Measuring scattering distributions in scanning helium microscopy.

A scanning helium microscope typically utilises a thermal energy helium atom beam, with an energy and wavelength (¡100meV, ∼0.05 nm) particularly sensitive to surface structure. An angular detector stage for a scanning helium microscope is presented that facilitates the in-situ measurement of scattering distributions from a sample. We begin by demonstrating typical elastic and inelastic scattering from ordered surfaces. We then go on to show the role of topography in diffuse scattering from disordered surfaces, observing deviations from simple cosine scattering. In total, these studies demonstrate the wealth of information that is encoded into the scattering distributions obtained with the technique.

Observation of diffuse scattering in scanning helium microscopy.

In understanding the nature of contrast in the emerging field of neutral helium microscopy, it is important to identify if there is an atom-surface scattering distribution that can be expected to apply broadly across a range of sample surfaces. Here we present results acquired in a scanning helium microscope (SHeM) under typical operating conditions, from a range of surfaces in their native state, i.e. without any specialist sample preparation. We observe diffuse scattering, with an approximately cosine distribution centred about the surface normal. The 'cosine-like' distribution is markedly different from those distributions observed from the well-prepared, atomically pristine, surfaces typically studied in helium atom scattering experiments. Knowledge of the typical scattering distribution in SHeM experiments provides a starting basis for interpretation of topographic contrast in images, as well as a reference against which more exotic contrast mechanisms can be compared.

Standardizing resolution definition in scanning helium microscopy.

Resolution is a key parameter for microscopy, but methods for standardizing its definition are often poorly defined. For a developing technique such as scanning helium microscopy, it is critical that a consensus-based protocol for determining instrument resolution is prepared as a written standard to allow both comparable quantitative measurements of surface topography and direct comparisons between different instruments. In this paper we assess a range of quantitative methods for determining instrument resolution and determine their relative merits when applied to the specific case of the scanning helium microscope (SHeM). Consequently, we present a preliminary protocol for measuring the resolution in scanning helium microscopy based upon utilizing appropriate test samples with sets of slits of well-defined dimensions to establish the quantitative resolution of any similar instrument.

Managing loneliness: a qualitative study of older people's views.

Engaging with older people who self-identify as lonely may help professionals in mental health and other services understand how they deal with loneliness. The evidence-base for effective interventions to address loneliness is inconclusive. This study aimed to explore how community-dwelling lonely older people in England manage their experiences of loneliness. Twenty eight community-dwelling older people identifying as lonely, based on responses to two loneliness measures (self-report and a standardised instrument), participated in in-depth interviews between 2013 and 2014. Fifteen lived alone. Thematic analysis of transcribed interviews was conducted by a multidisciplinary team including older people.Participants drew on a range of strategies to ameliorate their distress which had been developed over their lives and shaped according to individual coping styles and contexts. Strategies included physical engagement with the world beyond their home, using technologies, planning, and engagement with purpose in an 'outside world', and acceptance, endurance, revealing and hiding, positive attitude and motivation, and distraction within an 'inside world'. Strategies of interests and hobbies, comparative thinking, religion and spirituality and use of alcohol straddled both the inside and outside worlds. Participants conveyed a personal responsibility for managing feelings of loneliness rather than relying on others. This study includes the experiences of those living with loneliness whilst also living with other people. When developing policy and practice responses to loneliness it is important to listen attentively to the views of those who may not be engaging with services designed for 'the lonely' and to consider their own strategies for managing it.

Successful weight loss after bariatric surgery in Appalachian state regardless of food access ranking score.

BACKGROUND: Following bariatric surgery, an explicit dietary regimen is required to facilitate and maintain successful weight loss. Without adequate access to healthy foods, weight maintenance can be hindered. OBJECTIVE: Examine influence degree of food access has on Appalachian bariatric surgery patient weight loss outcomes. SETTING: Appalachian University hospital, United States. METHODS: A retrospective chart review was used to examine the influence of food accessibility on weight loss outcomes in an Appalachian bariatric surgery patient population at a large tertiary hospital in West Virginia between 2013 and 2017. Demographic characteristics, health and family history, and 1-year surgery outcomes were collected. A state-specific food accessibility score was calculated for each patient address using the geographic information system. Patients were assigned a food access ranking score (FARS) between 0 (low food access) and 4 (high food access) based on criteria of quantity, quality, income, and vehicle access. RESULTS: Patients (n = 369) were predominately married (60.5%), white (92.4%), female (77.8%), and underwent laparoscopic Roux-en-Y gastric bypass surgery (75.9%), with a mean age of 45 years. Most patients had low FARS (M = 1.67 ± .73; 72.6%). Nonwhite patients (P = .03) with a preoperative diagnosis of depression (P = .02) or without a family history of obesity (P = .01) were found to be in the lower FARS categories. FARS was not indicative of weight loss post surgery (P > .05). CONCLUSIONS: Food accessibility in West Virginia was not associated with bariatric surgery weight outcomes at 1-year post operation. Lower food access was associated with nonwhite race/ethnicity, diagnosed depression at baseline, and no family history of obesity. Future studies should include more extended follow-up data collection and mixed-method approaches to capture perceptions of food access and its impact on the patients' postoperative journey.

Children's home and school neighbourhood exposure to alcohol marketing: Using wearable camera and GPS data to directly examine the link between retailer availability and visual exposure to marketing.

BACKGROUND AND AIM: Neighbourhood alcohol availability has been associated with alcohol consumption by children, despite children rarely acquiring alcohol from retailers. This study explores one potential reason for this finding, by evaluating the relationships between neighbourhood alcohol availability and children's actual exposure to alcohol marketing. METHOD: Wearable cameras and GPS devices were worn by 167 children (aged 11-13 y) over a four-day period. Image and GPS data were linked and compared to known alcohol availability data. RESULTS: Off-licence retailer availability and ethnicity were positively associated with children's exposure to marketing in both residential and school neighbourhoods. CONCLUSION: Neighbourhood off-licence alcohol retailers are associated with increased childhood exposure to alcohol marketing.

Image formation in the scanning helium microscope.

The scanning helium microscope (SHeM) is a new addition to the array of available microscopies, particularly for delicate materials that may suffer damage under techniques utilising light or charged particles. As with all other microscopies, the specifics of image formation within the instrument are required to gain a full understanding of the produced micrographs. We present work detailing the basics of the subject for the SHeM, including the specific nature of the projection distortions that arise due to the scattering geometry. Extension of these concepts allowed for an iterative ray tracing Monte Carlo model replicating diffuse scattering from a sample surface to be constructed. Comparisons between experimental data and simulations yielded a minimum resolvable step height of (67 ±â€¯5) µm and a minimum resolvable planar angle of (4.3 ±â€¯0.3)° for the instrument in question.

Using Google Earth to Assess Shade for Sun Protection in Urban Recreation Spaces: Methods and Results.

Shade in public spaces can lower the risk of and sun burning and skin cancer. However, existing methods of auditing shade require travel between sites, and sunny weather conditions. This study aimed to evaluate the feasibility of free computer software-Google Earth-for assessing shade in urban open spaces. A shade projection method was developed that uses Google Earth street view and aerial images to estimate shade at solar noon on the summer solstice, irrespective of the date of image capture. Three researchers used the method to separately estimate shade cover over pre-defined activity areas in a sample of 45 New Zealand urban open spaces, including 24 playgrounds, 12 beaches and 9 outdoor pools. Outcome measures included method accuracy (assessed by comparison with a subsample of field observations of 10 of the settings) and inter-rater reliability. Of the 164 activity areas identified in the 45 settings, most (83%) had no shade cover. The method identified most activity areas in playgrounds (85%) and beaches (93%) and was accurate for assessing shade over these areas (predictive values of 100%). Only 8% of activity areas at outdoor pools were identified, due to a lack of street view images. Reliability for shade cover estimates was excellent (intraclass correlation coefficient of 0.97, 95% CI 0.97-0.98). Google Earth appears to be a reasonably accurate and reliable and shade audit tool for playgrounds and beaches. The findings are relevant for programmes focused on supporting the development of healthy urban open spaces.

Kids in space: Measuring children's residential neighborhoods and other destinations using activity space GPS and wearable camera data.

INTRODUCTION: Defining the boundary of children's 'neighborhoods' has important implications for understanding the contextual influences on child health. Additionally, insight into activities that occur outside people's neighborhoods may indicate exposures that place-based studies cannot detect. This study aimed to 1) extend current neighborhood research, using data from wearable cameras and GPS devices that were worn over several days in an urban setting; 2) define the boundary of children's neighborhoods by using leisure time activity space data; and 3) determine the destinations visited by children in their leisure time, outside their neighborhoods. METHOD: One hundred and fourteen children (mean age 12y) from Wellington, New Zealand wore wearable cameras and GPS recorders. Residential Euclidean buffers at incremental distances were paired with GPS data (thereby identifying time spent in different places) to explore alternative definitions of neighborhood boundaries. Children's neighborhood boundary was at 500 m. A newly developed software application was used to identify 'destinations' visited outside the neighborhood by specifying space-time parameters. Image data from wearable cameras were used to determine the type of destination. RESULTS: Children spent over half of their leisure time within 500 m of their homes. Children left their neighborhood predominantly to visit school (for leisure purposes), other residential locations (e.g. to visit friends) and food retail outlets (e.g. convenience stores, fast food outlets). Children spent more time at food retail outlets than at structured sport and in outdoor recreation locations combined. CONCLUSION: Person-centered neighborhood definitions may serve to better represent children's everyday experiences and neighborhood exposures than previous methods based on place-based measures. As schools and other residential locations (friends and family) are important destinations outside the neighborhood, such destinations should be taken into account. The combination of image data and activity space GPS data provides a more robust approach to understanding children's neighborhoods and activity spaces.

Children's everyday exposure to food marketing: an objective analysis using wearable cameras.

BACKGROUND: Over the past three decades the global prevalence of childhood overweight and obesity has increased by 47%. Marketing of energy-dense nutrient-poor foods and beverages contributes to this worldwide increase. Previous research on food marketing to children largely uses self-report, reporting by parents, or third-party observation of children's environments, with the focus mostly on single settings and/or media. This paper reports on innovative research, Kids'Cam, in which children wore cameras to examine the frequency and nature of everyday exposure to food marketing across multiple media and settings. METHODS: Kids'Cam was a cross-sectional study of 168 children (mean age 12.6 years, SD = 0.5) in Wellington, New Zealand. Each child wore a wearable camera on four consecutive days, capturing images automatically every seven seconds. Images were manually coded as either recommended (core) or not recommended (non-core) to be marketed to children by setting, marketing medium, and product category. Images in convenience stores and supermarkets were excluded as marketing examples were considered too numerous to count. RESULTS: On average, children were exposed to non-core food marketing 27.3 times a day (95% CI 24.8, 30.1) across all settings. This was more than twice their average exposure to core food marketing (12.3 per day, 95% CI 8.7, 17.4). Most non-core exposures occurred at home (33%), in public spaces (30%) and at school (19%). Food packaging was the predominant marketing medium (74% and 64% for core and non-core foods) followed by signs (21% and 28% for core and non-core). Sugary drinks, fast food, confectionary and snack foods were the most commonly encountered non-core foods marketed. Rates were calculated using Poisson regression. CONCLUSIONS: Children in this study were frequently exposed, across multiple settings, to marketing of non-core foods not recommended to be marketed to children. The study provides further evidence of the need for urgent action to reduce children's exposure to marketing of unhealthy foods, and suggests the settings and media in which to act. Such action is necessary if the Commission on Ending Childhood Obesity's vision is to be achieved.

Children's exposure to alcohol marketing within supermarkets: An objective analysis using GPS technology and wearable cameras.

BACKGROUND AND AIM: Exposure to alcohol marketing within alcohol retailers has been associated with higher rates of childhood drinking, brand recognition, and marketing recall. This study aimed to objectively measure children's everyday exposure to alcohol marketing within supermarkets. METHOD: Children aged 11-13 (n = 167) each wore a wearable camera and GPS device for four consecutive days. Micro-spatial analyses were used to examine exposures within supermarkets. RESULTS: In alcohol retailing supermarkets (n = 30), children encountered alcohol marketing on 85% of their visits (n = 78). Alcohol marketing was frequently near everyday goods (bread and milk) or entrance/exit. CONCLUSION: Alcohol sales in supermarkets should be banned in order to protect children from alcohol marketing.

A simple counter-flow cooling system for a supersonic free-jet beam source assembly.

A simple design for an inexpensive, cooled, free-jet beam source is described. The source assembly features an integrated cooling system as supplied by a counter-flow of chilled nitrogen, and is composed primarily of off-the-shelf tube fittings. The design facilitates rapid implementation and eases subsequent alignment with respect to any downstream beamline aperture. The source assembly outlined cools the full length of the stagnation volume, offering temperature control down to 100 K and long-term temperature stability better than ±1 K.

Unlocking new contrast in a scanning helium microscope.

Delicate structures (such as biological samples, organic films for polymer electronics and adsorbate layers) suffer degradation under the energetic probes of traditional microscopies. Furthermore, the charged nature of these probes presents difficulties when imaging with electric or magnetic fields, or for insulating materials where the addition of a conductive coating is not desirable. Scanning helium microscopy is able to image such structures completely non-destructively by taking advantage of a neutral helium beam as a chemically, electrically and magnetically inert probe of the sample surface. Here we present scanning helium micrographs demonstrating image contrast arising from a range of mechanisms including, for the first time, chemical contrast observed from a series of metal-semiconductor interfaces. The ability of scanning helium microscopy to distinguish between materials without the risk of damage makes it ideal for investigating a wide range of systems.

Neurobiological mechanisms of repetitive transcranial magnetic stimulation of the dorsolateral prefrontal cortex in depression: a systematic review.

Depression is one of the most prevalent mental illnesses worldwide and a leading cause of disability, especially in the setting of treatment resistance. In recent years, repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising alternative strategy for treatment-resistant depression and its clinical efficacy has been investigated intensively across the world. However, the underlying neurobiological mechanisms of the antidepressant effect of rTMS are still not fully understood. This review aims to systematically synthesize the literature on the neurobiological mechanisms of treatment response to rTMS in patients with depression. Medline (1996-2014), Embase (1980-2014) and PsycINFO (1806-2014) were searched under set terms. Three authors reviewed each article and came to consensus on the inclusion and exclusion criteria. All eligible studies were reviewed, duplicates were removed, and data were extracted individually. Of 1647 articles identified, 66 studies met both inclusion and exclusion criteria. rTMS affects various biological factors that can be measured by current biological techniques. Although a number of studies have explored the neurobiological mechanisms of rTMS, a large variety of rTMS protocols and parameters limits the ability to synthesize these findings into a coherent understanding. However, a convergence of findings suggest that rTMS exerts its therapeutic effects by altering levels of various neurochemicals, electrophysiology as well as blood flow and activity in the brain in a frequency-dependent manner. More research is needed to delineate the neurobiological mechanisms of the antidepressant effect of rTMS. The incorporation of biological assessments into future rTMS clinical trials will help in this regard.

A highly contrasting scanning helium microscope.

We present a scanning helium microscope equipped to make use of the unique contrast mechanisms, surface sensitivity, and zero damage imaging the technique affords. The new design delivers an order of magnitude increase in the available helium signal, yielding a higher contrast and signal-to-noise ratio. These improvements allow the microscope to produce high quality, intuitive images of samples using topological contrast, while setting the stage for investigations into further contrast mechanisms.

Chiari malformations: diagnosis, treatments and failures.

Chiari malformations refer to abnormalities of the hindbrain originally described by the Austrian pathologist Hans Chiari in the early 1890s. These malformations range from herniation of the cerebellar tonsils through the foramen magnum to complete agenesis of the cerebellum. In this review, we review the different classification schemes of Chiari malformations. We discuss the different signs and symptoms that the two most common malformations present with and diagnostic criteria. We next discuss current treatment paradigms, including the new measure of possible in utero surgery to help decrease the incidence of Chiari type II malformations. There is also a small discussion of treatment failures and salvage procedures in these difficult cases. Chiari malformations are a difficult clinical entity to treat. As more is learned about the genetic and environmental factors relating to their characteristics, it will be interesting if we are able to predict which treatments are better suited for different patients. Similarly, with the evolution of in utero techniques especially for Chiari II malformations, it will be interesting to see if the incidence and practice of treating these difficult patients will change.

Morbidity and mortality of live lung donation: results from the RELIVE study.

The Renal and Lung Living Donors Evaluation Study assesses outcomes of live lung (lobectomy) donors. This is a retrospective cohort study at University of Southern California (USC) and Washington University (WASHU) Medical Centers (1993­2006), using medical records to assess morbidity and national databases to ascertain postdonation survival and lung transplantation. Serious complications were defined as those that required significant treatment, were potentially life-threatening or led to prolonged hospitalization. The 369 live lung donors (287 USC, 82 WASHU) were predominantly white, non-Hispanic and male; 72% had a biological relationship to the recipient, and 30% were recipient parents. Serious complications occurred in 18% of donors; 2.2% underwent reoperation and 6.5% had an early rehospitalization. The two centers had significantly different incidences of serious complications (p < 0.001). No deaths occurred and no donors underwent lung transplantation during 4000+ person-years of follow-up (death: minimum 4, maximum 17 years; transplant: minimum 5, maximum 19). Live lung donation remains a potential option for recipients when using deceased donor lungs lacks feasibility. However, the use of two live donors for each recipient and the risk of morbidity associated with live lung donation do not justify this approach when deceased lung donors remain available. Center effects and long-term live donor outcomes require further evaluation.

PD-L1 Expression in Clear Cell Renal Cell Carcinoma: An Analysis of Nephrectomy and Sites of Metastases.

BACKGROUND: Expression of programmed death ligand (PD-L1/B7-H1/CD274) represents a mechanism of immune escape for renal cell carcinoma (RCC) cells. Drugs blocking PD-L1 or its receptor are in clinical development and early data suggests that tumor PD-L1 expression may predict response. PATIENTS AND METHODS: A tissue microarray (TMA) consisting of four biopsy cores from 34 matched pairs of nephrectomy and metastatic sites of clear cell RCC was used to assess PD-L1 expression by quantitative immunofluorescence. Assessment of intra- and inter-tumor heterogeneity and primary and metastatic tumor expression was performed using a method of Automated Quantitative Analysis (AQUA). RESULTS: The median AQUA scores were higher in metastatic than primary specimens (P < 0.0001). The correlation between PD-L1 expression in matched primary and metastatic specimens was weak (R= 0.24). Within a given tumor, variable PD-L1 staining heterogeneity was seen, however the degree of heterogeneity was similar in primary and metastatic sites (P = 0.482). CONCLUSIONS: The weak correlation between PD-L1 expression in primary and metastatic sites for a given patient suggests that expression in nephrectomy specimens cannot be used to select metastatic RCC patients for PD-L1 and PD-1 inhibitors. The intra-tumor heterogeneity seen in both primary and metastatic specimens indicates that a single core biopsy might not be sufficient to determine PD-L1 expression.

Guidelines on the use of extracorporeal photopheresis.

BACKGROUND: After the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma was published in 1983 with its subsequent recognition by the FDA for its refractory forms, the technology has shown significant promise in the treatment of other severe and refractory conditions in a multi-disciplinary setting. Among the major studied conditions are graft versus host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection and inflammatory bowel disease. MATERIALS AND METHODS: In order to provide recognized expert practical guidelines for the use of this technology for all indications the European Dermatology Forum (EDF) proceeded to address these questions in the hands of the recognized experts within and outside the field of dermatology. This was done using the recognized and approved guidelines of EDF for this task. RESULTS AND CONCLUSION: These guidelines provide at present the most comprehensive available expert recommendations for the use of extracorporeal photopheresis based on the available published literature and expert consensus opinion.