Ceramics in the solid solution system, (1 − x)Ba0.8Ca0.2TiO3–xBi(Mg0.5Ti0.5)O3, were prepared by a conventional mixed oxide route. Single‐phase perovskite‐type X‐ray diffraction patterns were ...observed for compositions x < 0.6. A change from tetragonal to single‐phase cubic X‐ray patterns occurred at x ≥ 0.1. Dielectric measurements indicated relaxor behavior for x ≥ 0.1. Increasing the Bi(Mg0.5Ti0.5)O3 content improved the temperature sensitivity of relative permittivity ϵr at high temperatures. At x = 0.5, a near‐plateau relative permittivity, 835 ± 40, extended across the temperature range, 65°C–550°C; the permittivity increased at x = 0.6 to 2170 ± 100 for temperatures 160°C–400°C (1 kHz). The corresponding loss tangent, tanδ, was ≤0.025 for temperatures between 100°C and 430°C for composition x = 0.5; at x = 0.6, losses increased sharply at >300°C. Comparisons of dielectric properties with other materials proposed for high‐temperature capacitor applications suggest that (1 − x)Ba0.8Ca0.2TiO3–xBi(Mg0.5Ti0.5)O3 ceramics are a promising base material for further development.
Ferroelectric/antiferroelectric thin/thick films with large positive or negative electrocaloric (EC) effects could be very useful in designing commercial refrigeration devices. Here, a giant negative ...EC effect (maximum Δ
T
∼ −42.5 K with Δ
S
∼ −29.3 J K
−1
kg
−1
) comparable to the best positive EC effects reported so far is demonstrated for 0.5(Ba
0.8
Ca
0.2
)TiO
3
-0.5Bi(Mg
0.5
Ti
0.5
)O
3
(BCT-BMT) lead-free relaxor ferroelectric thin films prepared on Pt(111)/TiO
x
/SiO
2
/Si substrates using a sol-gel method. An electric-field induced structural phase transition (nanoscale tetragonal and orthorhombic to rhombohedral) along the out-of-plane 111 direction plays a very key role in developing the giant negative EC effect. This breakthrough will pave the way for practical applications of next-generation refrigeration devices with high cooling efficiency in one cycle by ingeniously utilizing and combining both the giant negative and positive EC effects. Moreover, a large energy density of 51.7 J cm
−3
with a high power density of 1.15 × 10
10
W kg
−1
at room temperature is also achieved in the thin film, indicating that it is also an attractive multifunctional material for energy storage.
Ferroelectric/antiferroelectric thin/thick films with large positive or negative electrocaloric (EC) effects could be very useful in designing commercial refrigeration devices.
Summary Background Androgen-deprivation therapy is offered to men with prostate cancer who have a rising prostate-specific antigen after curative therapy (PSA relapse) or who are considered not ...suitable for curative treatment; however, the optimal timing for its introduction is uncertain. We aimed to assess whether immediate androgen-deprivation therapy improves overall survival compared with delayed therapy. Methods In this randomised, multicentre, phase 3, non-blinded trial, we recruited men through 29 oncology centres in Australia, New Zealand, and Canada. Men with prostate cancer were eligible if they had a PSA relapse after previous attempted curative therapy (radiotherapy or surgery, with or without postoperative radiotherapy) or if they were not considered suitable for curative treatment (because of age, comorbidity, or locally advanced disease). We used a database-embedded, dynamically balanced, randomisation algorithm, coordinated by the Cancer Council Victoria, to randomly assign participants (1:1) to immediate androgen-deprivation therapy (immediate therapy arm) or to delayed androgen-deprivation therapy (delayed therapy arm) with a recommended interval of at least 2 years unless clinically contraindicated. Randomisation for participants with PSA relapse was stratified by type of previous therapy, relapse-free interval, and PSA doubling time; randomisation for those with non-curative disease was stratified by metastatic status; and randomisation in both groups was stratified by planned treatment schedule (continuous or intermittent) and treatment centre. Clinicians could prescribe any form and schedule of androgen-deprivation therapy and group assignment was not masked. The primary outcome was overall survival in the intention-to-treat population. The trial closed to accrual in 2012 after review by the independent data monitoring committee, but data collection continued for 18 months until Feb 26, 2014. It is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12606000301561) and ClinicalTrials.gov ( NCT00110162 ). Findings Between Sept 3, 2004, and July 13, 2012, we recruited 293 men (261 with PSA relapse and 32 with non-curable disease). We randomly assigned 142 men to the immediate therapy arm and 151 to the delayed therapy arm. Median follow-up was 5 years (IQR 3·3–6·2) from the date of randomisation. 16 (11%) men died in the immediate therapy arm and 30 (20%) died in the delayed therapy arm. 5-year overall survival was 86·4% (95% CI 78·5–91·5) in the delayed therapy arm versus 91·2% (84·2–95·2) in the immediate therapy arm (log-rank p=0·047). After Cox regression, the unadjusted HR for overall survival for immediate versus delayed arm assignment was 0·55 (95% CI 0·30–1·00; p=0·050). 23 patients had grade 3 treatment-related adverse events. 105 (36%) men had adverse events requiring hospital admission; none of these events were attributable to treatment or differed between treatment-timing groups. The most common serious adverse events were cardiovascular, which occurred in nine (6%) patients in the delayed therapy arm and 13 (9%) in the immediate therapy arm. Interpretation Immediate receipt of androgen-deprivation therapy significantly improved overall survival compared with delayed intervention in men with PSA-relapsed or non-curable prostate cancer. The results provide benchmark evidence of survival rates and morbidity to discuss with men when considering their treatment options. Funding Australian National Health and Medical Research Council and Cancer Councils, The Royal Australian and New Zealand College of Radiologists, Mayne Pharma Australia.
In clinical oncology, many diagnostic tasks rely on the identification of cells in histopathology images. While supervised machine learning techniques necessitate the need for labels, providing ...manual cell annotations is time-consuming. In this paper, we propose a self-supervised framework (enVironment-aware cOntrastive cell represenTation learning: VOLTA) for cell representation learning in histopathology images using a technique that accounts for the cell's mutual relationship with its environment. We subject our model to extensive experiments on data collected from multiple institutions comprising over 800,000 cells and six cancer types. To showcase the potential of our proposed framework, we apply VOLTA to ovarian and endometrial cancers and demonstrate that our cell representations can be utilized to identify the known histotypes of ovarian cancer and provide insights that link histopathology and molecular subtypes of endometrial cancer. Unlike supervised models, we provide a framework that can empower discoveries without any annotation data, even in situations where sample sizes are limited.
Sorption-enhanced steam reforming (SESR) is an energy and cost efficient approach to produce hydrogen with high purity. SESR makes it economically feasible to use a wide range of feedstocks for ...hydrogen production such as methane, ethanol, and biomass. Selection of catalysts and sorbents plays a vital role in SESR. This article reviews the recent research aimed at process intensification by the integration of catalysis and chemisorption functions into a single material. Alkali metal ceramic powders, including Li2ZrO3, Li4SiO4 and Na2ZrO3 display characteristics suitable for capturing CO2 at low concentrations (<15% CO2) and high temperatures (>500 °C), and thus are applicable to precombustion technologies such as SESR, as well as postcombustion capture of CO2 from flue gases. This paper reviews the progress made in improving the operational performance of alkali metal ceramics under conditions that simulate power plant and SESR operation, by adopting new methods of sorbent synthesis and doping with additional elements. The paper also discusses the role of carbonates formed after in situ CO2 chemisorption during a steam reforming process in respect of catalysts for tar cracking.
A number of relaxor ferroelectric ceramics have been demonstrated to possess a near stable value of relative permittivity over very wide temperature ranges. This cannot be explained by conventional ...theories of relaxors. One such system is based on the perovskite solid solution series: (1-x) (Ba0.8Ca0.2)TiO3-xBi(Mg0.5Ti0.5)O3, giving stable relative permittivity from 150 to 500 °C. We show by scanning transmission electron microscopy and electron energy loss spectroscopic elemental mapping that nanoscale compositional segregation occurs in the temperature stable relaxor composition (x = 0.55), with Ba/Ti clusters some 2–4 nm in extent, separated by Bi-rich regions of comparable size. This nanomosaic structure is consistent with phase separation into a ferroelectrically active BaTiO3 – type phase (Ba/Ti rich) and a weakly polar Bi/(Mg) rich perovskite solid solution. The possibility that nanophase segregation is the cause of weak dipole coupling and suppression of the dielectric relaxation peak is considered.
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The origins of distinctive compositional dependence of relative permittivity, ɛr, in the Pb-free piezoelectric system (1−x) Na0.5K0.5NbO3–xLiTaO3, x⩽10mol.% modified with BiScO3 have been revealed ...using transmission electron microscopy with energy dispersive X-ray analysis (TEM-EDX). As the LiTaO3 content increased the Curie peak at ∼370°C in ɛr–T plots became more diffuse, and at x=5mol.% an additional higher temperature peak occurred. TEM-EDX analysis showed the change in dielectric properties at x=5mol.% was due to a change in microstructure: micron-scale grains were replaced by submicron grains exhibiting core–shell chemical segregation. The outer shell was similar to the target solid solution composition, slightly enriched in Bi, Sc and Ta, whilst the core approximated to (Na, K, Li)NbO3 and was responsible for the additional dielectric peak. Examples of a novel three-tier metastable grain structure were observed for certain compositions.
Extra-cranial malignant rhabdoid tumors (MRTs) and cranial atypical teratoid RTs (ATRTs) are heterogeneous pediatric cancers driven primarily by SMARCB1 loss. To understand the genome-wide molecular ...relationships between MRTs and ATRTs, we analyze multi-omics data from 140 MRTs and 161 ATRTs. We detect similarities between the MYC subgroup of ATRTs (ATRT-MYC) and extra-cranial MRTs, including global DNA hypomethylation and overexpression of HOX genes and genes involved in mesenchymal development, distinguishing them from other ATRT subgroups that express neural-like features. We identify five DNA methylation subgroups associated with anatomical sites and SMARCB1 mutation patterns. Groups 1, 3, and 4 exhibit cytotoxic T cell infiltration and expression of immune checkpoint regulators, consistent with a potential role for immunotherapy in rhabdoid tumor patients.
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•MYC subgroup of cranial RTs (ATRT-MYC) is molecularly similar to extra-cranial RTs•Five DNA methylation subgroups are identified in RTs across multiple organ sites•Groups 1, 3, and 4 exhibit cytotoxic T cell infiltration and PD1 and PD-L1 expression
Chun et al. report similarities between the MYC subgroup of cranial and extra-cranial rhabdoid tumors (RTs) at genetic, gene-expression, and epigenetic levels. They identify five DNA methylation subgroups of RTs across multiple organ sites, and some subgroups exhibit increased levels of immune cell infiltration and immune checkpoint expression.
Powders of CaO sorbent modified with CaZrO3 have been synthesized by a wet chemical route. For carbonation and calcination conditions relevant to sorbent-enhanced steam reforming applications, a ...powder of composition 10 wt % CaZrO3/90 wt % CaO showed an initial rise in CO2 uptake capacity in the first 10 carbonation–decarbonation cycles, increasing from 0.31 g of CO2/g of sorbent in cycle 1 to 0.37 g of CO2/g of sorbent in cycle 10 and stabilizing at this value for the remainder of the 30 cycles tested, with carbonation at 650 °C in 15% CO2 and calcination at 800 °C in air. Under more severe conditions of calcination at 950 °C in 100% CO2, following carbonation at 650 °C in 100% CO2, the best overall performance was for a sorbent with 30 wt % CaZrO3/70 wt % CaO (the highest Zr ratio studied), with an initial uptake of 0.36 g of CO2/g of sorbent, decreasing to 0.31 g of CO2/g of sorbent at the 30th cycle. Electron microscopy revealed that CaZrO3 was present in the form of ≤0.5 μm cuboid and 20–80 nm particles dispersed within a porous matrix of CaO/CaCO3; the nanoparticles are considered to be the principal reason for promoting multicycle durability.
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