Exploring how fire spread mode shapes the composition of pyrogenic carbon from burning forest litter fuels in a combustion wind tunnel.

In this study, solid state 13C nuclear magnetic resonance (NMR) spectroscopy was used to explore the carbon-containing functional groups present in pyrogenic carbon (PyC) produced during different fire spread modes to forest litter fuels from a dry sclerophyll eucalypt forest burnt in a combustion wind tunnel. A replicated experimental study was performed using three different fire spread modes: heading fires (i.e. fires which spread with the wind), flanking fires (i.e. fires which spread perpendicular to the wind) and backing fires (i.e. fires which spread against the wind). In addition to 13C NMR measurements of PyC, detailed fire behaviour measurements were recorded during experiments. Experiments showed that heading fires produced significantly more aryl carbon in ash samples than flanking fires. All other experimental comparisons for burnt fuel samples involving different fire spread modes were statistically insignificant. Principal component analysis (PCA) was used to explore the relationship between 13C NMR functional groups and fire behaviour observations. Results from PCA indicate that maximising the residence time of high temperature combustion and the combustion factor (i.e. the fraction of pre-fire biomass consumed by fire) could be a method for increasing the amount of aryl carbon in PyC. Maximising the amount of aryl carbon could be beneficial for the overall PyC balance from fire, since more recalcitrant carbon (e.g. carbon with a higher aryl carbon content) that is not emitted to the atmosphere has been shown to have longer residence times in environmental media such as soils or sediments.

The Importance of Consistent Global Forest Aboveground Biomass Product Validation.

Several upcoming satellite missions have core science requirements to produce data for accurate forest aboveground biomass mapping. Largely because of these mission datasets, the number of available biomass products is expected to greatly increase over the coming decade. Despite the recognized importance of biomass mapping for a wide range of science, policy and management applications, there remains no community accepted standard for satellite-based biomass map validation. The Committee on Earth Observing Satellites (CEOS) is developing a protocol to fill this need in advance of the next generation of biomass-relevant satellites, and this paper presents a review of biomass validation practices from a CEOS perspective. We outline the wide range of anticipated user requirements for product accuracy assessment and provide recommendations for the validation of biomass products. These recommendations include the collection of new, high-quality in situ data and the use of airborne lidar biomass maps as tools toward transparent multi-resolution validation. Adoption of community-vetted validation standards and practices will facilitate the uptake of the next generation of biomass products.

Orbital lymphoma presenting as an unstable ocular prosthesis: a salutary lesson.

We report the unusual presentation of an extranodal marginal zone B-cell lymphoma presenting as instability of an ocular prosthesis. More commonly, the stability of an ocular prosthesis can be affected by orbital implant migration, sunken superior sulcus, eyelid malformations, shallow inferior fornix, and contracted sockets (Charlton & Weinstein, 1995). Although rare, this case highlights the importance of meticulous examination of the socket, including careful palpation for any potential masses. To our knowledge, instability of an ocular prosthesis in association with orbital lymphoma has not been described previously.

Incorrect interpretation of carbon mass balance biases global vegetation fire emission estimates.

Vegetation fires are a complex phenomenon in the Earth system with many global impacts, including influences on global climate. Estimating carbon emissions from vegetation fires relies on a carbon mass balance technique that has evolved with two different interpretations. Databases of global vegetation fire emissions use an approach based on 'consumed biomass', which is an approximation to the biogeochemically correct 'burnt carbon' approach. Here we show that applying the 'consumed biomass' approach to global emissions from vegetation fires leads to annual overestimates of carbon emitted to the atmosphere by 4.0% or 100 Tg compared with the 'burnt carbon' approach. The required correction is significant and represents ∼9% of the net global forest carbon sink estimated annually. Vegetation fire emission studies should use the 'burnt carbon' approach to quantify and understand the role of this burnt carbon, which is not emitted to the atmosphere, as a sink enriched in carbon.

Retinal break formation following contrecoup trauma: case report.

A previously healthy 38-year-old woman was involved in a road traffic accident resulting in severe commotio retinae. Subsequently extramacular retinal dissolution was noted (not previously described). The patient was treated by closed intraocular microsurgery with a successful anatomical and functional result.

Effect of postoperative mydriatics on the iris.

PURPOSE: To assess the role postoperative mydriatics play after extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (IOL) implantation in causing iris modifications and in controlling inflammation. SETTING: Outpatients Department, Ninewells Hospital, Dundee, Scotland. METHODS: The prospective study comprised 136 patients who had standardized ECCE. Half the patients used a mydriatic for 2 weeks postoperatively. Anterior chamber activity, pain, and eye redness were evaluated at 2 weeks postoperatively; pupil shape, peripheral anterior synechias, IOL position, and iris adhesions, at 6 weeks. RESULTS: Iris-lens adhesions were significantly more common in the group using a mydriatic. There was no difference between the two groups in postoperative inflammation. CONCLUSION: Mydriatics should not be used routinely after ECCE with posterior chamber IOL implantation.

Gender differences in work and well-being: effects of exposure and vulnerability.

Evidence regarding women's differential exposure to job stressors has accumulated; however, there is also evidence that women are more vulnerable to stressors. Using a sample of 994 employed Canadians, a job stress model that evaluates the differential exposure and vulnerability of men and women to job stressors is tested. The analysis considers the direct and moderating effects of occupational self-direction, job demands, and co-worker social support on distress. Results provide support for the conditional effects of job demands. Two dimensions of occupational self-direction, substantive complexity and routinization, interact with one measure of job demands. Although women are exposed to lower substantive complexity and lower job control, the effect of these dimensions of occupational self-direction are similar for men and women, suggesting that differential exposure to job stressors does not account for women's higher distress. Results indicate that, controlling for exposure, marital status, and income, women are more vulnerable to the negative effect of job routinization.

Gender differences in the effect of job stressors on alcohol consumption.

Using a Toronto sample of 994 employed men and women, this analysis considers gender differences and the effect of job stressors on alcohol consumption. Controlling for age, income, marital status, hours of work, and family history of alcohol abuse, results indicate that both male and female respondents in jobs high in substantive complexity consume significant less alcohol than respondents in jobs low in complexity. Two gender differences were found. Job demands have no impact on men's alcohol consumption, but they significantly increase women's drinking. Conversely, job noxiousness has no effect on women's alcohol consumption, but it significantly increases men's consumption. Results are discussed with reference to the public health policy implications of the findings and with reference to the multiple health risks confronting women in stressful jobs.

Use of mobile screening unit for diabetic retinopathy in rural and urban areas.

OBJECTIVES: To compare the effectiveness of a mobile screening unit with a non-mydriatic polaroid camera in detecting diabetic retinopathy in rural and urban areas. To estimate the cost of the service. DESIGN: Prospective data collection over two years of screening for diabetic retinopathy throughout Tayside. SETTING: Tayside region, population 390,000, area 7770 km2. SUBJECTS: 961 patients in rural areas and 1225 in urban areas who presented for screening. MAIN OUTCOME MEASURES: Presence of diabetic retinopathy, need for laser photocoagulation, age, duration of diabetes, and diabetic treatment. RESULTS: Compared with diabetic patients in urban areas, those in rural areas were less likely to attend a hospital based diabetic clinic (46% (442) v 86% (1054), p < 0.001); less likely to be receiving insulin (260 (27%) v 416 (34%), p < 0.001 and also after correction for differences in age distribution); more likely to have advanced (maculopathy or proliferative retinopathy) diabetic retinopathy (13% (122) v 7% (89), p < 0.001); and more likely to require urgent laser photocoagulation for previously unrecognised retinopathy (1.4% (13) v 0.5% (6), p < 0.02). The screening programme cost 10 pounds per patient screened and 1000 pounds per patient requiring laser treatment. CONCLUSION: The mobile diabetic eye screening programme detected a greater prevalence of advanced retinopathy in diabetic patients living in rural areas. Patients in rural areas were also more likely to need urgent laser photocoagulation. Present screening procedures seem to be less effective in rural areas and rural patients may benefit more from mobile screening units than urban patients.

Post-intravitreal anti-VEGF endophthalmitis in the United Kingdom: incidence, features, risk factors, and outcomes.

PURPOSE: To describe the incidence, features, management, and risk factors of post-intravitreal anti-VEGF endophthalmitis (PIAE) in patients undergoing treatment for exudative age-related macular degeneration in the United Kingdom. METHODS: Prospective observational case control study. Forty-seven cases of PIAE were identified through the British Ophthalmological Surveillance Unit from January 2009 to March 2010. Data collected at diagnosis and at 6 months follow-up included patient demographics, intravitreal injection details, pre- and post-injection management, visual acuity, clinical features and management of PIAE, causative organisms, and clinical outcomes. Details were compared with 200 control cases from 10 control centres to identify potential risk factors. RESULTS: Estimated PIAE was 0.025%. Culture-positive PIAE incidence was 0.015%. Mean age of presentation was 78 years. Mean number of intravitreal injections before PIAE was 5. Mean days to presentation was 5 (range 1-39). Positive microbiology culture was found in 59.6%. The majority of causative organisms were Gram positive (92.8%). Significant risk factors were failure to administer topical antibiotics immediately after the injection (P=0.001), blepharitis (P=0.006), subconjunctival anaesthesia (P=0.021), patient squeezing during the injection (P=0.021), and failure to administer topical antibiotics before anti-VEGF injection (P=0.05). DISCUSSION: The incidence of PIAE in the United Kingdom is comparable to other studies at a rate of 0.025%. The most common causative organisms were Gram positive. Measures to minimise the risk of PIAE include treatment of blepharitis before injection, avoidance of subconjunctival anaesthesia, topical antibiotic administration immediately after injection with consideration to administering topical antibiotics before injection.

Estimating forest net primary production under changing climate: adding pests into the equation.

The current approach to modelling pest impacts on forest net primary production (NPP) is to apply a constant modifier. This does not capture the large spatial and temporal variability in pest abundance and activity that can occur, meaning that overestimates or underestimates of pest impacts on forest NPP are likely. Taking a more mechanistic approach that incorporates an understanding of how physiology is influenced by pest attack, enables us to better capture system feedbacks and dynamics, thereby improving the capacity to predict into novel situations such as changing climate, and to account for both changes in pest activity and host responses to the growing environment now and into the future. We reviewed the effects of pests on forest NPP and found a range of responses and physiological mechanisms underlying those responses. Pest outbreaks can clearly be a major perturbation to forest NPP, and it seems likely that the frequency and intensity of pest outbreaks, and the ways in which host species respond to pest damage, will change in the future. We summarized these impacts in the form of a conceptual model at leaf, tree and stand scales, and compared the physiological processes embedded within that framework with the capacity of a representative range of NPP models to capture those processes. We found that some models can encapsulate some of the processes, but no model can comprehensively account for the range of physiological responses to pest attack experienced by trees. This is not surprising, given the paucity of empirical data for most of the world's forests, and that the models were developed primarily for other purposes. We conclude with a list of the key physiological processes and pathways that need to be included in forest growth models in order to adequately capture pest impacts on forest NPP under current and future climate scenarios, the equations that might enable this and the empirical data required to support them.

Awareness of smoking risks and attitudes towards graphic health warning labels on cigarette packs: a cross-cultural study of two populations in Singapore and Scotland.

BACKGROUND: Little is known about the level of awareness of blindness as a smoking-related condition, although the relationship has been well established. AIM: To compare the awareness of smoking risks and the impact of graphic health warning labels on cigarette packs in discouraging smoking among adults in Singapore and Scotland. METHODS: A cross-sectional survey using a structured interview of adults in ophthalmic, general medical, and general surgical outpatient clinics in Singapore and Scotland. RESULTS: One hundred and fifteen out of 163 (70.6%) outpatients in Singapore and 105 out of 112 (93.8%) outpatients in Scotland responded to the study. In both samples, awareness levels for smoking-related diseases such as lung cancer, mouth and throat cancer, heart disease, and stroke were all greater than 85%. These were found to be significantly higher than the level of awareness of blindness as a smoking-related condition (chi (2)-test, P<0.001). Although the awareness of blindness as a smoking-related condition was greater in Singapore (36.5%) than in Scotland (30.5%), this difference was not statistically significant. More than half of the respondents indicated that graphic health warning labels would be effective in discouraging them from smoking. CONCLUSION: Graphic health warning labels reading 'Smoking causes blindness' printed on cigarette packs may be useful in raising public awareness of blindness as a smoking-related condition and discouraging the habit of smoking in Singapore and Scotland.

Atypical retinitis pigmentosa with hypophosphatasia.

Hypophosphatasia is a rare inborn error of metabolism. Ocular signs of hypophosphatasia previously described are blue sclera, band keratopathy, conjunctival calcification, cataract, optic atrophy and the complications of craniostenosis. This paper reports the association of a pigmentary dystrophy similar to rod/cone dystrophy with hypophosphatasia.