389 research outputs found
Field evidence for the influence of weathering on rock erodibility and channel form in bedrock rivers
Erosion processes in bedrock-floored rivers shape channel cross-sectional geometry and the broader landscape. However, the influence of weathering on channel slope and geometry is not well understood. Weathering can produce variation in rock erodibility within channel cross-sections. Recent numerical modeling results suggest that weathering may preferentially weaken rock on channel banks relative to the thalweg, strongly influencing channel form. Here, we present the first quantitative field study of differential weathering across channel cross-sections. We hypothesize that average cross-section erosion rate controls the magnitude of this contrast in weathering between the banks and the thalweg. Erosion rate, in turn, is moderated by the extent to which weathering processes increase bedrock erodibility. We test these hypotheses on tributaries to the Potomac River, Virginia, with inferred erosion rates from similar to 0.1m/kyr to \u3e0.8m/kyr, with higher rates in knickpoints spawned by the migratory Great Falls knickzone. We selected nine channel cross-sections on three tributaries spanning the full range of erosion rates, and at multiple flow heights we measured (1) rock compressive strength using a Schmidt hammer, (2) rock surface roughness using a contour gage combined with automated photograph analysis, and (3) crack density (crack length/area) at three cross-sections on one channel. All cross-sections showed significant (
Proceedings of the Salford Postgraduate Annual Research Conference (SPARC) 2011
These proceedings bring together a selection of papers from the 2011 Salford Postgraduate Annual Research Conference(SPARC). It includes papers from PhD students in the arts and social sciences, business, computing, science and engineering, education, environment, built environment and health sciences. Contributions from Salford researchers are published here alongside papers from students at the Universities of Anglia Ruskin, Birmingham City, Chester,De Montfort, Exeter, Leeds, Liverpool, Liverpool John Moores and Manchester
The effect of agitation speed, enzyme loading and substrate concentration on enzymatic hydrolysis of cellulose from brewer’s spent grain
Brewer’s spent grain components (cellulose,
hemicellulose and lignin) were fractionated in a
two-step chemical pretreatment process using dilute
sulfuric acid and sodium hydroxide solutions. The
cellulose pulp produced was hydrolyzed with a
cellulolytic complex, Celluclast 1.5 L, at 45 ºC to
convert the cellulose into glucose. Several conditions
were examined: agitation speed (100, 150 and
200 rpm), enzyme loading (5, 25 and 45 FPU/g
substrate), and substrate concentration (2, 5 and 8%
w/v), according to a 2 3 full factorial design aiming to
maximize the glucose yield. The obtained results
were interpreted by analysis of variance and response
surface methodology. The optimal conditions for
enzymatic hydrolysis of brewer’s spent grain were
identified as 100 rpm, 45 FPU/g and 2% w/v substrate.
Under these conditions, a glucose yield of
93.1% and a cellulose conversion (into glucose and
cellobiose) of 99.4% was achieved. The easiness of
glucose release from BSG makes this substrate a raw material with great potential to be used in bioconversion
processes.Coordenação de Aperfeiçoamento de Pessoal de Nível
Superior (CAPES)Fundação de Amparo
à Pesquisa do Estado de São Paulo), Brazil. Novozymes ( FAPESP )Conselho Nacional de Desenvolvimento
Científico e Tecnológico (CNPq
Image perception and interpretation of abnormalities; can we believe our eyes? Can we do something about it?
The radiologist’s visual impression of images is transmitted, via non-visual means (the report), to the clinician. There are several complex steps from the perception of the images by the radiologist to the understanding of the impression by the clinician. With a process as complex as this, it is no wonder that errors in perception, cognition, interpretation, transmission and understanding are very common. This paper reviews the processes of perception and error generation and possible strategies for minimising them
Antiepileptic drugs’ tolerability and safety – a systematic review and meta-analysis of adverse effects in dogs
<p>Various anti-epileptic drugs (AEDs) are used for the management of idiopathic epilepsy (IE) in dogs. Their safety profile is an important consideration for regulatory bodies, owners and prescribing clinicians. However, information on their adverse effects still remains limited with most of it derived from non-blinded non-randomized uncontrolled trials and case reports.</p><p><span>This poster won third place, which was presented at the Veterinary Evidence Today conference, Edinburgh November 1-3, 2016. </span></p><br /> <img src="https://www.veterinaryevidence.org/rcvskmod/icons/oa-icon.jpg" alt="Open Access" /
Development and evaluation of a web-based breast cancer cultural competency course for primary healthcare providers
<p>Abstract</p> <p>Background</p> <p>To develop and evaluate a continuing medical education (CME) course aimed at improving healthcare provider knowledge about breast cancer health disparities and the importance of cross-cultural communication in provider-patient interactions about breast cancer screening.</p> <p>Methods</p> <p>An interactive web-based CME course was developed and contained information about breast cancer disparities, the role of culture in healthcare decision making, and demonstrated a model of cross-cultural communication. A single group pre-/post-test design was used to assess knowledge changes. Data on user satisfaction was also collected.</p> <p>Results</p> <p>In all, 132 participants registered for the CME with 103 completing both assessments. Differences between pre-/post-test show a significant increase in knowledge (70% vs. 94%; p < .001). Ninety-five percent of participants agreed that the web based training was an appropriate tool to train healthcare providers about cultural competency and health disparities.</p> <p>Conclusion</p> <p>There was an overall high level of satisfaction among all users. Users felt that learning objectives were met and the web-based format was appropriate and easy to use and suggests that web-based CME formats are an appropriate tool to teach cultural competency skills. However, more information is needed to understand how the CME impacted practice behaviors.</p
Humoral immune response and delayed type hypersensitivity to influenza vaccine in patients with diabetes mellitus
The antibody response and delayed type hypersensitivity reaction to commercially available trivalent influenza vaccine in 159 patients with diabetes mellitus was compared with response and reaction in 28 healthy volunteers. A correction for prevaccination titres was made. No differences were found between diabetic patients and control subjects with respect to antibody response to the three vaccine strains as measured by the difference between geometric mean titres of post- and prevaccination sera. In Type 1 (insulin-dependent) diabetic patients the incidence of non-responders to two vaccine components was significantly increased (p less than 0.05). The delayed type hypersensitivity reaction to influenza antigen was significantly decreased in patients with high concentrations of glycosylated haemoglobin (p less than 0.01). These findings suggest a role for impaired immune response in the increased influenza morbidity and mortality in patients with diabetes mellitus. Implications for therapy and vaccination strategy are discussed
Differences between patients' and clinicians' report of sleep disturbance: a field study in mental health care in Norway
<p>Abstract</p> <p>Background</p> <p>The aims of the study was to assess the prevalence of diagnosed insomnia and the agreement between patient- and clinician-reported sleep disturbance and use of prescribed hypnotic medication in patients in treatment for mental disorders.</p> <p>Methods</p> <p>We used three cross-sectional, multicenter data-sets from 2002, 2005, and 2008. Data-set 1 included diagnostic codes from 93% of all patients receiving treatment in mental health care in Norway (<it>N </it>= 40261). Data-sets 2 (<it>N </it>= 1065) and 3 (<it>N </it>= 1181) included diagnostic codes, patient- and clinician-reported sleep disturbance, and use of prescribed hypnotic medication from patients in 8 mental health care centers covering 10% of the Norwegian population.</p> <p>Results</p> <p>34 patients in data-set 1 and none in data-sets 2 and 3 had a diagnosis of insomnia as a primary or comorbid diagnosis. In data-sets 2 and 3, 42% and 40% of the patients reported sleep disturbance, whereas 24% and 13% had clinician-reported sleep disturbance, and 7% and 9% used hypnotics. Patients and clinicians agreed in 29% and 15% of the cases where the patient or the clinician or both had reported sleep disturbance. Positive predictive value (PPV) of clinicians' evaluations of patient sleep disturbance was 62% and 53%. When the patient reported sleep disturbance as one of their most prominent problems PPV was 36% and 37%. Of the patients who received hypnotic medication, 23% and 29% had neither patient nor clinician-rated sleep disturbance.</p> <p>Conclusion</p> <p>When patients meet the criteria for a mental disorder, insomnia is almost never diagnosed, and sleep disturbance is imprecisely recognized relative to the patients' experience of sleep disturbance.</p
Time spent on New Songs: Word-of-Mouth and Price Effects on Teenager Consumption
URL des Documents de travail : http://centredeconomiesorbonne.univ-paris1.fr/documents-de-travail/Documents de travail du Centre d'Economie de la Sorbonne 2015.27 - ISSN : 1955-611XThe stardom system characterizes creative industries: the demand and revenues are concentrated on a few bestselling books, movies or music. In this paper, we study the demand structure between bestsellers and new artists' productions in the music industry. We set up an experiment where participants face real choices situations. We crate three treatments to isolate the effect of information and incentives on diversity. In a first treatment, music is consumed for free without information. In a second one, subjects receive a prior information on others' evaluation of songs to study the effect of word-of-mouth. Finally, in a third one, a real market is introduced and music is bought. Significant evidence shows that word-of-mouth lowers diversity, while price incentives tend to lift it. In both treatments, subjects also react to the information or incentives nature
The impact of regional and neighbourhood deprivation on physical health in Germany: a multilevel study
Voigtländer S, Berger U, Razum O. The impact of regional and neighbourhood deprivation on physical health in Germany: a multilevel study. BMC Public Health. 2010;10(1): 403.Background There is increasing evidence that individual health is at least partly determined by neighbourhood and regional factors. Mechanisms, however, remain poorly understood, and evidence from Germany is scant. This study explores whether regional as well as neighbourhood deprivation are associated with physical health and to what extent this association can be explained by specific neighbourhood exposures. Methods Using 2004 data from the German Socio-Economic Panel Study (SOEP) merged with regional and neighbourhood characteristics, we fitted multilevel linear regression models with subjective physical health, as measured by the SF-12, as the dependent variable. The models include regional and neighbourhood proxies of deprivation (i.e. regional unemployment quota, average purchasing power of the street section) as well as specific neighbourhood exposures (i.e. perceived air pollution). Individual characteristics including socioeconomic status and health behaviour have been controlled for. Results This study finds a significant association between area deprivation and physical health which is independent of compositional factors and consistent across different spatial scales. Furthermore the association between neighbourhood deprivation and physical health can be partly explained by specific features of the neighbourhood environment. Among these perceived air pollution shows the strongest association with physical health (-2.4 points for very strong and -1.5 points for strong disturbance by air pollution, standard error (SE) = 0.8 and 0.4, respectively). Beta coefficients for perceived air pollution, perceived noise and the perceived distance to recreational resources do not diminish when including individual health behaviour in the models. Conclusions This study highlights the difference regional and in particular neighbourhood deprivation make to the physical health of individuals in Germany. The results support the argument that specific neighbourhood exposures serve as an intermediary step between deprivation and health. As people with a low socioeconomic status were more likely to be exposed to unfavourable neighbourhood characteristics these conditions plausibly contribute towards generating health inequalities
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