Homopiperazine-1,4-diium bis­[hexa­aqua­cobalt(II)] tris­ulfate

In the title compound, (C5H14N2)[Co(H2O)6]2(SO4)3, the cationic framework is built up of mixed organic–inorganic fragments, namely [Co(H2O)6]2+ and [C5H14N2]2+. The [Co(H2O)6]2+ cations form unconnected octa­hedra. Sulfate anions inter­calated between cationic species connect them via N—H⋯O and O—H⋯O hydrogen bonds and electrostatic inter­actions

4-Chloro­anilinium hydrogen oxalate hemihydrate

In the title hydrated mol­ecular salt, C6H7ClN+·C2HO4 −·0.5H2O, the water O atom lies on a crystallographic twofold axis. In the crystal, the anions are linked by O—H⋯O hydrogen bonds, forming chains propagating along the b axis. These chains are inter­connected through O—H⋯O hydrogen bonds from the water mol­ecules and N—H⋯O hydrogen bonds from the cations, building layers parallel to the ab plane

(4-Chloro­phen­yl)methanaminium chloride hemihydrate

In the title hydrated salt, C7H9ClN+·Cl−·0.5H2O, the water O atom lies on a crystallographic twofold axis. In the crystal, the monoprotonated 4-chloro­benzyl­ammonium cation forms N—H⋯Cl and N—H⋯O hydrogen bonds and the water mol­ecule forms O—H⋯Cl hydrogen bonds, generating layers lying parallel to the bc plane

2,6-Diethyl­anilinium perchlorate

The asymmetric unit of the title mol­ecular salt, C10H16N+·ClO4 −, contains two cations and two anions. The atoms of one of the ethyl side chains of one of the cations are disordered over two sets of sites in a 0.531 (13):0.469 (13) ratio. In the crystal, the components are linked by N—H⋯O and bifurcated N—H⋯(O,O) hydrogen bonds and weaker C—H⋯O inter­actions, such that the organic cations alternate with the perchlorate anions, forming ribbons in the a-axis direction

4-Meth­oxy­anilinium nitrate

The title compound, C7H10NO+·NO3 −, crystallized with two p-ansidinium cations and two nitrate anions in the asymmetric unit. As well as Columbic and van der Waals forces, moleucles inter­act via multiple bifurcated N—H⋯O hydrogen bonds that help consolidate the crystal packing, resulting in a three-dimensional network

Fragmentation of exotic oxygen isotopes

Abrasion-ablation models and the empirical EPAX parametrization of projectile fragmentation are described. Their cross section predictions are compared to recent data of the fragmentation of secondary beams of neutron-rich, unstable 19,20,21O isotopes at beam energies near 600 MeV/nucleon as well as data for stable 17,18O beams

Bis(2,3-dimethyl­anilinium) tetra­chlorido­zincate dihydrate

In the title compound, (C8H12N)2[ZnCl4]·2H2O, the Zn atom is coordinated by four Cl atoms in a tetra­hedral geometry. The water mol­ecules and the organic cations inter­act with the [ZnCl4]2− complex anions, building up a two-dimensional hydrogen-bonded network parallel to (100)

Detecting referral and selection bias by the anonymous linkage of practice, hospital and clinic data using Secure and Private Record Linkage (SAPREL): case study from the evaluation of the Improved Access to Psychological Therapy (IAPT) service

Background: The evaluation of demonstration sites set up to provide improved access to psychological therapies (IAPT) comprised the study of all people identified as having common mental health problems (CMHP), those referred to the IAPT service, and a sample of attenders studied in-depth. Information technology makes it feasible to link practice, hospital and IAPT clinic data to evaluate the representativeness of these samples. However, researchers do not have permission to browse and link these data without the patients’ consent. Objective: To demonstrate the use of a mixed deterministic-probabilistic method of secure and private record linkage (SAPREL) - to describe selection bias in subjects chosen for in-depth evaluation. Method: We extracted, pseudonymised and used fuzzy logic to link multiple health records without the researcher knowing the patient’s identity. The method can be characterised as a three party protocol mainly using deterministic algorithms with dynamic linking strategies; though incorporating some elements of probabilistic linkage. Within the data providers’ safe haven we extracted: Demographic data, hospital utilisation and IAPT clinic data; converted post code to index of multiple deprivation (IMD); and identified people with CMHP. We contrasted the age, gender, ethnicity and IMD for the in-depth evaluation sample with people referred to IAPT, use hospital services, and the population as a whole. Results: The in IAPT-in-depth group had a mean age of 43.1 years; CI: 41.0 - 45.2 (n = 166); the IAPT-referred 40.2 years; CI: 39.4 - 40.9 (n = 1118); and those with CMHP 43.6 years SEM 0.15. (n = 12210). Whilst around 67% of those with a CMHP were women, compared to 70% of those referred to IAPT, and 75% of those subject to indepth evaluation (Chi square p< 0.001). The mean IMD score for the in-depth evaluation group was 36.6; CI: 34.2 - 38.9; (n = 166); of those referred to IAPT 38.7; CI: 37.9 - 39.6; (n = 1117); and of people with CMHP 37.6; CI 37.3- 37.9; (n = 12143). Conclusions: The sample studied in-depth were older, more likely female, and less deprived than people with CMHP, and fewer had recorded ethnic minority status. Anonymous linkage using SAPREL provides insight into the representativeness of a study population and possible adjustment for selection bias

Mechanisms of plastic instability and fracture of compressed and tensile tested Mg-Li alloys investigated using the acoustic emission method

The results of the investigation of both mechanical and acoustic emission (AE) behaviors of Mg4Li5Al alloy subjected to compression and tensile tests at room temperature are compared with the test results obtained using the same alloy and loading scheme but at elevated temperatures. The main aim of the paper is to investigate, to determine and to explain the possible influence of factors related with enhanced internal stresses such as: segregation of precipitates along grain boundaries or solute atoms along dislocations (Cottrell atmospheres) or dislocation pile-ups at grain boundaries which create very high stress concentration leading to fracture. The results show that the plastic instabilities are related to the Portevin–Le Châtelier phenomenon (PL effect) and they are correlated with the generation of AE peaks. The fractography of breaking samples was analyzed on the basis of light (optical), TEM and SEM images

Estimating parameters for probabilistic linkage of privacy-preserved datasets.

Background: Probabilistic record linkage is a process used to bring together person-based records from within the same dataset (de-duplication) or from disparate datasets using pairwise comparisons and matching probabilities. The linkage strategy and associated match probabilities are often estimated through investigations into data quality and manual inspection. However, as privacy-preserved datasets comprise encrypted data, such methods are not possible. In this paper, we present a method for estimating the probabilities and threshold values for probabilistic privacy-preserved record linkage using Bloom filters. Methods: Our method was tested through a simulation study using synthetic data, followed by an application using real-world administrative data. Synthetic datasets were generated with error rates from zero to 20% error. Our method was used to estimate parameters (probabilities and thresholds) for de-duplication linkages. Linkage quality was determined by F-measure. Each dataset was privacy-preserved using separate Bloom filters for each field. Match probabilities were estimated using the expectation-maximisation (EM) algorithm on the privacy-preserved data. Threshold cut-off values were determined by an extension to the EM algorithm allowing linkage quality to be estimated for each possible threshold. De-duplication linkages of each privacy-preserved dataset were performed using both estimated and calculated probabilities. Linkage quality using the F-measure at the estimated threshold values was also compared to the highest F-measure. Three large administrative datasets were used to demonstrate the applicability of the probability and threshold estimation technique on real-world data. Results: Linkage of the synthetic datasets using the estimated probabilities produced an F-measure that was comparable to the F-measure using calculated probabilities, even with up to 20% error. Linkage of the administrative datasets using estimated probabilities produced an F-measure that was higher than the F-measure using calculated probabilities. Further, the threshold estimation yielded results for F-measure that were only slightly below the highest possible for those probabilities. Conclusions: The method appears highly accurate across a spectrum of datasets with varying degrees of error. As there are few alternatives for parameter estimation, the approach is a major step towards providing a complete operational approach for probabilistic linkage of privacy-preserved datasets