Surface Modification of Electrospun PVDF/PAN Nanofibrous Layers by Low Vacuum Plasma Treatment

Nanofibres are very promising for water remediation due to their high porosity and small pore size. Mechanical properties of nanofibres restrict the application of pressure needed water treatments. Various PAN, PVDF, and PVDF/PAN nanofibre layers were produced, and mechanical properties were improved via a lamination process. Low vacuum plasma treatment was applied for the surface modification of nanofibres. Atmospheric air was used to improve hydrophilicity while sulphur hexafluoride gas was used to improve hydrophobicity of membranes. Hydrophilic membranes showed higher affinity to attach plasma particles compared to hydrophobic membranes

Validation of asthma recording in electronic health records: protocol for a systematic review.

BACKGROUND: Asthma is a common, heterogeneous disease with significant morbidity and mortality worldwide. It can be difficult to define in epidemiological studies using electronic health records as the diagnosis is based on non-specific respiratory symptoms and spirometry, neither of which are routinely registered. Electronic health records can nonetheless be valuable to study the epidemiology, management, healthcare use and control of asthma. For health databases to be useful sources of information, asthma diagnoses should ideally be validated. The primary objectives are to provide an overview of the methods used to validate asthma diagnoses in electronic health records and summarise the results of the validation studies. METHODS: EMBASE and MEDLINE will be systematically searched for appropriate search terms. The searches will cover all studies in these databases up to October 2016 with no start date and will yield studies that have validated algorithms or codes for the diagnosis of asthma in electronic health records. At least one test validation measure (sensitivity, specificity, positive predictive value, negative predictive value or other) is necessary for inclusion. In addition, we require the validated algorithms to be compared with an external golden standard, such as a manual review, a questionnaire or an independent second database. We will summarise key data including author, year of publication, country, time period, date, data source, population, case characteristics, clinical events, algorithms, gold standard and validation statistics in a uniform table. ETHICS AND DISSEMINATION: This study is a synthesis of previously published studies and, therefore, no ethical approval is required. The results will be submitted to a peer-reviewed journal for publication. Results from this systematic review can be used to study outcome research on asthma and can be used to identify case definitions for asthma. PROSPERO REGISTRATION NUMBER: CRD42016041798

Validation of asthma recording in the Clinical Practice Research Datalink (CPRD)

OBJECTIVES: The optimal method of identifying people with asthma from electronic health records in primary care is not known. The aim of this study is to determine the positive predictive value (PPV) of different algorithms using clinical codes and prescription data to identify people with asthma in the United Kingdom Clinical Practice Research Datalink (CPRD). METHODS: 684 participants registered with a general practitioner (GP) practice contributing to CPRD between 1 December 2013 and 30 November 2015 were selected according to one of eight predefined potential asthma identification algorithms. A questionnaire was sent to the GPs to confirm asthma status and provide additional information to support an asthma diagnosis. Two study physicians independently reviewed and adjudicated the questionnaires and additional information to form a gold standard for asthma diagnosis. The PPV was calculated for each algorithm. RESULTS: 684 questionnaires were sent, of which 494 (72%) were returned and 475 (69%) were complete and analysed. All five algorithms including a specific Read code indicating asthma or non-specific Read code accompanied by additional conditions performed well. The PPV for asthma diagnosis using only a specific asthma code was 86.4% (95% CI 77.4% to 95.4%). Extra information on asthma medication prescription (PPV 83.3%), evidence of reversibility testing (PPV 86.0%) or a combination of all three selection criteria (PPV 86.4%) did not result in a higher PPV. The algorithm using non-specific asthma codes, information on reversibility testing and respiratory medication use scored highest (PPV 90.7%, 95% CI (82.8% to 98.7%), but had a much lower identifiable population. Algorithms based on asthma symptom codes had low PPVs (43.1% to 57.8%)%). CONCLUSIONS: People with asthma can be accurately identified from UK primary care records using specific Read codes. The inclusion of spirometry or asthma medications in the algorithm did not clearly improve accuracy. ETHICS AND DISSEMINATION: The protocol for this research was approved by the Independent Scientific Advisory Committee (ISAC) for MHRA Database Research (protocol number15_257) and the approved protocol was made available to the journal and reviewers during peer review. Generic ethical approval for observational research using the CPRD with approval from ISAC has been granted by a Health Research Authority Research Ethics Committee (East Midlands-Derby, REC reference number 05/MRE04/87).The results will be submitted for publication and will be disseminated through research conferences and peer-reviewed journals

Concomitant diagnosis of asthma and COPD:a quantitative study in UK primary care

Background: Asthma and chronic obstructive pulmonary disease (COPD) share many characteristics and symptoms, and the differential diagnosis between the two diseases can be difficult in primary care. This study explored potential overlap between both diseases in a primary care environment.Aim: To quantify how commonly patients with COPD have a concomitant diagnosis of asthma, and how commonly patients with asthma have a concomitant diagnosis of COPD in UK primary care. Additionally, the study aimed to determine the extent of possible misdiagnosis and missed opportunities for diagnosis.Design and setting: Patients with validated asthma and patients with validated COPD in primary care were identified from the UK Clinical Practice Research Datalink (CPRD) in separate validation studies, and the diseases were confirmed by review of GP questionnaires.Method: The prevalence of concurrent asthma and COPD in validated cases of either disease was examined based on CPRD coding, GP questionnaires, and requested additional information.Results: In total, 400 patients with COPD and 351 patients with asthma in primary care were identified. Of the patients with validated asthma, 15% (n = 52) had previously received a diagnostic COPD Read code, although COPD was only likely in 14.8% (95% confidence interval [CI] = 11.3 to 19.0) of patients with validated asthma. More than half (52.5%, n = 210) of patients with validated COPD had previously received a diagnostic asthma Read code. However, when considering additional evidence to support a diagnosis of asthma, concurrent asthma was only likely in 14.5% (95% CI = 11.2 to 18.3) of patients with validated COPD.Conclusion: A concurrent asthma and COPD diagnosis appears to affect a relative minority of patients with COPD (14.5%) or asthma (14.8%). Asthma diagnosis may be over-recorded in people with COPD.</p

Monitoring of polarization-based effects in fiber-optic transmission link caused by environmental variations

The fast transmission of signals around the globe is fundamental to the flow of information for our society. A long-haul transmission certainly represents one of the key advancements that shaped modern ways of communicating and offers a nearly instant access to any available data or a latest information. However, fiber-optic transmission typically suffers from a variety of physical impairments that degrade the signal quality, thus imposing limits on both, the achievable transmission capacity and data reach. Of particular concerns are stochastic fiber impairments, primarily represented by polarization mode dispersion (PMD). The PMD originates from a random birefringence caused by imperfect fiber circularity and other, both internal and external, effects, basically completely re-defining the light polarization state of output signal compared to its initial counterpart. The PMD is particularly critical as it restricts operation of fiber-optic links running at speeds higher than 10 Gbps. This, in turn, hinders fiber link re-adaption towards higher transmission bit rates in future, however. In this context, both in-line link monitoring and testing of PMD-based effects is of great importance within the recently used optical fiber links. However, polarization-based effects are also very sensitive to the environmental changes, substantially degrading transmitted optical signals and reducing link quality. In this work, we provide experimental characterization for PMD-based propagation effects in optical fibers influenced by wind gusts. The investigation was performed on commercially used fiber-optic link that runs through optical power ground wire cables. The 111-km-long optical link under study comprised installed optical fibers with available 88 channels. Here, we monitored environmental changes caused by wind conditions over several consecutive days with a 60 second time frame and sensed PMD impact on the link performance. Here, differential group delay (DGD) was chosen to be a key parameter, enabling for sensitive characterization of wind related link changes. Measured maximum DGD’s were 4 and 10 ps for wind speeds up to 5 and 20 m/s, respectively. In addition, experimentally measured data were used in numerical model to assess the optical link quality. For a low wind condition, we observed negligible quality degradation in the optical link, considering transmission bit rates of 10, 40, and 100 Gbps. Conversely, in case of strong wind condition, the optical link maintained a reliable operation only for established 10 Gbps, while significant link degradation was observed for bit rates of 40 and 100 Gbps. Our work shows promising way to effectively sense and monitor undesired environmental variations and their impact on polarization-based fiber link propagation effects, which in turn, can allow an instant link quality evaluation