To evaluate the role of parenteral and sexual transmission of human immunodeficiency virus, we studied seronegative intravenous drug users recruited from 25 drug dependence treatment centers in ...northern Italy. All attending intravenous drug users were asked for their consent and screened for antibodies to human immunodeficiency virus; those who were seronegative were enrolled, interviewed about their habits, and invited to follow-up visits. Between 1987 and 1989, 1,195 seronegative intravenous drug users were enrolled, 635 were followed up (mean duration, 11.9 months), and 35 seroconversions were observed. The incidence rate ratios were 3.3 (95% confidence interval (CI) 1.4-7.5) for subjects aged less than 20 years, 2.4 (95% CI 1.2-4.7) for less than 2 years of intravenous drug use, 2.2 (95% CI 0.9-5.5) for syringe sharing, and 1.0 for subjects with a sexual partner who had tested positive for human immunodeficiency virus. A case-control approach, using logistic regression and adjusting for sex, age, area, and prevalence, showed odds ratios of 13.2 (95% CI 3.1-56.8) for frequent syringe sharing and 4.0 (95% CI 1.5-10.4) for sexual contacts with seropositive partners; frequent use of condoms was associated with a reduction in risk that did not reach statistical significance. Parenteral transmission is the most important route of infection with the human immunodeficiency virus among intravenous drug users, and sexual transmission plays a relevant, additive role.
We present the first Herschel PACS and SPIRE photometric observations in a portion of the outer Galaxy (\(216.5^{\circ} \lesssim \ell \lesssim 225.5^{\circ}\) and \(-2^{\circ} \lesssim b \lesssim ...0^{\circ}\)) as a part of the Hi-GAL survey. The maps between 70 and 500 \(\mu\)m, the derived column density and temperature maps, and the compact source catalog are presented. NANTEN CO(1-0) line observations are used to derive cloud kinematics and distances, so that we can estimate distance-dependent physical parameters of the compact sources (cores and clumps) having a reliable spectral energy distribution, that we separate in 255 proto-stellar and 688 starless. Both typologies are found in association with all the distance components observed in the field, up to \(\sim 5.8\) kpc, testifying the presence of star formation beyond the Perseus arm at these longitudes. Selecting the starless gravitationally bound sources we identify 590 pre-stellar candidates. Several sources of both proto- and pre-stellar nature are found to exceed the minimum requirement for being compatible with massive star formation, based on the mass-radius relation. For the pre-stellar sources belonging to the Local arm (\(d\lesssim1.5\) kpc) we study the mass function, whose high-mass end shows a power-law \(N(\log M) \propto M^{-1.0 \pm 0.2}\). Finally, we use a luminosity vs mass diagram to infer the evolutionary status of the sources, finding that most of the proto-stellar are in the early accretion phase (with some cases compatible with a Class I stage), while for pre-stellar sources, in general, accretion has not started yet.
Six species of Longidorus were found during a survey of longidorid nematodes carried out during 1996-2000 in fruit orchards in Switzerland. They are L. elongatus (De Man) Thorne et Swanger, L. ...macrosoma Hooper, L. profundorum Hooper, L. raskii Lamberti et Agostinelli, L. arthensis Brown, Grunder, Hooper, Klingler et Kunz and L. helveticus sp. n.. L. helveticus is a bisexual species characterized by body length of about 8 mm, odontostyle of about 135 micronm, hemi-elliptical lip region, continuous with the rest of the body, amphidial pouches not lobed, equally developed female genital branches and bluntly rounded tail. The first juvenile stage has a digitate tail. L. helveticus resembles L. macrosoma, L. poessneckensis Altherr, L. picenus Roca, Lamberti et Agostinelli and L. nevesi Macara. The six species are characterized by superoxide dismutase and esterase isozymes and by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of amplified ITS
Nel corso di un'indagine sui nematodi longidoridi svolta nel periodo 1996-2000 in frutteti svizzeri sono state ritrovate sei specie di Longidorus. Esse sono L. elongatus (De Man) Thorne et Swanger, L. macrosoma Hooper, L. profundorum Hooper, L. raskii Lamberti et Agostinelli, L. arthensis Brown, Grunder, Hooper, Klinger et Kunz e L. helveticus sp. n.. L. helveticus e' una specie bisessuale caratterizzata da una lunghezza corporea di circa 8 mm, odontostilo di 135 micronm, regione labiale semiellittica, continua con il resto del corpo, tasche anfidiali non lobate, branche genitali femminili ugualmente sviluppate e coda arrotondata. Il primo stadio larvale presenta coda digitata. L. helveticus assomiglia a L. macrosoma, L. poessneckensis Altherr, L. picenus Roca, Lamberti et Agostinelli e L. nevesi Macara. Le sei specie sono caratterizzate mediante gli isoenzimi della superossido dismutasi e dell'esterasi e mediante PCR-RFLP (reazione a catena della polimerasi-polimorfismo della lunghezza dei frammenti di restrizione) dell'ITS amplificato
Morphometric and molecular studies were undertaken of Floridian populations of Xiphinema vulgare Tarjan, 1964. All populations were found to be almost morphometrically identical with the type ...populations and those from Sao Tome'. Juveniles were clearly separated in four developmental stages. Isoelectric focusing profiles of specimen extracts stained for superoxide dismutase activity showed one or two close bands at pH 7.6 and 7.6/7.3, respectively. The PCR products of the ITS region were between 1 and 1.5 kb and were digested by six restriction enzymes
Sono stati intrapresi studi morfometrici e molecolari di popolazioni di Xiphinema vulgare Tarjan, 1964, della Florida. Tutte le popolazioni risultavano quasi identiche, dal punto di vista morfometrico, alle popolazioni tipo e a quelle di Sao Tome'. Le larve erano chiaramente distinte in quattro stadi di sviluppo. I profili di focalizzazione isoelettrica degli estratti dei campioni colorati per l'attivita' della superossido dismutasi mostravano due bande vicine a pH 7,6 e 7,6/7,3, rispettivamente. I prodotti della PCR della regione ITS erano fra 1 e 1,5 kb e venivano digeriti da sei enzimi di restrizione
We present the Herschel Gould Belt survey maps of the L1641 molecular clouds in Orion A. We extracted both the filaments and dense cores in the region. We identified which of dense sources are proto- ...or pre-stellar, and studied their association with the identified filaments. We find that although most (71%) of the pre-stellar sources are located on filaments there is still a significant fraction of sources not associated with such structures. We find that these two populations (on and off the identified filaments) have distinctly different mass distributions. The mass distribution of the sources on the filaments is found to peak at 4 Solar masses and drives the shape of the CMF at higher masses, which we fit with a power law of the form dN/dlogM \propto M^{-1.4+/-0.4}. The mass distribution of the sources off the filaments, on the other hand, peaks at 0.8 Solar masses and leads to a flattening of the CMF at masses lower than ~4 Solar masses. We postulate that this difference between the mass distributions is due to the higher proportion of gas that is available in the filaments, rather than in the diffuse cloud.
Context. G29.96-0.02 is a high-mass star-forming cloud observed at 70, 160, 250, 350, and 500 microns as part of the Herschel survey of the Galactic Plane during the Science Demonstration Phase. ...Aims. We wish to conduct a far-infrared study of the sources associated with this star-forming region by estimating their physical properties and evolutionary stage, and investigating the clump mass function, the star formation efficiency and rate in the cloud. Methods. We have identified the Hi-GAL sources associated with the cloud, searched for possible counterparts at centimeter and infrared wavelengths, fitted their spectral energy distribution and estimated their physical parameters. Results. A total of 198 sources have been detected in all 5 Hi-GAL bands, 117 of which are associated with 24 microns emission and 87 of which are not associated with 24 microns emission. We called the former sources 24 microns-bright and the latter ones 24 microns-dark. The 70-160 color of the 24 microns-dark sources is smaller than that of the 24 microns-bright ones. The 24 microns-dark sources have lower L_bol and L_bol/M_env than the 24 microns-bright ones for similar M_env, which suggests that they are in an earlier evolutionary phase. The G29-SFR cloud is associated with 10 NVSS sources and with extended centimeter continuum emission well correlated with the 70 microns emission. Most of the NVSS sources appear to be early B or late O-type stars. The most massive and luminous Hi-GAL sources in the cloud are located close to the G29-UC region, which suggests that there is a privileged area for massive star formation towards the center of the G29-SFR cloud. Almost all the Hi-GAL sources have masses well above the Jeans mass but only 5% have masses above the virial mass, which indicates that most of the sources are stable against gravitational collapse. The sources with M_env > M_virial and that ...
The presence of symptoms connected with the use of latex rubber gloves and sensitization to this allergen was studied in a group of 660 hospital workers who regularly used gloves as a means of ...protection. Symptoms connected with the use of gloves were reported by 153 subjects (23.2%) and were significantly associated with female subjects length of use and type of medical care. The majority of cases reported irritative symptoms (13.2%) whereas contact dermatitis and rash were reported by 3.6% and 5.5% of cases respectively. Systemic reactions (asthma and/or rhinitis) were reported by 5 subjects. Prick tests for latex were positive in 23 cases (3.5%), 15 of which were symptomatic. Positive skin reaction to latex was significantly associated with family atopy, personal case history and prick test. It is concluded that the presence of symptoms and sensitization to latex requires the implementation of preventive measures in order to reduce the risk of sensitization to a minimum, in addition to removal from exposure of those subjects who are already symptomatic or at risk.
The first Herschel Hi-Gal images of the galactic plane unveil the far-infrared diffuse emission of the interstellar medium with an unprecedented angular resolution and sensitivity. In this paper, we ...present the first analysis of these data in combination with that of Spitzer Glimpse & Mipsgal. We selected a relatively diffuse and low excitation region of the l~59\,^{\circ} Hi-Gal Science Demonstration Phase field to perform a pixel by pixel fitting of the 8 to 500 microns SED using the DustEM dust emission model. We derived maps of the Very Small Grains (VSG) and PAH abundances from the model. Our analysis allows us to illustrate that the Aromatic Infrared Bands (AIB) intensity does not trace necessarily the PAH abundance but rather the product of "abundance x column density x intensity of the exciting radiation field". We show that the spatial structure of PACS70microns map resembles the shorter wavelengths (e.g. IRAC8microns) maps, because they trace both the intensity of exciting radiation field and column density. We also show that the modeled VSG contribution to PACS70microns (PACS160microns) band intensity can be up to 50% (7%). The interpretation of diffuse emission spectra at these wavelengths must take stochastically heated particles into account. Finally, this preliminary study emphasizes the potential of analyzing the full dust SED sampled by Herschel and Spitzer data, with a physical dust model (DustEM) to reach the properties of the dust at simultaneously large and small scales.
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