1,016 research outputs found
Physical conditions in the primitive solar nebula
Physical conditions for model of primitive solar nebul
A syndrome of altered cardiovascular, craniofacial, neurocognitive and skeletal development caused by mutations in TGFBR1 or TGFBR2
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Fused Traditional and Geometric Morphometrics Demonstrate Pinniped Whisker Diversity
Vibrissae (whiskers) are important components of the mammalian tactile sensory system, and primarily function as detectors of vibrotactile information from the environment. Pinnipeds possess the largest vibrissae among mammals and their vibrissal hair shafts demonstrate a diversity of shapes. The vibrissae of most phocid seals exhibit a beaded morphology with repeating sequences of crests and troughs along their length. However, there are few detailed analyses of pinniped vibrissal morphology, and these are limited to a few species. Therefore, we comparatively characterized differences in vibrissal hair shaft morphologies among phocid species with a beaded profile, phocid species with a smooth profile, and otariids with a smooth profile using traditional and geometric morphometric methods. Traditional morphometric measurements (peak-to-peak distance, crest width, trough width and total length) were collected using digital photographs. Elliptic Fourier analysis (geometric morphometrics) was used to quantify the outlines of whole vibrissae. The traditional and geometric morphometric datasets were subsequently combined by mathematically scaling each to true rank, followed by a single eigendecomposition. Quadratic discriminant function analysis demonstrated that 79.3, 97.8 and 100% of individuals could be correctly classified to their species based on vibrissal shape variables in the traditional, geometric and combined morphometric analyses, respectively. Phocids with beaded vibrissae, phocids with smooth vibrissae, and otariids each occupied distinct morphospace in the geometric morphometric and combined data analyses. Otariids split into two groups in the geometric morphometric analysis and gray seals appeared intermediate between beaded- and smooth-whiskered species in the traditional and combined analyses. Vibrissal hair shafts modulate the transduction of environmental stimuli to the mechanoreceptors in the follicle-sinus complex (F-SC), which results in vibrotactile reception, but it is currently unclear how the diversity of shapes affects environmental signal modulation
Primary graft failure associated with epithelial downgrowth: a case report
BACKGROUND: Epithelial downgrowth is a rare complication of ocular surgery. While the features of epithelial downgrowth following corneal transplantation are well described, its association with primary graft failure has only been reported once previously. We report a case of primary corneal graft failure (PGF) associated with retrocorneal epithelial cell ingrowth. CASE PRESENTATION: A 59 year-old male underwent an uncomplicated penetrating keratoplasty for Fuchs' corneal dystrophy. The patient developed PGF, and a second transplant was performed 5 weeks after the initial surgery. The initial host corneal button and the failed corneal graft were examined with light microscopy. Histopathologic examination of the excised corneal button demonstrated multilaminar epithelial cells on the posterior corneal surface and absence of endothelial cells. DNA extraction and polymerase chain reaction (PCR) for herpes simplex virus (HSV) DNA was performed on the failed corneal graft. Polymerase chain reaction performed on the failed corneal graft was negative for HSV DNA, which has been implicated in selected cases of PGF. Three years following repeat penetrating keratoplasty, there was no evidence of recurrent epithelial ingrowth. CONCLUSION: This is only the second report of PGF associated with epithelialization of the posterior corneal button, which most likely developed subsequent to, instead of causing, the diffuse endothelial cell loss and primary graft failure
Understanding communication networks in the emergency department
<p>Abstract</p> <p>Background</p> <p>Emergency departments (EDs) are high pressure health care settings involving complex interactions between staff members in providing and organising patient care. Without good communication and cooperation amongst members of the ED team, quality of care is at risk. This study examined the problem-solving, medication advice-seeking and socialising networks of staff working in an Australian hospital ED.</p> <p>Methods</p> <p>A social network survey (Response Rate = 94%) was administered to all ED staff (n = 109) including doctors, nurses, allied health professionals, administrative staff and ward assistants. Analysis of the network characteristics was carried out by applying measures of density (the extent participants are concentrated), connectedness (how related they are), isolates (how segregated), degree centrality (who has most connections measured in two ways, in-degree, the number of ties directed to an individual and out-degree, the number of ties directed from an individual), betweenness centrality (who is important or powerful), degree of separation (how many ties lie between people) and reciprocity (how bi-directional are interactions).</p> <p>Results</p> <p>In all three networks, individuals were more closely connected to colleagues from within their respective professional groups. The problem-solving network was the most densely connected network, followed by the medication advice network, and the loosely connected socialising network. ED staff relied on each other for help to solve work-related problems, but some senior doctors, some junior doctors and a senior nurse were important sources of medication advice for their ED colleagues.</p> <p>Conclusions</p> <p>Network analyses provide useful ways to assess social structures in clinical settings by allowing us to understand how ED staff relate within their social and professional structures. This can provide insights of potential benefit to ED staff, their leaders, policymakers and researchers.</p
The effects of adding zoledronic acid to neoadjuvant chemotherapy on tumour response: exploratory evidence for direct anti-tumour activity in breast cancer
Background: Pre-clinical studies have demonstrated synergistic anti-tumour effects of chemotherapy (CT) and zoledronic acid (ZOL). Within the AZURE trial, designed to determine whether the addition of ZOL to neoadjuvant therapy improves disease outcomes, a subgroup received neoadjuvant CT. We report a retrospective evaluation comparing pathological response in the primary tumour between treatment groups.
Methods: In total, 205 patients received neoadjuvant CT±ZOL (CT+ZOL, n=102; CT, n=103). The primary end point was pathologically assessed residual invasive tumour size (RITS) at surgery. Secondary end points were pathological complete response (pCR) rate and axillary nodal involvement. Following review of surgical pathology reports (n=195), outcome differences between groups were assessed adjusting for potential response modifiers.
Results: Baseline characteristics and CT treatments were similar. In multivariate analysis, allowing for biological and clinical factors known to influence tumour response, the adjusted mean RITS in CT and CT+ZOL groups were 27.4 and 15.5 mm, respectively, giving a difference in means of 12 mm (95% confidence interval: 3.5–20.4 mm; P=0.006). The pCR rate was 6.9% in the CT group and 11.7% in the CT+ZOL group (P=0.146). There was no difference in axillary nodal involvement (P=0.6315).
Conclusion: These data suggest a possible direct anti-tumour effect of ZOL in combination with CT, warranting formal evaluation in prospective studies
Non-invasive assessment of coronary artery bypass graft patency using 16-slice computed tomography angiography
<p>Abstract</p> <p>Background</p> <p>Invasive coronary angiography is the gold standard means of imaging bypass vessels and carries a small but potentially serious risk of local vascular complications, including myocardial infarction, stroke and death. We evaluated computed tomography as a non-invasive means of assessing graft patency.</p> <p>Methods</p> <p>Fifty patients with previous coronary artery bypass surgery who were listed for diagnostic coronary angiography underwent contrast enhanced computed tomography angiography using a 16-slice computed tomography scanner. Images were retrospectively gated to the electrocardiogram and two dimensional axial, multiplanar and three dimensional reconstructions acquired. Sensitivity, specificity, positive and negative predictive value, accuracy and level of agreement for detection of graft patency by multidetector computed tomography.</p> <p>Results</p> <p>A total of 116 grafts were suitable for analysis. The specificity of CT for the detection of graft patency was 100%, with a sensitivity of 92.8%, positive predictive value 100%, negative predictive value 85.8% and an accuracy of 94.8%. The kappa value of agreement between the two means of measuring graft patency was 0.9. Mean radiation dose was 9.0 ± 7.2 mSv for coronary angiography and 18.5 ± 4 mSv for computed tomography. Pooled analysis of eight studies, incorporating 932 grafts, confirmed a 97% accuracy for the detection of graft patency by multidetector computed tomography.</p> <p>Conclusion</p> <p>Computed tomography is an accurate, rapid and non-invasive method of assessing coronary artery bypass graft patency. However, this was achieved at the expense of an increase in radiation dose.</p
Impact of individual-level social capital on quality of life among AIDS patients in China.
With growing recognition of the social determinants of health, social capital is an increasingly important construct in international health. However, the application of social capital discourse in response to HIV infection remains preliminary. The aim of this study was to assess the impact of social capital on quality of life (QoL) among adult patients with acquired immune deficiency syndrome (AIDS). A convenient sample of 283 patients receiving antiretroviral treatment (ART) was investigated in Anhui province, China. QoL data were collected using the Medical Outcomes Study HIV Survey (MOS-HIV) questionnaire. Social capital was measured using a self-developed questionnaire. Logistic regression models were used to explore associations between social capital and QoL. The study sample had a mean physical health summary (PHS) score of 50.13 ± 9.90 and a mean mental health summary (MHS) score of 41.64 ± 11.68. Cronbach's α coefficients of the five multi-item scales of social capital ranged from 0.44 to 0.79. When other variables were controlled for, lower individual levels of reciprocity and trust were associated with a greater likelihood of having a poor PHS score (odds ratio [OR] =2.02) or PHS score (OR=6.90). Additionally, the factors of social support and social networks and ties were associated positively with MHS score (OR=2.30, OR=4.17, respectively). This is the first report to explore the effects of social capital on QoL of AIDS patients in China. The results indicate that social capital is a promising avenue for developing strategies to improve the QoL of AIDS patients in China, suggesting that the contribution of social capital should be fully exploited, especially with enhancement of QoL through social participation. Social capital development policy may be worthy of consideration
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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