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Four samples of patients (fulfilling at the index episode, respectively, Research Diagnostic Criteria for schizoaffective disorder manic type, schizoaffective disorder depressed type, manic disorder and major depressive disorder) were followed up for 3 years. At the end of the follow-up period, no significant difference with respect to the mean scores on the Disability Assessment Schedule (DAS) and on the Strauss-Carpenter Outcome Scale was observed between schizomanics and manics (although the global outcome was slightly poorer in the former group). In contrast, significant differences between schizodepressives and depressives were found both on some DAS subscales (the schizodepressives were more socially withdrawn, had less social contacts and poorer work performance) and on the Strauss-Carpenter Outcome Scale (the mean total score and the mean scores on the items "social contacts" and "employment" were significantly lower in schizodepressives). The most frequent pattern of course in patients diagnosed cross-sectionally as schizomanic was a bipolar one. Some patients had only recurrent schizomanic episodes and others more an alternance of schizomanic and schizophrenic episodes. In patients diagnosed cross-sectionally as schizodepressives, the most frequent pattern of course was that characterized by recurrent schizodepressive episodes. In some patients an alternance of schizodepressive and depressive or schizodepressive and schizophrenic episodes was observed. These data confirm that patients diagnosed cross-sectionally as schizoaffective represent a very heterogeneous group when they are studied longitudinally, and support the usefulness of a "multiaxial" approach to the classification of schizoaffective disorders, taking into account both cross-sectional symptomatology and clinical course.

A case is presented of Dejerine-Sottas disease in a 12-year-old boy in which clinical signs made diagnosis of Friedreich's ataxia seem plausible. Based on marked slowing of motor conduction velocity, the sural nerve biopsy findings of a hypertrophic neuropathy with hypo- and demyelination of the nerve fibres, as well as the clinical history, the diagnosis of Dejerine-Sottas disease was made. ABR examination suggested involvement of brain stem at the roots and/or nuclei of the eighth cranial nerve, without involvement of higher structures.

Re-ignition of aeroengines under high altitude conditions is of great importance to the safety and use of lean-burn flame. This study is focused on the experimental and numerical characterization of flow dynamics and flame re-ignition in a rectangular burner. A ring-needle type plasma actuator was considered and run by high-voltage (HV) nanopulsed plasma generator. The electrical power delivered to the fluid and an optimal value of reduced electric field (EN) was calculated considering non-reactive flow. Smoke flow visualizations using a high-speed camera and proper orthogonal decomposition (POD) were performed to recognize the most dominant flow structures. Experimental results revealed the transport effects due to plasma discharge, such as the induced flow, that could have a strong impact on the recirculation zone near the corners of combustor, improving the mixing performance and reducing the ignition delay time. Two different numerical tools (ZDPlasKin and Chemkin) were used to investigate the ignition characteristics. ZDPlasKin calculated the thermal effect and the plasma kinetic of nanopulsed plasma discharge at the experimentally measured EN. Finally, based on the output of ZDPlasKin, Chemkin estimated the flame ignition at low pressure and low temperature conditions. It was noticed that time required to achieve the maximum flame temperature with plasma actuation is significantly less than the auto-ignition time (‘clean case’, simulation result of the model without considering the plasma effect). Maximum reduction in ignition time was observed at inlet pressure 1 bar (3.5 × 10−5s) with respect to the clean case (1.1 × 10−3s). However, as the inlet pressure is reduced, the ignition delay time was increased. At 0.6 bar flame ignition occurred in clean case at 0.0048 s and at 0.0022 s in presence of the plasma actuation, a further decrease of the pressure up to 0.4 bar leads the ignition at 0.0027 s and 0.0063 s in clean and plasma actuation, respectively.

These days, various national and international research organizations are working on the development of low NOx combustors. The present work describes the experimental and numerical characterization of flow dynamics and combustion characteristics in a rectangular burner. A ring-needle type plasma actuator was developed and driven by a high voltage nanosecond pulsed generator under atmospheric conditions. Smoke flow visualizations and Proper Orthogonal Decomposition (POD) were carried out to identify the relevant flow structures. Electrical characterization of the non-reactive flow was carried out to predict the electrical power and the optimum value of the reduced electric field (EN), which is useful for the implementation of a numerical model for the study of plasma-assisted ignition. A detailed plasma kinetic mechanism integrated with all excited species was considered and validated with experimental studies. Numerical modeling of plasma ignition has been performed by coupling ZDPlasKin with CHEMKIN. Energy and power consumption for methane/air plasma actuation is higher than the air plasma actuation. This could be due to the excitation and ionization of methane that required more energy deposition and power. The mole fraction of O atoms and ozone was higher in the air than the methane/air actuation. However, O atoms were produced in a very short time interval of 10−7 to 10−6 s, in contrast, the concentration of ozone was gradually increased with the time interval and the peak was observed around 10−1 s. Plasma discharges on the methane/air mixture also produced radicals that played a key role to enhance the combustion process. It was noticed that the concentration of H species was high among all radicals with a concentration of nearly 10−1. The concentration peak of CH3 and OH was almost the same in the order of 10−2. Finally, the mixture ignition characteristics under different low inlet temperatures were analyzed for both air and methane/air plasma actuation in the presence of different plasma discharges pulses numbers. Results showed that it is possible to reach flame ignition at inlet temperature lower than the minimum required in the absence of plasma actuation, which means ignition is possible in cold flow, which could be essential to address the re-ignition problems of aeroengines at high altitudes. At Ti = 700 K, the ignition was reached only with plasma discharges, ignition time was in the order of 0.01 s for plasma discharges on methane/air, lower than in case of plasma in air, which permitted ignition at 0.018 s. Besides this, in the methane/air case, 12 pulses were required to achieve successful ignition, however, in air, 19 pulses were needed to ignite.

Greenhouse crops represent a significant productive sector of the agricultural system, one of the main problems to be addressed is indoor air conditioning to ensure thermal well-being of crops. This study focuses on the ventilation analysis of solar greenhouse with symmetrical flat pitched roof and single span located in a warm temperate climate. This work proposes the dynamic analysis of the greenhouse modeled in TRNsys, simultaneously considering different thermal phenomena three-dimensional (3D) shortwave and longwave radiative exchange, airflow exchanges, presence of lamps with their exact 3D position, ground and plant evapotranspiration, and convective heat transfer coefficients. Several air conditioning systems were analyzed, automatic window opening, controlled mechanical ventilation systems (CMV) and horizontal Earth-to-Air Heat Exchanger (EAHX) coupled with CMV, for different air volume changes per hour. In summer, the exploitation of the ground allows having excellent results with the EAHX system, reducing the temperature peaks of up to 5 &deg, C compared to the use of CMV. In winter, it is interesting to note that, although the EAHX is not the solution that raises the temperature the most during the day, its use allows flattening the thermal wave more. In fact, the trend is almost constant during the day, raising the temperature during the first and last hours of the day.

Geothermal energy has a huge potential in building applications. This paper proposes the use of an Air-Source Heat Pump (ASHP) system coupled with a Horizontal Earth-To-Air Heat Exchanger (EAHX) to reduce energy consumption in buildings. The novelty is to geothermally pre-heat or pre-cool the air source of the ASHP through the EAHX, reducing the electric power needed, keeping constant heating/cooling capacity. The behaviour of ASHP-EAHX system has been investigated by a numerical model implemented in TRNSYS. A total of 54 combinations have been obtained and tested varying ground thermal properties, burial depth, air flow rate and pipe length. The model has been validated with a real case showing a good agreement between simulated and monitored data. The study is focused on the city of Turin (North of Italy), compared with Brindisi (South of Italy), and extremely cold and hot climates like Tromso (Norway) and Bechar (Algeria), respectively. The ASHP-EAXH performance has been investigated, by the comparison with the traditional ASHP, using different coefficients, such as the Coefficient of Performance (COP), the Energy Efficiency Ratio (EER), the Seasonal Coefficient of Performance (SCOP), and the Seasonal Energy Efficiency Ratio (SEER). The paper reveals how the ASHP-EAHX system show higher performance compared to the traditional ASHP, in all seasons. The overall merit is, for cold extremely climate, the reduction of the shutdown periods, when the outside temperature is below the limit operating temperature, and to allow the extension of the use of the heat pump to locations, where it is currently not convenient for the average outside temperature lower than the limit operating temperature of the heat pump.

Objective.—The study explored the hypothesis that spontaneous nystagmus (Ny) in migraine patients can be triggered or modulated by painful trigeminal stimulation, providing evidence of a functional connection between vestibular and trigeminal systems. Background.—Vertigo attacks are reported by subjects with migraine or a familiar history of migraine, also independently of headache episodes. Idiopathic vertigo is three times more frequent in migraine patients than in controls. Vestibular investigations in migraine patients have consistently demonstrated spontaneous Ny both of central and peripheral origin. Design.—In the first phase of the study 10 outpatients experiencing migraine without aura (MO) and 10 healthy volunteers were submitted to the registration of spontaneous primary-position Ny in the dark by Ulmer's video-ocular-nystagmographic equipment. Two electrodes for electrical stimulation were applied on the supraorbital point of one side of the head and the intensity of stimulation corresponding to pain threshold was calculated. Spontaneous ocular movements were recorded for 5 minutes at baseline and after a sequence of five electric pulses (square waves of .5 Hz frequency and 50 μs duration, at pain threshold intensity). Nystagmographic responses were expressed as latency after stimulation, direction of the quick phase, and duration. The second phase of the study explored, with the same procedure, the effects on Ny of supraorbital versus median nerve stimulation in other 10 MO patients. Responses to stimulation were considered the appearance of de novo Ny after stimulation in subjects without baseline Ny, or the change of the frequency (at last a 50% variation) or of the direction of Ny after stimulation in subjects with baseline Ny. The latency and the duration of responses to stimulation were also calculated. Results.—In the first series supraorbital painful electric stimulation was able to modify or to evoke Ny in 8 of 10 migraineurs and in none of 10 volunteers (Fisher's exact test, P < .01). Both the baseline and the induced Ny were second degree, stationary persistent, with a linear slow phase and were suppressed by visual fixation. In the second series, supraorbital nerve stimulation was able to induce or modify Ny in all of 10 patients but only in 1 patient Ny was induced by median nerve stimulation. Characters of Ny were the same as previously described. Statistical comparison of the responses at the two sites of stimulation was significant (Fisher's exact test, P < .01). In those 7 patients who presented de novo Ny after stimulation it was possible to calculate Ny latency and duration. The mean latency was 25 s (SD: 16, range: 14 to 60). The mean duration was 120 s (SD: 94, range: 20 to 290). Conclusion.—The main result of our study is that in migraine patients painful trigeminal stimulation elicits de novo, or modifies pre-existing spontaneous Ny, generally increasing it. The finding was obtained after trigeminal stimulation, but not after median nerve stimulation. We suggest that painful trigeminal stimulation can induce an imbalance of the vestibular system in migraine patients and possibly explain their predisposition to vertigo. Our data require confirmation by other studies.