumed a cafeteria diet for eight weeks. Then, they were subdivided into: Healthy (HG); Healthy with MP administration (HGMP); Obese (OG); Obese with MP administration (OGMP), with the consumption of the respective diets remaining for another eight weeks, in addition to gavage with MP extract to supplemented groups (750 mg/kg weight). MP presented a composition rich in proteins and phenolic compounds, especially catechin, in addition to 1-kestose and levodopa. Supplementation reduced food intake, body weight, and thoracic and abdominal circumferences in obese rats. MP showed anxiolytic and antidepressant effects and reduced morphological damage and expression of interleukin 6 in the hippocampus of obese rats. MP treatment showed satietogenic, slimming, anxiolytic and antidepressant effects, besides to minimizing hippocampal neuroinflammation in obese rats. Our results demonstrated the potential anti-obesity of MP which are probably related to the high content of bioactive compounds present in this plant extract.     

Universal multifractal approach to intermittency in high energy physics

A new stochastic approach to intermittency in high energy physics is proposed. It yields to intermittency exponents defined independently of phase-space dimensions; their role in the calculation of generalized moments is discussed. A straightforward application of universal multifractals is suggested and a new parametric technique for phase-space analysis is provided.     

Singlet-Triplet Energy Inversion in Carbon Nitride Photocatalysts

Time-resolved EPR (TR-EPR) demonstrates the formation of well-defined spin triplet excitons in carbon nitride. This permits to experimentally probe the extent of the triplet wavefunction which delocalizes over several tri-s-triazine units. Analysis of the temperature dependence of the TR-EPR signal reveals the mobility of the triplet excitons. By employing monochromatic light excitation in the range 430–600 nm, the energy of the spin triplet is estimated to be ≈0.2 eV above the conduction band edge, proving that the triplet exciton lies above the corresponding singlet. Comparison between amorphous and graphitic forms establishes the singlet-triplet inversion as a general feature of carbon nitride materials.     

Weight function theory and variational formulations for three-dimensional plane elastic cracks advancing

The weight function theory for three-dimensional elastic crack analysis received great attention after the work of Rice (1985, 1989). Several applications have been considered since then, particularly in the context of configurational stability, crack path prediction, stress intensity factor expansions, perturbation approaches. In all cases, a specific hypothesis has been made on the variation of crack shape, in order to formulate the problem in terms of Cauchy principal value. In the present note, such hypothesis is further investigated and consequences discussed. A variational statement given in Salvadori and Fantoni (2013a) is thus rephrased in terms of weight functions. Its discrete formulation shows the potential to accurate approximation of crack front propagation.     

Transient analysis of boiling heat transfer in periodic drying out miniature pools

The evolution of the two-phase thermal control technique is moving in the direction of the use of devices which operate in stable periodic or chaotic unsteady regimes. In these devices the heat transfer coefficient relative to the evaporator walls therefore changes over time and it is hardly predictable, especially in the case of boiling regime. This paper deals with the analysis of the boiling coefficient evolutions over time during the operations of a thermal control devices which periodically operates, the Periodic Two-Phase Thermosyphon (PTPT). An experimental technique for measuring the transient boiling heat transfer coefficient in a thick flat evaporator is shown.