Investigation of electrode passivation during electrocoagulation treatment with aluminum electrodes for high silica content produced water

One of the main challenges for the implementation of electrocoagulation (EC) in water treatment are fouling and passivation of the electrodes, especially for applications with high contaminant concentrations. For the first time, we investigated in this study the process of fouling mitigation by polarity reversal during the EC treatment of boiler blowdown water from oil-sands produced water, characterized by high silica concentrations (0.5-4 g L^-1). This effluent is typically obtained from an evaporative desalination process in oil production industries. Potentiodynamic characterisation was used to study the impact of passivation on the anode dissolution. Although a charge loading of 4,800 C L^-1 was found to remove about 98% of silica from a 1 L batch of 4 g L^-1 Si solution, fouling reduced the performance significantly to about 40% in consecutive cycles of direct current EC (DC-EC) treatment. Periodic polarity reversal (PR) was found to reduce the amount of electrode fouling. Decreasing the polarity period from 60 to 10 s led to the formation of a soft powdery fouling layer that was easily removed from the electrodes. In contrast, with DC operation, a hard scale deposit was observed. The presence of organics in the field samples did not significantly affect the Si removal, and organics with high levels of oxygen and sulfate groups were preferentially removed. Detailed electrochemical and economic investigations suggest that the process operating at 85 °C achieves 95% silica removal (from an initial concentration of 481 mg L^-1) with an electrical energy requirement of 0.52 kWh m^-3, based on a charge loading of 1,200 C L^-1, an inter-electrode gap of 1.8 cm and a current density of 16 mA cm^-2.

Standardization in Quantitative Imaging: A Multicenter Comparison of Radiomic Features from Different Software Packages on Digital Reference Objects and Patient Data Sets

Radiomic features are being increasingly studied for clinical applications. We aimed to assess the agreement among radiomic features when computed by several groups by using different software packages under very tightly controlled conditions, which included standardized feature definitions and common image data sets. Ten sites (9 from the NCI's Quantitative Imaging Network] positron emission tomography–computed tomography working group plus one site from outside that group) participated in this project. Nine common quantitative imaging features were selected for comparison including features that describe morphology, intensity, shape, and texture. The common image data sets were: three 3D digital reference objects (DROs) and 10 patient image scans from the Lung Image Database Consortium data set using a specific lesion in each scan. Each object (DRO or lesion) was accompanied by an already-defined volume of interest, from which the features were calculated. Feature values for each object (DRO or lesion) were reported. The coefficient of variation (CV), expressed as a percentage, was calculated across software packages for each feature on each object. Thirteen sets of results were obtained for the DROs and patient data sets. Five of the 9 features showed excellent agreement with CV < 1%; 1 feature had moderate agreement (CV < 10%), and 3 features had larger variations (CV ≥ 10%) even after attempts at harmonization of feature calculations. This work highlights the value of feature definition standardization as well as the need to further clarify definitions for some features.

Higher consumption of red and processed meat is associated with adverse cardiovascular magnetic resonance morpho-functional phenotypes: A study of 19,408 UK Biobank participants

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Clinical Research Training Fellowship No. FS/17/81/33318 European Union’s Horizon 2020 research and innovation programme under grant agreement No 825903 (euCanSHare project).

Background

Multiple epidemiological studies link greater red and processed meat consumption with poorer cardiovascular outcomes. However, the impact of these exposures on directly measured cardiovascular phenotypes has not been examined in large cohorts. Limited existing studies suggest that the observed associations may be mediated by cardiometabolic diseases and/or novel mechanisms acting via the heart-gut axes. However, few studies systematically examine potential confounding and mediating mechanisms.

Purpose

We assessed, in the UK Biobank, the association between meat intake and cardiovascular structure and function incorporating a comprehensive range of confounders and mediators.

Methods

We studied 19,408 participants with cardiovascular magnetic resonance (CMR) data. We determined average daily red and processed meat intake using food frequency questionnaires. We used oily fish as a comparator linked to favourable cardiac health. We considered conventional CMR measures (ventricular volumes, left ventricular mass, ejection fraction, stroke volume), novel CMR radiomics features (shape, texture), and arterial stiffness metrics (arterial stiffness index, aortic distensibility). Multivariable linear regression models were used to investigate associations between meat/fish intake and cardiovascular phenotypes, adjusting for age, sex, deprivation, educational level, smoking, alcohol intake, and exercise. In separate models, we investigated the mediating role of cardiometabolic morbidities.

Results

Higher intake of red and processed meat was associated with an adverse overall pattern of right and left ventricular remodelling, poorer cardiac function, and higher arterial stiffness. Conversely, higher oily fish intake was associated with a healthy cardiovascular phenotype (better ventricular function, greater arterial compliance). Radiomics analysis showed association of the different dietary habits with unique overall geometry of the ventricles and myocardial texture. These associations were partially mediated by cardiometabolic morbidities.

Conclusions

Higher red and processed meat consumption is associated with adverse cardiovascular phenotypes. These relationships are not fully explained by mediation through cardiometabolic morbidities suggesting importance of alternative disease pathways. Understanding these potential novel disease mechanisms is important for optimising cardiovascular disease prevention strategies.

Characterization of marine microbial communities around an Arctic seabed hydrocarbon seep at Scott Inlet, Baffin Bay

Seabed hydrocarbon seeps present natural laboratories for investigating responses of marine ecosystems to petroleum input. A hydrocarbon seep near Scott Inlet, Baffin Bay, was visited for in situ observations and sampling in the summer of 2018. Video evidence of an active hydrocarbon seep was confirmed by methane and hydrocarbon analysis of the overlying water column, which is 260 m at this site. Elevated methane concentrations in bottom water above and down current from the seep decreased to background seawater levels in the mid-water column >150 m above the seafloor. Seafloor microbial mats morphologically resembling sulfide-oxidizing bacteria surrounded areas of bubble ebullition. Calcareous tube worms, brittle stars, shrimp, sponges, sea stars, sea anemones, sea urchins, small fish and soft corals were observed near the seep, with soft corals showing evidence for hydrocarbon incorporation. Sediment microbial communities included putative methane-oxidizing Methyloprofundus, sulfate-reducing Desulfobulbaceae and sulfide-oxidizing Sulfurovum. A metabolic gene diagnostic for aerobic methanotrophs (pmoA) was detected in the sediment and bottom water above the seep epicentre and up to 5 km away. Both 16S rRNA gene and pmoA amplicon sequencing revealed that pelagic microbial communities oriented along the geologic basement rise associated with methane seepage (running SW to NE) differed from communities in off-axis water up to 5 km away. Relative abundances of aerobic methanotrophs and putative hydrocarbon-degrading bacteria were elevated in the bottom water down current from the seep. Detection of bacterial clades typically associated with hydrocarbon and methane oxidation highlights the importance of Arctic marine microbial communities in mitigating hydrocarbon emissions from natural geologic sources.

Variation of cardiac magnetic resonance radiomics features by age and sex in healthy participants from the UK Biobank

Introduction

Cardiac magnetic resonance (CMR) radiomics use voxel-level data to derive quantitative indices of myocardial tissue texture, which may provide complementary risk information to traditional CMR measures.

Purpose

In this first stage of our work, establishing the performance characteristics of CMR radiomics in relation to disease outcomes, we aimed to elucidate differences in radiomic features by sex and age in apparently healthy adults.

Methods

We defined a healthy cohort from the first 5,065 individuals completing the UK Biobank Imaging Enhancement, limiting to white Caucasian ethnicity, and excluding those with major co-morbidities, or cardiovascular risk factors/symptoms. We created evenly distributed age groups: 45–54 years, 55–64 years, 65–74 years. Radiomics features were extracted from left ventricle segmentations, with normalisation to body surface area. We compared mean values of individual features between the sexes, stratified by age and separately between the oldest and youngest age groups for each sex.

Results

We studied 657 (309 men, 358 women) healthy individuals. There were significant differences between radiomics features of men and women. Different features appeared more important at different age groups. For instance, in the youngest age group “end-systolic coarseness” showed greatest difference between men and women, whilst “end-diastolic run percentage” and “end-diastolic high grey level emphasis” showed most variation in the oldest and middle age groups. In the oldest age groups, differences between men and women were most predominant in the texture features, whilst in the younger groups a mixture of shape and texture differences were observed. We demonstrate significant variation between radiomics features by age, these differences are exclusively in texture features with different features implicated in men and women (“end-diastolic mean intensity” in women, “end-systolic sum entropy in men”).

Conclusions

There are significant age and sex differences in CMR radiomics features of apparently healthy adults, demonstrating alterations in myocardial architecture not appreciated by conventional indices. In younger ages, shape and texture differences are observed, whilst in older ages texture differences dominate. Furthermore, texture features are the most different features between the youngest and oldest hearts. We provide proof-of-concept data indicating CMR radiomics has discriminatory value with regard to two characteristics strongly linked to cardiovascular outcomes. We will next elucidate relationships between CMR radiomics, cardiac risk factors, and clinical outcomes, establishing predictive value incremental to existing measures.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): European Union's Horizon 2020 research and innovation programme (825903),British Heart Foundation Clinical Research Training Fellowship (FS/17/81/33318)

Radiation hardness assessment of the charge-integrating hybrid pixel detector JUNGFRAU 1.0 for photon science

JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications in free electron lasers, particularly SwissFEL, and synchrotron light sources. JUNGFRAU is an automatic gain switching, charge-integrating detector which covers a dynamic range of more than 10(4) photons of an energy of 12 keV with a good linearity, uniformity of response, and spatial resolving power. The JUNGFRAU 1.0 application-specific integrated circuit (ASIC) features a 256 × 256 pixel matrix of 75 × 75 μm(2) pixels and is bump-bonded to a 320 μm thick Si sensor. Modules of 2 × 4 chips cover an area of about 4 × 8 cm(2). Readout rates in excess of 2 kHz enable linear count rate capabilities of 20 MHz (at 12 keV) and 50 MHz (at 5 keV). The tolerance of JUNGFRAU to radiation is a key issue to guarantee several years of operation at free electron lasers and synchrotrons. The radiation hardness of JUNGFRAU 1.0 is tested with synchrotron radiation up to 10 MGy of delivered dose. The effect of radiation-induced changes on the noise, baseline, gain, and gain switching is evaluated post-irradiation for both the ASIC and the hybridized assembly. The bare JUNGFRAU 1.0 chip can withstand doses as high as 10 MGy with minor changes to its noise and a reduction in the preamplifier gain. The hybridized assembly, in particular the sensor, is affected by the photon irradiation which mainly shows as an increase in the leakage current. Self-healing of the system is investigated during a period of 11 weeks after the delivery of the radiation dose. Annealing radiation-induced changes by bake-out at 100 °C is investigated. It is concluded that the JUNGFRAU 1.0 pixel is sufficiently radiation-hard for its envisioned applications at SwissFEL and synchrotron beam lines.

Rehabilitation for shoulder instability

Both structural and non-structural components can contribute to shoulder instability. Classification and therefore management must recognise these factors to achieve functional stability. This paper discusses a classification system proposing three types of shoulder instability recognising the structural and non-structural components and that a continuum exists between pathologies. Structural causes can be addressed with surgical intervention, but non-structural causes such as altered neuromuscular control within the rotator cuff should be addressed conservatively. The purpose of this article is to describe the types of instability and guide appropriate management, helping to avoid surgery in inappropriate cases and ensure that effective rehabilitation has been achieved.

PolLux: a new facility for soft x-ray spectromicroscopy at the Swiss Light Source

We report on the successful installation and operation of a scanning transmission x-ray microspectroscope (STXM) at the PolLux facility at the Swiss Light Source. This integration of an advanced STXM with improved sample handling capabilities and a novel beamline provides unique capabilities. PolLux uses linearly or circularly polarized x-rays from a bending magnet with an extended photon energy range (200-1400 eV). It is therefore well suited to determine a sample's quantitative chemical composition, molecular orientation, or thickness of organic as well as condensed matter materials. The local magnetic state of magnetic thin films is accessible through fast helicity switching by steering the electron beam off axis through the bending magnet. Ex vacuo girder movers allow fast and highly reproducible (<1 microm) alignment of the instrument with respect to the photon beam. The present spatial resolution is approximately 20 nm, limited by the zone plates utilized. The instrument has the stability and positional resolution to operate with much higher resolution optics as it becomes available. In addition to characterization experiments, we present several typical examples from materials research and environmental science to exemplify the capabilities.

[Does the structure of medical services affect the proportion of death in hospitals? An ecological analysis in the mobility regions of Switzerland?]

OBJECTIVES

With the discussion about measures to reduce over-capacities in the health services in mind, we examined the influence of medical supply structures and services on hospital utilisation directly before death.

METHODS

Based on the specification of the place of dying from the death certificates, we determined the proportions of deaths in hospitals in an ecological study. We analysed deaths of persons above age 65 in each of the 106 mobility regions of Switzerland in the years 1979 to 1980.

RESULTS

The proportion of deaths occurring in hospitals varied between 27% and 81%. Despite missing data regarding stationary and ambulatory care services, more than half of the variance could be explained by means of a multivariate regression analysis. Our results imply an inverse relation between the proportion of deaths in the hospital and the number of consultations provided by primary care physicians, as well as the number of nursing home beds. Further, we observe a direct relation to the number of hospital beds in a region. All indicators are calculated per inhabitant.

CONCLUSIONS

In health care supply planning, such systematic associations should be taken into account. We recommend to analyse regularly interregional differences in supply and outcome of medical performances with the best available data.