Context. The Ne II line 12.81 μm was proposed to be a good tracer of gas in the environments of proto-planetary disks; its origin is explained by different mechanisms: jets in outflows, ...photo-evaporative disk winds driven by stellar X-rays/EUV or by the X-ray irradiated proto-planetary disk atmosphere. Previous Spitzer studies gave hints toward the neon emitting mechanism by exploring correlations between the line luminosity and properties of the star-disk system. These studies concluded that the origin of the emission is likely related to accretion and outflows, with some influence from X-rays. Aims. We provide direct constraints on the origin of the Ne II emission using high-spatial and spectral resolution observations that allow us to study the kinematics of the emitting gas. In addition we compare the Ne II line with optical forbidden lines. Methods. We obtained high-resolution ground-based observations with VISIR-VLT for 15 stars and UVES-VLT for three of them. The stars were chosen for having bright neon emission lines detected with Spitzer/IRS. The velocity shifts and profiles are used to disentangle the different emitting mechanisms producing the Ne II line. A comparison between results from this study and previous high-resolution studies is also presented. Results. The Ne II line was detected in seven stars, among them the first confirmed detection of Ne II in a Herbig Be star, V892 Tau. In four cases, the large blueshifted lines indicate an origin in a jet. In two stars, the small shifts and asymmetric profiles indicate an origin in a photo-evaporative wind. CoKu Tau 1, seen close to edge-on, shows a spatially unresolved line centered at the stellar rest velocity, although cross-dispersion centroids move within 10 AU from one side of the star to the other as a function of wavelength. The line profile is symmetric with wings extending up to ~±80 km s-1. The origin of the Ne II line is unclear and could either be due to the bipolar jet or to the disk. For the stars with VLT-UVES observations, in several cases, the optical forbidden line profiles and shifts are very similar to the profile of the Ne II line, suggesting that the lines are emitted in the same region. A general trend observed with VISIR is a lower line flux when compared with the fluxes obtained with Spitzer. We found no correlation between the line full-width at half maximum and the line peak velocity. The Ne II line remains undetected in a large part of the sample, an indication that the emission detected with Spitzer in those stars is likely extended.
Context
. Consistent modeling of protoplanetary disks requires the simultaneous solution of both continuum and line radiative transfer, heating and cooling balance between dust and gas and, of ...course, chemistry. Such models depend on panchromatic observations that can provide a complete description of the physical and chemical properties and energy balance of protoplanetary systems. Along these lines, we present a homogeneous, panchromatic collection of data on a sample of 85 T Tauri and Herbig Ae objects for which data cover a range from X-rays to centimeter wavelengths. Datasets consist of photometric measurements, spectra, along with results from the data analysis such as line fluxes from atomic and molecular transitions. Additional properties resulting from modeling of the sources such as disk mass and shape parameters, dust size, and polycyclic aromatic hydrocarbon (PAH) properties are also provided for completeness.
Aim
. The purpose of this data collection is to provide a solid base that can enable consistent modeling of the properties of protoplanetary disks. To this end, we performed an unbiased collection of publicly available data that were combined to homogeneous datasets adopting consistent criteria. Targets were selected based on both their properties and the availability of data.
Methods
. Data from more than 50 different telescopes and facilities were retrieved and combined in homogeneous datasets directly from public data archives or after being extracted from more than 100 published articles. X-ray data for a subset of 56 sources represent an exception as they were reduced from scratch and are presented here for the first time.
Results
. Compiled datasets, along with a subset of continuum and emission-line models are stored in a dedicated database and distributed through a publicly accessible online system. All datasets contain metadata descriptors that allow us to track them back to their original resources. The graphical user interface of the online system allows the user to visually inspect individual objects but also compare between datasets and models. It also offers to the user the possibility to download any of the stored data and metadata for further processing.
Context. Consistent modeling of protoplanetary disks requires the simultaneous solution of both continuum and line radiative transfer, heating and cooling balance between dust and gas and, of course, ...chemistry. Such models depend on panchromatic observations that can provide a complete description of the physical and chemical properties and energy balance of protoplanetary systems. Along these lines, we present a homogeneous, panchromatic collection of data on a sample of 85 T Tauri and Herbig Ae objects for which data cover a range from X-rays to centimeter wavelengths. Datasets consist of photometric measurements, spectra, along with results from the data analysis such as line fluxes from atomic and molecular transitions. Additional properties resulting from modeling of the sources such as disk mass and shape parameters, dust size, and polycyclic aromatic hydrocarbon (PAH) properties are also provided for completeness. Aim. The purpose of this data collection is to provide a solid base that can enable consistent modeling of the properties of protoplanetary disks. To this end, we performed an unbiased collection of publicly available data that were combined to homogeneous datasets adopting consistent criteria. Targets were selected based on both their properties and the availability of data. Methods. Data from more than 50 different telescopes and facilities were retrieved and combined in homogeneous datasets directly from public data archives or after being extracted from more than 100 published articles. X-ray data for a subset of 56 sources represent an exception as they were reduced from scratch and are presented here for the first time. Results. Compiled datasets, along with a subset of continuum and emission-line models are stored in a dedicated database and distributed through a publicly accessible online system. All datasets contain metadata descriptors that allow us to track them back to their original resources. The graphical user interface of the online system allows the user to visually inspect individual objects but also compare between datasets and models. It also offers to the user the possibility to download any of the stored data and metadata for further processing.
The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns.
A real-time RT-PCR assay was designed for the rapid ...screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing.
Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5–11 December, to 17.5% (25/143 samples) in the week 12–18, to 65.9% (89/135 samples) in the week 19–25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased from one in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons.
In conclusion, we designed an RT-qPCR assay capable to detect the Omicron variant, which can be successfully used for the purpose of wastewater-based epidemiology. We also described the history of the introduction and diffusion of the Omicron variant in the Italian population and territory, confirming the effectiveness of sewage monitoring as a powerful surveillance tool.
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•A real-time RT-PCR assay was designed for the rapid detection of the Omicron variant.•737 sewage samples collected throughout Italy (11 Nov – 25 Dec 2021) were tested.•The first occurrence of Omicron was on 7 December 2021, in Veneto, North Italy.•Omicron detection in sewage increased rapidly, raising from 1.0% to 65.9% in 3 weeks.•In the same period, the variant spread over the country, spreading from one Region to 17.
Dust amorphization in protoplanetary disks Glauser, A. M.; Güdel, M.; Watson, D. M. ...
Astronomy and astrophysics (Berlin),
12/2009, Letnik:
508, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Aims. High-energy irradiation of circumstellar material might impact the structure and the composition of a protoplanetary disk and hence the process of planet formation. In this paper, we present a ...study of the possible influence of stellar irradiation, indicated by X-ray emission, on the crystalline structure of circumstellar dust. Methods. The dust crystallinity is measured for 42 class II T Tauri stars in the Taurus star-forming region using a decomposition fit of the 10 μm silicate feature, measured with the spitzer IRS instrument. Since the sample includes objects with disks of various evolutionary stages, we further confine the target selection, using the age of the objects as a selection parameter. Results. We correlate the X-ray luminosity and the X-ray hardness of the central object with the crystalline mass fraction of the circumstellar dust and find a significant anti-correlation for 20 objects within an age range of approx. 1 to 4.5 Myr. We postulate that X-rays represent the stellar activity and consequently the energetic ions of the stellar winds which interact with the circumstellar disk. We show that the fluxes around 1 AU and ion energies of the present solar wind are sufficient to amorphize the upper layer of dust grains very efficiently, leading to an observable reduction of the crystalline mass fraction of the circumstellar, sub-micron sized dust. This effect could also erase other relations between crystallinity and disk/star parameters such as age or spectral type.
Abstract
Background
Sexual and gender minorities (SGM) are at higher risk for stigma, discrimination and, ultimately, development of risky health behaviours than heterosexual counterparts. Latest ...demographic data on SGM population in Italy date back to 2011 census. The prevalence of risk behaviours among SGM university students has not been previously estimated in Italy. We aimed at estimating the population of SGM university students and assessing the prevalence of risk behaviours.
Methods
We conducted a cross-sectional survey involving a sample of 18-25 years old students. Participants were asked to complete an anonymous, self-administrated questionnaire on sexual identity/orientation, smoking, use of condom and sexual partners in the last 24 months. χ2 tests were performed.
Results
We collected 9,988 questionnaires (response rate 91.3%); 1.41% did not disclose sexual orientation. Transgender individuals were 0.12%. Among cisgenders males, 95.39% identified as hetero-, 2.52% as homo- and 2.02% as bisexual; 94.50% of females as hetero-, 1.28% as homo- and 4.21% as bisexual. While among men the proportion of smokers was 30.7% without significant differences among subgroups (p=.219), this proportion was 26.1%, 40,5% and 51.6% among hetero-, homo- and bisexual women (p<.001); 62.4% of all males declared to use the condom without significant differences (p=.089), but 19.0% of homo- and 43.4% of bi- females did compared with 55.5% of heterosexual (p<.001); 18,7% of hetero-, 49.4% of homo- and 32.4% of bisexual men declared to have had three or more partners (p<.001); among hetero- women the proportion was 11.1%, while 12.5% and 26.3% among homo- and bisexuals.
Conclusions
SGMs were 5.26% of university students. Compared with hetero- counterparts, homo- and bisexual women showed a higher prevalence of all risk behaviours investigated. In contrast, homo- and bisexual men showed a similar behaviours compared with heterosexual men, except for a significantly higher number of partners.
Key messages
Sexual and gender minorities (SGMs) account for 5.26% of the investigated university student population; 4.54% of cisgender men and 5.49% of cisgender women are homo- or bisexual; trans are 0.12%. SGMs show unhealthier behaviours compared with heterosexual counterparts; in particular, bisexual women show higher prevalence of smoking and non-use of the condom.
Tetanus is a non-communicable disease, preventable with vaccination. Despite the implemented vaccination strategy, a certain number of tetanus cases per year continue to occur. The aim of the study ...was to evaluate the seroprevalence of anti-tetanus antibodies in the Italian population by age, sex and geographical area.
To determine the level of tetanus-specific antibodies, an immunoenzymatic assay was used.
A total of 3,821 serum samples were collected in the years 2019–20 from healthy subjects aged 6–90 years residing in 13 Italian regions. Overall, 85 % of the tested subjects resulted positive. The rate of subjects protected against tetanus showed a gradual decrease from the younger age groups to the older ones (6–12 years: 93.6 %, 13–24 years: 91.8 %, 25–39 years: 91.0 %, 40–64 years: 78.2 %, ≥ 65 years: 45.3 %); this is particularly evident in the Southern regions and Islands. Moreover, the prevalence of subjects with low protection (<0.1 IU/ml) was significantly higher in the ≥ 65 age group (10.3 %). Males and females’ prevalence showed a significant difference only in the oldest age group (M: 60.8 %, F: 30.4 %). In general, a higher prevalence was observed for Northern (90.8 %) and Central regions (87.3 %) than Southern regions and Islands (80.0 %).
These data, compared with epidemiological ones which showed a high number of cases in the elderly, confirmed that the population with lower protection has a greater risk of contracting the disease, demonstrating the need for adequate immunization through both primary vaccination and boosters for all ages and both sexes, in order to provide lifelong protection.
Abstract
HPV vaccination is a milestone in primary prevention. However in Italy, vaccine coverage is still nowhere near the target of 95%. We investigated drivers of vaccine uptake among university ...students, as they are likely to have just assumed a central role in their healthcare decision-making and potential barriers may differ from parents.
University students aged 18-25 were asked to fill in a questionnaire. The effect of socio-demographic and behavioural characteristics on HPV awareness was assessed with a logistic regression adjusting for age, gender, nationality, degree course, relationship, age at first intercourse, number of sexual partners, smoking, sexual orientation, past diagnosis of STDs and knowledge of people who had received HPV vaccine. A second regression adjusting also for information sources, awareness and knowledge investigated drivers of vaccine uptake.
9,988 questionnaires were included; awareness of HPV and vaccine was 83.3% and 69.9%, respectively. Awareness (adjOR: 3.3 95%CI 2.3-4.6) and a good knowledge positively affected acceptability, as well as a previous diagnosis of STDs and knowledge of vaccinated people. Healthcare workers (adjOR 1.6 95%CI 1.4-1.9) and family members (adjOR 1.7 95%CI 1.4-2.1) were the most influencing information sources, even if knowledge of vaccinated people was by far more persuasive (adjOR 2.7 95%CI 2.2-3.3). Only 12% of participants were acquainted with skin to skin HPV transmission, while 75% believed in a full effectiveness of condom; less than 22% associated HPV with cancer (other than cervical cancer).
Efforts to increase awareness are likely to be worth considering that: awareness is the main determinant of vaccine uptake; only 50% of individuals not interested in receiving vaccine were aware of it; males are much less aware (adjOR 0.09 95%CI 0.07-0.11). Moreover, this study spotlights some misconceptions and may provide suitable evidence in tailoring more efficacious communication strategies.
Key messages
There is room for improving the awareness of HPV. Efforts are likely to be worth since it remains the main determinant of vaccine uptake. Awareness has been growing but a gender gap still persists.
Communication should focus more on HPV involvement in neoplasia other than cervical cancer; transmission via skin to skin contact; multiple sex partnership; partial protection of condom.
![On the origin of [Ne II] em...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0004-6361/small "On the origin of [Ne II] emission in young stars: mid-infrared and optical observations with the Very Large Telescope")
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