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The status and movements of barbel Barbus barbus was assessed in a by-passed section of the former course of the Lower River Lee (England), which is amongst the most densely populated river catchments in England. Barbel abundance data from historical fisheries surveys and data on the movements of eleven tagged barbel between this section and the adjacent navigable channel using acoustic telemetry between November 2005 and November 2006 were examined. A popular area for anglers, the study stretch suffered a release of pollution (of unknown origin or type) in April 2006, approximately half way through the study. Contrary to unconfirmed reports of mass mortalities, the number of dead fish observed by the Environment Agency was low and none of the tagged fish died during or after the pollution incident. The historical survey data revealed a progressive decline in barbel abundance from the 1970s, through the 1990s, and up to 2009, suggesting that the pollution incident of April 2006 served to exacerbate an on-going, progressive decline in the species' abundance in this sector of the Old River Lee. The tagged barbel demonstrated great fidelity to one part of the study stretch, covered by a single acoustic receiver, including during the pollution event for some tagged barbel. This reluctance of barbel to leave their home area, even under altered conditions, suggests that this stretch of the River Lee satisfies all day-to-day requirements of the fish and provides refuge, at least for some fish, during adverse conditions.

The transition from the gabbroic oceanic crust to the residual mantle harzburgites of the Oman ophiolite has been drilled at Holes CM1A and CM2B (Wadi Tayin massif) during Phase 2 of the International Continental Scientific Drilling Program Oman Drilling Project (November 2017–January 2018). In order to unravel the formation processes of ultramafic rocks in the Wadi Tayin massif crust‐mantle transition zone and deeper in the mantle sections beneath oceanic spreading centers, our study focuses on the whole rock major and trace element compositions (together with CO2and H2O concentrations) of these ultramafic rocks (56 dunites and 49 harzburgites). Despite extensive serpentinization and some carbonation, most of the trace element contents (REE, HFSE, Ti, Th, U) record high temperature, magmatic process‐related signatures. Two major trends are observed, with good correlations between (a) Th and U, Nb and LREE on one hand, and between (b) heavy REE, Ti and Hf on the other hand. We interpret the first trend as the signature of late melt/peridotite interactions as LREE are known to be mobilized by such processes (‘‘lithospheric process’’) and the second trend as the signature of the initial mantle partial melting (‘‘asthenospheric process’’), with little or no overprint from melt/rock reaction events. We focus on the transition from the oceanic crust to the Earth's mantle by studying Holes CM1A and CM2B, drilled in the Oman ophiolite during Phase 2 of the International Continental Scientific Drilling Program Oman Drilling Project. Despite extensive serpentinization and some carbonation, the dunites and harzburgites from the transition zone and the mantle section show a large variability in their petrological and chemical compositions. Results indicate that most of the trace element contents (REE, HFSE, Ti, Th, U) record high temperature, magmatic process‐related signatures. Two major trends are observed, with good correlations between (a) Th and U, Nb and LREE on one hand, and between (b) heavy REE, Ti and Hf on the other hand. We interpret the first trend as the signature of late interactions between a percolating melt and the harzburgites and/or dunites, and the second trend as the signature of the initial mantle partial melting, with little or no overprint from melt/rock reaction events. The transition from the oceanic crust to the mantle of Oman has been drilled in the crust‐mantle Holes during Phase 2 of the International Continental Scientific Drilling Project Oman Drilling ProjectThere is large petrological and chemical variability in the dunites and harzburgites from Holes CM1A and CM2BPartial melting versus melt‐rock reaction, and the effects of serpentinization and carbonation of dunites and harzburgites are investigated The transition from the oceanic crust to the mantle of Oman has been drilled in the crust‐mantle Holes during Phase 2 of the International Continental Scientific Drilling Project Oman Drilling Project There is large petrological and chemical variability in the dunites and harzburgites from Holes CM1A and CM2B Partial melting versus melt‐rock reaction, and the effects of serpentinization and carbonation of dunites and harzburgites are investigated

The transition from the Semail ophiolite mantle to the underlying metamorphic sole was drilled at ICDP OmanDP Hole BT1B. We analyzed the bulk major, volatile and trace element compositions of the mantle‐derived listvenite series and metamorphic rocks, with the aim to constrain chemical transfers associated with peridotite carbonation along the ophiolite basal thrust. The listvenite series comprise variously carbonated serpentinites and (fuchsite‐bearing) listvenites. They have high CO2(up to 43 wt.%) and variable H2O (0–12 wt.%). Yet, they have compositions close to that of the basal banded peridotites for most major and lithophile trace elements, with fuchsite‐bearing listvenites overlapping in composition with amphibole‐bearing basal lherzolites (e.g., Al2O3= 0.1–2.2 wt.%; Yb = 0.05–1 x CI‐chondrite). The protolith of the listvenite series was likely similar in structure and composition to serpentinized banded peridotites which immediately overlie the metamorphic sole elsewhere in Oman. The listvenite series are enriched in fluid mobile elements (FME) compared to Semail peridotites (up to ∼103–104x Primitive Mantle), with concentrations similar to the underthrusted metabasalts and/or metasediments for Cs, Sr and Ca and sometimes even higher for Pb, Li, As, and Sb (e.g., Li up to 130 μg/g; As up to 170 μg/g). We also observe a decoupling between Sr‐Ca enrichments and other FME, indicating interactions with several batches of deep CO2‐rich fluids transported along the basal thrust. These results suggest that peridotite carbonation could represent one of the major trap‐and‐release mechanisms for carbon, water and FME along convergent margins. Ophiolites are sections of oceanic lithosphere emplaced on‐land as tectonic plates converge. The faults developed at their base are analogues to plate interfaces in subduction zones, where mass transfers occur and play a key role in the global cycling of elements. A core was drilled at the base of the Semail Ophiolite, where variously hydrated and carbonated mantle rocks known as serpentinites and listvenites witnessed major fluid fluxes. Reactions with CO2‐bearing fluids (carbonation reaction) enhanced the mobility of elements during mass transfers along the basal thrust. We measured the elemental composition of 84 samples spaced along this core. Results indicate that CO2‐bearing fluids derive from at least two sources or pathways. As peridotites reacted, their volume increased, causing cracking, helping the ingress of reactive fluids and allowing (almost) complete carbonation of the basal ophiolite mantle. Carbon as well as many elements such as cesium, arsenic, antimony, lead, became enriched in these rocks. If forming in subduction zones, listvenites may act as temporary storage for these elements and impact global chemical cycles. BT1B listvenite series and metamorphic sole derive from partially serpentinized basal banded peridotites and alkaline basalts respectivelyChemical redistribution suggests reactions with several batches of CO2‐rich fluids over various flow paths parallel to the basal thrustListvenitization due to CO2metasomatism could represent a major trap‐and‐release mechanism for CO2, fluid mobile elements and H2O along convergent margins BT1B listvenite series and metamorphic sole derive from partially serpentinized basal banded peridotites and alkaline basalts respectively Chemical redistribution suggests reactions with several batches of CO2‐rich fluids over various flow paths parallel to the basal thrust Listvenitization due to CO2metasomatism could represent a major trap‐and‐release mechanism for CO2, fluid mobile elements and H2O along convergent margins

The composition of the intrusive gabbroic lower oceanic crust remains poorly characterized in comparison to the extrusive portion of the oceanic crust, especially for intermediate‐fast spreading mid‐ocean ridges. This is a consequence of limited exposures of extant lower oceanic crust or ophiolites similar to mid‐ocean ridge crust. One of the best analogues for mid‐ocean ridge crust is the southern Samail ophiolite that formed during a period of rapid seafloor spreading above a nascent subduction zone. Here, we focus on the geochemical stratigraphy (whole rock and mineral major and trace element compositions) of the 5,200 m‐thick, lower crustal, Wadi Khafifah section of the Wadin Tayin massif in the southern Samail (Oman) ophiolite. Gabbros from the lowermost 3,700 m of this section (the “lower gabbros”) show no systematic changes in composition with height above the Mantle Transition Zone. In contrast, gabbros from the uppermost 1,500 m (the “upper gabbros”) display marked increases in incompatible trace element concentration with increasing height. Liquids in equilibrium with the lower gabbros have major and trace element compositions that overlap with those measured in the upper gabbros and sheeted dikes. Upper gabbros preserve mineral cores with primitive major element compositions that overlap with the range of lower gabbros; however, upper gabbro whole rock compositions are significantly more enriched in incompatible trace elements relative to the lower gabbros. Our data reveal that the upper gabbros are a composite of accumulated minerals derived from primitive melts and a large fraction of evolved melts derived from the fractionation of the lower gabbros. We propose a new “Full Sheeted Sills” model for the lower oceanic crust in which primitive magmas from the mantle are emplaced throughout the lower crust and crystallized in situ. After diking events, evolved magmas leave the lower gabbros and replenish the upper gabbros, thereby contributing to the higher incompatible trace element budget in the upper gabbros relative to the lower gabbros. Our reconstructed bulk compositions of the lower plutonic crust and the bulk oceanic crust from the Wadi Khafifah section yield a plausible primary mantle‐derived magma composition in equilibrium with depleted mid‐ocean ridge basalts mantle. The composition and structure of the oceanic crust is traditionally difficult to estimate due to lack of exposure. Using rocks that crystallized from magmas at a submarine spreading center, we present major and trace element geochemical data for the entire lower oceanic crust. Our data shows how the lowermost sections of the oceanic crust are related to the uppermost intrusive and extrusive by crystallization and melt migration before and after eruptions. The bulk composition of our crustal section is in chemical equilibrium with the mantle and therefore represents a plausible primary mantle melt. The intrusive oceanic crust is divided into lower gabbros and upper gabbros on the basis of incompatible trace element concentrations and mineral compositional variabilityThe lower oceanic crust is accreted throughout in small sills of primitive meltThe upper gabbros additionally receive the fractionated melts from the crystallization of the lower gabbros via melt migration The intrusive oceanic crust is divided into lower gabbros and upper gabbros on the basis of incompatible trace element concentrations and mineral compositional variability The lower oceanic crust is accreted throughout in small sills of primitive melt The upper gabbros additionally receive the fractionated melts from the crystallization of the lower gabbros via melt migration

Objectives: To describe the characteristics of lipoprotein lipase (LPL)-deficient patients seen in infancy and to evaluate the safety and efficacy of severe fat restriction. Methods: Children <1 year old presenting with chylomicronemia between 1972 and 1995 were identified, and their clinical courses were reviewed retrospectively. Results: LPL deficiency was demonstrated in 16 infants who presented with irritability (n = 7), lower intestinal bleeding (n = 2), pallor, anemia, or splenomegaly (n = 5), and a family history or fortuitous discovery (n = 2). All plasma samples were lactescent at presentation. Chylomicronemia responded rapidly to dietary fat restriction, and it was possible to maintain satisfactory metabolic control for a prolonged period of time. Only 1 adolescent girl had an episode of pancreatitis associated with the use of oral contraceptives. No persistent adverse effects on growth were seen. We obtained abnormal values for serum iron, alkaline phosphatase, and total calcium. Conclusions: The presentation of LPL deficiency is heterogeneous during infancy. Close dietary monitoring is required to avoid nutritional deficiencies. Estrogen therapy should be avoided in LPL-deficient patients. (J Pediatr 1998;133:417-23)

Context.A 3.4 μm absorption band (around 2900 cm-1), assigned to aliphatic C-H stretching modes of hydrogenated amorphous carbons (a-C:H), is widely observed in the diffuse interstellar medium, but disappears or is modified in dense clouds. This spectral difference between different phases of the interstellar medium reflects the processing of dust in different environments. Cosmic ray bombardment is one of the interstellar processes that make carbonaceous dust evolve.

Context. Hydrogenated amorphous carbons (a-C:H or HAC) have proved to be excellent analogs of interstellar dust observed in galaxies diffuse interstellar medium (DISM) through infrared vibrational absorption bands (3.4 μm, 6.8 μm, and 7.2 μm bands). They exhibit photoluminescence (PL) after excitation by UV-visible photons, and are possible carriers for the extended red emission (ERE), a broad red emission band observed in various interstellar environments.Aims. As many candidate materials/molecules can photoluminesce in the visible, along with the carrier abundance, the PL efficiency represents one of the strongest constraints set by such ERE observations. We wish to precisely characterize the PL behavior of a-C:H as a family of materials.Methods. The a-C:H samples are produced in the form of films deposited on substrates by plasma-enhanced chemical vapor deposition. The produced films were analyzed in transmission by UV-visible and IR spectroscopy, and the wavelength dependent PL spectra were recorded. The intrinsic absolute quantum yield ηwas then rigorously calculated taking self-absorption of the PL by the film and interfaces effects into account.Results. A wide range of different laboratory synthesized a-C:H were analyzed. Their PL properties are dependent on the optical gap $E_\mathrm{04}$: when $E_\mathrm{04}$decreases from 4.3 eV to 2.8 eV, the a-C:H vary from highly ($\eta \sim 1\%$) yellow photoluminescent soft materials to hard materials that emit a wider PL band in the red spectral range, with a lower efficiency (η~ 0.01–0.1%). For any given a-C:H, the PL characteristics (central wavelength, band width and efficiency) are found to be essentially constant over the explored excitation range ($\lambda_{\rm exc}$$\ga$250 nm). We compared the characteristics of the produced interstellar dust analog to the constraints imposed by the ERE observations.Conclusions. As for ERE observations, PL efficiencies and band widths of a-C:H are both correlated to the PL central wavelengths. The excitation responsible for the a-C:H emission is efficient over a wide spectral range that matches the ERE excitation. The present a-C:H encounter difficulties for the diffuse ISM ERE observations ($\eta \ge 10$%) in simultaneously satisfying the high quantum yield criteria and PL spectral characteristics. We still need to investigate the role of a small number of residual oxygen atoms in the laboratory-produced a-C:H network in quenching the PL yield, as well as to consider the interstellar temperature effect for our analogs.