430 research outputs found
Designing a privacy-preserving protocol to support transient and purpose-specific data linkages
ABSTRACT
Objectives
To describe the design of a privacy-preserving protocol to support transient and purpose-specific data linkages between defined organisations in the health domain, to discuss how the specific technical and governance constraints of each organisation shaped the design of the protocol, and to propose approaches to reduce the costs associated with the use of privacy-preserving protocols for such linkages.
Approach
Privacy-preserving protocols enable individual-level data to be linked across organisations without any requirement for direct identifiers to be released outside of organisational boundaries. Such protocols can reduce the risk that data released by organisations can be associated with an identifiable subject. Use of these protocols in practical scenarios requires that their computational and communication steps are mutually acceptable to each participating organisation from a technical and governance perspective. For transient and purpose-specific linkages, organisations may have no previous experience of participation in a privacy-preserving protocol and therefore no established set of mutually acceptable steps. We describe the design of a privacy-preserving protocol for a national health research project - in which specific health data from local and national organisations is to be linked to construct longitudinal patient records for analysis - and discuss how the design of the protocol was shaped by the specific technical and governance constraints of each organisation.
Results
Organisations are subject to varied technical constraints, such as expertise and infrastructure, and varied governance constraints, such as policies and procedures. Therefore, different computational and communication steps may be acceptable to different organisations. Design of a privacy-preserving protocol requires interaction with each organisation to determine their specific constraints and to understand the space of mutually acceptable steps from which a protocol can be composed. Initial costs for the design of a privacy-preserving protocol can therefore be significant. However, once mutually acceptable steps have been established between certain organisations, ongoing costs for subsequent linkages should be reduced. To reduce both initial and ongoing costs, different approaches can used to support coordination of organisations on technical and governance matters. Such approaches could include: (i) education and training, (ii) tooling and accreditation, and (iii) published best practice.
Conclusion
Use of privacy-preserving protocols for transient and purpose-specific data linkages requires coordination between organisations, which can be initially costly to establish. Reduction in initial and ongoing costs can be achieved through approaches that support both initial and ongoing coordination
Visual art inspired by the collective feeding behavior of sand-bubbler crabs
Sand--bubblers are crabs of the genera Dotilla and Scopimera which are known
to produce remarkable patterns and structures at tropical beaches. From these
pattern-making abilities, we may draw inspiration for digital visual art. A
simple mathematical model is proposed and an algorithm is designed that may
create such sand-bubbler patterns artificially. In addition, design parameters
to modify the patterns are identified and analyzed by computational aesthetic
measures. Finally, an extension of the algorithm is discussed that may enable
controlling and guiding generative evolution of the art-making process
Two-electron spin correlations in precision placed donors in silicon
Substitutional donor atoms in silicon are promising qubits for quantum computation with extremely long relaxation and dephasing times demonstrated. One of the critical challenges of scaling these systems is determining inter-donor distances to achieve controllable wavefunction overlap while at the same time performing high fidelity spin readout on each qubit. Here we achieve such a device by means of scanning tunnelling microscopy lithography. We measure anti-correlated spin states between two donor-based spin qubits in silicon separated by 16 ± 1 nm. By utilising an asymmetric system with two phosphorus donors at one qubit site and one on the other (2P−1P), we demonstrate that the exchange interaction can be turned on and off via electrical control of two in-plane phosphorus doped detuning gates. We determine the tunnel coupling between the 2P−1P system to be 200 MHz and provide a roadmap for the observation of two-electron coherent exchange oscillations
Calibration of myocardial T2 and T1 against iron concentration.
BACKGROUND: The assessment of myocardial iron using T2* cardiovascular magnetic resonance (CMR) has been validated and calibrated, and is in clinical use. However, there is very limited data assessing the relaxation parameters T1 and T2 for measurement of human myocardial iron.
METHODS: Twelve hearts were examined from transfusion-dependent patients: 11 with end-stage heart failure, either following death (n=7) or cardiac transplantation (n=4), and 1 heart from a patient who died from a stroke with no cardiac iron loading. Ex-vivo R1 and R2 measurements (R1=1/T1 and R2=1/T2) at 1.5 Tesla were compared with myocardial iron concentration measured using inductively coupled plasma atomic emission spectroscopy.
RESULTS: From a single myocardial slice in formalin which was repeatedly examined, a modest decrease in T2 was observed with time, from mean (± SD) 23.7 ± 0.93 ms at baseline (13 days after death and formalin fixation) to 18.5 ± 1.41 ms at day 566 (p<0.001). Raw T2 values were therefore adjusted to correct for this fall over time. Myocardial R2 was correlated with iron concentration [Fe] (R2 0.566, p<0.001), but the correlation was stronger between LnR2 and Ln[Fe] (R2 0.790, p<0.001). The relation was [Fe] = 5081•(T2)-2.22 between T2 (ms) and myocardial iron (mg/g dry weight). Analysis of T1 proved challenging with a dichotomous distribution of T1, with very short T1 (mean 72.3 ± 25.8 ms) that was independent of iron concentration in all hearts stored in formalin for greater than 12 months. In the remaining hearts stored for <10 weeks prior to scanning, LnR1 and iron concentration were correlated but with marked scatter (R2 0.517, p<0.001). A linear relationship was present between T1 and T2 in the hearts stored for a short period (R2 0.657, p<0.001).
CONCLUSION: Myocardial T2 correlates well with myocardial iron concentration, which raises the possibility that T2 may provide additive information to T2* for patients with myocardial siderosis. However, ex-vivo T1 measurements are less reliable due to the severe chemical effects of formalin on T1 shortening, and therefore T1 calibration may only be practical from in-vivo human studies
From working collections to the World Germplasm Project: agricultural modernization and genetic conservation at the Rockefeller Foundation
This paper charts the history of the Rockefeller Foundation’s participation in the collection and long-term preservation of genetic diversity in crop plants from the 1940s through the 1970s. In the decades following the launch of its agricultural program in Mexico in 1943, the Rockefeller Foundation figured prominently in the creation of world collections of key economic crops. Through the efforts of its administrators and staff, the foundation subsequently parlayed this experience into a leadership role in international efforts to conserve so-called plant genetic resources. Previous accounts of the Rockefeller Foundation’s interventions in international agricultural development have focused on the outcomes prioritized by foundation staff and administrators as they launched assistance programs and especially their characterization of the peoples and ‘‘problems’’ they encountered abroad. This paper highlights instead how foundation administrators and staff responded to a newly emergent international agricultural concern—the loss of crop genetic diversity. Charting the foundation’s responses to this concern, which developed only after agricultural modernization had begun and was understood to be produced by the successes of the foundation’s own agricultural assistance programs, allows for greater interrogation of how the foundation understood and projected its central position in international agricultural research activities by the 1970s.Research for this article was supported in part by a grant-in-aid from the Rockefeller Archive Center
Labour migration, communities and perceptions of social cohesion in England
Abstract
The unexpected scale of labour migration from eastern Europe to the UK following EU enlargement in 2004 was thought
to pose a threat to the cohesiveness of those local communities hosting larger influxes of migrants. Nevertheless,
areas rich in community capacity may have been able to incorporate migrant workers in ways that sustained social
cohesion. This paper explores the effects of labour migration on residents’ perceptions of social cohesion in urban
areas in England using multivariate statistical techniques. The statistical results suggest that post-enlargement migration
weakened social cohesion, but that the prospects of social incorporation were better in areas with stronger community
capacity. Theoretical and practical implications of the findings are discussed
Rectification of the Water Permeability in COS-7 Cells at 22, 10 and 0°C
The osmotic and permeability parameters of a cell membrane are essential physico-chemical properties of a cell and particularly important with respect to cell volume changes and the regulation thereof. Here, we report the hydraulic conductivity, Lp, the non-osmotic volume, Vb, and the Arrhenius activation energy, Ea, of mammalian COS-7 cells. The ratio of Vb to the isotonic cell volume, Vc iso, was 0.29. Ea, the activation energy required for the permeation of water through the cell membrane, was 10,700, and 12,000 cal/mol under hyper- and hypotonic conditions, respectively. Average values for Lp were calculated from swell/shrink curves by using an integrated equation for Lp. The curves represented the volume changes of 358 individually measured cells, placed into solutions of nonpermeating solutes of 157 or 602 mOsm/kg (at 0, 10 or 22°C) and imaged over time. Lp estimates for all six combinations of osmolality and temperature were calculated, resulting in values of 0.11, 0.21, and 0.10 µm/min/atm for exosmotic flow and 0.79, 1.73 and 1.87 µm/min/atm for endosmotic flow (at 0, 10 and 22°C, respectively). The unexpected finding of several fold higher Lp values for endosmotic flow indicates highly asymmetric membrane permeability for water in COS-7. This phenomenon is known as rectification and has mainly been reported for plant cell, but only rarely for animal cells. Although the mechanism underlying the strong rectification found in COS-7 cells is yet unknown, it is a phenomenon of biological interest and has important practical consequences, for instance, in the development of optimal cryopreservation
Positioning discourse on homophobia in schools: what have lesbian and gay families got to say?
This paper reports findings from a study in England, which investigated the experiences of lesbian and gay parents in relation to homophobia in primary and secondary schools. The study was part of a larger European Union project investigating the impact of family and school alliances against homophobic and transphobic bullying in schools across six nation states. Qualitative in-depth semi-structured interviews with seven lesbian and gay parents from five families were conducted to explore their unique experience and perspectives on these issues. Discourse analysis was used to facilitate understanding of how lesbian and gay families negotiated the outsider/insider and public/private spheres of the school and communities of which they were a part. Parents identified a number of strategies to address their experiences of homophobia within schools. The findings have implications for how social work recognises and promotes diversity and equality when working with lesbian, gay, bisexual and transgender families, as social workers have a powerful role in supporting families. This involves recognising the strengths of lesbian, gay, bisexual and transgender families in their assessments
Positioning discourse on homophobia in schools: What have lesbian and gay families got to say?
This paper reports findings from a study in England, which investigated the experiences of lesbian and gay parents in relation to homophobia in primary and secondary schools. The study was part of a larger European Union project investigating the impact of family and school alliances against homophobic and transphobic bullying in schools across six nation states. Qualitative in-depth semi-structured interviews with seven lesbian and gay parents from five families were conducted to explore their unique experience and perspectives on these issues. Discourse analysis was used to facilitate understanding of how lesbian and gay families negotiated the outsider/insider and public/private spheres of the school and communities of which they were a part. Parents identified a number of strategies to address their experiences of homophobia within schools. The findings have implications for how social work recognises and promotes diversity and equality when working with lesbian, gay, bisexual and transgender families, as social workers have a powerful role in supporting families. This involves recognising the strengths of lesbian, gay, bisexual and transgender families in their assessments
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