Understanding barriers and enablers to participation in a proposed online lifestyle intervention for older adults with age-related macular degeneration to guide programme implementation.

Age-related macular degeneration (AMD) is a blinding condition associated with depression, loneliness and unhealthy lifestyle behaviours which drives AMD progression. We have proposed the first online lifestyle intervention for AMD, called Movement, Interaction and Nutrition for Greater Lifestyles in the Elderly (MINGLE) to promote positive lifestyle changes and reduce loneliness. This qualitative grounded-theory study explored enablers and barriers to future participation in MINGLE for older adults with AMD. Thirty-one participants were interviewed and thematic analysis revealed nine themes. Enablers to participation were: socialising and learning about AMD, motivation to improve health, programme accessibility and structure. Barriers were: lack of time, technology, limited knowledge regarding holistic interventions, vision-related issues, mobility and negative perception of group interactions. These factors must be considered when developing lifestyle interventions for AMD patients to maximise participation. Supporting technology use and raising awareness about benefits of healthy lifestyle behaviours for AMD may help overcome these barriers.

Tailoring 3D Speckle Statistics.

We experimentally generate three-dimensional speckles with customized intensity statistics. By appropriately modulating the phase front of a laser beam, the far-field speckles can maintain a desired intensity probability density function upon axial propagation: while evolving into different spatial patterns. We also demonstrate how to design speckle patterns that obtain distinct tailored intensity statistics on multiple designated axial planes. The ability to design 3D speckle statistics opens many possibilities: three-dimensional imaging and sensing, optical trapping, and manipulation.

Single-mode regenerative amplification in multimode fiber.

The peak power performance of ultrafast fiber lasers scales with fiber mode area, but large fibers host multiple modes that are difficult to control. We demonstrate a technique for single-mode operation of highly multimode fiber based on regenerative amplification. This results in a short-pulse fiber source with, to our knowledge, an unprecedented combination of features: high gain (>55 dB) with negligible amplified spontaneous emission, high pulse energy (>50 µJ), good beam quality (M2 ≤ 1.3), and transform-limited (300 fs) pulses from a single amplification stage. We discuss peak intensity scaling to much higher levels and other opportunities for short-pulse generation in regenerative fiber amplifiers.

Coherent enhancement of optical remission in diffusive media.

Remitted waves are used for sensing and imaging in diverse diffusive media from the Earth's crust to the human brain. Separating the source and detector increases the penetration depth of light, but the signal strength decreases rapidly, leading to a poor signal-to-noise ratio. Here, we show, experimentally and numerically, that wavefront shaping a laser beam incident on a diffusive sample enables an enhancement of remission by an order of magnitude at depths of up to 10 transport mean free paths. We develop a theoretical model which predicts the maximal remission enhancement. Our analysis reveals a significant improvement in the sensitivity of remitted waves to local changes of absorption deep inside diffusive media. This work illustrates the potential of coherent wavefront control for noninvasive diffuse wave imaging applications, such as diffuse optical tomography and functional near-infrared spectroscopy.

Sum rules for energy deposition eigenchannels in scattering systems.

In a random-scattering system, the deposition matrix maps the incident wavefront onto the internal field distribution across a target volume. The corresponding eigenchannels have been used to enhance the wave energy delivered to the target. Here, we find the sum rules for the eigenvalues and eigenchannels of the deposition matrix in any system geometry: including two- and three-dimensional scattering systems, as well as narrow waveguides and wide slabs. We derive a number of constraints on the eigenchannel intensity distributions inside the system as well as the corresponding eigenvalues. Our results are general and applicable to random systems of arbitrary scattering strength as well as different types of waves including electromagnetic waves, acoustic waves, and matter waves.

Development, implementation and evaluation of the online Movement, Interaction and Nutrition for Greater Lifestyles in the Elderly (MINGLE) program: The protocol for a pilot trial.

INTRODUCTION: People with age-related macular degeneration (AMD) are more likely to experience loneliness, have poorer diets and be less physically active than people without AMD. The online Movement, Interaction and Nutrition for Greater Lifestyles in the Elderly (MINGLE) program is a holistic evidence-based intervention aiming to support people with AMD by incorporating physical activity, social interaction and nutrition education components all delivered via a COVID-19-safe Zoom platform. This study will involve two phases: 1) a formative qualitative study with AMD patients to identify the barriers and facilitators to participating in the proposed MINGLE program; and 2) a 10-week pilot study to evaluate the feasibility, acceptability and preliminary efficacy of MINGLE. METHODS AND ANALYSIS: Phase 1 involves AMD patients who will be recruited from an eye clinic in Western Sydney, Australia to participate in audio-recorded semi-structured interviews. Verbatim interview transcripts will be coded using the Capability, Opportunity, Motivation and Behaviour (COM-B) model and themes established. These themes will be used as a guide to specifically tailor the proposed MINGLE program to people with AMD. Phase 2 involves 52 AMD patients who will then be recruited from the same clinic to participate in the MINGLE program. Pre-post questionnaires will be administered to intervention participants to collect information on the following variables: demographics, socioeconomic status, vision function, loneliness, quality of life (including depression), falls risk, physical activity (level), and dietary intake. The acceptability and feasibility of the MINGLE program will also be evaluated using descriptive statistics. TRIAL REGISTRATION NUMBER: ACTRN12621000939897p.

Diabetes SPECIAL (Students Providing Education on Chronic Illness and Lifestyle): a novel preclinical medical student elective.

BACKGROUND: Traditional medical student curricula limit substantial clinical experiences until the third and fourth years of medical school. This delay in valuable experiences hinders the ability of some medical students to choose a specialty to pursue, delays the formation of meaningful longitudinal mentorship relationships, and limits the development of important clinical acumen. Furthermore, the use of medical students in preclinical years may help to improve patient care and outcomes. APPROACH: The novel preclinical Diabetes SPECIAL (Students Providing Education on Chronic Illness and Lifestyle) elective was designed to introduce first year medical students to the field of endocrinology, promote the development of a professional identity, improve medical student communication skills, and raise awareness of the complexities of managing patients living with diabetes mellitus. Furthermore, and novel to this experience, was to measure the impact of this elective on patient outcomes. EVALUATION: Students attended patient appointments, communicated with their assigned patients regularly, relayed important health information to the attending endocrinologist, and attended monthly didactic sessions. The elective outcomes were evaluated via completed surveys by patients, students, and attending physicians as well as medical record review for pre- and post-elective hemoglobin A1C levels. REFLECTION: Students, faculty, and patients who participated in this elective generally reported having a positive experience. Seven out of 10 patients had a reduction in their hemoglobin A1C levels. The outcomes from the pilot of this novel preclinical elective support the importance of early clinical exposure in medical student training and highlight potential positive impacts on both medical student education and patient outcomes.

Fluctuations and Correlations of Transmission Eigenchannels in Diffusive Media.

Selective excitation of a diffusive system's transmission eigenchannels enables manipulation of its internal energy distribution. The fluctuations and correlations of the eigenchannel's spatial profiles, however, remain unexplored so far. Here we show that the depth profiles of high-transmission eigenchannels exhibit low realization-to-realization fluctuations. Furthermore, our experimental and numerical studies reveal the existence of interchannel correlations, which are significant for low-transmission eigenchannels. Because high-transmission eigenchannels are robust and independent from other eigenchannels, they can reliably deliver energy deep inside turbid media.

Introducing non-local correlations into laser speckles.

Laser speckles have become a fundamental component of the modern optics-research toolbox. Not only are speckle patterns the basis of numerous imaging techniques, but also, they are employed to generate optical potentials for cold atoms and colloidal particles. The ability to manipulate a speckle pattern's spatial intensity correlations, particularly long-range (non-local) ones, is essential in numerous applications. A typical fully-developed speckle pattern, however, only possesses short-ranged (local) intensity correlations which are determined by the spatial field correlations. Here we experimentally demonstrate and theoretically develop a general method for creating fully-developed speckles with strong non-local intensity correlations. The functional form of the spatial intensity correlations can be arbitrarily tailored without altering the field correlations. Our approach provides a versatile and utilitarian framework for enhancing and controlling non-local correlations in speckle patterns.

Engineering wavefront caustics trajectories in PT-symmetric lattices.

We utilize caustic theory in PT-symmetric lattices to design focusing and curved beam dynamics. We show that the gain and loss parameter in these systems provides an additional degree of freedom that allows for the design of the same caustics trajectories with different intensity distribution in the individual waveguides. Moreover we can create aberration-free focal points at any paraxial distance z(f), with anomalously large focal intensity.