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BackgroundAdvanced cell therapeutics are emerging as potentially effective treatments for chronic neurological diseases, including secondary progressive multiple sclerosis (SPMS). Here we report the results of a phase I trial in which good manufacturing practice-grade foetal allogeneic human neural stem cells (hNSCs) were implanted via intracerebroventricular (ICV) injection in 15 individuals with active and non-active SPMS.MethodsThis is a phase I, open-label, multicentre, dose-escalation, international study. The primary objective was to assess the feasibility, safety, and tolerability of ICV injections of allogeneic hNSCs in patients affected by SPMS over a study follow up of 12 months. We also evaluated the number and type of adverse events (AEs) leading to a maximum tolerated dose, the general health status, and mortality. The secondary objectives were the therapeutic benefit of allogeneic hNSCs using assessment scales, magnetic resonance imaging (MRI), and laboratory and neurophysiologic parameters.FindingsFifteen unrelated SPMS patients were enrolled and treated between 2018 and 2020. The participants had a median age of 49.8 years. Their mean extended disability status scale (EDSS) at enrolment was 7.6, the mean disease duration was 22 years, and mean time from diagnosis to progression was 10.1 years. Neither treatment-related deaths nor serious AEs were reported during the study (1 year follow up after treatment). All the other AEs were classified as non-serious and were associated to non-study concomitant therapy or other medical conditions not connected to the experimental treatment. During the study, none of the participants worsened in the progression of their SPMS as shown by the evaluation scales implemented to assess their progress. Laboratory and neurophysiologic parameters showed no clinically significant variations. MRI follow-up showed non-clinically significant type 1, 2, and 3 changes.InterpretationThe intracerebroventricular injection of foetal allogeneic hNSCs in people with SPMS is feasible, tolerated and safe. Study participants displayed a substantial clinical stability during the 12-month follow-up. The absence of relevant adverse reactions (Ars) arising from the transplantation of hNSCs indicates a short-term neutral balance between benefits and risks and suggests a concrete, though perspective therapeutic possibility for SPMS patients. Further studies are needed to confirm and extend the findings herein and evaluate the actual therapeutic potential of advanced cell therapeutics for a condition where the lack of effective disease modifying therapies is a major unmet clinical need.

This paper describes two small aperture array demonstrators called Medicina and Sardinia Array Demonstrators (MAD and SAD, respectively). The objectives of these instruments are to acquire experience and test new technologies for a possible application to the low-frequency aperture array of the low-frequency telescope of the Square Kilometer Array phase 1 (SKA1-LOW). The MAD experience was concluded in 2014, and it turned out to be an important test bench for implementing calibration techniques based on an artificial source mounted in an aerial vehicle. SAD is based on 128 dual-polarized Vivaldi antennas and is 1 order of magnitude larger than MAD. The architecture and the station size of SAD, which is along the construction phase, are more similar to those under evaluation for SKA1-LOW, and therefore, SAD is expected to provide useful hints for SKA1-LOW.

This paper presents the current results for the FP7 GINSEC project. Its goal is to build a pre-commercial prototype of a low-cost, accurate and reliable system for the professional UAV market. Low-cost, in this context, stands for the use of sensors in the most affordable segment of the market, especially MEMS IMUs and GNSS receivers. Reliability applies to the ability of the autopilot to cope with situations where unfavourable GNSS reception conditions or strong electromagnetic fields make the computation of the position and / or attitude of the UAV difficult. Professional and accurate mean that, at least using post-processing techniques as PPP, it will be possible to reach cm-level precisions that open the door to a range of applications demanding high levels of quality in positioning, as precision agriculture or mapping. To achieve such goal, a rigorous sensor error modelling approach, the use of redundant IMUs and a dual-GNSS receiver setup, together with close-coupling techniques and an extended Kalman filter with self-analysis capabilities have been used. Although the project is not yet complete, the results obtained up to now prove the feasibility of the aforementioned goal, especially in those aspects related to position determination. Research work is still undergoing to estimate the heading using a dual-GNNS receiver setup; preliminary results prove the validity of this approach for relatively long baselines, although positive results are expected when these are shorter than 1 m – which is a necessary requisite for small-sized UAVs.

Following the first evidence of planetary water maser emission induced by the collision of comet Shoemaker/Levy with Jupiter and the puzzling detection of the 22 GHz water emission line in Comet Hyakutake we started in the period 2002–2008 systematic observations of selected comets at 22 GHz (1.35 cm) with the aim of clarifying the unusual behavior of the maser line in the cometary “scenario”. Using a fast multichannel spectrometer coupled to the 32 m dish of the Medicina (Bologna, Italy) Radio Telescope we investigated 6 bright or sungrazing comets down to a heliocentric distance of 0.11 AU: 96P/Machholz, 153P/ Ikeya – Zhang, C/2002 V1 (NEAT), C/2002 X5 (Kudo – Fujikawa), C/2002 T7 (Linear), and 73P/Schwassmann – Wachmann 3 . All of them, similarly to Comet Hyakutake, demonstrate spectral features that, if real and due to the 1.35 cm water vapor transition, are strongly (up to tens of km/s) shifted relative to the radial velocity of the nucleus and, at least sometimes, seem to be present as two separate peaks. If our interpretation of these spectral peaks is correct, there must be some mechanism of acceleration of neutral water molecules up to the velocities of ions. We discuss here the results achieved and the possible explanation of the chemo-physical constraints.

One of the most important requirements for the astronomical Low-Frequency Aperture Arrays (LFAAs) is the high sensitivity, defined as the ratio between the effective area and the system noise temperature. This figure of merit is strictly related to the single element sensitivity, which is difficult to measure by using astronomical sources. On the other hand, the characterization of a low-frequency antenna inside an anechoic chamber is not straightforward down to 50 MHz. In this contribution a novel method to measure the sensitivity of a single LFAA receiving chain is presented. The proposed technique utilizes a micro Unmanned Aerial Vehicle equipped with a RF test source. A preliminary error budget analysis demonstrated that this technique is able to measure the sensitivity of a LFAA chain with high accuracy.

The Medicina Radioastronomical Station is located nearby Bologna, in Italy. It consists of two receiving antennas currently dedicated to the astronomical research at radio frequencies. The 32 m diameter parabolic dish performs observations from 1.4 to 22 GHz whereas the Northern Cross (a 30.000 m 2 wide T-shaped array transit antenna) works at 408 MHz. So far SETI observations have been performed using a SERENDIP IV high resolution spectrometer connected to the parabolic antenna. Data acquisition were performed meanwhile the antenna was employed in ordinary astronomical observations (piggy-back mode). An innovative method to search for possible extraterrestrial signals could be provided by using the UHF Northern Cross transit telescope. In this paper observational modalities and the required technological set-up are investigated.

An accurate measurement of the position and trajectory of the space debris fragments is of primary importance for the characterization of the orbital debris environment. The Medicina Radioastronomical Station is a radio observation facility that is here proposed as receiving part of a ground-based space surveillance system for detecting and tracking space debris at different orbital regions (from Low Earth Orbits up to Geostationary Earth Orbits). The proposed system consists of two bistatic radars formed by the existing Medicina receiving antennas coupled with appropriate transmitters. This paper focuses on the current features and future technical development of the receiving part of the observational setup. Outlines of possible transmitting systems will also be given together with the evaluation of the observation strategies achievable with the proposed facilities.

We present preliminary results for our study of mutual phenomena of the Galilean satellites performed at radio wavelengths with the Medicina and Noto antennas of the Istituto di Radioastronomia - INAF, and with the Effelsberg 100-m radio telescope of the Max-Planck-Institute for Radioastronomy, Bonn. Measurements of the radio flux density variation during the mutual occultations of Io by Europa and Ganymede were carried out during the PHEMU09 campaign at 22 GHz and 43 GHz. Flux density variations observed at radio wavelengths are consistent with the typical optical patterns measured when partial occultations occur.

Context. The presence of water has long been seen as a key condition for life in planetary environments. The Cassini spacecraft discovered water vapour in the Saturnian system by detecting absorption of UV emission from a background star. Investigating other possible manifestations of water is essential, one of which, provided physical conditions are suitable, is maser emission. Aims. We report detection of water maser emission at 22 GHz associated with several Kronian satellites using Earth-based radio telescopes. Methods. We searched for water maser emission in the Saturnian system in an observing campaign using the Metsahovi and Medicina radio telescopes. Spectral data were Doppler-corrected over orbital phase for the Saturnian satellites, yielding detections of water maser emission associated with the moons Hyperion, Titan, Enceladus, and Atlas. Results. The detection of Saturnian water molecules by remote astronomical observation can be combined with in situ spacecraft measurements to harmonise the physical model of the Saturnian system.

Nowadays, one of the major limits of Unmanned Aerial Vehicles (UAV) is the set of low cost navigator sensors installed on them. They are vulnerable to vibration, high acceleration, high rotation and jerk. Furthermore, magnetometers drift significantly when located close to engines, to electromechanical devices or in areas with strong magnetic fields (for example grid power lines). This document describes an innovative approach using multi GNSS receivers for UAV's attitude determination.

Agent-based modeling (ABM) is a powerful tool for model complex and heterogeneous systems as pedestrian evacuation after extreme events. Several studies on Emergency Management exist in literature, but the majority of them do not consider how human behavior impacts the evacuation plan. Indeed, these can change drastically a critical scenario because are driven by emotions, knowledge and perception which are unpredictable. The aim of this study is to develop an ABM of an evacuation scenario due to a blast in a public area integrated with a mathematical dynamic human behavior model. Netlogo, which is a multi-agent programmable environment, was used to build the ABM. ABMs simulate two phases: the normal phase and the agent’s evacuation process after the blast. The evacuation time is the main parameter of response and it is used to evaluate the efficiency and safety of an infrastructure. Each agent has its own behavior according to a layered framework mathematical model. The first layer, thanks to an empirical statistical distribution, simulates the “agent’s state” function of the role performed by the agent and his age. Then the” individual module” describes the emotional aspects using the Decision Field Theory. This ABM becomes an important tool that enables designers or policy makers to test, estimating and improving the response of infrastructures in hazardous scenario.

The coming space colonization will involve the possibility of establishing Space Stations (Gateways in the NASA jargon) at some Lagrangian Points in the vicinity of the Earth (5 points in the Earth-Moon system plus 2 more in the Sun-Earth system). Independently of this, the Moon Farside is the only place around the Earth that man-made radio frequency interferences (RFI) clearly cannot reach. In other words, a radio telescope or an array of antennas located in the centre of the Moon Farside would be able to achieve radio observations enormously clean and sensitive. In this paper we study the problems of radio wave diffraction that arise from the future RFI produced at the Lagrangian Points with particular regard to the frequency bands that are important in radioastronomical research. It is hoped that the future exploitation of the Moon Farside by several space-faring nations will take into account the “ecological” need to preserve at least the central part of the Moon Farside. In our understanding, this means the creation of an official RFI-Free Zone within a circle centered at crater Daedalus (i.e at around the antipode of the Earth) and extending 30 degrees in both latitude and longitude. SELECTING SOME LAGRANGIAN POINTS AS LOCATIONS FOR FUTURE SPACE BASES In a rotating two-body system five points exist in which the resulting gravity field is zero. These positions are called « libration points » or 'Lagrangian Points' after the Italian-French mathematician Joseph Louis Lagrange (17361813), who proved this result mathematically in 1772. Three of these points (L1, L2 and L3) are called ‘colinear points’ because located in the line joining the Earth and the Moon. The remaining two (L4 and L5) form two equilaterar triangles with the Earth and Moon and so are called ‘triangular points’ (see Fig. 1). NASA is currently studying the possibility of establishing future space bases at some of the libration points of the Earth-Moon system, in particular at the L1 point. In order to find out which Lagrangian point will be more suitable to host a future Space Base, it helps considering the spacecraft escape velocities from such points. In ref. [1] these escape velocities were computed by taking in account the angular velocity of the Moon around the Earth, and they turned out to be vEsc-L1-FORWARD = 0.7151198 km s vEsc-L2-FORWARD = 0.1565154 km s 2 vEsc-L3-FORWARD = 0.4094551 km s vEsc-L4-FORWARD = 0.4217945 km s where the word “forward” refers to the fact that the spacecraft is supposed to leave the relevant Lagrangian point in the direction of advancing Moon. From the above list of numbers, it plainly appears that the Earth-Moon Lagrangian point L2 would be the best solution to set up there a Space Base for which to depart for future space missions to the outer solar system, like going to Mars, Jupiter, the asteroids, and so on. However, the L2 point is located right above the Farside, at 61.347 km from the Moon center. Then, a large space station located there, would flood the Farside with its own radio noise, thus spoiling the only location free from Radio Frequency Interference (RFI) still available to humankind. In view of these problems, we shall keep L2 outside of our study, and in this paper we will consider the cases relative to the L4, L5 and L1 Lagrangian points. The L3 point remains hidden from the Moon, i.e. behind the Earth at all times. Fig. 1: The 5 Lagrangian Point of Earth-Moon system. Shown are the distances from Earth and Moon expressed in terms of Earth-Moon distance R. EXTENDING THE « QUIET CONE » CONCEPT In generic terms, the Farside of the Moon is free of man-made RFI coming from the Earth. Moreover, above the Farside itself, a conical region extends into space (called “Quiet Cone” by C. Maccone in Ref. [2]), that is tangent to the Moon surface and has its apex approximately at 16.000 km from the center of the Moon in the (important) case of RFI produced in Geostationary Earth Orbit (GEO). This region is radio-quiet because all radio waves emitted from the Earth surface, as well as by the Telecommunication Satellites orbiting around the Earth, are shielded by the Moon spherical body. The purpose of this paper is a detailed study of the RFI propagation on the Moon Farside since this would impact upon an array of radio antennas located there. This array would receive all radio signals from the Universe with an unprecedented degree of cleanliness and details. Because of this goal of ours we have to extend the “Quiet Cone” concept to all man made RFIsources and not only to the Earth-based and the telecommunication satellites put in geostationary orbit. If a source of the radio interferences is an “extended object”, such as the Earth or a satellite orbit, the Quiet Cone is well defined as shown in Fig. 2. Fig. 2: The Earth-Moon system (not to scale!). The shaded region is the “Quiet Cone” created by an extended Radio Frequency Interference source like the Earth. By definition, it is not possible to put a satellite into a circular orbit around the Earth at a distance larger than Lagrangian point L1 (located at 323.050 km). Because of this, we have to keep in into account all the “Quiet Cones” generated by: 1. Satellites orbiting the Earth at a distance smaller than the Earth-Moon Lagrangian Point L1 distance. When this distance equals L1 we obtain the worst case of RFI pollution on the Moon Farside, because the relevant Quiet Cone is the smallest possible cone. 2. Radio-quiet regions generated by the Moon shielding of RFI emissions by future SPACE stations (Gateways) located at the L4 and L5 libration points. We also have to define the “Moon Farside terminal longitude” as the highest Moon longitude at which the RFI of a certain satellite orbiting the Earth still reaches as a function of the satellite’s orbital radius around the Earth. The Moon Farside sector having a longitude higher than this angle will never be flooded by RFI coming from satellites having the corresponding 3 orbital radius. In other words, considering Fig. 3, we want to compute the “terminal longitude” λ = 180° γ. In Figure 3, let’s draw the straight line OP from the Earth center O to the satellite P. Next consider the orthogonal projection PH of point P on Earth-Moon axis OO’. This line forms a rectangular triangle having its right angle at point H. Next draw the straight line from satellite P tangent to the Moon’s sphere from H’ and intersecting the Earth-Moon axis OO’ at a certain point V (that is the Quiet Cone vertex). Finally, draw the straight line from the satellite P to the Moon center O’. Once again the triangle PHO’ is right-angled, with its right angle at a point H. Also the triangle PH’O’ is right-angled with its right angle at a point H’. Let us denote by DEarth-Moon the Earth to Moon distance and by RSat the orbital radius of satellite. Fig. 3: The satellite orbiting around the Earth determines (as function of its true anomaly θ and orbital radius R) a “terminal longitude” angle λ of the radio waves on the Moon Farside. Well, we now have what we need to find the “terminal longitude” angle λ. First let’s first find the angle γ. Since we know: 1. HPV O H V γ ′ ′ = = , HPO O PH γ γ ′ ′ ′′ ′ ′ = = γ γ γ ′ ′′ = + 2. the projection of OP on the Earth-Moon axis: OH = OP cos θ = RSat cos θ 3. the segment PH = OP sin θ = RSat sin θ 4. the segment from the satellite projection H on the Earth-Moon axis to the Moon center: HO’ = OO’ – OH = DEarth-Moon – RSat 5. the tangent of the angle γ’ is given by: ( cos ) ' tan( ) sin Earth Moon Sat Sat D R HO PH R θ γ θ − − ′ = = (1) Now inverting the equation (1) we get the γ’ angle: Sat ( cos ) (R ,θ) atan sin Earth Moon Sat

More than a million visits/year characterize acute asthma morbidity at Venezuela's (24 million inhabitants) Ministry of Health ambulatory services, caring for 80% or more of the population; acute morbidity from asthma is second to "viral syndrome" but ahead of diarrhea and other diseases. These acute episodes are the only contact of a poor asthmatic child with this health care system and portray the prevailing approach focused around acute care: to be reversed, a simple cost/effective program ought to be implemented during these acute asthma visits. Since convenience of administration is a key factor in compliance, a pilot study to explore the efficacy of budesonide CFC 400 microg administered on a once-a-day basis for adherence was carried out within a naturalistic real-world design.Thirty persistent asthmatic patients attending the Allergology Unit of the Hospital Pediátrico San Juan de Dios in Caracas were enrolled, and their asthma signs/symptoms quantified and registered on diary cards (0-3 scale) as well as peak flow measurements in am/pm for a period of 2 weeks prior to budesonide administration (control data) and until completion of study. Only 12 (mean age: 9 years) of the initial patients were able to properly keep a diary and scheduled visits for a period of 15 weeks.Data allowed comparison between pre- and post-treatment symptoms/signs scores and PF values. After 3 weeks treatment with budesonide, statistically significant improvements were shown for all parameters, except for PF, whose minor improvements did not reach statistical significance.Budesonide CFC 400 microg administered once a day seems effective in control of asthma signs/symptoms within study design. Confirmation of the above findings in larger groups of patients, treated similarly and for longer periods of time, seems justified. A simple cost-effective intervention, analogous conceptually to the proven successful oral rehydration therapies for diarrhea in public health, should be considered in third world countries with high urban asthma prevalence.

In 1997 the Sun and the Earth passed through the equatorial plane of Jupiter and therefore through the orbital planes of its main satellites. During this period, mutual eclipses and occultations occurred and were observed. We investigate the precision of the catalogue to produce improved data for the development of dynamical models. Light curves of mutual eclipses and occultations were recorded by the observers of the international campaign PHEMU97 organized by the Institut de Mecanique Celeste, Paris, France. We made 275 observations of 148 mutual events from 42 sites. For each observation, information is given about the telescope, the receiver, the site and the observational conditions. This paper gathers together the data and gives a first estimate of the precision. The catalogue of these rare events represents a collection of improved accurate astrometric data useful for the development of dynamical models.

To study the possible effects of Furosemide at the lung level, two groups of isolated rabbit lung preparation were studied. An experimental group underwent a pulmonary hydrostatic oedema when the pressure of the left auricle (PAI) was increased from 0.45 +/- 0.74 t0 11.8 +/- 2.9 cm of H2O, with that increase in PAI we obtained an increase of 0.457 +/- 0.51 g/min in FFR (Fluid Filtration Rate), during this stable and sustained oedema, a 2 mg/Kg dosis of Furosemide was injected every 10 minutes and the possible changes in PAP, PAI, PVA, TFL, PaO2, PaCO2 and pH was observed, but no changes were observed in these parameters during the Furosemide infusion, and the same effect was observed in the control group were the preparations were maintained in basal conditions and without oedema. These results suggests that the Furosemide hat not a direct cardio-pulmonary effects, and the only possible effects could be by increasing diuresis at renal level.

5-Hydroxytryptamine1C (5-HT1C) recognition sites were characterized in rat spinal cord using [3H]mesulergine. In competition experiments with different 5-HT receptor agonists and antagonists, the rank order of drug potencies was consistent with drug affinities for the 5-HT1C receptor: mesulergine, mianserin, 5-HT greater than ketanserin, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane greater than 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)1H-indole, spiperone greater than 8-hydroxy-2-(di-n-propylamino)tetralin, pindolol. Bmax was 3.7 +/- 0.3 pmol/g and Kd 1.7 +/- 0.1 nM, with sites found in cervical, thoracic and lumbosacral cord. Inclusion of 20 nM spiperone to block potential 5-HT2 sites did not significantly alter drug affinities. There was a high correlation between drug affinities for [3H]mesulergine-labeled 5-HT1C sites in spinal cord and those reported in pig cortex (r = 0.94) and choroid plexus (r = 0.93), but poor correlation with 5-HT2 (high or low affinity states) or other 5-HT sites. Unlike [3H]mesulergine, the specific binding of [3H]5-HT, [3H]mianserin and [3H]ketanserin was low and no saturation studies could be performed with [3H]1-4-bromo-2-5-dimethoxy phenylisopropylamine. Limited competition studies suggest that [3H]5-HT labels 5-HT1C sites, [3H]ketanserin labels spinal 5-HT2 sites and [3H]mianserin labels both sites under the assay conditions studied, but the population of spinal 5-HT2 is small and not well characterized by these [3H]radioligands. In contrast, the population of spinal 5-HT1C receptors is substantial and [3H]mesulergine is the most useful [3H]radioligand for studies of spinal 5-HT1C sites.

To study the purported relation of 5-HT 1A and 5-HT 2 receptors, we chronically injected rats with a low dose of selective 5-HT agonists to induce behavioral tolerance and then tested for cross-tolerance. Acutely, in naive rats, both the putative 5-HT 2 agonist DOI and 5-HT 1A agonist 8-OH-DPAT induced some behaviors of the “serotonin syndrome” but the two drugs could be differentiated. Only DOI evoked shaking behavior, “skin jerks” (spinal myoclonus), and hyperthermia. Only 8-OH-DPAT induced flat body posture, head weaving, hypothermia, and occasional hindlimb hyperextension (dystonic posture). Both drugs, especially 8-OH-DPAT, evoked forepaw taping. Chronic (21 day) treatment with DOI prevented DOI-evoked behaviors but not behaviors evoked by 8-OH-DPAT. Behaviors evoked by 8-OH-DPAT and not DOI decreased significantly after chronic 8-OH-DPAT treatment. Development of selective tolerance suggests that putative selective 5-HT 2 and 5-HT 1A agonists exert shared and distributive behavioral effects through separate sites whose relation is behavior-specific. For some behaviors (forepaw myoclonus, shaking behavior, thermoregulation), there is functional interaction between 5-HT 1A and 5-HT 2 sites, while for other behaviors (skin jerks, flat body posture, head weaving), there is no interaction.

Groups of female rats were used throughout the 4-days estrous cycle and the accumulation of noradrenaline and its efflux were studied after incubation with the labelled amine. Comparisons were made between uterine horns corresponding to each one of the 4 stages of the cycle, i.e., diestrus, proestrus, metestrus and estrus.

Groups of female rats were used throughout the 4-days estrous cycle and the accumulation of noradrenaline and its efflux were studied after incubation with the labelled amine. Comparisons were made between uterine horns corresponding to each one of the 4 stages of the cycle, i.e., diestrus, proestrus, metestrus and estrus. Accumulation in diestrus reached the highest value, which was 1.64-fold higher than in estrus. An estimate of the original distribution of the amine into the extraneuronal and neuronal compartments of the tissue was obtained by compartmental analysis of the efflux curves. Size and half times of neuronal and extraneuronal compartments showed some relationship with the stage of the cycle.

The sensitivity of various isolated organs to catecholamines was tested before and after block of catechol-O-methyl transferase (COMT) by U-0521 (3′,4′-dihydroxy-2-methyl propiophenone; 18 μg/ml for 20 min). Isolated Nictitating Membrane of the Cat. The sensitivity to catecholamines was increased by inhibition of COMT whenever the experimental conditions resulted in a high potency of the amine, i.e., when the ED50 of the amine (in the absence of U-0521) was below about 10−6 M. Thus, block of COMT potentiated the effects of (−)-noradrenaline and (−)-adrenaline after denervation (or in the presence of cocaine) but not on muscles with an intact adrenergic innervation; it also increased the sensitivity to theβ-effects but not to theα-effects of isoprenaline. No potentiation was observed for dopamine which has a low potency even after denervation. The relation between potency of the catecholamine and the degree of the sensitizing effect of U-0521 was not due to saturation of COMT or of access to the enzyme. Measurements in denervated muscles of the production of O-methylated metabolites from (±)-noradrenaline-H3 (added to the bath for 20 min in concentrations of about 10−7 to 10−4 M), and of the extraneuronal accumulation of noradrenaline-H3 did not reveal any saturation of either the enzyme or the extraneuronal accumulation of the amine. When block of COMT resulted in supersensitivity to a catecholamine, the time required to reach steady-state responses was usually increased. This is consistent with the view that block of the enzyme impaired a site of loss. Block of COMT failed to produce any substantial potentiation of the effects of the indirectly acting amines, tyramine and mephentermine. O-methylation of the released transmitter seems to occur after the amine has reached the receptors of the effector cells. Isolated Strips of Cat and Bat Spleen. Results were quantitatively similar, since block of COMT potentiated the effects of (−)-noradrenaline and (−)-adrenaline in the presence but not (or only very little) in the absence of cocaine. However, the degree of supersensitivity after block of COMT (in the presence of cocaine) was smaller than in the nictitating membrane. In the cat spleen, cocaine causes a small but significant degree of supersensitivity to isoprenaline but not to methoxamine. Isolated Sat Aorta, Block of COMT did not increase the effect of cocaine. It is suggested that differences in the morphology of the adrenergic innervation contribute to the observed organ differences.

1. The effect of 5-hydroxytryptamine (5-HT) was studied on the nictitating membrane (isolated, or in situ in the pithed cat) and on strips of spleen capsule of the cat. 2. On the nictitating membrane 5-HT (in low concentrations) has a direct effect on tryptamine-receptors as well as (in high concentrations) an indirect effect which involves uptake of 5-HT into the adrenergic neuron via the cocaine-sensitive mechanism and release of noradrenaline. 3. On splenic strips 5-HT has a predominantly indirect effect. 4. The direct effects of 5-HT on the nictitating membrane are not increased by denervation (2 days), cocaine or block of monoamine oxidase (MAO), while decentralization (14 days) leads to supersensitivity to this amine. 5. The direct effects of 5-HT are resistant to phentolamine; the indirect effects are increased by block of MAO. This potentiation is probably due to prevention of deamination of both the 5-HT and the released noradrenaline. 6. The indirect effects of 5-HT are very similar to those of tyramine, and cross tachyphylaxis was observed. 7. Saturation of the tryptamine receptors of the nictitating membrane leads to desensitization. In addition, 5-HT antagonizes the effects of noradrenaline on the alpha-receptors. Apparently, a variety of interactions is possible between 5-HT and noradrenaline: at the alpha-receptors, at the cocaine-sensitive neuronal uptake mechanism and at the storage sites which retain the transmitter available for release by indirectly acting amines.

The Italian Medicina Radioastronomy Station (nearby Bologna) is equipped with two antennas: the 32 mt (VLBI) dish and the Northern Cross, a large T-shaped parabolic/cylindrical antenna (30.000 sqm). So far Seti observations have been performed using a SERENDIP IV high resolution spectrometer connected to the VLBI dish in “piggy back” mode configuration. In order to facilitate data interpretation and to introduce innovative methods to search for possible extraterrestrial signals, we are planning to make use of the large UHF Northern Cross transit telescope. Sky observations performed at least within two months, could provide for each day a number of matrices labeled according to the observing sidereal time. The entire set of matrices will be characterized by an averaged spectrum on each row per day. Keeping constant the transit antenna declination, a coherent signal coming from a definite position of the sky, would produce a “flag on” in the same submatrix at the same sidereal time. Detections collected in this way could be considered “confirmed” since they always come from the same region of the sky and are observed regularly. An extremely powerful processing board based on a multi-FPGAs (Field Programmable Gate Array) core was developed and is now under programming. This is conceived to be the processing core for this new kind of investigations.