Evaluating LANDSAT-4 MSS and TM data

Interband line pixel misregistrations were determined for the four MSS bands of the Mistassini, Ontario scene and multitemporal registration of LANDSAT-4 products were tested for two different geocoded scenes. Line and pixel misregistrations are tabulated as determined by the manual ground control points and the digital band to band correlation techniques. A method was developed for determining the spectral information content of TM images for forestry applications

Microbiology and atmospheric processes: Biological, physical and chemical characterization of aerosol particles

The interest in bioaerosols has traditionally been linked to health hazards for humans, animals and plants. However, several components of bioaerosols exhibit physical properties of great significance for cloud processes, such as ice nucleation and cloud condensation. To gain a better understanding of their influence on climate, it is therefore important to determine the composition, concentration, seasonal fluctuation, regional diversity and evolution of bioaerosols. In this paper, we will review briefly the existing techniques for detection, quantification, physical and chemical analysis of biological particles, attempting to bridge physical, chemical and biological methods for analysis of biological particles and integrate them with aerosol sampling techniques. We will also explore some emerging spectroscopy techniques for bulk and single-particle analysis that have potential for in-situ physical and chemical analysis. Lastly, we will outline open questions and further desired capabilities (e. g., in-situ, sensitive, both broad and selective, on-line, time-resolved, rapid, versatile, cost-effective techniques) required prior to comprehensive understanding of chemical and physical characterization of bioaerosols

Ice-nucleation negative fluorescent pseudomonads isolated from Hebridean cloud and rain water produce biosurfactants

International audienceMicroorganisms were discovered in clouds over 100 years ago but information on bacterial community structure and function is limited. Clouds may not only be a niche within which bacteria could thrive but they might also influence dynamic processes using ice nucleating and cloud condensing abilities. Cloud and rain samples were collected from two mountains in the Outer Hebrides, NW Scotland, UK. Community composition was determined using a combination of amplified 16S ribosomal DNA restriction analysis and sequencing. 256 clones yielded 100 operational taxonomic units (OTUs) of which half were related to bacteria from terrestrial psychrophilic environments. Cloud samples were dominated by a mixture of fluorescent Pseudomonas spp., some of which have been reported to be ice nucleators. It was therefore possible that these bacteria were using the ice nucleation (IN) gene to trigger the Bergeron-Findeisen process of raindrop formation as a mechanism for dispersal. In this study the IN gene was not detected in any of the isolates using both polymerase chain reaction (PCR) and differential scanning calorimetry (DSC). Instead 55% of the total isolates from both cloud and rain samples displayed significant biosurfactant activity when analyzed using the drop-collapse technique. All were characterised as fluorescent pseudomonads. Surfactants have been found to be very important in lowering atmospheric critical supersaturations required for the activation of aerosols into cloud condensation nuclei (CCN). It is also known that surfactants influence cloud droplet size and increase cloud lifetime and albedo. Some bacteria are known to act as CCN and so it is conceivable that these fluorescent pseudomonads are using surfactants to facilitate their activation from aerosols into CCN. This would allow water scavenging, countering desiccation, and assist in their widespread dispersal

Fluorescent Excitation of Spectral Lines in Planetary Nebulae

Fluorescent excitation of spectral lines is demonstrated as a function of temperature-luminosity and the distance of the emitting region from the central stars of planetary nebulae. The electron densities and temperatures are determined, and the method is exemplified through a detailed analysis of spectral observations of a high excitation PN, NGC 6741, observed by Hyung and Aller(1997). Fluorescence should also be important in the determination of element abundances. It is suggested that the method could be generally applied to determine or constrain the luminosity and the region of spectral emission in other intensively radiative sources such as novae, supernovae, and active galactic nuclei.Comment: 5 pages, 4 figures (fig.4 in color), ApJ (in press

Impact of adult weight management interventions on mental health: a systematic review and meta-analysis protocol

Introduction: The effects of interventions targeting weight loss on physical health are well described, yet the evidence for mental health is less clear. It is essential to better understand the impact of weight management interventions on mental health to optimise care and minimise risk of harm. We will assess the effect of behavioural weight management interventions on mental health in adults with overweight and obesity. Methods and analysis: The systematic review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. We will include behavioural weight management interventions with a diet and/or physical activity component focusing on weight loss for adults with a body mass index ≥25 kg/m2. Randomised controlled trials (RCTs) and cluster RCTs will be the only eligible study designs. Outcomes of interest will be related to mental health. The following databases were searched from inception to 07 May 2019: MEDLINE, Embase, Cochrane database (CENTRAL), PsycINFO, ASSIA, AMED and CINAHL. The search strategy was based on four concepts: (1) adults, defined as ≥18 years, with overweight/obesity, defined as BMI ≥25kg/m², (2) weight management interventions, (3) mental health outcomes and (4) study design. The search was restricted to English-language published papers, with no other restrictions applied. Two stage screening for eligibility will be completed by two independent reviewers, with two independent reviewers completing data extraction and risk of bias assessment. Data permitting, a random-effects meta-analysis of outcomes, subgroup analyses and meta-regression will be conducted. If not appropriate, narrative synthesis and ‘levels of evidence’ assessment will be completed. Ethics and dissemination: Ethical approval is not required as primary data will not be collected. The completed systematic review will be disseminated in a peer-reviewed journal, at conferences and contribute towards the lead author’s PhD thesis. PROSPERO registration number: CRD42019131659

Preventing type 2 diabetes:A research agenda for behavioural science

Aims The aim of this narrative review was to identify important knowledge gaps in behavioural science relating to type 2 diabetes prevention, to inform future research in the field. Methods Seven researchers who have published behaviour science research applied to type 2 diabetes prevention independently identified several important gaps in knowledge. They met to discuss these and to generate recommendations to advance research in behavioural science of type 2 diabetes prevention. Results A total of 21 overlapping recommendations for a research agenda were identified. These covered issues within the following broad categories: (a) evidencing the impact of whole population approaches to type 2 diabetes prevention, (b) understanding the utility of disease-specific approaches to type 2 diabetes prevention such as Diabetes Prevention Programmes (DPPs) compared to generic weight loss programmes, (c) identifying how best to increase reach and engagement of DPPs, whilst avoiding exacerbating inequalities, (d) the need to understand mechanism of DPPs, (e) the need to understand how to increase maintenance of changes as part of or following DPPs, (f) the need to assess the feasibility and effectiveness of alternative approaches to the typical self-regulation approaches that are most commonly used, and (g) the need to address emotional aspects of DPPs, to promote effectiveness and avoid harms. Conclusions There is a clear role for behavioural science in informing interventions to prevent people from developing type 2 diabetes, based on strong evidence of reach, effectiveness and cost-effectiveness. This review identifies key priorities for research needed to improve existing interventions

Routine nasogastric suction may be unnecessary after a pancreatic resection

AbstractBackgroundMost surgeons routinely place a nasogastric tube at the time of a pancreatic resection. The goal of the present study was to evaluate the outcome when a pancreatic resection is performed without routine post-operative nasogastric suction.MethodsOne hundred consecutive patients underwent a pancreatic resection (64a pancreaticoduodenectomy, 98% pylorus sparing and 36a distal pancreatectomy). In the first cohort (50 patients), a nasogastric tube was routinely placed at the time of surgery and in the second cohort (50 patients) the nasogastric was removed in the operating room. Outcomes for these two cohorts were recorded in a prospective database and compared using the χ2 or Fisher's exact test and Wilcoxon's rank-sum test.ResultsDemographical, surgical and pathological details were similar between the two cohorts. A post-operative complication occurred in 22 (44%) in each group (P= 1.000). There were no statistically significant differences in the frequency or severity of complications, or length of stay between groups. The spectrum of complications experienced by the two cohorts was similar including complications that could potentially be related to the use of nasogastric suction such as delayed gastric emptying, anastomotic leak, wound dehiscence and pneumonia. There was no difference between the two groups in the number of patients who required post-operative nasogastric tube placement (or replacement) [2 (4%) vs. 4 (8%), P= 0.678].ConclusionIt may be safe to place a nasogastric tube post-operatively in a minority of patients after a pancreatic resection and spare the majority the discomfort associated with routine post-operative nasogastric suction

Modification of cardiovascular disease risk by health behaviour change following type 2 diabetes diagnosis

Funder: National Health Service R&DAbstract: Aims: Among adults with type 2 diabetes (T2D), unhealthy behaviours are associated with increased risk of cardiovascular disease (CVD) events. To date, little research has considered whether healthy changes in behaviours following T2D diagnosis reduce CVD risk. Methods: A cohort of 867 adults with screen‐detected T2D, participating in the Anglo‐Danish‐Dutch Study of Intensive Treatment in People with Screen‐Detected Diabetes in Primary Care (ADDITION)‐Cambridge trial, were followed for 10 years for incidence of CVD events. Diet, alcohol consumption, moderate/vigorous physical activity and smoking were assessed by questionnaire at the time of T2D screening and 1 year later. We estimated associations between health behaviours and CVD using Cox regression. We assessed modification of the associations by behaviour change in the year following T2D diagnosis. Results: Smoking [hazard ratio (HR): 1.73 (95% CI: 1.04, 2.87)] and high fat intake [HR: 1.70 (95% CI: 1.02, 2.85)] were associated with a higher hazard of CVD, while high plasma vitamin C [HR: 0.44 (95% CI: 0.22, 0.87)] and high fibre intake [HR: 0.60 (95% CI: 0.36, 0.99)] were associated with a lower hazard of CVD. Reduction in fat intake following T2D diagnosis modified associations with CVD. In particular, among those with the highest fat intake, decreasing intake attenuated the association with CVD [HR: 0.75 (95% CI: 0.36, 1.56)]. Conclusion: Following T2D diagnosis, decreasing fat intake was associated with lower long‐term CVD risk. This evidence may raise concerns about low‐carbohydrate, high‐fat diets to achieve weight loss following T2D diagnosis. Further research considering the sources of fat is needed to inform dietary recommendations. Trial registration: This trial is registered as ISRCTN86769081. Retrospectively registered on 15 December 2006