Search

A baited camera has recorded a lysianassid amphipod that is twice as large as the largest amphipod previously recorded. The locality for this mobile omnivore is the sterile bottom of the eastern North Pacific Ocean, at a depth of 5304 meters.

The theoretical possibility of self-supporting cables extending into space from earth and from extraterrestrial rotating or revolving bodies is examined. In principle, augmentation (and duplication) of the installation and the launching of masses into orbit or into space could be accomplished with energy derived entirely from the rotation of the central body. In practice, a portion of the total energy requirement would probably be supplied by simple mechanical devices.

A series of experiments was performed to test the possibility of using OPEN-end pipes with float-type recorders for measuring wave heights, for the purpose of applying these data to the planning of coastal engineering structures. The main problem was one of resonance in the tubes. This was particularly pronounced in actual installation for wave periods of from one to six seconds. A mathematical analysis has been made for the case of a train of waves of constant period. It was shown that the hand of frequencies encountered in the ocean would make it quite difficult if not a practical impossibility to analyze data obtained by this method.

The University of California in cooperation with the Bureau of Ships, United States Navy, has been engaged in field investigations of beach and surf conditions at many of the more important beaches of the West Coast of the United States. One of the first problems encountered in these studies was that of establishing a datum on each beach which would be related to the tidal datum (Meat lower low water) without running long lines of levels from points of known elevation. In an effort to discover a simple way of determining this datum, investigations were initiated, by means of which it was hoped to be able to connect, empirically, the elevation of the ground water in the teach with the predicted tide. Although the original purpose did not prove practicable, considerable interesting data have been obtained. It is the purpose of this paper to present some of these data for the benefit of other investigators.

The thermopile or Mark V wave meter is designed to be a low cost, simple yet durable instrument which can be considered expendable upon Its installation in the ocean. Its electrical characteristics are such that the cable requirements are not rigorous. Its construction is simple. A synthetic rubber bellows is mounted on a plastic base which is in turn mounted on a brass cable connection. A thermopile is mounted inside the bellows with one group of junctions in contact with the air chamber of the bellows, and the reference junctions, insulated from the air chamber, in thermal contact with the surrounding sea water. Thus when a wave passes over the unit, the crest and trough produce a compression and expansion of the bellows with the corresponding temperature change in the gas due to the polytropic cycle. The temperature difference between the air chamber and the sea water causes an emf from the thermopile, which is transmitted to shore by means of a two-conductor submarine cable, and recorded on a commercial null recorder.

Johnson introduces the subject of refraction of surface waves by currents. This writer has observed these phenomena qualitatively on many occasions and under varying circumstances. The effect of ebb and flood currents in entrance channels to estuaries is marked. During the winter at many harbors on the northern Pacific Coast the entrance channels rarely are passable during the ebb. The bar requently may be negotiated only at the last of the flood, this being the optimum condition of depth and wave refraction by currents. In this connection the following are typical extracts from sailing directions [U.S. Coast And Geodetic Survey, 1942]

In the construction of refraction diagrams for ocean waves the rays (orthogonals) can be drawn more accurately if the approximate formula Δα = (ΔL/Lave) tan α, used by Johnson, O'Brien, and Isaacs [1948] in the preparation of refraction protractors, is replaced by Δα = sin-1 [(1 + ΔL/L) sin α] − α. In these formulas, α is the angle between wave crest and depth contour and L the wave length taken at the beginning of any contour interval; Δα and ΔL are the corresponding changes over the contour interval. A modified procedure for the construction of rays is presented.

A process is described which may be of importance in beach and nearshore development and which may account for surging in the surf zone as well as other phenomena. It is shown how a group front may be refracted according to one law as it approaches a coast and then, after reflection, proceed seaward under quite a different law. This permits the outgoing wave to move in a direction that it could not ordinarily attain, and causes “trapping” under many conditions. Stoneley's theory of refraction of energy fronts is further developed to permit quantitative investigation of group refraction on various types of shores. On the basis of the assumed hypothesis, the outgoing surf beat may be totally reflected from deep water, then reflected from the beach, a process which can occur repeatedly and result in newly arriving groups with variable phase relationships. Theory and techniques are developed for the investigation of the surf-beat path. The refraction of the reflected groups is shown to display regions of high convergence, divergence, and reinforcement.

A mechanism is described by which surface gravity waves generated in shallow water may be totally reflected from deep water. The mechanism by which waves generated in deep water may be “captured” is also discussed.

Introduction Our objective was to determine the interrelationships of interleukin (IL)-6 receptor inhibition with haemoglobin, acute-phase reactants and iron metabolism markers (including hepcidin) in patients with rheumatoid arthritis (RA). Methods Data of patients receiving tocilizumab or placebo in the MEASURE study were analysed. We investigated associations at baseline and during tocilizumab treatment among haemoglobin, parameters of haemoglobin and iron homeostasis [ferritin, total iron-binding capacity (TIBC), hepcidin, haptoglobin], IL-6 and acute-phase reactants [C-reactive protein (CRP), erythrocyte sedimentation rate (ESR)] to identify statistical correlates of rise in haemoglobin level. Results At baseline, CRP and haptoglobin were inversely correlated (modestly) with haemoglobin levels. After treatment with tocilizumab, CRP, hepcidin, ferritin and haptoglobin levels fell alongside increases in TIBC and haemoglobin. The falls in CRP, hepcidin and haptoglobin levels in the first 2 weeks correlated with a week 12 rise in TIBC and haemoglobin. Conclusions Inflammatory anaemia improves in patients with RA treated with tocilizumab. This improvement correlates with the degree of suppression of systemic inflammation, reduction in hepcidin and haptoglobin and increase in iron-binding capacity. These clinical data provide evidence of a role for IL-6 signalling in the inflammatory anaemia of RA.

Introduction Analyses of large clinical datasets from early arthritis cohorts permit the development of algorithms that may be used for outcome prediction in individual patients. The value added by routine use of musculoskeletal ultrasound (MSUS) in an early arthritis setting, as a component of such predictive algorithms, remains to be determined. Methods The authors undertook a retrospective analysis of a large, true-to-life, observational inception cohort of early arthritis patients in Newcastle upon Tyne, UK, which included patients with inflammatory arthralgia but no clinically swollen joints. A pragmatic, 10-minute MSUS assessment protocol was developed, and applied to each of these patients at baseline. Logistic regression was used to develop two "risk metrics" that predicted the development of a persistent inflammatory arthritis (PIA), with or without the inclusion of MSUS parameters. Results A total of 379 enrolled patients were assigned definitive diagnoses after ≥12 months follow-up (median 28 months), of whom 162 (42%) developed a persistent inflammatory arthritis. A risk metric derived from 12 baseline clinical and serological parameters alone had an excellent discriminatory utility with respect to an outcome of PIA (area under receiver operator characteristic (ROC) curve 0.91; 95% CI 0.88 to 0.94). The discriminatory utility of a similar metric, which incorporated MSUS parameters, was not significantly superior (area under ROC curve 0.91; 95% CI 0.89 to 0.94). Neither did this approach identify an added value of MSUS over the use of routine clinical parameters in an algorithm for discriminating PIA patients whose outcome diagnosis was rheumatoid arthritis (RA). Conclusions MSUS use as a routine component of assessment in an early arthritis clinic did not add substantial discriminatory value to a risk metric for predicting PIA.