Expansion Analysis of Yangtze River Delta Urban Agglomeration Using DMSP/OLS Nighttime Light Imagery for 1993 to 2012

Investigating the characteristics of urban expansion is helpful in managing the relationship between urbanization and the ecological and environmental issues related to sustainable development. The Defense Meteorological Satellite Program/Operational Line-scan System (DMSP/OLS) collects visible and near-infrared light from the Earth’s surface at night without moonlight. It generates effective time series data for mapping the dynamics of urban expansion. As a major urban agglomeration in the world, the Yangtze River Delta Urban Agglomeration (YRDUA) is an important intersection zone of both the “Belt and Road Initiative” and the “Yangtze River Economic Belt” in China. Therefore, this paper analyses urban expansion characteristics of the YRDUA for 1993–2012 from urban extents extracted from the DMSP/OLS for 1993, 1997, 2002, 2007, and 2012. First, calibration procedures are applied to DMSP/OLS data, including intercalibration, intra-annual composition, and inter-annual series correction procedures. Spatial extents are then extracted from the corrected DMSP/OLS data, and a threshold is determined via the spatial comparison method. Finally, three models are used to explore urban expansion characteristics of the YRDUA from expansion rates, expansion spatial patterns, and expansion evaluations. The results show that the urban expansion of the YRDUA occurred at an increasing rate from 1993–2007 and then declined after 2007 with the onset of the global financial crisis. The Suxichang and Ningbo metropolitan circles were seriously affected by the financial crisis, while the Hefei metropolitan circle was not. The urban expansion of the YRDUA moved from the northeast to the southwest over the 20-year period. Urban expansion involved internal infilling over the first 15 years and then evolved into external sprawl and suburbanization after 2007

Study on the Quality Control Chart for Determination of Soil Organic Carbon by Instrumental Analysis

【Objective】To ensure that each analysis step is in the monitoring state. The quality control chart is used to control the process of soil organic carbon content determination, and the reasons for drifting or exceeding the allowable value of the result data can be found out in time.【Method】The content of soil organic carbon in quality control samples was determined by instrumental analysis, and the quality control chart was drawn based on the determination data in Excel 2007, which was used for the quality control of the soil organic carbon content determination process.【Result】The control line of the mean control chart was 41.94% ~ 40.51%, and the warning limit was 41. 70% ~ 41. 74%. The control line range of the range control chart is 0.00% ~ 2.75%, and the warning limit is 0.00% ~ 2. 12%.【Conclusion】The quality control chart method is simple to operate,easy to master, and can timely find the abnormal points or abnormal trends of data, which has high application value in test analysis, and can ensure the accuracy of laboratory test results

The molecular phylogenetic position of Harpagocarpus (Polygonaceae) sheds new light on the infrageneric classification of Fagopyrum

In the context of the molecular phylogeny of Polygonaceae, the phylogenetic positions of most genera and their relationships have been resolved. However, the monotypic genus Harpagocarpus has never been included in any published molecular phylogenetic studies. In the present study, we adopt a two-step approach to confirm the phylogenetic placement of Harpagocarpus using two datasets: (1) a concatenated dataset of three chloroplast DNA (cpDNA) regions (matK, rbcL and trnL-F) for Polygonaceae and (2) a combined cpDNA dataset of five sequences (accD, matK, psbA-trnH, rbcL and trnL-F) for Fagopyrum. Our analyses confirm the previous hypothesis based on morphological, anatomical and palynological investigations that Harpagocarpus is congeneric with Fagopyrum and further reveal that H. snowdenii (≡ F. snowdenii) is sister to the woody buckwheat F. tibeticum. Within Fagopyrum, three highly supported clades were discovered and the first sectional classification was proposed to accommodate them: sect. Fagopyrum comprises the two domesticated common buckwheat (F. esculentum and F. tataricum) and their wild relatives (F. esculentum subsp. ancestrale, F. homotropicum and F. dibotrys) which are characterised by having large corymbose inflorescences and achenes greatly exceeding the perianth; sect. Tibeticum, including F. snowdenii and F. tibeticum, is characterised by the achene having appurtenances along the ribs, greatly exceeding the perianth and the perianth accrescent in fruit; sect. Urophyllum contains all other species of which the achenes were completely enclosed in the perianth. This study is very helpful to understand the phylogeny of the Fagopyrum and sheds light on the future study of taxonomy, biogeography, diversification and character evolution of the genus

PtrHAT22, as a higher hierarchy regulator, coordinately regulates secondary cell wall component biosynthesis in Populus trichocarpa

Homeodomain-leucine zipper (HD-Zip) II transcription factors (TFs) have been reported to play vital roles in diverse biological processes of plants. However, it remains unclear whether HD-Zip II TFs regulate secondary cell wall (SCW) in woody plants. In this study, we performed the functional characterization of a Populus trichocarpa HD-Zip II TF, PtrHAT22, which encodes a nuclear localized transcription repressor predominantly expressing in secondary developing tissues. Overexpression of PtrHAT22 showed arrested growths, including reduced heights and diameters above the ground, small leaves, and decreased biomass. Meanwhile, the contents of lignin, cellulose, and thickness of SCW significantly decreased, whilst the content of hemicellulose obviously increased in PtrHAT22 transgenic poplar. The expressions of some wood-associated TFs and structural genes significantly changed accordingly with the alternations of SCW characteristics in PtrHAT22 transgenic poplar. Furthermore, PtrHAT22 directly repressed the promoter activities of PtrMYB20, PtrMYB28, and PtrCOMT2, and bind two cis-acting elements that were specifically enriched in their promoter regions. Taken together, our results suggested that PtrHAT22, as a higher hierarchy TF like PtrWNDs, exerted coordination regulation of poplar SCW component biosynthesis through directly and indirectly regulating structural genes and different hierarchy TFs of SCW formation network

Electrochemistry Study of Permselectivity and Interfacial Electron Transfers of a Branch-Tailed Fluorosurfactant Self-Assembled Monolayer on Gold

We investigated the permselectivity and interfacial electron transfers of an amphiphilic branch-tailed fluorosurfactant self-assembled monolayer (FS-SAM) on a gold electrode by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The FS-SAM was prepared by a self-assembly technique and a “click„ reaction. The barrier property and interfacial electron transfers of the FS-SAM were also evaluated using various probes with different features. The FS-SAM allowed a higher degree of permeation by small hydrophilic (Cl− and F−) electrolyte ions than large hydrophobic (ClO4− and PF6−) ones. Meanwhile, the redox reaction of the Fe(CN)63− couple was nearly completely blocked by the FS-SAM, whereas the electron transfer of Ru(NH3)63+ was easier than that of Fe(CN)63−, which may be due to the underlying tunneling mechanism. For hydrophobic dopamine, the hydrophobic bonding between the FS-SAM exterior fluoroalkyl moieties and the hydrophobic probes, as well as the hydration resistance from the interior hydration shell around the oligo (ethylene glycol) moieties, hindered the transport of hydrophobic probes into the FS-SAM. These results may have profound implications for understanding the permselectivity and electron transfers of amphiphilic surfaces consisting of molecules containing aromatic groups and branch-tailed fluorosurfactants in their structures

Jasmonic Acid Signaling Pathway in Plants

Jasmonic acid (JA) and its precursors and dervatives, referred as jasmonates (JAs) are important molecules in the regulation of many physiological processes in plant growth and development, and especially the mediation of plant responses to biotic and abiotic stresses. JAs biosynthesis, perception, transport, signal transduction and action have been extensively investigated. In this review, we will discuss the initiation of JA signaling with a focus on environmental signal perception and transduction, JA biosynthesis and metabolism, transport of signaling molecules (local transmission, vascular bundle transmission, and airborne transportation), and biological function (JA signal receptors, regulated transcription factors, and biological processes involved)

Association of active Helicobacter pylori infection and anemia in elderly males

Abstract Background The prevalence of Helicobacter pylori (H. pylori) infection increases with age. However, the relationship between H. pylori infection and anemia in the elderly population remains to be identified. The aim of this study is to explore whether H. pylori infection is associated with anemia in a male elderly cohort. Methods A cross-sectional study was designed using data collected from asymptomatic male senior citizens (≥ 65 years old) who received an assessment of their health status at the General Hospital of Chinese PLA from January 2015 to December 2015. H. pylori infection was confirmed by the 13C-urea breath test. Blood samples from the participants were taken to assay for hemoglobin and other erythroid-related indices - serum iron, ferritin, and C-reactive protein (CRP). Anemia was defined as hemoglobin values lower than 120.0 g/L. Charlson Comorbidity Index (CCI) was applied to establish baseline comorbidities. Results Data from 646 subjects were analyzed. The mean age of the study cohort was 79.4 ± 8.9 years. The overall prevalence of H. pylori infection was 35.3%. The prevalence of anemia in the H. pylori positive group was higher than that in the negative group (5.3% vs. 2.2%, P = .033). Among the patients who had higher CCI scores (> 2), the prevalence of anemia in the H. pylori positive and negative groups were 10.3 and 1.4%, respectively (P = .009). Compared to the H. pylori negative group, the odds ratio for anemia of the H. pylori positive group was 2.53 (P = .033). No correlation between H. pylori infection and serum iron and ferritin levels was found. The mean corpuscular volume of the H. pylori positive and negative group was 91.17 ± 3.94 fl and 91.17 ± 4.09 fl (mean ± SD), respectively (P = .986). The CRP level in the H. pylori positive group was higher than that in the H. pylori negative group (Median: 0.17 mg/dL vs. 0.10 mg/dL, P < .001). Conclusion H. pylori infection seems to be associated with normocytic and normochromic anemia in elderly males, especially in those with more comorbidities. Further clinical studies are needed to verify the association

AIE-active photosensitizers for concomitant fluorescence visualization and efficient photodynamic elimination of multidrug-resistant bacteria

Multidrug resistance (MDR) bacterial infection is a serious hazard to human health. Photodynamic therapy (PDT) has been deployed as an emerging tactic to combat pathogenic bacteria, but the development of efficient photosensitizers against MDR bacteria still remains a global challenge. Herein, two near-infrared (NIR) photosensitizers, named TPA-Th and TPA-Ph, which feature aggregation-induced emission (AIE), were constructed and successfully employed for MDR bacteria monitoring and effective elimination. TPA-Th and TPA-Ph exhibited great affinity with MDR G(+) and G(−) bacteria via the electrostatic interaction between the cationic pyridinium segment and the negative bacterial envelope together with hydrophobic forces. Meanwhile, the reinforced D-A effect of the two cationic AIEgens further accelerated the intersystem crossing (ISC) process and enhanced the intramolecular charge transfer (ICT), resulting in the boosted ROS generation capability particularly in the case of predominant hydroxyl radicals. Therefore, superb photodynamic antibacterial performances were achieved for both MRSA and MDR E.coli with a low dose of the AIE photosensitizers. This study provides guidance for the development of high-performance AIE-active PSs with no antibiotic resistance to defeat MDR bacterial infections