The Classical Analogue of CP-violation

The phenomenological features of the mixing in the neutral pseudoscalar mesons K0-K0bar can be illustrated in the classical framework of mechanics and by means of electromagnetic coupled circuits. The time-reversed not-invariant processes and the related phenomenon of CP-nonconservation can be induced by dissipative effects which yield a not vanishing imaginary part for the relevant Hamiltonian. Thus, two coupled dissipative oscillators can resemble the peculiar asymmetries which are so common in the realm of high energy particle physics.Comment: 12 pages, Latex, 2 figures available by fa

The WKB Approximation without Divergences

In this paper, the WKB approximation to the scattering problem is developed without the divergences which usually appear at the classical turning points. A detailed procedure of complexification is shown to generate results identical to the usual WKB prescription but without the cumbersome connection formulas.Comment: 13 pages, TeX file, to appear in Int. J. Theor. Phy

Involvement of Norepinephrine in the Control of Activity and Attentive Processes in Animal Models of Attention Deficit Hyperactivity Disorder

Functional and morphological studies in children affected by Attention Deficit Hyperactivity Disorder (ADHD) suggest a prefrontal cortex (PFc) dysfunction. This cortical region is regulated by subcortical systems including noradrenergic (NEergic), dopaminergic (DAergic), cholinergic, serotonergic, and histaminergic pathways. A wealth of data in humans and in animal models demonstrates altered dopamine (DA) regulation. Drugs that modulate norepinephrine (NE) transmission are also effective in ADHD patients, thus leading to the hypothesis of a NEergic disorder. This review covers the regulation of PFc functions by NE and the interaction between the NE and DA systems, as suggested by pharmacological, electrophysiological, morphological, and gene knock out (KO) studies. A negative feedback between NE and DA neurons emerges from KO studies because KO mice showing increased (NE transporter (NET) KO) or decreased (DBH and VMAT2 KO) NE levels are respectively associated with lower and higher DA levels. Locomotor activity can be generally predicted by the DA level, whereas sensitivity to amphetamines is by NE/DA balance. Some animal models of ADHD, such as spontaneously hypertensive rats (SHR), show alterations in the PFc and in the DA system. Evidence about a correlation between the NE system and hyper-locomotion activity in such animals has not yet been clarified. Therefore, this review also includes recent evidence on the behavioral effects of two NET blockers, reboxetine and atomoxetine, in two animal models of ADHD: SHR and Naples High Excitability rats. As these drugs modulate the DA level in the PFc, certain effects are likely to be due to a rebalanced DA system. We discuss the significance of the results for theories of ADHD and make suggestions for future experimentation

Isolation of intermediate compounds between hemoglobin and carbon monoxide.

A human hemoglobin solution partially saturated with carbon monoxide was rapidly quenched at -25 degrees C into a hydro-organic buffer containing ferricyanide. Under the experimental conditions of pH, ionic strength, and buffer composition used in this work, it was found that the deoxy hemes were rapidly transformed into their met form, whereas practically no carbon monoxide-bound hemes were oxidized before the separation of the mixture from the oxidizing agent. As a preliminary step to the analysis of the resulting solution, carbonylhemoglobin solutions partially oxidized with ferricyanide were studied by isoelectric focusing at -25 degrees C under identical conditions. The relative position in the gel of all nine possible valence hybrids was established as follows (going from the anodic to the cathodic side of the gel) alpha CO2 beta CO2, (alpha CO beta +)(alpha CO beta CO) (alpha CO beta CO), (alpha CO2 beta +2), (alpha + beta CO), (alpha + beta +)-(alpha CO beta CO), (alpha + beta +)(alpha CO beta +), (alpha +2 beta CO2), (alpha + beta +)(alpha + beta CO), alpha +2 beta +2. When carbonylhemoglobin and methemoglobin were mixed in equal proportion at -25 degrees C and then analyzed by isoelectric focusing at the same temperature, it was found that the contribution of valence hybrids other than alpha CO2 beta CO2 and alpha +2 beta +2 to the total amount of hemoglobin in the gel was no more than 6%. When carbonylhemoglobin and deoxyhemoglobin were mixed in the same proportion and incubated at 20 degrees C so to allow the redistribution of the carbon monoxide molecules between all possible binding sites to occur, a substantially higher amount of valence hybrids, derived from the oxidation of intermediate compounds of hemoglobin with carbon monoxide, was found. The isoelectric focusing separation indicated the presence in the original solution of intermediate species other than carbonylhemoglobin and deoxyhemoglobin at a concentration of about 10% of the total

Secure ADS-B authentication system and method

A secure system for authenticating the identity of ADS-B systems, including: an authenticator, including a unique id generator and a transmitter transmitting the unique id to one or more ADS-B transmitters; one or more ADS-B transmitters, including a receiver receiving the unique id, one or more secure processing stages merging the unique id with the ADS-B transmitter's identification, data and secret key and generating a secure code identification and a transmitter transmitting a response containing the secure code and ADSB transmitter's data to the authenticator; the authenticator including means for independently determining each ADS-B transmitter's secret key, a receiver receiving each ADS-B transmitter's response, one or more secure processing stages merging the unique id, ADS-B transmitter's identification and data and generating a secure code, and comparison processing comparing the authenticator-generated secure code and the ADS-B transmitter-generated secure code and providing an authentication signal based on the comparison result

Dopamine: The Neuromodulator of Long-Term Synaptic Plasticity, Reward and Movement Control

Dopamine (DA) is a key neurotransmitter involved in multiple physiological functions including motor control, modulation of affective and emotional states, reward mechanisms, reinforcement of behavior, and selected higher cognitive functions. Dysfunction in dopaminergic transmission is recognized as a core alteration in several devastating neurological and psychiatric disorders, including Parkinson's disease (PD), schizophrenia, bipolar disorder, attention deficit hyperactivity disorder (ADHD) and addiction. Here we will discuss the current insights on the role of DA in motor control and reward learning mechanisms and its involvement in the modulation of synaptic dynamics through different pathways. In particular, we will consider the role of DA as neuromodulator of two forms of synaptic plasticity, known as long-term potentiation (LTP) and long-term depression (LTD) in several cortical and subcortical areas. Finally, we will delineate how the effect of DA on dendritic spines places this molecule at the interface between the motor and the cognitive systems. Specifically, we will be focusing on PD, vascular dementia, and schizophrenia

Sustainability in automotive transport: Russian and Italian experience concerning actual situation and intervention tools

The air quality in metropolitan areas of Russia and Italy, although with different distribution and intensity, raises similar concerns for the respective public authorities about vehicle emissions, as well as about the stagnation of toxic pollutants in urban areas. This article discusses some typical situations in both these countries. In order to obtain suitable solutions to diminish this form of impact, different tools that are based on different approaches can be proposed. It is necessary to consider both the practical possibility of application and the cost-benefit balance that takes into account the realization cost and industrial system transformation on one side, and the results in terms of air quality improvement on the other. The different instruments (technological intervention on engines, chemical modification of fuels, mobility and road infrastructural planning) are presented for the considered countries, and also in more developed European and American areas, with a concentrated interest in areas of applicability, costs and obtained results. The externality of this form of pollution is presented and discussed, and the aspect of limitation of impact and consequent external costs is evaluated in comparison with monetary and infrastructural costs for emissive system modification. © 2016 WIT Press, www.witpress.com

In Vivo Mapping of the Choriocapillaris in High myopia: a Widefield Swept Source Optical Coherence Tomography Angiography

To report variation of choriocapillaris (CC) flow in widefield in high in myopic subjects compared with an age-matched normal control group using ultra widefield optical coherence tomography angiography (UW-OCTA). This is a Prospective, cross-sectional study. Thirty high myopia subjects and fifty healthy subjects were enrolled. Healthy and high myopia subjects were imaged with the SS-OCTA system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). For each eye, five 12 × 12-mm OCTA volume scans were acquired. The en face CC images were then exported to imageJ and a semi-automated algorithm was used for subsequent quantitative analysis. The main outcome was a quantitative analysis of the CC. This analysis was performed in three different regions: (i) peripapillary, (ii) macular, and (iii) periphery. In addition, CC variables were further investigated in distinct fields within these three different regions. Thirty myopic eyes (32 subjects; myopic group) and fifty eyes (50 subjects; control group) without elevated myopia were included in the analysis. Mean ± SD age was 26.9 ± 2.9 years [median: 27 years; range: 20.0–40.0 years]. Mean ± SD axial length was 26.6 ± 0.6 mm [median: 26.2 mm; range: 26.1 to 28.0 mm]. Mean ± SD axial length was 26.6 ± 0.6 mm [median: 26.2 mm; range: 26.1 to 28.0 mm] in the myopic group and 23.9 ± 1.1 mm [median: 23.9 mm; range: 21.8 to 25.9 mm] in the control group. The total signal void area was significantly greater in myopic eyes compared with control group. The peripapillary region exhibited the greatest total signal void area (p < 0.0001 vs macular region, p < 0.0001 vs peripheral region). Within the macular region, the foveal area exhibited a greater total signal void area in comparison with both the parafoveal area (p < 0.0001) and the perifoveal area (p < 0.0001). In conclusion we report quantitative mapping of the choriocapillaris in myopic eyes compared with an age-matched normal control group. The CC perfusion appears to have a wide topographical variation