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The original description of the fan worm Parasabella fullo (Grube, 1878) is brief and mainly focused on the color. This paper provides a redescription based on syntype material from northern Japan kept at Museum für Naturkunde of Berlin and new records in California (USA). Diagnostic characters used in redescribing the species are the shapes of inferior thoracic notochaetae, ventral thoracic shields and dorsal collar margins. Although this Japanese species was collected on vessels' hulls in California, it is not clear if and where the species is established here, due to past difficulties in identification without well-defined characters. Nevertheless, a resident population appears to exist in the region, given the species occurrence on local recreational vessels. The redescription provides information to distinguish it from the local Californian indigenous species Parasabella pallida Moore, 1923. [ABSTRACT FROM AUTHOR]

Crystals of pyroxene are common in meteorites but few compositions have been recognized in astronomical environments due to the limited chemistries included in laboratory studies. We present quantitative room-temperature spectra of 17 Mg-, Fe-, and Ca-bearing ortho- and clinopyroxenes, and a Ca-pyroxenoid in order to discern trends indicative of crystal structure and a wide range of composition. Data are produced using a diamond anvil cell: our band strengths are up to six times higher than those measured in KBr or polyethylene dispersions, which include variations in path length (from grain size) and surface reflections that are not addressed in data processing. Pyroxenes have varied spectra: only two bands, at 10.22  and 15.34  μ m in enstatite (En99), are common to all. Peak wavelengths generally increase as Mg is replaced by Ca or Fe. However, two bands in MgFe-pyroxenes shift to shorter wavelengths as the Fe component increases from 0 to 60 per cent. A high-intensity band shifts from 11.6 to 11.2  μ m and remains at 11.2  μ m as Fe increases to 100 per cent; it resembles an astronomical feature normally identified with olivine or forsterite. The distinctive pyroxene bands between 13  and 16  μ m show promise for their identification in Mid-Infrared-Instrument spectra obtained with the James Webb Space Telescope. The many pyroxene bands between 40 and 80  μ m could be diagnositic of silicate mineralogy if data were obtained with the proposed Space Infrared Telescope for Cosmology and Astrophysics. Our data indicate that comparison between room-temperature laboratory bands for enstatite and cold ∼10 − K astronomical dust features at wavelengths |$\gtrsim 28~\mu$| m can result in the identification of (Mg,Fe)- pyroxenes that contain 7–15 per cent less Fe– than their true values because some temperature shifts mimic some compositional shifts. Therefore some astronomical silicates may contain more Fe, and less Mg, than previously thought. [ABSTRACT FROM AUTHOR]

1 - The Long-Term Ecosystem Research (LTER) network, now a global reality, was founded on a combination of long-term ecological studies, short-term experiments, and comparisons among sites and eco-domains. 2 - The LTER-Italy network was officially established as a formal member of the LTER international network in 2006, following a wider on-going process in Europe; it currently consists of 22 sites representing the main ecosystem typologies of Italy. Four coastal transitional ecosystem sites are included in the LTER-Italy network: on the northern Peninsula, these include the Venice Lagoon and the lagoons of the Po River Delta, which are characterized by a temperate climate and the influence of t ides; and in the southern sector, these include the coastal ecosystems of Sardinia and the Mar Piccolo of Taranto, which are characterized by a Mediterranean climate and the absence of sensible tides. 3 - In this paper, we present and discuss three main issues: (1) the LTER-International and LTER-Europe context, emphasising the most practical issues and activities that must be addressed for the effective organization and maintenance of LTER networks; (2) the history, structure, and perspectives of the national LTER-Italy network; and (3) the opportunities, strengths, and weaknesses related to participation of the LTER-Italy network in the study of coastal transitional ecosystems. [ABSTRACT FROM AUTHOR]

Oxide and sulphide minerals are expected to occur in diverse astronomical environments. However, optical constants for such minerals are either lacking or poorly characterized. Minimizing errors in laboratory data, while extrapolating over wide frequency ranges, is the focus of this report. We present reflection and absorption spectra of single-crystal MgO from about ∼100 to 18 000 cm−1 (∼100 to 0.5 μm), and derive emissivity, dielectric and optical functions ( n and k) using classical dispersion analysis and supplementary data to ensure that the reflectivity values are correct at the low- and high-frequency limits. Absorbance spectra of thin films of oxides (MgO, CaO, FeO and ZnO) and sulphides (MgS, CaS and FeS) are in good agreement with available reflectivity measurements, and provide information on the various effects of chemical composition, structure and optical depth. The greatest mismatch occurs for MgO, connected with this compound having the broadest peak in reflectance. The ferrous compounds (FeO and FeS) have relatively weak infrared features and may be difficult to detect in astronomical environments. Previous optical data based on transmission spectra of dispersions have underestimated the strength of the main infrared features because this approach includes spectral artefacts that arise from the presence of opaque particulates, or from non-uniform optical depth. We show that areal coverage, not grain size, is the key factor in altering absorption spectra from the intrinsic values, and discuss how to account for ‘light leakage’ in interpreting astronomical data. Previous reflectivity data on polycrystals differ from intrinsic values because of the presence of additional, internal reflections, creating errors in the derived optical functions. We use classical dispersion analysis and supplemental data from optical microscopy to provide correct n- and k-values for FeO from the far-infrared to the visible, which can then be used in radiative transfer models. Thin-film absorption data are also affected by internal reflections in the transparent regions: we show how to recognize these features and how to obtain the absorption coefficient, n, and k from thin-film infrared data on CaO, CaS and MgS using the damped harmonic oscillator model. [ABSTRACT FROM AUTHOR]