104 research outputs found
Adaptive Tag Selection for Image Annotation
Not all tags are relevant to an image, and the number of relevant tags is
image-dependent. Although many methods have been proposed for image
auto-annotation, the question of how to determine the number of tags to be
selected per image remains open. The main challenge is that for a large tag
vocabulary, there is often a lack of ground truth data for acquiring optimal
cutoff thresholds per tag. In contrast to previous works that pre-specify the
number of tags to be selected, we propose in this paper adaptive tag selection.
The key insight is to divide the vocabulary into two disjoint subsets, namely a
seen set consisting of tags having ground truth available for optimizing their
thresholds and a novel set consisting of tags without any ground truth. Such a
division allows us to estimate how many tags shall be selected from the novel
set according to the tags that have been selected from the seen set. The
effectiveness of the proposed method is justified by our participation in the
ImageCLEF 2014 image annotation task. On a set of 2,065 test images with ground
truth available for 207 tags, the benchmark evaluation shows that compared to
the popular top- strategy which obtains an F-score of 0.122, adaptive tag
selection achieves a higher F-score of 0.223. Moreover, by treating the
underlying image annotation system as a black box, the new method can be used
as an easy plug-in to boost the performance of existing systems
Serum cytokine profile of pediatric patients with laboratory confirmed pneumococcal meningitis
Background: Streptococcus pneumoniae infection is a leading cause of bacterial meningitis in children with severe sequelae. Cytokines are important molecules in regulating of host inflammatory and antiinflammatory responses. So far, the cytokine profile of bacterial meningitis caused by single pathogen has been rarely reported. The aim of this study was to explore serum cytokine profile in pediatric patients with pneumococcal meningitis (PM) and its clinical relevance which could be considered as a valuable tool for differential diagnosis of PM.Methods: During 2015 & ndash;2018, 95 children with laboratory-confirmed PM were included. Of them, 63 had serum samples at admission. Ten cytokines including TNF-a, IL-12p40, IL-17A, IL-1(3, IFN-eta, GM-CSF, IL-10, CXCL-1, IL-8 and IL-13 were measured by multiplex immunoassay in sera of 63 PM patients and 55 age-matched healthy controls (HCs). Level of serum cytokines was compared with different clinical features of patients.Results: Significantly higher level of IL-10 was observed in patients than HCs (median, 2.19 vs. 1.92 pg/mL, p = 0.017). Significantly lower levels of serum IL-12p40, IL-17A and IL-1 beta were observed in patients than HCs (median, 0.68 vs. 10.12 pg/mL, p Conclusions: Our results suggested that there might be significant changes in serum pro-inflammatory and anti-inflammatory cytokines in PM children and that the determination of these cytokines may have limited value for evaluation of clinical outcome of pediatric PM.(c) 2021 The Author(s). Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences. This is an open access article under the CC BY-NC-ND license (http://creativecommons. org/licenses/by-nc-nd/4.0/).</div
Near-net forming complex shaped Zr-based bulk metallic glasses by high pressure die casting
Forming complex geometries using the casting process is a big challenge for bulk metallic glasses (BMGs), because of a lack of time of the window for shaping under the required high cooling rate. In this work, we open an approach named the “entire process vacuum high pressure die casting” (EPV-HPDC), which delivers the ability to fill die with molten metal in milliseconds, and create solidification under high pressure. Based on this process, various Zr-based BMGs were prepared by using industrial grade raw material. The results indicate that the EPV-HPDC process is feasible to produce a glassy structure for most Zr-based BMGs, with a size of 3 mm × 10 mm and with a high strength. In addition, it has been found that EPV-HPDC process allows complex industrial BMG parts, some of which are hard to be formed by any other metal processes, to be net shaped precisely. The BMG components prepared by the EVP-HPDC process possess the advantages of dimensional accuracy, efficiency, and cost compared with the ones formed by other methods. The EVP-HPDC process paves the way for the large-scale application of BMGs
An investigation of a food poisoning by Galerina sulciceps
Objective To investigate a food poisoning caused by wild mushrooms and to identify the risk factors. Methods Epidemiological investigation, morphological and phylogenetic identification, and laboratory testing were taken to analyze the poisoning event. Results All the three cases complained of abdominal pain, vomiting and diarrhea after ingesting the poisonous mushrooms, and liver function impairment was found later. One case died after 5 days. The mushroom was identified as Galerina sulciceps by morphological and phylogenetic identification. Three kinds of toxins, include α-amanitin, β-amanitin and γ-amanitin were detected in laboratory. Conclusion The incident was caused by ingesting the poisonous mushroom, Galerina sulciceps. Public education, market supervision, foodborne disease surveillance should be enhanced, and the ability of medical institutions to diagnose and treat poisonous mushrooms should be improved
Assessment of cataract surgical outcomes in settings where follow-up is poor: PRECOG, a multicentre observational study
Background Poor follow-up after cataract surgery in developing countries makes assessment of operative quality
uncertain. We aimed to assess two strategies to measure visual outcome: recording the visual acuity of all
patients 3 or fewer days postoperatively (early postoperative assessment), and recording that of only those patients
who returned for the fi nal follow-up examination after 40 or more days without additional prompting.
Methods Each of 40 centres in ten countries in Asia, Africa, and Latin America recruited 40–120 consecutive surgical
cataract patients. Operative-eye best-corrected visual acuity and uncorrected visual acuity were recorded before
surgery, 3 or fewer days postoperatively, and 40 or more days postoperatively. Clinics logged whether each patient had
returned for the fi nal follow-up examination without additional prompting, had to be actively encouraged to return, or
had to be examined at home. Visual outcome for each centre was defi ned as the proportion of patients with uncorrected
visual acuity of 6/18 or better minus the proportion with uncorrected visual acuity of 6/60 or worse, and was calculated
for each participating hospital with results from the early assessment of all patients and the late assessment of only
those returning unprompted, with results from the fi nal follow-up assessment for all patients used as the standard.
Findings Of 3708 participants, 3441 (93%) had fi nal follow-up vision data recorded 40 or more days after surgery,
1831 of whom (51% of the 3581 total participants for whom mode of follow-up was recorded) had returned to the
clinic without additional prompting. Visual outcome by hospital from early postoperative and fi nal follow-up
assessment for all patients were highly correlated (Spearman’s rs=0·74, p<0·0001). Visual outcome from fi nal followup
assessment for all patients and for only those who returned without additional prompting were also highly
correlated (rs=0·86, p<0·0001), even for the 17 hospitals with unprompted return rates of less than 50% (rs=0·71,
p=0·002). When we divided hospitals into top 25%, middle 50%, and bottom 25% by visual outcome, classifi cation
based on fi nal follow-up assessment for all patients was the same as that based on early postoperative assessment for
27 (68%) of 40 centres, and the same as that based on data from patients who returned without additional prompting
in 31 (84%) of 37 centres. Use of glasses to optimise vision at the time of the early and late examinations did not
further improve the correlations.
Interpretation Early vision assessment for all patients and follow-up assessment only for patients who return to the
clinic without prompting are valid measures of operative quality in settings where follow-up is poor
Osteogenesis Capability and Degradation Property Evaluation of Injectable Biomaterials: Comparison of Computed Tomography and Ultrasound
Injectable biomaterials, which can be physically inserted into a target site without the use of surgery, have received increasing attention in tissue engineering during the last decade. There is also a growing need for quantitative evaluation of the injectable biomaterial directly and noninvasively. The objectives of this study are to originate a quantitative noninvasive technique for evaluation of in situ forming bone biomaterials and to validate the feasibility of diagnostic ultrasound images analysis technique. The potential of ultrasound for quantitative evaluation of tissue development was compared with computed tomography (CT) in vivo. A strong correlation was witnessed between ultrasound gray-scale values (GV) and volumetric mean of CT value (HUm) (r=0.95). Meanwhile, the volume of the material area could be estimated by ultrasound maximum cross-section pixel, which demonstrates a certain consistency with CT mask volume in 3D reconstruction images (r=0.87). In conclusion, ultrasound imaging, which is corresponding with the traditional CT, can be used to evaluate osteogenesis capability and degradation property of injectable biomaterials. It may be a noninvasive, nonradioactive, and effective aid to monitor ossification and reconstruction of biomaterials at the implant region for bone defect repair
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Development and evaluation of a deep learning model for the detection of multiple fundus diseases based on colour fundus photography.
AIM: To explore and evaluate an appropriate deep learning system (DLS) for the detection of 12 major fundus diseases using colour fundus photography. METHODS: Diagnostic performance of a DLS was tested on the detection of normal fundus and 12 major fundus diseases including referable diabetic retinopathy, pathologic myopic retinal degeneration, retinal vein occlusion, retinitis pigmentosa, retinal detachment, wet and dry age-related macular degeneration, epiretinal membrane, macula hole, possible glaucomatous optic neuropathy, papilledema and optic nerve atrophy. The DLS was developed with 56 738 images and tested with 8176 images from one internal test set and two external test sets. The comparison with human doctors was also conducted. RESULTS: The area under the receiver operating characteristic curves of the DLS on the internal test set and the two external test sets were 0.950 (95% CI 0.942 to 0.957) to 0.996 (95% CI 0.994 to 0.998), 0.931 (95% CI 0.923 to 0.939) to 1.000 (95% CI 0.999 to 1.000) and 0.934 (95% CI 0.929 to 0.938) to 1.000 (95% CI 0.999 to 1.000), with sensitivities of 80.4% (95% CI 79.1% to 81.6%) to 97.3% (95% CI 96.7% to 97.8%), 64.6% (95% CI 63.0% to 66.1%) to 100% (95% CI 100% to 100%) and 68.0% (95% CI 67.1% to 68.9%) to 100% (95% CI 100% to 100%), respectively, and specificities of 89.7% (95% CI 88.8% to 90.7%) to 98.1% (95%CI 97.7% to 98.6%), 78.7% (95% CI 77.4% to 80.0%) to 99.6% (95% CI 99.4% to 99.8%) and 88.1% (95% CI 87.4% to 88.7%) to 98.7% (95% CI 98.5% to 99.0%), respectively. When compared with human doctors, the DLS obtained a higher diagnostic sensitivity but lower specificity. CONCLUSION: The proposed DLS is effective in diagnosing normal fundus and 12 major fundus diseases, and thus has much potential for fundus diseases screening in the real world
Hydroxyl super rotors from vacuum ultraviolet photodissociation of water
Free electron lasers provide a state-of-the-art tool to investigate the photochemistry of water. Here, the authors show that highly rotationally excited hydroxyl radicals, so-called “super rotors” existing above the bond dissociation energy, are observed from the photodissociation of water, which may have implications for understanding the interstellar medium
Methodology and experiences of rapid advice guideline development for children with COVID-19: responding to the COVID-19 outbreak quickly and efficiently
BACKGROUND: Rapid Advice Guidelines (RAG) provide decision makers with guidance to respond to public health emergencies by developing evidence-based recommendations in a short period of time with a scientific and standardized approach. However, the experience from the development process of a RAG has so far not been systematically summarized. Therefore, our working group will take the experience of the development of the RAG for children with COVID-19 as an example to systematically explore the methodology, advantages, and challenges in the development of the RAG. We shall propose suggestions and reflections for future research, in order to provide a more detailed reference for future development of RAGs. RESULT: The development of the RAG by a group of 67 researchers from 11 countries took 50 days from the official commencement of the work (January 28, 2020) to submission (March 17, 2020). A total of 21 meetings were held with a total duration of 48 h (average 2.3 h per meeting) and an average of 16.5 participants attending. Only two of the ten recommendations were fully supported by direct evidence for COVID-19, three recommendations were supported by indirect evidence only, and the proportion of COVID-19 studies among the body of evidence in the remaining five recommendations ranged between 10 and 83%. Six of the ten recommendations used COVID-19 preprints as evidence support, and up to 50% of the studies with direct evidence on COVID-19 were preprints. CONCLUSIONS: In order to respond to public health emergencies, the development of RAG also requires a clear and transparent formulation process, usually using a large amount of indirect and non-peer-reviewed evidence to support the formation of recommendations. Strict following of the WHO RAG handbook does not only enhance the transparency and clarity of the guideline, but also can speed up the guideline development process, thereby saving time and labor costs
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