Publications by authors named "Miao Sun"

322 Publications

Spherical Neutralizing Aptamer Inhibits SARS-CoV-2 Infection and Suppresses Mutational Escape.

J Am Chem Soc 2021 Dec 2. Epub 2021 Dec 2.

The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

New neutralizing agents against SARS-CoV-2 and associated mutant strains are urgently needed for the treatment and prophylaxis of COVID-19. Herein, we develop a spherical cocktail neutralizing aptamer-gold nanoparticle (SNAP) to block the interaction between the receptor-binding domain (RBD) of SARS-CoV-2 and host ACE2. With the multivalent aptamer assembly as well as the steric hindrance effect of the gold scaffold, SNAP exhibits exceptional binding affinity against the RBD with a dissociation constant of 3.90 pM and potent neutralization against authentic SARS-CoV-2 with a half-maximal inhibitory concentration of 142.80 fM, about 2 or 3 orders of magnitude lower than that of the reported neutralizing aptamers and antibodies. More importantly, the synergetic blocking strategy of multivalent multisite binding and steric hindrance ensures broad neutralizing activity of SNAP, almost completely blocking the infection of three mutant pseudoviruses. Overall, the SNAP strategy provides a new direction for the development of antivirus agents against SARS-CoV-2 and other emerging coronaviruses.
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http://dx.doi.org/10.1021/jacs.1c08226DOI Listing
December 2021

Novel melamine-based porous organic polymers: synthesis, characterizations, morphology modifications, and their applications in lithium-sulfur batteries.

Nanotechnology 2021 Dec 2;33(8). Epub 2021 Dec 2.

School of Materials Science and Engineering, Dongguan University of Technology, No. 1 Daxue Road Songshan Lake District, Dongguan 523808, People's Republic of China.

Lithium-sulfur (Li-S) batteries have been considered to be one of the most promising energy storage devices in the next generation. However, the insulating properties of sulfur and the shuttle effect of soluble lithium polysulfides (LiPSs) seriously hinder the practical application of Li-S batteries. In this paper, a novel porous organic polymer (HUT3) was prepared based on the polycondensation between melamine and 1,4-phenylene diisocyanate. The micro morphology of HUT3 was improved bygrowth on different mass fractions of rGO (5%, 10%, 15%), and the obtained HUT3-rGO composites were employed as sulfur carriers in Li-S batteries with promoted the sulfur loading ratio and lithium-ion mobility. Attributed to the synergistic effect of the chemisorption of polar groups and the physical constraints of HUT3 structure, HUT3-rGO/S electrodes exhibits excellent capacity and cyclability performance. For instance, HUT3-10rGO/S electrode exhibits a high initial specific capacity of 950 mAh gat 0.2 C and retains a high capacity of 707 mAh gafter 500 cycles at 1 C. This work emphasizes the importance of the rational design of the chemical structure and opens up a simple way for the development of cathode materials suitable for high-performance Li-S batteries.
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http://dx.doi.org/10.1088/1361-6528/ac39c9DOI Listing
December 2021

Effects of Prenatal Hypoxia on Nervous System Development and Related Diseases.

Front Neurosci 2021 25;15:755554. Epub 2021 Oct 25.

Institute for Fetology, The First Affiliated Hospital of Soochow University, Suzhou, China.

The fetal origins of adult disease (FOAD) hypothesis, which was proposed by David Barker in the United Kingdom in the late 1980s, posited that adult chronic diseases originated from various adverse stimuli in early fetal development. FOAD is associated with a wide range of adult chronic diseases, including cardiovascular disease, cancer, type 2 diabetes and neurological disorders such as schizophrenia, depression, anxiety, and autism. Intrauterine hypoxia/prenatal hypoxia is one of the most common complications of obstetrics and could lead to alterations in brain structure and function; therefore, it is strongly associated with neurological disorders such as cognitive impairment and anxiety. However, how fetal hypoxia results in neurological disorders remains unclear. According to the existing literature, we have summarized the causes of prenatal hypoxia, the effects of prenatal hypoxia on brain development and behavioral phenotypes, and the possible molecular mechanisms.
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http://dx.doi.org/10.3389/fnins.2021.755554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8573102PMC
October 2021

Mechanically excellent nacre-inspired protective steel-concrete composite against hypervelocity impacts.

Sci Rep 2021 Nov 9;11(1):21930. Epub 2021 Nov 9.

Beijing Advanced Innovation Center for Biomedical Engineering, Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University (BUAA), Beijing, 100191, China.

Steel-concrete (SC) composite widely used in military defensive project is due to its impressive mechanical properties, long-lived service, and low cost. However, the growing use of hypervelocity kinetic weapons in the present war puts forward higher requirements for the anti-explosion and penetration performance of military protection engineering. Here, inspired by the special 'brick-and-mortar' (BM) structural feature of natural nacre, we successfully construct a nacre-inspired steel-concrete (NISC) engineering composite with 2510 kg/m, possessing nacre-like lamellar architecture via a bottom-up assembling technique. The NISC engineering composite exhibits nacreous BM structural similarity, high compressive strength of 68.5 MPa, compress modulus of 42.0 GPa, Mohs hardness of 5.5, Young's modulus of 41.5 GPa, and shear modulus of 18.4 GPa, higher than pure concrete. More interestingly, the hypervelocity impact tests reveal the penetration capability of our NISC target material is obviously stronger than that of pure concrete, enhanced up to about 46.8% at the striking velocity of 1 km/s and approximately 30.9% at the striking velocity of 2 km/s, respectively, by examining the damages of targets, the trajectories, penetration depths, and residual projectiles. This mechanically integrated enhancement can be attributed to the nacre-like BM structural architecture derived from assembling the special steel-bar array frame-reinforced concrete platelets. This study highlights a key role of nacre-like structure design in promoting the enhanced hypervelocity impact resistance of steel-concrete composites.
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http://dx.doi.org/10.1038/s41598-021-01308-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8578474PMC
November 2021

Design of an On-Chip Plasmonic Modulator Based on Hybrid Orthogonal Junctions Using Vanadium Dioxide.

Nanomaterials (Basel) 2021 Sep 26;11(10). Epub 2021 Sep 26.

Department of Electrical and Electronic Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Melbourne, VIC 3010, Australia.

We present the design of a plasmonic modulator based on hybrid orthogonal silver junctions using vanadium dioxide as the modulating material on a silicon-on-insulator. The modulator has an ultra-compact footprint of 1.8 μm × 1 μm with a 100 nm × 100 nm modulating section based on the hybrid orthogonal geometry. The modulator takes advantage of the large change in the refractive index of vanadium dioxide during its phase transition to achieve a high modulation depth of 46.89 dB/μm. The simulated device has potential applications in the development of next generation high frequency photonic modulators for optical communications which require nanometer scale footprints, large modulation depth and small insertion losses.
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http://dx.doi.org/10.3390/nano11102507DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8537664PMC
September 2021

A Novel Probiotic Formula, BIOCG, Protects Against Alzheimer's-Related Cognitive Deficits via Regulation of Dendritic Spine Dynamics.

Curr Alzheimer Res 2021 10 21. Epub 2021 Oct 21.

Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu. China.

Background: The brain-gut-microbiome axis has emerged as an important pathway through which perturbations in the gut and/or microbial microenvironment can impact neurological function. Such alterations have been implicated in a variety of neuropsychiatric disorders, includ- ing depression, anxiety, and Alzheimer's Disease (AD) and the use of probiotics as therapy for th- ese diseases remains promising. However, the mechanisms underlying the gut microenvironment's influence on disease pathogenesis and therapy remain unclear.

Objective: The objective of this study is to investigate the effect of a novel probiotic formula, BIOCG, on cognitive function and pathobiological mechanisms, including amyloid processing and dendritic spine dynamics, in a mouse model of AD.

Methods: BIOCG was administered for 3 months to 3xTg or 3xTg; Thy1-YFP AD mice and func- tional outcomes were assessed via behavioral testing and electrophysiology. Mechanisms relevant to AD pathogenesis including dendritic spine morphology and turnover, Amyloid Precursor Pro- tein (APP) processing and microglial phenotype were also evaluated. Finally, we sequenced fecal samples following probiotic treatment to assess the impact on gut microbial composition and corre- late the changes with the above described measures.

Results: Mice treated with BIOCG demonstrated preserved cognitive abilities and stronger Long- Term Potentiation (LTP), spontaneous Excitatory Postsynaptic Currents (sEPSC), and glutamate-in- duced LTPs, indicative of functional and electrophysiological effects. Moreover, we observed atten- uated AD pathogenesis, including reduced Amyloid Beta (Aβ) burden, as well as more mature den- dritic spines in the BIOCG-treated. Our finding of changes in microglial number and phenotype in the treatment group suggests that this formulation may mediate its effects via attenuation of neu- roinflammation. Sequencing data confirmed that the gut microbiome in treated mice was more varied and harbored a greater proportion of "beneficial" bacteria.

Conclusion: Overall, our results indicate that treatment with BIOCG enhances microbial diversity and, through gut-brain axis interactions, attenuates neuroinflammation to produce histologic and functional improvement in AD pathogenesis.
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http://dx.doi.org/10.2174/1567205018666211022091110DOI Listing
October 2021

[Correlation Analysis among Environmental Antibiotic Resistance Genes Abundance, Antibiotics Concentrations, and Heavy Metals Concentrations Based on Web of Science Searches].

Huan Jing Ke Xue 2021 Oct;42(10):4925-4932

State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.

Antibiotics and heavy metals are both important environmental pollutants and selective stressors for antibiotic resistance. However, the impact of their environmental concentrations on antibiotic resistance levels is still unclear. In this paper, research published before 2019 reporting the abundance of antibiotic resistance genes(ARGs), antibiotics concentrations, or heavy metal concentrations were extracted from the Web of Science database, and then statistical regression was used to investigate their correlative association. The results show that antibiotic selection pressure has a statistically significant effect on the increase in the abundance of ARGs in environmental media such as surface water, sediment, and soil, even at very low antibiotic concentrations(<0.05). Different classes of antibiotics show different potential to select and enrich ARGs. Heavy metals and the interaction between antibiotics and heavy metals also have significant effects on ARG transmission(<0.05). Multivariate statistical regression models can better explain the variance of ARG abundance, with values for the water phase and solid phase environmental samples of 0.482 and 0.707 respectively, which are much higher than those achieved using univariate regression models. However, additional environmental factors not included may also affect ARG abundance. The results of this work provide a basis for the evaluation and control of environmental antibiotic resistance.
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http://dx.doi.org/10.13227/j.hjkx.202101043DOI Listing
October 2021

Prenatal hypoxia induced ETR activation and abnormal ROS signalling in pulmonary artery cells of rat offspring.

Reprod Toxicol 2021 Oct 31;105:91-100. Epub 2021 Aug 31.

Institute for Fetology, First Hospital of Soochow University, Suzhou, China; Wuxi Maternal & Child Health Hospital, Jiangsu, China. Electronic address:

Pulmonary arterial hypertension is a progressive disorder characterized by remodeling and increased small pulmonary arteries resistance. Endothelin-1 (ET-1) was related to PAH and ET-1 receptors were up-regulated selectively in the lung when exposed to toxic factor hypoxia. However, the role of ET-1 signaling in the pathogenesis of prenatal hypoxia-induced pulmonary abnormalities remains to be elucidated. Pregnant rats were divided into prenatal hypoxia (10.5 % O from gestational day 4-21) and control group. Their three-month-old offspring male rats were tested for vascular functions and molecular analysis, DNA methylation was assessed for cellular hypoxia. Functional testing showed that ET-1-mediated vasoconstriction was enhanced, and the expressions of endothelin A receptor/B receptor (ETR/ETR), inositol 1,4,5-trisphosphate receptor, type 1, and the sensitivity of calcium channels were increased in the small pulmonary arteries following prenatal hypoxia. q-PCR and DHE staining showed that the expressions of NADPH oxidase 1/4 (Nox1/4) were up-regulated, along with the increased production of superoxide anion. Furthermore, superoxide anion promoted ET-1-mediated pulmonary artery contraction. In the pulmonary artery smooth muscle cell experiments, q-PCR, Western Blot, CCK8 and DHE staining showed that the expressions of ETR, Nox1/4, and superoxide anion were increased by hypoxia, along with promoted cell proliferation. 2,2,6,6-Tetramethyl-1-piperidinyloxy reversed hypoxia-induced cell proliferation. ETR antagonist BQ788 inhibited hypoxia-increased expressions of Nox1/4, superoxide anion production, and proliferation of cells. Moreover, methylation analysis indicated that hypoxia decreased the methylation levels of the ETR promoter in the pulmonary artery smooth muscle cells. The results indicated that prenatal toxic factor hypoxia resulted in abnormal ETR activation, which enhanced ET-1-mediated vasoconstriction of pulmonary arteries and pulmonary artery smooth muscle cell proliferation through ETR/Nox1/4-derived ROS pathway.
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http://dx.doi.org/10.1016/j.reprotox.2021.08.009DOI Listing
October 2021

Electroacupuncture reactivates estrogen receptors to restore the neuroprotective effect of estrogen against cerebral ischemic stroke in long-term ovariectomized rats.

Brain Behav 2021 Oct 2;11(10):e2316. Epub 2021 Sep 2.

Department of Anesthesiology, The Seventh Medical Center of Chinese PLA General Hospital, Beijing, China.

Background: Stroke is a sexually dimorphic disease and a leading cause of death and disability. Estrogen replacement therapy (ERT) confers beneficial neuroprotective effects if administered within a widely accepted time window called the "critical period." However, very few studies have explored the idea of modulating the critical period to enable long-term post-menopausal women to regain more benefits from estrogen therapy. Here, motivated by previous findings that electroacupuncture could both alter estrogen metabolism and induce significant tolerance against stroke, it was explored whether EA could restore estrogen's neuroprotection against cerebral ischemia in long-term ovariectomized (OVX) rats.

Methods: We implemented 1 week(w)-EA pretreatment on OVX-10w or OVX-20w rats, and tested the expression of estrogen receptors, and detected the ERT's neuroprotection against stroke induced by middle cerebral artery occlusion (MCAO).

Results: We found that the expression levels of phospho-ERα-S118 and estrogen receptor β (ERβ) in the striatum of OVX-10w rats were significantly decreased and ERT's neuroprotection was abolished in the OVX-10w rats. However, EA-1w pretreatment could significantly recover the expression levels of phospho-ERα-S118 and ERβ, and also restored the neuroprotective effects of ERT in OVX-10w rats. However, EA-1w pretreatment could not restore the expression of estrogen receptors and ERT's neuroprotection in OVX-20w rats.

Conclusion: Taken together, our study indicates that EA may be an easy intervention that can restore the efficacy of estrogen therapy during the "critical period," which has the potential to improve the stroke outcomes of an enormous number of long-term post-menopausal women. However, the time-sensitive influences for how EA and estrogen metabolism interact with each other should be considered.
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http://dx.doi.org/10.1002/brb3.2316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8553307PMC
October 2021

Undetectable NK Cells due to the FCGR3A Variant, L66H, Which May Not Be Directly Disease-Causing.

J Clin Immunol 2021 11 26;41(8):1957-1959. Epub 2021 Aug 26.

Division of Clinical Immunology and Allergy, Department of Pediatrics, Children's Hospital Los Angeles/Keck School of Medicine of USC, 4650 Sunset Blvd, MS #75, Los Angeles, CA, 90027, USA.

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http://dx.doi.org/10.1007/s10875-021-01122-3DOI Listing
November 2021

Comparative transcriptome analysis provides insight into nitric oxide suppressing lignin accumulation of postharvest okra (Abelmoschus esculentus L.) during cold storage.

Plant Physiol Biochem 2021 Oct 27;167:49-67. Epub 2021 Jul 27.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China. Electronic address:

In plants, NO has been proved the function of improving abiotic stress resistance. However, the role of NO in the lignin metabolism of okra under cold stress has not been clarified. Here, histochemical staining and lignin content analysis showed that cold stress promoted the lignin accumulation of cold stored okra pods, and NO inhibited the lignin accumulation and delayed lignification process. To better understand the roles of NO in okra cold stress resistance mechanism, the full-length transcriptome data of 'Hokkaido' was analyzed. The SNP-treated okra transcriptome and cPTIO-treated okra transcriptome were obtained. A total of 41957 unigenes were screened out from three groups at 10 d, among which, 33, 78 and 18 DEGs were found in ddHO-treat, SNP-treat and cPTIO-treat group, respectively. Transcriptomic data suggested that the genes involved in lignin biosynthesis showed downregulation under SNP treatment. Transcriptomic data and enzyme activity showed that exogenous NO significantly promoted the biosynthesis of endogenous NO by enhancing NOS activity. Transcriptomic data and plant hormone data showed that NO played an important role in the process of inhibiting the ethylene and ABA synthesis mechanism of okra and thereby reducing the endogenous ethylene and ABA content under chilling stress. Relevant physiological data showed that NO helped to the protection of ROS scavenging system and removed the MDA and HO induced by cold stress. These results provided a reference for studying the molecular mechanism of nitric oxide delaying the lignification of okra, and also provided a theoretical basis for postharvest storage of vegetables.
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http://dx.doi.org/10.1016/j.plaphy.2021.07.029DOI Listing
October 2021

Stress modulates Ahi1-dependent nuclear localization of ten-eleven translocation protein 2.

Hum Mol Genet 2021 Nov;30(22):2149-2160

Department of Neurology, The First Affiliated Hospital of Soochow University, Suzhou City 215006, China.

Major depression disorder is one of the most common psychiatric diseases. Recent evidence supports that environmental stress affects gene expression and promotes the pathological process of depression through epigenetic mechanisms. Three ten-eleven translocation (Tet) enzymes are epigenetic regulators of gene expression that promote 5-hydroxymethylcytosine (5hmC) modification of genes. Here, we show that the loss of Tet2 can induce depression-like phenotypes in mice. Paradoxically, using the paradigms of chronic stress, such as chronic mild stress and chronic social defeat stress, we found that depressive behaviors were associated with increased Tet2 expression but decreased global 5hmC level in hippocampus. We examined the genome-wide 5hmC profile in the hippocampus of Tet2 knockout mice and identified 651 dynamically hydroxymethylated regions, some of which overlapped with known depression-associated loci. We further showed that chronic stress could induce the abnormal nuclear translocation of Tet2 protein from cytosol. Through Tet2 immunoprecipitation and mass spectrum analyses, we identified a cellular trafficking protein, Abelson helper integration site-1 (Ahi1), which could interact with Tet2 protein. Ahi1 knockout or knockdown caused the accumulation of Tet2 in cytosol. The reduction of Ahi1 protein under chronic stress explained the abnormal Ahi1-dependent nuclear translocation of Tet2. These findings together provide the evidence for a critical role of modulating Tet2 nuclear translocation in regulating stress response.
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http://dx.doi.org/10.1093/hmg/ddab179DOI Listing
November 2021

Cardiac tissue conductivity estimation using confirmatory factor analysis.

Comput Biol Med 2021 08 24;135:104604. Epub 2021 Jun 24.

Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, the Netherlands.

Impaired electrical conduction has been shown to play an important role in the development of heart rhythm disorders. Being able to determine the conductivity is important to localize the arrhythmogenic substrate that causes abnormalities in atrial tissue. In this work, we present an algorithm to estimate the conductivity from epicardial electrograms (EGMs) using a high-resolution electrode array. With these arrays, it is possible to measure the propagation of the extracellular potential of the cardiac tissue at multiple positions simultaneously. Given this data, it is in principle possible to estimate the tissue conductivity. However, this is an ill-posed problem due to the large number of unknown parameters in the electrophysiological data model. In this paper, we make use of an effective method called confirmatory factor analysis (CFA), which we apply to the cross correlation matrix of the data to estimate the tissue conductivity. CFA comes with identifiability conditions that need to be satisfied to solve the problem, which is, in this case, estimation of the tissue conductivity. These identifiability conditions can be used to find the relationship between the desired resolution and the required amount of data. Numerical experiments on the simulated data demonstrate that the proposed method can localize the conduction blocks in the tissue and can also estimate the smoother variation in the conductivities. The conductivity values estimated from the clinical data are in line with the values reported in literature and the EGMs reconstructed based on the estimated parameters match well with the clinical EGMs.
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http://dx.doi.org/10.1016/j.compbiomed.2021.104604DOI Listing
August 2021

Germplasm resources and genetic breeding of Paeonia: a systematic review.

Hortic Res 2020 Jul 1;7(1):107. Epub 2020 Jul 1.

Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, 100093, Beijing, China.

Members of the genus Paeonia, which consists of globally renowned ornamentals and traditional medicinal plants with a rich history spanning over 1500 years, are widely distributed throughout the Northern Hemisphere. Since 1900, over 2200 new horticultural Paeonia cultivars have been created by the discovery and breeding of wild species. However, information pertaining to Paeonia breeding is considerably fragmented, with fundamental gaps in knowledge, creating a bottleneck in effective breeding strategies. This review systematically introduces Paeonia germplasm resources, including wild species and cultivars, summarizes the breeding strategy and results of each Paeonia cultivar group, and focuses on recent progress in the isolation and functional characterization of structural and regulatory genes related to important horticultural traits. Perspectives pertaining to the resource protection and utilization, breeding and industrialization of Paeonia in the future are also briefly discussed.
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http://dx.doi.org/10.1038/s41438-020-0332-2DOI Listing
July 2020

Polymerized vorinostat mediated photodynamic therapy using lysosomal spatiotemporal synchronized drug release complex.

Colloids Surf B Biointerfaces 2021 Sep 9;205:111903. Epub 2021 Jun 9.

School of Pharmacy, Second Military Medical University, Shanghai, People's Republic of China. Electronic address:

A combination of photodynamic therapy (PDT) and histone deacetylase inhibitor (HDACis) could potentiate single-mode anti-tumor activity of HDACis or PDT to inhibit tumor relapse and metastasis. However, poor solubility and heterogeneity in cellular uptake and tissue distribution hamper the dual mode antitumor effect. For a controlled drug release of photosensitizers and HDACis in cytoplasm, photosensitizer pyropheophorbide-a (Pyro) encapsulated in polymer polyethylene glycol-b-poly (asparaginyl-vorinostat) (simplified as [email protected]) are fabricated to achieve their lysosomal spatiotemporal synchronized release. With HDACis modeling PDT in vitro and in vivo, it seems that polymerized Vorinostat encapsulated photosensitizers significantly inhibited the tumor proliferation and metastasis by spatiotemporal synchronized drugs release, and [email protected] reported here reveals a promising prospect to exert drugs' synergistic effect in a spatiotemporal synchronized manner and can be an effective strategy to inhibit tumor growth, recurrence and metastasis in clinic.
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http://dx.doi.org/10.1016/j.colsurfb.2021.111903DOI Listing
September 2021

Biogeographical patterns and speciation of the genus Pinguicula (Lentibulariaceae) inferred by phylogenetic analyses.

PLoS One 2021 7;16(6):e0252581. Epub 2021 Jun 7.

Florida Museum of Natural History, University of Florida, Gainesville, Florida, United States of America.

Earlier phylogenetic studies in the genus Pinguicua (Lentibulariaceae) suggested that the species within a geographical region was rather monophyletic, although the sampling was limited or was restricted to specific regions. Those results conflicted with the floral morphology-based classification, which has been widely accepted to date. In the current study, one nuclear ribosomal DNA (internal transcribed spacer; ITS) and two regions of chloroplast DNA (matK and rpl32-trnL), from up to ca. 80% of the taxa in the genus Pinguicula, covering all three subgenera, were sequenced to demonstrate the inconsistency and explore a possible evolutionary history of the genus. Some incongruence was observed between nuclear and chloroplast topologies and the results from each of the three DNA analyses conflicted with the morphology-based subgeneric divisions. Both the ITS tree and network, however, corresponded with the biogeographical patterns of the genus supported by life-forms (winter rosette or hibernaculum formation) and basic chromosome numbers (haploidy). The dormant strategy evolved in a specific geographical region is a phylogenetic constraint and a synapomorphic characteristic within a lineage. Therefore, the results denied the idea that the Mexican group, morphologically divided into the three subgenera, independently acquired winter rosette formations. Topological incongruence among the trees or reticulations, indicated by parallel edges in phylogenetic networks, implied that some taxa originated by introgressive hybridisation. Although there are exceptions, species within the same geographical region arose from a common ancestor. Therefore, the classification by the floral characteristics is rather unreliable. The results obtained from this study suggest that evolution within the genus Pinguicula has involved; 1) ancient expansions to geographical regions with gene flow and subsequent vicariance with genetic drift, 2) acquirement of a common dormant strategy within a specific lineage to adapt a local climate (i.e., synapomorphic characteristic), 3) recent speciation in a short time span linked to introgressive hybridisation or multiplying the ploidy level (i.e., divergence), and 4) parallel evolution in floral traits among lineages found in different geographical regions (i.e., convergence). As such, the floral morphology masks and obscures the phylogenetic relationships among species in the genus.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0252581PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184156PMC
November 2021

Antenatal Hypoxia Affects Pulmonary Artery Contractile Functions via Downregulating L-type Ca Channels Subunit Alpha1 C in Adult Male Offspring.

J Am Heart Assoc 2021 04 10;10(8):e019922. Epub 2021 Apr 10.

From the Institute for Fetology First Hospital of Soochow University Suzhou China.

Background Antenatal intrauterine fetal hypoxia is a common pregnancy complication that has profound adverse effects on an individual's vascular health later in life. Pulmonary arteries are sensitive to hypoxia, but adverse effects of antenatal hypoxia on pulmonary vasoreactivities in the offspring remain unknown. This study aimed to determine the effects and related mechanisms of antenatal hypoxia on pulmonary artery functions in adult male offspring. Methods and Results Pregnant Sprague-Dawley rats were housed in a normoxic or hypoxic (10.5% O) chamber from gestation days 10 to 20. Male offspring were euthanized at 16 weeks old (adult offspring). Pulmonary arteries were collected for vascular function, electrophysiology, target gene expression, and promoter methylation studies. In pulmonary artery rings, contractions to serotonin hydrochloride, angiotensin II, or phenylephrine were reduced in the antenatal hypoxic offspring, which resulted from inactivated L-type Ca channels. In pulmonary artery smooth muscle cells, the basal whole-cell Ca currents, as well as vasoconstrictor-induced Ca transients were significantly reduced in antenatal hypoxic offspring. In addition, increased promoter methylations within L-type Ca channel subunit alpha1 C were compatible with its reduced expressions. Conclusions This study indicated that antenatal hypoxia programmed long-lasting vascular hypocontractility in the male offspring that is linked to decreases of L-type Ca channel subunit alpha1 C in the pulmonary arteries. Antenatal hypoxia resulted in pulmonary artery adverse outcomes in postnatal offspring, was strongly associated with reprogrammed L-type Ca channel subunit alpha1 C expression via a DNA methylation-mediated epigenetic mechanism, advancing understanding toward the effect of antenatal hypoxia in early life on long-term vascular health.
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http://dx.doi.org/10.1161/JAHA.120.019922DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8174167PMC
April 2021

Ahi1 regulates the nuclear translocation of glucocorticoid receptor to modulate stress response.

Transl Psychiatry 2021 03 29;11(1):188. Epub 2021 Mar 29.

Guangdong Key Laboratory of non-human primate models, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, 510632, Guangzhou, China.

Stress activates the nuclear translocation of glucocorticoid receptors (GR) to trigger gene expression. Abnormal GR levels can alter the stress responses in animals and therapeutic effects of antidepressants. Here, we reported that stress-mediated nuclear translocation of GR reduced Ahi1 in the stressed cells and mouse brains. Ahi1 interacts with GR to stabilize each other in the cytoplasm. Importantly, Ahi1 deficiency promotes the degradation of GR in the cytoplasm and reduced the nuclear translocation of GR in response to stress. Genetic depletion of Ahi1 in mice caused hyposensitivity to antidepressants under the stress condition. These findings suggest that AHI1 is an important regulator of GR level and may serve as a therapeutic target for stress-related disorders.
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http://dx.doi.org/10.1038/s41398-021-01305-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8007735PMC
March 2021

The transcription factor Bcl11b promotes both canonical and adaptive NK cell differentiation.

Sci Immunol 2021 Mar;6(57)

Broegelmann Research Laboratory, Department of Clinical Sciences, University of Bergen, N-5021 Bergen, Norway.

Epigenetic landscapes can provide insight into regulation of gene expression and cellular diversity. Here, we examined the transcriptional and epigenetic profiles of seven human blood natural killer (NK) cell populations, including adaptive NK cells. The gene, encoding a transcription factor (TF) essential for T cell development and function, was the most extensively regulated, with expression increasing throughout NK cell differentiation. Several Bcl11b-regulated genes associated with T cell signaling were specifically expressed in adaptive NK cell subsets. Regulatory networks revealed reciprocal regulation at distinct stages of NK cell differentiation, with Bcl11b repressing and in canonical and adaptive NK cells, respectively. A critical role for Bcl11b in driving NK cell differentiation was corroborated in -mutated patients and by ectopic Bcl11b expression. Moreover, was required for adaptive NK cell responses in a murine cytomegalovirus model, supporting expansion of these cells. Together, we define the TF regulatory circuitry of human NK cells and uncover a critical role for Bcl11b in promoting NK cell differentiation and function.
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http://dx.doi.org/10.1126/sciimmunol.abc9801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8274449PMC
March 2021

Remote Limb Ischemic Postconditioning Protects against Ischemic Stroke via Modulating Microglia/Macrophage Polarization in Mice.

J Immunol Res 2021 19;2021:6688053. Epub 2021 Feb 19.

Department of Neurology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang 110004, China.

Aim: The protection against ischemia/reperfusion injury mediated by remote limb ischemic postconditioning (RIPC) shows great clinical value in ischemic stroke therapy, but the particular mechanism of RIPC remains unclear.

Methods: We carried out middle cerebral artery occlusion/reperfusion (MCAO/R) surgery on C57BL/6 male mice. RIPC was generated by 10-minute occlusion followed by the same period of reperfusion of the bilateral hind limb femoral artery and repeated for 3 cycles. Infarct size and neurological score were performed to assess stroke outcomes. Ly6C monocytes were quantified in the blood and brain by flow cytometry. Real-time PCR, ELISA, and immunofluorescence were utilized to detect phenotype of proinflammatory M1 and anti-inflammatory M2 microglia/macrophage. Nuclear factor B (NF-B) and peroxisome proliferator-activated receptor (PPAR) levels were detected using Western blot.

Results: At 24 and 72 h after MCAO, RIPC drastically attenuated infarct size and ameliorated the neurological deficits of mice and facilitated transmigration of Ly6C monocytes to the brain postischemia reperfusion. Furthermore, RIPC contributed to increased M2 and reduced M1 microglia/macrophage through inhibiting NF-B and promoting PPAR activation.

Conclusion: Our results reveal pharmacological effect of RIPC in promoting microglia/macrophage transferring from M1 to M2 phenotype after MCAO/R in mice, which provides theoretical support for the therapeutic effect of RIPC in ischemic stroke.
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http://dx.doi.org/10.1155/2021/6688053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7910075PMC
November 2021

Carbonyl cyanide 3-chlorophenylhydrazone induced the imbalance of mitochondrial homeostasis in the liver of Megalobrama amblycephala: A dynamic study.

Comp Biochem Physiol C Toxicol Pharmacol 2021 Jun 19;244:109003. Epub 2021 Feb 19.

Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, No. 1 Weigang Road, Nanjing 210095, People's Republic of China. Electronic address:

Carbonylcyanide-3-chlorophenylhydrazone (CCCP) is a protonophore, which causes uncoupling of proton gradient in the inner mitochondrial membrane, thus inhibiting the rate of ATP synthesis. However, this information is manly derived from mammals, while its effects on the mitochondrial homeostasis of aquatic animals are largely unknown. In this study, the mitochondrial homeostasis of a carp fish Megalobrama amblycephala was investigated systematically in a time-course manner by using CCCP. Fish was injected intraperitoneally with CCCP (1.8 mg/kg per body weight) and DMSO (control), respectively. The results showed that CCCP treatment induced hepatic mitochondrial oxidative stress, as was evidenced by the significantly increased MDA and PC contents coupled with the decreased SOD and MnSOD activities. Meanwhile, mitochondrial fission was up-regulated remarkably characterized by the increased transcriptions of Drp-1, Fis-1 and Mff. However, the opposite was true for mitochondrial fusion, as was indicative of the decreased transcriptions of Mfn-1, Mfn-2 and Opa-1. This consequently triggered mitophagy, as was supported by the accumulated mitochondrial autophagosomes and the increased protein levels of PINK1, Parkin, LC3-II and P62 accompanied by the increased LC3-II/LC3-I ratio. Mitochondrial biogenesis and function both decreased significantly addressed by the decreased activities of CS, SDH and complex I, IV and V, as well as the protein levels of PGC-1β coupled with the decreased transcriptions of TFAM, COX-1, COX-2 and ATP-6. Unlikely, DMSO treatment exerted little influence. Overall, CCCP treatment resulted in the imbalance of mitochondrial homeostasis in Megalobrama amblycephala by promoting mitochondrial oxidative stress, fission and mitophagy, but depressing mitochondrial fusion, biogenesis and function.
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http://dx.doi.org/10.1016/j.cbpc.2021.109003DOI Listing
June 2021

Aptamer Blocking Strategy Inhibits SARS-CoV-2 Virus Infection.

Angew Chem Int Ed Engl 2021 04 10;60(18):10266-10272. Epub 2021 Mar 10.

The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, the Key Laboratory of Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, China.

The COVID-19 pandemic caused by SARS-CoV-2 is threating global health. Inhibiting interaction of the receptor-binding domain of SARS-CoV-2 S protein (S ) and human ACE2 receptor is a promising treatment strategy. However, SARS-CoV-2 neutralizing antibodies are compromised by their risk of antibody-dependent enhancement (ADE) and unfavorably large size for intranasal delivery. To avoid these limitations, we demonstrated an aptamer blocking strategy by engineering aptamers' binding to the region on S that directly mediates ACE2 receptor engagement, leading to block SARS-CoV-2 infection. With aptamer selection against S and molecular docking, aptamer CoV2-6 was identified and applied to prevent, compete with, and substitute ACE2 from binding to S . CoV2-6 was further shortened and engineered as a circular bivalent aptamer CoV2-6C3 (cb-CoV2-6C3) to improve the stability, affinity, and inhibition efficacy. cb-CoV2-6C3 is stable in serum for more than 12 h and can be stored at room temperature for more than 14 days. Furthermore, cb-CoV2-6C3 binds to S with high affinity (K =0.13 nM) and blocks authentic SARS-CoV-2 virus with an IC of 0.42 nM.
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http://dx.doi.org/10.1002/anie.202100225DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8014204PMC
April 2021

Epigenetic Mechanisms of Paternal Stress in Offspring Development and Diseases.

Int J Genomics 2021 19;2021:6632719. Epub 2021 Jan 19.

Institute of Neuroscience, Soochow University, Suzhou City, China.

The major biological function of the sperm cell is to transmit the paternal genetic and epigenetic information to the embryo as well as the following offspring. Sperm has a unique epigenome. An increasing body of epidemiological study supports that paternal stress induced by environmental exposures and lifestyle can modulate the sperm epigenome (including histone modification, DNA methylation, and noncoding RNA expression), sperm-egg fusion, embryo development, and offspring health. Based on the existing literature, we have summarized the paternal exposure on sperm epigenome along with the representative phenotypes of offspring and the possible mechanism involved.
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http://dx.doi.org/10.1155/2021/6632719DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7837765PMC
January 2021

Characterization of Pathogenicity-Associated V2 Protein of Tobacco Curly Shoot Virus.

Int J Mol Sci 2021 Jan 18;22(2). Epub 2021 Jan 18.

Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China.

V2 proteins encoded by some whitefly-transmitted geminiviruses were reported to be functionally important proteins. However, the functions of the V2 protein of tobacco curly shoot virus (TbCSV), a monopartite begomovirus that causes leaf curl disease on tomato and tobacco in China, remains to be characterized. In our report, an infiltration-mediated transient expression assay indicated that TbCSV V2 can suppress local and systemic RNA silencing and the deletion analyses demonstrated that the amino acid region 1-92 of V2, including the five predicted α-helices, are required for local RNA silencing suppression. Site-directed substitutions showed that the conserved basic and ring-structured amino acids in TbCSV V2 are critical for its suppressor activity. Potato virus X-mediated heteroexpression of TbCSV V2 in induced hypersensitive response-like (HR-like) cell death and systemic necrosis in a manner independent of V2's suppressor activity. Furthermore, TbCSV infectious clone mutant with untranslated V2 protein (TbCSV) could not induce visual symptoms, and coinfection with betasatellite (TbCSB) could obviously elevate the viral accumulation and symptom development. Interestingly, symptom recovery occurred at 15 days postinoculation (dpi) and onward in TbCSV/TbCSB-inoculated plants. The presented work contributes to understanding the RNA silencing suppression activity of TbCSV V2 and extends our knowledge of the multifunctional role of begomovirus-encoded V2 proteins during viral infections.
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http://dx.doi.org/10.3390/ijms22020923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831499PMC
January 2021

Cottonseed Oil Alleviates Ischemic Stroke-Induced Oxidative Stress Injury Via Activating the Nrf2 Signaling Pathway.

Mol Neurobiol 2021 Jun 14;58(6):2494-2507. Epub 2021 Jan 14.

Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing, 100853, China.

Oxidative stress is believed to be one of the primary causes in ischemic stroke injury, and the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway is the most important endogenous antioxidative stress damage pathway. Cottonseed oil (CSO), which is used mostly as a solvent for lipid-soluble drugs, has been shown to exert antioxidative effects against peripheral tissue injury. However, the effects and mechanisms of CSO on ischemic stroke-induced oxidative stress injury and the Nrf2 signaling pathway remain largely unknown. In this study, we investigated the potential of CSO in regulating oxidative stress injury induced by middle cerebral artery occlusion and reperfusion (MCAO-R), or oxygen and glucose deprivation and reperfusion (OGD-R). We found that 1.3 mL/kg CSO treatment of male rats with a subcutaneous injection once every other day for 3 weeks significantly improved neurological deficit; reduced infarction volume; alleviated neuronal injuries; reduced the content of ROS and MDA; increased the activity of SOD, GSH, and GSH-PX; and markedly increased the expression of Nrf2. Furthermore, treatment with 10 μL/mL CSO to a neuron cell line (HT-22) for 24 h significantly increased cell viability and decreased cell apoptosis after OGD-R injury; significantly reduced the levels of ROS and MDA; increased the activity of SOD, GSH, and GSH-PX; and induced an increase in Nrf2 nuclear translocation. Based on our findings, we conclude that CSO treatment alleviates ischemic stroke injury-induced oxidative stress via activating the Nrf2 signaling pathway, highlighting the potential that CSO has as a therapeutic for ischemic strokes.
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http://dx.doi.org/10.1007/s12035-020-02256-yDOI Listing
June 2021

Identification of a novel mutation in the KITLG gene in a Chinese family with familial progressive hyper- and hypopigmentation.

BMC Med Genomics 2021 01 6;14(1):12. Epub 2021 Jan 6.

Department of Dermatology, The First Affiliated Hospital of Soochow University, Suzhou City, Jiangsu, China.

Background: Familial progressive hyper- and hypopigmentation (FPHH, MIM 145250) is a rare hereditary skin disorder that is predominantly characterized by progressive, diffuse, partly blotchy hyperpigmented lesions intermingled with scattered hypopigmented spots, lentigines and sometimes Cafe-au-lait spots (CALs). Heterozygous mutations of the KIT ligand (KITLG, MIM 184745) gene are responsible for FPHH. To date, only eight KITLG mutations have been reported to be associated with FPHH, and no clear genotype-phenotype correlations have been established. This study aimed to identify the causative mutations in the KITLG gene in two Chinese FPHH patients.

Methods: Direct sequencing of the coding regions of KITLG was performed. Pathogenicity prediction was performed using bioinformatics tools, including SIFT, Polyphen2, and SWISS-MODEL, and the results were further evaluated according to the 2015 American College of Medical Genetics and Genomics (ACMG) guidelines.

Results: The novel mutation c.104A > T (p.Asn35Ile) and the recurrent mutation c.101C > T (p.Thr34Ile) in KITLG were identified. As shown using SIFT and Polyphen-2 software, both mutations identified in this study were predicted to be detrimental variations. Three-dimensional protein structure modeling indicated that the mutant KITLG proteins might affect the affinity of KITLG for its receptor, c-KIT. According to the 2015 ACMG guidelines, the novel mutation c.104A > T was 'likely pathogenic'.

Conclusions: To date, most of the identified KITLG mutations have been clustered within the conserved VTNNV motif (amino acids 33-37) in exon 2. The known mutations are only involved in 33 V, 34 T, 36 N, and 37 V but not 35 N. We have now identified a novel mutation in KITLG, c.104A > T, that was first reported in FPHH within the conserved 35 N motif. These results strengthen our understanding of FPHH and expand the mutational spectrum of the KITLG gene.
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http://dx.doi.org/10.1186/s12920-020-00851-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7789533PMC
January 2021

Biodegradable intramedullary nail (BIN) with high-strength bioceramics for bone fracture.

J Mater Chem B 2021 01 6;9(4):969-982. Epub 2021 Jan 6.

The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, and Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou, Zhejiang 310006, China.

About 10 million fractures occur worldwide each year, of which more than 60% are long bone fractures. It is generally agreed that intramedullary nails have significant advantages in rigid fracture fixation. Metal intramedullary nails (INs) can provide strong support but a stress shielding effect can occur that results in nonunion healing in clinic. Nondegradable metals also need to be removed by a second operation. Could INs be biodegradable and used to overcome this issue? As current degradable biomaterials always suffer from low strength and cannot be used in Ins, herein, we report a novel device consisting of biodegradable IN (BIN) made for the first time with bioceramics. These BINs have an extremely high bending strength and stable internal and external structure. Experiments show that the BINs could not only fix and support the tibial fracture model, but also promote osteogenesis and affect the microenvironment of the bone marrow cavity. Therefore, they could be expected to replace traditional metal IN and become a more effective treatment option for tibial fractures.
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http://dx.doi.org/10.1039/d0tb02423fDOI Listing
January 2021

Analysis of Chemical Components in the Roots of Eight Intersubgeneric Hybrids of Paeonia.

Chem Biodivers 2021 Feb 3;18(2):e2000848. Epub 2021 Feb 3.

College of Landscape Architecture, Beijing Forestry University, Beijing Key Laboratory of Ornamental Plants Germplasm Innovation and Molecular Breeding, National Engineering Research Center for Floriculture, Beijing, 100083, P. R. China.

Paeonia cultivars are famous ornamental plants, and some of them are also traditional Chinese medicinal resources. Intersubgeneric hybrids of Paeonia (IHPs) are formed by the hybridization of herbaceous peony (Paeonia lactiflora) and tree peony (Paeonia×suffruticosa or lutea hybrid tree peony). The phenotypic characteristics of IHPs are similar to those of herbaceous peony, and their root systems are large and vigorous. However, their medicinal value has not been reported yet. In this study, the roots of eight IHP samples were analyzed by high performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS). A total of 18 compounds were identified, including phenols, paeonols, monoterpene glycosides, and tannins. The contents of monoterpene glycosides and tannins in IHPs were higher than herbaceous peony and tree peony, exceeding 44.76 mg/g DW and 11.50 mg/g DW, respectively. Three IHPs, 'Prairie Charm', 'Garden Treasure', and 'Yellow Emperor', with more types and a higher content of medicinal compounds, were screened out by cluster analysis. These IHPs have considerable potential for the development of medicinal resources.
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http://dx.doi.org/10.1002/cbdv.202000848DOI Listing
February 2021

Carrier assisted differential detection with a generalized transfer function.

Opt Express 2020 Nov;28(24):35946-35959

Direct detection capable of optical field recovery not only enables high-order modulation for high spectral efficiency (SE) but also extends the transmission reach by digital compensation of linear channel impairments such as chromatic dispersion. Recently, to bridge the gap between direct detection and coherent detection, carrier assisted differential detection (CADD) has been proposed for the reception of complex-valued double-sideband signals. In this paper, we extend the concept CADD to a general selection of the transfer functions, beyond the originally-proposed delay interferometer. To validate the proposed CADD approach, we utilize an optical filter based on silicon photonics microring resonator (MRR) as one realization of the generalized transfer functions. With the MRR based optical filter, both the required carrier-to-signal power ratio (CSPR) and the optical signal-to-noise ratio (OSNR) sensitivity are drastically improved over the conventional CADD due to the significantly suppressed signal-signal beating interference (SSBI). In addition, the proposed CADD is resilient to the wavelength offset up to several GHz between the transmitter laser and the center wavelength of the MRR based optical filter. With the proposed transfer function, CADD provides a novel approach for achieving high-SE transmission with superior receiver sensitivity and could be potentially useful for inter-/intra-datacenter or mobile front haul applications.
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http://dx.doi.org/10.1364/OE.410166DOI Listing
November 2020

Effect of Cover Plate on the Ballistic Performance of Ceramic Armor.

Materials (Basel) 2020 Dec 22;14(1). Epub 2020 Dec 22.

School of Astronautics, Harbin Institute of Technology, Harbin 150080, China.

The interface defeat and dwell can effectively improve the ballistic performance of ceramic armors under high velocity impact of long rod projectiles. Confinement conditions along both axial and radial directions of ceramic armors can affect these behaviors. With the aim of giving an insight into the effect of cover plate thickness and connection mode of cover plates with confining tubes on these behaviors, numerical simulations were performed in which the confined silicon carbide (SiC) targets with cover plates were impacted by tungsten rods. The pressure on the surfaces of SiC targets with fixed cover plates are compared to that with free cover plates, showing that the plates fixed with the confining tubes can produce higher pressure by way of wedging. With the increase in cover plate thickness, the dwell duration of the tungsten rods on the ceramic interface gradually grows. In addition, the upper and lower limits of transition impact velocities for the SiC targets with cover plates in different connection modes (i.e., free or fixed) were obtained and analyzed. The results show that the increase rate of the transition velocity region for the cover plate with the fixed-mode is relatively stable and lower than with the free-mode. On this basis, the fixed cover plate contributes higher ballistic performances to the SiC target than the free cover plate. It is also noteworthy that the size of transition velocity region does not enlarge linearly with the increase in cover plate thickness due to the slow growth of the upper limit. Accordingly, thickness thresholds exist, which are 5 mm and 6 mm for the fixed and free cover plates, respectively. Considering the ballistic performance and economy, the cover plate with the thickness ranging from 3 mm to 5 mm, i.e., 1.5~2.5 times of the tungsten rod diameter, is ideal for the structural dimensions in this paper.
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http://dx.doi.org/10.3390/ma14010001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7792607PMC
December 2020
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