The purpose of this study was to investigate 62 subjects in Wuhan, China, with laboratory-confirmed coronavirus disease (COVID-19) pneumonia and describe the CT features of this epidemic disease.
A ...retrospective study of 62 consecutive patients with laboratory-confirmed COVID-19 pneumonia was performed. CT images and clinical data were reviewed. Two thoracic radiologists evaluated the distribution and CT signs of the lesions and also scored the extent of involvement of the CT signs. The Mann-Whitney
test was used to compare lesion distribution and CT scores. The chi-square test was used to compare the CT signs of early-phase versus advanced-phase COVID-19 pneumonia.
A total of 62 patients (39 men and 23 women; mean ± SD age, 52.8 ± 12.2 years; range, 30-77 years) with COVID-19 pneumonia were evaluated. Twenty-four of 30 patients who underwent routine blood tests (80.0%) had a decreased lymphocyte count. Of 27 patients who had their erythrocyte sedimentation rate and high-sensitivity C-reactive protein level assessed, 18 (66.7%) had an increased erythrocyte sedimentation rate, and all 27 (100.0%) had an elevated high-sensitivity C-reactive protein level. Multiple lesions were seen on the initial CT scan of 52 of 62 patients (83.9%). Forty-eight of 62 patients (77.4%) had predominantly peripheral distribution of lesions. The mean CT score for the upper zone (3.0 ± 3.4) was significantly lower than that for the middle (4.5 ± 3.8) and lower (4.5 ± 3.7) zones (
= 0.022 and
= 0.020, respectively), and there was no significant difference in the mean CT score of the middle and lower zones (
= 1.00). The mean CT score for the anterior area (4.4 ± 4.1) was significantly lower than that for the posterior area (7.7 ± 6.3) (
= 0.003). CT findings for the patients were as follows: 25 patients (40.3%) had ground-glass opacities (GGO), 21 (33.9%), consolidation; 39 (62.9%), GGO plus a reticular pattern; 34 (54.8%), vacuolar sign; 28 (45.2%), microvascular dilation sign; 35 (56.5%), fibrotic streaks; 21 (33.9%), a subpleural line; and 33 (53.2%), a subpleural transparent line. With regard to bronchial changes seen on CT, 45 patients (72.6%) had air bronchogram, and 11 (17.7%) had bronchus distortion. In terms of pleural changes, CT showed that 30 patients (48.4%) had pleural thickening, 35 (56.5%) had pleural retraction sign, and six (9.7%) had pleural effusion. Compared with early-phase disease (≤ 7 days after the onset of symptoms), advanced-phase disease (8-14 days after the onset of symptoms) was characterized by significantly increased frequencies of GGO plus a reticular pattern, vacuolar sign, fibrotic streaks, a subpleural line, a subpleural transparent line, air bronchogram, bronchus distortion, and pleural effusion; however, GGO significantly decreased in advanced-phase disease.
CT examination of patients with COVID-19 pneumonia showed a mixed and diverse pattern with both lung parenchyma and the interstitium involved. Identification of GGO and a single lesion on the initial CT scan suggested early-phase disease. CT signs of aggravation and repair coexisted in advanced-phase disease. Lesions presented with a characteristic multifocal distribution in the middle and lower lung regions and in the posterior lung area. A decreased lymphocyte count and an increased high-sensitivity C-reactive protein level were the most common laboratory findings.
The etiology of non-genetic intellectual disability (ID) is not fully known, and we aimed to identify the prenatal, perinatal and neonatal risk factors for ID.
PubMed and Embase databases were ...searched for studies that examined the association between pre-, peri- and neonatal factors and ID risk (keywords "intellectual disability" or "mental retardation" or "ID" or "MR" in combination with "prenatal" or "pregnancy" or "obstetric" or "perinatal" or "neonatal". The last search was updated on September 15, 2015. Summary effect estimates (pooled odds ratios) were calculated for each risk factor using random effects models, with tests for heterogeneity and publication bias.
Seventeen studies with 55,344 patients and 5,723,749 control individuals were eligible for inclusion in our analysis, and 16 potential risk factors were analyzed. Ten prenatal factors (advanced maternal age, maternal black race, low maternal education, third or more parity, maternal alcohol use, maternal tobacco use, maternal diabetes, maternal hypertension, maternal epilepsy and maternal asthma), one perinatal factor (preterm birth) and two neonatal factors (male sex and low birth weight) were significantly associated with increased risk of ID.
This systemic review and meta-analysis provides a comprehensive evidence-based assessment of the risk factors for ID. Future studies are encouraged to focus on perinatal and neonatal risk factors and the combined effects of multiple factors.
Due to their low temperatures, the Arctic, Antarctic and Tibetan Plateau are known as the three polar regions of the Earth. As the most remote regions of the globe, the occurrence of persistent ...organic pollutants (POPs) in these polar regions arouses global concern. In this paper, we review the literatures on POPs involving these three polar regions. Overall, concentrations of POPs in the environment (air, water, soil and biota) have been extensively reported, with higher levels of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) detected on the Tibetan Plateau. The spatial distribution of POPs in air, water and soil in the three polar regions broadly reflects their distances away from source regions. Based on long-term data, decreasing trends have been observed for most “legacy POPs”. Observations of transport processes of POPs among multiple media have also been carried out, including air–water gas exchange, air–soil gas exchange, emissions from melting glaciers, bioaccumulations along food chains, and exposure risks. The impact of climate change on these processes possibly enhances the re-emission processes of POPs out of water, soil and glaciers, and reduces the bioaccumulation of POPs in food chains. Global POPs transport model have shown the Arctic receives a relatively small fraction of POPs, but that climate change will likely increase the total mass of all compounds in this polar region. Considering the impact of climate change on POPs is still unclear, long-term monitoring data and global/regional models are required, especially in the Antarctic and on the Tibetan Plateau, and the fate of POPs in all three polar regions needs to be comprehensively studied and compared to yield a better understanding of the mechanisms involved in the global cycling of POPs.
Display omitted
•Levels and spatiotemporal distribution of POPs in the three polar regions are reviewed.•Influence of climate change on the transport and accumulation of POPs are addressed.•The fate of POPs in the three polar environments are synthesized.•Knowledge gaps and future perspectives regarding POPs over the three polar regions are discussed.
Current researches, knowledge gaps and future perspectives of POPs in three polar regions are reviewed.
Dear Editor, N6-methyladenosine （m6A） has been demonstrated to be ubiquitous in several types of eukaryotic RNAs, including messenger RNA （mRNA）, transfer RNA （tRNA）, ribosomal RNA （rRNA）, long ...non-coding RNA （lncRNA）, and small nuclear RNA （snRNA） 1. The recent discoveries of RNA m6A methyltransferase complex METTL3/METTL14/WTAP and demethylases FTO and ALKBH5 prove the reversibility of m6A modification 2-6. This modification plays important roles in various biological processes, including circadian rhythms 7,
Objectives
To investigate CT images of 100 confirmed COVID-19 pneumonia patients to describe the lesion distribution, CT signs, and evolution during different courses.
Methods
A retrospective study ...of 100 COVID-19 pneumonia patients without ARDS was performed, and CT scans were reviewed. A COVID-19 pneumonia course diagram was drawn. Mann-Whitney
U
test was used to compare the lesion distribution and CT scores,
χ
2
test was used to compare the CT findings between different stages.
Results
A total of 272 CT scans from 100 patients (mean age, 52.3 years ± 13.1) were investigated. Four patients with lung abnormalities on CT first showed negative RT-PCR result and turned positive afterwards. One hundred sixty-nine (62.1%) showed predominantly peripheral distribution. The CT scores of the upper zone (3.4 ± 3.6) were significantly lower than those of the middle (5.0 ± 3.9) and lower (4.8 ± 3.6) zones (
p
< 0.001). The CT scores of the anterior zones (4.9 ± 4.7) were significantly lower than those of the posterior zones (8.4 ± 6.2) (
p
< 0.001). In the early rapid progressive stage (1~7 days), ground glass opacity (GGO) plus reticular pattern (58.1%), GGO plus consolidation (43.0%), and GGO (41.9%) were all common. In the advanced stage (8~14 days), GGO plus consolidation (79.8%) and repairing CT signs (subpleural line, bronchus distortion, and fibrotic strips) showed a significant increase (
p
< 0.05). In the absorption stage, GGO plus consolidation (9.1%) sharply decreased (
p
< 0.05).
Conclusion
CT imaging of COVID-19 pneumonia showed a predominantly peripheral, middle and lower, and posterior distribution. The early rapid progressive stage is 1~7 days from symptom onset, the advanced stage with peak levels of abnormalities on CT is 8~14 days, and the abnormalities started to improve after 14 days.
Key Points
• The course of COVID-19 pneumonia consists of three stages: 1~7 days is the early rapid progressive stage, 8~14 days is the advanced stage, and after 14 days, the abnormalities started to decrease.
• In the early rapid progressive stage, GGO plus a reticular pattern, GGO plus consolidation, and GGO were all common signs; in the advanced stage, signs of progression and absorption coexisted; lung abnormalities showed an asynchronous process with parts with absorption and parts progressing.
• Lung abnormalities mainly showed predominantly peripheral, middle, and lower distribution.
Wood veneer defect detection plays a vital role in the wood veneer production industry. Studies on wood veneer defect detection usually focused on detection accuracy for industrial applications but ...ignored algorithm execution speed; thus, their methods do not meet the required speed of online detection. In this paper, a new detection method is proposed that achieves high accuracy and a suitable speed for online production. Firstly, 2838 wood veneer images were collected using data collection equipment developed in the laboratory and labeled by experienced workers from a wood company. Then, an integrated model, glance multiple channel mask region convolution neural network (R-CNN), was constructed to detect wood veneer defects, which included a glance network and a multiple channel mask R-CNN. Neural network architect search technology was used to automatically construct the glance network with the lowest number of floating-point operations to pick out potential defect images out of numerous original wood veneer images. A genetic algorithm was used to merge the intermediate features extracted by the glance network. Multi-Channel Mask R-CNN was then used to classify and locate the defects. The experimental results show that the proposed method achieves a 98.70% overall classification accuracy and a 95.31% mean average precision, and only 2.5 s was needed to detect a batch of 50 standard images and 50 defective images. Compared with other wood veneer defect detection methods, the proposed method is more accurate and faster.
Abstract
Deep learning algorithms trained on instances that violate the assumption of being independent and identically distributed (i.i.d.) are known to experience destructive interference, a ...phenomenon characterized by a degradation in performance. Such a violation, however, is ubiquitous in clinical settings where data are streamed temporally from different clinical sites and from a multitude of physiological sensors. To mitigate this interference, we propose a continual learning strategy, entitled CLOPS, that employs a replay buffer. To guide the storage of instances into the buffer, we propose end-to-end trainable parameters, termed task-instance parameters, that quantify the difficulty with which data points are classified by a deep-learning system. We validate the interpretation of these parameters via clinical domain knowledge. To replay instances from the buffer, we exploit uncertainty-based acquisition functions. In three of the four continual learning scenarios, reflecting transitions across diseases, time, data modalities, and healthcare institutions, we show that CLOPS outperforms the state-of-the-art methods, GEM
1
and MIR
2
. We also conduct extensive ablation studies to demonstrate the necessity of the various components of our proposed strategy. Our framework has the potential to pave the way for diagnostic systems that remain robust over time.
Melatonin, an indoleamine widely found in animals and plants, is considered as a candidate phytohormone that affects responses to a variety of biotic and abiotic stresses. In plants, melatonin has a ...similar action to that of the auxin indole-3-acetic acid (IAA), and IAA and melatonin have the same biosynthetic precursor, tryptophan. Salt stress results in the rapid accumulation of melatonin in plants. Melatonin enhances plant resistance to salt stress in two ways: one is via direct pathways, such as the direct clearance of reactive oxygen species; the other is via an indirect pathway by enhancing antioxidant enzyme activity, photosynthetic efficiency, and metabolite content, and by regulating transcription factors associated with stress. In addition, melatonin can affect the performance of plants by affecting the expression of genes. Interestingly, other precursors and metabolite molecules associated with melatonin can also increase the tolerance of plants to salt stress. This paper explores the mechanisms by which melatonin alleviates salt stress by its actions on antioxidants, photosynthesis, ion regulation, and stress signaling.
The low yield of anaerobic ammonium oxidation (anammox) biomass has attracted great attention because of its difficulty to be abundantly enriched. Patterns of substrate supply greatly influence ...microbial metabolism and behavior. The present study proposed that low nitrogen strength was beneficial to anammox biomass yield and nitrogen removal when comparing a membrane bioreactor (MBR) operated at low nitrogen strength with short hydraulic retention time (HRT) (R-low; influent: fixed at 100 mg-N L−1) and one operated at high nitrogen strength with long HRT (R-stepwise; influent: 100-700 mg-N L−1). Different nitrite concentrations in the two MBRs would indicate discrepant environments, and inevitably resulted in the discrepant microbial responses for anammox community. In particular, we found that at low nitrogen strength, increased activities of purine and pyrimidine metabolism pathways provided more abundant nucleic acids for bacterial proliferation. More active reaction of lipid and protein synthesis favored the synthesis of cellular structure. Importantly, the metabolism of cheaper amino acids was more active under low nitrogen strength, which was coupled with higher metabolic flux and potentially more active exchange of costly amino acids as public goods. In this way, more energy could be saved and applied to biomass yield. Higher active bacterial diversity and more positive interactions among bacterial species in R-low further favored biomass yield and nitrogen removal. The present study highlighted the significant effect of substrate supply patterns on anammox, which is meaningful to overcome the current bottleneck of deficient anammox biomass for application in wastewater treatment.
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•Low nitrogen strength was beneficial to anammox biomass yield and nitrogen removal.•Discrepant microbial responses were discussed under different nitrogen strength.•More active reactions of nucleic acids, lipid, and protein synthesis at low nitrogen strength.•More interactions at low nitrogen strength favored biomass yield and nitrogen removal.
Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in childhood. Exploring the risk factors for ADHD is helpful in preventing ADHD.
To explore the association ...between maternal smoking during pregnancy and the occurrence of ADHD in offspring.
PubMed, Embase, and Cochrane Library were searched from inception to May 2017 for studies.
Cohort or case-control studies in which the association between maternal smoking and ADHD in offspring were investigated were eligible if they included odds ratios (ORs), hazard ratios, or risk ratios and 95% confidence intervals (CIs).
Two investigators independently extracted data on definition of exposure and outcome, number of cases and total sample population, and potential confounders adjusted. Any dose-relationship data for smoking and ADHD risk were also extracted.
Fifteen cohort studies and 5 case-control studies with 50 044 cases and 2 998 059 participants were included. Smoking during pregnancy increased the risk of offspring ADHD (OR: 1.60; 95% CI: 1.45-1.76). The risk of ADHD was greater for children whose mothers were heavy smokers (OR: 1.75; 95% CI: 1.51-2.02) than for those mothers were light smokers (OR: 1.54; 95% CI: 1.40-1.70).
The limitations of our study included different assessment tools of ADHD and a lack of objective biological measures for maternal smoking.
With our meta-analysis, we provide evidence for an association between maternal smoking and offspring ADHD but do not solve the causality issues concerning potential confounding by other risk factors. More high-quality studies are needed to establish whether the association with smoking is causal.
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