► Synthetic cathinones are a new class of designer drugs of abuse. ► These substances are marketed as “bath salts” or “plant food”. ► Cathinone derivatives are used as alternative to other illicit ...stimulants. ► Synthetic cathinones can produce neurological and cardiovascular toxicity. ► Literature data suggest a high risk of acute toxicity, tolerance and dependence.
In 2000s, many synthetic cathinones have received a renewed popularity as designer drugs of abuse, particularly among young people. Despite being marketed as “bath salts” or “plant food” and labeled “not for human consumption”, people utilize these substances for their amphetamine or cocaine like effects. Since the time of their appearance in the recreational drug market, in several countries have been signaled numerous confirmed cases of abuse, dependence, severe intoxication and deaths related to the consumption of synthetic cathinones. The aim of this paper is to summarize the clinical, pharmacological and toxicological information about this new class of designer drugs of abuse.
Intelligent systems in nature like the mammalian nervous system benefit from adaptable inputs that can tailor response profiles to their environment that varies in time and space. Study of such ...plasticity, in all its manifestations, forms a pillar of classical and modern neuroscience. This study is concerned with a novel form of plasticity in the olfactory system referred to as induction. In this process, subjects unable to smell a particular odor, or unable to differentiate similar odors, gain these abilities through mere exposure to the odor(s) over time without the need for attention or feedback (reward or punishment). However, few studies of induction have rigorously documented changes in olfactory threshold for the odor(s) used for "enrichment." We trained 36 CD-1 mice in an operant-olfactometer (go/no go task) to discriminate a mixture of stereoisomers from a lone stereoisomer using two enantiomeric pairs: limonene and carvone. We also measured each subject's ability to detect one of the stereoisomers of each odor. In order to assess the effect of odor enrichment on enantiomer discrimination and detection, mice were exposed to both stereoisomers of limonene or carvone for 2 to 12 weeks. Enrichment was effected by adulterating a subject's food (passive enrichment) with one pair of enantiomers or by exposing a subject to the enantiomers in daily operant discrimination testing (active enrichment). We found that neither form of enrichment altered discrimination nor detection. And this result pertained using either within-subject or between-subject experimental designs. Unexpectedly, our threshold measurements were among the lowest ever recorded for any species, which we attributed to the relatively greater amount of practice (task replication) we allowed our mice compared to other reports. Interestingly, discrimination thresholds were no greater (limonene) or only modestly greater (carvone) from detection thresholds suggesting chiral-specific olfactory receptors determine thresholds for these compounds. The super-sensitivity of mice, shown in this study, to the limonene and carvone enantiomers, compared to the much lesser acuity of humans for these compounds, reported elsewhere, may resolve the mystery of why the former group with four-fold more olfactory receptors have tended, in previous studies, to have similar thresholds to the latter group. Finally, our results are consistent with the conclusion that supervised-perceptual learning i.e. that involving repeated feedback for correct and incorrect decisions, rather than induction, is the form of plasticity that allows animals to fully realize the capabilities of their olfactory system.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
► 3,4-Methylenedioxypyrovalerone (MDPV) is a new designer drug of abuse. ► This substance is marketed as bath salts. ► MDPV is used as alternative to other illicit stimulants. ► MDPV can produce ...neurological and cardiovascular toxicity. ► Literature data suggest a high risk of acute toxicity, tolerance and dependence.
The illicit marketplace of substances of abuse continually offers for sale legal alternatives to controlled drugs to a large public. In recent years, a new group of designer drugs, the synthetic cathinones, has emerged as a new trend, particularly among young people. The 3,4-methylenedioxypyrovalerone (MDPV), one of this synthetic compounds, caused an international alert for its cardiovascular and neurological toxicity. This substance, sold as bath salts, has caused many serious intoxications and some deaths in several countries. The aim of this paper is summarise the clinical, pharmacological and toxicological information about this new designer drug.
The behavior of charged pion masses in the presence of a static uniform magnetic field is studied in the framework of the two-flavor NJL model, using a magnetic field-independent regularization ...scheme. Analytical calculations are carried out employing the Ritus eigenfunction method, which allows us to properly take into account the presence of Schwinger phases in the quark propagators. Numerical results are obtained for definite model parameters, comparing the predictions of the model with present lattice QCD results.
In the framework of the Nambu–Jona-Lasino (NJL) model, we study the effect of an intense external uniform magnetic field on neutral and charged pion masses and decay form factors. In particular, the ...treatment of charged pions is carried out on the basis of the Ritus eigenfunction approach to magnetized relativistic systems. Our analysis shows that in the presence of the magnetic field three and four nonvanishing pion-to-vacuum hadronic form factors can be obtained for the case of the neutral and charged pions, respectively. As expected, it is seen that for nonzero magnetic field the π0 meson can still be treated as a pseudo Nambu-Goldstone boson, and consequently the corresponding form factors are shown to satisfy various chiral relations. For definite parametrizations of the model, numerical results for π0 and π± masses and decay constants are obtained and compared with previous calculations given in the literature.
•Evaporative pads applied to gas cooler are very effective to reduce energy use.•Subcooling by chilled water from HVAC is as effective as parallel compression.•Evaporative gas coolers are a promising ...solution also in hot and humid climates.
Subcooling methods at the exit of the gas cooler in transcritical CO2 commercial refrigeration systems have been studied in the recent years showing that overall remarkable improvements can be obtained. Another strategy that results efficient is the use of evaporative systems at the gas cooler (adiabatic cooling) as it allows to significantly reduce the refrigerant quality at the liquid receiver and to lower the heat rejection pressure. In this work, a fully instrumented CO2 transcritical booster system with parallel compression, in operation in a small size supermarket in northern Italy, made available measured data of its performance when subcooling and/or adiabatic cooling are active. The plant operates in a mild climate, where it suffers operation at transcritical conditions for most of the year. Subcooling in this plant is performed by coupling the refrigeration system with the HVAC system. Taking advantage of experimental measurements, a model in the TRNSYS environment is validated and allows the prediction of the annual plant performance when these strategies are adopted. The adiabatic cooling showed to allow a significant reduction (about 10%) in the energy use, and makes unnecessary the use of a parallel compressor. Subcooling by the HVAC gives rise to a reduced saving (2.9%) due to the absence of a dedicated mechanical subcooler, however it is almost comparable to parallel compression. These trends are confirmed in two other hot and humid climates.
•Dual-stage power inverter is used for grid-tied PV application.•MPPT approach is based on the extremum seeking scheme.•Fast tracking of the irradiation changes is performed by an adaptive sliding ...surface.•Sliding mode control achieves voltage load balance and power factor correction.•Numerical results show good performance in terms of power efficiency and quality.
In this paper the design and the control of an advanced PV (Photovoltaic) inverter is discussed. The input power stage consists of a dc–dc converter based on coupled-inductors boost topology. This circuital configuration guarantees the high voltage amplification needed in grid-connected PV applications. The second power stage is a three-phase inverter operated in order to exploit the functionality of a two legs configuration. The operation principle of the proposed circuit is analyzed and a proper PV panel model is used. The adopted control strategy is based upon sliding control technique in order to exploit its well-known properties of robustness. Furthermore, a Maximum Power Point Tracking (MPPT) approach based on the extremum seeking scheme has been employed for fast tracking the irradiation changes by performing an adaptive sliding surface. Moreover, a great attention has been devoted to the control of the inverter in order to obtain power factor correction, effective reduction of both unbalances and waveforms distortion. Finally, the numerical results reported in the paper permit to confirm the feasibility of the proposed design and control strategy.
We discuss the possibility of defining an emergent local temperature in extended quantum many-body systems evolving out of equilibrium. For the most simple case of free-fermionic systems, we give an ...explicit formula for the effective temperature in the case of, not necessarily unitary, Gaussian preserving dynamics. In this framework, we consider the hopping fermions on a one-dimensional lattice submitted to randomly distributed projective measurements of the local occupation numbers. We show from the average over many quantum trajectories that the effective temperature relaxes exponentially towards infinity.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The brain's visual cortex processes information concerning form, pattern, and motion within functional maps that reflect the layout of neuronal circuits. We analyzed functional maps of orientation ...preference in ferret, tree shrew, and galago--three species separated since the basal radiation of placental mammals more than 65 million years ago--and found a common organizing principle. A symmetry-based class of models for the self-organization of cortical networks predicts all essential features of the layout of these neuronal circuits, but only if suppressive long-range interactions dominate development. We show mathematically that orientation-selective long-range connectivity can mediate the required interactions. Our results suggest that self-organization has canalized the evolution of the neuronal circuitry underlying orientation preference maps into a single common design.
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