Naresuan University Journal
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Electrically evoked compound action potentials artefact rejection by independent component analysis: procedure automation.
No full textBACKGROUND: Independent-components-analysis (ICA) successfully separated electrically-evoked compound action potentials (ECAPs) from the stimulation artefact and noise (ECAP-ICA, Akhoun et al., 2013). NEW METHOD: This paper shows how to automate the ECAP-ICA artefact cancellation process. Raw-ECAPs without artefact rejection were consecutively recorded for each stimulation condition from at least 8 intra-cochlear electrodes. Firstly, amplifier-saturated recordings were discarded, and the data from different stimulus conditions (different current-levels) were concatenated temporally. The key aspect of the automation procedure was the sequential deductive source categorisation after ICA was applied with a restriction to 4 sources. The stereotypical aspect of the 4 sources enables their automatic classification as two artefact components, a noise and the sought ECAP based on theoretical and empirical considerations. RESULTS: The automatic procedure was tested using 8 cochlear implant (CI) users and one to four stimulus electrodes. The artefact and noise sources were successively identified and discarded, leaving the ECAP as the remaining source. The automated ECAP-ICA procedure successfully extracted the correct ECAPs compared to standard clinical forward masking paradigm in 22 out of 26 cases. COMPARISON WITH EXISTING METHOD(S): ECAP-ICA does not require extracting the ECAP from a combination of distinct buffers as it is the case with regular methods. It is an alternative that does not have the possible bias of traditional artefact rejections such as alternate-polarity or forward-masking paradigms. CONCLUSIONS: The ECAP-ICA procedure bears clinical relevance, for example as the artefact rejection sub-module of automated ECAP-threshold detection techniques, which are common features of CI clinical fitting software
Synthetic biology advances for pharmaceutical production
No full textSynthetic biology enables a new generation of microbial engineering for the biotechnological production of pharmaceuticals and other high-value chemicals. This review presents an overview of recent advances in the field, describing new computational and experimental tools for the discovery, optimization and production of bioactive molecules, and outlining progress towards the application of these tools to pharmaceutical production systems
Chemical determinants of occupational hypersensitivity pneumonitis.
No full textBACKGROUND: Workplace inhalational exposures to low molecular weight (LMW) chemicals cause hypersensitivity pneumonitis (HP) as well as the more common manifestation of respiratory hypersensitivity, occupational asthma (OA). AIMS: To explore whether chemical causation of HP is associated with different structural and physico-chemical determinants from OA. METHODS: Chemical causes of human cases of HP and OA were identified from searches of peer-reviewed literature up to the end of 2011. Each chemical was categorized according to whether or not it had been the attributed cause of at least one case of HP. The predicted asthma hazard was determined for each chemical using a previously developed quantitative structure-activity relationship (QSAR) model. The chemicals in both sets were independently and 'blindly' analysed by an expert in mech anistic chemistry for a qualitative prediction of protein cross-linking potential and determination of lipophilicity (log K ow). RESULTS: Ten HP-causing chemicals were identified and had a higher median QSAR predicted asthma hazard than the control group of 101 OA-causing chemicals (P <0.01). Nine of 10 HP-causing chemicals were predicted to be protein cross-linkers compared with 24/92 controls (P <0.001). The distributions of log K ow indicated higher values for the HP list (median 3.47) compared with controls (median 0.81) (P <0.05). CONCLUSIONS: These findings suggest that chemicals capable of causing HP tend to have higher predicted asthma hazard, are more lipophilic and are more likely to be protein cross-linkers than those causing OA
Effectiveness of Case Management for 'At Risk' Patients in Primary Care: A Systematic Review and Meta-Analysis
No full textBackground An ageing population with multimorbidity is putting pressure on health systems. A popular method of managing this pressure is identification of patients in primary care 'at-risk' of hospitalisation, and delivering case management to improve outcomes and avoid admissions. However, the effectiveness of this model has not been subjected to rigorous quantitative synthesis. Methods and Findings We carried out a systematic review and meta-analysis of the effectiveness of case management for 'at-risk' patients in primary care. Six bibliographic databases were searched using terms for 'case management', 'primary care', and a methodology filter (Cochrane EPOC group). Effectiveness compared to usual care was measured across a number of relevant outcomes: Health - self-assessed health status, mortality; Cost - total cost of care, healthcare utilisation (primary and non-specialist care and secondary care separately), and; Satisfaction patient satisfaction. We conducted secondary subgroup analyses to assess whether effectiveness was moderated by the particular model of case management, context, and study design. A total of 15,327 titles and abstracts were screened, 36 unique studies were included. Meta-analyses showed no significant differences in total cost, mortality, utilisation of primary or secondary care. A very small significant effect favouring case management was found for self-reported health status in the short-term (0.07, 95% CI 0.00 to 0.14). A small significant effect favouring case management was found for patient satisfaction in the short- (0.26, 0.16 to 0.36) and long-term (0.35, 0.04 to 0.66). Secondary subgroup analyses suggested the effectiveness of case management may be increased when delivered by a multidisciplinary team, when a social worker was involved, and when delivered in a setting rated as low in initial 'strength' of primary care. Conclusions This was the first meta-analytic review which examined the effects of case management on a wide range of outcomes and considered also the effects of key moderators. Current results do not support case management as an effective model, especially concerning reduction of secondary care use or total costs. We consider reasons for lack of effect and highlight key research questions for the future. Review Protocol The review protocol is available as part of the PROSPERO database (registration number: CRD42014010824)
The impact of patient timetables, therapeutic group work, patient-led therapy and structured social activity during in-patient stroke rehabilitation: A Phase I modelling study
No full text
Differential persistence of four biologic therapies for the treatment of moderate-to-severe psoriasis: a prospective observational cohort study from the British Association of Dermatologists Biologic Interventions Register
No full textExact SINR Statistics in the Presence of Heterogeneous Interferers
No full textWe derive new results for the higher-order moments of signal-to-interference-plus-noise ratio (SINR) in the presence of an arbitrary Poisson point process (PPP)-based heterogeneous interference field. The analysis leverages on a momentgenerating-function (MGF) methodology which only requires the statistics of intended signal and aggregate interference, thus eliminating the need for the exact distribution of SINR. We extend the existing results on interference statistics by deriving a generalized closed-form expression of the interference MGF considering Nakagami-m fading channels with exclusion region. In certain special cases, explicit expressions for the averages of different functions of SINR are found which also lead to closed form solutions for the probability distributions of aggregate interference reciprocal and signal-to-interference ratio (SIR). We prove that in such cases the effect of total PPP-based interference power on useful transmission is mathematically equivalent to the severe fluctuations from a one-sided Gaussian fading channel. As an application example, the proposed methodology is used together with stochastic geometry theory to characterize the average SINR and rate in heterogeneous cellular networks (HetNets). The validity of our analytical derivations is confirmed via Monte-Carlo simulations for various system settings.We show that with cellular network densification there exists a trade-off between the average SINR and rate performance