Publications by authors named "Jiang Tian"

267 Publications

Bifunctional Spatiotemporal Metasurfaces for Incident Angle-Tunable and Ultrafast Optically Switchable Electromagnetically Induced Transparency.

Small 2021 Apr 10:e2006489. Epub 2021 Apr 10.

Beijing Interdisciplinary Research Center, National University of Defense Technology, Beijing, 100010, China.

Advances in tunable metamaterials/metasurfaces facilitates their utilization in novel optical components, and lead to many breakthroughs in light tailoring by giving birth to diverse spatiotemporal dynamics. In the ascendant field of terahertz (THz) photonics, the ultrafast modulation is the fundamental process of technological advancements in high-speed wireless communications, sensing, and imaging. However, the current research efforts have been mainly devoted to studies of single functionality under the control of one stimulus, which has plateaued in terms of innovative new features. Here, building on the incident angle-induced C symmetry breaking of split ring pairs, we experimentally demonstrate extremely versatile, ultrafast THz switching behaviors at continuously alterable resonant states. The direction-controlled resonance hybridization provides another excellent degree of routing freedom, owing to its robustness, simplicity, and wide tunability. By leveraging such virtues, single LC mode and EIT-like resonance under normal and oblique incidence conditions are both effectively switched-off by means of photon injection. Considering the ultrashort lifetime of free carriers in MoSe crystal, the corresponding transient dynamics show an ultrafast recovery time within 700 ps. The strategy proposed here is a viable pathway for multidimensional THz wave manipulation, which gears up a crucial step for diversified functionalities in deployable metaphotonic devices.
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http://dx.doi.org/10.1002/smll.202006489DOI Listing
April 2021

pVHL promotes lysosomal degradation of YAP in lung adenocarcinoma.

Cell Signal 2021 Apr 3;83:110002. Epub 2021 Apr 3.

NHC Key Laboratory of Glycoconjugate Research, School of Basic Medical Sciences, Fudan University, Shanghai, China; Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China. Electronic address:

Yes-associated protein (YAP) is a vital transcriptional co-activator that activates cell proliferation and evasion of apoptosis for the promotion of tumorigenesis. The von Hippel-Lindau tumor suppressor protein (pVHL), as a critical component of E3 ubiquitin ligase, targets various substrates to regulate tumor progression. However, the precise molecular mechanisms of pVHL during tumorigenesis remain largely unclear. Herein, we found that there was a significant negative correlation between pVHL and YAP at protein level in the TCGA-LUAD dataset and our cohort. Over-expression of pVHL decreased YAP protein expression and reduced its transcriptional activity. Further study indicated that pVHL did not affect YAP mRNA level but decreased YAP protein stability in a lysosome-dependent manner. In addition, the pVHL-mediated degradation of YAP inhibited cellular proliferation, migration, and enhanced chemosensitivity to cisplatin in lung adenocarcinoma cells. Interestingly, the pVHL-mediated YAP degradation was blocked by elevated O-GlcNAcylation. Collectively, our findings demonstrate that pVHL modulates the lysosomal degradation of YAP, and may provide more clues to better understanding the tumor suppressive effects of pVHL.
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http://dx.doi.org/10.1016/j.cellsig.2021.110002DOI Listing
April 2021

Cardiac Oxidative Signaling and Physiological Hypertrophy in the Na/K-ATPase α1α2 Mouse Model of High Affinity for Cardiotonic Steroids.

Int J Mol Sci 2021 Mar 27;22(7). Epub 2021 Mar 27.

Marshall Institute for Interdisciplinary Research, Huntington, WV 25703, USA.

The Na/K-ATPase is the specific receptor for cardiotonic steroids (CTS) such as ouabain and digoxin. At pharmacological concentrations used in the treatment of cardiac conditions, CTS inhibit the ion-pumping function of Na/K-ATPase. At much lower concentrations, in the range of those reported for endogenous CTS in the blood, they stimulate hypertrophic growth of cultured cardiac myocytes through initiation of a Na/K-ATPase-mediated and reactive oxygen species (ROS)-dependent signaling. To examine a possible effect of endogenous concentrations of CTS on cardiac structure and function in vivo, we compared mice expressing the naturally resistant Na/K-ATPase α1 and age-matched mice genetically engineered to express a mutated Na/K-ATPase α1 with high affinity for CTS. In this model, total cardiac Na/K-ATPase activity, α1, α2, and β1 protein content remained unchanged, and the cardiac Na/K-ATPase dose-response curve to ouabain shifted to the left as expected. In males aged 3-6 months, increased α1 sensitivity to CTS resulted in a significant increase in cardiac carbonylated protein content, suggesting that ROS production was elevated. A moderate but significant increase of about 15% of the heart-weight-to-tibia-length ratio accompanied by an increase in the myocyte cross-sectional area was detected. Echocardiographic analyses did not reveal any change in cardiac function, and there was no fibrosis or re-expression of the fetal gene program. RNA sequencing analysis indicated that pathways related to energy metabolism were upregulated, while those related to extracellular matrix organization were downregulated. Consistent with a functional role of the latter, an angiotensin-II challenge that triggered fibrosis in the α1α2 mouse failed to do so in the α1α2. Taken together, these results are indicative of a link between circulating CTS, Na/K-ATPase α1, ROS, and physiological cardiac hypertrophy in mice under baseline laboratory conditions.
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http://dx.doi.org/10.3390/ijms22073462DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8036649PMC
March 2021

All-Inorganic Quantum Dot Light-Emitting Diodes with Suppressed Luminance Quenching Enabled by Chloride Passivated Tungsten Phosphate Hole Transport Layers.

Small 2021 Mar 30:e2100030. Epub 2021 Mar 30.

Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai, 200072, China.

Although excellent performance such as high efficiency and stability have been achieved in quantum dot (QD)-based light-emitting diodes (QLEDs) possessing an organic/inorganic hybrid device structure, the highly expected all-inorganic QLEDs remain at the bottleneck stage in recent years, resulting from the luminance quenching of QDs caused by inorganic hole transport layer (HTL) and unbalanced charge injection due to large energy barrier for injecting holes from HTL to QDs. Here, it is reported that the solution-processed inorganic environmentally friendly chloride (Cl)-passivated tungsten phosphate (Cl@TPA) films serve as HTL. The incorporation of Cl in TPA effectively passivates the oxygen vacancies, which not only avoids the luminescence quenching of QDs by reducing carrier concentration but also facilitates the hole injection from HTL to QDs with a favorable electronic band alignment, thus achieving the record external quantum efficiency of ≈9.27%, among all previous reports about all-inorganic QLEDs. Most importantly, the resulting all-inorganic QLEDs with Cl@TPA exhibit a substantial improvement in the operational lifetime (T  > 10 h under an initial luminance of 100 cd m ), which is almost 30-fold higher than the devices with TPA HTL. This work furnishes a promising strategy for highly efficient and stable QLEDs based on inorganic device structure.
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http://dx.doi.org/10.1002/smll.202100030DOI Listing
March 2021

Fermi Velocity Reduction of Dirac Fermions around the Brillouin Zone Center in In Se -Bilayer Graphene Heterostructures.

Adv Mater 2021 Mar 19:e2007503. Epub 2021 Mar 19.

Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen, 518055, China.

Emergent phenomena such as unconventional superconductivity, Mott-like insulators, and the peculiar quantum Hall effect in graphene-based heterostructures are proposed to stem from the superlattice-induced renormalization of (moiré) Dirac fermions at the graphene Brillouin zone corners. Understanding the corresponding band structure commonly demands photoemission spectroscopy with both sub-meV resolution and large-momentum coverage, beyond the capability of the current state-of-the-art. Here the realization of moiré Dirac cones around the Brillouin zone center in monolayer In Se /bilayer graphene heterostructure is reported. The renormalization is evidenced by reduced Fermi velocity (≈23%) of the moiré Dirac cones and the reshaped Dirac point at the Γ point where they intersect. While there have been many theoretical predictions and much indirect experimental evidence, the findings here are the first direct observation of Fermi velocity reduction of the moiré Dirac cones. These features suggest strong In Se /graphene interlayer coupling, which is comparable with that in twisted bilayer graphene. The strategy expands the choice of materials in the heterostructure design and stimulates subsequent broad investigations of emergent physics at the sub-meV energy scale.
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http://dx.doi.org/10.1002/adma.202007503DOI Listing
March 2021

Metabolomics reveals the inhibition on phosphorus assimilation in Chlorella vulgaris F1068 exposed to AgNPs.

Sci Total Environ 2021 May 23;770:145362. Epub 2021 Jan 23.

Department of Environment, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China. Electronic address:

Phosphorus removal by algae-based biotechnology can be achieved through algal assimilation, surface adsorption, or abiotic precipitation. However, there are still unavailable how these phosphorus removal processes were affected by nanoparticles in wastewater. Here, we employed a non-targeted metabolomic approach to reveal the impact of silver nanoparticles (AgNPs) on the phosphorus assimilation by a unicellular green alga Chlorella vulgaris F1068 (C. vulgaris F1068). Results showed that AgNPs mostly inhibited total phosphorus (TP) removal by the algal assimilation, with TP removal efficiency being reduced by 66.2% (with 0.20 mg/L AgNPs) of the control (without AgNPs). Metabolomics analysis also indicated that AgNPs disturbed metabolic responses related to phosphorus assimilation. AgNPs inhibited phospholipid metabolism which included inositol phosphate metabolism and phosphatidylinositol signaling system (downregulation of glycerol-3-phosphate and myo-inositol, as well as upregulation of serine). Metabolites related to phosphorus assimilation products were impacted through downregulation of guanine, glutamine, alanine, and aspartic acid, as well as upregulation of succinic acid, thereby impeding the algal assimilation of phosphorus. Moreover, perturbation of glutathione metabolism induced by oxidative stress stimulated the alteration of membrane state (upregulation of glycine). These findings contribute to a molecular-scale perspective of nanoparticles on algae-based biotechnology in phosphorus removal.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145362DOI Listing
May 2021

Roles of Phosphate Solubilizing Microorganisms from Managing Soil Phosphorus Deficiency to Mediating Biogeochemical P Cycle.

Biology (Basel) 2021 Feb 17;10(2). Epub 2021 Feb 17.

Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.

Phosphorus (P) is a vital element in biological molecules, and one of the main limiting elements for biomass production as plant-available P represents only a small fraction of total soil P. Increasing global food demand and modern agricultural consumption of P fertilizers could lead to excessive inputs of inorganic P in intensively managed croplands, consequently rising P losses and ongoing eutrophication of surface waters. Despite phosphate solubilizing microorganisms (PSMs) are widely accepted as eco-friendly P fertilizers for increasing agricultural productivity, a comprehensive and deeper understanding of the role of PSMs in P geochemical processes for managing P deficiency has received inadequate attention. In this review, we summarize the basic P forms and their geochemical and biological cycles in soil systems, how PSMs mediate soil P biogeochemical cycles, and the metabolic and enzymatic mechanisms behind these processes. We also highlight the important roles of PSMs in the biogeochemical P cycle and provide perspectives on several environmental issues to prioritize in future PSM applications.
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http://dx.doi.org/10.3390/biology10020158DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7922199PMC
February 2021

Does non-COVID-19 lung lesion help? investigating transferability in COVID-19 CT image segmentation.

Comput Methods Programs Biomed 2021 Apr 23;202:106004. Epub 2021 Feb 23.

Institute of Computing Technology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, China; Lenovo Corporate Research & Development, Lenovo Ltd., Beijing, China. Electronic address:

Background And Objective: Coronavirus disease 2019 (COVID-19) is a highly contagious virus spreading all around the world. Deep learning has been adopted as an effective technique to aid COVID-19 detection and segmentation from computed tomography (CT) images. The major challenge lies in the inadequate public COVID-19 datasets. Recently, transfer learning has become a widely used technique that leverages the knowledge gained while solving one problem and applying it to a different but related problem. However, it remains unclear whether various non-COVID19 lung lesions could contribute to segmenting COVID-19 infection areas and how to better conduct this transfer procedure. This paper provides a way to understand the transferability of non-COVID19 lung lesions and a better strategy to train a robust deep learning model for COVID-19 infection segmentation.

Methods: Based on a publicly available COVID-19 CT dataset and three public non-COVID19 datasets, we evaluate four transfer learning methods using 3D U-Net as a standard encoder-decoder method. i) We introduce the multi-task learning method to get a multi-lesion pre-trained model for COVID-19 infection. ii) We propose and compare four transfer learning strategies with various performance gains and training time costs. Our proposed Hybrid-encoder Learning strategy introduces a Dedicated-encoder and an Adapted-encoder to extract COVID-19 infection features and general lung lesion features, respectively. An attention-based Selective Fusion unit is designed for dynamic feature selection and aggregation.

Results: Experiments show that trained with limited data, proposed Hybrid-encoder strategy based on multi-lesion pre-trained model achieves a mean DSC, NSD, Sensitivity, F1-score, Accuracy and MCC of 0.704, 0.735, 0.682, 0.707, 0.994 and 0.716, respectively, with better genetalization and lower over-fitting risks for segmenting COVID-19 infection.

Conclusions: The results reveal the benefits of transferring knowledge from non-COVID19 lung lesions, and learning from multiple lung lesion datasets can extract more general features, leading to accurate and robust pre-trained models. We further show the capability of the encoder to learn feature representations of lung lesions, which improves segmentation accuracy and facilitates training convergence. In addition, our proposed Hybrid-encoder learning method incorporates transferred lung lesion features from non-COVID19 datasets effectively and achieves significant improvement. These findings promote new insights into transfer learning for COVID-19 CT image segmentation, which can also be further generalized to other medical tasks.
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http://dx.doi.org/10.1016/j.cmpb.2021.106004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7899930PMC
April 2021

A versatile chitosan nanogel capable of generating AgNPs in-situ and long-acting slow-release of Ag for highly efficient antibacterial.

Carbohydr Polym 2021 Apr 16;257:117636. Epub 2021 Jan 16.

College of Materials Science and Engineering, Nanjing Tech University, Nanjing, 211816, PR China. Electronic address:

Development of multifunctional antibacterial agent with long-lasting antibacterial activity and biofilm ablation performance is significant for the effective treatment of bacterial infections. Here, by utilizing the electrostatic interaction between sulfonated chitosan (SCS) and Ag and chitosan (CS), and the sodium borohydride reduction method, a versatile antibacterial agent (AgNPs@CS/SCS) capable of generating silver nanoparticles (AgNPs) in-situ and long-acting slow-release Ag was developed. AgNPs@CS/SCS has a good physiological stability and can long-acting slow-release of Ag due to the pH-dependent Ag release behavior of AgNPs. Noteworthy, AgNPs@CS/SCS can exert both excellent short- and long-term antibacterial and biofilm ablation activity. Importantly, it also exhibits superior antibacterial activity in the treatment of implant infections, accompanied by good biocompatibility. Together, this study suggest that AgNPs@CS/CSC is indeed a versatile antibacterial agent, and is expected to provide an effective treatment modality for implant infections in the clinic settings.
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http://dx.doi.org/10.1016/j.carbpol.2021.117636DOI Listing
April 2021

Contrast-Enhanced Ultrasound Assessment of Renal Parenchymal Perfusion in Patients with Atherosclerotic Renal Artery Stenosis to Predict Renal Function Improvement After Revascularization.

Int J Gen Med 2020 31;13:1713-1721. Epub 2020 Dec 31.

Department of General Surgery, Tongji Hospital of Tongji University, Shanghai, People's Republic of China.

Background: Identifying patients with atherosclerotic renal artery stenosis (ARAS) who will be improved in renal function after percutaneous transluminal renal artery stenting (PTRAS) is crucial since most patients show no worthwhile benefit of PTRAS. Although the assessment of renal parenchymal perfusion is useful for the identification, few studies predict the renal functional improvement by evaluating the characteristics of renal perfusion.

Objective: The aim of this study was to assess the renal parenchymal perfusion in ARAS patients with contrast-enhanced ultrasonography (CEUS) and predict the benefits of renal function after PTRAS utilizing time-intensity curve (TIC) parameters.

Methods: Thirty-eight kidneys in 30 ARAS patients received PTRAS in this study. They were divided into moderate stenosis group (n=25) and severe stenosis group (n=13) and mild dysfunction group (n=14) and moderate dysfunction group (n=24) according to the degree of renal stenosis and radioisotope glomerular filtration rate (rGFR). The baseline assessment of renal function and renal parenchymal perfusion were performed for all patients. rGFR was repeated to evaluate the renal outcome at 4 months after PTRAS. The outcome of PTRAS was classified as improved, stable, or deteriorated compared to the baseline. Time-intensity curve (TIC) parameters obtained from CEUS were analyzed to evaluate the predictive accuracy.

Results: TIC parameters (AUC and PI) were positively correlated with renal function (r=0.617, 0.663; P<0.05) but weakly and negatively correlated with the stenosis (r=-0.360, -0.435; P<0.05). Baseline rGFR was not accurate in predicting improved renal function after PTRAS (0.670). The accuracy of the combined prediction model of baseline AUC and PI (0.889) was higher than the individual indicators (baseline AUC: 0.855 and PI: 0.782).

Conclusion: CEUS could accurately assess renal parenchymal perfusion and identify ARAS patients with potential benefit after PTRAS. The combination of TIC parameters (AUC and PI) is valuable in the prediction of improved renal function after PTRAS.
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http://dx.doi.org/10.2147/IJGM.S293316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7781108PMC
December 2020

Optimization of a -Coumaric Acid Biosensor System for Versatile Dynamic Performance.

ACS Synth Biol 2021 01 30;10(1):132-144. Epub 2020 Dec 30.

School of Chemical, Materials, and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, Georgia 30602, United States.

Metabolic engineering is a promising approach for the synthesis of valuable compounds. Transcriptional factor-based biosensors are efficient tools to regulate the metabolic pathway dynamically. Here, we engineered the -coumaric acid responsive regulator PadR from . We found that and , two previously uncharacterized components in the sensor system, showed positive impacts on the regulation of PadR-P sensor system, mostly on assisting the release of the repression by PadR. By site directed PadR engineering, we obtained two mutants, K64A and H38A, which exhibited increased dynamic range and superior sensitivity. To increase the promoter strength of the sensor system and investigate whether the PadR binding boxes can function in a "plug-and-play" manner, a series of hybrid promoters were constructed. Four of them, P1, P2, P7, and P9, showed increased strength compared to P and can be regulated by PadR and -coumaric acid. The PadR variants and hybrid promoters obtained in this paper would expand the applicability of this sensor system in future metabolic engineering research.
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http://dx.doi.org/10.1021/acssynbio.0c00500DOI Listing
January 2021

B4GALNT1 promotes progression and metastasis in lung adenocarcinoma through JNK/c-Jun/Slug pathway.

Carcinogenesis 2020 Dec 24. Epub 2020 Dec 24.

Department of Thoracic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China.

Lung adenocarcinoma (LUAD) is one of the most common types of cancer and has a low survival rate. β-1,4-N-acetyl galactosaminyltransferase 1 (B4GALNT1), which is involved in the synthesis of complex gangliosides, is highly expressed in the progression of various cancers. This study aimed to elucidate the biological functions of B4GALNT1 in LUAD progression and metastasis. We observed that B4GALNT1 overexpression showed enhanced cell migration and invasion in vitro, and promoted tumor metastasis, with reduced survival in mice. Mechanistically, B4GALNT1 regulated metastatic potential of LUAD through activating the JNK/c-Jun/Slug pathway, and with the form of its enzymatic activity. Clinical samples confirmed that B4GALNT1 expression was upregulated in LUAD, and B4GALNT1 was correlated with c-Jun/Slug expression, lymph node involvement, advanced clinical stage, and reduced overall survival. Collectively, our results suggest that B4GALNT1 promotes progression and metastasis of LUAD through activating JNK/c-Jun/Slug signaling, and with the form of its enzymatic activity.
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http://dx.doi.org/10.1093/carcin/bgaa141DOI Listing
December 2020

A strategic expression method of miR-29b and its anti-fibrotic effect based on RNA-sequencing analysis.

PLoS One 2020 17;15(12):e0244065. Epub 2020 Dec 17.

Joan C. Edwards School of Medicine, Department of Biomedical Sciences, Marshall University, Huntington, West Virginia, United States of America.

Tissue fibrosis is a significant health issue associated with organ dysfunction and failure. Increased deposition of collagen and other extracellular matrix (ECM) proteins in the interstitial area is a major process in tissue fibrosis. The microRNA-29 (miR-29) family has been demonstrated as anti-fibrotic microRNAs. Our recent work showed that dysregulation of miR-29 contributes to the formation of cardiac fibrosis in animal models of uremic cardiomyopathy, whereas replenishing miR-29 attenuated cardiac fibrosis in these animals. However, excessive overexpression of miR-29 is a concern because microRNAs usually have multiple targets, which could result in unknown and unexpected side effect. In the current study, we constructed a novel Col1a1-miR-29b vector using collagen 1a1 (Col1a1) promoter, which can strategically express miR-29b-3p (miR-29b) in response to increased collagen synthesis and reach a dynamic balance between collagen and miR-29b. Our experimental results showed that in mouse embryonic fibroblasts (MEF cells) transfected with Col1a1-miR-29b vector, the miR-29b expression is about 1000 times less than that in cells transfected with CMV-miR-29b vector, which uses cytomegalovirus (CMV) as a promoter for miR-29b expression. Moreover, TGF-β treatment increased the miR-29b expression by about 20 times in cells transfected with Col1a1-miR-29b, suggesting a dynamic response to fibrotic stimulation. Western blot using cell lysates and culture media demonstrated that transfection of Col1a1-miR-29b vector significantly reduced TGF-β induced collagen synthesis and secretion, and the effect was as effective as the CMV-miR-29b vector. Using RNA-sequencing analysis, we found that 249 genes were significantly altered (180 upregulated and 69 downregulated, at least 2-fold change and adjusted p-value <0.05) after TGF-β treatment in MEF cells transfected with empty vector. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis using GAGE R-package showed that the top 5 upregulated pathways after TGF-β treatment were mostly fibrosis-related, including focal adhesion, ECM reaction, and TGF-β signaling pathways. As expected, transfection of Col1a1-miR-29b or CMV-miR-29b vector partially reversed the activation of these pathways. We also analyzed the expression pattern of the top 100 miR-29b targeting genes in these cells using the RNA-sequencing data. We identified that miR-29b targeted a broad spectrum of ECM genes, but the inhibition effect is mostly moderate. In summary, our work demonstrated that the Col1a1-miR-29b vector can be used as a dynamic regulator of collagen and other ECM protein expression in response to fibrotic stimulation, which could potentially reduce unnecessary side effect due to excessive miR-29b levels while remaining an effective potential therapeutic approach for fibrosis.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244065PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7746150PMC
March 2021

Enhanced Terahertz Radiation by Efficient Spin-to-Charge Conversion in Rashba-Mediated Dirac Surface States.

Nano Lett 2021 Jan 17;21(1):60-67. Epub 2020 Dec 17.

National Innovation Institute of Defense Technology, Academy of Military Sciences PLA China, Beijing 100010, China.

The enhancement of terahertz (THz) radiation is of extreme significance for the realization of the THz probe and imaging. However, present THz technologies are far from being enough to realize high-performance and room-temperature THz sources. Fortunately, topological insulators (TIs), with spin-momentum-locked Dirac surface states, are expected to exhibit a high terahertz emission efficiency. In this work, the novel concept of a Rashba-state-enhanced spintronic THz emitter is demonstrated on the basis of ferromagnet/heavy metal/topological insulator (FM/HM/TI) heterostructure. We find that the THz emission intensity changes as a function of HM interlayer thickness, and a 1.98 times higher intensity compared to that of FM/TI can be achieved when a meticulously designed thickness of the HM layer is inserted. The improvement of terahertz radiation is ascribed to the additive effect of Rashba splitting and topological surface states at the HM/TI interface. These results offer new possibilities for realizing spintronic THz emitters in TI-based magnetic heterostructures.
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http://dx.doi.org/10.1021/acs.nanolett.0c03079DOI Listing
January 2021

An Alternating Irradiation Strategy-Driven Combination Therapy of PDT and RNAi for Highly Efficient Inhibition of Tumor Growth and Metastasis.

Adv Healthc Mater 2020 Dec 13:e2001850. Epub 2020 Dec 13.

National Engineering Research Center for Biomaterials, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan, 610065, P. R. China.

Hypoxia and hypoxia induced overexpression of vascular endothelial growth factor (VEGF) not only seriously affects the treatment effects of photodynamic therapy (PDT) but also promotes tumor metastasis. Herein, an alternating irradiation strategy (referred to as alternate use of low/high dose of light [ALHDL] irradiation)-driven combination therapy of PDT and RNA interference (RNAi) is developed to synergistically inhibit tumor growth and metastasis. A cationic amphipathic peptide (ALS) served as a carrier in the co-delivery system of photochlor (HPPH) and siVEGF (ALSH/siVEGF). At the beginning of ALHDL-driven ALSH/siVEGF treatment, short-term LDL irradiation can facilitate the tumor penetration, cellular uptake, and endosome escape of ALSH/siVEGF. Moreover, accompanied by HDL-mediated rapid cell apoptosis and LDL-mediated efficient VEGF silencing, the joint use of PDT and RNAi achieved remarkable antitumor effects both in vitro and in vivo. Importantly, benefited from the excellent performance of ALHDL in slowing the rapid deterioration of the anoxic environment of tumors, and ALSH/siVEGF treatment-mediated highly improved VEGF silencing efficacy and inhibitory effect on angiogenesis, the liver and lung metastases of HeLa cells have been successfully suppressed. Together, this study clearly indicates that ALHDL-driven combination therapy of PDT and RNAi is a highly effective modality for inhibition of tumor growth and metastasis.
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http://dx.doi.org/10.1002/adhm.202001850DOI Listing
December 2020

The anti-inflammatory potential of protein-bound anthocyanin compounds from purple sweet potato in LPS-induced RAW264.7 macrophages.

Food Res Int 2020 11 1;137:109647. Epub 2020 Sep 1.

Yun-Hong Group Co. Ltd, 430206 Wuhan, China.

Interaction between proteins and anthocyanins spontaneously occurs in most of food systems, resulting the formation of protein-bound anthocyanin compounds, and the interactions between anthocyanins and proteins might impact activity of anthocyanins. In the present study, predominant anthocyanin compounds in free anthocyanin compounds from purple sweet potato (FAC-PSP) were identified and protein in protein-bound anthocyanin compounds from purple sweet potato (p-BAC-PSP) were assayed. Furthermore, the effects of pre-treatment of cells with p-BAC-PSP and FAC-PSP on cell viability, inflammatory mediators, reactive oxygen species, cytokines and gene expression were determined in LPS-induced RAW264.7 macrophages. The results revealed 17 protein groups and pigmented polymers in p-BAC-PSP, and 3 different anthocyanins in FAC-PSP. There were no significant differences (p > 0.05) in the anti-inflammatory effect between p-BAC-PSP and FAC-PSP. p-BAC-PSP significantly (p < 0.05) reduced the expression of inducible nitric oxide synthases (iNOS) and tumor necrosis factor-α (TNF-α) in RAW264.7 cells stimulated by LPS, thereby suppressing the release of NO and TNF-α. Moreover, p-BAC-PSP markedly inhibited LPS-induced reactive oxygen species (ROS) accumulation via heme oxygenase-1 (HO-1) and factor erythroid 2-related factor 2 (Nrf2). Further analysis revealed that p-BAC-PSP suppressed both LPS-induced activation of c-Jun N-terminal kinase (JNK), and the nuclear translocation of activator protein-1 (AP-1). Our research suggested that naturally occurring p-BAC-PSP has the potential to be a dietary supplement with anti-inflammatory effect, which would meaningful from the actual utilization points of view for purple sweet potato production industry.
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http://dx.doi.org/10.1016/j.foodres.2020.109647DOI Listing
November 2020

Sub-100 fs all-fiber broadband electro-optic optical frequency comb at 1.5 µm.

Opt Express 2020 Nov;28(23):34761-34771

A sub-100 fs all-fiber broadband optical frequency comb seeded from a 12.5 GHz electro-optic modulated pulse is presented. Combining pulse reshaping, nonlinear mixing with dispersion compensation processes, a frequency comb with the main pulse width of 86 fs was achieved. The frequency comb has a 6 dB spectral bandwidth spanning over 150 nm which corresponding to more than 1500 comb tones. The measured average power of the broadband comb is over 550 mW, and the calculated average power of each comb line is roughly -4 dBm. To illustrate the whole spectral broadening process, a numerical investigation was also brought out, showing a very good match with the experiments. With a delayed self-heterodyne interferometer, the evolutions of the seed comb linewidths and the broadened comb linewidths were measured revealing the same parabolic trend. Specifically, the linewidths of the 20 seed comb lines are less than 10 kHz, while the linewidths of the 400 broadened comb lines are less than 1 MHz. The results also indicate that the nonlinear mixing led to an accumulation of the phase noise with respect to the comb line number, indicating that a low phase noise RF source or phase locking technique is essential to produce ultra-low phase noise broadband electro-optic combs.
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http://dx.doi.org/10.1364/OE.409838DOI Listing
November 2020

Distinctive Interfacial Charge Behavior and Versatile Photoresponse Performance in Isotropic/Anisotropic WS/ReS Heterojunctions.

ACS Appl Mater Interfaces 2020 Nov 12;12(47):53475-53483. Epub 2020 Nov 12.

College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, P. R. China.

Van der Waals (vdWs) heterostructures based on in-plane isotropic/anisotropic 2D-layered semiconducting materials have recently received wide attention because of their unique interlayer coupling properties and hold a bright future as building blocks for advanced photodetectors. However, a fundamental understanding of charge behavior inside this kind of heterostructure in the photoexcited state remains elusive. In this work, we carry out a systematic investigation into the photoinduced interfacial charge behavior in type-II WS/ReS vertical heterostructures via polarization-dependent pump-probe microscopy. Benefiting from the distinctive (ultrafast and anisotropic) charge-transfer mechanisms, the photodetector based on the WS/ReS heterojunction displays more superior optoelectronic properties compared to its constituents with diverse functionalities including moderate photoresponsivity, polarization sensitivity, and fast photoresponse speed. Additionally, this device can function as a self-driven photodetector without the external bias. These results of our work tangibly corroborate the intriguing interlayer interaction in in-plane isotropic/anisotropic heterostructures and are expected to shed light on designing balanced-performance multifunctional optoelectrical devices.
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http://dx.doi.org/10.1021/acsami.0c14886DOI Listing
November 2020

Electrochemical determination of artemisinin based on signal inhibition for the reduction of hemin.

Anal Bioanal Chem 2021 Jan 3;413(2):565-576. Epub 2020 Nov 3.

Anhui Key Laboratory of Chemo-Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, Anhui, China.

A novel electrochemical sensor was constructed for the determination of artemisinin (ART) based on the inhibition of redox for hemin caused by ART. As far as we know, this strategy for ART determination may be proposed for the first time. In this work, untreated multi-walled carbon nanotubes were cast on the glassy carbon electrode (GCE) as conductive carrier. We prepared a bimetallic organic framework named FeGd-MOF and combined it with hemin by a simple physical mixed method. Then, we fabricated the working electrode by layer-by-layer modification and immobilization. The sensor measured by the differential pulse voltammetry (DPV) technique had calibration curves for the determination of ART, which was 0.3-350 μM with the correlation coefficient R = 0.9998. Furthermore, the obtained linear range could be practically used in real sample analysis such as dried leaves of Artemisia apiacea. Under the optimized condition, the electrochemical sensor exhibited high sensitivity, good stability, and excellent anti-interference performance. The limit of detection (LOD) for this sensor was 0.17 μM (signal to noise ratio, S/N = 3), which was much lower than that for some other reported electrochemical sensors. The recovery rates were in the range of 99.54-104.34% in real samples, indicating that the sensor had good repetition and high accuracy. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-020-03028-2DOI Listing
January 2021

Intracellular Metabolomics Switching Alters Extracellular Acid Production and Insoluble Phosphate Solubilization Behavior in .

Metabolites 2020 Oct 31;10(11). Epub 2020 Oct 31.

Department of Environment, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.

This research aims to understand the precise intracellular metabolic processes of how microbes solubilize insoluble phosphorus (Insol-P) to increase bio-available P. Newly isolated PSF-4 exhibited outstanding tricalcium phosphate (TP) and iron phosphate (IP) solubilization performance-as manifested by microbial growth and the secretion of low-molecular-weight organic acids (LMWOAs). Untargeted metabolomics approach was employed to assess the metabolic alterations of 73 intracellular metabolites induced by TP and IP compared with soluble KHPO in . Based on the changes of intracellular metabolites, it was concluded that (i) the enhanced intracellular glyoxylate and carbohydrate metabolisms increased the extracellular LMWOAs production; (ii) the exposure of Insol-P poses potential effects to in destructing essential cellular functions, affecting microbial growth, and disrupting amino acid, lipid, and nucleotide metabolisms; and (iii) the intracellular amino acid utilization played a significant role to stimulate microbial growth and the extracellular LMWOAs biosynthesis.
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http://dx.doi.org/10.3390/metabo10110441DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692655PMC
October 2020

Determination of hydrogen peroxide released from cancer cells by a Fe-Organic framework/horseradish peroxidase-modified electrode.

Anal Chim Acta 2020 Oct 25;1135:132-141. Epub 2020 Sep 25.

Anhui Key Laboratory of Chemo-Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241000, PR China. Electronic address:

Multi-walled carbon nanotubes (MWCNTs) were used as conductive carrier on the glassy carbon electrode (GCE), and the hybrid of metal organic framework [NH-MIL-53(Fe)] and horseradish peroxidase (HRP) was prepared by simple physical mechanical mixture. The GCE modified by the above material with immobilization, namely NH-MIL-53(Fe)/HRP/MWCNTs/GCE, was used to construct an electrochemical biosensor toward HO. The results indicated that the addition of NH-MIL-53(Fe) had a good synergistic effect on the electron transfer of HRP and the detection of HO. Under the optimized condition, the biosensor exhibited excellent electrochemical performances such as low detection limit, high sensitivity, good stability and so on. The HO biosensor showed two linear ranges of 0.1-1 μM and 1-600 μM with a calculated detection limit of 0.028 μM (signal-to-noise ratio, S/N = 3). In addition, the stability of the hybrid of NH-MIL-53(Fe) and HRP were discussed by SEM, XRD and UV-vis methods. Furthermore, the reported biosensors were practically used in direct detection of HO released from HeLa and HepG2 cells successfully. Thus, this work provides a new strategy to fabricate electrochemical biosensors using MOFs and biomolecules.
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http://dx.doi.org/10.1016/j.aca.2020.09.040DOI Listing
October 2020

New Insight into Carboxylic Acid Metabolisms and pH Regulations During Insoluble Phosphate Solubilisation Process by Penicillium oxalicum PSF-4.

Curr Microbiol 2020 Dec 15;77(12):4095-4103. Epub 2020 Oct 15.

Department of Environment, College of Environment and Resources, Xiangtan University, Xiangtan, People's Republic of China.

Phosphate solubilising fungi (PSF) play an important role in increasing phosphorus (P) bioavailability and the fertility of soil. However, the mechanism by which PSF solubilise insoluble P using carboxylic acid is not fully understood. In this study, Penicillium oxalicum PSF-4 was isolated and shown to have satisfactory solubilisation performance towards tricalcium phosphate (TP) and iron phosphate (IP). In treatments with TP or IP, the soluble P (P) concentrations were positively correlated with the carboxyl groups in organic acids but negatively correlated with the pK of insoluble P sources and pH. Additionally, the compositions of the organic acids (considering the lowest pK value for acids with several pKs) were remarkably different between the treatments: oxalic (pK = 1.27), malic (pK = 3.46), and formic (pK = 3.75) acids in TP treatments (maximum 381 mg/L); and lactic (pK = 3.85), gluconic (pK = 3.86), and citric (pK = 3.12) acids in IP treatments (maximum 1634 mg/L). The addition of H without P. oxalicum PSF-4 inoculation markedly improved P concentrations. The above results offer new insights that the pK of P sources, compositions of carboxylic acids, and pH regulation are the key factors influencing P solubilisation of different insoluble P sources.
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http://dx.doi.org/10.1007/s00284-020-02238-2DOI Listing
December 2020

The state of the art in kidney and kidney tumor segmentation in contrast-enhanced CT imaging: Results of the KiTS19 challenge.

Med Image Anal 2021 01 2;67:101821. Epub 2020 Oct 2.

University of Minnesota, Minneapolis, United States.

There is a large body of literature linking anatomic and geometric characteristics of kidney tumors to perioperative and oncologic outcomes. Semantic segmentation of these tumors and their host kidneys is a promising tool for quantitatively characterizing these lesions, but its adoption is limited due to the manual effort required to produce high-quality 3D segmentations of these structures. Recently, methods based on deep learning have shown excellent results in automatic 3D segmentation, but they require large datasets for training, and there remains little consensus on which methods perform best. The 2019 Kidney and Kidney Tumor Segmentation challenge (KiTS19) was a competition held in conjunction with the 2019 International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) which sought to address these issues and stimulate progress on this automatic segmentation problem. A training set of 210 cross sectional CT images with kidney tumors was publicly released with corresponding semantic segmentation masks. 106 teams from five continents used this data to develop automated systems to predict the true segmentation masks on a test set of 90 CT images for which the corresponding ground truth segmentations were kept private. These predictions were scored and ranked according to their average Sørensen-Dice coefficient between the kidney and tumor across all 90 cases. The winning team achieved a Dice of 0.974 for kidney and 0.851 for tumor, approaching the inter-annotator performance on kidney (0.983) but falling short on tumor (0.923). This challenge has now entered an "open leaderboard" phase where it serves as a challenging benchmark in 3D semantic segmentation.
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http://dx.doi.org/10.1016/j.media.2020.101821DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7734203PMC
January 2021

Lactate-enhanced-qSOFA (LqSOFA) score is superior to the other four rapid scoring tools in predicting in-hospital mortality rate of the sepsis patients.

Ann Transl Med 2020 Aug;8(16):1013

Editorial Board of Journal of Sichuan University (Medical Science Edition), Chengdu, China.

Background: The rising prevalence of early therapy for sepsis has led to the demand for rapid risk-stratification tools that can estimate the risk of in-hospital mortality for sepsis patients and the need for intensive care unit (ICU) admission. A robust risk-stratification tool is crucial for in-time sepsis treatment. This study aimed to compare the abilities of five rapid scoring systems, i.e., LqSOFA score, qSOFA score, SIRS, MEDS, and MEWS, in predicting the mortality in hospital and ICU admission for sepsis patients.

Methods: A retrospective observational clinical study was conducted in West China Hospital. Our cases included all patients admitted to the hospital with a diagnosis of sepsis (sepsis-3). We calculated five rapid prediction scores for the enrolled cases. We then compared each rapid score's ability to predict in-hospital mortality and ICU admission.

Results: A total of 821 of mixed sepsis patients by sepsis-3 definition were included. The all-cause hospital mortality rate was 21.1%. The LqSOFA score presented the most significant discrimination with an area under the receiver operating characteristic curve (AUC) of 0.751. The AUC of the LqSOFA score for mortality in the hospital was significantly higher than qSOFA (AUC 0.717), SIRS (AUC 0.704), MEDS (AUC 0.670), and MEWS (AUC 0.685).

Conclusions: LqSOFA is a superior prognostic tool for predicting mortality in the hospital. It may provide more exact information for hospital mortality than the other 4 rapid scores in treating sepsis patients.
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http://dx.doi.org/10.21037/atm-20-5410DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7475464PMC
August 2020

Routing valley exciton emission of a WS monolayer via delocalized Bloch modes of in-plane inversion-symmetry-broken photonic crystal slabs.

Light Sci Appl 2020 21;9:148. Epub 2020 Aug 21.

State Key Laboratory of Surface Physics, Key Laboratory of Micro- and Nano-Photonics Structures (Ministry of Education) and Department of Physics, Fudan University, 200433 Shanghai, China.

The valleys of two-dimensional transition metal dichalcogenides (TMDCs) offer a new degree of freedom for information processing. To take advantage of this valley degree of freedom, on the one hand, it is feasible to control valleys by utilizing different external stimuli, such as optical and electric fields. On the other hand, nanostructures are also used to separate the valleys by near-field coupling. However, for both of the above methods, either the required low-temperature environment or low degree of coherence properties limit their further applications. Here, we demonstrate that all-dielectric photonic crystal (PhC) slabs without in-plane inversion symmetry (C symmetry) can separate and route valley exciton emission of a WS monolayer at room temperature. Coupling with circularly polarized photonic Bloch modes of such PhC slabs, valley photons emitted by a WS monolayer are routed directionally and are efficiently separated in the far field. In addition, far-field emissions are directionally enhanced and have long-distance spatial coherence properties.
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http://dx.doi.org/10.1038/s41377-020-00387-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7442784PMC
August 2020

IL-10 provides cardioprotection in diabetic myocardial infarction via upregulation of Heme clearance pathways.

JCI Insight 2020 09 3;5(17). Epub 2020 Sep 3.

Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.

Diabetes is a risk factor for myocardial infarction, and outcomes after myocardial infarction are worse among diabetics compared with nondiabetics. Diabetes is associated with impaired Heme clearance. Here, we determined whether heme toxicity and impaired heme clearance contribute to diabetic myocardial infarction injury and assessed IL-10 as a therapeutic agent for diabetic myocardial infarction. Plasma-free hemoglobin was significantly elevated in diabetic mice compared with nondiabetic mice after myocardial infarction. Infarct size had strong correlation to the level of plasma-free hemoglobin. Hemoglobin and reactive iron deposition within the infarct zone were also demonstrated in diabetic MI. IL-10 significantly reduced infarct size and improved cardiac function in diabetic mice. Moreover, IL-10 improved capillary density, reduced apoptosis, and decreased inflammation in the border zone of the infarcted hearts, findings that were partially inhibited by Tin protoporphyrin (a heme oxygenase-1 inhibitor). IL-10 upregulated CD163, the hemoglobin:haptoglobin scavenger receptor, and heme oxygenase-1 in THP-1-derived and primary human CD14+ macrophages. IL-10 significantly protected against ischemic injury when HL-1 cardiomyocytes were cotreated with hemoglobin. Together, our findings indicate that IL-10 is cardioprotective in diabetic myocardial infarction via upregulation of heme clearance pathways. These findings implicate heme clearance as a potentially novel therapeutic direction for diabetic myocardial infarction.
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http://dx.doi.org/10.1172/jci.insight.133050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7526458PMC
September 2020

Biotransformation of phenolic profiles and improvement of antioxidant capacities in jujube juice by select lactic acid bacteria.

Food Chem 2021 Mar 17;339:127859. Epub 2020 Aug 17.

College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China. Electronic address:

The objective of this study was to investigate the effects of four commercial lactic acid bacteria (LAB), namely L. acidophilus, L. casei, L. helveticus and L. plantarum, on the phenolic profiles, antioxidant capacities and flavor profiles of jujube juices prepared from two crop varieties (Ziziphus Jujuba cv. Muzao and Hetian). Results showed that both jujube juices were excellent matrices for LAB growth with more than 11 log CFU/mL of viable counts at the end of fermentation. LAB fermentation dramatically increased total phenolic content, while decreased total flavonoid content of jujube juices. However, antioxidant capacities based on DPPH and FRAP methods were significantly improved by LAB fermentation and positively correlated with caffeic acid and rutin contents. Furthermore, a total of 74 volatile compounds were identified and increased in total content by LAB fermentation, which resulted in 22 and 19 new flavor volatiles formation in Muzao juice and Hetian juice, respectively.
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http://dx.doi.org/10.1016/j.foodchem.2020.127859DOI Listing
March 2021

Complex gene regulation between young and old soybean leaves in responses to manganese toxicity.

Plant Physiol Biochem 2020 Oct 1;155:231-242. Epub 2020 Aug 1.

Root Biology Center, State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, PR China. Electronic address:

Manganese (Mn) is an essential micronutrient for plant growth. However, excess manganese is toxic and inhibits crop production. Although it is widely known that physiological and molecular mechanisms underlie plant responses to Mn toxicity, few studies have been conducted to compare Mn tolerance capabilities between young and old leaves in plants; thus, the mechanisms underlying Mn tolerance in different plant tissues or organs are not fully understood. In this study, the dose responses of soybean to Mn availability were investigated. Genome-wide transcriptomic analysis was subsequently conducted to identify the differentially expressed genes (DEGs) in both young and old leaves of soybean in responses to Mn toxicity. Our results showed that excess Mn severely inhibited soybean growth and increased both Mn accumulation in and brown spots on soybean leaves, especially for the old leaves, strongly suggesting that more Mn was allocated to old leaves in soybean. Transcriptomic profiling revealed that totals of 4410 and 2258 DEGs were separately identified in young leaves and old leaves. Furthermore, only 944 DEGs were found to be commonly regulated in both young and old leaves of soybean, strongly suggesting distinct responses present in soybean young and old leaves in responses to Mn toxicity.
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http://dx.doi.org/10.1016/j.plaphy.2020.07.002DOI Listing
October 2020

Acoustic phonon recycling for photocarrier generation in graphene-WS heterostructures.

Nat Commun 2020 Aug 3;11(1):3876. Epub 2020 Aug 3.

College of Advanced Interdisciplinary Studies, National University of Defense Technology, 410073, Changsha, P.R. China.

Electron-phonon scattering is the key process limiting the efficiency of modern nanoelectronic and optoelectronic devices, in which most of the incident energy is converted to lattice heat and finally dissipates into the environment. Here, we report an acoustic phonon recycling process in graphene-WS heterostructures, which couples the heat generated in graphene back into the carrier distribution in WS. This recycling process is experimentally recorded by spectrally resolved transient absorption microscopy under a wide range of pumping energies from 1.77 to 0.48 eV and is also theoretically described using an interfacial thermal transport model. The acoustic phonon recycling process has a relatively slow characteristic time (>100 ps), which is beneficial for carrier extraction and distinct from the commonly found ultrafast hot carrier transfer (~1 ps) in graphene-WS heterostructures. The combination of phonon recycling and carrier transfer makes graphene-based heterostructures highly attractive for broadband high-efficiency electronic and optoelectronic applications.
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http://dx.doi.org/10.1038/s41467-020-17728-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7400626PMC
August 2020