The perfect recovery? Interactive influence of perfectionism and spillover work tasks on changes in exhaustion and mood around a vacation

This study examined week-level changes in affective well-being among school teachers as they transitioned into and out of a 1-week vacation. In addition, we investigated the interactive influence of personality characteristics (specifically perfectionism) and spillover work activities during the vacation on changes in teachers' well-being. A sample of 224 teachers completed study measures across 7 consecutive weeks, spanning the period before, during, and after a midterm vacation (providing a total of 1,525 responses across the study period). Results obtained from discontinuous multilevel growth models revealed evidence of a vacation effect, indicated by significant reductions in emotional exhaustion, anxiety, and depressed mood from before to during the vacation. Across 4 working weeks following the vacation, exhaustion and negative mood exhibited a nonlinear pattern of gradual convergence back to prevacation levels. Teachers with a higher level of perfectionistic concerns experienced elevated working week levels of exhaustion, anxious mood, and depressed mood, followed by pronounced reductions in anxious and depressed mood as they transitioned into the vacation. However, a strongly beneficial effect of the vacation was only obtained by perfectionistic teachers who refrained from spillover work tasks during the vacation. This pattern of findings is consistent with a diathesis-stress model, in that the perfectionists' vulnerability was relatively dormant (or deactivated) during a respite from job demands. Our results may provide an explanation for why engaging in work-related activities during vacations has previously exhibited weak relationships with employees' recovery and well-being

Modelling drug delivery to the small airways: optimization using response surface methodology

Aim: The aim of this in silico study was to investigate the effect of particle size, flow rate, and tidal volume on drug targeting to small airways in patients with mild COPD. Method: Design of Experiments (DoE) was used with an in silico whole lung particle deposition model for bolus administration to investigate whether controlling inhalation can improve drug delivery to the small conducting airways. The range of particle aerodynamic diameters studied was 0.4 – 10 µm for flow rates between 100 – 2000 mL/s (i.e., low to very high), and tidal volumes between 40 – 1500 mL. Results: The model accurately predicted the relationship between independent variables and lung deposition, as confirmed by comparison with published experimental data. It was found that large particles (~ 5 µm) require very low flow rate (~ 100 mL/s) and very small tidal volume (~ 110 mL) to target small conducting airways, whereas fine particles (~ 2 µm) achieve drug targeting in the region at a relatively higher flow rate (~ 500 mL/s) and similar tidal volume (~ 110 mL). Conclusion: The simulation results indicated that controlling tidal volume and flow rate can achieve targeted delivery to the small airways (i.e., > 50% of emitted dose was predicted to deposit in the small airways), and the optimal parameters depend on the particle size. It is hoped that this finding could provide a means of improving drug targeting to the small conducting airways and improve prognosis in COPD management

Novel preparation of controlled porosity particle/fibre loaded scaffolds using a hybrid micro-fluidic and electrohydrodynamic technique.

The purpose of this research was to produce multi-dimensional scaffolds containing biocompatible particles and fibres. To achieve this, two techniques were combined and used: T-Junction microfluidics and electrohydrodynamic (EHD) processing. The former was used to form layers of monodispersed bovine serum albumin (BSA) bubbles, which upon drying formed porous scaffolds. By altering the T-Junction processing parameters, bubbles with different diameters were produced and hence the scaffold porosity could be controlled. EHD processing was used to spray or spin poly(lactic-co-glycolic) (PLGA), polymethysilsesquioxane (PMSQ) and collagen particles/fibres onto the scaffolds during their production and after drying. As a result, multifunctional BSA scaffolds with controlled porosity containing PLGA, PMSQ and collagen particles/fibres were obtained. Product morphology was studied by optical and scanning electron microscopy. These products have potential applications in many advanced biomedical, pharmaceutical and cosmetic fields e.g. bone regeneration, drug delivery, cosmetic cream lathers, facial scrubbing creams etc

The effect of needle tip displacement in co-axial electrohydrodynamic processing

Co-axial electrospraying and electrospinning are versatile electrohydrodynamic (EHD) techniques that can be used to encapsulate a variety of materials in the form of polymeric particles and fibres via a one step process. The successful production of uniform encapsulated products in co-axial EHD (CEHD) processing depends on multiple parameters including solution concentration, applied voltage and needle capillary diameter. Although many studies have been conducted to investigate the effects of these parameters, there has been very limited research on how the axial displacement between the two needle tips affects the final products formed. Hence the purpose of this study was to adjust the positioning of the inner needle such that its tip extends beyond, is level with or resides inside that of the outer needle and to thus determine the most effective arrangement for controlling product size, uniformity and/or yield. Core–shell particles were prepared using two polymers, poly(lactic-co-glycolic)acid (PLGA) as the shell and polymethylsilsesquioxane (PMSQ) as the core and core–shell fibres using PMSQ as the shell and a volatile liquid, perfluorohexane (PFH) as the core. The products formed were analyzed by optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After analysis, it was concluded that the most effective arrangement for generating both particles and fibres with the optimal combination of size, uniformity and yield was to have the inner needle 2 mm inside the outer needle. This allows for formation of a stable cone–jet and successful encapsulation of the inner liquid within the outer liquid, before the outer stable cone–jet forms. The corresponding collected product diameter and percentage of products in which material was successfully encapsulated were found to be 0.6 ± 0.1 μm and 85 ± 3% respectively for particles and 9 ± 1 μm and 92 ± 2% for fibres

Microfluidic system for high throughput characterisation of echogenic particles

Echogenic particles, such as microbubbles and volatile liquid micro/nano droplets, have shown considerable potential in a variety of clinical diagnostic and therapeutic applications. The accurate prediction of their response to ultrasound excitation is however extremely challenging, and this has hindered the optimisation of techniques such as quantitative ultrasound imaging and targeted drug delivery. Existing characterisation techniques, such as ultra-high speed microscopy provide important insights, but suffer from a number of limitations; most significantly difficulty in obtaining large data sets suitable for statistical analysis and the need to physically constrain the particles, thereby altering their dynamics. Here a microfluidic system is presented that overcomes these challenges to enable the measurement of single echogenic particle response to ultrasound excitation. A co-axial flow focusing device is used to direct a continuous stream of unconstrained particles through the combined focal region of an ultrasound transducer and a laser. Both the optical and acoustic scatter from individual particles are then simultaneously recorded. Calibration of the device and example results for different types of echogenic particle are presented, demonstrating a high throughput of up to 20 particles per second and the ability to resolve changes in particle radius down to 0.1 μm with an uncertainty of less than 3%

Psychometric properties of the Hospital Survey on Patient Safety Culture: findings from the UK

Background: Patient safety culture is measured using a range of survey tools. Many provide limited data on psychometric properties and few report findings outside of the USA healthcare context. This study reports an assessment of the psychometric properties and suitability of the American Hospital Survey on Patient Safety Culture (HSOPC) for use within the UK. Methods: A questionnaire survey of three hospitals within a large UK Acute NHS Trust. 1,437 questionnaires were completed (37% response rate). Exploratory factor analysis, confirmatory factor analysis, and reliability analyses were carried out to assess the psychometric performance of this survey instrument and explore potential improvements. Results: Reliability analysis of the items within each proposed scale showed that over half failed to achieve satisfactory internal consistency (Cronbach’s Alpha < 0.7). Furthermore, a confirmatory factor analysis carried out on the UK dataset achieved a poor fit when compared to the original American model. An optimal measurement model was then constructed via exploratory and confirmatory factor analysis with split-half sample validation, and consisted of 9 dimensions compared to the original 12 in the American model. Conclusion: This is one of the few studies to provide an evaluation of an American patient safety culture survey using data from the UK. The results indicate that there is need for caution in using the HSOPC survey in the UK and underline the importance of appropriate validation of safety culture surveys before extending their usage to populations outside of the specific geographical and health care contexts in which they were developed

Relationships between two dimensions of employee perfectionism, postwork cognitive processing, and work day functioning

This daily diary study examined relations between two distinct perfectionism dimensions and work-related cognitions experienced by employees during evening leisure time. Drawing from perseverative cognitive processing theory, we hypothesized that perfectionistic concerns would be related to work-related worry and rumination during postwork evenings. In contrast, we hypothesized that a theoretically more adaptive perfectionist dimension (perfectionistic strivings) would be associated with positively valenced self-reflections about work across consecutive evenings. A sample of 148 full-time workers completed an initial survey, which included a trait perfectionism measure, reported their work-related cognitions across four consecutive evenings of a working week, rated their sleep quality immediately upon awakening on each subsequent morning, and their daily levels of emotional exhaustion and work engagement at the end of each work day. Results showed that perfectionistic concerns were indirectly negatively associated with sleep quality and work day functioning via the tendency to worry and ruminate about work. In contrast, perfectionistic strivings were indirectly positively associated with work day engagement via the propensity to experience positive thoughts about work during evening leisure time. The theoretical and practical implications of these findings are discussed