Gradual Certified Programming in Coq

Expressive static typing disciplines are a powerful way to achieve high-quality software. However, the adoption cost of such techniques should not be under-estimated. Just like gradual typing allows for a smooth transition from dynamically-typed to statically-typed programs, it seems desirable to support a gradual path to certified programming. We explore gradual certified programming in Coq, providing the possibility to postpone the proofs of selected properties, and to check "at runtime" whether the properties actually hold. Casts can be integrated with the implicit coercion mechanism of Coq to support implicit cast insertion a la gradual typing. Additionally, when extracting Coq functions to mainstream languages, our encoding of casts supports lifting assumed properties into runtime checks. Much to our surprise, it is not necessary to extend Coq in any way to support gradual certified programming. A simple mix of type classes and axioms makes it possible to bring gradual certified programming to Coq in a straightforward manner.Comment: DLS'15 final version, Proceedings of the ACM Dynamic Languages Symposium (DLS 2015

Trend in ice moistening the stratosphere – constraints from isotope data of water and methane

Water plays a major role in the chemistry and radiative budget of the stratosphere. Air enters the stratosphere predominantly in the tropics, where the very low temperatures around the tropopause constrain water vapour mixing ratios to a few parts per million. Observations of stratospheric water vapour show a large positive long-term trend, which can not be explained by change in tropopause temperatures. Trends in the partitioning between vapour and ice of water entering the stratosphere have been suggested to resolve this conundrum. We present measurements of stratospheric H_(2)O, HDO, CH_4 and CH_(3)D in the period 1991–2007 to evaluate this hypothesis. Because of fractionation processes during phase changes, the hydrogen isotopic composition of H_(2)O is a sensitive indicator of changes in the partitioning of vapour and ice. We find that the seasonal variations of H_(2)O are mirrored in the variation of the ratio of HDO to H_(2)O with a slope of the correlation consistent with water entering the stratosphere mainly as vapour. The variability in the fractionation over the entire observation period is well explained by variations in H_(2)O. The isotopic data allow concluding that the trend in ice arising from particulate water is no more than (0.01±0.13) ppmv/decade in the observation period. Our observations suggest that between 1991 and 2007 the contribution from changes in particulate water transported through the tropopause plays only a minor role in altering in the amount of water entering the stratosphere

Joachim Oelhaf and the first public autopsy in Gdansk in 1613

The first both in Gdansk and in Central Europe alleged public autopsy was performed by Joachim Oelhaf in February 1613. It was an evidence for Gdansk status as one of the leading anatomical centres in Europe. The aim of the article is to present the history of teaching medicine in Gdansk in early modern era and the eminent anatomists working in Academic Gymnasium of Gdansk. The preserved report of the autopsy of a new-born child with congenital defects is analysed as one of the very first texts in pathological anatomy. The described by Oelhaf case is identified as limb-body wall complex

ECG-gated multi-slice computed tomography in the detection of atrial septal aneurysms

An atrial septal aneurysm (ASA) is an uncommon cardiac abnormality. Clinical manifestation of this abnormality remains unclear: some authors have suggested an association between ASA and arrhythmias or between ASA and cerebral ischaemia. A major role in the diagnosis of ASA to date has been played by transoesophageal echocardiography and transthoracic echocardiography. The purpose of this paper is to present the role of multi-slice computed tomography with ECG gating in the detection and analysis of ASA. (Folia Morphol 2008; 67: 126–128

Digital Dilemma 2018

In October 2018 a one-day conference was held at the UCL Institute of Archaeology focussing on the ‘Digital Dilemma’ in biological archaeology —specifically human remains research where the use of digitisation methods have increased exponentially over the last decade while comparatively little discussion of the ethical and legal considerations of these data has taken place. Papers presented at Digital Dilemma 2018 explored the use of digital data in human remains research, discussing both the benefits provided by these data, areas of ethical or methodological concern and suggestions for future research. This paper and the following conference proceedings will discuss this research demonstrating the importance that this Digital Dilemma in archaeology continues to be discussed and considered in future research

Coronary artery fistulas morphology in coronary computed tomography angiography

Background: The aim of the study was to evaluate coronary artery fistulas (CAFs) in coronary computed tomography angiography (coronary CTA) and verify whether there is correlation between the fistula’s morphology and other cardiac functional findings and clinical data.Materials and methods: A group of 14,308 patients who were diagnosed in coronary CTA was retrospectively analysed. Achieved data were related to referrals.Results: Coronary artery fistula frequency was 0.43% in the examined population. The assessment of coronary artery disease was the most frequent indication for the examination. In 2 out of 3 cases the diagnosis of CAFs was incidental. Fistulas to cardiac chambers were significantly shorter than those to other vascular structures (19.9 vs. 61.8 mm, respectively, p = 0.001). Pulmonary trunk was most often the drainage site. Fistulas with singular supply and drainage constituted the majority. The new morphologic classification of CAFs was introduced with linear, spiral, aneurysmal, grid-like and mixed types. Most numerous was the spiral type group. Patients with aneurysmal fistulas had a tendency for wider diameter of aorta and pulmonary trunk. Smallest left ventricle fraction was observed in gridlike fistulas (48.0%, comparing to 59.2% for all patients with fistulas, p = 0.001). Concomitant abnormalities were found in 13.1% of CAFs patients.Conclusions: Computed tomography angiography has proven to be a useful tool in CAFs detection and morphological assessment. Proposed classification may simplify the predictions whether fistula has a significant influence on cardiac function; however, further studies are needed