Stress on the Ward – An Empirical Study of the Nonlinear Relationship between Organizational Workload and Service Quality

We discuss the impact of organizational workload on professional service outcomes, such as survival rates in hospitals. The prevailing view in the literature is that service quality deteriorates when organizational workload increases. In contrast, we argue that the relationship between workload and service outcomes is nonlinear and that there is a quality-optimal workload level. Whilst outcomes deteriorate with increasing workload when workload levels are already high, they will improve if workload increases from a low level. We reach this hypothesis by combining three perspectives: (i) the queuing theory perspective, with its focus on congestion, (ii) a discretionary choice perspective, with a focus on decisions made by professionals in response to changes in workload, and (iii) an endocrinological perspective, with a focus on the subconscious eff ects of workload on worker performance through the cognitive impact of stress hormones. Using a patient census of 1.4 million patients in 624 departments across 101 hospitals, we provide empirical support for the nonlinearity hypothesis in the context of hospital survival rates. We further discuss the implications for hospital capacity planning and the wider implications for service operations management.Service quality; service outcomes; organizational workload; hospital capacity planning; behavioral operations; stress

An interior-point method for mpecs based on strictly feasible relaxations.

An interior-point method for solving mathematical programs with equilibrium constraints (MPECs) is proposed. At each iteration of the algorithm, a single primaldual step is computed from each subproblem of a sequence. Each subproblem is defined as a relaxation of the MPEC with a nonempty strictly feasible region. In contrast to previous approaches, the proposed relaxation scheme preserves the nonempty strict feasibility of each subproblem even in the limit. Local and superlinear convergence of the algorithm is proved even with a less restrictive strict complementarity condition than the standard one. Moreover, mechanisms for inducing global convergence in practice are proposed. Numerical results on the MacMPEC test problem set demonstrate the fast-local convergence properties of the algorithm

AN INTERIOR-POINT METHOD FOR MPECs BASED ON STRICTLY FEASIBLE RELAXATIONS.

An interior-point method for solving mathematical programs with equilibrium constraints (MPECs) is proposed. At each iteration of the algorithm, a single primaldual step is computed from each subproblem of a sequence. Each subproblem is defined as a relaxation of the MPEC with a nonempty strictly feasible region. In contrast to previous approaches, the proposed relaxation scheme preserves the nonempty strict feasibility of each subproblem even in the limit. Local and superlinear convergence of the algorithm is proved even with a less restrictive strict complementarity condition than the standard one. Moreover, mechanisms for inducing global convergence in practice are proposed. Numerical results on the MacMPEC test problem set demonstrate the fast-local convergence properties of the algorithm.

A Multifunctional Characterization Test Bench for Shape Memory Alloy Micro-Wires : Design, Implementation and Validation

Most relevant to predicting the behavior of shape-memory-alloy (SMA)-based actuatorsensor applications activated by Joule heating are the electro-mechanical characteristics of the material under consideration. For a comprehensive characterization, a single setup that is able to provide all relevant data and information is desirable. This work covers the design, implementation and validation of such a high-end test bench for the holistic characterization of SMA micro-wires. In addition, the setup provides the possibility of application simulation experiments. Key elements of the design are the clamping mechanism guided on air bearings, a linear direct drive, a high-resolution load cell, a high-precision constant current source and a stress-controlled in-line wire sample installation. All measurements take place inside an isolated, temperature-controlled chamber. With the presented setup, the electro-mechanical and thermal characteristics of SMA wire samples with diameters from 20 µm to 100 µm can be determined. Via hardware-in-the-loop (HiL) implementation, the outputs with different biasing mechanisms and additional end-stops can be simulated even at high ambient temperatures. The generated results facilitate the prediction of the exact characteristics of SMA-driven actuator-sensor systems in a variety of applications and lead to a better general understanding of the alloy’s properties. All functionalities and features of the setup are presented by discussing the results of exemplary experiments

An optically pumped magnetometer working in the light-shift dispersed Mz mode

We present an optically pumped magnetometer working in a new operational mode— the light-shift dispersed Mz (LSD-Mz) mode. It is realized combining various features; (1) high power off-resonant optical pumping; (2) Mz configuration, where pumping light and magnetic field of interest are oriented parallel to each other; (3) use of small alkali metal vapor cells of identical properties in integrated array structures, where two such cells are pumped by circularly polarized light of opposite helicity; and (4) subtraction of the Mz signals of these two cells. The LSD-Mz magnetometer’s performance depends on the inherent and very complex interplay of input parameters. In order to find the configuration of optimal magnetometer resolution, a sensitivity analysis of the input parameters by means of Latin Hypercube Sampling was carried out. The resulting datasets of the multi-dimensional parameter space exploration were assessed by a subsequent physically reasonable interpretation. Finally, the best shot-noise limited magnetic field resolution was determined within that parameter space. As the result, using two 50 mm3 integrated vapor cells a magnetic field resolution below 10 fT/√Hz at Earth’s magnetic field strength is possible

How artificial intelligence and machine learning can help healthcare systems respond to COVID-19

The COVID-19 global pandemic is a threat not only to the health of millions of individuals, but also to the stability of infrastructure and economies around the world. The disease will inevitably place an overwhelming burden on healthcare systems that cannot be effectively dealt with by existing facilities or responses based on conventional approaches. We believe that a rigorous clinical and societal response can only be mounted by using intelligence derived from a variety of data sources to better utilize scarce healthcare resources, provide per- sonalized patient management plans, inform policy, and expedite clinical trials. In this paper, we introduce five of the most important challenges in responding to COVID-19 and show how each of them can be addressed by recent develop- ments in machine learning (ML) and artificial intelligence (AI). We argue that the integration of these techniques into local, national, and international healthcare systems will save lives, and propose specific methods by which implementation can happen swiftly and efficiently. We offer to extend these resources and knowledge to assist policymakers seeking to implement these techniques

Prevalence and incidence of antibodies against SARS-CoV-2 among primary healthcare providers in Belgium during 1 year of the COVID-19 epidemic: prospective cohort study protocol.

peer reviewed[en] INTRODUCTION: National SARS-CoV-2 seroprevalence data provide essential information about population exposure to the virus and help predict the future course of the epidemic. Early cohort studies have suggested declines in levels of antibodies in individuals associated with, for example, illness severity, age and comorbidities. This protocol focuses on the seroprevalence among primary healthcare providers (PHCPs) in Belgium. PHCPs manage the vast majority of (COVID-19) patients and therefore play an essential role in the efficient organisation of healthcare. Currently, evidence is lacking on (1) how many PHCPs get infected with SARS-CoV-2 in Belgium, (2) the rate at which this happens, (3) their clinical spectrum, (4) their risk factors, (5) the effectiveness of the measures to prevent infection and (6) the accuracy of the serology-based point-of-care test (POCT) in a primary care setting. METHODS AND ANALYSIS: This study will be set up as a prospective cohort study. General practitioners (GPs) and other PHCPs (working in a GP practice) will be recruited via professional networks and professional media outlets to register online to participate. Registered GPs and other PHCPs will be asked at each testing point (n=9) to perform a capillary blood sample antibody POCT targeting IgM and IgG against the receptor-binding domain of SARS-CoV-2 and complete an online questionnaire. The primary outcomes are the prevalence and incidence of antibodies against SARS-CoV-2 in PHCPs during a 12-month follow-up period. Secondary outcomes include the longevity of antibodies against SARS-CoV-2. ETHICS AND DISSEMINATION: Ethical approval has been granted by the ethics committee of the University Hospital of Antwerp/University of Antwerp (Belgian registration number: 3002020000237). Alongside journal publications, dissemination activities include the publication of monthly reports to be shared with the participants and the general population through the publicly available website of the Belgian health authorities (Sciensano). TRIAL REGISTRATION NUMBER: NCT04779424

Validation of a rapid SARS-CoV-2 antibody test in general practice.

peer reviewed[en] OBJECTIVES: To validate a rapid serological test (RST) for SARS-CoV-2 antibodies used in seroprevalence studies in healthcare providers, including primary healthcare providers (PHCPs) in Belgium. DESIGN: A phase III validation study of the RST (OrientGene) within a prospective cohort study. SETTING: Primary care in Belgium. PARTICIPANTS: Any general practitioner (GP) working in primary care in Belgium and any other PHCP from the same GP practice who physically manages patients were eligible in the seroprevalence study. For the validation study, all participants who tested positive (376) on the RST at the first testing timepoint (T1) and a random sample of those who tested negative (790) and unclear (24) were included. INTERVENTION: At T2, 4 weeks later, PHCPs performed the RST with fingerprick blood (index test) immediately after providing a serum sample to be analysed for the presence of SARS-CoV-2 immunoglobulin G antibodies using a two-out-of-three assay (reference test). PRIMARY AND SECONDARY OUTCOME MEASURES: The RST accuracy was estimated using inverse probability weighting to correct for missing reference test data, and considering unclear RST results as negative for the sensitivity and positive for the specificity. Using these conservative estimates, the true seroprevalence was estimated both for T2 and RST-based prevalence values found in a cohort study with PHCPs in Belgium. RESULTS: 1073 paired tests (403 positive on the reference test) were included. A sensitivity of 73% (a specificity of 92%) was found considering unclear RST results as negative (positive). For an RST-based prevalence at T1 (13.9), T2 (24.9) and T7 (70.21), the true prevalence was estimated to be 9.1%, 25.9% and 95.7%, respectively. CONCLUSION: The RST sensitivity (73%) and specificity (92%) make an RST-based seroprevalence below (above) 23% overestimate (underestimate) the true seroprevalence. TRIAL REGISTRATION NUMBER: NCT04779424

SARS-CoV-2 seroprevalence among vaccinated nursing home residents and staff in Belgium in August 2021

The SCOPE study assesses the prevalence of anti-SARS-CoV-2 antibodies among a representative sample of residents and staff in Belgian NH (nursing homes). Starting from February 1st 2021, a cohort of 1,640 residents and 1.368 staff members in 69 Belgian NHs are being tested every two months on the presence of anti-SARS-CoV-2 antibodies. This brief communication reports on the prevalence of anti-SARS-CoV-2 antibodies among vaccinated nursing home residents and staff. At the end of April 2021, the large scale vaccination campaign in Belgian nursing homes, which took place between January 5th and March 24th 2021, resulted in a vaccination coverage of 97% in NH residents and 84% in staff members. For these vaccinated groups, we describe the prevalence of anti-SARS-CoV-2 antibodies immediately following the vaccination campaign (April, 2021) and the seroprevalence evolution over the two following testing periods (in June and August 2021). Data collection of the August 2021 testing period was not finished at the time of compiling this brief communication. The August 2021 testing period comprises the data from 65 out of the 69 nursing homes. Additionally, some antibody test results are expected the coming weeks in case of self-sampling (for staff in particular). Results given here are preliminary. Small adaptations in some data might occur in future reports.SCOP