811 research outputs found

    HST and ground-based eclipse observations of V2051 Ophiuchi: Binary parameters

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    We report on high-speed eclipse photometry of the dwarf nova V2051 Oph while it was in a low brightness state, at B ~ 16.2 mag. In comparison to the average IUE spectra, the ultraviolet continuum and emission lines appear reduced by factors of, respectively, ~4 and ~5. Flickering activity is mostly suppressed and the lightcurve shows the eclipse of a compact white dwarf at disc centre which contributes ~60 per cent of the total light at 3900--4300 A. We use measurements of contact phases in the eclipse lightcurve to derive the binary geometry and to estimate masses and relevant dimensions. We find a mass ratio of q= 0.19+/-0.03 and an inclination of i= 83+/-2 degrees. The masses of the component stars are M_1 = 0.78+/-0.06 M_dot and M_2 = 0.15+/-0.03 M_dot. Our photometric model predicts K_1 = 83+/-12 km/s and K_2= 435+/-11 km/s. The predicted value of K_1 is in accordance with the velocity amplitude obtained from the emission lines after a correction for asymmetric line emission in the disc is made (Watts et al. 1986). The secondary of V2051 Oph is significantly more massive than the secondaries of the other ultra-short period dwarf novae. V2051 Oph is probably a relatively young system, whose secondary star had not enough time to evolve out of thermal equilibrium.Comment: 16 pages, 7 postscript figures, coded using MNRAS latex style. To appear in Monthly Notices of the Royal Astronomical Society. Revised version with changes in section 4.3. For related papers and files see ftp://fsc01.fsc.ufsc.br/pub/bap and http://www.fsc.ufsc.br/~astr

    Multiproxy archaeological investigation and Garden Archaeology in the Charterhouse of Calci (Tuscany, central Italy) and its territory: results and research data

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    A wide-ranging archaeological research programme at the Charterhouse and in the broader area of the Municipality of Calci has been performed since 2018. The archaeological research included the collection of legacy and aerial archaeology data, invasive and non-invasive investigations, as well as natural scientific analysis in the monastic complex. Special attention was paid to the archaeological investigations of three different monks’ cells gardens (the Prior’s, the Apothecary’s, and the Master’s), and stratigraphic excavations were combined with archeozoological and archaeobotanical analyses to define the horticultural practices implemented over the centuries of occupation of the Charterhouse. Among the three case studies, the most representative is the Prior’s meditation garden, where the excavation explored the phases prior to the construction of the building (14th century), the 18th-century renovation in the current form, and its abandonment at the end of the 20th century. Pollen analysis has allowed to reconstruct the richness of herbal species characterising an ever-blooming garden, with flowers and ornamental plants, such as roses, lilac, and water lilies, and also vegetables. According to charcoal and fruit-remain analyses, the Charterhouse exploited local hilly woods, satisfying the requirements of fuel by maquis and thermophilous deciduous forest. The agricultural practices included the cultivation of fruit trees, such as chestnut, olive, almond, and vine. Finally, archaeozoological analysis attests the domestic cat as the most frequent taxon in all contexts, probably common in the monastery as a pet and cell companion. This paper presents an overview and a discussion of the results of the investigations conducted and the complete archaeological dataset

    Non-spatial skills differ in the front and rear peri-personal space

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    In measuring behavioural and pupillary responses to auditory oddball stimuli delivered in the front and rear peri-personal space, we find that pupils dilate in response to rare stimuli, both target and distracters. Dilation in response to targets is stronger than the response to distracters, implying a task relevance effect on pupil responses. Crucially, pupil dilation in response to targets is also selectively modulated by the location of sound sources: stronger in the front than in the rear peri-personal space, in spite of matching behavioural performance. This supports the concept that even non-spatial skills, such as the ability to alert in response to behaviourally relevant events, are differentially engaged across subregions of the peri-personal space

    Global radiant flux from active volcanoes: the 2000–2019 MIROVA database

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    Since 2000, the Moderate Resolution Imaging Spectroradiometer (MODIS) has acquired infrared images of the Earth’s surface daily. These data have made it possible to measure the thermal energy radiated by the world’s most famous volcanoes and also to discover and track eruptions in remote and poorly monitored regions. In this work, we present the database of Volcanic Radiative Power (VRP, in W) time series, recorded by the MIROVA (Middle Infrared Observation of Volcanic Activity) system over 2 decades of MODIS observations (2000–2019) at 111 active volcanoes. The database reveals that globally, the number of thermally active volcanoes each year varies between 60 and 80, almost equally partitioned between volcanoes with a basic (50%) and intermediate (45%) composition, while only 5% is represented by volcanoes erupting acidic lavas. Within the investigated period, the global-scale heat flux was almost stationary, and occasionally punctuated by peaks associated with the largest effusive eruptions (e.g., Bardarbunga and Kilauea). The Volcanic Radiative Energy (VRE, in J) emitted by basic volcanoes (~1.8 × 1018 J) in 20 years constitutes 91% of the total, while intermediates and acids contribute only 8% (~1.8 × 1017 J) and 1% (~1.7 × 1016 J), respectively. A comparison with the volume of lava erupted effusively by the same volcanoes reveals that this difference is attributed to the lower efficiency in radiating thermal energy of increasingly acidic (viscous) lava bodies. Each compositional group is associated with a specific relationship between VRE and erupted volume which characterises most of the effusive volcanoes. On the other hand, some open-vent volcanoes reveal that much more heat is released than that theoretically radiated by the erupted lava. This imbalance (hereby called excess radiation) is attributed to an additional heat source, likely associated with an underlying convective magma column and/or to outgassing through a permeable conduit. We are convinced that the database presented in this work will be useful to support new emerging studies on globalscale volcanism and will contribute to a better understanding of each volcanic system

    A systematic review and meta-analysis on early-childhood-caries global data.

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    OBJECTIVES The present study systematically reviewed and provided a meta-analysis on early childhood caries (ECC) global prevalence and its association with socioeconomic indicators, both geographical and regarding unemployment rate, national income as well as income inequalities. METHODS Only cross-sectional or cohort studies covering ECC prevalence and experience in children younger than 71 months, reporting sample size, diagnostic criteria and conducted in urban and rural communities were considered. No language restriction was selected. Studies published from 2011 to 2022 available in PubMed, Web of Science, Embase and Open Grey literature were retrieved by ad hoc prepared search strings. The meta-analyses were conducted for both overall ECC prevalence and experience stratified by country of publication as well as measures of socioeconomic indicators using a random effects model using STATA 18®. RESULTS One hundred publications reporting ECC data from 49 countries (published from 2011 to 2022) were included and summarized by meta-analysis. The lowest prevalence was reported in Japan (20.6%) and Greece (19.3%). The global estimated random-effect pooled prevalence of ECC was 49% (95%CI: 0.44-0.55). The random-effect pooled caries prevalence (ECC) was 34% (95%CI: 02.20-0.48) (Central/South America), 36% (95%CI: 0.25-0.47) (Europe), 42% (95%CI: 0.32-0.53) (Africa), 52% (95%CI: 0.45-0.60) (Asia-Oceania), 57% (95%CI: 0.36-0.77) (North America) and 72% (95%CI: 0.58-0.85) (Middle East). When stratified by gross national income (GNI) the ECC prevalence ranged from 30% (20,00020,000-39,999) to 57% in countries with the lowest GNI (<$5000). Stratification by inequality index (Gini index) resulted in an ECC prevalence range of 39% (low inequality) to 62% (no inequality), while for life expectancy the ECC prevalence ranged from 28% in countries with the highest life expectancy (< 80 years) to 62% in countries with 71-75 years life expectancy. DISCUSSION Within the limitations of this study (lack of certainty about the results as many countries are not represented and lack of uniformity in prevalence and experience data represented), results from 49 different countries reported a wide range of ECC prevalence. These reports indicated persisting high worldwide distribution of the disease. Both ECC prevalence and experience were associated with geographical areas and GNI. REGISTRATION PROSPERO: CRD-42,022,290,418

    Development of antigen-specific ELISA for circulating autoantibodies to extracellular matrix protein 1 in lichen sclerosus

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    Lichen sclerosus is a common, acquired chronic inflammatory skin disease of unknown etiology, although circulating autoantibodies to the glycoprotein extracellular matrix protein 1 (ECM1) have been detected in most patients’ sera. We have examined the nature of ECM1 epitopes in lichen sclerosus sera, developed an ELISA system for serologic diagnosis, and assessed clinicopathological correlation between ELISA titer and disease. Epitope-mapping studies revealed that lichen sclerosus sera most frequently recognized the distal second tandem repeat domain and carboxyl-terminus of ECM1. We analyzed serum autoantibody reactivity against this immunodominant epitope in 413 individuals (95 subjects with lichen sclerosus, 161 normal control subjects, and 157 subjects with other autoimmune basement membrane or sclerosing diseases). The ELISA assay was highly sensitive; 76 of 95 lichen sclerosus patients (80.0%) exhibited IgG reactivity. It was also highly specific (93.7%) in discriminating between lichen sclerosus and other disease/control sera. Higher anti-ECM1 titers also correlated with more longstanding and refractory disease and cases complicated by squamous cell carcinoma. Furthermore, passive transfer of affinity-purified patient IgG reproduced some histologic and immunopathologic features of lichen sclerosus skin. This new ELISA is valuable for the accurate detection and quantification of anti-ECM1 autoantibodies. Moreover, the values may have clinical significance in patients with lichen sclerosus

    Do best-selected strains perform table olive fermentation better than undefined biodiverse starters? A comparative study

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    Twenty-seven Lactobacillus pentosus strains, and the undefined starter for table olives from which they were isolated, were characterised for their technological properties: tolerance to low temperature, high salt concentration, alkaline pH, and olive leaf extract; acidifying ability; oleuropein degradation; hydrogen peroxide and lactic acid production. Two strains with appropriate technological properties were selected. Then, table olive fermentation in vats, with the original starter, the selected strains, and without starter (spontaneous fermentation) were compared. Starters affected some texture profile parameters. The undefined culture resulted in the most effective Enterobacteriaceae reduction, acidification and olive debittering, while the selected strains batch showed the lowest antioxidant activity. Our results show that the best candidate strains cannot guarantee better fermentation performance than the undefined biodiverse mix from which they originate

    Topical application of chlorhexidine gel with brush-on technique in the tailored treatment of plaque induced gingivitis

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    Aim: This study aimed to assess the action of a chlorhexidine-based brush-on gel application in the treatment of plaque-related gingivitis. Methods: The enrollment involved consecutive patients diagnosed with plaque-induced gingivitis. Each participant's full mouth plaque score and gingival index were recorded at the first appointment (t0) and at follow ups after 1 week (t1), 2 weeks (t2) and 3 weeks (t4). All patients were randomly sorted into two groups: A study group, who was given instruction to brush their gums daily with a chlorhexidine gel, and a control group who received a placebo gel. The two groups' data at baseline were compared using a chi-square test, while the t-Student and Mann-Whitney tests were employed to analyze the index's trends, both separately and compared. Results: In total, 30 patients were enrolled, 15 referring to the study group and 15 to the control group. The study group had an 87% decrease in their plaque score and an 84% decrease in their gingival index (p &lt; 0.05). The control group displayed a reduction in plaque score and gingival index of 74% and 84%, respectively (p &lt; 0.05). The plaque score decreased statistically more significantly in the study group than in the control group. Conclusion: Topical employment of a chlorhexidine-containing brush-on gel appears to be a useful home tool in the treatment of plaque-induced gingivitis, associated with professional debridement
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