9 research outputs found

    Effects of human impacts on diversity and distribution of chironomids (Diptera: Chironomidae) in prealpine springs

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    Diversity and distribution of chironomid fauna (Diptera: Chironomidae) in 36 springs in the Italian Prealps (Veneto and Trentino NE-Italy, 46°N, 10-11°E) was studied in relation to altitude, spring type and grade of disturbance. The springs were located between 62 and 1710 m asl of altitude, in three calcareous mountain areas (Mt. Baldo, Mts. Lessini and Mt. Pasubio). They differed in conservation status (natural, moderately and highly disturbed) and belonged to five hydromorphological types (rheocrene, limnocrene, rheohelocrene, rheolimnocrene, rheohygropetric). Each spring was surveyed once, between early summer and autumn, within 50 m of the spring’s source (eucrenal). A total of 4198 chironomid larvae and pupae were sorted from 111 macroinvertebrate samples collected, belonging to five subfamilies (Tanypodinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae), 41 genera and 60 species/groups of species, and three juveniles taxa. As expected, Orthocladiinae accounted for a large part of specimens (88%) and species (74%), with Tvetenia calvescens/bavarica as the most frequent and abundant taxon, shared by pristine and disturbed springs and by all spring types. Most taxa were found in few sites, and frequencies declined gradually for most wider distributed species. A high number (74%) of rare (= present in less than 10% of sites) taxa were found and from one to 23 taxa were identified per spring. Maximum richness occurred in moderately disturbed (Shannon-H = 1.29±0.60) springs, located at medium-high altitude (385-1266 m asl), according to the intermediate disturbance hypothesis. Even the evenness (Equitability-J) was higher as average in these springs. A Cluster Analysis run on Bray-Curtis similarity index highlighted a high similarity i) between the chironomid assemblages of moderately disturbed and natural springs (44 species in each spring group, with 29 species in common), and ii) between rheocrene and rheohelocrene types, thus the springs with the highest microhabitat heterogeneity. High individuality of springs was revealed, and new information about non-biting midges autecology provided. The utility of chironomids as bioindicators of water quality and ecological state of springs was confirmed, with some species e associated with high disturbance level (e.g., Polypedilum nubeculosum gr. to water intake works) and others with pristine conditions (e.g., Pseudodiamesa branickii)

    Two subsets of stem-like CD8+ memory T cell progenitors with distinct fate commitments in humans

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    T cell memory relies on the generation of antigen-specific progenitors with stem-like properties. However, the identity of these progenitors has remained unclear, precluding a full understanding of the differentiation trajectories that underpin the heterogeneity of antigen-experienced T cells. We used a systematic approach guided by single-cell RNA-sequencing data to map the organizational structure of the human CD8+ memory T cell pool under physiological conditions. We identified two previously unrecognized subsets of clonally, epigenetically, functionally, phenotypically and transcriptionally distinct stem-like CD8+ memory T cells. Progenitors lacking the inhibitory receptors programmed death-1 (PD-1) and T cell immunoreceptor with Ig and ITIM domains (TIGIT) were committed to a functional lineage, whereas progenitors expressing PD-1 and TIGIT were committed to a dysfunctional, exhausted-like lineage. Collectively, these data reveal the existence of parallel differentiation programs in the human CD8+ memory T cell pool, with potentially broad implications for the development of immunotherapies and vaccines

    Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

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    Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

    Storiografia e uso pubblico del grande brigantaggio nell'Italia repubblicana

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    Storia e storigrafia del "grande brigantaggio" dall'Unità a oggi. Il libro tratta della letteratura storica , delle narrazioni e dell'uso pubblico del cosiddetto "grande brigantaggio" verificatosi nel corso del processo di unificazione e nei primi anni del Regno d'Italia, attraverso diversi approcci metodologici , da quelli storico politici a quelli militari, letterari e antropologici. Si affronta anche l'uso del tema nel secondo dopoguerra e nel corso del sec. XXI, incluse le forme narrative adottate dal cosiddetto "neoborbonismo"

    K/Ka-Band Very High Data-Rate Receivers: A Viable Solution for Future Moon Exploration Missions

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    This paper presents a feasibility study for a very high data rate receiver operating in the K/Ka-band suitable to future Moon exploration missions. The receiver specifications are outlined starting from the mission scenario and from a careful system analysis. The designed architecture uses a low noise front-end to down-convert the incoming K/Ka-band signal into a 3.7 GHz intermediate frequency (IF). For maximum flexibility, a software defined radio (SDR) is adopted for the I/Q demodulation and for the analog to digital conversion (ADC). The decoding operations and the data interface are carried out by a processor based on field programmable gate array (FPGA) circuits. To experimentally verify the above concepts, a preliminary front-end breadboard is implemented, operating between 27.5 and 30 GHz. The breadboard, which uses components off the shelf (COTS) and evaluation boards (EVBs), is characterized by a 46 dB gain, a 3.4 dB noise figure and a − 37 dBm input-referred 1 dB compression point. Finally, a 40 Msym / s quadrature phase shift keying (QPSK) signal is demodulated by means of a commercially available SDR, demonstrating the above concept. The importance of these results is that they have been obtained exploiting a class of miniaturized and low cost microwave integrated circuits currently available on the market, opening the way to a dense communication infrastructure on cislunar space

    Acute Delta Hepatitis in Italy spanning three decades (1991-2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

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