1,357 research outputs found
An automated pattern recognition system for the quantification of inflammatory cells in hepatitis-C-infected liver biopsies
This paper presents an automated system for the quantification of inflammatory cells in hepatitis-C-infected liver biopsies. Initially, features are extracted from colour-corrected biopsy images at positions of interest identified by adaptive thresholding and clump decomposition. A sequential floating search method and principal component analysis are used to reduce dimensionality. Manually annotated training images allow supervised training. The performance of Gaussian parametric and mixture models is compared when used to classify regions as either inflammatory or healthy. The system is optimized using a response surface method that maximises the area under the receiver operating characteristic curve. This system is then tested on images previously ranked by a number of observers with varying levels of expertise. These results are compared to the automated system using Spearman rank correlation. Results show that this system can rank 15 test images, with varying degrees of inflammation, in strong agreement with five expert pathologists
Long-term effects of altered pH and temperature on the feeding energetics of the Antarctic sea urchin, Sterechinus neumayeri
Long-term effects of altered PH and temperature on the feeding energetics of the Antarctic sea urchin, Sterechinus neumayeri
This study investigated the effects of long-term incubation to near-future combined warming (+2 °C) and ocean acidification (â0.3 and â0.5 pH units) stressors, relative to current conditions (â0.3 °C and pH 8.0), on the energetics of food processing in the Antarctic sea urchin, Sterechinus neumayeri. After an extended incubation of 40 months, energy absorbed, energy lost through respiration and lost as waste were monitored through two feeding cycles. Growth parameters (mass of somatic and gonad tissues and the CHN content of gonad) were also measured. There were no significant effects of combined ocean acidification (OA) and temperature stressors on the growth of somatic or reproductive tissue. Despite more food being consumed in the low temperature control, once food processing and maintenance costs were subtracted, there were no significant effects of treatment on the scope for growth. The biggest significant differences were between amounts of food consumed during the two feeding cycles. More food was consumed by the low temperature (0 °C) control animals, indicating a potential effect of the changed conditions on digestive efficiency. Also, in November, more food was consumed, with a higher absorption efficiency, which resulted in a higher scope for growth in November than September and may reflect increased energetic needs associated with a switch to summer physiology. The effect of endogenous seasonal cycles and environmental variability on organism capacity is discussed
Clinical handover within the emergency care pathway and the potential risks of clinical handover failure (ECHO) : primary research
Background and objectives:
Handover and communication failures are a recognised threat to patient safety. Handover in emergency care is a particularly vulnerable activity owing to the high-risk context and overcrowded conditions. In addition, handover frequently takes place across the boundaries of organisations that have different goals and motivations, and that exhibit different local cultures and behaviours. This study aimed to explore the risks associated with handover failure in the emergency care pathway, and to identify organisational factors that impact on the quality of handover.
Methods:
Three NHS emergency care pathways were studied. The study used a qualitative design. Risks were explored in nine focus group-based risk analysis sessions using failure mode and effects analysis (FMEA). A total of 270 handovers between ambulance and the emergency department (ED), and the ED and acute medicine were audio-recorded, transcribed and analysed using conversation analysis. Organisational factors were explored through thematic analysis of semistructured interviews with a purposive convenience sample of 39 staff across the three pathways.
Results:
Handover can serve different functions, such as management of capacity and demand, transfer of responsibility and delegation of aspects of care, communication of different types of information, and the prioritisation of patients or highlighting of specific aspects of their care. Many of the identified handover failure modes are linked causally to capacity and patient flow issues. Across the sites, resuscitation handovers lasted between 38 seconds and 4 minutes, handovers for patients with major injuries lasted between 30 seconds and 6 minutes, and referrals to acute medicine lasted between 1 minute and approximately 7 minutes. Only between 1.5% and 5% of handover communication content related to the communication of social issues. Interview participants described a range of tensions inherent in handover that require dynamic trade-offs. These are related to documentation, the verbal communication, the transfer of responsibility and the different goals and motivations that a handover may serve. Participants also described the management of flow of patients and of information across organisational boundaries as one of the most important factors influencing the quality of handover. This includes management of patient flows in and out of departments, the influence of time-related performance targets, and the collaboration between organisations and departments. The two themes are related. The management of patient flow influences the way trade-offs around inner tensions are made, and, on the other hand, one of the goals of handover is ensuring adequate management of patient flows.
Conclusions:
The research findings suggest that handover should be understood as a sociotechnical activity embedded in clinical and organisational practice. Capacity, patient flow and national targets, and the quality of handover are intricately related, and should be addressed together. Improvement efforts should focus on providing practitioners with flexibility to make trade-offs in order to resolve tensions inherent in handover. Collaborative holistic system analysis and greater cultural awareness and collaboration across organisations should be pursued
A neurocognitive investigation of the impact of socializing with a robot on empathy for pain
To what extent can humans form social relationships with robots? In the present study, we combined functional neuroimaging with a robot socializing intervention to probe the flexibility of empathy, a core component of social relationships, towards robots. Twenty-six individuals underwent identical fMRI sessions before and after being issued a social robot to take home and interact with over the course of a week. While undergoing fMRI, participants observed videos of a human actor or a robot experiencing pain or pleasure in response to electrical stimulation. Repetition suppression of activity in the pain network, a collection of brain regions associated with empathy and emotional responding, was measured to test whether socializing with a social robot leads to greater overlap in neural mechanisms when observing human and robotic agents experiencing pain or pleasure. In contrast to our hypothesis, functional region-of-interest analyses revealed no change in neural overlap for agents after the socializing intervention. Similarly, no increase in activation when observing a robot experiencing pain emerged post-socializing. Whole-brain analysis showed that, before the socializing intervention, superior parietal and early visual regions are sensitive to novel agents, while after socializing, medial temporal regions show agent sensitivity. A region of the inferior parietal lobule was sensitive to novel emotions, but only during the pre-socializing scan session. Together, these findings suggest that a short socialization intervention with a social robot does not lead to discernible differences in empathy towards the robot, as measured by behavioural or brain responses. We discuss the extent to which long-term socialization with robots might shape social cognitive processes and ultimately our relationships with these machines.
This article is part of the theme issue âFrom social brains to social robots: applying neurocognitive insights to humanârobot interactionâ
Long-term surgical and patient-reported outcomes of Hirschsprung Disease
Background: Information is needed regarding the complex relationships between long-term functional outcomes and health-related quality of life (HRQoL) in Hirschsprung's Disease (HSCR). We describe longterm outcomes across multiple domains, completing a core outcome set through to adulthood. Methods: HSCR patients operated at a single center over a 35-year period (1978-2013) were studied. Patients completed detailed questionnaires on bowel and urologic function, and HRQOL. Patients with learning disability (LD) were excluded. Outcomes were compared to normative data. Data are reported as median [IQR] or mean (SD). Results: 186 patients (median age 28 [18-32] years; 135 males) completed surveys. Bowel function was reduced (BFS 17 [14-19] vs. 19 [19-20], p < 0.0001;eta(2) = 0.22). Prevalence and severity of fecal soiling and fecal awareness improved with age ( p < 0.05 for both). Urinary incontinence was more frequent than controls, most of all in 13-26y females (65% vs. 31%, p = 0.003). In adults, this correlated independently with constipation symptoms (OR 3.18 [1.4-7.5], p = 0.008). HRQoL outcomes strongly correlated with functional outcome: 42% of children demonstrated clinically significant reductions in overall PedsQL score, and poor bowel outcome was strongly associated with impaired QOL (B = 22.7 [12.7- 32.7], p < 0.001). In adults, GIQLI scores were more often impacted in patients with extended segment disease. SF-36 scores were reduced relative to population level data in most domains, with large effect sizes noted for females in General Health (g = 1.19) and Social Wellbeing (g = 0.8). Conclusion: Functional impairment is common after pull-through, but bowel function improves with age. Clustering of poor functional outcomes across multiple domains identifies a need for early recognition and long-term support for these patients. (C) 2021 Elsevier Inc. All rights reserved.Peer reviewe
Coalescence in the 1D Cahn-Hilliard model
We present an approximate analytical solution of the Cahn-Hilliard equation
describing the coalescence during a first order phase transition. We have
identified all the intermediate profiles, stationary solutions of the noiseless
Cahn-Hilliard equation. Using properties of the soliton lattices, periodic
solutions of the Ginzburg-Landau equation, we have construct a family of ansatz
describing continuously the processus of destabilization and period doubling
predicted in Langer's self similar scenario
Unrestricted faecal calprotectin testing performs poorly in the diagnosis of inflammatory bowel disease in patients in primary care
BACKGROUND: Faecal calprotectin (FC) measurement distinguishes patients with inflammatory bowel disease (IBD) from those with irritable bowel syndrome but evidence of its performance in primary care is limited. AIMS: To assess the yield of IBD from FC testing in primary care. METHODS: Retrospective review of hospital records to assess the outcome following FC testing in primary care. Investigations for all patients undergoing FC testing in a single laboratory for 6âmonths from 1 October 2013 to 28 February 2014 were reviewed. RESULTS: 410 patients (162 male; median age 42; range 16-91) were included. FC>50â”g/g was considered positive (FC+). 148/410 (36.1%; median age 44 (17-91)) were FC+ (median FC 116.5â”g/g (51-1770)). 122/148 FC-positive patients (82.4%) underwent further investigation. 97 (65.5%) underwent lower gastrointestinal endoscopy (LGIE), of which 7 (7.2%) had IBD. 49/262 (18.7%) FC-negative (FC-) patients (FC â€50â”g/g) (median age 47 (19-76)) also underwent LGIE, of whom 3 (6.1%) had IBD.IBD was diagnosed in 11/410 (2.7%; 4 ulcerative colitis, 3 Crohn's disease, 4 microscopic colitis). 8/11 were FC+ (range 67-1170) and 3 FC-. At a 50â”g/g threshold, sensitivity for detecting IBD was 72.7%, specificity 64.9%, positive predictive value (PPV) 5.41% and negative predictive value 98.9%. Increasing the threshold to 100â”g/g reduced the sensitivity of the test for detecting IBD to 54.6%. CONCLUSIONS: FC testing in primary care has low sensitivity and specificity with poor PPV for diagnosing IBD. Its use needs to be directed to those with a higher pretest probability of disease. Local services and laboratories should advise general practitioners accordingly
Nonlinear saturation of electrostatic waves: mobile ions modify trapping scaling
The amplitude equation for an unstable electrostatic wave in a multi-species
Vlasov plasma has been derived. The dynamics of the mode amplitude is
studied using an expansion in ; in particular, in the limit
, the singularities in the expansion coefficients are
analyzed to predict the asymptotic dependence of the electric field on the
linear growth rate . Generically , as
, but in the limit of infinite ion mass or for
instabilities in reflection-symmetric systems due to real eigenvalues the more
familiar trapping scaling is predicted.Comment: 13 pages (Latex/RevTex), 4 postscript encapsulated figures which are
included using the utility "uufiles". They should be automatically included
with the text when it is downloaded. Figures also available in hard copy from
the authors ([email protected]
The Millennium Galaxy Catalogue: Dynamically Close Galaxy Pairs and the Global Merger Rate
We derive the number of dynamically close companions per galaxy () and
their total luminosity () for galaxies in the Millennium Galaxy Catalogue:
is similar to the fraction of galaxies in close pairs and is directly
related to the galaxy merger rate. We find and
for galaxies with and , for galaxies with , with
. The integrated merger rate to for both samples is about 20
%, but this depends sensitively on the fraction of kinematic pairs that are
truly undergoing a merger (assumed here to be 50%), the evolution of the merger
rate (here as ) and the adopted timescale for mergers (0.2 and 0.5 Gyr
for each sample, respectively). Galaxies involved in mergers tend to be
marginally bluer than non-interacting galaxies and show an excess of both
early-type and very late-type objects and a deficiency of intermediate-type
spirals. This suggests that interactions and mergers partly drive the star
formation and morphological evolution of galaxies.Comment: 26 pages, 3 figures, AJ accepted for publicatio
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