Publications by authors named "Chunjie Wang"

76 Publications

Alterations of regional spontaneous brain activities in anxiety disorders: A meta-analysis.

J Affect Disord 2021 Sep 25;296:233-240. Epub 2021 Sep 25.

School of Teacher Education, Zhejiang Normal University, Jinhua, China; Key Laboratory of Intelligent Education Technology and Application of Zhejiang Province, Zhejiang Normal University, Jinhua, China. Electronic address:

Background: Recent resting-state functional magnetic resonance imaging studies have provided strong evidence of abnormal regional spontaneous brain activities among anxiety-disordered patients. However, the evidence has been divergent and inconclusive. Therefore, it is necessary to perform a meta-analysis identifying a common pattern of altered regional spontaneous brain activity for anxiety disorders.

Method: Corresponding research of anxiety disorders, namely, whole-brain rs-fMRI studies that measured differences in regional homogeneity, amplitude of low-frequency fluctuations, or fractional amplitude of low-frequency fluctuations, were analyzed in this study. Overall, seven studies with 235 anxiety-disordered patients and 241 healthy controls were ultimately included in the meta-analysis. The meta-analysis was processed by seed-based d mapping.

Results: Compared with healthy controls, patients with anxiety disorders showed significantly decreased regional spontaneous brain activities in the right putamen, the right orbital inferior frontal gyrus, and the right temporal pole. No increases in regional spontaneous brain activities were detected in patients relative to the controls.

Limitation: Limited number of available studies, only Asian samples, and insufficient information of sample characteristics.

Conclusion: The present study suggests that anxiety disorders are associated with aberrant regional brain activity in areas connected with emotion processing, which extends our understanding of anxiety disorders' pathophysiology.
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http://dx.doi.org/10.1016/j.jad.2021.09.062DOI Listing
September 2021

Abnormal Brain Activation During Verbal Memory Encoding in Postacute Anti-N-Methyl-d-Aspartate Receptor Encephalitis.

Brain Connect 2021 Sep 24. Epub 2021 Sep 24.

Department of Neurology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.

Patients with postacute anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis are often left with permanent memory impairments. Given that NMDA receptors are essential to memory encoding, and encoding processes have been suggested to contribute to the success of memory retrieval, we investigate whether postacute anti-NMDA receptor encephalitis leads to abnormal brain activation during verbal memory encoding and its potential effects on subsequent memory retrieval performance. To address this issue, this study recruited 21 adult patients with anti-NMDA receptor encephalitis past the acute stage and 22 healthy controls (HCs). Functional magnetic resonance imaging (fMRI) data were collected when they completed an episodic memory task. At the neural level, the patients showed higher brain activation than the HCs in the bilateral hippocampus/parahippocampus (HG/PHG), right superior temporal gyrus (STG), and right thalamus during memory encoding. At the behavioral level, the patients showed worse memory retrieval performance than the HCs. Importantly, greater brain activation in the left HG/PHG during memory encoding was significantly associated with worse memory retrieval performance among the patients. Our findings indicate that postacute anti-NMDA receptor encephalitis is likely related to altered brain activation during memory encoding. Particularly, less memory retrieval performance often observed in patients with postacute anti-NMDA receptor encephalitis may result from abnormal activation in HG during encoding. These observations may enhance our understanding of NMDA receptor dysfunction in the human brain. Impact statement Patients with anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis are often left with permanent memory impairments. In this study, brain activation during verbal memory encoding and its potential effects on subsequent memory retrieval performance are addressed using 21 adult patients with postacute anti-NMDA receptor encephalitis and 22 healthy controls. Greater brain activation in the left hippocampus/parahippocampus during memory encoding was significantly associated with worse memory retrieval performance among the patients. These observations enhance our understanding of NMDA receptor dysfunction in the human brain.
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http://dx.doi.org/10.1089/brain.2021.0046DOI Listing
September 2021

A Cytoplasm-Enriched circRNA circ-MYBL2 is Downregulated in Non-Small Cell Lung Cancer and Sponges Oncogenic miR-28 to Regulate Cancer Cell Proliferation and Apoptosis.

Cancer Manag Res 2021 16;13:6499-6506. Epub 2021 Aug 16.

Department of General Practice, Dushu Lake Hospital Affiliated to Soochow University, Suzhou, 215000, People's Republic of China.

Background: Recent studies have reported different roles of circRNA circ-MYBL2 in different cancers. However, the involvement of circ-MYBL2 in non-small cell lung cancer (NSCLC) is unknown. This study was carried out to explore the role of circ-MYBL2 in NSCLC.

Methods: The expression of circ-MYBL2 and miR-28 was detected by RT-qPCR. A 5-year follow-up study was performed for survival analysis. Nuclear fractionation assay was used for subcellular localization analysis. RNA pull-down assay was performed to detect the interaction between circ-MYBL2 and miR-28. The role of circ-MYBL2 and miR-28 in regulating the expression of each other was evaluated by overexpression assay. BrdU incorporation assay and cell apoptosis assay were performed to investigate the role of circ-MYBL2 and miR-28 in cell proliferation and apoptosis.

Results: NSCLC tissues exhibited significantly higher expression levels of miR-28 and lower expression levels of circ-MYBL2. Close correlations between circ-MYBL2 and miR-28 and patients' survival were observed. Circ-MYBL2, which was found to be mainly enriched in cytoplasm, directly interacted with miR-28. Although circ-MYBL2 and miR-28 showed no regulatory role in the expression of each other, circ-MYBL2 suppressed the effects of miR-28 on cell proliferation and apoptosis.

Conclusion: Circ-MYBL2 is enriched in cytoplasm, and it sponges oncogenic miR-28 to suppress cancer cell proliferation in NSCLC and promote cell apoptosis.
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http://dx.doi.org/10.2147/CMAR.S309924DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8379391PMC
August 2021

Effects of dietary forage to concentrate ratio on nutrient digestibility, ruminal fermentation and rumen bacterial composition in Angus cows.

Sci Rep 2021 08 23;11(1):17023. Epub 2021 Aug 23.

College of Animal Science, Inner Mongolia Agricultural University, Hohhot, 010018, China.

This study evaluated effects of dietary forage to concentrate ratio (F:C) on the body weight, digestibility, ruminal fermentation and rumen bacterial composition in Angus cows. Three diets with different F:C (LCD: 65:35, MCD:50:50, and HCD: 35:65) were fed to ninety Angus cows (3.2 ± 0.18 years old, 387.2 ± 22.6 kg). The average daily gain (ADG) and ammonia nitrogen concentration increased (P = 0.039 and P = 0.026, respectively), whereas the acetate to propionate ratio (P = 0.027) and the neutral detergent fiber (NDF) digestibility decreased with increasing concentrate level. The acetate concentration and ruminal pH (P = 0.033 and P = 0.029, respectively) decreased by feeding HCD diet. Serum amyloid A (SAA), C-reactive protein (CRP), haptoglobin (Hp) and lipopolysaccharide binding protein (LBP) increased under the HCD. The relative abundances of Bacteroidetes, Fibrobacterota, Prevotella and Prevotellaceae UCG-003 decreased, whereas the relative abundances of Ruminococcaceae NK4A214 group, Saccharofermentans and Spirochaetota increased with increasing dietary concentrate level. Our study provides a better understanding of rumen fermentation parameters and microbiota under a wide range of dietary F:C ratios, supporting the potential dietary manipulation of microbes, which could enhance feed digestibility associated with cow rearing.
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http://dx.doi.org/10.1038/s41598-021-96580-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8382751PMC
August 2021

Individualized video recommendation modulates functional connectivity between large scale networks.

Hum Brain Mapp 2021 Nov 6;42(16):5288-5299. Epub 2021 Aug 6.

Department of Psychology and Behavioral Sciences, Zhejiang University, Hangzhou, China.

With the emergence of AI-powered recommender systems and their extensive use in the video streaming service, questions and concerns also arise. Why can recommended video content continuously capture users' attention? What is the impact of long-term exposure to personalized video content on one's behaviors and brain functions? To address these questions, we designed an fMRI experiment presenting participants with personally recommended videos and generally recommended ones. To examine how large-scale networks were modulated by personalized video content, graph theory analysis was applied to investigate the interaction between seven networks, including the ventral and dorsal attention networks (VAN, DAN), frontal-parietal network (FPN), salience network (SN), and three subnetworks of default mode network (dorsal medial prefrontal (dMPFC), Core, and medial temporal lobe (MTL)). Our results showed that viewing nonpersonalized video content mainly enhanced the connectivity in the DAN-FPN-Core pathway, whereas viewing personalized ones increased not only the connectivity in this pathway but also the DAN-VAN-dMPFC pathway. In addition, both personalized and nonpersonalized short videos decreased the couplings between SN and VAN as well as between two DMN subsystems, Core and MTL. Collectively, these findings uncovered distinct patterns of network interactions in response to short videos and provided insights into potential neural mechanisms by which human behaviors are biased by personally recommended content.
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http://dx.doi.org/10.1002/hbm.25616DOI Listing
November 2021

New methods for the additive hazards model with the informatively interval-censored failure time data.

Biom J 2021 Oct 3;63(7):1507-1525. Epub 2021 Jul 3.

Department of Statistics, University of Missouri, Columbia, MO, USA.

The additive hazards model is one of the most commonly used models for regression analysis of failure time data and many inference procedures have been developed for it under various situations. In particular, Wang et al. (2018a, Computational Statistics and Data Analysis, 125, 1-9) discussed the situation where one observes informatively interval-censored data and proposed a likelihood estimation approach. However , it involves estimation of the unknown baseline cumulative hazard function and thus may be time-consuming . Corresponding to this, we propose two new procedures, an estimating equation-based one and an empirical likelihood-based one, and both do not need estimation of the cumulative hazard function and can be easily implemented. The asymptotic properties of the proposed methods are established and an extensive simulation study suggests that they work well in practical situations. An application is also provided.
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http://dx.doi.org/10.1002/bimj.202000288DOI Listing
October 2021

Comparative Analysis of Fecal Microbiota of Grazing Mongolian Cattle from Different Regions in Inner Mongolia, China.

Animals (Basel) 2021 Jun 29;11(7). Epub 2021 Jun 29.

College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, China.

Mongolian cattle from China have strong adaptability and disease resistance. We aimed to compare the gut microbiota community structure and diversity in grazing Mongolian cattle from different regions in Inner Mongolia and to elucidate the influence of geographical factors on the intestinal microbial community structure. We used high throughput 16S rRNA sequencing to analyze the fecal microbial community and diversity in samples from 60 grazing Mongolian cattle from Hulunbuir Grassland, Xilingol Grassland, and Alxa Desert. A total of 2,720,545 high-quality reads and sequences that were 1,117,505,301 bp long were obtained. Alpha diversity among the three groups showed that the gut microbial diversity in Mongolian cattle in the grasslands was significantly higher than that in the desert. The dominant phyla were and , whereas presented the highest abundance in the gut of cattle in the Alxa Desert. The gut bacterial communities in cattle from the grasslands versus the Alxa Desert were distinctive, and those from the grasslands were closely clustered. Community composition analysis revealed significant differences in species diversity and richness. Overall, the composition of the gut microbiota in Mongolian cattle is affected by geographical factors. Gut microbiota may play important roles in the geographical adaptations of Mongolian cattle.
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http://dx.doi.org/10.3390/ani11071938DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8300212PMC
June 2021

A preliminary study using spinal MRI-based radiomics to predict high-risk cytogenetic abnormalities in multiple myeloma.

Radiol Med 2021 Sep 22;126(9):1226-1235. Epub 2021 Jun 22.

Department of Radiology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, People's Republic of China.

Objectives: We aimed to investigate the feasibility of predicting high-risk cytogenetic abnormalities (HRCAs) in patients with multiple myeloma (MM) using a spinal MRI-based radiomics method.

Materials And Methods: In this retrospective study, we analyzed the radiomic features of 248 lesions (HRCA [n = 111] and non-HRCA [n = 137]) using T1WI, T2WI, and fat suppression T2WI. To construct the radiomics model, the top nine most frequent radiomic features were selected using logistic regression (LR) machine-learning processes. A combined LR model incorporating radiomic features and basic clinical characteristics (age and sex) was also built. Fivefold external cross-validation was performed, and a comparative analysis of 10 random fivefold cross-validation sets was used to verify result stability. Model performance was compared by plotting receiver operating characteristic curves and the area under the curve (AUC).

Results: Comparable AUC values were observed between the radiomics model and the combined model in validation cohorts (AUC: 0.863 vs. 0.870, respectively, p = 0.206). The radiomics model had an AUC of 0.863, with a sensitivity of 0.789, a specificity of 0.787, a positive predictive value of 0.753, a negative predictive value of 0.824, and an accuracy of 0.788 in the validation cohort, which were comparable with the performance in the training cohorts.

Conclusions: Radiomic features of routine spinal MRI reflect differences between HRCAs and non-HRCAs in patients with MM. This MRI-based radiomics model might be a useful and independent tool to predict HRCAs in patients MM.
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http://dx.doi.org/10.1007/s11547-021-01388-yDOI Listing
September 2021

The Synthesis of Planar Four-Bar Linkage for Mixed Motion and Function Generation.

Sensors (Basel) 2021 May 18;21(10). Epub 2021 May 18.

School of Mechanical Engineering and Automation, Beihang University, Beijing 100191, China.

The synthesis of four-bar linkage has been extensively researched, but for a long time, the problem of motion generation, path generation, and function generation have been studied separately, and their integration has not drawn much attention. This paper presents a numerical synthesis procedure for four-bar linkage that combines motion generation and function generation. The procedure is divided into two categories which are named as dependent combination and independent combination. Five feasible cases for dependent combination and two feasible cases for independent combination are analyzed. For each of feasible combinations, fully constrained vector loop equations of four-bar linkage are formulated in a complex plane. We present numerical examples to illustrate the synthesis procedure and determine the defect-free four-bar linkages.
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http://dx.doi.org/10.3390/s21103504DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8157276PMC
May 2021

Proactive Control Mediates the Relationship Between Working Memory and Math Ability in Early Childhood.

Front Psychol 2021 7;12:611429. Epub 2021 May 7.

Department of Psychology, Suzhou University of Science and Technology, Suzhou, China.

Based on the dual mechanisms of control (DMC) theory, there are two distinct mechanisms of cognitive control, proactive and reactive control. Importantly, accumulating evidence indicates that there is a developmental shift from predominantly using reactive control to proactive control during childhood, and the engagement of proactive control emerges as early as 5-7 years old. However, less is known about whether and how proactive control at this early age stage is associated with children's other cognitive abilities such as working memory and math ability. To address this issue, the current study recruited 98 Chinese children under 5-7 years old. Among them, a total of 81 children (mean age = 6.29 years) contributed useable data for the assessments of cognitive control, working memory, and math ability. The results revealed that children at this age period predominantly employed a pattern of proactive control during an AX-Continuous Performance Task (AX-CPT). Moreover, the proactive control index estimated by this task was positively associated with both working memory and math performance. Further regression analysis showed that proactive control accounted for significant additional variance in predicting math performance after controlling for working memory. Most interestingly, mediation analysis showed that proactive control significantly mediated the association between working memory and math performance. This suggests that as working memory increases so does proactive control, which may in turn improve math ability in early childhood. Our findings may have important implications for educational practice.
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http://dx.doi.org/10.3389/fpsyg.2021.611429DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8137833PMC
May 2021

Applying the Carolina care model to improve nurses' humanistic care abilities.

Am J Transl Res 2021 15;13(4):3591-3599. Epub 2021 Apr 15.

Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University Chongqing, China.

Purpose: To study the application of the Carolina Care Model to improve nurses' humanistic care abilities in the Department of Obstetrics and Gynecology.

Methods: From December 2019 to April 2020, 40 nursing staff and 80 patients in the Department of Obstetrics and Gynecology in our hospital were recruited as the study cohort and randomly placed in an intervention group or a control group. The intervention group underwent the Carolina Care Model to complete the clinical nursing work. The control group underwent hospital routines to complete clinical nursing work.

Results: After the training, the humanistic care ability scores and the scores of various dimensions in the intervention group were significantly higher than the scores in the control group (P<0.05). The patient care perception scores in the intervention group were higher than they were in the control group (P<0.05). The patients' nursing satisfaction scores in the intervention group were significantly higher than they were in the control group (P<0.05).

Conclusion: Carrying out a humanistic care nursing practice based on the Carolina Care Model can improve the humanistic care abilities of the nurses in the Department of Obstetrics and Gynecology, patient care perception and satisfaction, and the quality of the nursing service.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8129219PMC
April 2021

Influence of humanistic care based on Carolina care model for ovarian cancer patients on postoperative recovery and quality of life.

Am J Transl Res 2021 15;13(4):3390-3399. Epub 2021 Apr 15.

Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University Chongqing, China.

Objective: Our aim was to explore the influence of humanistic care based on Carolina care model on postoperative recovery and quality of life in patients with ovarian cancer (OC).

Methods: In this prospective study, we selected 85 OC patients and randomly divided them into the Carolina group (n = 43) given humanistic care based on Carolina care model and the control group (n = 42) given routine nursing intervention. The postoperative recovery and Functional Assessment of Cancer Therapy-Ovary Cancer (FACT-O) scores were compared between the two groups.

Results: After intervention, the time of first flatus and defecation after surgery, the time of first ambulation and the length of average postoperative hospital stay were much shorter, and the pain score, total complication rate, self-rating anxiety scale and self-rating depression scale scores as well as Cortisol, C-reactive protein and fasting blood glucose levels at 48 hours postoperatively were significantly lower in the Carolina group than in the control group. The nursing satisfaction in the Carolina group was markedly higher than that in the control group (97.67% vs. 78.57%, P<0.01). After 3 months of follow-up, the Carolina group showed higher dimension scores of FACT-O than the control group (all P<0.001).

Conclusion: Humanistic nursing care based on Carolina care model can significantly ameliorate the recovery of OC patients, reduce the physical and psychologic stress response, and effectively enhance the nursing satisfaction and quality of life.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8129217PMC
April 2021

Prediction of High-Risk Cytogenetic Status in Multiple Myeloma Based on Magnetic Resonance Imaging: Utility of Radiomics and Comparison of Machine Learning Methods.

J Magn Reson Imaging 2021 10 12;54(4):1303-1311. Epub 2021 May 12.

Department of Radiology, Peking University Third Hospital, Haidian District, Beijing, People's Republic of China.

Background: Radiomics has shown promising results in the diagnosis, efficacy, and prognostic assessments of multiple myeloma (MM). However, little evidence exists on the utility of radiomics in predicting a high-risk cytogenetic (HRC) status in MM.

Purpose: To develop and test a magnetic resonance imaging (MRI)-based radiomics model for predicting an HRC status in MM patients.

Study Type: Retrospective.

Population: Eighty-nine MM patients (HRC [n: 37] and non-HRC [n: 52]).

Field Strength/sequence: A 3.0 T; fast spin-echo (FSE): T1-weighted image (T1WI) and fat-suppression T2WI (FS-T2WI).

Assessment: Overall, 1409 radiomics features were extracted from each volume of interest drawn by radiologists. Three sequential feature selection steps-variance threshold, SelectKBest, and least absolute shrinkage selection operator-were repeated 10 times with 5-fold cross-validation. Radiomics models were constructed with the top three frequency features of T WI/T WI/two-sequence MRI (T WI and FS-T WI). Radiomics models, clinical data (age and visually assessed MRI pattern), or radiomics combined with clinical data were used with six classifiers to distinguish between HRC and non-HRC statuses. Six classifiers used were support vector machine, random forest, logistic regression (LR), decision tree, k-nearest neighbor, and XGBoost. Model performance was evaluated with area under the curve (AUC) values.

Statistical Tests: Mann-Whitney U-test, Chi-squared test, Z test, and DeLong method.

Results: The LR classifier performed better than the other classifiers based on different data (AUC: 0.65-0.82; P < 0.05). The two-sequence MRI models performed better than the other data models using different classifiers (AUC: 0.68-0.82; P < 0.05). Thus, the LR two-sequence model yielded the best performance (AUC: 0.82 ± 0.02; sensitivity: 84.1%; specificity: 68.1%; accuracy: 74.7%; P < 0.05).

Conclusion: The LR-based machine learning method appears superior to other classifier methods for assessing HRC in MM. Radiomics features based on two-sequence MRI showed good performance in differentiating HRC and non-HRC statuses in MM.

Evidence Level: 3 TECHNICAL EFFICACY: Stage 2.
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http://dx.doi.org/10.1002/jmri.27637DOI Listing
October 2021

Regression analysis of current status data with latent variables.

Lifetime Data Anal 2021 07 24;27(3):413-436. Epub 2021 Apr 24.

Department of Statistics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.

Current status data occur in many fields including demographical, epidemiological, financial, medical, and sociological studies. We consider the regression analysis of current status data with latent variables. The proposed model consists of a factor analytic model for characterizing latent variables through their multiple surrogates and an additive hazard model for examining potential covariate effects on the hazards of interest in the presence of current status data. We develop a borrow-strength estimation procedure that incorporates the expectation-maximization algorithm and correlated estimating equations. The consistency and asymptotic normality of the proposed estimators are established. A simulation study is conducted to evaluate the finite sample performance of the proposed method. A real-life study on the chronic kidney disease of type 2 diabetic patients is presented.
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http://dx.doi.org/10.1007/s10985-021-09521-9DOI Listing
July 2021

Adaptive Reconfiguration of Intrinsic Community Structure in Children with 5-Year Abacus Training.

Cereb Cortex 2021 05;31(6):3122-3135

Bio-X Laboratory, Interdisciplinary Center for Quantum Information, State Key Laboratory of Modern Optical Instrumentation, and Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, China.

Human learning can be understood as a network phenomenon, underpinned by the adaptive reconfiguration of modular organization. However, the plasticity of community structure (CS) in resting-state network induced by cognitive intervention has never been investigated. Here, we explored the individual difference of intrinsic CS between children with 5-year abacus-based mental calculation (AMC) training (35 subjects) and their peers without prior experience in AMC (31 subjects). Using permutation-based analysis between subjects in the two groups, we found the significant alteration of intrinsic CS, with training-attenuated individual difference. The alteration of CS focused on selective subsets of cortical regions ("core areas"), predominantly affiliated to the visual, somatomotor, and default-mode subsystems. These subsystems exhibited training-promoted cohesion with attenuated interaction between them, from the perspective of individuals' CS. Moreover, the cohesion of visual network could predict training-improved math ability in the AMC group, but not in the control group. Finally, the whole network displayed enhanced segregation in the AMC group, including higher modularity index, more provincial hubs, lower participation coefficient, and fewer between-module links, largely due to the segregation of "core areas." Collectively, our findings suggested that the intrinsic CS could get reconfigured toward more localized processing and segregated architecture after long-term cognitive training.
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http://dx.doi.org/10.1093/cercor/bhab010DOI Listing
May 2021

Persistent inflammation worsens short-term outcomes in massive stroke patients.

BMC Neurol 2021 Feb 10;21(1):62. Epub 2021 Feb 10.

Department of Neurology, Shanghai Fifth People's Hospital, Fudan University, No. 801, Heqing Road, Shanghai, 200240, China.

Background: Persistent inflammation is an important driver of disease progression and affects prognosis. Some indicators of inflammation predict short-term outcomes. The relationship between prognosis, especially mortality, and persistent inflammation in massive stroke has not been studied, and this has been the subject of our research.

Methods: From April 1, 2017 to February 1, 2020, consecutive patients were prospectively enrolled. Clinical data, laboratory data, imaging data and follow-up infections morbidity were compared between 2 groups according to modified Rankin scale (mRS) scores (mRS < 3 and ≥ 3) at 1 month. The binomial logistic analysis was used to determine independent factors of 1-month prognosis. Short-term functional outcome, mortality and infection rates in massive stroke with and without persistent inflammation were compared.

Results: One hundred thirty-nine patients with massive stroke were included from 800 patients. We found that admission blood glucose levels (p = 0.005), proportions of cerebral hemispheric (p = 0.001), posterior circulatory (p = 0.035), and lacunar (p = 0.022) ischemia were higher in poor outcome patients; neutrophil-to-lymphocyte ratio (odd ratio = 1.87, 95%CI 1.14-3.07, p = 0.013) and blood glucose concentrations (odd ratio = 1.34, 95%CI 1.01-1.79, p = 0.043) can independently predict the short-term prognosis in massive stroke patients. We also found that the incidence of pulmonary infection (p = 0.009), one-month mortality (p = 0.003) and adverse outcomes (p = 0.0005) were higher in patients with persistent inflammation.

Conclusions: This study suggested that persistent inflammation is associated with poor prognosis, 1-month mortality and the occurrence of in-hospital pulmonary infection and that higher baseline inflammation level predicts short-term poor outcomes in massive stroke.
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http://dx.doi.org/10.1186/s12883-021-02097-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7874622PMC
February 2021

Planular-vertical distribution and pollution characteristics of cropland soil Hg and the estimated soil-air exchange fluxes of gaseous Hg over croplands in northern China.

Environ Res 2021 04 30;195:110810. Epub 2021 Jan 30.

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No. 18 Shuangqing Road, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:

As an important reservoir of mercury (Hg), cropland play an important role in the Hg cycle, but it was poorly understood in northern China. The major objectives of this study are to ascertain the distribution characteristics of soil Hg and then assess its pollution level and potential risk, and further evaluate the role of cropland in northern China in the global soil-air exchange of Hg based on the simulation experiments and regional survey. The average Hg concentration in surface soils of the 30 sites in northern China was 116.1 ± 135.8 ng g, which was significantly higher than background values. The surface soils show a significant spatial heterogeneity in Hg concentration, and the Hg levels near provincial capitals were higher than those at corresponding prefecture-level cities, revealing that the soil Hg levels were closely associated with the local industrial and economic development. Profile data shows that topsoil Hg concentration was significantly higher than those in deeper layers at most of sites, indicating the more serious pollution situation in recent years. Generally, the higher the surface soil Hg concentration, the more obvious this top-bottom decreasing trend. The planular-vertical distribution patterns of TOM share similar trends as those of soil Hg concentration, indicating Hg concentration was closely associated with TOM content. Statistical results show that the mean CF, E, and I values were 4.0 ± 5.0, 161 ± 198, 0.76 ± 1.34, respectively, and more than two thirds of sampling sites were moderately and considerably polluted. The mean annual accumulative flux of Hg in the northern China was 20.9 ± 43.8 μg m yr, and the total net emission fluxes of Hg from the croplands in six provinces were 8.37 ton yr. This indicates that although the cropland occasionally acts as a sink, it represents an important natural source of atmospheric Hg as a whole.
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http://dx.doi.org/10.1016/j.envres.2021.110810DOI Listing
April 2021

An additive hazards cure model with informative interval censoring.

Lifetime Data Anal 2021 04 22;27(2):244-268. Epub 2021 Jan 22.

Center for Applied Statistical Research, School of Mathematics, Jilin University, Changchun, 130012, China.

The existence of a cured subgroup happens quite often in survival studies and many authors considered this under various situations (Farewell in Biometrics 38:1041-1046, 1982; Kuk and Chen in Biometrika 79:531-541, 1992; Lam and Xue in Biometrika 92:573-586, 2005; Zhou et al. in J Comput Graph Stat 27:48-58, 2018). In this paper, we discuss the situation where only interval-censored data are available and furthermore, the censoring may be informative, for which there does not seem to exist an established estimation procedure. For the analysis, we present a three component model consisting of a logistic model for describing the cure rate, an additive hazards model for the failure time of interest and a nonhomogeneous Poisson model for the observation process. For estimation, we propose a sieve maximum likelihood estimation procedure and the asymptotic properties of the resulting estimators are established. Furthermore, an EM algorithm is developed for the implementation of the proposed estimation approach, and extensive simulation studies are conducted and suggest that the proposed method works well for practical situations. Also the approach is applied to a cardiac allograft vasculopathy study that motivated this investigation.
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http://dx.doi.org/10.1007/s10985-021-09515-7DOI Listing
April 2021

A Review of the Effects of Abacus Training on Cognitive Functions and Neural Systems in Humans.

Authors:
Chunjie Wang

Front Neurosci 2020 2;14:913. Epub 2020 Sep 2.

Institute of Brain Science and Department of Psychology, School of Education, Hangzhou Normal University, Hangzhou, China.

Abacus, which represents numbers via a visuospatial format, is a traditional device to facilitate arithmetic operations. Skilled abacus users, who have acquired the ability of abacus-based mental calculation (AMC), can perform fast and accurate calculations by manipulating an imaginary abacus in mind. Due to this extraordinary calculation ability in AMC users, there is an expanding literature investigating the effects of AMC training on cognition and brain systems. This review study aims to provide an updated overview of important findings in this fast-growing research field. Here, findings from previous behavioral and neuroimaging studies about AMC experts as well as children and adults receiving AMC training are reviewed and discussed. Taken together, our review of the existing literature suggests that AMC training has the potential to enhance various cognitive skills including mathematics, working memory and numerical magnitude processing. Besides, the training can result in functional and anatomical neural changes that are largely located within the frontal-parietal and occipital-temporal brain regions. Some of the neural changes can explain the training-induced cognitive enhancements. Still, caution is needed when extend the conclusions to a more general situation. Implications for future research are provided.
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http://dx.doi.org/10.3389/fnins.2020.00913DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7492585PMC
September 2020

Langerhans Cell Histiocytosis Associated With Renal Cell Carcinoma Is a Neoplastic Process: Clinicopathologic and Molecular Study of 7 Cases.

Am J Surg Pathol 2020 12;44(12):1658-1665

Institute of Pathology, Friedrich-Alexander-University Erlangen-Nuremberg, University Hospital of Erlangen, Erlangen.

Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder composed of Langerhans cells admixed with reactive mononuclear and granulocytic cells, associated with prominent eosinophils. LCH is considered a neoplasm, driven in most cases by oncogenic RAS/RAF/MEK/ERK pathway mutations. The disease predominantly affects children. Urinary system involvement has rarely been reported in a multisystem disease setting. We describe 7 patients who presented with LCH occurring within (6 cases) or after (1 case) a resected clear cell (n=6) or clear cell papillary (n=1) renal cell carcinoma (RCC), identified prospectively in our routine and consultation files (2012 to 2019). The patients included 5 women and 2 men, with a median age of 54 years (range, 39 to 73 y), none with a history of LCH or LCH manifestations before the time of RCC diagnosis. The median size of the RCC was 3.5 cm (range, 1.8 to 8.3 cm). Treatment included partial (5 cases), or radical (2 cases) nephrectomy. All RCCs on gross examination showed at least focal cystic changes and were low grade (World Health Organization [WHO]/International Society of Urologic Pathologists [ISUP] grade 1 to 2). The LCH foci were detected as incidental histological finding within the resected RCC in all six cases and they were limited to few high-power fields (<2 mm) in 5 of 6 cases, but in the sixth case, they occupied almost the entire clear cell papillary RCC (2 cm nodule). No LCH manifestations were detected in the normal kidney or in perinephric fat. The seventh patient developed LCH within inguinal deep soft tissue followed by systemic manifestations 6 years after clear cell RCC. Langerhans cell immunophenotype was supported by the reactivity for S-100, CD1a, and langerin and by the negative pankeratin. Successful pyrosequencing of microdissected LCH DNA revealed the V600E BRAF mutation in all 6 cases of LCH within RCC. To our knowledge, only 3 similar cases were published since 1980; the only case tested for BRAF mutation showed wild-type BRAF. This is the first study analyzing the morphologic and genetic features of a cohort of LCH associated with RCC. In our experience, these cases may be underrecognized in practice, or may erroneously be diagnosed as RCC dedifferentiation or high-grade sarcomatoid transformation. Finally, the detection of BRAF mutation further confirms that LCH in this setting is indeed a neoplasm, rather than a reactive lesion.
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http://dx.doi.org/10.1097/PAS.0000000000001562DOI Listing
December 2020

Effects of avitinib on the pharmacokinetics of osimertinib in vitro and in vivo in rats.

Thorac Cancer 2020 10 19;11(10):2775-2781. Epub 2020 Aug 19.

VIP Ward, Suzhou Dushuhu Public Hospital, Dushuhu Public Hospital Affiliated to Soochow University, The First Affiliated Hospital of Soochow University, Dushuhu Branch, Suzhou, Jiangsu, China.

Background: Avitinib is one type of the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) for the treatment of non-small cell lung cancer (NSCLC) with EGFR mutations. The purpose of this study was to investigate the effect of avitinib on the pharmacokinetics of osimertinib, one FDA approved third-generation TIKI, both in vitro and in vivo.

Methods: The in vitro metabolic stability and inhibitory effect of avitinib on osimertinib were assessed with rat liver microsomes (RLM) to determine its IC values. For the in vivo study, 18 Sprague-Dawley rats were randomly divided into three groups: the avitinib multiple dose group (30 mg/kg avitinib once daily for seven days), the avitinib single dose group (PEG200 once daily for six days and a dose of 30 mg/kg avitinib in PEG200 on day 7) and the control group (equal amounts of PEG200 once daily for seven days). Next, all rats were given osimertinib at a dosage of 10 mg/kg. UPLC/MS-MS was used for the determination of the concentration of osimertinib in plasma.

Results: In vitro analysis revealed that the IC value of osimertinib in rat liver microsomes was 27.6 μM. When rats were pretreated with avitinib, the values of AUC and MRT of the osimertinib were increased, and its C and T were significantly extended, whereas the values of CLz/F were significantly decreased (P < 0.05).

Conclusions: Both in vitro and in vivo results demonstrated that a drug-drug interaction between avitinib and osimertinib occurred and more attention should be paid when avitinib and osimertinib are synchronously administered in clinic.

Key Points: SIGNIFICANT FINDINGS OF THE STUDY: Osimertinib is the only market available third-generation EGFR-TKI and it has been reported that some drugs could have drug-drug interactions with it.

What This Study Adds: For the first time, we systematically investigated the effect of avitinib, one newly developed third-generation EGFR-TKI, on the pharmacokinetics of osimertinib both in vitro and in vivo using a rat model.
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http://dx.doi.org/10.1111/1759-7714.13587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7529555PMC
October 2020

Systemic immune-inflammation index (SII) but not platelet-albumin-bilirubin (PALBI) grade is associated with severity of acute ischemic stroke (AIS).

Int J Neurosci 2020 Jun 26:1-6. Epub 2020 Jun 26.

Department of Neurology, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.

Inflammation plays an important role in stroke. Many inflammatory markers in peripheral blood are proved to be associated with stroke severity or prognosis. But few comprehensive models or scales to evaluate the severity of stroke have been reported. Systemic immune-inflammation index (SII) and platelet-albumin-bilirubin (PALBI) grade as new markers of inflammation have shown their positive association with liver cancer. The relation between SII, or PALBI and stroke remains uncertain. To investigate the relationship between SII, PALBI grade and stroke severity. Patients with ischemic stroke with hospital admission <24 h after symptom onset were prospectively included in a stroke registry. Demographic, clinical, and laboratory data were collected immediately after admission in all patients. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity upon admission. Minor stroke was defined as NIHSS score < =5, moderate-to-severe stroke as NIHSS score >5. SII, calculated as platelet × neutrophil/lymphocyte was divided into four groups according to interquartile range: lowest SII (SII < 353.9 × 10/L), low SII (353.9-532.8 × 10/L), high SII (532.8-783.9 × 10/L), and highest SII (>783.9 × 10/L) group. A total of 362 patients with ischemic stroke were included, and between minor and moderate-to-severe stroke significant difference was found in SII ( < 0.0001), NLR ( < 0.0001), and PLR ( = 0.001), respectively. After multivariate regression analyses, SII groups (Odd ratio = 1.351, 95% confidence interval 1.084-1.684,  = 0.007) not PALBI was an independent risk factor for stroke severity. We found that SII but not PALBI, which both are markers of inflammation, was independently associated with stroke severity.
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http://dx.doi.org/10.1080/00207454.2020.1784166DOI Listing
June 2020

Training on Abacus-based Mental Calculation Enhances Resting State Functional Connectivity of Bilateral Superior Parietal Lobules.

Neuroscience 2020 04 27;432:115-125. Epub 2020 Feb 27.

Bio-X Laboratory, Department of Physics, Zhejiang University, Hangzhou 310027, China.

Accumulating evidence indicates a positive effect of abacus-based mental calculation (AMC) training on various cognitive functions including short-term memory (STM). Our previous work has shown AMC training-induced activation changes in the frontal-parietal network (FPN) using task fMRI. However, whether AMC training-induced functional plasticity in the same brain network can be detected at resting state remains unknown. The current study aimed to address this question using resting state functional connectivity in a longitudinal AMC training experiment engaging a training group (18 subjects, age = 21.439 ± 0.565) and a control group (18 subjects, age = 21.113 ± 1.140). Our results revealed that the average functional connectivity strength within the FPN showing task activation changes was significantly enhanced after training in the AMC group, whereas it remained stable in the control group. Further analysis indicated that such connectivity increase in the AMC group was primarily driven by the enhanced coupling of bilateral superior parietal lobules (SPL). In addition, a significant and positive correlation between letter forward memory span and SPL connectivity was found at post-training session in the AMC group. While the weakest quartile of SPL connections ranking by pre-training connectivity strength showed the largest effect of enhancement after training, it was the strongest quartile of SPL connectivity that correlated the most with memory span at post-training session. These findings suggest that AMC training may enhance bilateral SPL functional connectivity, through which AMC training might exert a transfer effect to improve short-term memory capacity.
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http://dx.doi.org/10.1016/j.neuroscience.2020.02.033DOI Listing
April 2020

Characteristics of mercury speciation in seawater and emission flux of gaseous mercury in the Bohai Sea and Yellow Sea.

Environ Res 2020 03 26;182:109092. Epub 2019 Dec 26.

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China. Electronic address:

Four cruises were performed in the Bohai Sea (BS) and Yellow Sea (YS) to ascertain the levels and distributions of gaseous elemental mercury (GEM), dissolved gaseous mercury (DGM), methylmercury (MeHg), and total mercury (THg) during 2012 and 2014. Their concentrations and Hg flux exhibited clear spatial-temporal distributions. The GEM level over the BS in spring (2.71 ± 0.49 ng m) was significantly higher than that in fall (1.98 ± 0.91 ng m). Air masses with elevated GEM mainly originated from northern China. During the two cruises in 2012 over the BS, the mean DGM concentration in spring (35.7 ± 4.6 pg l) was comparable to that in fall (32.4 ± 4.6 pg l). During the spring cruise of 2014, the mean DGM concentration in the BS (52.8 ± 12.5 pg l) was comparable to that in the YS (52.4 ± 14.1 pg l), while during the fall cruise of 2014, it was significantly lower in the BS (26.7 ± 14.4 pg l) than in the YS (57.2 ± 17.9 pg l). DGM represents a small portion of unfiltered THg in the BS (3.95%) and YS (5.12%). The MeHg and MeHg% values were higher in nearshore areas than in open sea, indicating higher productivity in coastal regions. The Hg flux in the YS (4.56 ng m h) was about twice that in the BS. The annual emission Hg fluxes from the BS and YS were 2.71 and 23.68 tons yr, respectively.
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http://dx.doi.org/10.1016/j.envres.2019.109092DOI Listing
March 2020

Amplification of a calcium channel subunit CACNG4 increases breast cancer metastasis.

EBioMedicine 2020 Feb 12;52:102646. Epub 2020 Feb 12.

The Campbell Family for Breast Cancer Research, Princess Margaret Cancer Centre, Toronto, ON M5G 2M9, Canada; Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Medical Biophysics, Faculty of Medicine, University of Toronto, ON M5S 1A1, Canada; Laboratory Medicine Program, Department of Pathology, University Health Network, Toronto General Hospital, 200 Elizabeth Street, 11th floor, Toronto, ON M5G 2C4, Canada. Electronic address:

Background: Previously, we found that amplification of chromosome 17q24.1-24.2 is associated with lymph node metastasis, tumour size, and lymphovascular invasion in invasive ductal carcinoma. A gene within this amplicon, CACNG4, an L-type voltage-gated calcium channel gamma subunit, is elevated in breast cancers with poor prognosis. Calcium homeostasis is achieved by maintaining low intracellular calcium levels. Altering calcium influx/efflux mechanisms allows tumour cells to maintain homeostasis despite high serum calcium levels often associated with advanced cancer (hypercalcemia) and aberrant calcium signaling.

Methods: In vitro 2-D and 3-D assays, and intracellular calcium influx assays were utilized to measure tumourigenic activity in response to altered CANCG4 levels and calcium channel blockers. A chick-CAM model and mouse model for metastasis confirmed these results in vivo.

Findings: CACNG4 alters cell motility in vitro, induces malignant transformation in 3-dimensional culture, and increases lung-specific metastasis in vivo. CACNG4 functions by closing the channel pore, inhibiting calcium influx, and altering calcium signaling events involving key survival and metastatic pathway genes (AKT2, HDAC3, RASA1 and PKCζ).

Interpretation: CACNG4 may promote homeostasis, thus increasing the survival and metastatic ability of tumour cells in breast cancer. Our findings suggest an underlying pathway for tumour growth and dissemination regulated by CACNG4 that is significant with respect to developing treatments that target these channels in tumours with aberrant calcium signaling.

Funding: Canadian Breast Cancer Foundation, Ontario; Canadian Institutes of Health Research.
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http://dx.doi.org/10.1016/j.ebiom.2020.102646DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7016384PMC
February 2020

Curcumin ameliorates Staphylococcus aureus-induced mastitis injury through attenuating TLR2-mediated NF-κB activation.

Microb Pathog 2020 Feb 13;142:104054. Epub 2020 Feb 13.

College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China. Electronic address:

Problem: It has long been known that Staphylococcus aureus (S. aureus, serotype CP8) is associated with clinical mastitis in cows, and recent scientific studies have shown that curcumin (CUR) is effective in anti-inflammatory. However, the mechanism of action of curcumin on S. aureus-induced cows has not been fully understood. Therefore, this study investigated whether curcumin could improve the inflammation response in mice mastitis and to clarify the possible mechanism.

Method: of study: A mouse mastitis model was established. The mice were administered curcumin (125 mg/kg), ciprofloxacin (130 mg/kg, CIP), and water (model group) for 5 days.

Results: CUR and CIP treatment prevented the S. aureus-induced mouse mastitis increase the levels of IL-2, IL-10, and IFN-γ and decrease levels of IL-6, IL-8, and TNF-α. Additionally, RT-PCR results showed that 20 μg/mL curcumin inhibited the mRNA expression of TNF-α, IL-6, IL-1β, TRAF6 and MEKK1 in murine mammary epithelial cells (MMECs). Likewise, Western blotting results showed that CUR inhibited the expression of TRAF6 and MEKK1.

Conclusion: These results indicated that CUR is superior to CIP in the prevention of mastitis, and the mechanism may be that the curative effect of CUR inhibits TLR-2 mediated NF-κB signaling pathway in mouse mastitis.
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http://dx.doi.org/10.1016/j.micpath.2020.104054DOI Listing
February 2020

Pore morphology and fractal dimension of ash deposited in catalyst diesel particulate filter.

Environ Sci Pollut Res Int 2020 Apr 17;27(10):11026-11037. Epub 2020 Jan 17.

National Laboratory of Auto Performance & Emission Test, School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China.

Diesel particle filter (DPF) has been widely acknowledged as the most effective way to mitigate particulate matter emitted from diesel engines. Over time, ash mainly derived from lubricating oil will deposit in DPF, showing negative influence to engine performance, fuel economy, service life of DPF, and so on. Recently, the investigation about DPF backpressure characteristics and DPF regeneration process considering ash has gained attention. As a porous material, ash will play a key role in the DPF permeability. Thus, the pore morphology and fractal dimension of ash derived from three kinds of lube are addressed in this work. The results show that the changing tendency of the micropore specific surface and pore volume is consistent with the ash content in lubricant oil, which is owing to the chemical interaction of Ca and S contained in the oil during the complex DPF regeneration. There is no significant changing tendency of the mesopore and macropore properties because of the heterogeneity and complexity of ash. According to the fractal analyses, the Avnir equation shows excellent predictive accuracy for the pore surface fractal dimension of ash, which reflects that the ash pore surfaces are irregular.
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http://dx.doi.org/10.1007/s11356-019-06945-7DOI Listing
April 2020

Observation and estimation of mercury exchange fluxes from soil under different crop cultivars and planting densities in North China Plain.

Environ Pollut 2020 Apr 17;259:113833. Epub 2019 Dec 17.

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No. 18 Shuangqing Road, Beijing 100085, China.

The emission of mercury (Hg) from cropland soil greatly affects the global Hg cycle. Combinations of different crop cultivars and planting densities will result in different light transmittance under canopies, which directly affects the solar and heat radiation flux received by the soil surface below crops. In turn, this might lead to differences in the soil-air total gaseous mercury (TGM) exchange under different cropping patterns. However, soil-air TGM exchange fluxes in croplands under differing canopies have been poorly investigated. Here, a one-year observation of TGM exchange flux was conducted for cropland soils covering five different crop cultivars and three planting densities in North China Plain using the dynamic flux chamber method. The results showed that light transmittance under the canopies was the key control on soil-air TGM exchange fluxes. High light transmittance can enhance soil TGM emission rates and increase the magnitude of diurnal variations in soil-air TGM exchange fluxes. Furthermore, we found that there were piecewise-function relationships (Peak function-constant equation) between light transmittance under the different canopies and the numbers of days after crop sowing. The soil-air TGM exchange fluxes showed a parabolic response to changes in light transmittance under the different canopies. A second-order model was established for the response relationship between soil-air TGM exchange flux and soil Hg concentration, total solar radiation above the canopy, and numbers of days after sowing. The estimated annual average soil-air TGM exchange flux was 5.46 ± 21.69 ng m h at corn-wheat rotation cropland with 30 cm row spacing using this second-order model. Our results might a data reference and a promising foundation for future model development of soil-air TGM exchange in croplands under different crop cultivars and planting densities.
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http://dx.doi.org/10.1016/j.envpol.2019.113833DOI Listing
April 2020

Regulated emission characteristics of in-use LNG and diesel semi-trailer towing vehicles under real driving conditions using PEMS.

J Environ Sci (China) 2020 Feb 5;88:155-164. Epub 2019 Aug 5.

National Laboratory of Auto Performance & Emission Test, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China.

On-road driving emissions of six liquefied natural gas (LNG) and diesel semi-trailer towing vehicles (STTVs) which met China Emission Standard IV and V were tested using Portable Emission Measurement System (PEMS) in northern China. Emission characteristics of these vehicles under real driving conditions were analyzed and proved that on-road emissions of heavy-duty vehicles (HDVs) were underestimated in the past. There were large differences among LNG and diesel vehicles, which also existed between China V vehicles and China IV vehicles. Emission factors showed the highest level under real driving conditions, which probably be caused by frequent acceleration, deceleration, and start-stop. NOx emission factors ranged from 2.855 to 20.939 g/km based on distance-traveled and 6.719-90.557 g/kg based on fuel consumption during whole tests, which were much higher than previous researches on chassis dynamometer. It was inferred from tests that the fuel consumption rate of the test vehicles had a strong correlation with NOx emission, and the exhaust temperature also affected the efficiency of Selected Catalytic Reduction (SCR) after-treatment system, thus changing the NOx emission greatly. THC emission factors of LNG vehicles were 2.012-10.636 g/km, which were much higher than that of diesel vehicles (0.029-0.185 g/km). Unburned CH may be an important reason for this phenomenon. Further on-road emission tests, especially CH emission test should be carried out in subsequent research. In addition, the Particulate Number (PN) emission factors of diesel vehicles were at a very high level during whole tests, and Diesel Particulate Filter (DPF) should be installed to reduce PN emission.
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http://dx.doi.org/10.1016/j.jes.2019.07.020DOI Listing
February 2020
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