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Inoceramus is an epibenthic bivalve which lived in a wide variety of paleoenvironments encompassing a broad range of paleodepths. A survey of all Cretaceous sediments from Deep Sea Drilling Project legs 1-69 and 75 revealed over 500 Inoceramus specimens at twenty sites. Of these, 47 well-preserved Late Cretaceous specimens from the South Atlantic, Pacific and Indian Oceans were analyzed for oxygen and carbon isotopes. The specimens exhibit small internal isotopic variability and oxygen isotopic paleotemperatures that are consistent with a deep-sea habitat. Paleotemperatures ranging from 5 to 16°C show that Late Cretaceous oceans were significantly warmer than the present oceans. The data suggest that deep water was formed both by cooling at high latitudes and by evaporation in the subtropics. © 1982.

Liquid metal (LM) composites, which consist of LM droplets dispersed in highly deformable elastomers, have recently gained interest as a multifunctional material for soft robotics and electronics. The incorporation of LM into elastic solids allows for unique combinations of material properties such as high stretchability with thermal and electrical conductivity comparable to metals. However, it is currently a challenge to incorporate LM composites into integrated systems consisting of diverse materials and components due to a lack of adhesion control. Here, a chemical anchoring methodology to increase adhesion of LM composites to diverse substrates is presented. The fracture energy increases up to 100× relative to untreated surfaces, with values reaching up to 7800 J m -2 . Furthermore, the fracture energy, tensile modulus, and thermal conductivity can be tuned together by controlling the microstructure of LM composites. Finally, the bonding technique is used to integrate LM composites with functional electronic components without encapsulation or clamping, allowing for extreme deformations while maintaining exceptional thermal and electrical conductivity. These findings can accelerate the adoption of LM composites into complex soft robotic and electronic systems where strong, reliable bonding between diverse materials and components is required., (© 2022 The Authors. Small published by Wiley-VCH GmbH.)

Single crystal studies provide a better understanding of the basic properties of organic photovoltaic devices. Therefore, in this work, rubrene single crystals with a thickness of 250 nm to 1000 nm were used to produce an inverted bilayer organic solar cell. Subsequently, polycrystalline rubrene (orthorhombic, triclinic) and amorphous bilayer solar cells of the same thickness as single crystals were studied to make comparisons across platforms. To investigate how single crystal, polycrystalline (triclinic-orthorhombic) and amorphous forms alter the charge carrier recombination mechanism at the rubrene/PCBM interface, light intensity measurements were carried out. The light intensity dependency of the J SC , V OC and FF parameters in organic solar cells with different forms of rubrene was determined. Monomolecular (Shockley Read Hall) recombination is observed in devices employing amorphous and polycrystalline rubrene in addition to bimolecular recombination, whereas the single crystal device is weakly affected by trap assisted SRH recombination due to reduced trap states at the donor acceptor interface. To date, the proposed work is the only systematic study examining transport and interface recombination mechanisms in organic solar cells produced by different structure forms of rubrene.

Biological organisms such as the octopus can reconfigure their shape and properties to perform diverse tasks. However, soft machines struggle to achieve complex configurations, morph into shape to support loads, and go between multiple states reversibly. Here, we introduce a multifunctional shape-morphing material with reversible and rapid polymorphic reconfigurability. We couple elastomeric kirigami with an unconventional reversible plasticity mechanism in metal alloys to rapidly ( < 0.1 seconds) morph flat sheets into complex, load-bearing shapes, with reversibility and self-healing through phase change. This kirigami composite overcomes trade-offs in deformability and load-bearing capacity and eliminates power requirements to sustain reconfigured shapes. We demonstrate this material through integration with onboard control, motors, and power to create a soft robotic morphing drone, which autonomously transforms from a ground to air vehicle and an underwater morphing machine, which can be reversibly deployed to collect cargo.

Wearable electronics allow for new and immersive experiences between technology and the human body, but conventional devices are made from rigid functional components that lack the necessary compliance to safely interact with human tissue. Recently, liquid inclusions have been incorporated into elastomer composites to produce functional materials with high extensibility and ultrasoft mechanical responses. While these materials have shown high thermal and electrical conductivity, there has been an absence of research into compliant magnetic materials through the incorporation of magnetic fluids. Compliant magnetic materials are important for applications in soft matter engineering including sensing, actuation, and power transfer for soft electronics and robotics. In this work, we establish a new class of highly functional soft materials with advanced magnetic and mechanical properties by dispersing magnetic colloidal suspensions as compliant fluid inclusions into soft elastomers. Significantly, the rigid magnetic particles are encapsulated by the fluid. This mechanically cloaks the solid particles and enables a fluid-like mechanical response while imparting high magnetic permeability to the composite. This microstructure reduces the modulus of the composite below that of the initial elastomer to <40 kPa while increasing the permeability by over 100% to greater than 2. We demonstrate the functionality of these materials through conformable magnetic backplanes, which enables a completely soft, coupled inductor system capable of transferring power up to 100% strain and wearable devices for wireless power transfer.

In 1996 we published a study evaluating the difference between patient and surgeon opinion on the aesthetic outcome of reduction mammaplasty (see Ref. 1). The patients rated the aesthetic outcome of their surgery as significantly higher than the consultant panel. The surgical panel suggested scope for improvement. Areas of dissatisfaction were poor scarring, high placement of the nipple areola complex and high rates of revision surgery. Fifteen years on, the same team has regrouped to repeat this assessment. In 1996 the consultants scored their own patient results. In 2011 they graded the results of their former trainee who has modified her operative technique to address aesthetic problems highlighted in the first study. Forty-four patients attended a review clinic at least one year post reduction mammaplasty. Patient scored their satisfaction using the original questionnaire employed in 1996. The cohort were photographed and their images graded blindly by the original surgical panel. Statistical analysis was performed by the original statistician. The patients graded aesthetic aspects of body harmony, breast mound appearance, nipple areolar complex appearance and post-operative scarring significantly more positively (p<0.01) than both the 1996 patient cohort and surgical panel. The consultant panel showed a trend for more positive grades for all aesthetic features assessed versus their previous views but this was only significant for breast mound symmetry. They expressed that there was a decrease in post-operative breast ptosis (p<0.04) and improvement in the nipple areolar complex position (p=0.02). The rate of revision surgery has decreased from 53% to 16% between the studies. In keeping with clinical audit, outcomes have been assessed and modifications implemented to address aesthetic concerns. Assessment of outcomes following the modifications demonstrates a trend for increased patient and surgeon satisfaction. Patient satisfaction however still exceeds that of the surgeons., (Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)

The column method of Christner and Fetter (Steroids 24: 327, 1974) has been modified to give a simple, rapid assay for unconjugated estriol in serum. Estriol is isolated from serum by being retained on a Sephadex column, while estriol conjugates and serum proteins are eluted. The sample and labeled estriol compete for antibody on the column. Antibody is eluted, removing proportional amounts of sample and labeled estriol. Our modifications include using stable serum-based standards, shortening the incubation to 10 min, complete removal of conjugates, and regeneration of the columns so that they can be used repeatedly. The assay, which can be completed in 2 h, has a mid-range interassay CV of 8.2%.

Three-dimensional numerical ocean circulation model experiments that were designed to evaluate the circulation characteristics for the mid-Cretaceous ( approximately 100 million years ago) show that the primary direction of flow through the Tethys Ocean was eastward; in contrast, a westward flowing circumglobal Tethys current has been a consistent feature of earlier reconstructions of Cretaceous ocean circulation. The model studies demonstrate that (i) ocean circulation is sufficiently sensitive to the role of continental positions, sea level, and climate to limit the application of modern analogs to past circulations, and (ii) reconstructions based on limited biogeographic data may not provide unique surface circulation patterns.

A precise and sensitive method is described for the determination of the antidepressant drug tranylcypromine in human plasma and urine using high-resolution gas chromatography. The drug, together with an added internal standard, is extracted from the plasma or urine sample, derivatized with heptafluorobutyric anhydride and analysed on an OV-225 support-coated open-tubular glass capillary column with nitrogen-sensitive detection. The method has been applied to the measurement of tranylcypromine levels in plasma and urine from both healthy volunteers and from psychiatric patients receiving a therapeutic dosage of the drug.

We have quantitatively investigated the mechanisms that could explain the warm, equable climate that is believed to have been typical of the mid-Cretaceous (100 million years ago). By performing simulations with a climate model based on zonal energy balance, we demonstrate that past changes in geography were important in bringing about climatic change. However, the meridional distribution of Cretaceous temperatures cannot be successfully simulated unless additional physical "feedback mechanisms" are included in the model. These mechanisms may involve cloud and meridional heat transport changes. We also conclude that paleoclimatologists should reexamine carefully both existing data and their interpretations with regard to reconstruction of Cretaceous tropical and polar surface temperatures.

In a patient receiving penicillamine for treatment of rheumatoid arthritis, antibodies to insulin developed, which resulted in symptomatic hypoglycemia. When 30 additional patients receiving penicillamine were screened, another patient was discovered to have antibodies to insulin. The level of antibody fell sharply in both patients after penicillamine was discontinued. This particular immunologic reaction to penicillamine has not been reported previously.

A competitive binding assay for serum thyroxine has been automated, with the use of small, reusable Sephadex columns to separate thyroxine from endogenous thyroid-binding globulin and later to separate the bound and free thyroxine. Sixty samples an hour are run through columns, which are held in an aluminum turntable rotated by a fraction collector motor. Reagents and samples are fed to the columns by a proportioning pump. Waste eluates are collected and drained to the sink by a Teflon tray positioned between the columns and counting tubes, also held by the turntable. A cut out area in the tray allows one to collect the bound fraction, which can then be counted in a scintillation counter. Values are calculated and printed by a desk calculator interfaced with the scintillation counter. The "day-to-day" CV for this method is 5%. The accuracy is satisfactory when tested by comparison with other methods, by recoveries, and by linearity of dilutions.

Sucrose density-gradient analysis is one method of identifying specific estrogen and progesterone receptors in mammary tumor tissue. Use of the vertical rotor makes this practical for routine applications in the clinical laboratory by increasing the number of samples that can be run at one time and shortening the centrifuge time from 18 to less than 2 h. The separations and reproducibility compare favorably with those obtained with a swinging-bucket rotor.