Characterisation of a smartphone image sensor response to direct solar 305nm irradiation at high air masses

This research reports the first time the sensitivity, properties and response of a smartphone image sensor that has been used to characterise the photobiologically important direct UVB solar irradiances at 305nm in clear sky conditions at high air masses. Solar images taken from Autumn to Spring were analysed using a custom Python script, written to develop and apply an adaptive threshold to mitigate the effects of both noise and hot-pixel aberrations in the images. The images were taken in an unobstructed area, observing from a solar zenith angle as high as 84° (air mass=9.6) to local solar maximum (up to a solar zenith angle of 23°) to fully develop the calibration model in temperatures that varied from 2°C to 24°C. The mean ozone thickness throughout all observations was 281±18 DU (to 2 standard deviations). A Langley Plot was used to confirm that there were constant atmospheric conditions throughout the observations. The quadratic calibration model developed has a strong correlation between the red colour channel from the smartphone with the Microtops measurements of the direct sun 305nm UV, with a coefficient of determination of 0.998 and very low standard errors. Validation of the model verified the robustness of the method and the model, with an average discrepancy of only 5% between smartphone derived and Microtops observed direct solar irradiances at 305nm. The results demonstrate the effectiveness of using the smartphone image sensor as a means to measure photobiologically important solar UVB radiation. The use of ubiquitous portable technologies, such as smartphones and laptop computers to perform data collection and analysis of solar UVB observations is an example of how scientific investigations can be performed by citizen science based individuals and groups, communities and schools.

Effect of a national urgent care telephone triage service on population perceptions of urgent care provision: controlled before and after study

OBJECTIVE

To measure the effect of an urgent care telephone service NHS 111 on population perceptions of urgent care.

DESIGN

Controlled before and after population survey, using quota sampling to identify 2000 respondents reflective of the age/sex profile of the general population.

SETTING

England. 4 areas where NHS 111 was introduced, and 3 control areas where NHS 111 had yet to be introduced.

PARTICIPANTS

28 071 members of the general population, including 2237 recent users of urgent care.

INTERVENTION

NHS 111 offers advice to members of the general population seeking urgent care, recommending the best service to use or self-management. Policymakers introduced NHS 111 to improve access to urgent care.

OUTCOMES MEASURES

The primary outcome was change in satisfaction with recent urgent care use 9 months after the launch of NHS 111. Secondary outcomes were change in satisfaction with urgent care generally and with the national health service.

RESULTS

The overall response rate was 28% (28 071/100 408). 8% (2237/28 071) had used urgent care in the previous 3 months. Of the 652 recent users of urgent care in the NHS 111 intervention areas, 9% (60/652) reported calling NHS 111 in the 'after' period. There was no evidence that the introduction of NHS 111 was associated with a changed perception of recent urgent care. For example, the percentage rating their experience as excellent remained at 43% (OR 0.97, 95% CI 0.69 to 1.37). Similarly, there was no change in population perceptions of urgent care generally (1.06, 95% CI 0.95 to 1.17) or the NHS (0.94, 95% CI 0.85 to 1.05) following the introduction of NHS 111.

CONCLUSIONS

A new telephone triage service did not improve perceptions of urgent care or the health service. This could be explained by the small amount of NHS 111 activity in a large emergency and urgent care system.

The Three-item ALERT-B Questionnaire Provides a Validated Screening Tool to Detect Chronic Gastrointestinal Symptoms after Pelvic Radiotherapy in Cancer Survivors

AIMS

Although pelvic radiotherapy is an effective treatment for various malignancies, around half of patients develop significant gastrointestinal problems. These symptoms often remain undetected, despite the existence of effective treatments. This study developed and refined a simple screening tool to detect common gastrointestinal symptoms in outpatient clinics. These symptoms have a significant effect on quality of life. This tool will increase detection rates and so enable access to specialist gastroenterologists, which will in turn lead to improved symptom control and quality of life after treatment.

MATERIALS AND METHODS

A literature review and expert consensus meeting identified four items for the ALERT-B (Assessment of Late Effects of RadioTherapy - Bowel) screening tool. ALERT-B was face tested for its usability and acceptability using cognitive interviews with 12 patients experiencing late gastrointestinal symptoms after pelvic radiotherapy. Thematic analysis and probe category were used to analyse interview transcripts. Interview data were presented to a group of experts to agree on the final content and format of the tool. ALERT-B was assessed for reliability and tested for validity against the Gastrointestinal Symptom Rating Scale in a clinical study (EAGLE).

RESULTS

Overall, the tool was found to be acceptable in terms of wording, response format and completion time. Participant-reported experiences, including lifestyle modifications and the psychological effect of the symptoms, led to further modifications of the tool. The refined tool includes three questions covering rectal bleeding, incontinence, nocturnal bowel movements and impact on quality of life, including mood, relationships and socialising. ALERT-B was successfully validated against the Gastrointestinal Symptom Rating Scale in the EAGLE study with the tool shown broadly to be internally consistent (Cronbach's α = 0.61 and all item-subscale correlation [Spearman] coefficients are > 0.6).

CONCLUSION

The ALERT-B screening tool can be used in clinical practice to improve post-treatment supportive care by triggering the clinical assessment of patients suitable for referral to a gastroenterologist.

The Cost of the Gluten-Free Diet: Household Food Expenditures in Families With a Child or Adolescent With Celiac Disease

BACKGROUND: Celiac disease (CD) is a digestive disease that is caused by an immune reaction to the protein gluten. The gluten free diet (GFD) is the only treatment for CD. In 2012, the sale of GF processed foods reached up to $460million in Canada; an increase in 25% since 2008. Despite being the fastest growing food intolerance category in Canada, GFD consumers face challenges from various voluntary GF-labelling schemes and limited retail and food-service product options.

OBJECTIVES: To estimate GF-food expenditure patterns for affected families with children or adolescents with CD to identify the cost burden of following a GFD and compared against non-GFD Canadian families.

DESIGN/METHODS: A pilot study was conducted in families with a child with biopsy proven CD following the GFD (n=15; 10±3 years) and attending a GI/CD clinic. Family Socio-demographics (age of parents, number of children/number of members following GFD in households) and the receipts of food purchases over a one-month period were obtained from parents/caregivers. The cost of GFD was analyzed as “actual food costs on related receipts” and determined as total GFD cost (per household/per child with CD) basis. The result of this study was compared against average incomes and food expenditures of Canadian households as reported by Statistic Canada in 2013.

RESULTS: The mean age of the parents of child with CD was (44±5 years) and the mean number of children in households was 2.0±0.6. The average duration of following GFD was 4±2 years (age at diagnosis 6±2 years). The median income for Canadian family and for family with children with CD was C$ 84,000/year and C$ 100,000/year, respectively. The average food expenditure was C$ 842/month for the average Canadian household with children vs C$ 1105±393/month for comparable Canadian households affected by CD. The amount of money spent on GF packaged foods was C$ 145±100/month. The average food expenditure of GF food and gluten containing food was C$112±72/child/month (+GF) and C$ 29±14/house-hold member/month (-GF), respectively.

CONCLUSION: Total food expenditures in families with a child/adolescent with CD are higher than the Canadian averages. This has implications on economic access and adherence to GFD in children/adolescents with CD. CD and proper dietary adherence to GFD guidelines poses significant economic burdens on affected families. These results and unanswered questions of economic access, affordability and quality of life hold several Canadian policy implications.

Environmental stress in the Gulf of Mexico and its potential impact on public health

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico was the largest maritime oil spill in history resulting in the accumulation of genotoxic substances in the air, soil, and water. This has potential far-reaching health impacts on cleanup field workers and on the populations living in the contaminated coastal areas. We have employed portable airborne particulate matter samplers (SKC Biosampler Impinger) and a genetically engineered bacterial reporter system (umu-ChromoTest from EBPI) to determine levels of genotoxicity of air samples collected from highly contaminated areas of coastal Louisiana including Grand Isle, Port Fourchon, and Elmer's Island in the spring, summer and fall of 2011, 2012, 2013 and 2014. Air samples collected from a non-contaminated area, Sea Rim State Park, Texas, served as a control for background airborne genotoxic particles. In comparison to controls, air samples from the contaminated areas demonstrated highly significant increases in genotoxicity with the highest values registered during the month of July in 2011, 2013, and 2014, in all three locations. This seasonal trend was disrupted in 2012, when the highest genotoxicity values were detected in October, which correlated with hurricane Isaac landfall in late August of 2012, about five weeks before a routine collection of fall air samples. Our data demonstrate: (i) high levels of air genotoxicity in the monitored areas over last four years post DWH oil spill; (ii) airborne particulate genotoxicity peaks in summers and correlates with high temperatures and high humidity; and (iii) this seasonal trend was disrupted by the hurricane Isaac landfall, which further supports the concept of a continuous negative impact of the oil spill in this region.

Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance

MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.

Fetal domoic acid exposure affects lateral amygdala neurons, diminishes social investigation and alters sensory-motor gating

Domoic acid (DA) is an algal neurotoxin that accumulates in marine fish and shellfish. DA can move across the placenta and concentrate in amniotic fluid, which can be swallowed during late gestation. DA also transfers to infants via milk. Preclinical studies to determine effects of developmental DA expose have primarily involved DA exposure during the postnatal period and little is known about late CNS effects following prenatal DA. In the present study, we tested the hypothesis that prenatal exposure of FVB mice to low levels of DA would result in diminished social interaction and sensory motor gating associated with alterations in parvalbumin immunoreactivity in relevant brain regions undergoing development during and following DA exposure. In addition to parvalbumin, we stained with NeuN for a neuronal specific nuclear protein to determine if neuronal loss followed prenatal DA exposure. A single moderate dose of DA administered during gestation produces diminishes social investigation and alters sensorimotor gating, behavioral effects more pronounced in males than females. These behavioral changes were associated with discrete alterations in the parvalbumin-positive subtype of GABAergic neurons in the dentate gyrus and lateral amygdala.

The discovery of a potent series of carboxamide TRPA1 antagonists

Potent and selective carboxamide TRPA1 antagonists were identified by high throughput screening, with efficacy demonstrated in a topical inflammation model.

Is there a relationship between surgical case volume and mortality in congenital heart disease services? A rapid evidence review

OBJECTIVE

To identify and synthesise the evidence on the relationship between surgical volume and patient outcomes for adults and children with congenital heart disease.

DESIGN

Evidence synthesis of interventional and observational studies.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, Cochrane Library and Web of Science (2009-2014) and citation searching, reference lists and recommendations from stakeholders (2003-2014) were used to identify evidence.

STUDY SELECTION

Quantitative observational and interventional studies with information on volume of surgical procedures and patient outcomes were included.

RESULTS

31 of the 34 papers identified (91.2%) included only paediatric patients. 25 (73.5%) investigated the relationship between volume and mortality, 7 (20.6%) mortality and other outcomes and 2 (5.9%) non-mortality outcomes only. 88.2% were from the US, 97% were multicentre studies and all were retrospective observational studies. 20 studies (58.8%) included all congenital heart disease conditions and 14 (41.2%) single conditions or procedures. No UK studies were identified. Most studies showed a relationship between volume and outcome but this relationship was not consistent. The relationship was stronger for single complex conditions or procedures. We found limited evidence about the impact of volume on non-mortality outcomes. A mixed picture emerged revealing a range of factors, in addition to volume, that influence outcome including condition severity, individual centre and surgeon effects and clinical advances over time.

CONCLUSIONS

The heterogeneity of findings from observational studies suggests that, while a relationship between volume and outcome exists, this is unlikely to be a simple, independent and directly causal relationship. The effect of volume on outcome relative to the effect of other, as yet undetermined, health system factors remains a complex and unresolved research question.