60 research outputs found
Contribution of soft-bodied meiofaunal taxa to Italian marine biodiversity
Meiofauna includes an astonishing diversity of organisms, whose census is far from being complete. Most classic
ecological studies have focused on hard-bodied Ecdysozoan taxa (notably Copepoda and Nematoda), whose cuticle
allows determination at species-level after fixation, rather than soft-bodied, Spiralian taxa, which most often lose any
diagnostic feature in fixed samples. Yet, metabarcoding studies have recently revealed a species-richness of softbodied taxa comparable, and in cases superior, to that of Copepoda and Nematoda together. However, given
objective difficulties inherent to their study, which necessarily has to be performed on living individuals, and their
limited utilisation for ecological and applicative research, taxonomic expertise on soft-bodied organisms has declined
over the years, and diversity of these phyla in most areas of the world is presently completely unknown. Here we
present an expert-based survey of current knowledge on the composition and distribution of soft-bodied meiofaunal
taxa in Italy, with special references to the predominantly or exclusively meiobenthic phyla Gastrotricha,
Gnathostomulida, Platyhelminthes, Rotifera, Xenacoelomorpha, and macrofaunal taxa with conspicuous meiofaunal
representatives (Annelida, Mollusca and Nemertea). A total of 638 described species have been reported from
Italian coasts; furthermore, the existence of a large number of undescribed species is mentioned. Knowledge of
Annelida, Gastrotricha, and Rotifera appears particularly detailed, placing Italy among the best-known country
worldwide. In contrast, knowledge of Platyhelminthes and Xenacoelomorpha appears patchy, and limited to few
areas. Sampling effort has been uneven, with most species recorded from the Tyrrhenian Sea, while large sections of
the Adriatic and Ionian seas have been poorly explored. Results highlight the role that Marine Biological Stations,
notably the Zoological Station “Anton Dohrn” in Naples, have had in promoting the study of soft-bodied taxa in
Ital
The Yellow Excitonic Series of Cu2O Revisited by Lyman Spectroscopy
We report on the observation of the yellow exciton Lyman series up to the
fourth term in Cu2O by time-resolved mid-infrared spectroscopy. The dependence
of the oscillator strength on the principal quantum number n can be well
reproduced using the hydrogenic model including an AC dielectric constant, and
precise information on the electronic structure of the 1s exciton state can be
obtained. A Bohr radius a_{1s}=7.9 A and a 1s-2p transition dipole moment
\mu_{1s-2p}= 4.2 eA were found
Frictional Drag between Two Dilute Two-Dimensional Hole Layers
We report drag measurements on dilute double layer two-dimensional hole
systems in the regime of r_s=19~39. We observed a strong enhancement of the
drag over the simple Boltzmann calculations of Coulomb interaction, and
deviations from the T^2 dependence which cannot be explained by
phonon-mediated, plasmon-enhanced, or disorder-related processes. We suggest
that this deviation results from interaction effects in the dilute regime.Comment: 4 pages, 3 figures, accepted in Phys. Rev. Lett. Added single layer
transport dat
Positive selection on panpulmonate mitogenomes provide new clues on adaptations to terrestrial life
Anaplasmose in einem Milchviehbetrieb in Graubünden: Epidemiologische Ausbruchsuntersuchung
In summer of 2002, a case of severe clinical bovine anaplasmosis caused great losses in a dairy farm of an animal trader in Grisons. This article outlines the general approach of an outbreak investigation considering the case of anaplasmosis as an example. The goals of such investigations are to identify and eliminate the source of a disease outbreak in order to avoid additional cases. In addition, recommendations should be developed for preventing or limiting the magnitude of similar outbreaks in the future. In the outbreak presented, the causative agents were probably brought into the dairy farm by animal trade. Due to the large herd size, a missing quarantine for new animals and the coinfection with several pathogens, this case led to a high number of fatalities. The investigations of this outbreak demonstrated the importance of an universal and consistent identification of individual animals for the reconstruction of their movements. The veterinary practitioner should be reminded to act cautiously when facing strange clinical cases and to also consider "exotic diseases" as a possible cause
Individual versus standard quality of life assessment in a phase II clinical trial in mesothelioma patients: feasibility and responsiveness to clinical changes
BACKGROUND: In patients with malignant pleural mesothelioma undergoing a multimodality therapy, treatment toxicity may outweigh the benefit of progression-free survival. The subjective experience across different treatment phases is an important clinical outcome. This study compares a standard with an individual quality of life (QoL) measure used in a multi-center phase II trial. PATIENTS AND METHODS: Sixty-one patients with stage I-III technically operable pleural mesothelioma were treated with preoperative chemotherapy, followed by pleuropneumonectomy and subsequent radiotherapy. QoL was assessed at baseline, at day 1 of cycle 3, and 1, 3 and 6 months post-surgery by using the Rotterdam Symptom Checklist (RSCL) and the Schedule for the Evaluation of Quality of Life-Direct Weighting (SEIQoL-DW), a measure that is based on five individually nominated and weighted QoL-domains. RESULTS: Completion rates were 98% (RSCL) and 92% (SEIQoL) at baseline and 98%/89% at cycle 3, respectively. Of the operated patients (N=45) RSCL and SEIQoL were available from 86%/72%, 93%/74%, and 94%/76% at months 1, 3, and 6 post-surgery. Average assessment time for the SEIQoL was 24min compared to 8min needed for the RSCL. Median changes from baseline indicate that both RSCL QoL overall score and SEIQoL index remained stable during chemotherapy with a clinically significant deterioration (change>or=8 points) 1 month after surgery (median change of -66 and -14 for RSCL and SEIQoL, respectively). RSCL QoL overall scores improved thereafter, but remained beneath baseline level until 6 months after surgery. SEIQoL scores improved to baseline-level at month 3 after surgery, but worsened again at month 6. RSCL QoL overall score and SEIQoL index were moderately correlated at baseline (r=.30; p<or=.05) and at 6-month follow-up (r=.42; p<or=.05) but not at the other time points. CONCLUSION: The SEIQoL assessment seems to be feasible within a phase II clinical trial, but may require more effort from staff. More distinctive QoL changes in accordance with clinical changes were measured with the RSCL. Our findings suggest that the two measures are not interchangeable: the RSCL is to favor when mainly information related to the course of disease- and treatment is of interest
Exploring the Diversity of Mesopsammic Gastropods: How to Collect, Identify, and Delimitate Small and Elusive Sea Slugs? *
Hydrological features above a Southern Ocean seamount inhibit larval dispersal and promote speciation: evidence from the bathyal mytilid Dacrydium alleni sp. nov. (Mytilidae: Bivalvia)
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