The Association between Daytime Napping and Cognitive Functioning in Chronic Fatigue Syndrome

OBJECTIVES The precise relationship between sleep and physical and mental functioning in chronic fatigue syndrome (CFS) has not been examined directly, nor has the impact of daytime napping. This study aimed to examine self-reported sleep in patients with CFS and explore whether sleep quality and daytime napping, specific patient characteristics (gender, illness length) and levels of anxiety and depression, predicted daytime fatigue severity, levels of daytime sleepiness and cognitive functioning, all key dimensions of the illness experience. METHODS 118 adults meeting the 1994 CDC case criteria for CFS completed a standardised sleep diary over 14 days. Momentary functional assessments of fatigue, sleepiness, cognition and mood were completed by patients as part of usual care. Levels of daytime functioning and disability were quantified using symptom assessment tools, measuring fatigue (Chalder Fatigue Scale), sleepiness (Epworth Sleepiness Scale), cognitive functioning (Trail Making Test, Cognitive Failures Questionnaire), and mood (Hospital Anxiety and Depression Scale). RESULTS Hierarchical Regressions demonstrated that a shorter time since diagnosis, higher depression and longer wake time after sleep onset predicted 23.4% of the variance in fatigue severity (p <.001). Being male, higher depression and more afternoon naps predicted 25.6% of the variance in objective cognitive dysfunction (p <.001). Higher anxiety and depression and morning napping predicted 32.2% of the variance in subjective cognitive dysfunction (p <.001). When patients were classified into groups of mild and moderate sleepiness, those with longer daytime naps, those who mainly napped in the afternoon, and those with higher levels of anxiety, were more likely to be in the moderately sleepy group. CONCLUSIONS Napping, particularly in the afternoon is associated with poorer cognitive functioning and more daytime sleepiness in CFS. These findings have clinical implications for symptom management strategies

Focus variation measurement of electron beam melted surfaces

Electron beam melting (EBM) is a promising additive manufacturing process which is seeing increasing use in high value manufacturing sectors such as aerospace [1]. With its layer-by-layer approach, EBM can allow the creation of parts of complex shapes, thus reducing the need for assembly [2]. Surface topography measurement of EBM parts is gaining an increasingly important role, both for assessing the surface finishes that can be obtained with the process before and after post-processing, and as a useful tool to investigate how the manufacturing process behaves through the observation of surface features produced (observation of the manufacturing process signature or fingerprint) [3]. EBM surfaces are very complex and irregular, with a large number of high slopes and undercuts [4]. It is, therefore, very difficult to measure the surface topography of an EBM part. Optical technologies for areal topography measurement are now popular, thanks to their capability for fast acquisition of dense data sets [5]. Focus variation (FV) is one of the most promising measurement technologies for EBM parts, as it combines reasonably fast measurement times with good capability to capture complex topographies [6]. However, many possible FV set-ups could be adopted for measuring an EBM surface. Objective lens magnification, illumination conditions and detector parameters are some of the most relevant control variables that can be varied, in the attempt to achieve optimal measurement results

Focus variation measurement of electron beam melted surfaces

Electron beam melting (EBM) is a promising additive manufacturing process which is seeing increasing use in high value manufacturing sectors such as aerospace [1]. With its layer-by-layer approach, EBM can allow the creation of parts of complex shapes, thus reducing the need for assembly [2]. Surface topography measurement of EBM parts is gaining an increasingly important role, both for assessing the surface finishes that can be obtained with the process before and after post-processing, and as a useful tool to investigate how the manufacturing process behaves through the observation of surface features produced (observation of the manufacturing process signature or fingerprint) [3]. EBM surfaces are very complex and irregular, with a large number of high slopes and undercuts [4]. It is, therefore, very difficult to measure the surface topography of an EBM part. Optical technologies for areal topography measurement are now popular, thanks to their capability for fast acquisition of dense data sets [5]. Focus variation (FV) is one of the most promising measurement technologies for EBM parts, as it combines reasonably fast measurement times with good capability to capture complex topographies [6]. However, many possible FV set-ups could be adopted for measuring an EBM surface. Objective lens magnification, illumination conditions and detector parameters are some of the most relevant control variables that can be varied, in the attempt to achieve optimal measurement results

Small volume laboratory on a chip measurements incorporating the quartz crystal microbalance to measure the viscosity-density product of room temperature ionic liquids

A microfluidic glass chip system incorporating a quartz crystal microbalance (QCM) to measure the square root of the viscosity-density product of room temperature ionic liquids (RTILs) is presented. The QCM covers a central recess on a glass chip, with a seal formed by tightly clamping from above outside the sensing region. The change in resonant frequency of the QCM allows for the determination of the square root viscosity-density product of RTILs to a limit of ∼ 10 kg m−2 s−0.5. This method has reduced the sample size needed for characterization from 1.5 ml to only 30 μl and allows the measurement to be made in an enclosed system

Feature-based characterisation of evolving surface topographies in finishing operations for additive manufacturing

Finishing operations play a fundamental role in the additive manufacture of components. Conventional surface metrology solutions allow for the characterisation of surface roughness through texture parameters, but are not fully suitable to capture the evolution of individual surface topographic formations as they undergo changes as a result of finishing operations. Feature-based characterisation of topography offers a new perspective in the investigation of surfaces. The approach consists of the identification, isolation, and dimensional characterisation of surface topography formations (surface features). In this work an original feature- based solution is proposed for the quantitative comparison of topographies before and after a finishing operation: the approach is based on the registration of areal topography datasets and quantitative analysis of shape and size differences pertaining to the relevant topographic features. A variety of finishing operations are investigated on metallic samples manufactured via powder bed fusion

Recovery Assessment Scale - Domains and Stages (RAS-DS) Manual - Version 2

Manual to guide administration of the Recovery Assessment Scale - Domains and Stages (RAS-DS). The RAS-DS has 38 items or statements for the consumer to rate. It is a Likert scale with 4 rating categories for consumers to select from: “untrue”; “a bit true”; “mostly true” and “completely true”. The items have been divided into 4 recovery domains: Doing Things I Value (functional recovery); Looking Forward (personal recovery); Mastering My Illness (clinical recovery) and Connecting and Belonging (social recovery)

SU-8 Guiding Layer for Love Wave Devices

SU-8 is a technologically important photoresist used extensively for the fabrication of microfluidics and MEMS, allowing high aspect ratio structures to be produced. In this work we report the use of SU-8 as a Love wave sensor guiding layer which allows the possibility of integrating a guiding layer with flow cell during fabrication. Devices were fabricated on ST-cut quartz substrates with a single-single finger design such that a surface skimming bulk wave (SSBW) at 97.4 MHz was excited. SU-8 polymer layers were successively built up by spin coating and spectra recorded at each stage; showing a frequency decrease with increasing guiding layer thickness. The insertion loss and frequency dependence as a function of guiding layer thickness was investigated over the first Love wave mode. Mass loading sensitivity of the resultant Love wave devices was investigated by deposition of multiple gold layers. Liquid sensing using these devices was also demonstrated; water-glycerol mixtures were used to demonstrate sensing of density-viscosity and the physical adsorption and removal of protein was also assessed using albumin and fibrinogen as model proteins