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Induced abortion is an indicator of access to, and quality of reproductive healthcare, but rates are relatively unknown in women with schizophrenia.
We examined whether women with schizophrenia experience increased induced abortion compared with those without schizophrenia, and identified factors associated with induced abortion risk.
In a population-based, repeated cross-sectional study (2011–2013), we compared women with and without schizophrenia in Ontario, Canada on rates of induced abortions per 1000 women and per 1000 live births. We then followed a longitudinal cohort of women with schizophrenia aged 15–44 years (n = 11 149) from 2011, using modified Poisson regression to identify risk factors for induced abortion.
Women with schizophrenia had higher abortion rates than those without schizophrenia in all years (15.5–17.5 v. 12.8–13.6 per 1000 women; largest rate ratio, 1.33; 95% CI 1.16–1.54). They also had higher abortion ratios (592–736 v. 321–341 per 1000 live births; largest rate ratio, 2.25; 95% CI 1.96–2.59). Younger age (<25 years; adjusted relative risk (aRR), 1.84; 95% CI 1.39–2.44), multiparity (aRR 2.17, 95% CI 1.66–2.83), comorbid non-psychotic mental illness (aRR 2.15, 95% CI 1.34–3.46) and substance misuse disorders (aRR 1.85, 95% CI 1.47–2.34) were associated with increased abortion risk.
These results demonstrate vulnerability related to reproductive healthcare for women with schizophrenia. Evidence-based interventions to support optimal sexual health, particularly in young women, those with psychiatric and addiction comorbidity, and women who have already had a child, are warranted.
Despite decades of trials, the prognosis for diffuse intrinsic pontine gliomas (DIPG) remains dismal. DIPG is inoperable and standard treatment is radiation alone, as the addition of chemotherapeutic agents, such as temozolomide, have not improved survival. In addition to inherent chemoresistance, treatment of DIPG is impeded by an intact blood-brain barrier (BBB). VAL-083 is a structurally unique bi-functional DNA-targeting agent that readily crosses the BBB. VAL-083 forms interstrand DNA crosslinks at N7-guanine, resulting in DNA double-strand breaks (DSB), S/G2-phase cell-cycle arrest, and ultimately cancer cell death. We have previously demonstrated that VAL-083 is able to overcome temozolomide-resistance in vitro and in vivo, and that its cytotoxicity is independent of the DNA-repair enzyme O6-methylguanine DNA-methyltransferase (MGMT). MGMT is almost universally expressed in DIPG and its expression is strongly correlated with temozolomide-resistance. VAL-083’s distinct mechanism-of-action suggests the potential for combination with inhibitors of DNA DSB repair or S/G2 cell-cycle progression (e.g. Wee1 inhibitor AZD1775). Here, we investigated the effects of VAL-083 in combination with radiation, AZD1775 or irinotecan (topoisomerase inhibitor) in three DIPG cell-lines: SF10693 (H3.1), SF8628 (H3.3) and NEM157 (H3.3). VAL-083 showed activity at low uM-concentration in all three cell-lines. In addition, VAL-083 showed synergy with AZD1775 in all three cell-lines. Combined with its ability to cross the BBB, accumulate in brain tumor tissue and overcome MGMT-related chemoresistance, these results suggest VAL-083 as a potentially attractive treatment option for DIPG as single agent or in combination with AZD1775. Combination studies with radiation are ongoing and will be presented at the meeting.
Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
Defining the structural style of fold-and-thrust belts is an important step for understanding the factors that control their long- and short-term dynamics, for comprehending seismic hazard associated with them, and for assessing their economic potential. While the thin-skinned model (no basement involvement) has long been the driving methodology for cross section construction and restoration of foreland fold-and-thrust belts, a wealth of new geological and geophysical studies have shown that they are often thick-skinned, that is, basement-involved.
This paper presents a theory of the labor market matching process in terms of incentive-based, two-sided search among heterogeneous agents. The matching process is decomposed into its two component stages: the contact stage, in which job searchers make contact with employers, and the selection stage, in which they decide whether to match. We construct a theoretical model explaining two-sided selection through microeconomic incentives. Firms face adjustment costs in responding to heterogeneous variations in the characteristics of workers and jobs. Matches and separations are described through firms' job offer and firing decisions and workers' job acceptance and quit decisions. Our calibrated model for the United States can account for important empirical regularities, such as the large volatilities of labor market variables, that the conventional matching model cannot.
We report the initial results of modelling studies performed on the Dounreay Database of Spent Nuclear fuel particles recovered from the marine environment and coastal foreshore adjacent to the Dounreay Fast Reactor Complex located in the North East coast of Scotland. We demonstrate how interrogation of the fuel-particle frequency versus 137Cs isotopic distribution allows us to generate particle behaviour models and residence lifetimes of various particle subgroups. Similarly we find the recovered fuel particle's spatial distribution and shape characteristics are determined by environmental selection rules governed by properties of adjacent sediment and sediment transport mechanisms.
Analysis of the Spent Fuel particle database allows us to speculate on the original Site discharge pathways and fuel composition at the time of discharge. Further such studies correlate well with other sample morphology and compositional data and allow us to speculate upon the ultimate fate of different spent fuel types.
Sand-sized particles of spent nuclear fuel have been found in the environment at Dounreay, north Scotland. These particles, believed to have been discharged during early stages of site operations in the 1960s, have been recovered from areas within the Site, coastal foreshore adjacent to the Site and offshore (marine) environments. As part of the Dounreay Site Restoration Plan, a significant program of work is being undertaken to establish the fate of the Dounreay particles in the marine environment. This program includes materials analysis of particles and particle analogues
The diverse depositional environments, coupled to relatively long fuel-particle residence times, allow insight to be gained into the behaviour of the particles in the natural environment. This includes the effects of physical, chemical and mechanical processes such as particle erosion and corrosion, particle abrasion and particle-saltwater interaction. Using materials analysis techniques including Scanning Electron Microscopy, Energy Dispersive X-Ray Analysis, Electron Probe Microanalysis, together with 137Cs activity measurement we review the fuel-particle mechanical and chemical stability and current radio-isotope composition. These studies allows us to identify the fuel provenance, fuel treatment history and draw some general conclusions of the ultimate fuel particle residence time. We demonstrate that radioisotope modelling strongly indicates that particle break-up is limited by the chemical effects of the marine environment coupled with the native oxide films present on the metallic fuel. Particle transport and distribution are governed by environmental effects on the sediment and sediment transport mechanisms such as tidal currents and storm events.
This study is unique in that it involves the potential effects of long-term saltwater and abrasion interactions with fuel matrixes containing both U-Al and U-Mo of which there is little literature available.
The compatibility of inorganic materials with living tissues and biological compounds is crucial in many areas, including medical diagnostics, biosensors, drug delivery, etc. In this work, we are interested in the interaction of living mammalian cells with semiconductor surfaces for novel thin-film biosensor devices. Amorphous silicon may give advantages over crystalline silicon for some devices because of its large-area, low-temperature compatibility, and its large optical absorption coefficient in the visible spectrum. Amorphous silicon thin films (500Å) deposited on quartz glass were cleaned using ambient UV/O3 treatment, leaving the surface largely OH-terminated and hydrophilic. The hydrophilic surface was then exposed to a vapor of octyltrichlorosilane (CH3(CH2)7SiCl3, OTS). The resulting surface was strongly hydrophobic, with advancing contact angles with water <106°. This organic surface was masked to reserve areas of uncoated hydrophilic substrate, and placed in a cell culture (BHK-21 cells) to observe cell adhesion and proliferation. A high degree of cell attachment was observed on the UV/O3-treated surfaces (~400 cells/mm2) compared to ~450 cells/mm2 on the culture dish control surface, indicating cell proliferation and growth. Little cell adhesion occurred on the hydrophobic organiccoated surface (~40 cells/mm2), and the cells remained round and only minimally attached. On masked surfaces, the organic-free areas showed dense, well-adhered cell growth while the coated areas showed much fewer and rounded cells. On all samples as well as control surfaces, cell death was <1%. These results suggest a means for selectively controlling cell adhesion to thin film electronic device surfaces, through the patterning of hydrophobic surface coatings.
In this paper, we propose the design and fabrication of buried silicon optical interconnect technology, the sub-surface silicon optical bus (S3B). The proposed approach relies on engineering the dispersion properties of embedded silicon three-dimensional photonic crystals to create sub-micron routing channels and control light propagation. Further, we present a method for the fabrication of buried three-dimensional (3D) photonic-crystal structures using conventional planar silicon micromachining. The method utilizes a single planar etch mask coupled with time-multiplexed, sidewall-passivating, deep anisotropic reactive-ion etching, to create an array of spherical voids with three-dimensional symmetry. Preliminary results are presented that demonstrate the feasibility of realizing chip-scale optical interconnects using our proposed approach.
The appropriate application of multilayers as x-ray dispersion devices requires that their diffraction characteristics be understood. Conventional models, based on perfect-crystal and mosaic-crystal theories, predict diffraction efficiencies (integral reflection coefficients) significantly larger than values measured experimentally. It has been shown that introduction of surface roughness effects into the model can promote agreement between experimental and theoretical values, while the presence of other types of defects produce changes too small in magnitude to explain the discrepancy. Because it is reasonably well agreed that the resolving power of multilayers is only moderate, compared to the more conventional “crystal” dispersing devices, it is important to be able to predict or measure that parameter in order to assess the usefulness for a particular application. Experimental measurements and theoretical calculations have been carried out on multilayers (almost exclusively tungsten/carbon) prepared to have 2d-spacings from 50 to 140A. The experimental work used both singlecrystal and double-crystal spectrometers; the calculations used the crystal diffraction model, as modified to include surface roughness.
The Vault Model has been developed to assess the performance of engineered barriers in a conceptual geological disposal vault for used nuclear fuel. It represents container failure, release of radionuclides from used fuel and mass transport of released radionuclides through the clay-based sealing materials surrounding the waste containers. This paper focusses on mass-transport processes represented by the Vault Model, including diffusion, convection and retardation.
In particular, we present results of several scoping calculations carried out with the Vault Model. We consider cases where the clay-based barriers are represented by either a one- or a two-layer system adjacent to an intact rock and a case where the two clay-based barriers are adjacent to a highly fractured rock. These calculations provide insight into the model and produce test cases for comparison with both relatively simple analytical estimates and similar computer codes, as they become available. The analytical estimates generally support the Vault Model results and thus enhance our confidence in the accuracy of the Vault Model calculations.
A kinetic model for the dissolution of borosilicate glass, incorporated into the EQ3/6 geochemical modeling code, is used to predict the dissolution rate of a nuclear waste glass. In the model, the glass dissolution rate is controlled by the rate of dissolution of an alkalidepleted amorphous surface (gel) layer. Assuming that the gel layer dissolution affinity controls glass dissolution rates is similar to the silica saturation concept of Grambow  except that our model predicts that all components concentrated in the surface layer, not just silica, affect glass dissolution rates. The good agreement between predicted and observed elemental dissolution rates suggests that the dissolution rate of the gel layer limits the overall rate of glass dissolution. The model predicts that the long-term rate of glass dissolution will depend mainly on ion concentrations in solution, and therefore on the secondary phases which precipitate and control ion concentrations.
The optical properties of TexSe(1−x) were studied for x = 0.8, 0.9, and 1.0. The results for variable temperature, polarization sensitive, spectral photoconductivity measurements on oriented single crystals, as well as the energy band gaps and their temperature dependencies are presented. In all cases, the band gap was found to increase with increasing temperature. Analytical expressions describing the temperature dependent behavior are reported. Furthermore, for the first time the characteristic two peak spectrum of tellurium was separated into its two components for incident radiation polarized parallel and perpendicular to the c-axis as a function of temperature. However, two distinct peaks were not discernible in the alloys, with or without polarization, although the signal intensity was slightly polarization dependent.