A novel weighting method for satellite magnetic data and a new global magnetic field model

A new data weighting scheme is introduced for satellite geomagnetic survey data. Data weights for individual satellite samples at 20-s spacing are derived from two ‘noise’ (or unmodelled signal) estimators for the sample. First, the standard deviation along the 20 s of satellite track, centred on each sample, is computed as a measure of local magnetic activity. Second a larger-scale noise estimator is defined in terms of a ‘local area vector activity’ (LAVA) index for the sample. This is derived from activity measured at the geographically nearest magnetic observatories to the sample point. Weighting of the satellite data by the inverse-sum-of-squares of these noise estimators then leads to a robust model of the field, the ‘Model of Earth’s Magnetic Environment 2008’, or MEME08, to about spherical harmonic degree 60. Our approach allows vector samples of the field to be used at all magnetic latitudes and, for example, results in a lithospheric magnetic field model with low spectral noise, comparable with other recent global models. We also do not require a particularly complex model parametrization, regularization, or prior data correction to remove estimates of unmodelled source fields

The vertical distribution and biological transport of marine microplastics across the epipelagic and mesopelagic water column.

Plastic waste has been documented in nearly all types of marine environments and has been found in species spanning all levels of marine food webs. Within these marine environments, deep pelagic waters encompass the largest ecosystems on Earth. We lack a comprehensive understanding of the concentrations, cycling, and fate of plastic waste in sub-surface waters, constraining our ability to implement effective, large-scale policy and conservation strategies. We used remotely operated vehicles and engineered purpose-built samplers to collect and examine the distribution of microplastics in the Monterey Bay pelagic ecosystem at water column depths ranging from 5 to 1000 m. Laser Raman spectroscopy was used to identify microplastic particles collected from throughout the deep pelagic water column, with the highest concentrations present at depths between 200 and 600 m. Examination of two abundant particle feeders in this ecosystem, pelagic red crabs (Pleuroncodes planipes) and giant larvaceans (Bathochordaeus stygius), showed that microplastic particles readily flow from the environment into coupled water column and seafloor food webs. Our findings suggest that one of the largest and currently underappreciated reservoirs of marine microplastics may be contained within the water column and animal communities of the deep sea

APC-targeted proinsulin expression inactivates insulin-specific memory CD8+ T cells in NOD mice

Type 1 diabetes (T1D) results from T-cell-mediated autoimmune destruction of pancreatic β cells. Effector T-cell responses emerge early in disease development and expand as disease progresses. Following β-cell destruction, a long-lived T-cell memory is generated that represents a barrier to islet transplantation and other cellular insulin-replacement therapies. Development of effective immunotherapies that control or ablate β-cell destructive effector and memory T-cell responses has the potential to prevent disease progression and recurrence. Targeting antigen expression to antigen-presenting cells inactivates cognate CD8+ effector and memory T-cell responses and has therapeutic potential. Here we investigated this in the context of insulin-specific responses in the non-obese diabetic mouse where genetic immune tolerance defects could impact on therapeutic tolerance induction. Insulin-specific CD8+ memory T cells transferred to mice expressing proinsulin in antigen-presenting cells proliferated in response to transgenically expressed proinsulin and the majority were rapidly deleted. A small proportion of transferred insulin-specific Tmem remained undeleted and these were antigen-unresponsive, exhibited reduced T cell receptor (TCR) expression and H-2Kd/insB15-23 tetramer binding and expressed co-inhibitory molecules. Expression of proinsulin in antigen-presenting cells also abolished the diabetogenic capacity of CD8+ effector T cells. Therefore, destructive insulin-specific CD8+ T cells are effectively inactivated by enforced proinsulin expression despite tolerance defects that exist in diabetes-prone NOD mice. These findings have important implications in developing immunotherapeutic approaches to T1D and other T-cell-mediated autoimmune diseases

Immediate effect of a spinal mobilisation intervention on muscle stiffness, tone and elasticity in subjects with lower back pain - A randomized cross-over trial

Background Despite the lack of objective evidence, spinal manual therapies have been common practice for many years, particularly for treatment of lower back pain (LBP). This exploratory study measured and analysed the effect of a spinal mobilisation intervention on muscle tissue quality in LBP sufferers. Methods 40 people with LBP participated in a within-subject repeated measures cross-over study with intervention and control conditions. A myometer was used to assess the change in para-spinal muscle tissue quality before and after the intervention. Analysis considered the magnitude of muscle response together with individual covariates as potential contributors. Results A significant post-intervention reduction was observed in muscle stiffness (p = 0.012, η 2 partial = 0.15), tone (p = 0.001, η 2 partial = 0.25) and elasticity (p = 0.001, η 2 partial = 0.24). Significant increases were seen in 2 variables post-control: stiffness (p = 0.004, η 2 partial = 0.19), tone (p = 0.006, η 2 partial = 0.18) and a significant decrease in elasticity (p ˂ 0.000, η 2 partial = 0.3). Significant contributing covariates include baseline stiffness, BMI, waist circumference and sex. Baseline stiffness and tone were significantly correlated to their response levels. Conclusions The significant reduction in all muscle tissue qualities following the intervention provide preliminary data for an evidence-based LBP therapeutic. Baseline stiffness, BMI, waist circumference and sex could act as significant contributors to magnitude of response. The results warrant further investigation into spinal mobilisation therapies to further build the objective evidence base

Climate Variability in West Antarctica Derived from Annual Accumulation-Rate Records from ITASE Firn/Ice Cores

Thirteen annually resolved accumulation-rate records covering the last similar to 200 years from the Pine Island-Thwaites and Ross drainage systems and the South Pole are used to examine climate variability over West Antarctica. Accumulation is controlled spatially by the topography of the ice sheet, and temporally by changes in moisture transport and cyclonic activity. A comparison of mean accumulation since 1970 at each site to the long-term mean indicates an increase in accumulation for sites located in the western sector of the Pine Island-Thwaites drainage system. Accumulation is negatively associated with the Southern Oscillation Index (Sol) for sites near the ice divide, and periods of sustained negative Sol (1940-42, 1991-95) correspond to above-mean accumulation at most sites. Correlations of the accumulation-rate records with sea-level pressure (SLP) and the SOI suggest that accumulation near the ice divide and in the Ross drainage system may be associated with the midlatitudes. The post-1970 increase in accumulation coupled with strong SLP-accumulation-rate correlations near the coast suggests recent intensification of cyclonic activity in the Pine Island-Thwaites drainage system

Decommissionable concrete? Adsorption of radionuclides by removable bio-mineralised hydroxyapatite layers

Decomissioning of concrete infrastructure at nuclear sites after years of use can be problematic and dangerous due to high levels of radioactivity, penetration of contamination into concrete and potentially large volumes of contaminated material. The depth of contamination within concrete ranges from mm to cm and contain many radioactive isotopes types such as C, U, Pu, Sr and Cs. Before decommissioning, concrete structures must be surface decontaminated to minimize waste volumes and reduce hazard. Techniques normally applied involve mechanical scabbing/scraping and high pressure blasting of concrete to remove layers of contamination. These techniques are expensive, unsafe for workers, and risk the spread of radioactive contamination. In addressing the above issues, this project aims to develop a novel decommissionable concrete tailored for safe, rapid decommissioning with minimal waste. Previous work in our group has shown that under certain conditions, bacteria can make bio-mineralized hydroxyapatite (HAp) which form layers as surfaces on cement [1]. The Ca from the HAp can substitute for other cations and we hypothesize that this mechanism would be relevant for radioactive isotopes such as Sr2+ and Cs+ and UO22+, by bonding to PO43-. These HAp layers can be engineered for easy removal at the end of life. Our poster presents promising results of the first stage in developing the adsorptive layer of hydroxyapatite (HAp) and show its powerful adsorptive properties for ions such as Sr2+ and Cs+ with promise for UO22+

Three human cell types respond to multi-walled carbon nanotubes and titanium dioxide nanobelts with cell-specific transcriptomic and proteomic expression patterns

The growing use of engineered nanoparticles (NPs) in commercial and medical applications raises the urgent need for tools that can predict NP toxicity. We conducted global transcriptome and proteome analyses of three human cell types, exposed to two high aspect ratio NP types, to identify patterns of expression that might indicate high vs. low NP toxicity. Three cell types representing the most common routes of human exposure to NPs, including macrophage like (THP-1), small airway epithelial (SAE), and intestinal (Caco-2/HT29-MTX) cells, were exposed to TiO2 nanobelts (TiO2-NB; high toxicity) and multi-walled carbon nanotubes (MWCNT; low toxicity) at low (10 μg/ml) and high (100 μg/ml) concentrations for 1 and 24 h. Unique patterns of gene and protein expressions were identified for each cell type, with no differentially expressed (p<0.05, 1.5-fold change) genes or proteins overlapping across all three cell types. While unique to each cell-type, the early response was primarily independent of NP type, showing similar expression patterns in response to both TiO2-NB and MWCNT. The early response might therefore indicate a general response to insult. In contrast, the 24 h response was unique to each NP type. The most significantly (p<0.05) enriched biological processes in THP-1 cells indicated TiO2-NB regulation of pathways associated with inflammation, apoptosis, cell cycle arrest, DNA replication stress and genomic instability, while MWCNT regulated pathways indicating increased cell proliferation, DNA repair and anti-apoptosis. These two distinct sets of biological pathways might therefore underlie cellular responses to high and low NP toxicity, respectively

Electrical lithosphere beneath the Kaapvaal craton, southern Africa

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 116 (2011): B04105, doi:10.1029/2010JB007883.A regional-scale magnetotelluric (MT) experiment across the southern African Kaapvaal craton and surrounding terranes, called the Southern African Magnetotelluric Experiment (SAMTEX), has revealed complex structure in the lithospheric mantle. Large variations in maximum resistivity at depths to 200–250 km relate directly to age and tectonic provenance of surface structures. Within the central portions of the Kaapvaal craton are regions of resistive lithosphere about 230 km thick, in agreement with estimates from xenolith thermobarometry and seismic surface wave tomography, but thinner than inferred from seismic body wave tomography. The MT data are unable to discriminate between a completely dry or slightly “damp” (a few hundred parts per million of water) structure within the transitional region at the base of the lithosphere. However, the structure of the uppermost ∼150 km of lithosphere is consistent with enhanced, but still low, conductivities reported for hydrous olivine and orthopyroxene at levels of water reported for Kaapvaal xenoliths. The electrical lithosphere around the Kimberley and Premier diamond mines is thinner than the maximum craton thickness found between Kimberley and Johannesburg/Pretoria. The mantle beneath the Bushveld Complex is highly conducting at depths around 60 km. Possible explanations for these high conductivities include graphite or sulphide and/or iron metals associated with the Bushveld magmatic event. We suggest that one of these conductive phases (most likely melt-related sulphides) could electrically connect iron-rich garnets in a garnet-rich eclogitic composition associated with a relict subduction slab.In addition to the funding and logistical support provided by SAMTEX consortium members, this work is also supported by research grants from the National Science Foundation (EAR‐0309584 and EAR‐0455242 through the Continental Dynamics Program), the Department of Science and Technology, South Africa, and Science Foundation of Ireland (grant 05/RFP/ GEO001)

Hydroxyapatite coatings on cement paste as barriers against radiological contamination

A novel method for precipitating hydroxyapatite (HAp) onto cement paste is investigated for protecting concrete infrastructure from radiological contamination. Legacy nuclear sites contain large volumes of contaminated concrete and are expensive and dangerous to decommission. One solution is to ‘design for decommissioning’ by confining contaminants to a thin layer. Current layering methods, including paints or films, offer poor durability over plant lifespans. Here, we present a mineral-HAp-coated cement, which innovatively serves as a barrier layer to radioactive contaminants (e.g. Sr, U). HAp is shown to directly mineralise onto a cement paste block in a layer several microns thick via a two-step process: first, applying a silica-based scaffold onto a cement paste block; and second, soaking the resulting block in a PO4-enriched Ringer’s solution. Strontium ingression was tested on coated and uncoated cement paste (~ 40 × 40 × 40mm cement, 450 mL, 1000 mg L− 1 Sr) for a period of 1-week. While both coated and uncoated samples reduced the solution concentration of Sr by half, Sr was held within the HAp layer of coated cement paste and was not observed within the cement matrix. In the uncoated samples, Sr had penetrated further into the block. Further studies aim to characterise HAp before and after exposure to a range of radioactive contaminants and to develop a method for mechanical layer separation

Effect of Implementing Discharge Readiness Assessment in Adult Medical-Surgical Units on 30-Day Return to Hospital The READI Randomized Clinical Trial

Importance: The downward trend in readmissions has recently slowed. New enhancements to hospital readmission reduction efforts are needed. Structured assessment of patient readiness for discharge has been recommended as an addition to discharge preparation standards of care to assist with tailoring of risk-mitigating actions. Objective: To determine the effect of unit-based implementation of readiness evaluation and discharge intervention protocols on readmissions and emergency department or observation visits. Design, Setting, and Participants: The Readiness Evaluation and Discharge Interventions (READI) cluster randomized clinical trial conducted in medical-surgical units of 33 Magnet hospitals between September 15, 2014, and March 31, 2017, included all adult (aged ≥18 years) patients discharged to home. Baseline and risk-adjusted intent-to-treat analyses used difference-in-differences multilevel logistic regression models with controls for patient characteristics. Interventions: Of 2 adult medical-surgical nursing units from each hospital, 1 was randomized to the intervention and 1 to usual care conditions. Using the 8-item Readiness for Hospital Discharge Scale, the 33 intervention units implemented a sequence of protocols with increasing numbers of components: READI1, in which nurses assessed patients to inform discharge preparation; READI2, which added patient self-assessment; and READI3, which added an instruction to act on a specified Readiness for Hospital Discharge Scale cutoff score indicative of low readiness. Main Outcomes and Measures: Thirty-day return to hospital (readmission or emergency department and observation visits). Intervention units above median baseline readmission rate (\u3e11.3%) were categorized as high-readmission units. Among the 33 intervention units, 17 were low-readmission units and 16 were high-readmission units. Results: The sample included 144 868 patient discharges (mean [SD] age, 59.6 [17.5] years; 51% female; 74 605 in the intervention group and 70 263 in the control group); 17 667 (12.2%) were readmitted and 12 732 (8.8%) had an emergency department visit or observation stay. None of the READI protocols reduced the primary outcome of return to hospital in intent-to-treat analysis of the full sample. In exploratory subgroup analysis, when patient self-assessments were combined with readiness assessment by nurses (READI2), readmissions were reduced by 1.79 percentage points (95% CI, −3.20 to −0.40 percentage points; P = .009) on high-readmission units. With nurse assessment alone and on low-readmission units, results were mixed. Conclusions and Relevance: Implemented in a broad range of hospitals and patients, the READI interventions were not effective in reducing return to hospital. However, adding a structured discharge readiness assessment that incorporates the patient’s own perspective to usual discharge care practices holds promise for mitigating high rates of return to the hospital following discharge