The evolution of the martian core is widely assumed to mirror the characteristics observed for Earth's core. Data from experiments performed on iron-sulfur and iron-nickel-sulfur systems at pressures corresponding to the center of Mars indicate that its core is presently completely liquid and that it will not form an outwardly crystallizing iron-rich inner core, as does Earth. Instead, planetary cooling will lead to core crystallization following either a "snowing-core" model, whereby iron-rich solids nucleate in the outer portions of the core and sink toward the center, or a "sulfide inner-core" model, where an iron-sulfide phase crystallizes to form a solid inner core.

[1] Phosphorus is an important element believed to be present in the Earth's core. As a non-metal, its solubility in iron is limited, leading to the precipitation of phosphides at high concentrations. Here we present experimental results for the iron-rich portions of the Fe-P and Fe-P-S systems at 23 GPa. We find a Fe-P eutectic point occurring at 9 wt% P and 1275°C at 23 GPa. Up to 4 wt% P is soluble in the Fe-rich solid coexisting with the eutectic liquid at these conditions. The ternary Fe-P-S system displays a simple cotectic between the Fe-P and Fe-S binary eutectics with minimum melting temperature on the S-side at 1075°C. At subsolidus conditions there is complete solid solution between Fe 3 P and Fe 3 S. The high solubility of phosphorus in iron along with its miscibility in Fe 3 S and iron-sulfur liquids at high pressures, combined with expectation of only minor concentrations in planetary cores, indicate phosphorus will not form a distinct phase within terrestrial planet cores.

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Objectives Schizophrenia is characterized by high levels of disability often resulting in increased healthcare utilization and spending. With expanding healthcare costs across all healthcare sectors, there is a need to understand how healthcare spending has changed over time. We conducted a population-based study using administrative health data from Alberta, Canada, to describe changes in medical complexity and direct healthcare spending among patients with schizophrenia over a 10-year period. Methods A serial cross-sectional study from January 1, 2008, to December 31, 2017, was conducted to determine changes in demographic characteristics, medical complexity, and costs among all adults (18 years or older) with schizophrenia. Total healthcare spending and sector-specific costs attributable to hospitalizations, emergency department visits, practitioner billings, and prescriptions were calculated and compared over time. Results Over the 10-year period the contact prevalence of patients with schizophrenia increased from 0.6% ( n  =  16,183) to 1.0% ( n  =  33,176) within the province. There was a marked change in medical complexity with the number of patients living with 3 or more comorbidities increasing from 33.0% to 47.3%. Direct annual healthcare costs increased 2-fold from 321 to 639 million CAD (493 million USD) with a 7-fold increase in medication expenditures over the 10-year time frame. As of 2017, spending on pharmaceutical treatment surpassed hospitalizations as the leading spending category in this population. Conclusions Healthcare spending among patients with schizophrenia continues to increase and may be partially attributable to growing rates of multimorbidity within this population. Although promising second-generation antipsychotic medications have entered the market, this has resulted in considerable changes in the distribution of healthcare spending over time. These findings will inform policy discussions around resource allocation and efforts to curb health spending while also improving care for patients with schizophrenia.

Introduction Understanding the reasons for the wide variation in health care spending among patients with schizophrenia may benefit the development of interventions aimed at improving patient outcomes and health care spending efficiency. The aim of our study was to determine factors associated with high health care spending in the patient population. Methods A serial cross­sectional study used the administrative health records of residents of Alberta, Canada between 1 January 2008 and 31 December 2017 and provincial costing methodologies to calculate total health care spending and sector­specific costs. Factors that modified the odds of being a high cost (i.e. 95th percentile or higher) patient with schizophrenia were estimated using generalized estimating equations. Results This study captured 242 818 person­years of observations among 38 177 unique patients with schizophrenia. Increased odds of being a high­cost patient were associated with younger age (18–29 years), male sex, unstable housing status and requiring care from multiple medical specialties. The strongest estimated associations between high cost status and comorbidity were for metastatic cancer (OR = 2.26) and cirrhosis (OR = 2.07). In contrast, polypharmacy was associated with a decreased odds of being high cost compared with untreated patients. Conclusion Factors associated with being a high­cost patient are the result of complex interactions between individual, structural and treatment­related factors. Efforts to improve patient outcomes and address rising health care costs must consider the value of allocating resources towards early detection and support of patients with schizophrenia along with the prevention/management of comorbidity.

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A small proportion of patients account for a disproportionate amount of health care spending in developed countries with advanced health care systems. Specifically, patients in the top 1% of health care spending in North America account for 25% to 40% of total health care expenditures in a given year. 1,2 Increasing age, receipt of end-of-life care, multimorbidity, mental health conditions and social disadvantage are each associated with high-cost health system use. 2 However, the heterogeneous nature of this patient population makes it difficult to develop and implement strategies to improve care and curb health care spending for all high-needs, high-cost patients. 3,4 Further complicating this goal, two-thirds of the high-cost population in a given fiscal year are not high-cost in the following year, making it difficult to identify the appropriate target population for intervention. 1

Moisture-assisted crack growth at polymer/glass interfaces was measured as a function of applied strain energy release rate using a four-point flexure apparatus coupled with an inverted microscope. The specimens consisted of two glass plates bonded together with a thin layer of epoxy or epoxy acrylate adhesive. Of particular importance in this study was the growth of cracks on both interfaces of the sample. Finite element analysis was carried out to gain a fundamental understanding of the observed crack growth behavior.