Environmental effects on the incidence of spontaneous pneumothorax

Spontaneous pneumothorax (SP) is a common occurrence especially in young male asthmatics and smokers. Several studies have shown that this condition occurs in clusters although other reports showed the contrary. There is evidence that clustering of cases occur as a result of severe changes in atmospheric pressure. The literature is however very limited with regards to the relationship between air pollution and spontaneous pneumothorax. Methodology: Observational study on consecutive patients admitted with SP from January 2010 to December 2014. The data regarding dates of admissions, gender, age, residential address, smoking history, relevant medical history and sequential management of the pneumothorax were collected and tabulated. The admission dates were analysed to test for clustering of admissions of patients. The patients were identified by location to assess the incidence of SP in different locations or areas. The Environment and Resources Agency (ERA) of Malta supplied daily particulate data from 3 different sites in the archipelago for the years 2010-1014. Results: There were 112 patients presenting with 134 episodes of SP. The mean age was 29 years and 86.6% were males. No admission date clustering occurred and therefore linkage to atmospheric pressure changes cannot be made. There was however a very significant increase in incidence in patients hailing from the harbour area (p < 0:00001). ERA data shows that there was a similarly significant increase in particulate material in the air of the harbour locality when compared to non- harbour areas. Discussion and Conclusion: SP is commoner in men and smokers. There was no evidence of admission day clustering but areas with increased air particulate matter had an increased incidence of patients with SP. Increased air pollution seems to increase the incidence of SP either directly or indirectly.peer-reviewe

Dual adaptive dynamic control of mobile robots using neural networks

This paper proposes two novel dual adaptive neural control schemes for the dynamic control of nonholonomic mobile robots. The two schemes are developed in discrete time, and the robot's nonlinear dynamic functions are assumed to be unknown. Gaussian radial basis function and sigmoidal multilayer perceptron neural networks are used for function approximation. In each scheme, the unknown network parameters are estimated stochastically in real time, and no preliminary offline neural network training is used. In contrast to other adaptive techniques hitherto proposed in the literature on mobile robots, the dual control laws presented in this paper do not rely on the heuristic certainty equivalence property but account for the uncertainty in the estimates. This results in a major improvement in tracking performance, despite the plant uncertainty and unmodeled dynamics. Monte Carlo simulation and statistical hypothesis testing are used to illustrate the effectiveness of the two proposed stochastic controllers as applied to the trajectory-tracking problem of a differentially driven wheeled mobile robot.peer-reviewe

Of mice and mates:Automated classification and modelling of mouse behaviour in groups using a single model across cages

Behavioural experiments often happen in specialised arenas, but this may confound the analysis. To address this issue, we provide tools to study mice in the home-cage environment, equipping biologists with the possibility to capture the temporal aspect of the individual’s behaviour and model the interaction and interdependence between cage-mates with minimal human intervention. Our main contribution is the novel Global Behaviour Model (GBM) which summarises the joint behaviour of groups of mice across cages, using a permutation matrix to match the mouse identities in each cage to the model. In support of the above, we also (a) developed the Activity Labelling Module (ALM) to automatically classify mouse behaviour from video, and (b) released two datasets, ABODe for training behaviour classifiers and IMADGE for modelling behaviour

A combined EEG motor and speech imagery paradigm with automated successive halving for customizable command selection

The classification performance of endogenous electroencephalogram (EEG) brain-computer interfaces (BCIs) can be improved by hybridizing the paradigm through the use of commands from multiple paradigms. Hybrid paradigms using motor imagery (MI) and speech imagery (SI) have shown promise, but there is a lack of research into: i) their effectiveness when compared to pure MI and SI for multiclass problems, and ii) automated command selection. This study investigates multiclass MI and SI hybrid paradigms and compares the results to those obtained using pure MI and SI. Performance was assessed using F1 score and accuracy. The performances of all possible hybrid paradigm designs were assessed. The analysis indicated that hybridization does not always guarantee improved performance when compared to the pure paradigms, and there is inter-subject variation in the best paradigm. This confirmed the need for automated subject-specific hybrid paradigm designs. An automated hybrid paradigm selection technique using successive halving (SH) for expedited computational times was developed and results were compared to those obtained using a standard grid search. The SH approach resulted in an improvement in F1 score of 21.09% and 36.86% compared to MI and SI and led to a reduction in computational times of 82.80% compared to grid search.peer-reviewe

Towards intelligent early form design and prototyping, questionnaire results and analysis

Currently, the Department of Manufacturing Engineering (DME), University of Malta and the Istitito per la Matematica Applicata e Tecnologie Informatiche (IMATI), Genoa are conducting research on how simple components represented by sketches on normal paper can be converted to computer models. One of the key issues in developing a sketch recognition system is precisely to handle the trade-off between ease of computer recognition and the preservation of sketching freedom. With an attempt to address this issue, two sketching methods (or sketching languages) have been developed by the DME. This report presents the results of a questionnaire about the sketching activity itself and also about the two proposed sketching languages. An analysis of the results obtained is also presented with the scope to identify what should be the future directions that might contribute to enhance the usefulness of the two sketching approaches

A comprehensive review of endogenous EEG-based BCIs for dynamic device control

Electroencephalogram (EEG)-based brain–computer interfaces (BCIs) provide a novel approach for controlling external devices. BCI technologies can be important enabling technologies for people with severe mobility impairment. Endogenous paradigms, which depend on user-generated commands and do not need external stimuli, can provide intuitive control of external devices. This paper discusses BCIs to control various physical devices such as exoskeletons, wheelchairs, mobile robots, and robotic arms. These technologies must be able to navigate complex environments or execute fine motor movements. Brain control of these devices presents an intricate research problem that merges signal processing and classification techniques with control theory. In particular, obtaining strong classification performance for endogenous BCIs is challenging, and EEG decoder output signals can be unstable. These issues present myriad research questions that are discussed in this review paper. This review covers papers published until the end of 2021 that presented BCI-controlled dynamic devices. It discusses the devices controlled, EEG paradigms, shared control, stabilization of the EEG signal, traditional machine learning and deep learning techniques, and user experience. The paper concludes with a discussion of open questions and avenues for future work.peer-reviewe

Relativistic quantum theories and neutrino oscillations

Neutrino oscillations are examined under the broad requirements of Poincar\'e-invariant scattering theory in an S-matrix formulation. This approach can be consistently applied to theories with either field or particle degrees of freedom. The goal of this paper is to use this general framework to identify all of the unique physical properties of this problem that lead to a simple oscillation formula. We discuss what is in principle observable, and how many factors that are important in principle end up being negligible in practice.Comment: 21 pages, no figure

Nhar San Duminku tal-Birgu

Ġabra ta’ poeżiji u proża li tinkludi: Imħabba u lwien ta’ Dun Frans Camilleri – Il-lum u l-bieraħ ta’ Rużar Briffa – Issa li.... ta’ K. Vassallo – Imħabba taħt siġra ta’ Vincent Caruana – Morna għall-bebbux ta’ Ġużi Abela – Ward fuq qabri ta’ Pawlu Aquilina – Nhar San Duminku tal-Birgu ta’ Val. V. Barbara.N/

New X-ray observations of the old nova CP Puppis and of the more recent nova V351 Pup

We present X-ray observations of the field containing Nova Puppis 1942 (CP Pup) and Nova Puppis 1991 (V351 Pup), done with ASCA in 1998, and with XMM-Newton in 2005. The X-ray and UV luminosity of CP Pup seem to have remained approximately constant since the last X-ray observations of the 1980'ies, while the optical luminosity has decreased. The X-ray properties of this nova are explained by a high mass white dwarf accreting at low rate, in agreement with the nova theory given the large amplitude and other characteristics of the 1942 outburst. Assuming a distance of 1600 pc, the X-ray luminosity of CP Pup is L=2.2 x 10(33) erg/s in the 0.15-10 keV range covered with EPIC, compatible with a magnetic system. The RGS grating spectrum shows a few prominent emission lines, and it is fitted with a cooling flow with mass accretion rate mdot <= 1.6 x 10(-10) msol/year. We detected also the O VII complex at 21.6-21.8 A that does not arise in the cooling flow. Most likely this feature originates in a wind or in the nova shell. The RGS and EPIC spectra are fitted only with thermal models with a very high shock temperature, T>60 keV, indicating a white dwarf with M>1.1 M(sun). The X-ray flux is modulated with the spectroscopic period of 1.47 hours detected in the optical. Since CP Pup is not an eclipsing system, this is better understood if magnetic accretion occurs: we discuss this possibility and its implications in detail. V351 Pup (N Pup 1991) was detected with XMM-Newton, but not with ASCA. It is a faint, non-super-soft X-ray source with luminosity L(x) =~ 3 x 10(31) erg/s, a factor of 50 less than measured with ROSAT in 1993.Comment: in press on the Astrophysical Journa