Linking Sediment Transport and Stratigraphy on the Continental Shelf

The goal of the shelf sediment dynamics component of STRATAFORM is to link sediment transport processes active on the continental shelf to the formation and preservation of event beds in shelf sediment deposits. An approach combining shelf sediment-transport models with high-resolution measurements of water-column and bed properties over periods from several months to several years allows us to make quantitative estimates of bed modification caused by sediment resuspension during episodic transport events. These modifications include erosion and deposition of bed material, formation of graded storm beds, and changes in small-scale bed surface morphology. The characteristics of the resulting “event bed” (thickness, grading, physical structures) are a function of flow and bed properties, depending on both temporal and spatial variations in sediment transport

Intestinal transplantation in composite visceral grafts or alone

Under FK 506-based immunosuppression, the entire cadaver small bowel except for a few proximal and distal centimeters was translated to 17 randomly matched patients, of whom two had antigraft cytotoxic antibodies (positive cross-match). Eight patients received the intestine only, eight had intestine in continuity with the liver, and one received a full multivisceral graft that included the liver, stomach, and pancreas. One liver-intestine recipient died after an intestinal anastomotic leak, sepsis, and graft- versus-host disease. The other 16 patients are alive after 1 to 23 months, in one case after chronic rejection, graft removal, and retransplantation. Twelve of the patients have been liberated from total parenteral nutrition, including all whose transplantation was 2 months or longer ago. The grafts have supported good nutrition, and in children, have allowed growth and weight gain. Management of these patients has been difficult and often complicated, but the end result has been satisfactory in most cases, justifying further clinical trials. The convalescence of the eight patients receiving intestine only has been faster and more trouble free than after liver-intestine or multivisceral transplantation, with no greater difficulty in the control of rejection

Intestinal transplantation in composite visceral grafts or alone

Under FK 506-based immunosuppression, the entire cadaver small bowel except for a few proximal and distal centimeters was translated to 17 randomly matched patients, of whom two had antigraft cytotoxic antibodies (positive cross-match). Eight patients received the intestine only, eight had intestine in continuity with the liver, and one received a full multivisceral graft that included the liver, stomach, and pancreas. One liver-intestine recipient died after an intestinal anastomotic leak, sepsis, and graft- versus-host disease. The other 16 patients are alive after 1 to 23 months, in one case after chronic rejection, graft removal, and retransplantation. Twelve of the patients have been liberated from total parenteral nutrition, including all whose transplantation was 2 months or longer ago. The grafts have supported good nutrition, and in children, have allowed growth and weight gain. Management of these patients has been difficult and often complicated, but the end result has been satisfactory in most cases, justifying further clinical trials. The convalescence of the eight patients receiving intestine only has been faster and more trouble free than after liver-intestine or multivisceral transplantation, with no greater difficulty in the control of rejection

Ear care: an update for nurses (part 1)

A healthy ear is vital not just for hearing, but for balance and for full engagement with the community. In the first of two articles, Kat Millward reviews the anatomy of the ear, outlines methods of dealing with cerumen, and discusses methods of assessment and diagnosis Our ears are essential for both hearing and balance. Up to 4% of the population will have difficulties with their ears relating to impacted cerumen and many of them will present in primary care with ear discomfort or hearing difficulties. In the first of two articles, we review the anatomy and physiology of the ear and cerumen production, followed by a discussion of the key aspects of making an assessment using the SOAP (Subjective, Objective, Assessment, Plan) mnemonic

Recurrent De Novo NAHR Reciprocal Duplications in the ATAD3 Gene Cluster Cause a Neurogenetic Trait with Perturbed Cholesterol and Mitochondrial Metabolism.

Recent studies have identified both recessive and dominant forms of mitochondrial disease that result from ATAD3A variants. The recessive form includes subjects with biallelic deletions mediated by non-allelic homologous recombination. We report five unrelated neonates with a lethal metabolic disorder characterized by cardiomyopathy, corneal opacities, encephalopathy, hypotonia, and seizures in whom a monoallelic reciprocal duplication at the ATAD3 locus was identified. Analysis of the breakpoint junction fragment indicated that these 67 kb heterozygous duplications were likely mediated by non-allelic homologous recombination at regions of high sequence identity in ATAD3A exon 11 and ATAD3C exon 7. At the recombinant junction, the duplication allele produces a fusion gene derived from ATAD3A and ATAD3C, the protein product of which lacks key functional residues. Analysis of fibroblasts derived from two affected individuals shows that the fusion gene product is expressed and stable. These cells display perturbed cholesterol and mitochondrial DNA organization similar to that observed for individuals with severe ATAD3A deficiency. We hypothesize that the fusion protein acts through a dominant-negative mechanism to cause this fatal mitochondrial disorder. Our data delineate a molecular diagnosis for this disorder, extend the clinical spectrum associated with structural variation at the ATAD3 locus, and identify a third mutational mechanism for ATAD3 gene cluster variants. These results further affirm structural variant mutagenesis mechanisms in sporadic disease traits, emphasize the importance of copy number analysis in molecular genomic diagnosis, and highlight some of the challenges of detecting and interpreting clinically relevant rare gene rearrangements from next-generation sequencing data

The effect of distance on reaction time in aiming movements

Target distance affects movement duration in aiming tasks but its effect on reaction time (RT) is poorly documented. RT is a function of both preparation and initiation. Experiment 1 pre-cued movement (allowing advanced preparation) and found no influence of distance on RT. Thus, target distance does not affect initiation time. Experiment 2 removed pre-cue information and found that preparing a movement of increased distance lengthens RT. Experiment 3 explored movements to targets of cued size at non-cued distances and found size altered peak speed and movement duration but RT was influenced by distance alone. Thus, amplitude influences preparation time (for reasons other than altered duration) but not initiation time. We hypothesise that the RT distance effect might be due to the increased number of possible trajectories associated with further targets: a hypothesis that can be tested in future experiments

Solar-type dynamo behaviour in fully convective stars without a tachocline

In solar-type stars (with radiative cores and convective envelopes), the magnetic field powers star spots, flares and other solar phenomena, as well as chromospheric and coronal emission at ultraviolet to X-ray wavelengths. The dynamo responsible for generating the field depends on the shearing of internal magnetic fields by differential rotation. The shearing has long been thought to take place in a boundary layer known as the tachocline between the radiative core and the convective envelope. Fully convective stars do not have a tachocline and their dynamo mechanism is expected to be very different, although its exact form and physical dependencies are not known. Here we report observations of four fully convective stars whose X-ray emission correlates with their rotation periods in the same way as in Sun-like stars. As the X-ray activity - rotation relationship is a well-established proxy for the behaviour of the magnetic dynamo, these results imply that fully convective stars also operate a solar-type dynamo. The lack of a tachocline in fully convective stars therefore suggests that this is not a critical ingredient in the solar dynamo and supports models in which the dynamo originates throughout the convection zone.Comment: 6 pages, 1 figure. Accepted for publication in Nature (28 July 2016). Author's version, including Method

Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons

Fundamental interactions induced by lattice vibrations on ultrafast time scales become increasingly important for modern nanoscience and technology. Experimental access to the physical properties of acoustic phonons in the THz frequency range and over the entire Brillouin zone is crucial for understanding electric and thermal transport in solids and their compounds. Here, we report on the generation and nonlinear propagation of giant (1 percent) acoustic strain pulses in hybrid gold/cobalt bilayer structures probed with ultrafast surface plasmon interferometry. This new technique allows for unambiguous characterization of arbitrary ultrafast acoustic transients. The giant acoustic pulses experience substantial nonlinear reshaping already after a propagation distance of 100 nm in a crystalline gold layer. Excellent agreement with the Korteveg-de Vries model points to future quantitative nonlinear femtosecond THz-ultrasonics at the nano-scale in metals at room temperature