3,324 research outputs found
Analysis of the children's dynamic and static stereopsis of intermittent exotropia
AIM: To compare and analyze the stereopsis of intermittent exotropia children under the different backgrounds of dynamic stimuli and static stimuli.<p>METHODS: We collected 56 children(male 26, female 30 with intermittent exotropia at the age from 5y to 12y and examined their stereopsis under the different backgrounds of dynamic stimuli and static stimuli using a multidimensional sense perception training software. The differences between the dynamic stereopsis and static stereopsis were compared.<p>RESULTS: Totally 17 cases(30%)had both dynamicstereopsis and static stereopsis, 39 cases(70%)had either dynamic or static stereopsis deficit, only 10 cases(26%)had dynamic stereopsis, 25 cases(64%)static stereopsis left and 4 cases(10%)were without any form of stereopsis. The positive rate of dynamic stereopsis was better than the positive rate of static stereopsis, with statistical significance(<i>P</i><0.05).<p>CONCLUSION: Dynamicstereopsis is better than the static stereopsis to intermittent exotropia children
Determining Singularity-Free Inner Workspace through Offline Conversion of Assembly Modes for a 3-RRR PPM
The existing singularity avoidance methods have deficiencies, such as the conditionality of the online conversion of the assembly modes (AMs) and the kinematically redundant manipulator with the predicament of the prototype design and added complexity of the mechanism. To address these issues, a method to determine a singularity-free inner workspace through offline conversion of the AMs of the 3-RRR planar parallel manipulator (PPM) is presented. Based on the geometric relations among rods of the manipulator during the occurrence of singularity, and the singular points at or near the boundary of the workspace are permitted, the AMs and ranges of the orientation angle of the moving platform corresponding to the inner singularity-free workspace are determined through a three-dimensional search method. The simulation and experimental comparisons indicate that singular-free paths related to the constant or variable orientation angle of the moving platform can be planned on the singularity-free inner workspace
Contrastive Attention for Automatic Chest X-ray Report Generation
Recently, chest X-ray report generation, which aims to automatically generate
descriptions of given chest X-ray images, has received growing research
interests. The key challenge of chest X-ray report generation is to accurately
capture and describe the abnormal regions. In most cases, the normal regions
dominate the entire chest X-ray image, and the corresponding descriptions of
these normal regions dominate the final report. Due to such data bias,
learning-based models may fail to attend to abnormal regions. In this work, to
effectively capture and describe abnormal regions, we propose the Contrastive
Attention (CA) model. Instead of solely focusing on the current input image,
the CA model compares the current input image with normal images to distill the
contrastive information. The acquired contrastive information can better
represent the visual features of abnormal regions. According to the experiments
on the public IU-X-ray and MIMIC-CXR datasets, incorporating our CA into
several existing models can boost their performance across most metrics. In
addition, according to the analysis, the CA model can help existing models
better attend to the abnormal regions and provide more accurate descriptions
which are crucial for an interpretable diagnosis. Specifically, we achieve the
state-of-the-art results on the two public datasets.Comment: Appear in Findings of ACL 2021 (The Joint Conference of the 59th
Annual Meeting of the Association for Computational Linguistics and the 11th
International Joint Conference on Natural Language Processing (ACL-IJCNLP
2021)
扩张型心肌病患者尿酸水平与恶性室性心律失常研究
To analyze the relation between uric acid (UA) and malignant ventricular arrhythmia (MVA) in patient with dilated cardiomyopathy (DCM), and to provide clinic basis for predicting the risk of death. Methods: We divide the 48 patient with dilated cardiomyopathy into 2 groups according to MVA. They are MVA group and normal group. We analyze the difference of the incidence of hyperuricemia (HUA) between the 2 groups. Results: ⑴ The indices of age, creatinine (Crea), uric acid, N-terminal pro-brain natriuretic peptide (NT-proBNP), left ventricular end-diastolic volume (LVEDV) and the percentage of HUA and ventricular late potential (VLP%) in MVA group are higher than those in normal group, as to left ventricular ejection fraction (LVEF), the normal group is higher than that in MVA group. And the difference between the two groups is statistically significant. There is no statistically difference in the indices of proportion of men, systolic blood pressure (SBP) and heart rate(HR) between the 2 groups. ⑵Using logistic regression, MVA was positively related to UA, VLP, age, NT-proBNP and LVEDV, and it is negatively related to LVEF. Conclusions: MVA is closely related to uric acid. Uric acid might be used to predict the incidence of MVA in patient with DCM.目的 分析扩张型心肌病患者血浆尿酸水平与恶性心律失常(MVA)关系,为评估扩张型心肌病死亡风险提供临床依据。方法 利用2008年2月至2014年8月本院住院诊断扩张型心肌病患者(共48例)作为研究对象,依据24小时动态心电图检查是否出现恶性室性心律失常,将研究对象分为恶性室性心律失常组MVA(+)及对照组MVA(–),分析恶性MVA与尿酸关系。结果 (1)年龄、肌酐、尿酸、NT-proBNP、左室舒张末容积(LVEF)及心室晚电位(VLP)阳性率皆为MVA(+)组高于对照组;左室射血分数则相反,为对照组高于MVA(+)组,上述指标的组间差异皆有统计学意义。而性别比、收缩压、舒张压、心率之间的组间差异没有统计学意义,尚不能认为这些指标在两组间有所不同。(2)采用logistic回归分析研究MVA的相关危险因素,MVA与VLP、Age、NT-proBNP、尿酸及LVEDV呈正相关,与LVEF呈负相关。在排除其他因素对MVA的干扰后,尿酸仍是MVA重要的危险因素,其OR值为1.196(P<0.05)。结论 扩张型心肌病患者恶性室性心律失常与其尿酸水平密切相关,可能可以使用尿酸水平预测恶性室性心律失常的发生
Multi-Locus Analysis Reveals A Different Pattern of Genetic Diversity for Mitochondrial and Nuclear DNA between Wild and Domestic Pigs in East Asia
BACKGROUND: A major reduction of genetic diversity in mtDNA occurred during the domestication of East Asian pigs. However, the extent to which genetic diversity has been lost in the nuclear genome is uncertain. To reveal levels and patterns of nucleotide diversity and to elucidate the genetic relationships and demographic history of domestic pigs and their ancestors, wild boars, we investigated 14 nuclear markers (including 8 functional genes, 2 pseudogenes and 4 intergenic regions) from 11 different chromosomes in East Asia-wide samples and pooled them with previously obtained mtDNA data for a combined analysis. PRINCIPAL FINDINGS: The results indicated that domestic pigs and wild boars possess comparable levels of nucleotide diversity across the nuclear genome, which is inconsistent with patterns that have been found in mitochondrial genome. CONCLUSIONS: This incongruence between the mtDNA and nuclear genomes is suggestive of a large-scale backcross between male wild boars and female domestic pigs in East Asia. Our data reveal the impacts of founder effects and backcross on the pig genome and help us better understand the complex demographic histories of East Asian pigs, which will be useful for future work on artificial selection
Development of an improved microneutralization assay for respiratory syncytial virus by automated plaque counting using imaging analysis
BACKGROUND: Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in infants and young children. Although several experimental RSV vaccines are under investigation, immuno therapy is the only treatment currently available. In assessing the immunogenicity of various vaccine formulations, a plaque reduction neutralization assay for the evaluation of RSV neutralizing antibody has been widely used. The method produces reliable results, but it is tedious and labor intensive as it relies on manual counting by laboratory personnel. To facilitate evaluation of phase II and phase III vaccine clinical trials, a more rapid, reliable and efficient neutralization assay is needed. RESULTS: An improved microneutralization assay for quantifying RSV neutralizing antibodies was developed using an ImmunoSpot(® )Series I Analyzer (Cellular Technology Ltd., Cleveland, OH) for automated plaque counting. The method is an improvement of the established classical microneutralization assay in which immunostained plaques on transparent tissue culture plates are counted manually under a dissecting microscope. Image analyzer technology allows for fully automated counting of plaques distributed throughout an entire well. Adjustments, such as the use of opaque tissue culture plates and the TMB substrate, True Blue™ (KPL, Gaithersburg, MD), were required to adapt the assay for optimal detection of plaques by the image analyzer. The suitability and the accuracy of the method for counting RSV plaques were determined by comparative testing of a reference serum and two control sera by manual and automated counting methods. The results showed that the two methods were highly correlated (R = 0.9580) and the titers generated by them were within two-fold. CONCLUSION: Our results demonstrate that the semi-automated assay is rapid and reliable. It provides results within two fold to the classical plaque microneutralization assay and is readily applied to the evaluation of neutralizing antibody titers in sera obtained from epidemiology or vaccine clinical trials
Increasing hypoxia in the Changjiang Estuary during the last three decades deciphered from sedimentary redox-sensitive elements
Abstract(#br)Ranked as one of the world’s largest seasonal hypoxic water bodies (Dissolved oxygen, DO≤2 mg l − 1 ), the Changjiang hypoxia has been reported to grow rapidly worse in recent decades according to cruise observations, but it has been seldom studied by sedimentary records. In this paper, four gravity cores (E1-E4), retrieved from the Changjiang Estuary, were dated by excess 210 Pb and analyzed with grain-size compositions, total organic carbon (TOC) contents, and RSEs (redox sensitive elements) compositions. We aim to decipher RSEs enrichment characteristics and controlling mechanisms in the Changjiang Estuary. The results show that Mo and V enrichment is highly promoted by particle absorption and FeMn redox cycling at the shallow estuarine environment (E1 and E2) with occasional hypoxic disturbances. Scavenging of Mo and V by organic complexation becomes significant at the hypoxic center (E3), together with great influence by FeMn redox cycling, but they do not work effectively for U enrichment because of its easy remobilization and abundant riverine input. Moreover, upcore increasing trends of Mo, V, and U in E3 match well with a general lowering trend of bottom water DO minima since the mid-1980s. There are two progressive hypoxic development stages intercalated with a less DO-depleted period 1991–1997 as shown by both cruise observations and RSEs/Al records. These findings are vital to better understanding coastal hypoxic development and RSEs enrichment mechanisms in the seasonal hypoxic settings, because hypoxia is predicted to increase in the near future due to intensifying human disturbances
Qubitization of Bosons
A binary mapping from Fock space of bosonic state to qubits is given. Based
on the binary mapping, we construte an algorithm of qubitization of bosons with
complexity O(log(N)). As an example, the algorithm of qubitization of bosons in
matrix product state to simulate real time dynamics of Yukawa coupling is
realized. The calculation error bar is estimated by random sampling method.
This proposal may be achieved in superconductivity noisy intermediate--scale
quantum computer not far future.Comment: 7 pages, 4 figure
- …