Impact of Therapeutic Inertia on Long-Term Blood Pressure Control: A Monte Carlo Simulation Study.

[Figure: see text].

Deep learning with wearable based heart rate variability for prediction of mental and general health.

The ubiquity and commoditisation of wearable biosensors (fitness bands) has led to a deluge of personal healthcare data, but with limited analytics typically fed back to the user. The feasibility of feeding back more complex, seemingly unrelated measures to users was investigated, by assessing whether increased levels of stress, anxiety and depression (factors known to affect cardiac function) and general health measures could be accurately predicted using heart rate variability (HRV) data from wrist wearables alone. Levels of stress, anxiety, depression and general health were evaluated from subjective questionnaires completed on a weekly or twice-weekly basis by 652 participants.

Future technology on the flight deck: assessing the use of touchscreens in vibration environments.

Use of touchscreens in the flight deck has been steadily increasing, however, their usability may be severely impacted when turbulent conditions arise. Most previous research focusses on using touchscreens in static conditions; therefore, this study assessed touchscreen use whilst undergoing turbulent representative motion, generated using a 6-axis motion simulator. Touchscreens were tested in centre, side and overhead positions, to investigate how turbulence affected: (1) error rate, movement times and accuracy, (2) arm fatigue and discomfort.

Local Variation in Femoral Neck Cortical Bone: In Vitro Measured Bone Mineral Density, Geometry and Mechanical Properties.

Age- and disease (osteoporotic fractured and osteoarthritic tissue)-related changes in the distribution of cortical bone were examined, using a multimodality approach, including measurement of local density, geometry and mechanical properties, where changes in these properties can give rise to instability and increasing probability of fracture. In contrast to the majority of previously reported research, this study also focuses on the characteristic non-circular femoral neck cross-sectional geometry and variation in bone mineral density (BMD) around the femoral neck. Twenty-two osteoarthritic and 7 osteoporotic femoral neck slices, collected from elective and trauma-related arthroplasty, and 16 cadaveric donor tissue controls were tested mechanically using Reference Point Indentation (BioDent™, Active Life Technologies®, Santa Barbara, CA) and then scanned with in vitro-based radiography intended to replicate the dual-energy X-ray absorptiometry technique.

Site-Dependent Reference Point Microindentation Complements Clinical Measures for Improved Fracture Risk Assessment at the Human Femoral Neck.

In contrast to traditional approaches to fracture risk assessment using clinical risk factors and bone mineral density (BMD), a new technique, reference point microindentation (RPI), permits direct assessment of bone quality; in vivo tibial RPI measurements appear to discriminate patients with a fragility fracture from controls. However, it is unclear how this relates to the site of the most clinically devastating fracture, the femoral neck, and whether RPI provides information complementary to that from existing assessments. Femoral neck samples were collected at surgery after low-trauma hip fracture (n = 46; 17 male; aged 83 [interquartile range 77-87] years) and compared, using RPI (Biodent Hfc), with 16 cadaveric control samples, free from bone disease (7 male; aged 65 [IQR 61-74] years).

Feasibility of skin surface elastography by tracking skin surface topography.

Recent advances have led to a multitude of image modalities being used for visualization of tissue stiffness. High-resolution images of tissue stiffness are desirable, as they have the potential to provide useful diagnostic information. A noncontact optical imaging method has the attractions of low cost, simplicity, and utility when skin contact is undesirable.

Discomfort and the cortical haemodynamic response to coloured gratings.

In five experiments we measured the amplitude of the haemodynamic response to visual patterns using near infrared spectroscopy of the visual cortex. The patterns were gratings with bars that differed in chromaticity but not in luminance. In all experiments, with a wide range of chromaticities of the grating bars, the amplitude of the haemodynamic response increased with the separation of the chromaticities in the CIE 1976 UCS diagram.

Time course of the haemodynamic response to visual stimulation in migraine, measured using near-infrared spectroscopy.

Background: In patients with migraine, an abnormally large haemodynamic response to epileptogenic visual stimulation has previously been observed, consistent with the hypothesis of a cortical hyperexcitability. Ophthalmic filters have been used in the treatment of migraine, and they reduce the haemodynamic response.

Methods: The present study used near-infrared spectroscopy (NIRS) to characterise the haemodynamic response to a range of visual stimuli in 20 patients with migraine (15 with aura and 5 without) and paired controls in order to assess the effect of ophthalmic treatment.

Multi-directional in vivo tensile skin stiffness measurement for the design of a reproducible tensile strain elastography protocol.

Background/aims: Elastography is a promising new medical imaging modality, displaying spatial distribution of biomechanical properties such as local tissue strain response to an applied stress. To develop a reproducible test protocol for skin elastography, the effect of various parameters on skin stiffness measurements was investigated.

Methods: The parameters investigated were: history of skin loading before test loading (preconditioning), direction of test loading (anisotropy) and posture (pre-stress).

Reflectance of human skin using colour photometric stereo: with particular application to pigmented lesion analysis.

Background/purpose: The optical appearance of human skin is highly dependent on the interaction between the illumination (type and position), observer position and the skin surface structure. Different currently available photographic techniques record different aspects of this appearance, each providing its own incomplete description. This limits their usefulness, especially for pigmented skin lesion diagnosis.