Search

BL Lac objects have been found to be the largest population of emitters in gamma-ray band. However, since they are relatively weak radio sources, their parsec scale structure and most of their radio properties are poorly known. To increase our knowledge of the BL Lac object population, we selected a sample of BL Lacs from the BZ Cat at low redshift (z < 0.2), with no constrain on the radio flux density and gamma-ray activity. We present here the results of a first VLBA observation at 8 and 15 GHz and shortly discuss their properties

Context. The advent of Fermi is changing our understanding on the radio and gamma-ray emission in Active Galactic Nuclei. Contrary to pre-Fermi ideas, BL Lac objects are found to be the most abundant emitters in the gamma-ray band. However, since they are relatively weak radio sources, most of their parsec-scale structure and their multi-frequency properties are poorly understood and/or have not been investigated in a systematically fashion. Aims. Our main goal is to analyze the radio and gamma-ray emission properties of a sample of 42 BL Lacs selected, for the first time in the literature, with no constraint on their radio and gamma-ray flux densities/emission. Methods. Thanks to new Very Long Baseline Array observations at 8 and 15 GHz for the whole sample, we present here fundamental parameters such as radio flux densities, spectral index information, and parsec-scale structure. Moreover, we search for gamma-ray counterparts using data reported in the Second Catalog of Fermi Gamma-ray sources. Results. Parsec-scale radio emission is observed in the majority of the sources at both frequencies. Gamma-ray counterparts are found for 14/42 sources. Conclusions. The comparison between our results in radio and gamma-ray bands points out the presence of a large number of faint BL Lacs showing "non classical" properties such as low source compactness, core dominance, no gamma-ray emission and steep radio spectral indexes. A deeper multiwavelength analysis will be needed.

Vengono analizzate le principali innovazioni tecnologiche che, a partire dalle classiche sequenze spin-eco, hanno permesso di ridurre i tempi di acquisizione delle immagini in corso di indagini di RM. In particolare sono state considerate le tecniche di acquisizione con angolo di eccitazione inferiore a 90°. Di ciascuna viene sottolineata la strategia di implementazione, le difficoltà che è stato necessario superare e le possibili potenzialità positive nell'applicazione clinica.

Diffuse radio sources in clusters remain a poorly understood phenomenon. They are very extended sources (0.4-0.6 Mpc), of low surface brightness and steep spectrum, which cannot be identified with any active radio galaxy. They are a rare phenomenon, as they have been found so far in few clusters of galaxies. This paper reviews the current findings about this kind of sources, and the suggestions about their formation and evolution.

A cooled telescope (250 mm, F/2) has been designed and prepared for measurements of both local and cosmological Near Infrared backgrounds in the waveband 1–5 μm at balloon altitudes (40 km). The separation of various foreground contributions should be possible by applying observing strategies based on multiple sky scans with different filters. The whole apparatus will be tested in flight by using a detection system based on a linear array of 32 InSb pixels cryogenically cooled and thermally controlled at 52 K. The instrument sensitivity will allow the measurement of most of the local backgrounds. The focal plane could be easily re-arranged to house bidimensional array detectors cooled down to ∼ 35 K with performance improvements of a factor at least 100 ÷ 200. A description is given of the main characteristics of the instrument (optics, cryostat, detector), of the control subsystems (cryogenics, pointing systems, electronics, ground equipment) and of the expected performance based on laboratory test results.

We analyze Chandra observations of diffuse soft X-ray emission associated with a complete sample of 3CR radio galaxies at z < 0.3. In this paper we focus on the properties of the spectroscopic sub-classes of high excitation galaxies (HEGs) and broad line objects (BLOs). Among the 33 HEGs we detect extended (or possibly extended) emission in about 40% of the sources; the fraction is even higher (8/10) restricting the analysis to the objects with exposure times larger than 10 ks. In the 18 BLOs, extended emission is seen only in 2 objects; this lower detection rate can be ascribed to the presence of their bright X-ray nuclei that easily outshine any genuine diffuse emission. A very close correspondence between the soft X-ray and optical line morphology emerges. We also find that the ratio between [O III] and extended soft X-ray luminosity is confined within a factor of 2 around a median value of 5. Both results are similar to what is seen in Seyfert galaxies. We discuss different processes that could explain the soft X-ray emission and conclude that the photoionization of extended gas, coincident with the narrow line region, is the favored mechanism., Comment: 15 pages, 11 figures. Accepted for publication on A&A

An old-growth beech forest stand with silver fir within the strict forest reserve of Sasso Fratino has been examined with the following aims: to characterize forest stand on the basis of classic forest parameters and to assess forest stand structure by means of spatial functions; to provide genetic dating of the beech population. Total census of size and position of living trees and deadwood was performed on a 9200 m2 permanent plot. Vertical distribution of crowns in the stand was assessed using the TSTRAT function, horizontal stand structure using spatial point pattern analysis. Genetic dating was performed on a sample of beech trees. DNA was isolated and each individual was genotyped at four chloroplast microsatellite loci. Microsatellite profiles were compared with the profiles of control DNA of known haplotypes. Results show a multi-strata vertical structure, a horizontal structure characterized by small gaps (5160 m2) where silver fir regeneration sets in. Deadwood is present with all the decay classes and with relatively high volumes. Genetic dating ascribes the Sasso Fratino beech stand to the ancestral haplotype 2: this population can therefore be considered a hot spot of haplotype diversity of the glacial refugia present in central Italy.

Radio halos are elusive sources located at the center of merging galaxy clusters. To date, only about 40 radio halos are known, thus the discovery of new halos provide important insights on this class of sources. To improve the statistics of radio halos, we investigated the radio continuum emission in a sample of galaxy clusters. We analyzed archival Very Large Array observations at 1.4 GHz, with a resolution of about 1 arcmin. These observations complemented by X-ray, optical, and higher resolution radio data allowed to detect a new radio halo in the central region of A800 and A1550. We discovered a radio relic in the periphery of A910, and finally we revealed both a halo and a relic in CL1446+26.Clusters hosting these new halos show an offset between the radio and the X-ray peak. By analyzing this offset statistically we found that radio halos can be quite asymmetric with respect to the X-ray gas distribution, with an average radio - X-ray displacement of about 180 kpc. When the offsets are normalized by the halo size, there is a tendency for smaller halos to show larger displacements., Accepted by Astronomy and Astrophysics, 13 pages, 8 figures

The aim of this work is to investigate the possible presence of extended diffuse synchrotron radio emission associated with the intracluster medium of the complex galaxy cluster A1689. The radio continuum emission of A1689 has been investigated by analyzing archival observations at 1.2 and 1.4 GHz obtained with the Very Large Array in different configurations. We report the detection of an extended, diffuse, low-surface brightness radio emission located in the central region of A1689. The surface brightness profile of the diffuse emission at 1.2 GHz indicates a central radio brightness of ~1.7 \mu Jy/arcsec^2 and the 3\sigma radio isophothes reveal the largest linear size to be 730 kpc. Given its central location, the low-level surface brightness, and the comparatively large extension, we classify the diffuse cluster-wide emission in A1689 as a small radio halo., Comment: 8 pages, 6 figures, A&A accepted

We report on our Chandra Cycle 9 program to observe half of the 60 as yet unobserved 3C radio sources at z

Here we present the first case of a Compact Steep Spectrum (CSS) radio galaxy, 3C 305, in which the X‐ray radiation appears to be associated with the optical emission line region, marked by the [O III]5007. On the basis of a morphological study, performed using the comparison between the X‐rays (Chandra), the optical (HST) and the radio (VLA) data, we argue that the high energy emission has a thermal nature. Finally, we discuss the origin of the extended X‐ray structure connected with the optical emission line region following two different interpretations: as due to the interaction between matter outflows and shock‐heated environment gas, or as due to gas photoionized by nuclear emission.

In three general medical settings (general practice, hospital medical wards and emergency rooms) about 20% of the adult attenders had a DSM-III mental disorder, mainly in the area of affective and anxious disorders. Some of these disorders were quite severe. Of those cases reassessed 1 year and 2 years after the first interview, less than a quarter reached a "no-diagnosis status". The chronicity of most cases dependent on the interplay not only of either relapse or duration of the main disorder but also of comorbidity and incidence of new disorders. A high incidence of more transient disorders in subjects who were well at first assessment was also found.

We present a statistical study on parsec scale properties of a sample of Brigthest Cluster Galaxies (BCGs) in Abell Clusters. These data show a possible difference between BCGs in cool core clusters (two-sided parsec scale jets) and in non cool core clusters (one-sided parsec scale jet). We suggest that the two-sided morphology in cool core clusters could be due to the presence of mildly relativistic jets slowed down already at mas scale as consequence of the jet interaction with a dense surrounding medium., Comment: 4 pages, 2 figures, To appear in Proceedings of Science: "The Monsters Fiery Breath: Feedback in galaxies, groups, and clusters, Fluno Center, Madison Wisconsin, 2009 June 1-5"

We present here a ballon-borne experiment to measure the near-infrared cosmological background in the (1÷5) μm range. The instrument, a liquid helium cooled telescope (250 mm,F/2), was built in the infrared laboratory of Istituto TE.S.R.E./C.N.R.-Bologna (Italy) collaboration with the Haverford College (PA-U.S.A.). It will be launched from the NSBF base of Palestine (Texas-U.S.A.) in May 1989.

We present the analysis of VLA and VLBA observations of the radio source 3C 338, associated with the cD galaxy NGC 6166, the central dominant galaxy of the cluster Abell 2199. The VLBA observations were done at 8.4 and 15.4 GHz, while the VLA observations were performed at 0.074, 0.330, and 8.4 GHz. The milliarcsecond resolution VLBA data, spanning 7 years, reveal the parsec-scale jets, whose kinematics and orientation cannot be unambiguously derived. Based on the observed morphology, jet/counter-jet length ratio, flux density ratio, and proper motions of the jet components, we consider two possible explanations: either the jets are strongly relativistic and lie within 10 - 20 degrees of the plane of the sky, or they are only mildly relativistic, and are pointing at an angle between 30 - 50 degrees from the plane of the sky. The arcsecond resolution VLA data enable us to investigate the large scale structure of the radio source. The morphology of the low frequency radio lobes clearly indicates that they are associated with the cavities present in the X-ray emission. Low frequency observations also reveal an extension to the south corresponding to an X-ray hole. The age of these bubbles, computed from the sound speed, the buoyancy time and the radiative age are all in fair agreement with each other. Estimates of the power necessary to inflate these cavities suggest that the accretion power onto the central engine has not been constant over time., 13 pages, 11 figures (3 in colour). Accepted for publication in ApJ

We present new radio observations of 9 members of a sample of 29 nearby (z < 0.2) BL Lac objects. The new data have been obtained with the European VLBI Network and/or the MERLIN at 1.6 and 5 GHz and complement previous observations. For one object, the TeV source Mrk 421, we also present deep multi-epoch VLBA and Global VLBI data, which reveal a resolved diffuse jet, with clear signatures of limb brightening. We use the new and old data to estimate physical parameters of the jets of the sample from which the subset with new radio data is drawn. We derive Doppler factors in the parsec scale radio jet in the range ~2 < delta < ~9. Using HST data, we separate the contribution of the host galaxy from that of the active core. From the measured and de-beamed observables, we find a weak correlation between radio power and black hole mass, and a tight correlation between radio and optical core luminosities. We interpret this result in terms of a common synchrotron origin, with little contribution from a radiatively efficient accretion disk. The BL Lacs in our sample have de-beamed properties similar to low power radio galaxies, including the fundamental plane of black hole activity., Accepted by ApJ. 17 pages

This study evaluated the prevalence and determinants of low back pain (LBP) in Terni hospital workers. Each ward sister completed a questionnaire about potential determinants of LBP associated with physical loads. Moreover, a trained ward sister administered a questionnaire about the characteristics of low back pain to 512 subjects. In the previous year the prevalence of LBP was 58.8%. It was more common in subjects under 45 years of age.3 LBP episodes annually were more frequent in operating rooms and medical wards. LBP lasted1 week in 29% of females and in 23% of males. LBP caused change of duties or time off work in 11% of females and in 8% of males.

Using a combination of observations involving the VLA, MERLIN and global VLBI networks we have made a detailed study of the radio continuum and the neutral hydrogen (HI) kinematics and distribution within the central kiloparsec of the radio galaxy 3C293. These observations trace the complex jet structure and identify the position of the steeply inverted radio core at 1.3GHz. Strong HI absorption is detected against the majority of the inner kiloparsec of 3C293. This absorption is separated into two dynamically different and spatially resolved systems. Against the eastern part of the inner radio jet narrow HI absorption is detected and shown to have higher optical depths in areas co-spatial with a central dust lane. Against the western jet emission and core component, broad and complex HI absorption is detected. This broad and complex absorption structure is discussed in terms of two possible interpretations for the gas kinematics observed: that the gas is situated in two gas layers or that it is in a sub-kiloparsec disk rotating about the core. (Abridged), 14 pages, 8 figures, To be published in MNRAS. High resolution version is available at http://www.jb.man.ac.uk/~rbeswick/3c293-paper.html

The existence of magnetic fields associated with the intracluster medium in clusters of galaxies is now well established through different methods of analysis. Magnetic fields are investigated in the radio band from studies of the rotation measure of polarized radio galaxies and the synchrotron emission of cluster-wide diffuse sources. Other techniques include X-ray studies of the inverse Compton emission and of cold fronts and magneto hydrodynamic simulations. We review the main issues that have led to our knowledge on magnetic fields in clusters of galaxies. Observations show that cluster fields are at the

The extracellular levels of aspartate, glutamate, gamma-aminobutyric acid (GABA), and acetylcholine (ACh) were investigated by microdialysis, coupled with HPLC, in the ventral hippocampus of rats during two 30-min exploration periods. Motor activity was monitored. During exploration I, an increase in motor activity associated with a 315% increase in aspartate, 181% in glutamate, and 264% in ACh levels, occurred during the first 10 min. The increase in GABA level reached a maximum of 257% during the second 10 min. The neurotransmitter levels returned to basal values within 40 min. During exploration II, 1 h later, a smaller increase in neurotransmitter levels and motor activity was observed. In both explorations, the increase in neurotransmitter levels was completely abolished by 1 and 3 microM TTX. A statistically significant relationship was found between neurotransmitter extracellular levels and motor activity, for aspartate and glutamate in exploration I, and for ACh in exploration I and II. In conclusion, exploratory activity is associated with or depends on the activation of neuronal systems in the ventral hippocampus releasing aspartate, glutamate, GABA, and ACh. The activation is dampened by habituation.

[1] The results of the environmental radiation (ER) monitoring obtained during the Tunguska expedition of July 1999 with a NaI(Tl) scintillation detector are reported. Some interesting meteorological effects related to the airborne radioactive components (radon and thoron decay products) have been observed. The main effects observed are (1) the doubling of the ER during two quite different rain-out episodes and (2) a fairly regular diurnal wave in the intensity of the total radiation. The rain-out phenomenon allows us to approximate the timescale for the removal by precipitation of radioactivity from the air, while the wave phenomenon gives us the opportunity to develop a simplified model for estimating the time-averaged, dry weather surface radon concentration.

Systematic integration of ECG, RIsk and Chest pain (ERIC) analysis and evaluation of the ST segment of single and serial ECG recordings can help recognize early the main forms of acute myocardial ischemia and allow doctors to select candidates for thrombolysis, emergency angioplasty or by-pass surgery. The integration of these different sources of knowledge is still difficult to achieve in emergency situations such as during ambulance transportation. To fill this gap a portable cardiological station equipped with computerized diagnostic support has been designed for emergency cars, both to help on-site decision-making and to establish a continuous link between the ambulance and the cardiology department. The use of such a system inside and outside the hospital will improve the quality of the decision-making process outside the hospital and exploit the main resources in specialized departments, mainly by gaining precious time in a preselected set of patients.

Two highly productive emergent macrophytes, Zizaniopsis bonariensis and Typha subulata were established in experimental subsurface flow, sand-based wetlands receiving anaerobically treated municipal wastewater. The hydraulic loading rate was tested in two levels, sequentially, 6.8 cm x d(-1) and 13.6 cm x d(-1), for 70 days each. In the 13.6 cm x d(-1)-loading treatment, among all monitored variables only COD, PO4-Total-P, and Turbidity were removed more efficiently by the planted beds in comparison to unplanted sand beds (P0.001). When the 6.7 cm x d(-1)-loading rate was applied no significant improvement in removal was found comparing macrophyte beds to unplanted sand beds, except for PO4-P. T. subulata beds were significantly more efficient than Zbonariensis beds for most of the variables. The highest significant differences (P0.001) were related to the main effect of the factor hydraulic loading rate, with decreased removal for increased load when considering the variables Total Coliforms (99.4% to 87.7%), Fecal Coliforms (100% to 89.7%). NH3-N (95.8% to 55.2%), NO3(-)-N (-54% to -396%), Total-N (90.4% to 59.6%), and TSS (86.1% to 46.1%). The performance similarity of planted and unplanted wetland beds in the lower loading condition, except for PO4-P, indicates that plants may not be needed under low loading. However aquatic macrophytes improved wetland efficiency under high loading.

Preface. Contributing Authors. 1. The Physics of Cluster Mergers C.L. Sarazin. 2. Optical Analysis of Cluster Mergers M. Girardi, A. Biviano. 3. X-Ray Observations of Cluster Mergers D.A. Buote. 4. High Angular Resolution Cluster Observations with Chandra W. Forman, C. Jones, M. Markevitch, A. Vikhlinin, E. Churazov. 5. Observational Signatures and Statistics of Galaxy Cluster Mergers H. Bohringer, P. Schuecker. 6. Radio Galaxies and their Environment L. Feretti, T. Venturi. 7. Diffuse Radio Sources and Cluster Mergers G. Giovannini, L. Feretti. 8. Mergers of Galaxy Clusters in Numerical Simulations S. Schindler. 9. Clusters, Cosmology and Mergers A.E. Evrard, I.M. Gioia. Index.

BACKGROUND The aim of the present study is to investigate the levels of some of the cytokines which may be involved in the mechanisms leading to the impairment of placental perfusion and to the onset of uterine contractions in pregnancies with fetal genetic abnormalities compared with controls. METHODS The amniotic fluid and maternal plasma levels of interleukin-6, interleukin-8 and tumour necrosis factor-beta in patients with fetal chromosomal abnormalities were measured, as well as in euploid pregnancies in the seventh week of gestation. RESULTS An increase of interleukin-6 (P = 0.034) and a decrease of interleukin-8 (P < or =0.0001) in amniotic fluid, and a decrease of interleukin-6 in the maternal plasma (P = 0.026) was shown in pregnancies with fetal chromosomal abnormalities. A positive correlation was observed between amniotic interleukin-8 and serum interleukin-6 in the presence of fetal aneuploidy (P < 0.006). CONCLUSION Further investigations of cytokine imbalance in pregnancies with poor outcome as a consequence of genetic disorders rather than infection is warranted.

We have constructed a new sample of 84 large angular size radio galaxies selected from the NRAO VLA Sky Survey (NVSS). Radio sources with declination above +60°, total flux density greater than 100 mJy at 1.4 GHz and angular size larger then 4′ have been selected and observed with the VLA at 1.4 and 4.9 GHz. A number of peculiar radio galaxies have been discovered, of which we present here results on J1835+620, J2114+820 and J2157+664.

The teat is the main entrance for pathogens into the mammary gland. It also acts as a sensory, motor and primary defence organ. This latter function is important in preventing intramammary infections while efficiency in preventing new infections is determined by teat tissue integrity. Machine milking may evoke mechanical and circulatory impairment in teat tissues. These local metabolic disorders may decrease the efficiency of the local immune defence mechanisms. Teat tissue changes can be estimated by measuring teat thickness before and after milking. Experimental and field studies showed a high correlation between changes in thickness and infection risk. Teats with5% change in thickness have significantly increased teat duct colonisation rates and intramammary infection rates. The link between changes in teat thickness and infections should be found in changes in local immune defences and measurable changes in cytological and biochemical immune factors are expected. Indeed, the application of experimental milking conditions (i.e. no pulsation milking and positive pressure milking) showed to have a significant influence on some non specific immune factors in teat secretion. Positive pressure milking increases PMNs content and decreases macrophages content of teat secretion. Some enzymes such as NAGase and lysozyme were decreased by positive pressure milking, the concentration of the same enzymes were higher after no pulsation milking. A better knowledge on the interaction between the teat apex immune defense mechanisms and the machine milking process is necessary to reduce the new infection rate of the bovine mammary gland.

Cortical perfusion with GABA agonists and antagonists modulates the spontaneous release of cortical acetylcholine and GABA in freely moving rats. Twenty-four hours after implantation of a dialysis fibre, cerebral cortex spontaneously released acetylcholine (3.8 +/- 0.2 pmol/10 min) and GABA (6.6 +/- 0.4 pmol/10 min) at a stable rate. Local administration of GABA (1 or 5 mM) or the GABAA agonist muscimol (25 or 50 microM) had no effect on the spontaneous release of acetylcholine. However, bicuculline (1-25 microM), a GABAA antagonist, added to the dialysis perfusate, elicited a concentration-dependent increase of acetylcholine release to approximately double that of control. This effect of bicuculline (25 microM) was completely prevented by coperfusion with muscimol (50 microM). Local administration of the GABAB receptor agonist baclofen (10 or 50 microM) elicited a concentration-dependent increase in spontaneous acetylcholine release with a maximal increase of about 60%. Intracortical administration of baclofen also decreased the spontaneous release of GABA. The GABAB receptor antagonist CGP 35348 (1 mM), administered alone for 20 min through the dialysis fibre, was without effect on spontaneous acetylcholine release; however, it completely blocked both the baclofen-induced increase in acetylcholine release and the decrease in GABA release. These results suggest that cortically released GABA exerts a tonic influence on cholinergic activity.

A vast number of substances have been suggested as possibly contributing to perturbation of the endocrine system. Several have been tested with different approaches ranging from yeast expression system of human oestrogenic receptors to human breast cancer cells assays. Surprisingly, no inhibition-binding experiments to steroid receptors on healthy human tissue have been performed so far. Our study provides inhibition binding experiments to oestrogens, progesterone, testosterone and retinoic acid receptors in prostate and uterine human tissue of organochlorine pesticides, phthalate esters, oestrogenic constituents derived from plants and phenol derivates. Affinities of significant extent of phthalates on oestrogenic, progestinic and androgenic receptors have not been detected. As for retinoic acid receptors, mono(2-ethylexyl)phthalate provokes a notable reduction of the binding of the tritiated retinoic acid, phtalic acid ethyl-n-butyl ester and 4-octylphenol show an affinity comparable to that of isoflavonoid genistein, whereas 4-nonylphenol reduces the binding of retinoic acid in prostate.

Late side effects of alpha-interferon therapy include some autoimmune diseases, such as thyroiditis. We present the case of a patient with severe chronic active hepatitis and hepatitis-C-virus positivity, who during alpha-interferon therapy developed an autoimmune thyroiditis and at the same time arthropathy with some characteristics of rheumatoid arthritis (several articular stations simultaneously affected, involvement of the hand joints and morning stiffness).

Observations of the core of the giant radio galaxy NGC315 made with VLBI interferometers are discussed in the context of a relativistic jet. The sidedness asymmetry suggests Doppler favoritism from a relativistic jet. The presence of moving features in the jet as well as jet counter--jet brightness ratios hint at an accelerating, relativistic jet. An increasing jet velocity is also supported by a comparison of the jet's observed properties with the predictions of an adiabatic expansion model. On the parsec scale, the jet is unpolarized at a wavelength of 6 cm to a very high degree in clear distinction to the high polarization seen on the kiloparsec scale., Comment: 24 pages with 8 figures. ApJ in press

The Coma cluster is a rich cluster of galaxies nested in an even larger supercluster of galaxies. The plane of the supercluster appears to be defined by the Coma cluster itself and another galaxy cluster, Abell 1367, that lies about 40 Mpc (H0 = 75 Mpc km−1s−1 (≡h75)) farther west (Tifft and Gregory 1976).

It has recently been suggested that inflammation may play an important role in the pathogenesis of acute ischemic syndromes. It may therefore be important to relate their clinical features with plasma indexes of inflammation. We have studied leukocyte, platelet and fibrinogen blood levels in 57 consecutive patients with acute myocardial infarction admitted to our Intensive Care Unit within 90 min after the onset of chest pain and treated with primary coronary angioplasty. Patients were divided into two groups on the basis of blood leukocyte levels: Group A, 24 patients, 17 males, mean age 54.2 +/- 13.7 years, with high blood leukocytes and Group B, 33 patients, 28 males, mean age 60.9 +/- 10.3 years, with normal blood leukocytes. Group A patients also had higher serum fibrinogen (p = 0.05) and blood platelet levels (p0.05). The stenosis observed after guidewire advancement was significant (75%) in 33% of the patients with leukocytosis vs 94% of the others (p0.01). No difference between the two groups was observed in the success rate of coronary angioplasty and prevalence of stent placement (100 vs 97%, and 43 vs 42% of the patients of Group A and B, respectively). In contrast, a tendency to rethrombosis requiring Rheopro administration was observed in 62% Group A patients vs 21% Group B patients (p0.01). In conclusion, the finding of leukocytosis in the acute phase of myocardial infarction suggests that coronary occlusion is mainly caused by a coronary thrombus occurring at the site of a non significant stenosis. In contrast, when blood leukocytes are normal, the underlying coronary stenosis is more often critical and the thrombotic process is less important. The high blood leukocytes, platelet and fibrinogen levels of Group A patients are consistent with a significant role of inflammation in the pathogenesis of the thrombotic process while hemodynamic and local mechanical factors are probably more important in patients with normal blood leukocytes.

We have observed the radio source NGC 3862 (3C264) simultaneously with the EVN and the MERLIN arrays, obtaining detailed images of its radio structure from parsec to sub-kiloparsec scales. 3C264 shows a one-sided jet, with evident variations in its morphological properties with distance. We have analyzed HST optical data of NGC 3862 finding a one-to-one correspondence between radio and optical features in the jet. The radio to optical spectral index is approximately constant along the jet. Synchrotron appears as the most plausible mechanism for the observed jet emission at radio and optical wavelengths. Local particle reacceleration or, alternatively, deviation from the condition of equipartition, are plausible mechanisms to explain the low synchrotron cooling and constant spectral index in the jet of 3C264., 5 figures - Accepted for the publication in the Astrophysical Journal

Nitric oxide (NO) play a pivotal role in many biological processes, as in the vessel tone control, the atherogenesis, the platelets aggregation and the immune system modulation. The physiologic precursor of NO is the L-arginine. Evidence exists that the L-arginine administration can stimulate immune system in children with recurrent infections. This clinical trial was designed to evaluate the effects of oral administration of L-arginine on the number of infective events and on the lymphocytes subsets in children suffering from airways recurrent infections.Forty outpatients, 21 male and 19 female, aging from 2 to 13 yrs. Two balanced groups, treated for 60 days with L-arginine or a placebo. Evaluation criteria: number of septic episodes; number of circulating white blood cells, % of the lymphocytes; lymphocytes subsets.Descriptive analysis; inference tests: chi 2; "t" test; variance analysis. Statistical significance: p = 0.05.Fifteen patients treated with L-arginine and five treated with placebo (p0.01) were free from infections. The percentage of CD3 and CD4 subsets significantly (p0.05) increased in the L-arginine group than in the placebo group, while the CD8 subset significantly decreased. The CD4/CD8 ratio raised from 1.05 +/- 0.29 to 1.51 +/- 0.46 (p0.01) in the L-arginine group, from 1.12 +/- 0.16 to 1.27 +/- 0.24 in the placebo group. There were no side effects in both groups.L-arginine seems able to increase the immune system defences and to protect against the airway infections.

Implantation of intracoronary stents has been rapidly increasing in the last few years, especially after a reduction of restenosis has been shown. The main limitation in the use of coronary endoprosthesis is still represented by acute and subacute thrombosis. In order to limit this dangerous complication a very strong coagulant regimen, which has been improved since 1993-94, was initially recommended. We report our experience with patients who underwent a stent implantation comparing two therapeutic regimens with or without oral coagulants associated with antiplatelet agents. During 700 consecutive coronary angioplasties 128 Palamatz-Schatz and Wiktor stents have been implanted in 118 patents (16.9%). After stent implantation, 33 patients underwent a traditional anticoagulant therapy with heparin followed by oral anticoagulants for 3 months. They were also treated with ticlopidine 250 mg/die started 2 days before the procedure and then kept at least one month (group A). Eighty-five patients were treated only with antiplatelet therapy (ticlopidine 500 mg/die) started 2 days before implantation (group B). These two groups of patients were similar in age, sex, type and number of treated vessels and in diameter of the vessel with stent implantation. Subacute thrombosis rate was not significantly different between groups (3 vs 2.3%, NS). The predictive factors of thrombosis were acute myocardial infarction and implantation of multiple stents. No significant differences were found between thrombosis of the stents implanted in bail-out conditions compared to the elective ones. Ticlopidine started 2 days before stent implantation seems to be sufficient to limit thrombosis rate; moreover it allows a reduction of the hemorrhagic complications and hospitalization period.

The aim of this study was the survey of cathepsin D determination in a large group of patients enrolled at several centers, under the coordination of the Italian Committee for Quality Control in the Oncological Laboratory. Cathepsin D was measured with the same method-ology, under control of an intra and interlaboratory quality control program, in order to verify the comparability of cathepsin D results from different institutions and to analyze the frequency of cathepsin D positive cases in subgroups of patients stratified according to other prognostic parameters. This retrospective study included 2575 patients with primary breast cancer evaluat-ed in 10 institutions. Cytosol from tumor tissue was the substrate for biochemical cathepsin D, estrogen receptor and progesterone receptor determination, with an interlaboratory quality control survey provided by the E.O.R.T.C. Receptor Group and the Italian Committee for Quality Control in the Oncological Laboratory. The results of the present study can be summarized as follows: 1) Cathepsin D is independent of menopausal status; 2) In spite of standardization of tissue handling and assay methods, different results may be obtained by different institutions. It is therefore essential that each laboratory calculates its own positive/negative cutoff values prior to any routine clinical use of the parameter. This should be a serious consideration when a multicenter study is planned.

We have performed sensitive observations of three classical head-tail radio galaxies at λ11.1, 6.3, and 2.8 cm using the Effelsberg 100-m telescope (Zech, 1994). Complete maps of the sources 3C129, NGC1265, and 3C465 were obtained, including the distributions of the linearly polarized intensity. Together with the low-frequency interferometric maps these allow a comprehensive study of their radio spectra and, based on models of particle losses, the derivations of particle ages across these sources. The highest frequency involved allows an unambiguous derivation of the projected magnetic field structure, unimpeded by Faraday effects. Here we focus on NGC1265, which is located in the Perseus Cluster.

Diffuse radio sources in clusters remain a poorly understood phenomenon. They are very extended sources (0.4-0.6 Mpc), of low surface brightness and steep spectrum, which cannot be identified with any active radio galaxy. They are a rare phenomenon, as they have been found so far in few clusters of galaxies. This paper reviews the current findings about this kind of sources, and the suggestions about their formation and evolution.

A cooled telescope (250 mm, F/2) has been designed and prepared for measurements of both local and cosmological Near Infrared backgrounds in the waveband 1–5 μm at balloon altitudes. The separation of various foreground contributions should be possible by applying observing strategies based on multiple sky scans with different filters. The whole apparatus will be tested in flight by using a linear array of 32 InSb detectors cryogenically cooled and thermally stabilized at 52 K. The instrument sensitivity will allow the measurement of most of the local backgrounds. A description is given of the flight instrumentation and of the expected performances based on laboratory test results.

The Fanaroff-Riley type I radio galaxies (Fanaroff & Riley, 1974) presented in this paper belong to the complete sample of low-intermediate luminosity radio galaxies published in Giovannini, Feretti & Comoretto (1990). This sample includes radio galaxies with different morphologies on the arcsecond scale, such as compact sources, core-halos, FRIs and FRIIs.

We shortly discuss here the parsec scale information presently available on the extended low power radio galaxy (FR I, Fanaroff and Riley, 1974) NGC6251 (Jones and Wehrle, 1994) and on 11 radio galaxies from the sample presented in Giovannini et al. (1990).

We undertook a project of observation of a complete sample of radio galaxies with the VLBI technique, in order to test: a) current models on jet dynamics and b) the radio source unified schemes. A preliminary analysis based on the data obtained by us for 10 galaxies of our sample indicates that the parsec scale structure in low power radio galaxies (FR-I) and high power radio galaxies (FR-II) is essentially the same.

In 62 cases of gynecological malignancies, 16 of the ovarian, 31 of the endometrium and 15 of the cervix, the EGF-R status was evaluated in order to establish its prognostic value and its correlation with other classical prognostic factors. We have failed to demonstrate any correlation between EGF-R status and stage, grade and hormonal receptors, ER/PgR, in ovarian and cervical cancer. In contrast, in endometrial cancer, we observed significantly lower levels of EGF-R in poorly differentiated tumors. Moreover, a weak negative relationship between EGF-R and PgR status was found. Regarding survival, we noticed a better prognosis in patients with ovarian cancer EGF-R positive, but without statistical significance.

The presence of heavy metals in contaminated soils represents one of the most important environmental hazards, and one of the most difficult problem to resolve. Escavation and transport of contaminated soil to landfill is very expensive and not completely safe. Alternative strategies for the clean-up of heavy metals contaminated sites are on-site treatments which, among the others, involve immobilisation processes and extractive techniques, where a solvent phase is mixed with soil and then separated by a screening step.