Planar laser-induced fluorescence imaging of Si and SiO during pulsed laser ablation of Si

Planar laser induced fluorescence has been used to acquire time sequence images of ground-state, neutral Si and SiO during laser ablation of an Si target in vacuum and in the presence of a background gas at a fluence of 3-4 J/cm^2. The SiO images, taken in air, strongly suggest that the observed SiO is created through reaction of silicon with oxygen at the contact front as the plume expands

Population assessment of future trajectories in coronary heart disease mortality.

Background: Coronary heart disease (CHD) mortality rates have been decreasing in Iceland since the 1980s, largely reflecting improvements in cardiovascular risk factors. The purpose of this study was to predict future CHD mortality in Iceland based on potential risk factor trends. Methods and findings: The previously validated IMPACT model was used to predict changes in CHD mortality between 2010 and 2040 among the projected population of Iceland aged 25–74. Calculations were based on combining: i) data on population numbers and projections (Statistics Iceland), ii) population risk factor levels and projections (Refine Reykjavik study), and iii) effectiveness of specific risk factor reductions (published meta-analyses). Projections for three contrasting scenarios were compared: 1) If the historical risk factor trends of past 30 years were to continue, the declining death rates of past decades would level off, reflecting population ageing. 2) If recent trends in risk factors (past 5 years) continue, this would result in a death rate increasing from 49 to 70 per 100,000. This would reflect a recent plateau in previously falling cholesterol levels and recent rapid increases in obesity and diabetes prevalence. 3) Assuming that in 2040 the entire population enjoys optimal risk factor levels observed in low risk cohorts, this would prevent almost all premature CHD deaths before 2040. Conclusions: The potential increase in CHD deaths with recent trends in risk factor levels is alarming both for Iceland and probably for comparable Western populations. However, our results show considerable room for reducing CHD mortality. Achieving the best case scenario could eradicate premature CHD deaths by 2040. Public health policy interventions based on these predictions may provide a cost effective means of reducing CHD mortality in the future

Analyzing Recent Coronary Heart Disease Mortality Trends in Tunisia between 1997 and 2009.

BACKGROUND: In Tunisia, Cardiovascular Diseases are the leading causes of death (30%), 70% of those are coronary heart disease (CHD) deaths and population studies have demonstrated that major risk factor levels are increasing. OBJECTIVE: To explain recent CHD trends in Tunisia between 1997 and 2009. METHODS: DATA SOURCES: Published and unpublished data were identified by extensive searches, complemented with specifically designed surveys. ANALYSIS: Data were integrated and analyzed using the previously validated IMPACT CHD policy model. Data items included: (i)number of CHD patients in specific groups (including acute coronary syndromes, congestive heart failure and chronic angina)(ii) uptake of specific medical and surgical treatments, and(iii) population trends in major cardiovascular risk factors (smoking, total cholesterol, systolic blood pressure (SBP), body mass index (BMI), diabetes and physical inactivity). RESULTS: CHD mortality rates increased by 11.8% for men and 23.8% for women, resulting in 680 additional CHD deaths in 2009 compared with the 1997 baseline, after adjusting for population change. Almost all (98%) of this rise was explained by risk factor increases, though men and women differed. A large rise in total cholesterol level in men (0.73 mmol/L) generated 440 additional deaths. In women, a fall (-0.43 mmol/L), apparently avoided about 95 deaths. For SBP a rise in men (4 mmHg) generated 270 additional deaths. In women, a 2 mmHg fall avoided 65 deaths. BMI and diabetes increased substantially resulting respectively in 105 and 75 additional deaths. Increased treatment uptake prevented about 450 deaths in 2009. The most important contributions came from secondary prevention following Acute Myocardial Infarction (AMI) (95 fewer deaths), initial AMI treatments (90), antihypertensive medications (80) and unstable angina (75). CONCLUSIONS: Recent trends in CHD mortality mainly reflected increases in major modifiable risk factors, notably SBP and cholesterol, BMI and diabetes. Current prevention strategies are mainly focused on treatments but should become more comprehensive

The TgsGP gene is essential for resistance to human serum in Trypanosoma brucei gambiense

Trypanosoma brucei gambiense causes 97% of all cases of African sleeping sickness, a fatal disease of sub-Saharan Africa. Most species of trypanosome, such as T. b. brucei, are unable to infect humans due to the trypanolytic serum protein apolipoprotein-L1 (APOL1) delivered via two trypanosome lytic factors (TLF-1 and TLF-2). Understanding how T. b. gambiense overcomes these factors and infects humans is of major importance in the fight against this disease. Previous work indicated that a failure to take up TLF-1 in T. b. gambiense contributes to resistance to TLF-1, although another mechanism is required to overcome TLF-2. Here, we have examined a T. b. gambiense specific gene, TgsGP, which had previously been suggested, but not shown, to be involved in serum resistance. We show that TgsGP is essential for resistance to lysis as deletion of TgsGP in T. b. gambiense renders the parasites sensitive to human serum and recombinant APOL1. Deletion of TgsGP in T. b. gambiense modified to uptake TLF-1 showed sensitivity to TLF-1, APOL1 and human serum. Reintroducing TgsGP into knockout parasite lines restored resistance. We conclude that TgsGP is essential for human serum resistance in T. b. gambiense

Explaining the decline in coronary heart disease mortality in Turkey between 1995 and 2008.

BACKGROUND: Coronary heart disease (CHD) mortality rates have been decreasing in Turkey since the early 1990s. Our study aimed to determine how much of the CHD mortality decrease in Turkey between 1995 and 2008 could be attributed to temporal trends in major risk factors and how much to advances in medical and surgical treatments. METHODS: The validated IMPACT CHD mortality model was used to combine and analyse data on uptake and effectiveness of CHD treatments and risk factor trends in Turkey in adults aged 35-84 years between 1995 and 2008.Data sources were identified, searched and appraised on population, mortality and major CHD risk factors for adults those aged 35-84 years. Official statistics, electronic databases, national registers, surveys and published trials were screened from 1995 onwards. RESULTS: Between 1995 and 2008, coronary heart disease mortality rates in Turkey decreased by 34% in men and 28% in women 35 years and over. This resulted in 35,720 fewer deaths in 2008.Approximately 47% of this mortality decrease was attributed to treatments in individuals (including approximately 16% to secondary prevention, 3% angina treatments, 9% to heart failure treatments, 5% to initial treatments of acute myocardial infarction, and 5% to hypertension treatments) and approximately 42% was attributable to population risk factor reductions (notably blood pressure 29%; smoking 27%; and cholesterol 1%). Adverse trends were seen for obesity and diabetes (potentially increasing mortality by approximately 11% and 14% respectively). The model explained almost 90% of the mortality fall. CONCLUSION: Reduction in major cardiovascular risk factors explained approximately 42% and improvements in medical and surgical treatments explained some 47% of the CHD mortality fall. These findings emphasize the complimentary value of primary prevention and evidence-based medical treatments in controlling coronary heart disease

Systematic review of dietary salt reduction policies: Evidence for an effectiveness hierarchy?

Background: Non-communicable disease (NCD) prevention strategies now prioritise four major risk factors: food, tobacco, alcohol and physical activity. Dietary salt intake remains much higher than recommended, increasing blood pressure, cardiovascular disease and stomach cancer. Substantial reductions in salt intake are therefore urgently needed. However, the debate continues about the most effective approaches. To inform future prevention programmes, we systematically reviewed the evidence on the effectiveness of possible salt reduction interventions. We further compared “downstream, agentic” approaches targeting individuals with “upstream, structural” policy-based population strategies. Methods: We searched six electronic databases (CDSR, CRD, MEDLINE, SCI, SCOPUS and the Campbell Library) using a pre-piloted search strategy focussing on the effectiveness of population interventions to reduce salt intake. Retrieved papers were independently screened, appraised and graded for quality by two researchers. To facilitate comparisons between the interventions, the extracted data were categorised using nine stages along the agentic/structural continuum, from “downstream”: dietary counselling (for individuals, worksites or communities), through media campaigns, nutrition labelling, voluntary and mandatory reformulation, to the most “upstream” regulatory and fiscal interventions, and comprehensive strategies involving multiple components. Results: After screening 2,526 candidate papers, 70 were included in this systematic review (49 empirical studies and 21 modelling studies). Some papers described several interventions. Quality was variable. Multi-component strategies involving both upstream and downstream interventions, generally achieved the biggest reductions in salt consumption across an entire population, most notably 4g/day in Finland and Japan, 3g/day in Turkey and 1.3g/day recently in the UK. Mandatory reformulation alone could achieve a reduction of approximately 1.45g/day (three separate studies), followed by voluntary reformulation (-0.8g/day), school interventions (-0.7g/day), short term dietary advice (-0.6g/day) and nutrition labelling (-0.4g/day), but each with a wide range. Tax and community based counselling could, each typically reduce salt intake by 0.3g/day, whilst even smaller population benefits were derived from health education media campaigns (-0.1g/day). Worksite interventions achieved an increase in intake (+0.5g/day), however, with a very wide range. Long term dietary advice could achieve a -2g/day reduction under optimal research trial conditions; however, smaller reductions might be anticipated in unselected individuals. Conclusions: Comprehensive strategies involving multiple components (reformulation, food labelling and media campaigns) and “upstream” population-wide policies such as mandatory reformulation generally appear to achieve larger reductions in population-wide salt consumption than “downstream”, individually focussed interventions. This ‘effectiveness hierarchy’ might deserve greater emphasis in future NCD prevention strategies

Planar laser-induced fluorescence imaging of Si and SiO during pulsed laser ablation of Si

Planar laser induced fluorescence has been used to acquire time sequence images of ground-state, neutral Si and SiO during laser ablation of an Si target in vacuum and in the presence of a background gas at a fluence of 3-4 J/cm^2. The SiO images, taken in air, strongly suggest that the observed SiO is created through reaction of silicon with oxygen at the contact front as the plume expands