Publications by authors named "Xiaodong Li"

1,017 Publications

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Morphine Prevents Ischemia/Reperfusion-Induced Myocardial Mitochondrial Damage by Activating δ-opioid Receptor/EGFR/ROS Pathway.

Cardiovasc Drugs Ther 2021 Jul 19. Epub 2021 Jul 19.

School of Public Health, North China University of Science and Technology, 21 Bohai Avenue, Caofeidian District, Tangshan, 063000, Hebei, China.

Objective: The purpose of this study was to determine whether the epidermal growth factor receptor (EGFR), which is a classical receptor tyrosine kinase, is involved in the protective effect of morphine against ischemia/reperfusion (I/R)-induced myocardial mitochondrial damage.

Methods: Isolated rats hearts were subjected to global ischemia followed by reperfusion. Cardiac H9c2 cells were exposed to a simulated ischemia solution followed by Tyrode's solution to induce hypoxia/reoxygenation (H/R) injury. Triphenyltetrazolium chloride (TTC) was used to measure infarct size. The mitochondrial morphological and functional changes were determined using transmission election microscopy (TEM), mitochondrial stress assay, and mitochondrial swelling, respectively. Mitochondrial fluorescence indicator JC-1, DCFH-DA, and Mitosox Red were used to determine mitochondrial membrane potential (△Ψm), intracellular reactive oxygen species (ROS) and mitochondrial superoxide. A TUNUL assay kit was used to detect the level of apoptosis. Western blotting analysis was used to measure the expression of proteins.

Results: Treatment of isolated rat hearts with morphine prevented I/R-induced myocardial mitochondrial injury, which was inhibited by the selective EGFR inhibitor AG1478, suggesting that EGFR is involved in the mitochondrial protective effect of morphine under I/R conditions. In support of this hypothesis, the selective EGFR agonist epidermal growth factor (EGF) reduced mitochondrial morphological and functional damage similarly to morphine. Further study demonstrated that morphine may alleviate I/R-induced cardiac damage by inhibiting autophagy but not apoptosis. Morphine increased protein kinase B (Akt), extracellular regulated protein kinases (ERK) and signal transducer and activator of transcription-3 (STAT-3) phosphorylation, which was inhibited by AG1478, and EGF had similar effects, indicating that morphine may activate Akt, ERK, and STAT-3 via EGFR. Morphine and EGF increased intracellular reactive oxygen species (ROS) generation. This effect of morphine was inhibited by AG1478, indicating that morphine promotes intracellular ROS generation by activating EGFR. However, morphine did not increase ROS generation when cells were transfected with siRNA against EGFR. In addition, EGFR activity was markedly increased by morphine, but the effect of morphine was reversed by naltrindole. These results suggest that morphine may activate EGFR via δ-opioid receptor activation.

Conclusions: Morphine may prevent I/R-induced myocardial mitochondrial damage by activating EGFR through δ-opioid receptors, in turn increasing RISK and SAFE pathway activity via intracellular ROS. Moreover, morphine may reduce myocardial injury by regulating autophagy but not apoptosis.
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http://dx.doi.org/10.1007/s10557-021-07215-wDOI Listing
July 2021

Review of low-temperature plasma nitrogen fixation technology.

Waste Dispos Sustain Energy 2021 Jul 8:1-17. Epub 2021 Jul 8.

State Key Laboratory of Clean Energy Utilization, Department of Energy Engineering, Zhejiang University, Hangzhou, 310027 China.

Nitrogen fixation is essential for all forms of life, as nitrogen is required to biosynthesize fundamental building blocks of creatures, plants, and other life forms. As the main method of artificial nitrogen fixation, Haber-Bosch process (ammonia synthesis) has been supporting the agriculture and chemical industries since the 1910s. However, the disadvantages inherent to the Haber-Bosch process, such as high energy consumption and high emissions, cannot be ignored. Therefore, developing a green nitrogen fixation process has always been a research hotspot. Among the various technologies, plasma-assisted nitrogen fixation technology is very promising due to its small scale, mild reaction conditions, and flexible parameters. In the present work, the basic principles of plasma nitrogen fixation technology and its associated research progress are reviewed. The production efficiency of various plasmas is summarized and compared. Eventually, the prospect of nitrogen fixation using low-temperature plasma in the future was proposed.
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http://dx.doi.org/10.1007/s42768-021-00074-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8264177PMC
July 2021

Pressure-Induced Electronic and Structural Transition in Nodal-Line Semimetal ZrSiSe.

Inorg Chem 2021 Jul 9. Epub 2021 Jul 9.

State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China.

The nodal-line semimetals have recently gained attention as a promising material due to their exotic electronic structure and properties. Here, we investigated the structural evolution and physical properties of nodal-line semimetal ZrSiSe under pressure via experiments and theoretical calculations. An isostructural electronic transition is observed at ∼6 GPa. Upon further compression, the original tetragonal phase starts to transform into an orthorhombic phase at ∼13 GPa and the two phases coexist until the maximal experimental pressure. By analysis of the electronic band structure, we suggest that the significant changes in the Fermi surface contribute to the occurrence of the isostructural electronic transition. The results provide a new insight into the structure and properties of ZrSiSe.
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http://dx.doi.org/10.1021/acs.inorgchem.1c01087DOI Listing
July 2021

Acidic Microenvironment Aggravates the Severity of Hepatic Ischemia/Reperfusion Injury by Modulating M1-Polarization Through Regulating PPAR-γ Signal.

Front Immunol 2021 21;12:697362. Epub 2021 Jun 21.

Hepatopancreatobiliary Surgery Department, The Third Affiliated Hospital of Soochow University, Changzhou First People's Hospital, Changzhou, China.

Hepatic injury induced by ischemia and reperfusion (HIRI) is a major clinical problem after liver resection or transplantation. The polarization of macrophages plays an important role in regulating the severity of hepatic ischemia/reperfusion injury. Recent evidence had indicated that the ischemia induces an acidic microenvironment by causing increased anaerobic glycolysis and accumulation of lactic acid. We hypothesize that the acidic microenvironment might cause the imbalance of intrahepatic immunity which aggravated HIRI. The hepatic ischemia/reperfusion injury model was established to investigate the effect of the acidic microenvironment to liver injury. Liposomes were used to deplete macrophages . Macrophages were cultured under low pH conditions to analyze the polarization of macrophages . Activation of the PPAR-γ signal was determined by Western blot. PPAR-γ agonist GW1929 was administrated to functionally test the role of PPAR-γ in regulating macrophage-mediated effects in the acidic microenvironment during HIRI. We demonstrate that acidic microenvironment aggravated HIRI while NaHCO reduced liver injury through neutralizing the acid, besides, liposome abolished the protective ability of NaHCO through depleting the macrophages. In vivo and vitro experiment showed that acidic microenvironment markedly promoted M1 polarization but inhibited M2 polarization of macrophage. Furthermore, the mechanistic study proved that the PPAR-γ signal was suppressed during the polarization of macrophages under pH = 6.5 culture media. The addition of PPAR-γ agonist GW1929 inhibited M1 polarization under acidic environment and reduced HIRI. Our results indicate that acidic microenvironment is a key regulator in HIRI which promoted M1 polarization of macrophages through regulating PPAR-γ. Conversely, PPAR-γ activation reduced liver injury, which provides a novel therapeutic concept to prevent HIRI.
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http://dx.doi.org/10.3389/fimmu.2021.697362DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8255974PMC
June 2021

Impact of Dietary Protein Content on Soil Bacterial and Fungal Communities in a Rice-Crab Co-culture System.

Front Microbiol 2021 21;12:696427. Epub 2021 Jun 21.

Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, China.

Although co-culture of paddy fields with aquatic animals is lucrative, the ecological impacts of high-protein content entering the agricultural soil via animal pellet feed and feces have not been well studied. Moreover, the effects of dietary protein on soils and soil microbes remain unclear. To elucidate this, we examined soil bacterial and fungal community composition and temporal changes in paddy fields subjected to different protein-content diets via 16S/18S rRNA gene amplicon sequencing analysis with a high-throughput next-generation sequencer. MiSeq sequencing revealed that protein content significantly impacted fungal community structure. High-protein diets reduced bacterial community diversity and relative abundance in both July and October. The phylum-level bacterial taxonomic composition was not affected by diet treatment, while in fungi, a major phylum-level shift was evident. Hierarchically clustered analysis showed that high-protein diets significantly reduced the relative abundance of in both July and October. Saprotrophic macrofungal diversity was negatively related to dietary protein content. Considering microbial community structure and environmental factors, ca. 15% protein content is appropriate for the rice-crab co-culture system that we studied.
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http://dx.doi.org/10.3389/fmicb.2021.696427DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8256891PMC
June 2021

Post-modified Strategies of Graphdiyne for Electrochemical Applications.

Chem Asian J 2021 Jul 1. Epub 2021 Jul 1.

Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, P. R. China.

The new carbon material graphdiyne (GDY) has been verified to have a great application prospect in electrochemical field. In order to study its properties and expand its scope of application, various experiments including structural control tests are imposed on GDY. Among them, as one of the most commonly used methods to modify the structure, heteroatom doping is favored for its advantages in synthesis methods and the control of mechanical, electrical and even magnetic properties of carbon materials. According to the published studies, the top-down methods of doping heteroatoms for GDY only need cheap raw materials, simple synthetic route and strong controllability, which is conducive to rapid performance breakthroughs in electrochemical applications. This review selects the typical cases in the development of that post-modification method from the application of GDY in the electrochemical field. Here, based on the existed reports, the commonly used non-metal elements (such as nitrogen, sulfur) and metal elements (such as iron) have been introduced to post-modify GDY. Then, a detailed analysis is made for corresponding electrochemical applications, such as energy storage and electrocatalysis. Finally, the challenges and prospects of post-modified GDY in synthesis and electrochemical applications are proposed. This review provides us a useful guidance for the development of high-quality GDY suitable for electrochemical applications.
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http://dx.doi.org/10.1002/asia.202100579DOI Listing
July 2021

Effects of Bedtime Dosing With Suvorexant and Zolpidem on Balance and Psychomotor Performance in Healthy Elderly Participants During the Night and in the Morning.

J Clin Psychopharmacol 2021 Jul-Aug 01;41(4):414-420

Merck & Co Inc, Kenilworth, NJ.

Purpose/background: This study was designed as an early assessment of the safety of the orexin receptor antagonist suvorexant, but also included exploratory assessments of balance and psychomotor performance that are the focus of this report.

Methods/procedures: This was a double-blind, randomized, 3-period, crossover, phase 1 study. Balance and psychomotor performance were evaluated during the night in 12 healthy elderly participants after bedtime administration of suvorexant 30 mg (a supratherapeutic dose), the GABAergic agonist zolpidem 5 mg (the recommended dose in the elderly), or placebo. Balance (body sway measured by platform stability) and psychomotor performance (measured by choice reaction time) were assessed predose and at 1.5, 4, and 8 hours postdose in each period. Memory (measured by word recall) was assessed predose and at 4 hours postdose.

Findings/results: At 1.5 hours after nighttime administration of each drug (the approximate time of their anticipated maximal plasma concentrations), both zolpidem and suvorexant increased body sway versus placebo, with a greater increase for zolpidem than suvorexant. Suvorexant increased choice reaction time compared with placebo or zolpidem at 1.5 hours. There were no treatment differences on body sway or choice reaction time at 4 or 8 hours, or on word recall at 4 hours.

Implications/conclusions: These exploratory data suggest that a 30-mg dose of suvorexant (supratherapeutic) and a 5-mg dose of zolpidem (recommended dose in the elderly) impaired balance at 1.5 hours in healthy elderly people, with potentially less impairment for suvorexant relative to zolpidem, but no treatment differences on body sway or psychomotor performance at 4 and 8 hours. Because of their exploratory nature, these findings and their clinical relevance, if any, require confirmation in a prospective study.
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http://dx.doi.org/10.1097/JCP.0000000000001439DOI Listing
June 2021

Drug Repurposing for the Treatment of COVID-19: A Knowledge Graph Approach.

Adv Ther (Weinh) 2021 May 20:2100055. Epub 2021 May 20.

Centre for Safe Medication Practice and Research Department of Pharmacology and Pharmacy LKS Faculty of Medicine University of Hong Kong Hong Kong Special Administrative Region, 1/F, Jockey Club Building for Interdisciplinary Research, 5 Sassoon Road Pokfulam Hong Kong SAR China.

Identifying effective drug treatments for COVID-19 is essential to reduce morbidity and mortality. Although a number of existing drugs have been proposed as potential COVID-19 treatments, effective data platforms and algorithms to prioritize drug candidates for evaluation and application of knowledge graph for drug repurposing have not been adequately explored. A COVID-19 knowledge graph by integrating 14 public bioinformatic databases containing information on drugs, genes, proteins, viruses, diseases, symptoms and their linkages is developed. An algorithm is developed to extract hidden linkages connecting drugs and COVID-19 from the knowledge graph, to generate and rank proposed drug candidates for repurposing as treatments for COVID-19 by integrating three scores for each drug: motif scores, knowledge graph PageRank scores, and knowledge graph embedding scores. The knowledge graph contains over 48 000 nodes and 13 37 000 edges, including 13 563 molecules in the DrugBank database. From the 5624 molecules identified by the motif-discovery algorithms, ranking results show that 112 drug molecules had the top 2% scores, of which 50 existing drugs with other indications approved by health administrations reported. The proposed drug candidates serve to generate hypotheses for future evaluation in clinical trials and observational studies.
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http://dx.doi.org/10.1002/adtp.202100055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8212091PMC
May 2021

Cooperatively assembled liquid crystals enable temperature-controlled Förster resonance energy transfer.

Chem Sci 2021 Jan 26;12(9):3146-3151. Epub 2021 Jan 26.

Department of Chemistry, Washington State University Pullman WA 99164 USA

Balancing the rigidity of a π-conjugated structure for strong emission and the flexibility of liquid crystals for self-assembly is the key to realizing highly emissive liquid crystals (HELCs). Here we show that (1) integrating organization-induced emission into dual molecular cooperatively-assembled liquid crystals, (2) amplifying mesogens, and (3) elongating the spacer linking the emitter and the mesogen create advanced materials with desired thermal-optical properties. Impressively, assembling the fluorescent acceptor Nile red into its host donor designed according to the aforementioned strategies results in a temperature-controlled Förster resonance energy transfer (FRET) system. Indeed, FRET exhibits strong S-curve dependence as temperature sweeps through the liquid crystal phase transformation. Such thermochromic materials, suitable for dynamic thermo-optical sensing and modulation, are anticipated to unlock new and smart approaches for controlling and directing light in stimuli-responsive devices.
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http://dx.doi.org/10.1039/d0sc06838aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8179397PMC
January 2021

Evolution of fusion and PCDD/F-signatures of boiler ash from a mechanical grate municipal solid waste incinerator.

Chemosphere 2021 Oct 20;280:130922. Epub 2021 May 20.

State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China; National Engineering Laboratory for Waste Incineration Technology and Equipment, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.

Boiler ash formed at different temperature ranges in a typical mechanical grate incinerator is collected and systemically studied, with the aim of providing a reference for ash disposal and revealing the formation routes and distribution of polychlorinated ρ-dibenzodioxins and dibenzofurans (PCDD/Fs). Key physical and chemical properties are carefully analyzed, including chemical component, ash fusion temperatures (AFTs), crystalline phases, chemical species, and PCDD/Fs. Several fouling and slagging indices are introduced and their relationships with AFT are revealed. The fouling index (F) and a slagging index (R) are well fitted with ash flow temperatures, with correlation coefficient (R) of 0.82 and 0.82, respectively; these could be better potential indices for disposal applications of municipal solid waste incineration fly ash. CC/C-C/C-H (69.25-80.93%) and inorganic chlorine (94.23-98.68%) are the dominant carbon and chlorine species, respectively. The increasing AFT is mainly attributed to the changing components, the increasing proportions of crystalline CaSO, NaCl and KCl and the decreasing crystallinity and content of SiO. Twice as much PCDD/Fs is generated by the low-temperature heterogeneous reaction (6.71-19.22 ng/g) than by the high-temperature homogeneous reaction (0.59-6.71 ng/g). The proportions of highly chlorinated homologues increase and gradually become the main component. Principal component analysis reveals that PCDD/Fs is positively correlated with Cl, Cu, Pb, Sn, Sb, Zn and CC/C-C/C-H but negatively correlated with less volatile elements, e.g., Ni, Mn, Al, Ti, Si, and Cr. These results can benefit further research on boiler ash disposal and PCDD/F formation routes in the post-combustion area of incinerators.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130922DOI Listing
October 2021

Investigation of an MAA Test With Virtual Sound Synthesis.

Front Psychol 2021 2;12:656052. Epub 2021 Jun 2.

School of Electronics and Communication Engineering, Guangzhou University, Guangzhou, China.

The ability to localize a sound source is very important in our daily life, specifically to analyze auditory scenes in complex acoustic environments. The concept of minimum audible angle (MAA), which is defined as the smallest detectable difference between the incident directions of two sound sources, has been widely used in the research fields of auditory perception to measure localization ability. Measuring MAAs usually involves a reference sound source and either a large number of loudspeakers or a movable sound source in order to reproduce sound sources at a large number of predefined incident directions. However, existing MAA test systems are often cumbersome because they require a large number of loudspeakers or a mechanical rail slide and thus are expensive and inconvenient to use. This study investigates a novel MAA test method using virtual sound source synthesis and avoiding the problems with traditional methods. We compare the perceptual localization acuity of sound sources in two experimental designs: using the virtual presentation and real sound sources. The virtual sound source is reproduced through a pair of loudspeakers weighted by vector-based amplitude panning (VBAP). Results show that the average measured MAA at 0° azimuth is 1.1° and the average measured MAA at 90° azimuth is 3.1° in a virtual acoustic system, meanwhile the average measured MAA at 0° azimuth is about 1.2° and the average measured MAA at 90° azimuth is 3.3° when using the real sound sources. The measurements of the two methods have no significant difference. We conclude that the proposed MAA test system is a suitable alternative to more complicated and expensive setups.
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http://dx.doi.org/10.3389/fpsyg.2021.656052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8206507PMC
June 2021

Effective Surface Treatment for High-Performance Inverted CsPbIBr Perovskite Solar Cells with Efficiency of 15.92.

Nanomicro Lett 2020 Aug 19;12(1):170. Epub 2020 Aug 19.

Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, People's Republic of China.

Highlights: A simple and multifunctional surface treatment strategy is proposed to address the inferior-performance inverted CsPbIBr perovskite solar cells (PSCs). The induced-ions exchange can align energy levels, passivate both GBs and surface, and gift the solid protection from external erosions. The inverted CsPbIBr PSCs reveal a champion efficiency of 15.92% and superior stability after moisture, operational, and thermal ages. Developing high-efficiency and stable inverted CsPbIBr perovskite solar cells is vitally urgent for their unique advantages of removing adverse dopants and compatible process with tandem cells in comparison with the regular. However, relatively low opening circuit voltage (V) and limited moisture stability have lagged their progress far from the regular. Here, we propose an effective surface treatment strategy with high-temperature FABr treatment to address these issues. The induced ions exchange can not only adjust energy level, but also gift effective passivation. Meanwhile, the gradient distribution of FA can accelerate the carriers transport to further suppress bulk recombination. Besides, the Br-rich surface and FA substitution can isolate moisture erosions. As a result, the optimized devices show champion efficiency of 15.92% with V of 1.223 V. In addition, the tolerance of humidity and operation get significant promotion: maintaining 91.7% efficiency after aged at RH 20% ambient condition for 1300 h and 81.8% via maximum power point tracking at 45 °C for 500 h in N. Furthermore, the unpackaged devices realize the rare reported air operational stability and, respectively, remain almost efficiency (98.9%) after operated under RH 35% for 600 min and 91.2% under RH 50% for 300 min.
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http://dx.doi.org/10.1007/s40820-020-00509-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770732PMC
August 2020

Effect of captopril pretreatment on the dentin bonding durability of self-etch adhesive.

Zhejiang Da Xue Xue Bao Yi Xue Ban 2021 04;50(2):179-186

Stomatology Hospital.

To investigate the effect of captopril on the dentin bonding durability of self-etch adhesive. Different concentrations of captopril ethanol solutions or captopril ethanol/water solutions were prepared to pretreat dentin as primer for the self-etch adhesives. The surface morphology of the dentin was observed with scanning electron microscopy (SEM). Based on the morphology analysis, the pretreatment condition was selected and two self-etch adhesives were employed to evaluate the improvement effect of the captopril pretreatment on the dentin bonding durability. : SEM showed that the pretreatment of captopril ethanol solutions and captopril ethanol/water solutions were able to remove the smear lay and partially expose collagen matrix. According to the SEM results, the pretreating condition of captopril ethanol/water solution with the pretreating time of was selected for further dentin bonding study. For Clearfil SEBOND system, the immediate bonding strength increased from to  (<0.05). After one-year aging, the bonding strength of the control group decreased markedly [(22.90±6.82) MPa, <0.05]; while the bonding strength of the captopril pretreated group kept steadily >0.05]. For Clearfil S BOND system, there was no significant difference in the immediate bonding strength between the experimental group [(4.07) MPa] and the control group[(4.11) MPa]. But after one-year aging, the bonding strength of the experimental group was higher than that of the control group <0.05]. : The pretreatment with captopril ethanol/water solution increases the dentin bonding strength of the self-etch adhesive systems and also improves the bonding durability.
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http://dx.doi.org/10.3724/zdxbyxb-2021-0116DOI Listing
April 2021

Clinical application for DSA combined with a double-chamber Fogarty catheter in the treatment of venous crisis.

Wideochir Inne Tech Maloinwazyjne 2021 Jun 25;16(2):347-354. Epub 2020 Nov 25.

Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical College, Chengde City, China.

Introduction: Venous crisis, as a common vascular crisis post limb replantation, is usually treated with surgical exploration.

Aim: To investigate effects of digital subtraction angiography (DSA) combined with double-chamber Fogarty balloon catheter on venous crisis post replantation of limbs.

Material And Methods: Twelve patients suffering from severed limbs were involved in this study. Patients underwent DSA combining double-chamber Fogarty balloon catheter operation. Colour Doppler ultrasound was used to diagnose patients with venous crisis. Patients were treated with rehydration, anti-infection, anticoagulation, and vasodilation. Indexes, including total joint active activity, working condition, remaining symptoms, appearance, feeling, and muscle strength, were evaluated.

Results: During operation, the limb was shortened to 0-1 cm in 8 cases, to 1-2 cm in 2 cases, and to 2-2.5 cm in 2 cases. According to DSA findings, popliteal vein thrombosis was formed at 0.6-4.2 cm and was removed from the popliteal vein. After removal of the thrombosis, DSA images showed re-canalization of the popliteal vein. A typical case of a 16-year-old patient underwent limb replantation; however, venous crisis was formed post operation. Postoperative colour Doppler ultrasound findings indicated re-canalization of the popliteal vein. Tibia and fibula were reduced and internally fixed, while the limb was survived post-operation. The degree of swelling of limbs was improved, and skin temperature was normal or 0.6-1.5°C lower than affected limbs. Skin colour was normal and activity was improved. Patients demonstrated sensory recovery grade of S and two-point discrimination of 4.5 mm.

Conclusions: DSA combining double-chamber Fogarty balloon catheter, as a minimally invasive and fast approach, could accurately locate thrombi and improve pertinence of vein branches.
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http://dx.doi.org/10.5114/wiitm.2020.101231DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8193746PMC
June 2021

New Mg/Ge-Stabilized GdMgGeAlO:Ce Garnet Phosphor with Orange-Yellow Emission for Warm-White LEDs ( = 2.0-2.5).

Inorg Chem 2021 Jul 17;60(13):9773-9784. Epub 2021 Jun 17.

Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.

By stabilization of the GdAlO garnet by replacing 80% or more of Al with Mg/Ge pairs, a series of new orange-yellow-emitting GdMgGeAlO:Ce ( = 2.0-2.5) phosphors were successfully developed for potential application in warm-white-light-emitting diodes (WLEDs). Rietveld structure refinement proved that Mg first substitutes the octahedral Al ion, followed by the replacement of the tetrahedral Al together with Ge. The band structure of the = 2.0 typical garnet was analyzed via density functional theory (DFT) calculations. The incorporation of an increasing content of Mg/Ge was experimentally shown to narrow the band gap and expand the unit cell of the garnet host and blue shift the emission/excitation wavelength and shorten the fluorescence lifetime of Ce. The photoluminescence behaviors were rationalized by considering the influence of Mg/Ge on the crystal structure, band structure, and local coordination. An LED lamp fabricated by combining the (GdCe)MgGeAlO optimal phosphor with a 450 nm-emitting InGaN blue LED chip exhibited a color-rendering index of 71.6, luminous efficacy of 16.1 lm/W, and a low correlated color temperature of 2201 K under a driving current of 20 mA, indicating that phosphor may have potential application in warm WLEDs.
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http://dx.doi.org/10.1021/acs.inorgchem.1c01072DOI Listing
July 2021

Simulated In Vitro Infant Gastrointestinal Digestion of Infant Formulas Containing Different Fat Sources and Human Milk: Differences in Lipid Profiling and Free Fatty Acid Release.

J Agric Food Chem 2021 Jun 14;69(24):6799-6809. Epub 2021 Jun 14.

Food College, Northeast Agricultural University, No. 600 Changjiang St., Xiangfang Dist, 150030 Harbin, China.

Simulated in vitro infant gastrointestinal digestion of human milk and four infant formulas containing different fat sources was analyzed and compared in this study. Although there are disadvantages brought about by its larger droplet size than infant formulas, human milk exhibited a higher lipolysis level due to the presence of MFGM interfacial layers. Higher hydrolysis efficiency of infant formulas (IFB, IFC, and IFM) was due to the presence of MFGM/phospholipid-enriched materials. Human milk released higher free fatty acid levels, especially long-chain fatty acid, and less undigested TAG molecules at the end of digestion than infant formulas. Human milk had a higher proportion of MAG and DAG linked to long-chain fatty acid. Furthermore, several lipids were identified as potential biomarkers that could be used to further analyze differences in the biological properties of human, bovine, and caprine milk. This comprehensive analysis might be fruitful to formulate an infant formula closest to human milk.
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http://dx.doi.org/10.1021/acs.jafc.1c01760DOI Listing
June 2021

Exploring the role of Fe species from biochar-iron composites in the removal and long-term immobilization of SeO against competing oxyanions.

J Hazard Mater 2021 Jun 6;418:126311. Epub 2021 Jun 6.

College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.

Carbothermal reduction is a convenient and cost-effective method to produce biochar (BC) supported iron-based nano-particles (INP) for oxyanion contaminants removal. However, considering the possible desorption of the target oxyanion during change of the surrounding environment, the detailed removal mechanisms remain unclear and the long-term efficiency of different INPs cannot be predicted. In this study, different BC/Fe composites were synthesized by controlling the pyrolysis temperatures (500-800 °C). BC/FeO composite synthesized at 500 °C (BC/Fe) possessed the strongest surface acidity thus with the best SeO removal performance, and BC/Fe/FeO composite synthesized at 650 °C (BC/Fe) possessed the best reducing ability toward SeO. Through the co-removal experiments (SeO and common competing oxyanions co-existed) and the investigation of Se stability loaded on BC/Fe composites, the removal of SeO by BC/Fe through highly reversible adsorption could not achieve long-term immobilization of Se, making it an appropriate adsorbent for pre-treatment only, while the efficient reduction of SeO to Se by BC/Fe could largely improve its long-term stability. This study supplies a possible strategy for Se immobilization against common competing oxyanions.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126311DOI Listing
June 2021

Dynamics of the SARS-CoV-2 antibody response up to 10 months after infection.

Cell Mol Immunol 2021 07 7;18(7):1832-1834. Epub 2021 Jun 7.

Ministry of Education and State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

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http://dx.doi.org/10.1038/s41423-021-00708-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8182358PMC
July 2021

CircMAPK1 promotes the proliferation and migration of vascular smooth muscle cells through miR-22-3p/ methyl-CpG binding protein 2 axis.

Nutr Metab Cardiovasc Dis 2021 Jun 20;31(7):2189-2198. Epub 2021 Apr 20.

Department of Cardiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, 110004, PR China. Electronic address:

Background And Aims: Atherosclerosis is a chronic inflammatory disease. The proliferation and migration of vascular smooth muscle cells (VSMCs) contribute to intimal hyperplasia. CircRNAs are class of endogenous RNA and implicated in the various biological processes. However, the role of circRNAs in atherosclerosis remains largely unknown.

Methods And Results: Mice models of atherosclerosis were established using APOE mice fed with high-fat diet. High-throughput sequencing was performed to profile the expression of circRNAs in atherosclerosis. A total of 1289 circRNAs were identified. Six circRNAs were up-regulated and 12 circRNAs were down-regulated in the atherosclerotic plaque tissues. Then we focused on circMAPK1, which showed a high level in atherosclerosis. Silencing circMAPK1 suppressed the proliferation and migration of VSMCs. Further study showed that circMAPK1 bound with miR-22-3p. CircMAPK1 silencing increased the level of miR-22-3p and suppressed the level of MECP2, a known target of miR-22-3p. Interestingly, suppression of miR-22-3p rescued the effect of circMAPK1 silencing on the proliferation and migration of VSMCs.

Conclusion: CircMPAK1 promoted the proliferation and migration of VSMCs through miR-22-3p/MECP2 axis. Our study revealed the role of circMAPK1 in atherosclerosis and shed lights on the treatment of atherosclerosis.
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http://dx.doi.org/10.1016/j.numecd.2021.04.005DOI Listing
June 2021

A limited panel of INSM1 and LEF1 immunostains accurately distinguishes between pancreatic neuroendocrine tumor and solid pseudopapillary neoplasm.

Pathol Res Pract 2021 Jul 13;223:153462. Epub 2021 May 13.

Department of Pathology and Laboratory Medicine, University of California, Irvine, CA, United States. Electronic address:

Solid pseudopapillary neoplasm (SPN) and well differentiated pancreatic neuroendocrine tumor (PNET) can show significant cytomorphological overlap. In this study, we evaluated the role of INSM1 and LEF1 immunohistochemical stains in distinguishing between these two tumors. 22 SPN and 25 PNET surgically resected cases were stained for both INSM1 and LEF1. All the 22 cases of SPN showed strong and diffuse nuclear staining for LEF1 (in >95 % of tumor cells), while all 25 PNET were negative for LEF1. All 25 PNET cases were positive for INSM1 (moderate to strong intensity nuclear staining in >50 % of the tumor cells), while all 22 cases of SPN were negative for INSM1. The results of our study show that a limited panel comprising of INSM1 and LEF1 immunostains accurately distinguishes between SPN and PNET.
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http://dx.doi.org/10.1016/j.prp.2021.153462DOI Listing
July 2021

Complete remission of choriocarcinoma with pulmonary vein thrombosis in the third trimester of pregnancy treated with systemic chemotherapy and anticoagulation: A case report.

Medicine (Baltimore) 2021 May;100(21):e26145

Department of Obstetrics and Gynecology, The Second Hospital of Hebei Medical University, Shijiazhuang, China.

Rationale: Choriocarcinoma is a highly aggressive tumor. It occurs infrequently during pregnancy. The management of choriocarcinoma during pregnancy poses several challenges.

Patient Concerns: At 34 weeks of gestation, a 21-year-old primigravida was transferred to the emergency room for cephalgia, reduced fetal movements, and left intra-atrial intracavitary thrombus.

Diagnosis: Choriocarcinoma in the third trimester with lung and brain metastases, pulmonary vein thrombosis (PVT), and systemic thrombosis.

Intervention: An emergency cesarean section was performed. Subsequently, low-molecular-weight heparin anticoagulation combined with multiagent chemotherapy was administered.

Outcome: A 1.59 kg live female was born. Multiagent chemotherapy combined with anticoagulation led to complete regression of the cerebral and pulmonary lesions and the dissolution of pulmonary vein thrombus. At the 11-month follow-up, the patient remained in complete remission without complications, and her child was disease-free.

Lessons: This is the first case of gestational choriocarcinoma with PVT. Our case suggests that conservative therapy can be the first choice for small, asymptomatic PVT secondary to choriocarcinoma.
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http://dx.doi.org/10.1097/MD.0000000000026145DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154502PMC
May 2021

Detecting changes in water level caused by climate, land cover and dam construction in interconnected river-lake systems.

Sci Total Environ 2021 Sep 15;788:147692. Epub 2021 May 15.

College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.

There is a growing recognition of the broader environmental significance of exploring the relative importance of climate change and anthropogenic impacts on hydrologic fluctuations in river-lake systems. In the case of Dongting Lake, the typical river-lake system, we collected the water level from 1990 to 2019, spanning before and after the operation of the Three Gorges Dam (TGD) in 2003. This study was conducted to detect water level fluctuations in Dongting Lake and to quantify the relative influence of climate, land cover and dam construction on water levels. We defined the impact of the dam construction as the three inlets inflow of Yangtze River (In-YR), and four waters inflow of Hunan (In-HN). The Mann-Kendall (M-K) test revealed the trends and change points of water level fluctuations. Structural Equation Model (SEM) was used to detect the direct and indirect effects of these factors on water level and quantify their relative importance. The MIKE21 hydrodynamic model reflected the spatial-temporal variability of water levels under the action of key driver. The results showed that the water level appeared a downward trend during 1990-2019 and the change point appeared in 2003; During 1990-2002, the significant factors were: precipitation (V = 0.469, P = 0.013), evaporation (V = -0.424, P = 0.029), non-agricultural cover (V = -0.334, P = 0.025), and agricultural cover (V = 0.235, P = 0.033); During 2003-2019, the significant factors were: In-YR (V = 0.436, P = 0.007), In-HN (V = 0.431, P = 0.012), and precipitation (V = 0.349, P = 0.045); The In-YR was the key factor affecting the changes of the water level during 1990-2019; Under the influence of In-YR, the most obvious fluctuation of water level was in the flood adjustment period (Jun-Aug) and the impoundment period (Sep-Nov) when the average declined by about 0.50 and 0.67 m, respectively. Our findings provide a new insight into how to better maintain the stability of river-water system water resources under the influence of multiple factors.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147692DOI Listing
September 2021

Hepatic Artery Infusion of Floxuridine in Combination With Systemic Chemotherapy for Pancreatic Cancer Liver Metastasis: A Propensity Score-Matched Analysis in Two Centers.

Front Oncol 2021 28;11:652426. Epub 2021 Apr 28.

Interventional Radiology Center, Department of Radiology, Xiangya Hospital Central South University, Changsha, China.

Aim: To evaluate the efficacy of hepatic artery infusion (HAI) of floxuridine (FUDR) in combination with systemic chemotherapy in patients with pancreatic cancer liver metastases (PCLM).

Patients And Methods: We retrospectively collected clinical data of 347 patients with PCLM who underwent first-line chemotherapy at two Chinese centers between 2012 and 2019. Propensity score matching between patients with and without HAI was performed to compensate for differences in baseline characteristics. Objective response rate (ORR) and overall survival (OS) between groups were compared. HAI pump functionality was recorded.

Results: Data of 258 patients (62 patients with HAI and 196 patients without HAI) were used for matching. After 1:1 ratio matching, 62 patients per group were included. The intrahepatic ORR was 66.1% in the HAI group and 22.6% in the non-HAI group ( < 0.001), and the extrahepatic ORR was 25.0 28.9% ( = 0.679). The median OS was significantly longer in HAI group (14.0 10.8 months, = 0.001). Multivariance COX regression showed HAI led to a decrease in hazard ratio for death by 61.8% (HR = 0.382; 95% CI: 0.252-0.578; < 0.001). Subgroup analysis revealed that patients without EHM, with higher intrahepatic tumor burden and with synchronous liver metastasis benefited more from HAI. Dysfunction of HAI pump occurred in 5.7% of patients during the period of follow-up.

Conclusions: In patients with PCLM, first-line treatment with HAI FUDR plus SCT resulted in higher intrahepatic response and better OS.
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http://dx.doi.org/10.3389/fonc.2021.652426DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113695PMC
April 2021

The Epigenetic Modulation of Cancer and Immune Pathways in Hepatitis B Virus-Associated Hepatocellular Carcinoma: The Influence of HBx and miRNA Dysregulation.

Front Immunol 2021 29;12:661204. Epub 2021 Apr 29.

Hepatitis Virus Diversity Research Unit, School of Internal Medicine, University of the Witwatersrand, Johannesburg, South Africa.

Hepatitis B virus (HBV)-associated hepatocellular carcinoma (HBV-HCC) pathogenesis is fueled by persistent HBV infection that stealthily maintains a delicate balance between viral replication and evasion of the host immune system. HBV is remarkably adept at using a combination of both its own, as well as host machinery to ensure its own replication and survival. A key tool in its arsenal, is the HBx protein which can manipulate the epigenetic landscape to decrease its own viral load and enhance persistence, as well as manage host genome epigenetic responses to the presence of viral infection. The HBx protein can initiate epigenetic modifications to dysregulate miRNA expression which, in turn, can regulate downstream epigenetic changes in HBV-HCC pathogenesis. We attempt to link the HBx and miRNA induced epigenetic modulations that influence both the HBV and host genome expression in HBV-HCC pathogenesis. In particular, the review investigates the interplay between CHB infection, the silencing role of miRNA, epigenetic change, immune system expression and HBV-HCC pathogenesis. The review demonstrates exactly how HBx-dysregulated miRNA in HBV-HCC pathogenesis influence and are influenced by epigenetic changes to modulate both viral and host genome expression. In particular, the review identifies a specific subset of HBx induced epigenetic miRNA pathways in HBV-HCC pathogenesis demonstrating the complex interplay between HBV infection, epigenetic change, disease and immune response. The wide-ranging influence of epigenetic change and miRNA modulation offers considerable potential as a therapeutic option in HBV-HCC.
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http://dx.doi.org/10.3389/fimmu.2021.661204DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117219PMC
April 2021

Correction to "A Universal Fe/N Incorporated Graphdiyne for Printing Flexible Ferromagnetic Semiconducting Electronics".

J Phys Chem Lett 2021 May 12;12(19):4706. Epub 2021 May 12.

Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, P.R. China.

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http://dx.doi.org/10.1021/acs.jpclett.1c01477DOI Listing
May 2021

Circular RNA UBAP2 promotes the proliferation of prostate cancer cells via the miR-1244/MAP3K2 axis.

Oncol Lett 2021 Jun 21;21(6):486. Epub 2021 Apr 21.

Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang Uygur Autonomous Region 830054, P.R. China.

Prostate cancer (PCa) is a common male malignant disease with a high incidence, which can seriously affect the quality of life of patients. The survival rate of patients with PCa has improved to 98.6%; however, new insights for the molecular mechanism are still urgently required. Circular RNA (circ)UBAP2 is a tumor-associated circRNA that has been demonstrated to promote the progression of various types of cancer. CircUBAP2 has been demonstrated to be significantly upregulated in PCa, but its role in the progression of PCa remains unclear. The present study aimed to provide an improved understanding of the regulatory mechanism of circUBAP2 in PCa. circUBAP2 expression was identified to be upregulated in four PCa cell lines and clinical tissues by using reverse transcription-quantitative PCR analysis. Binding sites analysis and luciferase reporter gene assay indicated that the microRNA(miR)-1244/MAP3K2 axis was the target of circUBAP2. Gain-of-function assays revealed that circUBAP2 promoted the proliferation of PCa cells by sponging miR-1244 and promoting the MAP3K2 axis. The present findings may be essential for providing new strategies in the diagnosis and targeted therapy of PCa.
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http://dx.doi.org/10.3892/ol.2021.12747DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8100954PMC
June 2021

ITIH5, a p53-responsive gene, inhibits the growth and metastasis of melanoma cells by downregulating the transcriptional activity of KLF4.

Cell Death Dis 2021 May 2;12(5):438. Epub 2021 May 2.

Department of Gynecology, Cancer Hospital of China Medical University, Liaoning Cancer Hospital & Institute, Shenyang, China.

ITIH5, a member of the inter-α-trypsin inhibitory (ITI) gene family, acts as a putative tumour-suppressor gene in many cancers. However, its role and the regulatory mechanism in melanoma are still unclear. Here, we found that the expression of ITIH5 was decreased in melanoma tissues compared with normal skin tissues. Decreased expression of ITIH5 was correlated with clinicopathological features and predicted poor prognosis in patients with melanoma. Forced expression of ITIH5 significantly inhibited melanoma cell proliferation and metastasis in vitro and ex vivo while knockdown of ITIH5 expression enhanced the malignant behaviour of melanoma cells. In further mechanistic studies, we showed that p53 can directly bind to the promoter of ITIH5 and thus promotes transcription of ITIH5 in melanoma cells. Additionally, we found that ITIH5 interacted with Krüppel-like factor 4 (KLF4) and inhibited its transcriptional activity. Collectively, our data not only identified a tumour-suppressive role of ITIH5 in melanoma but also revealed that upregulation of ITIH5 by p53 suppressed melanoma cell growth and migration likely by downmodulating the transcriptional activity of KLF4.
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http://dx.doi.org/10.1038/s41419-021-03707-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8089095PMC
May 2021

Identification of crucial noncoding RNAs and mRNAs in hypertrophic scars via RNA sequencing.

FEBS Open Bio 2021 Jun 12;11(6):1673-1684. Epub 2021 May 12.

Department of Plastic and Reconstructive Surgery, The First Medical Center, Chinese PLA General Hospital, Beijing, China.

Hypertrophic scarring (HS) is a dermal fibroproliferative disorder characterized by excessive deposition of collagen and other extracellular matrix components. The aim of this study is to explore crucial long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) associated with HS and provide a better understanding of the molecular mechanism of HS. To investigate the lncRNA, circRNA and mRNA expression profiles, we performed RNA sequencing of human HS and normal skin tissues. After the identification of differentially expressed mRNAs (DEmRNAs), lncRNAs (DElncRNAs) and circRNAs (DEcircRNAs), we performed functional enrichment of DEmRNAs. Further on, we constructed DElncRNA/DEcircRNA-DEmRNA coexpression networks and competing endogenous RNA regulatory networks, and performed functional analyses of the DEmRNAs in the constructed networks. In total, 487 DEmRNAs, 92 DElncRNAs and 17 DEcircRNAs were identified. DEmRNAs were significantly enriched in processes such as collagen fibril organization, extracellular matrix-receptor interaction and the phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway. In addition, we detected 580 DElncRNA-DEmRNA and 505 DEcircRNA-DEmRNA coexpression pairs. The competing endogenous RNA network contained 18 circRNA-microRNA (miRNA) pairs, 18 lncRNA-miRNA pairs and 409 miRNA-mRNA pairs, including 10 circRNAs, 5 lncRNAs, 15 miRNAs and 160 mRNAs. We concluded that MIR503HG/hsa-miR-204-3p/ACAN, MIR503HG/hsa-miR-431-5p/TNFRSF9, MEG3/hsa-miR-6884-5p/ADAMTS14, AC000035.1-ADAMTS14 and hsa_circ_0069865-COMP/ADAM12 interaction pairs may play a central role in HS.
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http://dx.doi.org/10.1002/2211-5463.13167DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8167876PMC
June 2021

Off-Grid DOA Estimation Based on Circularly Fully Convolutional Networks (CFCN) Using Space-Frequency Pseudo-Spectrum.

Sensors (Basel) 2021 Apr 14;21(8). Epub 2021 Apr 14.

Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.

Low-frequency multi-source direction-of-arrival (DOA) estimation has been challenging for micro-aperture arrays. Deep learning (DL)-based models have been introduced to this problem. Generally, existing DL-based methods formulate DOA estimation as a multi-label multi-classification problem. However, the accuracy of these methods is limited by the number of grids, and the performance is overly dependent on the training data set. In this paper, we propose an off-grid DL-based DOA estimation. The backbone is based on circularly fully convolutional networks (CFCN), trained by the data set labeled by space-frequency pseudo-spectra, and provides on-grid DOA proposals. Then, the regressor is developed to estimate the precise DOAs according to corresponding proposals and features. In this framework, spatial phase features are extracted by the circular convolution calculation. The improvement in spatial resolution is converted to increasing the dimensionality of features by rotating convolutional networks. This model ensures that the DOA estimations at different sub-bands have the same interpretation ability and effectively reduce network model parameters. The simulation and semi-anechoic chamber experiment results show that CFCN-based DOA is superior to existing methods in terms of generalization ability, resolution, and accuracy.
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http://dx.doi.org/10.3390/s21082767DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8070975PMC
April 2021

Non-Isothermal Crystallization Kinetics of Poly(Ethylene Glycol)-Poly(l-Lactide) Diblock Copolymer and Poly(Ethylene Glycol) Homopolymer via Fast-Scan Chip-Calorimeter.

Polymers (Basel) 2021 Apr 4;13(7). Epub 2021 Apr 4.

School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China.

The non-isothermal crystallization kinetics of double-crystallizable poly(ethylene glycol)-poly(l-lactide) diblock copolymer (PEG-PLLA) and poly(ethylene glycol) homopolymer (PEG) were studied using the fast cooling rate provided by a Fast-Scan Chip-Calorimeter (FSC). The experimental data were analyzed by the Ozawa method and the Kissinger equation. Additionally, the total crystallization rate was represented by crystallization half time . The Ozawa method is a perfect success because secondary crystallization is inhibited by using fast cooling rate. The first crystallized PLLA block provides nucleation sites for the crystallization of PEG block and thus promotes the crystallization of the PEG block, which can be regarded as heterogeneous nucleation to a certain extent, while the method of the PEG block and PLLA block crystallized together corresponds to a one-dimensional growth, which reflects that there is a certain separation between the crystallization regions of the PLLA block and PEG block. Although crystallization of the PLLA block provides heterogeneous nucleation conditions for PEG block to a certain extent, it does not shorten the time of the whole crystallization process because of the complexity of the whole crystallization process including nucleation and growth.
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http://dx.doi.org/10.3390/polym13071156DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8038454PMC
April 2021