Learning to Noise: Application-Agnostic Data Sharing with Local Differential Privacy

The collection and sharing of individuals' data has become commonplace in many industries. Local differential privacy (LDP) is a rigorous approach to preserving data privacy even from a database administrator, unlike the more standard central differential privacy. To achieve LDP, one traditionally adds noise directly to each data dimension, but for high-dimensional data the level of noise required for sufficient anonymization all but entirely destroys the data's utility. In this paper, we introduce a novel LDP mechanism that leverages representation learning to overcome the prohibitive noise requirements of direct methods. We demonstrate that, rather than simply estimating aggregate statistics of the privatized data as is the norm in LDP applications, our method enables the training of performant machine learning models. Unique applications of our approach include private novel-class classification and the augmentation of clean datasets with additional privatized features. Methods that rely on central differential privacy are not applicable to such tasks. Our approach achieves significant performance gains on these tasks relative to state-of-the-art LDP benchmarks that noise data directly

`Representing and Being Represented in Turn’ - A Symposium on Hélène Landemore’s "Open Democracy"

Hélene Landemore’s Open Democracy challenges today’s democracies to meet their legitimacy deficits by opening up a wide array of participatory opportunities, from enhanced forms of direct democracy, to internet crowdsourcing, to representation through random selection to a citizens’ assembly: “representing and being represented in turn” (p. xvii).  Her aim: to replace citizen consent with citizen power.  The critics advance both praise and misgivings.  Joshua Cohen asks if Landemore's innovations are best understood as supplements or alternatives to the current system. Daniele Cammack argues for the significance of open mass meetings as well as smaller representative bodies. Peter Stone considers citizens’ assemblies inadequate for popular sovereignty.  Christopher Achen warns of problems in accurate representation, through both self-selection into the lottery and domination in the discussion. Ethan Lieb argues that particular innovations are useful only in some contexts, and that in each citizens should learn their appropriate role responsibilities. Landemore responds by agreeing, clarifying and rebutting

Investigating behavioural and computational approaches for defining imprecise regions

People often communicate with reference to informally agreedplaces, such as “the city centre”. However, views of the spatial extent of such areas may vary, resulting in imprecise regions. We compare perceptions of Sheffield’s City Centre from a street survey to extents derived from various web-based sources. Such automated approaches have advantages of speed, cost and repeatability. We show that footprints from web sources are often in concordance with models derived from more labour-intensive methods. Notable exceptions however were found with sources advertising or selling residential property. Agreement between sources was measured by aggregating them to identify locations of consensus

Disagreement and Consensus: The Need for Dynamic Updating in Public Deliberation

This analysis compares a consensus-oriented procedure, Princeton Future, with a more adversarial procedure, the public meetings of the Princeton, N.J. borough council, organized as public hearings. It finds that the consensus-oriented procedure failed to pick up significant conflicting interests among the citizens and as a consequence failed to provide venues for discussing and possibly negotiating those interests. It advises that deliberative democratic procedures provide for dynamic updating on the underlying and changing interest structure before and during deliberation, with particular attention to the important lines of conflict. Thus facilitators should help participants in deliberation not only forge common interests but also clarify their conflicting interests

Two cases of listeria rhombencephalitis

Listeria rhombencephalitis (LRE) is a rare encephalitis of the hindbrain that can present with a variety of neurological symptoms. It is a diagnostic challenge, but prompt antimicrobial therapy is important to prevent high rates of mortality and morbidity. We report two cases of LRE, with several contrasting clinical features and different disease courses. Despite being rare, it is important to consider listeria in patients with possible meningoencephalitis, even if cultures are negative. Empirical treatment of meningoencephalitis should provide coverage for listeria, especially if the patient is at risk of listeriosis or there is a potential history of listeria exposure.</p

Combined RT-PCR and host response point-of-care testing in patients hospitalised with suspected COVID-19: a prospective diagnostic accuracy study

Introduction: RT-PCR has suboptimal sensitivity for the diagnosis of COVID-19. A composite reference standard comprising RT-PCR plus radiological and clinical features has been recommended for diagnostic accuracy studies. The FebriDx finger prick point-of-care test detects an antiviral host response protein (MxA) in 10 min. We evaluated the diagnostic accuracy of FebriDx and RT-PCR compared to a composite reference standard.Methods: adults presenting to hospital with suspected COVID-19 were tested by FebriDx and RT-PCR. A composite reference standard was used to classify patients as having COVID-19 based on RT-PCR positivity, or RT-PCR negativity with COVID-19 radiological findings or other clinical criteria. Measures of accuracy were calculated for MxA alone, RT-PCR alone, and both combined. This study is registered with the ISRCTN (ISRCTN14966673) and has completed.Results: a total of 478 patients were tested, with valid results in 475. Of these 475 patients, 222 (46.7%) were classified as having COVID-19; 192 (40.4%) were RT-PCR positive, and 30 (6.3%) were RT-PCR negative and diagnosed on radiological/clinical criteria. Sensitivity of FebriDx MxA vs the composite reference standard was 186/222 (83.8%, 95% CI 78.3–88.4) and was similar to the sensitivity of RT-PCR (192/222 (86.5%, 95% CI 81.3–90.7), (difference of 2.7%, 95% CI − 3.9 to 9.3, p = 0.42). The sensitivity of combined FebriDx and RT-PCR was 208/222 (93.7%) which was superior to both RT-PCR alone (difference of 9.9, 95% CI 4.1–15.9; p = 0.001) and FebriDx MxA alone (difference of 7.2, 95% CI 1.6–12.9; p = 0.011).Conclusion: sensitivity of combined FebriDx and RT-PCR testing was superior to each alone for the detection of COVID-19 in hospital and may improve infection control and treatment decisions

FebriDx host response point-of-care testing improves patient triage for coronavirus disease 2019 (COVID-19) in the emergency department

OBJECTIVES: Patients presenting to hospital with suspected coronavirus disease 2019 (COVID-19), based on clinical symptoms, are routinely placed in a cohort together until polymerase chain reaction (PCR) test results are available. This procedure leads to delays in transfers to definitive areas and high nosocomial transmission rates. FebriDx is a finger-prick point-of-care test (PoCT) that detects an antiviral host response and has a high negative predictive value for COVID-19. We sought to determine the clinical impact of using FebriDx for COVID-19 triage in the emergency department (ED).DESIGN: We undertook a retrospective observational study evaluating the real-world clinical impact of FebriDx as part of an ED COVID-19 triage algorithm.SETTING: Emergency department of a university teaching hospital.PATIENTS: Patients presenting with symptoms suggestive of COVID-19, placed in a cohort in a 'high-risk' area, were tested using FebriDx. Patients without a detectable antiviral host response were then moved to a lower-risk area.RESULTS: Between September 22, 2020, and January 7, 2021, 1,321 patients were tested using FebriDx, and 1,104 (84%) did not have a detectable antiviral host response. Among 1,104 patients, 865 (78%) were moved to a lower-risk area within the ED. The median times spent in a high-risk area were 52 minutes (interquartile range [IQR], 34-92) for FebriDx-negative patients and 203 minutes (IQR, 142-255) for FebriDx-positive patients (difference of -134 minutes; 95% CI, -144 to -122; P &lt; .0001). The negative predictive value of FebriDx for the identification of COVID-19 was 96% (661 of 690; 95% CI, 94%-97%).CONCLUSIONS: FebriDx improved the triage of patients with suspected COVID-19 and reduced the time that severe acute respiratory coronavirus virus 2 (SARS-CoV-2) PCR-negative patients spent in a high-risk area alongside SARS-CoV-2-positive patients.</p

Diagnostic accuracy of the FebriDx host response point-of-care test in patients hospitalised with suspected COVID-19

IntroductionManagement of the COVID-19 pandemic is hampered by long delays associated with centralised laboratory PCR testing. In hospitals this leads to poor patient flow and nosocomial transmission and so rapid, accurate diagnostic tests are urgently required. The FebriDx is a point-of-care test that detects an antiviral host response protein in finger prick blood within 10 min, but its accuracy for the identification of COVID-19 is unknown.MethodsWe performed a real-world diagnostic accuracy study of FebriDx in hospitalised patients during the first wave of the pandemic. Measures of diagnostic accuracy were calculated based on FebriDx results compared to the reference standard of SARS-CoV-2 PCR on combined nose and throat swabs. A multivariable predictive model including FebriDx, age, sex, and clinical characteristics was developed and underwent internal validation.ResultsFebriDx was performed on 251 patients and gave a valid result in 248. 118 of 248 (48%) were PCR positive for COVID-19. FebriDx results were available after 10 min compared with 1.7 (1.6 to 2.1) hours with point-of-care PCR testing and 23.4 (17.2 to 31.1) hours with laboratory PCR testing. Sensitivity of FebriDx for the identification of COVID-19 was 93% (110/118; 95% CI 87 to 97%) and specificity was 86% (112/130; 95%CI 79 to 92%). Positive and negative likelihood ratios were 6.73 (95%CI 4.37 to 10.37) and 0.08 (95%CI 0.04 to 0.15) respectively. In the multivariate model age, sex and other clinical features did not contribute significantly to the effect of the FebriDx result in distinguishing patients with and without COVID-19.ConclusionsDuring the first wave of the pandemic, FebriDx had high accuracy for the identification of COVID-19 in hospitalised adults and could be deployed as a front door triage tool

A phase 2 open-label study of carboplatin in combination with gemcitabine as a dose-dense schedule in patients with locally advanced or metastatic breast cancer that are resistant to anthracyclines and taxanes

Background: Anthracycline- and taxane-based regimens form the mainstay of chemotherapy treatment in metastatic breast cancer. In patients who develop resistance to these agents, management options are limited and there is no standard of care. Thus, investigation into other chemotherapeutic agents is warranted.Methods: In this non-randomised prospective trial, patients with human epidermal growth factor 2 (HER-2)-negative locally advanced or metastatic breast cancer that were anthracycline- and taxane-resistant were treated with carboplatin at a dose equivalent to an area under the concentration–time curve of 4.5 mg/ml.min on day 1 and gemcitabine 1500 mg/m2 on day 2 of every 2-week cycle. The primary end point was overall response rate.Results: A total of five patients were enrolled prior to early termination due to difficulty in recruitment. The principal reason for recruitment difficulty was mandating anthracycline and taxane pre-treatment and HER-2 negativity. One patient had a complete response, one had a partial response, one had stable disease and two had progressive disease. Grade 4 neutropenia occurred in two patients.Conclusions: In this patient population, inclusion criteria that are too stringent may result in difficulties reaching recruitment targets. Carboplatin in combination with gemcitabine appears to be a safe option for treatment of patients with locally advanced or metastatic breast cancer. Due to the small sample size, it is not possible to draw firm conclusions regarding efficacy from this trial.Registration: EU Clinical Trials Register ID 2005-005164-83, registered on 10 April 200