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Earlier large-scale Greenland ice sheet sea-level projections (e.g., those run during the ice2sea and SeaRISE initiatives) have shown that ice sheet initial conditions have a large effect on the projections and give rise to important uncertainties. The goal of the initMIP-Greenland intercomparison exercise is to compare, evaluate and improve the initialisation techniques used in the ice sheet modelling community and to estimate the associated uncertainties in modelled mass changes. initMIP-Greenland is the first in a series of ice sheet model intercomparison activities within ISMIP6 (the Ice Sheet Model Intercomparison Project for CMIP6), which is the primary activity within the Coupled Model Intercomparison Project - phase 6 (CMIP6) focusing on the ice sheets. Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of 1) the initial present-day state of the ice sheet and 2) the response in two idealised forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without additional forcing) and in response to a large perturbation (prescribed surface mass balance anomaly), and should not be interpreted as sea-level projections. We present and discuss results that highlight the diversity of data sets, boundary conditions and initialisation techniques used in the community to generate initial states of the Greenland ice sheet. We find good agreement across the ensemble for the dynamic response to surface mass balance changes in areas where the simulated ice sheets overlap, but differences arising from the initial size of the ice sheet. The model drift in the control experiment is reduced for models that participated in earlier intercomparison exercises.

This publication concerns the synthesis of a novel class of hybrid thermoset/thermoplastic elastomers, i.e., double cross‐linked polyisobutylene‐based polyurethanes (xPIB‐PUs), together with their processing and some key properties. These materials are designed to exhibit a combination of properties for indwelling medical applications, specifically for heart valve prostheses. The chemical cross‐links are introduced by well‐defined 3‐arm PIB stars fitted with HO‐end groups of molecular weights (MWs) of Mn = 3081 and 9000 g mole−1 and narrow MW dispersities (<1.3). Processibility of xPIB‐PU containing 70 wt% PIB (for biocompatibility and calcification resistance) is achieved by driving the syntheses to high conversions (>97%) close to but still below the gel point and completing the cross‐linking in heated molds. The processibility period (minutes) is controlled by controlling the MW of the cross‐linking agent in the 3081 to 9000 g mole−1 range. Blends of 3‐arm stars and linear bifunctional PIBs can also control the processibility period. The creep resistance of xPIB‐PU is significantly improved (from 13.2% to 5.5%) relative to physically cross‐linked PIB‐PU. xPIB‐PUs exhibit negligible permanent set (1–2%), and high Young's modulus (41 MPa). The stress/strain properties of xPIB‐PUs are also investigated. The data clearly show the contribution of two modes of cross‐linking. [ABSTRACT FROM AUTHOR]

Students at a college or university who receive need-based financial aid, receive a tremendous financial resource compared to those students who do not receive need based financial aid. A sample of 100 students from various backgrounds and skills were surveyed. The survey asked questions of the two student groups: received need based financial aid group and non-need based financial aid group. The overall questions were intended to identify specific traits and measures of the student's performance.

Introduction: Traumatic brain injury (TBI) is a major cause of death and disability and in recent years has been increasingly reported even in developing countries. Computed Tomography (CT) plays a key role in accurate TBI diagnosis and management. The objective of this study was to document the pattern of CT findings in TBI cases reported from Igbo people, in Nigeria. Method: In this retrospective, cross-sectional study, a sample of 287 patients, who were consecutively referred to the CT Unit of the Radiology Department of Federal Medical Centre in Umuahia, Nigeria, between January 2015 and December 2016, on account of trauma to the head was reviewed. Only CT scan without contrast and intracranial findings were considered. Descriptive statistics (frequency and percentages) and confidential intervals were collected. Results: After applying exclusion criteria, our sample comprised 242 patients (M = 163, 67.4%; mean age 32.6 ± 17.6 years). The peak age range was 20–29 years. Abnormal findings were reported for 205 patients (84.72%, 95% Confidential Interval [CI] 80.0 to 86.8). Cerebral oedema was the most common finding observed in the study (n = 64, 24.44%, CI 19.03% to 29.85%), followed by subarachnoid haemorrhage (n = 41, 16.94%, CI 12.21% to 21.67%) and epidural haematoma (n = 26, 10.74%, CI 6.84% to 14.64%). Only 37 patients (15.28%) showed normal findings. Main reported causal factors of TBI were: Road Traffic Accidents (RTA) (35.5%), falls (20.2%) and assault (15.7%). Most cases of RTA (34.9%) occurred in the age group of 20–29 years. Discussion and Conclusion: CT brain without contrast is useful in screening of patients with TBI. In this Nigeria-based study the most common cause of TBI was RTA and cerebral oedema was the most common intracranial finding reported.

This series of publications describes research rendering soft polyisobutylene (PIB)‐based thermoplastic elastomers 3D printable by blending with rigid chemically compatible thermoplastics. The molecular structure, morphology, physical properties, and 3D printability of such blends have been systematically investigated. The authors' first report was concerned with the rendering of soft poly(styrene‐b‐isobutylene‐b‐styrene) (SIBS) 3D printable by blending with rigid polystyrene (PS). Here they report the macromolecular engineering of SIBS/polyphenylene oxide (PPO) blends for 3D printing. PPO, a rigid high‐performance thermoplastic, is compatible with the hard PS block in SIBS; however, neither PPO nor SIBS can be directly 3D printed. The microphase‐separated structures and physical properties of SIBS/PPO blends are systematically tuned by controlling blending ratios and molecular weights. Suitable composition ranges and desirable properties of SIBS/PPO blends for 3D printing are optimized. The morphology and properties of SIBS/PPO blends are characterized by an ensemble of techniques, including atomic force microscopy, small‐angle X‐ray scattering, and thermal and mechanical properties testing. The elucidation of processing‐structure‐property relationship of SIBS/PPO blends is essential for 3D printing and advanced manufacturing of high‐performance polymer systems. [ABSTRACT FROM AUTHOR]

Complex copolymers are heated to slowly increasing temperatures on a direct probe (DP) inside the plasma of the atmospheric pressure chemical ionization (APCI) source of a quadrupole ion trap. Slow heating allows for temporal separation of the thermal degradation products according to the stabilities of the bonds being cleaved. The products released from the DP are identified in situ by APCI mass spectrometry and tandem mass spectrometry. DP-APCI experiments on amphiphilic copolymers provide conclusive information about the nature of the hydrophobic and hydrophilic components present and can readily distinguish between copolymers with different comonomer compositions as well as between cross-linked copolymers and copolymer blends with similar physical properties. The dependence of DP-APCI mass spectra on temperature additionally reveals information about the thermal stability of the different domains within a copolymer.