Publications by authors named "Yifei Zhang"

260 Publications

Programmed genome editing by a miniature CRISPR-Cas12f nuclease.

Nat Chem Biol 2021 Sep 2. Epub 2021 Sep 2.

School of Physical Science and Technology, ShanghaiTech University, Shanghai, China.

The RNA-guided CRISPR-associated (Cas) nucleases are versatile tools for genome editing in various organisms. The large sizes of the commonly used Cas9 and Cas12a nucleases restrict their flexibility in therapeutic applications that use the cargo-size-limited adeno-associated virus delivery vehicle. More compact systems would thus offer more therapeutic options and functionality for this field. Here, we report a miniature class 2 type V-F CRISPR-Cas genome-editing system from Acidibacillus sulfuroxidans (AsCas12f1, 422 amino acids). AsCas12f1 is an RNA-guided endonuclease that recognizes 5' T-rich protospacer adjacent motifs and creates staggered double-stranded breaks to target DNA. We show that AsCas12f1 functions as an effective genome-editing tool in both bacteria and human cells using various delivery methods, including plasmid, ribonucleoprotein and adeno-associated virus. The small size of AsCas12f1 offers advantages for cellular delivery, and characterizations of AsCas12f1 may facilitate engineering more compact genome-manipulation technologies.
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http://dx.doi.org/10.1038/s41589-021-00868-6DOI Listing
September 2021

Targeted genetic screening in bacteria with a Cas12k-guided transposase.

Cell Rep 2021 Aug;36(9):109635

School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China; Guangzhou Laboratory, Guangzhou 510120, China. Electronic address:

Microbes employ sophisticated cellular networks encoded by complex genomes to rapidly adapt to changing environments. High-throughput genome engineering methods are valuable tools for functionally profiling genotype-phenotype relationships and understanding the complexity of cellular networks. However, current methods either rely on special homologous recombination systems and are thus applicable in only limited bacterial species or can generate only nonspecific mutations and thus require extensive subsequent screening. Here, we report a site-specific transposon-assisted genome engineering (STAGE) method that allows high-throughput Cas12k-guided mutagenesis in various microorganisms, such as Pseudomonas aeruginosa and Klebsiella pneumoniae. Exploiting the powerful STAGE technique, we construct a site-specific transposon mutant library that focuses on all possible transcription factors (TFs) in P. aeruginosa, enabling the comprehensive identification of essential genes and antibiotic-resistance-related factors. Given its broad host range activity and easy programmability, this method can be widely adapted to diverse microbial species for rapid genome engineering and strain evolution.
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http://dx.doi.org/10.1016/j.celrep.2021.109635DOI Listing
August 2021

MapZ deficiency leads to defects in the envelope structure and changes stress tolerance of Streptococcus mutans.

Mol Oral Microbiol 2021 Aug 31. Epub 2021 Aug 31.

Department of Geriatric Dentistry, Peking University Hospital of Stomatology, Beijing, P. R. China.

Cell division is a central process in bacteria and a prerequisite for pathogenicity. Several proteins are involved in this process to ensure the accurate localization and proper function of the division machinery. In Streptococcus mutans, MapZ marks the division sites and position of the Z-ring to regulate cell division; however, whether MapZ deficiency can impair the cariogenic virulence of S. mutans remains unclear. Here, using a phenotypic assay and RNA-seq, we investigated the role of MapZ in cell envelope maintenance, biofilm formation, and stress tolerance in S. mutans. The results show that MapZ is important for normal cell shape and envelope structure, and its deletion causes abnormal septum structure and a thin cell wall. Subsequently, we found that the absence of MapZ leads to a greater level of cell death within 12 h biofilms, but it does not seem to affect biofilm architecture and accumulation. mapZ deletion also results in a decreased acid and osmotic stress tolerance. Furthermore, RNA-seq data reveal that MapZ deficiency causes changes in the expression levels of genes involved in transport systems, sugar metabolism, nature competence, and bacteriocin synthesis. Interestingly, we found that mapZ mutation renders S. mutans more sensitive to chlorhexidine. Taken together, our study suggests that MapZ plays a role in maintaining cell envelope structure and stress tolerance in S. mutans, showing a potential application as a drug target for caries prevention.
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http://dx.doi.org/10.1111/omi.12352DOI Listing
August 2021

Standardized Procedures Important for Improving Low-Temperature Ceramic Fuel Cell Technology: From Transient to Steady State Assessment.

Nanomaterials (Basel) 2021 Jul 26;11(8). Epub 2021 Jul 26.

Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology, School of Energy & Environment, Southeast University, Nanjing 210096, China.

As the stress-strain curve of standardized metal samples provides the basic details about mechanical properties of structural materials, the polarization curve or current-voltage characteristics of fuel cells are vitally important to explore the scientific mechanism of various solid oxide cells aiming at low operational temperatures (below 600 °C), ranging from protonic conductor ceramic cells (PCFC) to emerging Semiconductor ionic fuel cell (SIFC)/Semiconductor membrane fuel cells (SMFC). Thus far, worldwide efforts to achieve higher nominal peak power density (PPD) at a low operational temperature of over 0.1 s/cm ionic conductivity of electrolyte and super catalyst electrode is the key challenge for SIFCs. Thus, we illustrate an alternative approach to the present PPD concept and current-voltage characteristic. Case studies reveal that the holy grail of 1 W/cm from journal publications is expected to be reconsidered and normalized, since partial cells may still remain in a transient state (TS) to some extent, which means that they are unable to fulfill the prerequisite of a steady state (SS) characteristic of polarization curve measurement. Depending on the testing parameters, the reported PPD value can arbitrarily exist between higher transient power density (TPD) and lower stable power density (SPD). Herein, a standardized procedure has been proposed by modifying a quasi-steady state (QSS) characterization based on stabilized cell and time-prolonged measurements of common - plots. The present study indicates, when compared with steady state value, that QSS power density itself still provides a better approximation for the real performance of fuel cells, and concurrently recalls a novel paradigm transformation from a transient to steady state perspective in the oxide solid fuel cell community.
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http://dx.doi.org/10.3390/nano11081923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8399102PMC
July 2021

sp. nov., isolated from subgingival plaque of periodontitis patient.

Int J Syst Evol Microbiol 2021 Aug;71(8)

Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China.

Two carbon dioxide-requiring, gliding, Gram-stain-negative strains, designated p1a2 and 051621, were isolated from subgingival plaque in association with severe periodontitis. The 16S rRNA gene sequence analysis revealed that they represented members of the genus and had less than 96.4 % pairwise similarity with species with validly published names in this genus. The whole-genome sequences of those strains had less than 91.9 % average nucleotide identity and 48.4 % digital DNA-DNA hybridization values with the other type strains of species of the genus , both below the species delineation threshold. The results of pan-genomic analysis indicated that p1a2 and 051621 shared 765 core gene families with the other ten species in this genus, and the numbers of strain-specific gene families were 493 and 455, respectively. The major fatty acids were iso-C and C. A combination of phenotypic, chemotaxonomic, phylogenetic and genotypic data clearly indicate that p1a2 and 051621 should be considered to represent a novel species of the genus , for which the name sp. nov. is proposed. The type strain is p1a2 (=CGMCC 1.17337=JCM 34126).
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http://dx.doi.org/10.1099/ijsem.0.004979DOI Listing
August 2021

Deciphering CT texture features of human visceral fat to evaluate metabolic disorders and surgery-induced weight loss effects.

EBioMedicine 2021 Jul 3;69:103471. Epub 2021 Jul 3.

Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Electronic address:

Background: Metabolic syndrome (MetS) is highly related to the excessive accumulation of visceral adipose tissue (VAT). Quantitative measurements of VAT are commonly applied in clinical practice for measurement of metabolic risks; however, it remains largely unknown whether the texture of VAT can evaluate visceral adiposity, stratify MetS and predict surgery-induced weight loss effects.

Methods: 675 Chinese adult volunteers and 63 obese patients (with bariatric surgery) were enrolled. Texture features were extracted from VATs of the computed tomography (CT) scans and machine learning was applied to identify significant imaging biomarkers associated with metabolic-related traits.

Findings: Combined with sex, ten VAT texture features achieved areas under the curve (AUCs) of 0.872, 0.888, 0.961, and 0.947 for predicting the prevalence of insulin resistance, MetS, central obesity, and visceral obesity, respectively. A novel imaging biomarker, RunEntropy, was identified to be significantly associated with major metabolic outcomes and a 3.5-year follow-up in 338 volunteers demonstrated its long-term effectiveness. More importantly, the preoperative imaging biomarkers yielded high AUCs and accuracies for estimation of surgery responses, including the percentage of excess weight loss (%EWL) (0.867 and 74.6%), postoperative BMI group (0.930 and 76.1%), postoperative insulin resistance (0.947 and 88.9%), and excess visceral fat loss (the proportion of visceral fat reduced over 50%; 0.928 and 84.1%).

Interpretation: This study shows that the texture features of VAT have significant clinical implications in evaluating metabolic disorders and predicting surgery-induced weight loss effects.

Funding: The complete list of funders can be found in the Acknowledgement section.
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http://dx.doi.org/10.1016/j.ebiom.2021.103471DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8264112PMC
July 2021

Association of night-time sleep and day napping with the prevalence of MOSH in young obese men.

Andrology 2021 Jul 1. Epub 2021 Jul 1.

Department of Endocrine and Metabolic Diseases, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China.

Background: Obesity in men is also shown to be associated with reduced reproductive potential, and this particular subtype was described as male obesity-associated secondary hypogonadism (MOSH). Recent studies showing the influence of sleep disorders on testosterone levels suggested a potential role of sleep disorders in determining the development of MOSH.

Objectives: To assess the association between night-time sleep duration and day napping and the prevalence of MOSH.

Materials And Methods: In this cross-sectional study, 226 obese male participants aged 18-30 years were enrolled. Daytime napping and night-time sleep duration data were collected using a standardized self-reported Chinese-language questionnaire. MOSH was defined as obese men (BMI ≥ 30 kg/m ) with hypogonadal symptoms and decreased total testosterone level and/or free testosterone level, excluding other causes of hypogonadism.

Results: The overall prevalence of MOSH was 48.2% in this study. An inverse association was observed between night sleep duration and the risk of prevalent MOSH. Men who reported fewer than 6 h of night-time sleep had reduced total testosterone and free testosterone levels and an increased risk of MOSH. Further regression analysis revealed that after adjustment for potential confounders, the odds ratio of MOSH for the short night-time sleep group (<6 h vs. 6-8 h) was 6.17 (p = 0.040). No significant association was observed between day napping status and prevalence of MOSH.

Discussion And Conclusion: Short night sleep duration was associated with an increased risk of MOSH in the young obese Chinese population. Chronic sleep curtailment has a negative effect on obese men's health in terms of hypogonadism.
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http://dx.doi.org/10.1111/andr.13074DOI Listing
July 2021

Applying the Noninferiority Paradigm to Assess Exposure-Response Similarity and Dose Between Pediatric and Adult Patients.

J Clin Pharmacol 2021 06;61 Suppl 1:S165-S174

Office of New Drugs, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA.

The use of extrapolation of efficacy in pediatric drug development programs is possible when disease progression and treatment response are similar in adult and pediatric populations. Historically, the exposure-response (E-R) similarity was assessed by visual inspection of 2 E-R curves to support pediatric extrapolation. The aim of this study was to develop a quantitative framework to describe the E-R relationship and the difference in E-R between pediatric and adult patients based on accumulated experience in pediatric drug development programs. Using clinical data for 8 drugs with either a linear or nonlinear E-R relationship, we adapted the methodology used in noninferiority testing to assess the E-R similarity between adult and pediatric patients at the targeted drug exposure. We implemented bootstrap-based and Bayesian-based methodologies to estimate the probability of concluding noninferiority of the E-R relationship. This approach provides objective criteria that can be applied to an assessment of E-R noninferiority in 2 populations to support extrapolation of efficacy in drug development programs from adults to pediatric populations.
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http://dx.doi.org/10.1002/jcph.1885DOI Listing
June 2021

Superionic Conductivity in Ceria-Based Heterostructure Composites for Low-Temperature Solid Oxide Fuel Cells.

Nanomicro Lett 2020 Aug 29;12(1):178. Epub 2020 Aug 29.

Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology/Energy Storage Research Center, School of Energy and Environment, Southeast University, Nanjing, 210096, People's Republic of China.

Ceria-based heterostructure composite (CHC) has become a new stream to develop advanced low-temperature (300-600 °C) solid oxide fuel cells (LTSOFCs) with excellent power outputs at 1000 mW cm level. The state-of-the-art ceria-carbonate or ceria-semiconductor heterostructure composites have made the CHC systems significantly contribute to both fundamental and applied science researches of LTSOFCs; however, a deep scientific understanding to achieve excellent fuel cell performance and high superionic conduction is still missing, which may hinder its wide application and commercialization. This review aims to establish a new fundamental strategy for superionic conduction of the CHC materials and relevant LTSOFCs. This involves energy band and built-in-field assisting superionic conduction, highlighting coupling effect among the ionic transfer, band structure and alignment impact. Furthermore, theories of ceria-carbonate, e.g., space charge and multi-ion conduction, as well as new scientific understanding are discussed and presented for functional CHC materials.
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http://dx.doi.org/10.1007/s40820-020-00518-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770899PMC
August 2020

Global Graph Attention Embedding Network for Relation Prediction in Knowledge Graphs.

IEEE Trans Neural Netw Learn Syst 2021 Jun 11;PP. Epub 2021 Jun 11.

The incompleteness of knowledge graphs triggers considerable research interest in relation prediction. As the key to predicting relations among entities, many efforts have been devoted to learning the embeddings of entities and relations by incorporating a variety of neighbors' information which includes not only the information from direct outgoing and incoming neighbors but also the ones from the indirect neighbors on the multihop paths. However, previous models usually consider entity paths of limited length or ignore sequential information of the paths. Either simplification will make the model lack a global understanding of knowledge graphs and may result in the loss of important and indispensable information. In this article, we propose a novel global graph attention embedding network (GGAE) for relation prediction by combining global information from both direct neighbors and multihop neighbors. Concretely, given a knowledge graph, we first introduce the path construction algorithms to obtain meaningful paths, then design path modeling methods to capture the potential long-distance sequential information in the multihop paths, final propose an entity graph attention and a relation graph attention mechanisms to obtain entity embeddings and relation embeddings. Moreover, an entity graph attention mechanism is proposed to calculate the entity embeddings by aggregating direct incoming and outgoing neighbors from: 1) an original knowledge graph with the original entity and relation embeddings and 2) a new knowledge graph constructed by the paths whose embeddings are updated by path modeling methods. for each relation, we construct a new graph with related entities and present a relation graph attention to learn the features. Therefore, our model can encapsulate the information from different distance neighbors, and enable the embeddings of entities and relations to better capture all-sided semantic information. The experimental results on benchmark datasets verify the superiority of our model over the state-of-the-art ones.
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http://dx.doi.org/10.1109/TNNLS.2021.3083259DOI Listing
June 2021

Humoral immune response to circulating SARS-CoV-2 variants elicited by inactivated and RBD-subunit vaccines.

Cell Res 2021 07 21;31(7):732-741. Epub 2021 May 21.

School of Pharmaceutical Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, China.

SARS-CoV-2 variants could induce immune escape by mutations on the receptor-binding domain (RBD) and N-terminal domain (NTD). Here we report the humoral immune response to circulating SARS-CoV-2 variants, such as 501Y.V2 (B.1.351), of the plasma and neutralizing antibodies (NAbs) elicited by CoronaVac (inactivated vaccine), ZF2001 (RBD-subunit vaccine) and natural infection. Among 86 potent NAbs identified by high-throughput single-cell VDJ sequencing of peripheral blood mononuclear cells from vaccinees and convalescents, near half anti-RBD NAbs showed major neutralization reductions against the K417N/E484K/N501Y mutation combination, with E484K being the dominant cause. VH3-53/VH3-66 recurrent antibodies respond differently to RBD variants, and K417N compromises the majority of neutralizing activity through reduced polar contacts with complementarity determining regions. In contrast, the 242-244 deletion (242-244Δ) would abolish most neutralization activity of anti-NTD NAbs by interrupting the conformation of NTD antigenic supersite, indicating a much less diversity of anti-NTD NAbs than anti-RBD NAbs. Plasma of convalescents and CoronaVac vaccinees displayed comparable neutralization reductions against pseudo- and authentic 501Y.V2 variants, mainly caused by E484K/N501Y and 242-244Δ, with the effects being additive. Importantly, RBD-subunit vaccinees exhibit markedly higher tolerance to 501Y.V2 than convalescents, since the elicited anti-RBD NAbs display a high diversity and are unaffected by NTD mutations. Moreover, an extended gap between the third and second doses of ZF2001 leads to better neutralizing activity and tolerance to 501Y.V2 than the standard three-dose administration. Together, these results suggest that the deployment of RBD-vaccines, through a third-dose boost, may be ideal for combating SARS-CoV-2 variants when necessary, especially for those carrying mutations that disrupt the NTD supersite.
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http://dx.doi.org/10.1038/s41422-021-00514-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8138844PMC
July 2021

Study on the Relationship between the miRNA-centered ceRNA Regulatory Network and Fatigue.

J Mol Neurosci 2021 May 16. Epub 2021 May 16.

College of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

In recent years, the incidence of fatigue has been increasing, and the effective prevention and treatment of fatigue has become an urgent problem. As a result, the genetic research of fatigue has become a hot spot. Transcriptome-level regulation is the key link in the gene regulatory network. The transcriptome includes messenger RNAs (mRNAs) and noncoding RNAs (ncRNAs). MRNAs are common research targets in gene expression profiling. Noncoding RNAs, including miRNAs, lncRNAs, circRNAs and so on, have been developed rapidly. Studies have shown that miRNAs are closely related to the occurrence and development of fatigue. MiRNAs can regulate the immune inflammatory reaction in the central nervous system (CNS), regulate the transmission of nerve impulses and gene expression, regulate brain development and brain function, and participate in the occurrence and development of fatigue by regulating mitochondrial function and energy metabolism. LncRNAs can regulate dopaminergic neurons to participate in the occurrence and development of fatigue. This has certain value in the diagnosis of chronic fatigue syndrome (CFS). CircRNAs can participate in the occurrence and development of fatigue by regulating the NF-κB pathway, TNF-α and IL-1β. The ceRNA hypothesis posits that in addition to the function of miRNAs in unidirectional regulation, mRNAs, lncRNAs and circRNAs can regulate gene expression by competitive binding with miRNAs, forming a ceRNA regulatory network with miRNAs. Therefore, we suggest that the miRNA-centered ceRNA regulatory network is closely related to fatigue. At present, there are few studies on fatigue-related ncRNA genes, and most of these limited studies are on miRNAs in ncRNAs. However, there are a few studies on the relationship between lncRNAs, cirRNAs and fatigue. Less research is available on the pathogenesis of fatigue based on the ceRNA regulatory network. Therefore, exploring the complex mechanism of fatigue based on the ceRNA regulatory network is of great significance. In this review, we summarize the relationship between miRNAs, lncRNAs and circRNAs in ncRNAs and fatigue, and focus on exploring the regulatory role of the miRNA-centered ceRNA regulatory network in the occurrence and development of fatigue, in order to gain a comprehensive, in-depth and new understanding of the essence of the fatigue gene regulatory network.
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http://dx.doi.org/10.1007/s12031-021-01845-3DOI Listing
May 2021

Membrane Lipids' Metabolism and Transcriptional Regulation in Maize Roots Under Cold Stress.

Front Plant Sci 2021 15;12:639132. Epub 2021 Apr 15.

Key Lab of Modern Agricultural Cultivation and Crop Germplasm Improvement of Heilongjiang Province, College of Agriculture, Heilongjiang Bayi Agricultural University, Daqing, China.

Low temperature is one of the major abiotic stresses that restrict the growth and development of maize seedlings. Membrane lipid metabolism and remodeling are key strategies for plants to cope with temperature stresses. In this study, an integrated lipidomic and transcriptomic analysis was performed to explore the metabolic changes of membrane lipids in the roots of maize seedlings under cold stress (5°C). The results revealed that major extraplastidic phospholipids [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA), and phosphatidylinositol (PI)] were dominant membrane lipids in maize root tissues, accounting for more than 70% of the total lipids. In the transcriptome data of maize roots under cold stress, a total of 189 lipid-related differentially expressed genes (DEGs) were annotated and classified into various lipid metabolism pathways, and most of the DEGs were enriched in the "Eukaryotic phospholipid synthesis" (12%), "Fatty acid elongation" (12%), and "Phospholipid signaling" (13%) pathways. Under low temperature stress, the molar percentage of the most abundant phospholipid PC decreased around 10%. The significantly up-regulated expression of genes encoding phospholipase [phospholipase D (PLD)] and phosphatase PAP/LPP genes implied that PC turnover was triggered by cold stress mainly the PLD pathway. Consequently, as the central product of PC turnover, the level of PA increased drastically (63.2%) compared with the control. The gene-metabolite network and co-expression network were constructed with the prominent lipid-related DEGs to illustrate the modular regulation of metabolic changes of membrane lipids. This study will help to explicate membrane lipid remodeling and the molecular regulation mechanism in field crops encountering low temperature stress.
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http://dx.doi.org/10.3389/fpls.2021.639132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8083060PMC
April 2021

Mechanism and toxicity evaluation of catalytic ozonation over Cu/Ce-AlO system aiming at degradation of humic acid in real wastewater.

Sci Rep 2021 Apr 22;11(1):8748. Epub 2021 Apr 22.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China.

Humic acid (HA) is the main component of organic matter in effluent from wastewater treatment. The effective removal of HA is significant. In this study, a novel catalyst was prepared using a transition metal oxide as the active component and AlO as a granular carrier. The mechanism of catalytic ozonation of HA under neutral pH conditions and its efficiency were investigated. Under the chosen conditions (an ozone concentration of 2.2 mg/L, 50 mg/L HA solution, catalyst dosage of 5 g/L and initial pH of 6.49), the Cu/Ce-AlO bimetallic catalyst led to 54.79% TOC removal rate after 30 min; the removal rate by ozone alone was only 20.49%. The characteristics of organic compounds determined by FT-IR and GC-MS showed that organic compounds were degraded significantly by the catalytic treatment. The addition of catalysts could effectively degrade toxic intermediates and reduce the acute toxicity produced by ozonation. Humic acid substances were largely removed and transformed into biodegradable intermediates. This study proposes a new and efficient ozonation catalyst for practical applications in advanced wastewater treatment.
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http://dx.doi.org/10.1038/s41598-021-83804-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062596PMC
April 2021

Stronger association of triglyceride glucose index than the HOMA-IR with arterial stiffness in patients with type 2 diabetes: a real-world single-centre study.

Cardiovasc Diabetol 2021 04 22;20(1):82. Epub 2021 Apr 22.

Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Background: The triglyceride-glucose index (TyG index) has been proposed as a simple and reliable alternative insulin resistance (IR) marker, while the homeostasis model assessment for IR (HOMA-IR) is the most frequently used index. Few studies have evaluated the role of IR assessed by the TyG index and HOMA-IR on arterial stiffness in a type 2 diabetes (T2D) population with a high risk of increased arterial stiffness. We aimed to investigate the association of the TyG index and HOMA-IR with arterial stiffness in patients with T2D.

Methods: We recruited 3185 patients with T2D, who underwent brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, but without previous cardiovascular disease. Increased arterial stiffness was defined as a baPWV value greater than the 75th percentile (18.15 m/s) in the present study. The TyG index was determined as ln(fasting triglycerides [mg/dL] × fasting glucose [mg/dL]/2), and the HOMA-IR was calculated as (fasting insulin [μIU/mL] × fasting glucose [mmol/L])/22.5.

Results: The mean age of the study participants was 54.6 ± 12.0 years, and 1954 (61.4%) were men. Seemingly unrelated regression estimation analysis demonstrated that the TyG index had stronger associations with baPWV than the HOMA-IR (all P < 0.001). In the multivariable logistic analyses, each one-unit increase in the TyG index was associated with a 1.40-fold (95% CI 1.16-1.70, P < 0.001) higher prevalence of increased arterial stiffness, but the prominent association of the HOMA-IR with the prevalence of increased arterial stiffness was not observed. Subgroup analyses showed that a more significant association between the TyG index and the prevalence of increased arterial stiffness was detected in older patients with a longer duration of diabetes and poor glycaemic control (all P < 0.05).

Conclusions: Compared with the HOMA-IR, the TyG index is independently and more strongly associated with arterial stiffness in patients with T2D.
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http://dx.doi.org/10.1186/s12933-021-01274-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8063289PMC
April 2021

Electrically reconfigurable non-volatile metasurface using low-loss optical phase-change material.

Nat Nanotechnol 2021 Jun 19;16(6):661-666. Epub 2021 Apr 19.

Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

Active metasurfaces promise reconfigurable optics with drastically improved compactness, ruggedness, manufacturability and functionality compared to their traditional bulk counterparts. Optical phase-change materials (PCMs) offer an appealing material solution for active metasurface devices with their large index contrast and non-volatile switching characteristics. Here we report a large-scale, electrically reconfigurable non-volatile metasurface platform based on optical PCMs. The optical PCM alloy used in the devices, GeSbSeTe (GSST), uniquely combines giant non-volatile index modulation capability, broadband low optical loss and a large reversible switching volume, enabling notably enhanced light-matter interactions within the active optical PCM medium. Capitalizing on these favourable attributes, we demonstrated quasi-continuously tuneable active metasurfaces with record half-octave spectral tuning range and large optical contrast of over 400%. We further prototyped a polarization-insensitive phase-gradient metasurface to realize dynamic optical beam steering.
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http://dx.doi.org/10.1038/s41565-021-00881-9DOI Listing
June 2021

Association of Metabolic Syndrome With Prevalence of Obstructive Sleep Apnea and Remission After Sleeve Gastrectomy.

Front Physiol 2021 31;12:650260. Epub 2021 Mar 31.

Department of Endocrine and Metabolic Diseases, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Obesity is an important risk factor for metabolic syndrome and obstructive sleep apnea (OSA). Bariatric surgery has been shown to effectively reduce weight and obesity-related comorbidities. However, the prevalence and severity of OSA in obese patients with different baseline metabolic states and the improvements of OSA after bariatric surgery remain unknown. The main aims of this study were to ascertain the prevalence of OSA in young Chinese obese patients with different metabolic states and to evaluate their respective OSA remission after laparoscopic sleeve gastrectomy. We first performed a cross-sectional study involving 123 metabolically healthy obese patients and 200 metabolically unhealthy obese patients (who had the same age and BMI ranges) to estimate the prevalence of OSA at baseline. Then we performed a retrospective study, which was registered at ClinicalTrials.gov (ref. NCT02653430) of 67 patients who underwent laparoscopic sleeve gastrectomy to evaluate the remission of OSA. Metabolically healthy and unhealthy obese patients had similar apnea-hypopnea index levels (16.6 ± 22.0 vs. 16.7 ± 18.7 events/h, = 0.512) and prevalence of OSA (66.7% vs. 69.0%, = 0.662). Male sex, age, waist circumference and lower liver-to-spleen ratio were independent risk factors for OSA. After laparoscopic sleeve gastrectomy, no difference was found in the decrease in body mass index (BMI) change (10.8 ± 4.8 vs. 10.8 ± 3.0 kg/m, = 0.996) or the decrease in the apnea-hypopnea index (18.9 ± 24.6 vs. 17.0 ± 24.0 events/h, = 0.800). The remission of moderate-to-severe OSA was observed in the MHO (36.3%; 54.5-18.2%, = 0.125) and MUO (32.2%; 66.1-33.9%, = 0.001) patients. These results suggest that, in patients with obesity, metabolic syndrome does not add extra risk for the prevalence or severity of OSA. Both metabolically healthy and unhealthy obese patients could benefit equally from laparoscopic sleeve gastrectomy in terms of weight loss and obstructive sleep apnea remission.
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http://dx.doi.org/10.3389/fphys.2021.650260DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8044302PMC
March 2021

A simple new method for aged seed utilization based on melatonin-mediated germination and antioxidant nutrient production.

Sci Rep 2021 Mar 15;11(1):5937. Epub 2021 Mar 15.

Heilongjiang Higher Educational Key Laboratory for Cold-Regional Crop Cultivation and Germplasm Improvement, Department of Agronomy, Heilongjiang Bayi Agricultural University, No. 2, Xinyang Road, High-Tech Development Zone of Daqing, Daqing, 163319, China.

Seed deterioration, coupled with a decrease in nutrients, is unavoidable following long-term storage, and these seeds are therefore used as livestock fodder. Here, we developed a simple, rapid and efficient method of producing high amounts of antioxidants from deteriorated seeds via melatonin-induced germination. Legume seeds were subjected to high humidity at 55 °C for 12-36 h to obtain aged seeds with a 40% germination rate and severely reduced antioxidant nutrition (total phenolics content, ferric reducing power and 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging capacity). Aged seeds were then treated with 0.1 mM melatonin, resulting in the production of sprouts with a higher total phenolics content (fivefold), greater ferric reducing power (sevenfold) and greater DPPH radical scavenging capacity (twofold) compared to the aged seeds. These findings suggest that melatonin treatment efficiently converted aged seed reserve residues into antioxidant nutrients, providing an alternative use for deteriorated seeds in food production.
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http://dx.doi.org/10.1038/s41598-021-85541-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7971019PMC
March 2021

Feasibility of nanoscale zerovalent iron-loaded sediment-based biochar (nZVI-SBC) for simultaneous removal of nitrate and phosphate: high selectivity toward dinitrogen and synergistic mechanism.

Environ Sci Pollut Res Int 2021 Jul 13;28(28):37448-37458. Epub 2021 Mar 13.

College of Architecture Engineering, Beijing University of Technology, 100 Pingleyuan, Chaoyang district, Beijing, 100124, China.

In the process of water treatment, excessive nitrogen and phosphorus pollutants are of great concern. Therefore, we prepared nanoscale zerovalent iron loaded on sediment-based biochar (nZVI-SBC) to conduct nitrate and phosphate removal at the same time. The characterization demonstrated that nZVI-SBC was successfully synthesized, which had obvious advantages for larger specific surface area and better dispersion compared with pure nZVI. The batch experiments indicated that the best loading ratio of nZVI to SBC and optimum dosage for nitrate and phosphate were 1:1and 2 g L, respectively. Their removal by nZVI-SBC was an acid-driven process. Anoxic environment was more conducive to the reduction of nitrate while the phosphate removal was fond of oxygen environment. A total of 77.78% of nitrate and 99.21% of phosphate have been successfully removed, mainly depending on reduction and complexation mechanism, respectively. Moreover, nZVI-SBC had higher N selectivity and produced less ammonium than nZVI. The interaction between nitrate and phosphate was studied to manifest that they had different degrees of inhibition during the removal of the other. Our research indicated that nZVI-SBC has great potential for remediation of nitrogen and phosphorus polluted water.
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http://dx.doi.org/10.1007/s11356-021-13322-wDOI Listing
July 2021

Enhanced Electrical Properties of Lithography-Free Fabricated MoS Field Effect Transistors with Chromium Contacts.

J Phys Chem Lett 2021 Mar 11;12(11):2705-2711. Epub 2021 Mar 11.

Department of Materials Science, Fudan University, Shanghai 200433, P.R. China.

Molybdenum disulfide (MoS) as a two-dimensional semiconductor material has been actively explored for field-effect-transistors (FETs). The current prevailing method for MoS FET fabrication involves multiple complex steps, including electron beam (e-beam) lithography, annealing, ., which are time-consuming and require polymer resists. As a consequence, the MoS exposed to chemicals during the patterning process may be unfavorably affected by residues and the performance of the final FET could be impaired while the annealing limits materials for FETs. Therefore, there is an urgent need to free the fabrication of FETs from e-beam lithography and annealing. In this study, we introduce an e-beam lithography-free method to fabricate MoS FETs by employing maze-like source/drain electrodes. In addition, an ohmic contact in multilayer MoS FETs using chromium (Cr) as source/drain electrodes is achieved without annealing. The underlying mechanism for contact performance is studied, and the tightness of the contact and the type of metal are found to be responsible because they determine the contact resistance. Furthermore, the long-term device degradation is explored, in which the oxidation of metal dominates. The facile fabrication process and mechanism explanation in this work might provide a new platform for future electronic devices.
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http://dx.doi.org/10.1021/acs.jpclett.1c00231DOI Listing
March 2021

An association between body image dissatisfaction and digit ratio among Chinese children and adolescents.

Sci Rep 2021 Mar 4;11(1):5217. Epub 2021 Mar 4.

Department of Child and Adolescent Health, School of Public Health, Bengbu Medical College, No. 2600 East Sea Avenue, Bengbu, 233030, Anhui, People's Republic of China.

Body image dissatisfaction (BID) is a negative evaluation of personal physical characteristics, including dissatisfaction with body shape, gender, sexual organs, appearance and so forth, and it plays an important role in growth and development. The second-to-fourth digit ratio (2D:4D) is recognized as a putative indicator of intra-uterine testosterone to estrogen ratio exposure, and it has been observed that higher levels of fetal testosterone exposure are associated with a lower 2D:4D. The present paper contributes to a better understanding of the biological underpinnings of BID by analyzing BID and the digit ratio (2D:4D). We found that the 2D:4D was positively related to appearance dissatisfaction in boys with first spermatorrhea, which means that low prenatal androgen exposure may increase boys' dissatisfaction with their appearance. In girls with breast development being lower than Tanner stage II, their 2D:4D was negatively related to their body shape dissatisfaction, which means that high prenatal androgen exposure may increase girls' dissatisfaction with their body shape. These results suggest that the prenatal androgen exposure level might play an important role in the body image dissatisfaction of the offspring.
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http://dx.doi.org/10.1038/s41598-021-84711-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7970844PMC
March 2021

Active Modulation of an All-Dielectric Metasurface Analogue of Electromagnetically Induced Transparency in Terahertz.

ACS Omega 2021 Feb 4;6(6):4480-4484. Epub 2021 Feb 4.

School of Microelectronics, Shandong University, Jinan 250100, China.

In this work, an analogue of electromagnetically induced transparency (EIT) is excited by a periodic unit consisting of a silicon rectangular bar resonator and a silicon ring resonator in terahertz (THz). The analogue of the EIT effect can be well excited by coupling of the "bright mode" and the "dark mode" supported by the bar and the ring, respectively. Using the semimetallic properties of graphene, active control of the EIT-like effect can be realized by integrating a monolayer graphene into THz metamaterials. By adjusting the Fermi energy of graphene, the resonating electron distribution changes in the dielectric structures, resulting in the varying of the EIT-like effect. The transmission can be modulated from 0.9 to 0.3 with the Fermi energy of graphene placed under the ring resonator mold varying from 0 to 0.6 eV, while a modulation range of 0.9-0.3 corresponds to Fermi energy from 0 to 0.3 eV when graphene is placed under the rectangular bar resonator. Our results may provide potential applications in slow light devices and an ultrafast optical signal.
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http://dx.doi.org/10.1021/acsomega.0c06082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906593PMC
February 2021

Reconfigurable all-dielectric metalens with diffraction-limited performance.

Nat Commun 2021 Feb 22;12(1):1225. Epub 2021 Feb 22.

Department of Materials Science & Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

Active metasurfaces, whose optical properties can be modulated post-fabrication, have emerged as an intensively explored field in recent years. The efforts to date, however, still face major performance limitations in tuning range, optical quality, and efficiency, especially for non-mechanical actuation mechanisms. In this paper, we introduce an active metasurface platform combining phase tuning in the full 2π range and diffraction-limited performance using an all-dielectric, low-loss architecture based on optical phase change materials (O-PCMs). We present a generic design principle enabling binary switching of metasurfaces between arbitrary phase profiles and propose a new figure-of-merit (FOM) tailored for reconfigurable meta-optics. We implement the approach to realize a high-performance varifocal metalens operating at 5.2 μm wavelength. The reconfigurable metalens features a record large switching contrast ratio of 29.5 dB. We further validate aberration-free and multi-depth imaging using the metalens, which represents a key experimental demonstration of a non-mechanical tunable metalens with diffraction-limited performance.
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http://dx.doi.org/10.1038/s41467-021-21440-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7900249PMC
February 2021

Water enables mild oxidation of methane to methanol on gold single-atom catalysts.

Nat Commun 2021 Feb 22;12(1):1218. Epub 2021 Feb 22.

Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, P. R. China.

As a 100% atom-economy process, direct oxidation of methane into methanol remains as a grand challenge due to the dilemma between activation of methane and over-oxidation of methanol. Here, we report that water enabled mild oxidation of methane into methanol with >99% selectivity over Au single atoms on black phosphorus (Au/BP) nanosheets under light irradiation. The mass activity of Au/BP nanosheets reached 113.5 μmol g in water pressured with 33 bar of mixed gas (CH:O = 10:1) at 90 °C under light irradiation (1.2 W), while the activation energy was 43.4 kJ mol. Mechanistic studies revealed that water assisted the activation of O to generate reactive hydroxyl groups and •OH radicals under light irradiation. Hydroxyl groups reacted with methane at Au single atoms to form water and CH* species, followed by oxidation of CH* via •OH radicals into methanol. Considering the recycling of water during the whole process, we can also regard water as a catalyst.
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http://dx.doi.org/10.1038/s41467-021-21482-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7900127PMC
February 2021

Self-adhesive lubricated coating for enhanced bacterial resistance.

Bioact Mater 2021 Aug 4;6(8):2535-2545. Epub 2021 Feb 4.

State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing, 100084, China.

Limited surface lubrication and bacterial biofilm formation pose great challenges to biomedical implants. Although hydrophilic lubricated coatings and bacterial resistance coatings have been reported, the harsh and tedious synthesis greatly compromises their application, and more importantly, the bacterial resistance property has seldom been investigated in combination with the lubrication property. In this study, bioinspired by the performances of mussel and articular cartilage, we successfully synthesized self-adhesive lubricated coating and simultaneously achieved optimal lubrication and bacterial resistance properties. Additionally, we reported the mechanism of bacterial resistance on the nanoscale by studying the adhesion interactions between biomimetic coating and hydrophilic/hydrophobic tip or living bacteria via atomic force microscopy. In summary, the self-adhesive lubricated coating can effectively enhance lubrication and bacterial resistance performances based on hydration lubrication and hydration repulsion, and represent a universal and facial strategy for surface functionalization of biomedical implants.
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http://dx.doi.org/10.1016/j.bioactmat.2021.01.028DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7868611PMC
August 2021

Prenatal and perinatal home environment and reported onset of wheeze, rhinitis and eczema symptoms in preschool children in Northern China.

Sci Total Environ 2021 Jun 6;774:145700. Epub 2021 Feb 6.

School of Public Health, Fudan University, Shanghai, China.

Early life environment can affect asthma and allergies but few cohort studies on this issue are available from China. Our aim was to investigate reported onset of childhood wheeze, rhinitis and eczema symptoms in relation to prenatal, perinatal and postnatal home environment. Data on home environment and symptoms (ISAAC based questions) in first two years of life and in the past 12 months were reported by parents of the children (3-6 y) in a cross-sectional questionnaire survey in ten day care centers in Taiyuan, northern China (N = 3606). Changes of symptoms from the first 2 years of life to the past 12 months (recall period) were calculated retrospectively. Multilevel logistic regression analysis was applied. Reported onset of wheeze, rhinitis and eczema were 11.8%, 22.2% and 3.3%, respectively. Redecorating during pregnancy increased reported onset of rhinitis (OR = 2.29) and eczema (OR = 4.91). New furniture during pregnancy increased reported onset of rhinitis (OR = 1.47). Perinatal indoor mould increased reported onset of wheeze (OR = 1.51), rhinitis (OR = 1.65) and eczema (OR = 1.91). Perinatal mould odour increased reported onset of wheeze (OR = 1.85). Perinatal window pane condensation increased reported onset of wheeze (OR = 1.54) and rhinitis (OR = 1.24). Perinatal stuffy air and dry air in the home increased reported onset of all three symptoms (ORs 1.46-2.24). Dog keeping increased reported onset of wheeze (OR = 1.69) and eczema (OR = 2.13). Based on principal component analysis, four exposure scores were calculated (renovation, new furniture, mould and indoor air quality scores). Dose-response relationships were observed between these exposure scores and reported onset of symptoms. In conclusion, prenatal and postnatal exposure to emissions from renovation and new furniture can increase reported onset of childhood wheeze, rhinitis and eczema. Perinatal indoor mould, mould odour, condensation on window panes and impaired indoor air quality at home can be associated with reported development of wheeze, rhinitis and eczema in preschoolers in northern China.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145700DOI Listing
June 2021

Insight-HXMT observations of jet-like corona in a black hole X-ray binary MAXI J1820+070.

Nat Commun 2021 Feb 15;12(1):1025. Epub 2021 Feb 15.

Department of Physics, Tsinghua University, Beijing, PR China.

A black hole X-ray binary produces hard X-ray radiation from its corona and disk when the accreting matter heats up. During an outburst, the disk and corona co-evolves with each other. However, such an evolution is still unclear in both its geometry and dynamics. Here we report the unusual decrease of the reflection fraction in MAXI J1820+070, which is the ratio of the coronal intensity illuminating the disk to the coronal intensity reaching the observer, as the corona is observed to contrast during the decay phase. We postulate a jet-like corona model, in which the corona can be understood as a standing shock where the material flowing through. In this dynamical scenario, the decrease of the reflection fraction is a signature of the corona's bulk velocity. Our findings suggest that as the corona is observed to get closer to the black hole, the coronal material might be outflowing faster.
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http://dx.doi.org/10.1038/s41467-021-21169-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884741PMC
February 2021

Confined Generation of Homogeneously Dispersed Au and SnO Nanoparticles in Layered Silicate as Synergistic Catalysts.

Langmuir 2021 Feb 9;37(7):2341-2348. Epub 2021 Feb 9.

Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University, Beijing 100191, PR China.

With the aid of the confined conversion of layered silicate RUB-15, homogeneously dispersed Au and SnO nanoparticles (NPs) were generated in the confined layer space of RUB-15. The Au-SnO/SiO composite was obtained with the structure that ultrafine Au and SnO NPs were supported on SiO lamellas. Benefited by the Sn(II)-assisted in situ reduction strategy, Au NPs were highly uniformed and evenly distributed in/on the RUB-15. This Au-SnO/SiO composite was employed as a catalyst to the reduction of 4-nitrophenol showing excellent catalytic activity. The catalytic rate constant at room temperature was calculated to be 6.64 min, which was dramatically higher than that of Au/SiO composite produced by reduction with hydrazine hydrate on the same support of layered silicate RUB-15. The interaction between Au and SnO NPs increased the electron density around Au NPs, which was demonstrated to be an essential factor to the excellent catalytic activity of the Au-SnO/SiO composite. The simple and universal synthesis method afforded precise control over the size/spatial arrangement of Au and SnO NPs on SiO lamellas. The high activity of the Au-SnO/SiO composite demonstrated that the strategy used in this study has good potential application prospect. Furthermore, this work provided new perspective on the catalysis mechanism to the metal/semiconductor synergistic catalyst system.
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http://dx.doi.org/10.1021/acs.langmuir.0c03216DOI Listing
February 2021

The complete chloroplast genome of (W.C. Cheng) H.S. Kiu (Loranthaceae), a hemiparasitic shrub.

Mitochondrial DNA B Resour 2021 Jan 27;6(1):282-284. Epub 2021 Jan 27.

CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Menglun, China.

(W.C. Cheng) H.S. Kiu is a stem hemiparasite of the genus in the family Loranthaceae distributed in southwest China and northern Vietnam. Here, we report and characterize the complete plastid genome sequence of to provide genomic resources useful for the phylogenetic studies of Santalales. The plastome of is 122,764 bp in length, consisted of a large single-copy region (70,726 bp), a small single-copy region (6,091 bp), and a pair of inverted repeat regions (22,974 bp). The GC content of the whole plastome is 37.2%. It contains 109 genes, including 69 CDS (protein-coding genes), eight rRNAs, and 32 tRNAs. The alignment of 14 species complete chloroplast genomes of Loranthaceae was implemented and a phylogenetic tree was constructed using maximum-likelihood (ML) method, which revealed that . clustered with and as a monophyletic group.
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http://dx.doi.org/10.1080/23802359.2020.1863166DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7850402PMC
January 2021

Altered Weibull Degree Distribution in Resting-State Functional Brain Networks Is Associated With Cognitive Decline in Mild Cognitive Impairment.

Front Aging Neurosci 2020 5;12:599112. Epub 2021 Jan 5.

Dementia Care and Research Center, Peking University Institute of Mental Health (Sixth Hospital), Beijing, China.

The topological organization of human brain networks can be mathematically characterized by the connectivity degree distribution of network nodes. However, there is no clear consensus on whether the topological structure of brain networks follows a power law or other probability distributions, and whether it is altered in Alzheimer's disease (AD). Here we employed resting-state functional MRI and graph theory approaches to investigate the fitting of degree distributions of the whole-brain functional networks and seven subnetworks in healthy subjects and individuals with amnestic mild cognitive impairment (aMCI), i.e., the prodromal stage of AD, and whether they are altered and correlated with cognitive performance in patients. Forty-one elderly cognitively healthy controls and 30 aMCI subjects were included. We constructed functional connectivity matrices among brain voxels and examined nodal degree distributions that were fitted by maximum likelihood estimation. In the whole-brain networks and all functional subnetworks, the connectivity degree distributions were fitted better by the Weibull distribution [f(x)~xe] than power law or power law with exponential cutoff. Compared with the healthy control group, the aMCI group showed lower Weibull β parameters (shape factor) in both the whole-brain networks and all seven subnetworks (false-discovery rate-corrected, < 0.05). These decreases of the Weibull β parameters in the whole-brain networks and all subnetworks except for ventral attention were associated with reduced cognitive performance in individuals with aMCI. Thus, we provided a short-tailed model to capture intrinsic connectivity structure of the human brain functional networks in health and disease.
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http://dx.doi.org/10.3389/fnagi.2020.599112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7814317PMC
January 2021
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