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Amino acids are present in all known life, so identifying the environmental conditions under which they can be synthesized constrains where life on Earth might have formed and where life might be found on other planetary bodies. All known abiotic amino acid syntheses require ammonia, which is only produced in reducing and neutral atmospheres. Here, we demonstrate that the Fe-bearing hydroxide mineral ferroan brucite [Fe0.33,Mg0.67(OH)2] can mediate the reaction of nitrate and glyoxylate to form glycine, the simplest amino acid used in life. Up to 97% of this glycine was detected only after acid digestion of the mineral, demonstrating that it had been strongly partitioned to the mineral. The dicarboxylic amino acid 3-hydroxy aspartate was also detected, which suggests that reactants underwent a mechanism that simultaneously produced mono-and dicarboxylic amino acids. Nitrate can be produced in both neutral and oxidizing atmospheres, so reductive amination of nitrate and glyoxylate on a ferroan brucite surface expands origins of life scenarios. First, it expands the environmental conditions in which life's precursors could form to include oxidizing atmospheres. Second, it demonstrates the ability of ferroan brucite, an abundant, secondary mineral in serpentinizing systems where olivine is partly hydrated, to mediate reductive amination. Finally, the results demonstrate the need to consider mineral-bound products when analyzing samples for abiotic amino acid synthesis. [ABSTRACT FROM AUTHOR]

A two-turn D-shaped test coil with a height of 2.0 m and a width of 1.8 m is fabricated by a react-and-wind method by using a 20 kA Nb3Al cable-in-conduit (CIC) conductor. The total strain of the D-shaped test coil is about 0.57 percent, the same as the triplex-CIC sample fabricated by a W&R method, indicating that bending did not influence the I(sub c).

The effects of specimen size as well as notch size on longitudinal splitting failure in notched unidirectional carbon/epoxy laminates are examined. For this purpose, static tension tests are performed on thickness dimension (1D), in-plane dimensions (2D) and all the dimensions (3D) scaled notched specimens, respectively. The experimental results show that splitting strength has a tendency to increase by about 5-10% with increasing thickness dimension of a notched specimen. In contrast, splitting strength tends to decrease by about 20% not only with increasing in-plane dimensions but also with increasing all the dimensions, regardless of notch size. It is suggested that the 3D scaling effect in splitting strength of notched specimens is governed by the 2D scaling effect involved, since the 1D scaling effect is smaller. On the basis of these observations, a scale-sensitive notch size effect law is established. It is demonstrated to adequately describe the specimen-size effect as well as the notch-size effect in the longitudinal splitting strength of the unidirectional carbon/epoxy composite laminates. It is also shown that the effective normalized mode I fracture toughness for splitting failure in the unidirectional CFRP laminate can indirectly be evaluated by means of the scale-sensitive notch size effect law and it is close to the fracture mechanics test results in literature. [ABSTRACT FROM AUTHOR]

The effect of specimen size on tensile strength of a unidirectional carbon/epoxy laminate in the longitudinal direction is examined. For this purpose, static tension tests are performed on thickness dimension (1D), in-plane dimensions (2D), and all the dimensions (3D) scaled specimens, respectively. The experimental results show that the tensile strength has a tendency to decrease by about 40-60% with increasing thickness dimension by a factor of 2. In contrast, the tensile strength tends to increase by about 60-130% with increasing in-plane dimensions by a factor of 2. The tensile strength has a tendency to slightly increase by about 6% with increasing all the dimensions by a factor of 2. The effect of 1D scaling on the tensile strength is opposite to that of 2D scaling, and the 2D scaling effect is slightly more significant than the 1D scaling effect. The 2D scaling effect in the tensile strength masks the 1D scaling effect when they are involved at the same time. The latter is consistent with the small 3D scaling effect that is similar in nature to the 2D scaling effect. On the basis of these observations, a phenomenological equation to describe the effect of specimen size on the tensile strength of the unidirectional carbon/epoxy composite is established. It is demonstrated that the scale effect model can adequately describe the 1D, 2D, and 3D scaling effects on the tensile strength of the unidirectional composite. [ABSTRACT FROM AUTHOR]

The aim of this study was to measure the one-year total cost of strokes and to investigate the value of stroke care, defined as cost per QALY. The study population included 892 patients with first-ever acute strokes, hemorrhagic strokes, and ischemic strokes, (ICD-10 codes: I61, I63, and I64) admitted within 48 h of symptoms onset to nine public hospitals located in six cities. We conducted a bottom-up cost analysis from the societal point of view. All cost components including direct medical costs, productivity losses due to morbidity and mortality, and informal care costs were considered. We used an annual time horizon, including all costs for 2021, irrespective of the time of disease onset. The average cost (direct and indirect) was extrapolated in order to estimate the national annual burden associated with stroke. We estimated the total cost of stroke in Greece at EUR 343.1 mil. a year in 2021, (EUR 10,722/patient or EUR 23,308 per QALY). Out of EUR 343.1 mil., 53.3% (EUR 182.9 mil.) consisted of direct healthcare costs, representing 1.1% of current health expenditure in 2021. Overall, productivity losses were calculated at EUR 160.2 mil. The mean productivity losses were estimated to be 116 work days with 55.1 days lost due to premature retirement and absenteeism from work, 18.5 days lost due to mortality, and 42.4 days lost due to informal caregiving by family members. This study highlights the burden of stroke and underlines the need for stakeholders and policymakers to re-organize stroke care and promote interventions that have been proven cost-effective.