Astrobiological Complexity with Probabilistic Cellular Automata

Search for extraterrestrial life and intelligence constitutes one of the major endeavors in science, but has yet been quantitatively modeled only rarely and in a cursory and superficial fashion. We argue that probabilistic cellular automata (PCA) represent the best quantitative framework for modeling astrobiological history of the Milky Way and its Galactic Habitable Zone. The relevant astrobiological parameters are to be modeled as the elements of the input probability matrix for the PCA kernel. With the underlying simplicity of the cellular automata constructs, this approach enables a quick analysis of large and ambiguous input parameters' space. We perform a simple clustering analysis of typical astrobiological histories and discuss the relevant boundary conditions of practical importance for planning and guiding actual empirical astrobiological and SETI projects. In addition to showing how the present framework is adaptable to more complex situations and updated observational databases from current and near-future space missions, we demonstrate how numerical results could offer a cautious rationale for continuation of practical SETI searches.Comment: 37 pages, 11 figures, 2 tables; added journal reference belo

WATER SORPTION AND SOLUBILITY OF DIFFERENT CALCIUM HYDROXIDE CEMENTS

Objectives: Calcium hydroxide cements have been largely used in deep cavities due to their abilities to stimulate dentin formation. However, their resistance can be relatively low and their solubility relatively high, in many instances. This study evaluated water sorption and solubility of different calcium hydroxide cements, in order to show alterations that may reduce their effectiveness. Material and methods: Five discs (20 mm in diameter and 1.5 mm thick) of three different materials (Biocal (R), Dycal (R) and Hidro C (R)) were prepared with the aid of a ring-shaped metallic matrix. After being stored at 37 C for 24 h, the discs were weighed on a precision weight scale, dehydrated and weighed again. Immediately after weighing, discs were stored for a week in 50 mL of distilled water at 37 degrees C and, then, weighed again, dehydrated and submitted to a new weighing. The loss of soluble material and its water sorption was obtained from the difference between the initial and the final dry mass of each disc, after 1 week of immersion in water. Data were analyzed for significant differences by two-way ANOVA and Tukey's test (p<0.05). Results: Mean water sorption values (g) +/- standard deviation and percentage (%), for each evaluated cement, were: Biocal (R) (0.006 +/- 0.001 / 2.15); Dycal (R) (0.016 +/- 0.004 / 5.49); and Hidro C (R) (0.025 +/- 0.003 / 8.27). Mean solubility values (g) +/- standard deviation and percentage (%), for each evaluated cement, were: Biocal (R) (0.002 +/- 0.001 / 0.72); Dycal (R) (0.013 +/- 0.004 / 4.21); and Hidro C (R) (0.023 +/- 0.004 / 7.65). Conclusions: Biocal (R) absorbed less water and was less soluble than the other evaluated cements; Hidro C (R) exhibited the highest water sorption and solubility values; and there were significant differences among all evaluated experimental groups.175427431SESu/MEC (PET-Brazil

Neuroimaging and clinical outcomes of oral anticoagulant associated ICH

OBJECTIVE: Whether intracerebral haemorrhage (ICH) associated with non-vitamin K antagonist oral anticoagulants (NOAC-ICH) has a better outcome compared to ICH associated with vitamin-K antagonists (VKA-ICH) is uncertain. METHODS: We performed a systematic review and individual patient data meta-analysis of cohort studies comparing clinical and radiological outcomes between NOAC-ICH and VKA-ICH patients. The primary outcome measure was 30-day all-cause mortality. All outcomes were assessed in multivariable regression analyses adjusted for age, sex, ICH location and intraventricular haemorrhage extension. RESULTS: We included 7 eligible studies comprising 219 NOAC-ICH and 831 VKA-ICH patients (mean age:77 years,52.5% females). The 30-day mortality was similar between NOAC-ICH and VKA-ICH (24.3% vs. 26.5%; HR=0.94, 95%CI: 0.67 to 1.31). However, in multivariable analyses adjusting for potential confounders, NOAC-ICH was associated with: lower admission National Institutes of Health Stroke Scale (NIHSS) score (linear regression coefficient=-2.83, 95%CI:-5.28 to -0.38); lower likelihood of severe stroke (NIHSS>10 points) on admission (OR=0.50, 95%CI: 0.30 to 0.84); and smaller baseline haematoma volume (linear regression coefficient=-0.24,95%CI:-0.47 to -0.16). The two groups did not differ in the likelihood of: baseline haematoma volume less than 30cm3 (OR=1.14, 95%CI: 0.81 to 1.62); haematoma expansion (OR=0.97, 95%CI: 0.63 to 1.48); in-hospital mortality (OR=0.73,95%CI: 0.49 to 1.11); functional status at discharge (common OR=0.78, 95%CI: 0.57 to 1.07); or functional status at three months (common OR=1.03, 95%CI: 0.75 to 1.43). INTERPRETATION: Although functional outcome at discharge, one month or three months were comparable after NOAC-ICH and VKA-ICH, patients with NOAC-ICH had smaller baseline haematoma volumes and less severe acute stroke syndromes. This article is protected by copyright. All rights reserved