We consider the lack of consensus about an appropriate theoretical framework linking sub-indicators as a defining characteristic of composite indicators. This intrinsic feature implies uncertainties ...about the appropriate normalization and aggregation of the raw data. The two are related: index theory offers some valuable guidelines about their connection. Yet these do not fully solve the basic problem of expert disagreement. We embed such (residual) disagreement in the aggregation method itself. Specifically, we apply an impartial benefit-of-the-doubt weighting procedure, where weight restrictions incorporate the available information on experts’ opinions. We apply this procedure to the dynamic performance assessment of EU Internal Market effects, thereby highlighting its capacity to disaggregate member states’ observed performance shifts into changes
relative to benchmarks and performance changes
of the benchmarks (i.e. catching up versus genuine progress). Our results indicate that the latter factor is more important in explaining the observed progress.
This study focuses on the newly described ionospheric feature, called double‐peak subauroral ion drift (DSAID), which is a subclass of the well‐known single‐peak SAID. Double‐layer Region 2 (R2) ...field aligned currents (FACs) could be the main driver of DSAID. Our aim is to gain new insights into the development of DSAID during its two‐stage progression. Observational results are provided by five scenarios, each demonstrating a certain progression sequence of DSAID. Results show that SAID/DSAID occurred during flux transfer events and was accompanied by flow channels (FCs) associated with dayside magnetopause (FC‐2) and nightside magnetotail (FC‐3) reconnections, with westward electrojet (eastward FC), and with auroral streamers (FC‐4). In the premidnight magnetic local time (MLT) sector of stage 2, DSAID development was due to the short‐circuiting of the reconnection‐injected plasma jets during substorms or pseudobreakups. Thus, the related ring current pressure buildup enhanced the downward R2 FACs leading to double/multiple circuits forming double‐layer R2 FACs. During the midnight MLT hours of stage 2, DSAID development was closely related to the westward traveling surge (WTS)/substorm current wedge (SCW). WTS/SCW‐related strong upward R1 FACs closed with meriodional currents producing eastward and downward (i.e., downward R2 FAC‐style) return currents enhancing the downward R2 FACs and thus leading to double/multiple circuits forming double‐layer R2 FACs. Auroral streamers/FC‐4 represent a substorm substructure and their occurrence with DSAID after stage 2 demonstrates that this substructure occasionally includes DSAID. Our results demonstrate also that the short‐circuited system underlying SAID/DSAID acted sometimes as a current generator and sometimes as a voltage generator.
Key Points
DSAID appeared with various types of FCs during FTEs.
In the pre ‐midnight MLT sector: underlying short‐circuited system acted as a current/voltage generator.
In the midnight MLT sector: DSAID development was closely related to the WTS)/SCW.
Analyzing and classifying Human Epithelial type 2 (HEp-2) cells using Indirect Immunofluorescence protocol has been the golden standard for detecting connective tissue diseases such as Rheumatoid ...Arthritis. However, this suffers from numerous shortcomings such as being subjective as well as time and labor intensive. Recently, several studies explore the advantages of artificial systems to automate the process, not only to reduce the test turn-around time but also to deliver more consistent results. In this paper, we extend the conventional bag of word models from Euclidean space to non-Euclidean Riemannian manifolds and utilize them to classify the HEp-2 cells. The main motivation comes from the observation that HEp-2 cells can be efficiently described by symmetric positive definite matrices which lie on a Riemannian manifold. With this motivation, we first discuss an intrinsic bag of Riemannian words model. We then propose Fisher tensors which can in turn encode additional information about the distribution of the signatures in a bag of word model. Experiments on two challenging HEp-2 images datasets, namely ICPRContest and SNPHEp-2 show that the proposed methods obtain notable improvements in discrimination accuracy, in comparison to baseline and several state-of-the-art methods. The proposed framework, while hand-crafted towards cell classification, is a generic framework for object recognition. This is supported by assessing the performance of our proposal on a challenging texture classification task.
•Exploring region covariance descriptors for representing HEp-2 cells.•Introducing bag of Riemannian words for efficient classification of HEp-2 cells.•Proposing Fisher tensors as an extension of bag of Riemannian words for classifying HEp-2 cells.•Thorough experiments show proposed approach outperforms state-of-the-art methods.
Background subtraction is a fundamental low-level processing task in numerous computer vision applications. The vast majority of algorithms process images on a pixel-by-pixel basis, where an ...independent decision is made for each pixel. A general limitation of such processing is that rich contextual information is not taken into account. We propose a block-based method capable of dealing with noise, illumination variations, and dynamic backgrounds, while still obtaining smooth contours of foreground objects. Specifically, image sequences are analyzed on an overlapping block-by-block basis. A low-dimensional texture descriptor obtained from each block is passed through an adaptive classifier cascade, where each stage handles a distinct problem. A probabilistic foreground mask generation approach then exploits block overlaps to integrate interim block-level decisions into final pixel-level foreground segmentation. Unlike many pixel-based methods, ad-hoc postprocessing of foreground masks is not required. Experiments on the difficult Wallflower and I2R datasets show that the proposed approach obtains on average better results (both qualitatively and quantitatively) than several prominent methods. We furthermore propose the use of tracking performance as an unbiased approach for assessing the practical usefulness of foreground segmentation methods, and show that the proposed approach leads to considerable improvements in tracking accuracy on the CAVIAR dataset.
leucine-rich repeat structure Bella, J; Hindle, K. L; McEwan, P. A ...
Cellular and molecular life sciences : CMLS,
08/2008, Letnik:
65, Številka:
15
Journal Article
Recenzirano
The leucine-rich repeat is a widespread structural motif of 20-30 amino acids with a characteristic repetitive sequence pattern rich in leucines. Leucine-rich repeat domains are built from tandems of ...two or more repeats and form curved solenoid structures that are particularly suitable for protein-protein interactions. Thousands of protein sequences containing leucine-rich repeats have been identified by automatic annotation methods. Three-dimensional structures of leucine-rich repeat domains determined to date reveal a degree of structural variability that translates into the considerable functional versatility of this protein superfamily. As the essential structural principles become well established, the leucine-rich repeat architecture is emerging as an attractive framework for structural prediction and protein engineering. This review presents an update of the current understanding of leucine-rich repeat structure at the primary, secondary, tertiary and quaternary levels and discusses specific examples from recently determined three-dimensional structures.
Summary
Background Multiple questionnaires to screen for psoriatic arthritis (PsA) have been developed but the optimal screening questionnaire is unknown.
Objectives To compare three PsA screening ...questionnaires in a head‐to‐head study using CASPAR (the Classification Criteria for Psoriatic Arthritis) as the gold standard.
Methods This study recruited from 10 U.K. secondary care dermatology clinics. Patients with a diagnosis of psoriasis, not previously diagnosed with PsA, were given all three questionnaires. All patients who were positive on any questionnaire were invited for a rheumatological assessment. Receiver operating characteristic (ROC) curves were used to compare the sensitivity, specificity and area under the curve of the three questionnaires according to CASPAR criteria.
Results In total, 938 patients with psoriasis were invited to participate and 657 (70%) patients returned the questionnaires. One or more questionnaires were positive in 314 patients (48%) and 195 (62%) of these patients attended for assessment. Of these, 47 patients (24%) were diagnosed with PsA according to the CASPAR criteria. The proportion of patients with PsA increased with the number of positive questionnaires (one questionnaire, 19·1%; two, 34·0%; three, 46·8%). Sensitivities and specificities for the three questionnaires, and areas under the ROC curve were, respectively: Psoriatic Arthritis Screening Evaluation (PASE), 74·5%, 38·5%, 0·594; Psoriasis Epidemiology Screening Tool (PEST), 76·6%, 37·2%, 0·610; Toronto Psoriatic Arthritis Screen (ToPAS), 76·6%, 29·7%, 0·554. The majority of patients with a false positive response had degenerative or osteoarthritis.
Conclusion Although the PEST and ToPAS questionnaires performed slightly better than the PASE questionnaire at identifying PsA, there is little difference between these instruments. These screening tools identify many cases of musculoskeletal disease other than PsA.
What’s already known about this topic?
•
A number of screening questionnaires have been developed to detect psoriatic arthritis in people with psoriasis.
•
Each questionnaire has shown good and largely equivalent performance, in terms of specificity and sensitivity, in the development cohorts.
•
What is needed is a head‐to‐head study in a new cohort of patients with psoriasis.
What does this study add?
•
Each of the questionnaires performed worse in this new cohort of patients in secondary care, with no significant differences between them.
•
Both sensitivity and specificity were worse, although the study design was likely to underestimate the specificity and overestimate the sensitivity.
•
Screening questionnaires such as these will detect other musculoskeletal diseases in addition to psoriatic arthritis and additional information may be needed to enhance their specificity.
Complex trauma is a significant public health issue with detrimental health, interpersonal and psychological impacts, which can impede client recovery and result in multiple representations. 'Trauma ...Informed Practice' (TIP) is an evidence-based model which ensures safe and effective services for clients and staff. This study examines health professional's use of TIP, and the motivators, enablers and barriers to implementation in a multidisciplinary setting.
A mixed methods study with 24 front-line clinicians and managers within a community health setting in Australia. A purpose designed, expert validated TIP checklist was completed, followed by semi-structured focus groups. Survey data was reported using descriptive statistics. Focus group data was digitally recorded, transcribed and thematically analysed.
Ten key factors were identified motivating, restricting or enabling TIP implementation. Seven were organisational factors including supportive and informed management, flexibility of service models, levels of service demands, resource availability, education opportunities, good client outcomes, and reporting requirements. Philosophical approach, team orientation, and vicarious trauma/stress management were three individual professional factors. Critically, alignment in two ways was necessary for successful implementation, that is: in knowledge and understanding across organisational role levels - clinician, manager and executive; and, in professional philosophy and team orientation of individual clinicians.
Providing TIP is essential for ensuring optimum client outcomes for trauma survivors and for maintaining workforce wellbeing. Although the increasing uptake to TIP is evident within the health setting, further attention is required to address the tension between service models focused on efficiently servicing whole populations and those attuned to effectively meeting the needs of high risk groups. A complex strategy to unite therapeutic and managerial goals is necessary if client, professional and organisational needs are to be effectively met.
This study employs data drawn from the 2000 Agricultural Resource Management Survey, a U.S. Department of Agriculture-sponsored farmers' survey. The article estimates returns to scale relationships ...across dairy farms of different sizes and across different regions, incorporating variables hypothesized to influence farm performance. Results point to significant scale economies in U.S. dairy farms and underscore the importance of taking account of inefficiency when estimating scale economies. Contrary to previous research, the preferred cost function specification does not show a region of decreasing returns to scale. This finding helps explain why the average size of dairy farms has been increasing.
Abstract
We demonstrate that the inference of galaxy stellar masses via spectral energy distribution (SED) fitting techniques for galaxies formed in the first billion years after the Big Bang carries ...fundamental uncertainties owing to the loss of star formation history (SFH) information from the very first episodes of star formation in the integrated spectra of galaxies. While this early star formation can contribute substantially to the total stellar mass of high-redshift systems, ongoing star formation at the time of detection outshines the residual light from earlier bursts, hampering the determination of accurate stellar masses. As a result, order-of-magnitude uncertainties in stellar masses can be expected. We demonstrate this potential problem via direct numerical simulation of galaxy formation in a cosmological context. In detail, we carry out two cosmological simulations with significantly different stellar feedback models, which span a significant range in SFH burstiness. We compute the mock SEDs for these model galaxies at
z
= 7 via calculations of 3D dust radiative transfer, and then backward fit these SEDs with
prospector
SED fitting software. The uncertainties in derived stellar masses that we find for
z
> 7 galaxies motivate the development of new techniques and/or priors for SFH to model star formation in the early Universe.
Cycloparaphenylenes have promise as novel fluorescent materials. However, shifting their fluorescence beyond 510 nm is difficult. Herein, we computationally explore the effect of incorporating ...electron accepting and electron donating units on CPP photophysical properties at the CAM-B3LYP/6-311G** level. We demonstrate that incorporation of donor and acceptor units may shift the CPP fluorescence as far as 1193 nm. This computational work directs the synthesis of bright red-emitting CPPs. Furthermore, the nanohoop architecture allows for interrogation of strain effects on common conjugated polymer donor and acceptor units. Strain results in a bathochromic shift
versus
linear variants, demonstrating the value of using strain to push the limits of low band gap materials.
Computational studies reveal near-IR emitting nanohoops and the effect of strain on donor and acceptor units used in conjugated polymers.
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