The unfolding low-carbon transition in the UK electricity system.

The paper explores three periods in the UK electricity consumption-production system since World War II. The first two involved the development of an increasingly centralized, integrated system that provided electricity to meet growing post-war demand. It saw two major changes in governance, first to nationalization, then to privatization and liberalization. The third period started at the turn of the Century, driven by increasing evidence of the impact of fossil fuels on the Earth's climate. The paper focuses on the drivers of change, within the UK and externally, and how they affected governance, technology deployment, and industry structure. It draws on the multi-level perspective and the concepts of governance and technological branching points to inform the analysis of each period. It shows that there is a considerable distance to travel toward a truly sustainable electricity system.

Financial risk allocation and provider incentives in hospital-insurer contracts in The Netherlands.

In healthcare systems with a purchaser-provider split, contracts are an important tool to define the conditions for the provision of healthcare services. Financial risk allocation can be used in contracts as a mechanism to influence provider behavior and stimulate providers to provide efficient and high-quality care. In this paper, we provide new insights into financial risk allocation between insurers and hospitals in a changing contracting environment. We used unique nationwide data from 901 hospital-insurer contracts in The Netherlands over the years 2013, 2016, and 2018. Based on descriptive and regression analyses, we find that hospitals were exposed to more financial risk over time, although this increase was somewhat counteracted by an increasing use of risk-mitigating measures between 2016 and 2018. It is likely that this trend was heavily influenced by national cost control agreements. In addition, alternative payment models to incentivize value-based health care were rarely used and thus seemingly of lower priority, despite national policies being explicitly directed at this goal. Finally, our analysis shows that hospital and insurer market power were both negatively associated with financial risk for hospitals. This effect becomes stronger if both hospital and insurer have strong market power, which in this case may indicate a greater need to reduce (financial) uncertainties and to create more cooperative relationships.

An agenda for future Social Sciences and Humanities research on energy efficiency: 100 priority research questions.

Decades of techno-economic energy policymaking and research have meant evidence from the Social Sciences and Humanities (SSH)-including critical reflections on what changing a society's relation to energy (efficiency) even means-have been underutilised. In particular, (i) the SSH have too often been sidelined and/or narrowly pigeonholed by policymakers, funders, and other decision-makers when driving research agendas, and (ii) the setting of SSH-focused research agendas has not historically embedded inclusive and deliberative processes. The aim of this paper is to address these gaps through the production of a research agenda outlining future SSH research priorities for energy efficiency. A Horizon Scanning exercise was run, which sought to identify 100 priority SSH questions for energy efficiency research. This exercise included 152 researchers with prior SSH expertise on energy efficiency, who together spanned 62 (sub-)disciplines of SSH, 23 countries, and a full range of career stages. The resultant questions were inductively clustered into seven themes as follows: (1) Citizenship, engagement and knowledge exchange in relation to energy efficiency; (2) Energy efficiency in relation to equity, justice, poverty and vulnerability; (3) Energy efficiency in relation to everyday life and practices of energy consumption and production; (4) Framing, defining and measuring energy efficiency; (5) Governance, policy and political issues around energy efficiency; (6) Roles of economic systems, supply chains and financial mechanisms in improving energy efficiency; and (7) The interactions, unintended consequences and rebound effects of energy efficiency interventions. Given the consistent centrality of energy efficiency in policy programmes, this paper highlights that well-developed SSH approaches are ready to be mobilised to contribute to the development, and/or to understand the implications, of energy efficiency measures and governance solutions. Implicitly, it also emphasises the heterogeneity of SSH policy evidence that can be produced. The agenda will be of use for both (1) those new to the energy-SSH field (including policyworkers), for learnings on the capabilities and capacities of energy-SSH, and (2) established energy-SSH researchers, for insights on the collectively held futures of energy-SSH research.

Delirium in HIV-infected patients admitted to acute medical wards post universal access to antiretrovirals in South Africa.

BACKGROUND: Delirium is associated with increased mortality and length of hospital stay. Limited data are available from HIV-infected acute hospital admissions in developing countries. We conducted a prospective study of delirium among acute medical admissions in South Africa (SA), a developing country with universal antiretroviral therapy (ART) access and high burdens of tuberculosis (TB) and non-communicable disease. OBJECTIVES: To identify the prevalence of, risk factors for and outcomes of delirium in HIV-infected individuals in acute general medical admissions. METHODS: Three cohorts of adult acute medical admissions to Groote Schuur and Victoria Wynberg hospitals, Cape Town, SA, were evaluated for prevalent delirium within 24 hours of admission. Reference delirium testing was performed by either consultant physicians or neuropsychologists, using the Confusion Assessment Method. RESULTS: The study included 1 182 acute medical admissions, with 318 (26.9%) HIV-infected. The median (interquartile range) age and CD4 count were 35 (30 - 43) years and 132 (61 - 256) cells/µL, respectively, with 140/318 (44.0%) using ART on admission. The prevalence of delirium was 17.6% (95% confidence interval (CI) 13.7 - 22.1) among HIV-infected patients, and delirium was associated with increased inpatient mortality. In multivariable logistic regression analysis, factors associated with delirium were age ≥55 years (adjusted odds ratio (aOR) 6.95 (95% CI 2.03 - 23.67); p=0.002), and urea ≥15 mmol/L (aOR 4.83 (95% CI 1.7 - 13.44); p=0.003), while ART use reduced risk (p=0.014). A low CD4 count, an unsuppressed viral load and active TB were not predictors of delirium; nor were other previously reported risk factors such as non-opportunistic acute infections or polypharmacy. CONCLUSIONS: Delirium is common and is associated with increased mortality in HIV-infected acute medical admissions in endemic settings, despite increased ART use. Older HIV-infected patients with renal dysfunction are at increased risk for inpatient delirium, while those using ART on admission have a reduced risk.

Experimental Evaluation of Smartphone Accelerometer and Low-Cost Dual Frequency GNSS Sensors for Deformation Monitoring.

Smartphone accelerometers and low-cost Global Navigation Satellite System (GNSS) equipment have faced rapid and important advancement, opening a new door to deformation monitoring applications such as landslide, plate tectonics and structural health monitoring (SHM). The precision potential and operational feasibility of the equipment play an important role in the decision making of campaigning for affordable solutions. This paper focuses on the evaluation of the empirical precision, including (auto)time correlation, of a common smartphone accelerometer (Bosch BMI160) and a low-cost dual frequency GNSS reference-rover pair (u-blox ZED-F9P) set to operate at high rates (50 and 5 Hz, respectively). Additionally, a high-rate (5 Hz) GPS-only baseline-based multipath (MP) correction is proposed for effectively removing a large part of this error and allowing to correctly determine the instrumental noise of the GNSS sensor. Furthermore, the benefit of smartphone-based validation for the tracking of dynamic displacements is addressed. The estimated East-North-Up (ENU) precision values (σ^) of ±7.7, 8.1 and 9.6 mms2 are comparable with the declared precision potential (σ) of the smartphone accelerometer of ±8.8mms2. Furthermore, the acceleration noise shows only mild traces of (auto)correlation. The MP-corrected 3D (ENU) empirical precision values of ±2.6, 3.6 and 6.7 mm were found to be better by 30-40% than the straight-out-of box precision of the GNSS sensor, attesting the usefulness of the MP correction. The GNSS sensors output position information with time correlation of typically tens of seconds. The results indicate exceptional precision potential of these low-power-consuming, small-scale, affordable sensors set to operate at a high-rate over small regions. The smartphone-based dynamic displacement validation shows that GNSS data of a low-cost sensor at a 5 Hz sampling rate can be successfully used for tracking dynamic processes.

Parasitological, serological, and molecular survey of trypanosomosis (Surra) in camels slaughtered in northwestern Nigeria.

Surra is a parasitic disease caused by Trypanosoma evansi and transmitted non-cyclically by biting flies. The disease significantly affects the health, productivity, and market value of camels thereby constituting a major constraint to food safety, security, and economy. This is the first study on the prevalence of surra in northwestern Nigeria, using a range of diagnostic tests along the parasitological-serological-molecular continuum hence, emphasizing it as a major enzootic risk for camels in Nigeria. In this cross-sectional study, 600 blood samples were collected from camels at major abattoirs in northwestern Nigeria and evaluated for the prevalence of T. evansi using parasitological (Giemsa staining), serological (CATT/T. evansi), and molecular (VSG-PCR and sequencing) methods. The overall prevalence of surra recorded in this study was 5.3%, 11.5%, and 22.5% using Giemsa-stained blood smears, CATT/T. evansi, and VSG-PCR respectively. However, higher prevalence rates at 6.0%, 13.7%, and 26.7% by Giemsa-stained blood smears, CATT/T. evansi, and VSG-PCR were recorded in Katsina State compared with results from Kano State. A significantly (p < 0.05) higher prevalence by VSG-PCR was observed when compared with both parasitological and serological methods used. Although age and body condition scores were associated (p < 0.05) with surra prevalence in sampled camels, no seasonal association (p > 0.05) was recorded. Sequencing of the VSG region of Trypanosoma spp. Further confirmed the presence of T. evansi as the aetiological agent of surra from the sampled camels. Findings from this study call for the implementation of adequate control measures aimed at reducing the impact of T. evansi infections on camel production in Nigeria.

Differentiating care for persons with mild intellectual disability or borderline intellectual functioning: a Delphi study on the opinions of primary and professional caregivers and scientists.

BACKGROUND: The demand for support for persons with mild intellectual disability or borderline intellectual functioning is growing rapidly. These persons often encounter individual and familial limitations that influence their human functioning, and often have difficulty coping with the demands of modern society. Although in the areas of policy, research and practice, people with mild intellectual disability or borderline intellectual functioning are generally approached as one group, important differences between them have been reported. Current support seems to be both suboptimal and insufficiently differentiated. METHODS: In this Delphi study we aimed to explore the need for appropriate and differentiated support for individuals with mild intellectual disability or borderline intellectual functioning. The study was based on five unique profiles of persons with mild intellectual disability or borderline intellectual functioning that are associated with individual and environmental variables. The opinions of expert primary caregivers, professional caregivers and scientists were analysed for potentially appropriate types of support for each of the five profiles. RESULTS: A total of 174 statements, divided over the five profiles, were presented to the participants. For 74 statements, consensus was reached between the expert groups. For each profile, these consensual statements represented specific items (e.g. concrete personal goals) and non-specific items (e.g. the attitude towards persons with mild intellectual disability or borderline intellectual functioning, and the coordination of health care) related to the support needs. CONCLUSION: This Delphi-based study generated consensual opinions contributing to a more differentiated system of support for individuals with mild intellectual disability or borderline intellectual functioning. Although these findings need additional investigation, they address actions that might enhance the support programmes for these individuals into more personalized support.

The N-formyl peptide receptors: contemporary roles in neuronal function and dysfunction.

N-formyl peptide receptors (FPRs) were first identified upon phagocytic leukocytes, but more than four decades of research has unearthed a plethora of non-myeloid roles for this receptor family. FPRs are expressed within neuronal tissues and markedly in the central nervous system, where FPR interactions with endogenous ligands have been implicated in the pathophysiology of several neurodegenerative diseases including Alzheimer's disease and Parkinson's disease, as well as neurological cancers such as neuroblastoma. Whilst the homeostatic function of FPRs in the nervous system is currently undefined, a variety of novel physiological roles for this receptor family in the neuronal context have been posited in both human and animal settings. Rapid developments in recent years have implicated FPRs in the process of neurogenesis and neuronal differentiation which, upon greater characterisation, could represent a novel pharmacological target for neuronal regeneration therapies that may be used in the treatment of brain/spinal cord injury, stroke and neurodegeneration. This review aims to summarize the recent progress made to determine the physiological role of FPRs in a neuronal setting, and to put forward a case for FPRs as a novel pharmacological target for conditions of the nervous system, and for their potential to open the door to novel neuronal regeneration therapies.

The formyl peptide receptor agonist FPRa14 induces differentiation of Neuro2a mouse neuroblastoma cells into multiple distinct morphologies which can be specifically inhibited with FPR antagonists and FPR knockdown using siRNA.

The N-formyl peptide receptors (FPRs) have been identified within neuronal tissues and may serve as yet undetermined functions within the nervous system. The FPRs have been implicated in the progression and invasiveness of neuroblastoma and other cancers. In this study the effects of the synthetic FPR agonist FPRa14, FPR antagonists and FPR knockdown using siRNA on mouse neuroblastoma neuro2a (N2a) cell differentiation plus toxicity were examined. The FPRa14 (1-10µM) was found to induce a significant dose-dependent differentiation response in mouse neuroblastoma N2a cells. Interestingly, three distinct differentiated morphologies were observed, with two non-archetypal forms observed at the higher FPRa14 concentrations. These three forms were also observed in the human neuroblastoma cell-lines IMR-32 and SH-SY5Y when exposed to 100µM FPRa14. In N2a cells combined knockdown of FPR1 and FPR2 using siRNA inhibited the differentiation response to FPRa14, suggesting involvement of both receptor subtypes. Pre-incubating N2a cultures with the FPR1 antagonists Boc-MLF and cyclosporin H significantly reduced FPRa14-induced differentiation to near baseline levels. Meanwhile, the FPR2 antagonist WRW4 had no significant effect on FPRa14-induced N2a differentiation. These results suggest that the N2a differentiation response observed has an FPR1-dependent component. Toxicity of FPRa14 was only observed at higher concentrations. All three antagonists used blocked FPRa14-induced toxicity, whilst only siRNA knockdown of FPR2 reduced toxicity. This suggests that the toxicity and differentiation involve different mechanisms. The demonstration of neuronal differentiation mediated via FPRs in this study represents a significant finding and suggests a role for FPRs in the CNS. This finding could potentially lead to novel therapies for a range of neurological conditions including neuroblastoma, Alzheimer's disease, Parkinson's disease and neuropathic pain. Furthermore, this could represent a potential avenue for neuronal regeneration therapies.

Association of Initiation of Maintenance Dialysis with Functional Status and Caregiver Burden.

BACKGROUND AND OBJECTIVES: Little is known about the functional course after initiating dialysis in elderly patients with ESKD. The aim of this study was to assess the association of the initiation of dialysis in an elderly population with functional status and caregiver burden. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS: This study included participants aged ≥65 years with ESKD who were enrolled in the Geriatric Assessment in Older Patients Starting Dialysis study. All underwent a geriatric assessment and a frailty screening (Fried Frailty Index and Groningen Frailty Indicator) at dialysis initiation. Functional status (activities of daily life and instrumental activities of daily life) and caregiver burden were assessed at baseline and after 6 months. Decline was defined as loss of one or more domains in functional status, stable as no difference between baseline and follow-up, and improvement as gain of one or more domains in functional status. Logistic regression was performed to assess the association between the combined outcome functional decline/death and potential risk factors. RESULTS: Of the 196 included participants functional data were available for 187 participants. Mean age was 75±7 years and 33% were women. At the start of dialysis, 79% were care dependent in functional status. After 6 months, 40% experienced a decline in functional status, 34% remained stable, 18% improved, and 8% died. The prevalence of high caregiver burden increased from 23%-38% (P=0.004). In the multivariable analysis age (odds ratio, 1.05; 95% confidence interval, 1.00 to 1.10 per year older at baseline) and a high Groningen Frailty Indicator compared with low score (odds ratio, 1.97; 95% confidence interval, 1.05 to 3.68) were associated with functional decline/death. CONCLUSIONS: In patients aged ≥65 years, functional decline within the first 6 months after initiating dialysis is highly prevalent. The risk is higher in older and frail patients. Loss in functional status was mainly driven by decline in instrumental activities of daily life. Moreover, initiation of dialysis is accompanied by an increase in caregiver burden.

Single-Epoch, Single-Frequency Multi-GNSS L5 RTK under High-Elevation Masking.

The Japanese Quasi-Zenith Satellite System (QZSS) satellite system has placed in orbit four satellites by October 2017. The Indian Regional Navigation Satellite System (IRNSS) system has launched the new satellite IRNNSS-11 in April 2018, completing seven operational satellites. Together with the GPS block IIF satellites and the Galileo satellites, four different global navigation satellite systems (GNSSs) are providing precise L5 signals on the frequency of 1176.45 MHz. In this contribution, we challenge the strength of the multi-GNSS model by analysing its single-frequency (L5), single-epoch (instantaneous) precise positioning capabilities under high-elevation masking (up to 40 degrees). With more satellites available, multi-GNSS real time kinematic (RTK) positioning is possible using L5-only signals with a high customary elevation mask. This helps to enable positioning in areas with constrained measurement geometry, and could significantly reduce the multipath effects in difficult measurement environments like urban canyons and mountainous areas. In this study, benefiting from the location of the Asia⁻Australia area, instantaneous multi-GNSS L5 RTK analysis is performed with respect to the ambiguity resolution and positioning performance. Formal results are shown and discussed for baselines located in different grids covering Australia, part of the Pacific Ocean, Indian Ocean and Asia, and empirical analysis is given for two baselines in Perth, Australia. Compared to the stand-alone cases, for baselines in Perth, it is shown that combining L5 signals from GPS/Galileo/QZSS/IRNSS significantly improves both the ambiguity success rates (ASR) and the positioning performance under high elevation mask. While the average single-system ASR is under 50% even with a low elevation mask of 10 degrees, combining all the four systems increases the ASR to above 95% under an elevation cut-off angles of 40 degrees. With an elevation mask of 40 degrees, using satellites from one system does not allow for meaningful positioning solutions of more than 8 h within the test day, while mm-to-cm level ambiguity-fixed standard deviations could be obtained based on the positioning results of almost the entire day when combining all the four systems. In addition to that, simulation was also performed for receivers with larger signal standard deviations, i.e., for low-cost receivers or receivers located in environments with larger multipath.

Cardiovascular Risk Management and Hepatitis C: Combining Drugs.

Direct-acting antivirals (DAAs) are known victims (substrate) and perpetrators (cause) of drug-drug interactions (DDIs). These DAAs are used for the treatment of hepatitis C virus (HCV) infections and are highly effective drugs. Drugs used for cardiovascular risk management are frequently used by HCV-infected patients, whom also are treated with DAAs. Therefore, the aim of this review was to describe DDIs between cardiovascular drugs (CVDs) and DAAs. An extensive literature search was performed containing search terms for the marketed DAAs and CVDs (ß-blocking agents, ACE inhibitors, angiotensin II antagonists, renin inhibitors, diuretics, calcium channel blockers, statins/ezetimibe, fibrates, platelet aggregation inhibitors, vitamin K antagonists, heparins, direct Xa inhibitors, nitrates, amiodarone, and digoxin). In particular, the drug labels from the European Medicines Agency and the US Food and Drug Administration were used. A main finding of this review is that CVDs are mostly victims of DDIs with DAAs. Therefore, when possible, monitoring of pharmacodynamics is recommended when coadministering these drugs with DAAs. Nevertheless, it is sometimes better to discontinue a drug on a temporary basis (statins, ezetimide). The DAAs are victims of DDIs in combination with bisoprolol, carvedilol, labetalol, verapamil, and gemfibrozil. Despite there are many DDIs predicted in this review, most of these DDIs can be managed by monitoring the efficacy and toxicity of the victim drug or by switching to another CVD/DAA.

A new approach to preferred provider selection in health care.

In January 2015 Zilveren Kruis, the largest health insurer in The Netherlands, engaged in a new three-year, unlimited volume contract with five carefully selected providers of cataract surgery. Zilveren Kruis used a novel method, designed to identify the top expert providers in a certain discipline. This procedure for provider selection uses the principles of Best Value Procurement (BVP), and puts the provider in charge of defining key performance indicators for health care quality. The procedure empowers the professional and acknowledges that the provider, not the purchaser, is the true expert in defining what is high quality care. This new approach focuses purely on provider selection and is thus complementary to innovations in health care reimbursement, such as value-based hospital purchasing or outcome-based financing. We describe this novel approach to preferred provider selection and show how it makes affordable quality the core topic in negotiations with providers.

Fast Phase-Only Positioning with Triple-Frequency GPS.

In this contribution, we study the phase-only ambiguity resolution and positioning performance of GPS for short baselines. It is well known that instantaneous (single-epoch) ambiguity resolution is possible when both phase and code (pseudorange) data are used. This requires, however, a benign multipath environment due to the severe effects multipath has on the code measurements. With phase-only processing, one would be free from such severe effects, be it that phase-only processing requires a change in receiver-satellite geometry, as a consequence of which it cannot be done instantaneously. It is thus of interest to know how much change in the relative receiver-satellite geometry is needed to achieve successful phase-only ambiguity resolution with correspondingly high precision baseline solutions. In this contribution, we study the two-epoch phase-only performance of single-, dual-, and triple-frequency GPS for varying time spans from 60 s down to 1 s. We demonstrate, empirically as well as formally, that fast phase-only very-precise positioning is indeed possible, and we explain the circumstances that make this possible. The formal analyses are also performed for a large area including Australia, a part of Asia, the Indian Ocean, and the Pacific Ocean. We remark that in this contribution "phase-only" refers to phase-only measurements in the observation model, while the code data are thus only used to compute the approximate values needed for linearizing the observation equations.

Hereditary angio-oedema in the Western Cape Province, South Africa.

BACKGROUND: Hereditary angio-oedema (HAE) is an autosomal dominant condition caused by a deficiency in the C1-esterase inhibitor protein, resulting in increased bradykinin release. It presents clinically with recurrent attacks of angio-oedema, commonly affecting the limbs, face, upper airway and gastrointestinal tract. Little is known about this condition in sub-Saharan Africa. OBJECTIVES: To analyse and report on the clinical presentation and treatment of patients with HAE in the Western Cape Province, South Africa. METHODS: A retrospective analysis was conducted on a series of 60 cases of HAE seen between 2010 and 2015 at the Allergy Diagnostic and Clinical Research Unit, University of Cape Town Lung Institute, and the Allergy Clinic at Groote Schuur Hospital, Cape Town. The findings in 43 cases of type 1 HAE are described. Parameters assessed included age, gender, age of diagnosis, duration of illness, family history, identifiable triggers, average duration of attack, number of attacks per year and type of attack. RESULTS: A total of 43 patients were included in this study. Of these, 65.1% (28/43) were female. The median age at diagnosis was 20 years (interquartile range (IQR) 10 - 27) and the median duration of illness 10.5 years (IQR 6 - 22). Of the patients, 62.8% (27/43), 32.6% (14/43) and 4.7% (2/43) were of mixed ancestry, white and black African, respectively; 51.2% (22/43) were index cases, with the remaining 48.8% (21/43) diagnoses via family member screening, 12 families making up the majority of the cohort. The mean (standard deviation) duration of an acute attack was 49 (25.8) hours, and 64.3% (27/42), 71.4% (30/42), 14.3% (6/42) and 88.1% (37/42) of patients experienced facial or upper airway, abdominal, external genitalia and limb attacks, respectively. Danazol for long-term prophylaxis was used in 21 patients, while C1-inhibitor concentrate (Berinert) was accessed for short-term prophylaxis in only four patients. Acute life-threating attacks were treated with fresh frozen plasma in 11 patients, and only four accessed icatibant. The mortality rate for the period 2010 - 2015 was 4.5% (2/43). The prevalence of HAE in the Western Cape was estimated to be 1:140 000. CONCLUSIONS: HAE occurs in South Africans of all ethnicities, and life-threatening attacks occur in almost two-thirds of patients. Despite limited therapeutic options and very limited access to gold-standard therapies available in the developed world, our mortality rate is very low, with both the deaths related to inability to access emergency treatment rapidly.

Multi-GNSS PPP-RTK: From Large- to Small-Scale Networks.

Precise point positioning (PPP) and its integer ambiguity resolution-enabled variant, PPP-RTK (real-time kinematic), can benefit enormously from the integration of multiple global navigation satellite systems (GNSS). In such a multi-GNSS landscape, the positioning convergence time is expected to be reduced considerably as compared to the one obtained by a single-GNSS setup. It is therefore the goal of the present contribution to provide numerical insights into the role taken by the multi-GNSS integration in delivering fast and high-precision positioning solutions (sub-decimeter and centimeter levels) using PPP-RTK. To that end, we employ the Curtin PPP-RTK platform and process data-sets of GPS, BeiDou Navigation Satellite System (BDS) and Galileo in stand-alone and combined forms. The data-sets are collected by various receiver types, ranging from high-end multi-frequency geodetic receivers to low-cost single-frequency mass-market receivers. The corresponding stations form a large-scale (Australia-wide) network as well as a small-scale network with inter-station distances less than 30 km. In case of the Australia-wide GPS-only ambiguity-float setup, 90% of the horizontal positioning errors (kinematic mode) are shown to become less than five centimeters after 103 min. The stated required time is reduced to 66 min for the corresponding GPS + BDS + Galieo setup. The time is further reduced to 15 min by applying single-receiver ambiguity resolution. The outcomes are supported by the positioning results of the small-scale network.

Identifying classes of persons with mild intellectual disability or borderline intellectual functioning: a latent class analysis.

BACKGROUND: Persons with mild intellectual disability or borderline intellectual functioning are often studied as a single group with similar characteristics. However, there are indications that differences exist within this population. Therefore, the aim of this study was to identify classes of persons with mild intellectual disability or borderline intellectual functioning and to examine whether these classes are related to individual and/or environmental characteristics. METHODS: Latent class analysis was performed using file data of 250 eligible participants with a mean age of 26.1 (SD 13.8, range 3-70) years. RESULTS: Five distinct classes of persons with mild intellectual disability or borderline intellectual functioning were found. These classes significantly differed in individual and environmental characteristics. For example, persons with a mild intellectual disability experienced fewer problems than those with borderline intellectual disability. CONCLUSIONS: The identification of five classes implies that a differentiated approach is required towards persons with mild intellectual disability or borderline intellectual functioning.

Does RAIM with Correct Exclusion Produce Unbiased Positions?

As the navigation solution of exclusion-based RAIM follows from a combination of least-squares estimation and a statistically based exclusion-process, the computation of the integrity of the navigation solution has to take the propagated uncertainty of the combined estimation-testing procedure into account. In this contribution, we analyse, theoretically as well as empirically, the effect that this combination has on the first statistical moment, i.e., the mean, of the computed navigation solution. It will be shown, although statistical testing is intended to remove biases from the data, that biases will always remain under the alternative hypothesis, even when the correct alternative hypothesis is properly identified. The a posteriori exclusion of a biased satellite range from the position solution will therefore never remove the bias in the position solution completely.

IRNSS/NavIC L5 Attitude Determination.

The Indian Regional Navigation Satellite System (IRNSS) has recently (May 2016) become fully-operational and has been provided with the operational name of NavIC (Navigation with Indian Constellation). It has been developed by the Indian Space Research Organization (ISRO) with the objective of offering positioning, navigation and timing (PNT) to the users in its service area. This contribution provides for the first time an assessment of the IRNSS L5-signal capability to achieve instantaneous attitude determination on the basis of data collected in Perth, Australia. Our evaluations are conducted for both a linear array of two antennas and a planar array of three antennas. A pre-requisite for precise and fast IRNSS attitude determination is the successful resolution of the double-differenced (DD) integer carrier-phase ambiguities. In this contribution, we will compare the performances of different such methods, amongst which the unconstrained and the multivariate-constrained LAMBDA method for both linear and planar arrays. It is demonstrated that the instantaneous ambiguity success rates increase from 15% to 90% for the linear array and from 5% to close to 100% for the planar array, thus showing that standalone IRNSS can realize 24-h almost instantaneous precise attitude determination with heading and elevation standard deviations of 0.05 and 0.10 degrees, respectively.

Automated chest-radiography as a triage for Xpert testing in resource-constrained settings: a prospective study of diagnostic accuracy and costs.

Molecular tests hold great potential for tuberculosis (TB) diagnosis, but are costly, time consuming, and HIV-infected patients are often sputum scarce. Therefore, alternative approaches are needed. We evaluated automated digital chest radiography (ACR) as a rapid and cheap pre-screen test prior to Xpert MTB/RIF (Xpert). 388 suspected TB subjects underwent chest radiography, Xpert and sputum culture testing. Radiographs were analysed by computer software (CAD4TB) and specialist readers, and abnormality scores were allocated. A triage algorithm was simulated in which subjects with a score above a threshold underwent Xpert. We computed sensitivity, specificity, cost per screened subject (CSS), cost per notified TB case (CNTBC) and throughput for different diagnostic thresholds. 18.3% of subjects had culture positive TB. For Xpert alone, sensitivity was 78.9%, specificity 98.1%, CSS $13.09 and CNTBC $90.70. In a pre-screening setting where 40% of subjects would undergo Xpert, CSS decreased to $6.72 and CNTBC to $54.34, with eight TB cases missed and throughput increased from 45 to 113 patients/day. Specialists, on average, read 57% of radiographs as abnormal, reducing CSS ($8.95) and CNTBC ($64.84). ACR pre-screening could substantially reduce costs, and increase daily throughput with few TB cases missed. These data inform public health policy in resource-constrained settings.