Air PM samples from Beijing and six surrounding cities were collected during spring, summer, autumn, and winter. Levoglucosan (LG), mannosan (MN), and galactosan (GT) contents were analyzed by ion chromatography. The concentrations and distribution characteristics of the three anhydroglucoses with PM and organic carbon (OC) were compared. SPSS 24.0 was used to analyze the significant differences. The results indicated that the seasonal distributions of PM, OC, and LG in the six cities were highly similar and followed the order winter > spring > autumn > summer. There were significant differences in the concentration levels of the three anhydroglucoses in the four seasons. Between Beijing and Tianjin, Baoding, and Shijiazhuang, there was no significant difference in the three anhydroglucose concentrations. However, significant differences in the three anhydroglucose concentrations appeared between Beijing, Ji'nan, and Zhengzhou. Based on the ratios of LG/MN and LG/(MN+GT) measured in the six cities, it could be determined that the biomass combustion sources in PM mainly came from crop straw and hardwood in this region. During the air pollution process in spring, LG stably existed in PM in Beijing, Tianjin, Shijiazhuang, and Ji'nan, indicating that this pollution process was weakly affected by biomass combustion.
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http://dx.doi.org/10.13227/j.hjkx.201906029 | DOI Listing |
Front Oncol
December 2024
Department of Magnetic Resonance Imaging (MRI), The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology, Kunming, China.
Purpose: The aim of this study was to evaluate the diagnostic value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) derived kinetic parameters with high spatiotemporal resolution in discriminating malignant from normal prostate tissues.
Methods: Fifty patients with suspicious of malignant diseases in prostate were included in this study. Regions of interest (ROI) were manually delineated by experienced radiologists.
Introduction: Idiopathic Intracranial Hypertension (IIH) presents an increasing health burden with changing demographic patterns. We studied nationwide trends in IIH epidemiology, treatment patterns, and associated outcomes using a large-scale database analysis within the United States (US).
Methods: We performed a retrospective analysis using the TriNetX US Collaborative Network database (1990-2024).
Front Plant Sci
December 2024
LEAF-Linking Landscape, Environment, Agriculture and Food Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, Lisboa, Portugal.
Wheat is an essential staple food, and its production and grain quality are affected by extreme temperature events. These effects are even more relevant considering the increasing food demand for a growing world population and the predicted augmented frequency of heat waves. This study investigated the impact of simulated heat wave (HW) conditions imposed during grain filling on starch granule characteristics, endosperm ultrastructure, and transcriptomic modulation of genes involved in starch synthesis and degradation.
View Article and Find Full Text PDFWhile deep brain stimulation (DBS) remains an effective therapy for Parkinson's disease (PD), sources of variance in patient outcomes are still not fully understood, underscoring a need for better prognostic criteria. Here we leveraged routinely collected T1-weighted (T1-w) magnetic resonance imaging (MRI) data to derive patient-specific measures of brain structure and evaluate their usefulness in predicting changes in PD medications in response to DBS. Preoperative T1-w MRI data from 231 patients with PD were used to extract regional measures of fractal dimension (FD), sensitive to the structural complexities of cortical and subcortical areas.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Department of Laboratory Medicine and Pathobiology and Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
Introduction: Limited research has extensively analyzed neurodegenerative disease-related protein deposition patterns in the hippocampus.
Methods: This study examined the distribution of proteins in hippocampal subregions across major neurodegenerative diseases and explored their relation to each other. The area density of phosphorylated tau (p-tau), amyloid beta (Aβ), α-synuclein, and phosphorylated TDP-43 protein deposits together with pyramidal cell density in each hippocampal subregion, including CA1-4, prosubiculum (ProS), and subiculum was assessed in 166 cases encompassing various neurodegenerative diseases.
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