2,754 research outputs found

    Smoking and Risk Taking in Recreational SCUBA Divers

    Get PDF
    SCUBA diving is inherently dangerous. Anecdotal reports suggest that risks may be exacerbated by diver behaviour, particularly tobacco smoking. This thesis reports findings from an internet survey of tobacco use, health and attitudes to risk taking conducted amongst UK members of the Professional Association of Diving Instructors in 2006. The main aims of the study were to assess smoking prevalence and factors associated with tobacco use compared to the UK population and to explore the health impact of smoking on divers, to determine the need for prevention measures in this group. After adjusting for socio-demographic factors, divers’ cigarette smoking prevalence (p<0.001) and consumption (p<0.001) were found to be lower than the UK population, although non-cigarette smoking prevalence was higher (p<0.001). Everyday risk taking scores were significantly associated with cigar or pipe use (p = 0.037) and higher cigarette consumption (p = 0.046) and dependence (p = 0.011) in current smokers. Divers with a professional recreational diving qualification who currently smoked had higher cigarette consumption (p = 0.001) and dependence (p = 0.001) compared with their non-professionally qualified peers. Recreational SCUBA divers were less likely to report poor general health than the UK population, but current cigarette smoking was significantly associated with poorer self-assessed health in divers (p = 0.006) after controlling for socio-demographic factors. After adjustment for confounding variables, current cigarette smoking was significantly associated with the occurrence of panic attacks (p = 0.014), which was significantly associated with lung problems (p = 0.016), and cigarette consumption was significantly associated with the frequency of diving-related illness (p = 0.037). In conclusion, although cigarette smoking prevalence and daily cigarette consumption were significantly lower in divers compared with the UK population, both were found to be associated with poorer health in important ways

    Challenges of modeling depth-integrated marine primary productivity over multiple decades: A case study at BATS and HOT

    Get PDF
    The performance of 36 models (22 ocean color models and 14 biogeochemical ocean circulation models (BOGCMs)) that estimate depth-integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ C-14 data at the Bermuda Atlantic Time series Study (BATS) and the Hawaii Ocean Time series (HOT) over nearly two decades. Specifically, skill was assessed based on the models\u27 ability to estimate the observed mean, variability, and trends of NPP. At both sites, more than 90% of the models underestimated mean NPP, with the average bias of the BOGCMs being nearly twice that of the ocean color models. However, the difference in overall skill between the best BOGCM and the best ocean color model at each site was not significant. Between 1989 and 2007, in situ NPP at BATS and HOT increased by an average of nearly 2% per year and was positively correlated to the North Pacific Gyre Oscillation index. The majority of ocean color models produced in situ NPP trends that were closer to the observed trends when chlorophyll-alpha was derived from high-performance liquid chromatography (HPLC), rather than fluorometric or SeaWiFS data. However, this was a function of time such that average trend magnitude was more accurately estimated over longer time periods. Among BOGCMs, only two individual models successfully produced an increasing NPP trend (one model at each site). We caution against the use of models to assess multiannual changes in NPP over short time periods. Ocean color model estimates of NPP trends could improve if more high quality HPLC chlorophyll-alpha time series were available

    The Process " Pbar P -> E- E+ " with Polarized Initial Particles and Proton Form Factors in Time-Like Region

    Full text link
    The discussion on the asymptotical behaviour of the form factors in the space-like and time-like regions have been corrected and clarified. Fig.3 has been replaced by an improved analysis of the data.Comment: DFTT 13/93. LaTeX file, 11 pages + 3 figures (included

    Efficacy of temsirolimus in metastatic chromophobe renal cell carcinoma

    Get PDF
    &lt;p&gt;Background: Renal cell carcinoma (RCC) is a histopathologically and molecularly heterogeneous disease with the chromophobe subtype (chRCC) accounting for approximately 5% of all cases. The median overall survival of advanced RCC has improved significantly since the advent of tyrosine kinase inhibitors and mammalian target of rapamycin (mTOR) inhibitors. However, high-quality evidence for the use of new generation tyrosine kinase inhibitors in patients with advanced chRCC is lacking. Few published case reports have highlighted the use of temsirolimus in chRCC.&lt;/p&gt; &lt;p&gt;Case presentation: Here, we report the case of a 36-year-old Caucasian woman with metastatic chRCC with predominantly skeletal metastases who was refractory to sunitinib who demonstrated a durable clinical response to temsirolimus lasting 20 months. We review the available evidence pertaining to the use of new generation molecularly targeted agents, in particular mTOR inhibitors in chRCC and discuss their emerging role in the management of this disease which would aid the oncologists faced with the challenge of treating this rare type of RCC.&lt;/p&gt; &lt;p&gt;Conclusion: Conducting randomised clinical trials in this rarer sub-group of patients would be challenging and our case report and the evidence reviewed would guide the physicians to make informed decision regarding the management of these patients.&lt;/p&gt

    Beyond the culture effect on credibility perception on microblogs

    Get PDF
    We investigated the credibility perception of tweet readers from the USA and by readers from eight Arabic countries; our aim was to understand if credibility was affected by country and/or by culture. Results from a crowd-sourcing experiment, showed a wide variety of factors affected credibility perception, including a tweet author&#039;s gender, profile image, username style, location, and social network overlap with the reader. We found that culture determines readers&#039; credibility perception, but country has no effect. We discuss the implications of our findings for user interface design and social media systems

    Femtosecond nonlinear ultrasonics in gold probed with ultrashort surface plasmons

    Get PDF
    Fundamental interactions induced by lattice vibrations on ultrafast time scales become increasingly important for modern nanoscience and technology. Experimental access to the physical properties of acoustic phonons in the THz frequency range and over the entire Brillouin zone is crucial for understanding electric and thermal transport in solids and their compounds. Here, we report on the generation and nonlinear propagation of giant (1 percent) acoustic strain pulses in hybrid gold/cobalt bilayer structures probed with ultrafast surface plasmon interferometry. This new technique allows for unambiguous characterization of arbitrary ultrafast acoustic transients. The giant acoustic pulses experience substantial nonlinear reshaping already after a propagation distance of 100 nm in a crystalline gold layer. Excellent agreement with the Korteveg-de Vries model points to future quantitative nonlinear femtosecond THz-ultrasonics at the nano-scale in metals at room temperature

    Investigation of attentional bias in obsessive compulsive disorder with and without depression in visual search

    Get PDF
    Copyright: © 2013 Morein-Zamir et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedWhether Obsessive Compulsive Disorder (OCD) is associated with an increased attentional bias to emotive stimuli remains controversial. Additionally, it is unclear whether comorbid depression modulates abnormal emotional processing in OCD. This study examined attentional bias to OC-relevant scenes using a visual search task. Controls, non-depressed and depressed OCD patients searched for their personally selected positive images amongst their negative distractors, and vice versa. Whilst the OCD groups were slower than healthy individuals in rating the images, there were no group differences in the magnitude of negative bias to concern-related scenes. A second experiment employing a common set of images replicated the results on an additional sample of OCD patients. Although there was a larger bias to negative OC-related images without pre-exposure overall, no group differences in attentional bias were observed. However, OCD patients subsequently rated the images more slowly and more negatively, again suggesting post-attentional processing abnormalities. The results argue against a robust attentional bias in OCD patients, regardless of their depression status and speak to generalized difficulties disengaging from negative valence stimuli. Rather, post-attentional processing abnormalities may account for differences in emotional processing in OCD.Peer reviewedFinal Published versio
    corecore