Publications by authors named "Yuan Cao"

374 Publications

Entropic evidence for a Pomeranchuk effect in magic-angle graphene.

Nature 2021 Apr 7;592(7853):214-219. Epub 2021 Apr 7.

Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel.

In the 1950s, Pomeranchuk predicted that, counterintuitively, liquid He may solidify on heating. This effect arises owing to high excess nuclear spin entropy in the solid phase, where the atoms are spatially localized. Here we find that an analogous effect occurs in magic-angle twisted bilayer graphene. Using both local and global electronic entropy measurements, we show that near a filling of one electron per moiré unit cell, there is a marked increase in the electronic entropy to about 1k per unit cell (k is the Boltzmann constant). This large excess entropy is quenched by an in-plane magnetic field, pointing to its magnetic origin. A sharp drop in the compressibility as a function of the electron density, associated with a reset of the Fermi level back to the vicinity of the Dirac point, marks a clear boundary between two phases. We map this jump as a function of electron density, temperature and magnetic field. This reveals a phase diagram that is consistent with a Pomeranchuk-like temperature- and field-driven transition from a low-entropy electronic liquid to a high-entropy correlated state with nearly free magnetic moments. The correlated state features an unusual combination of seemingly contradictory properties, some associated with itinerant electrons-such as the absence of a thermodynamic gap, metallicity and a Dirac-like compressibility-and others associated with localized moments, such as a large entropy and its disappearance under a magnetic field. Moreover, the energy scales characterizing these two sets of properties are very different: whereas the compressibility jump has an onset at a temperature of about 30 kelvin, the bandwidth of magnetic excitations is about 3 kelvin or smaller. The hybrid nature of the present correlated state and the large separation of energy scales have implications for the thermodynamic and transport properties of the correlated states in twisted bilayer graphene.
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http://dx.doi.org/10.1038/s41586-021-03319-3DOI Listing
April 2021

Effects of Preoperative Anxiety on Postoperative Delirium in Elderly Patients Undergoing Elective Orthopedic Surgery: A Prospective Observational Cohort Study.

Clin Interv Aging 2021 26;16:549-557. Epub 2021 Mar 26.

Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, People's Republic of China.

Background: Postoperative delirium (POD) is common and has negative effects on elderly patients. There is a critical need to identify patients at high risk of POD so that providers can better offer targeted interventions in the preoperative and intraoperative periods. We aimed to characterize the prevalence of preoperative anxiety and investigate whether preoperative anxiety predicted the onset of POD in elderly patients undergoing elective orthopedic surgery.

Methods: We conducted a prospective observational cohort study of elderly patients (aged 65 years or older) undergoing elective orthopedic surgery. Preoperative anxiety was assessed using the Hospital Anxiety and Depression Scale-Anxiety (HADS-A), with clinically significant values defined as HADS-A>7. POD was diagnosed according to the Confusion Assessment Method (CAM) criteria on the 5 postoperative days. To determine the independent risk factors for POD, multivariable logistic regression was conducted, including those variables with a p-value <0.05 at univariate analysis.

Results: There were 263 patients included in the study. Seventy-three (27.8%) patients were diagnosed to be POD. Median duration of delirium was 2 days. Forty (15.2%) patients were assessed to experience preoperative anxiety. The occurrence of preoperative anxiety in total hip arthroplasty (THA), proximal femoral nail antirotation (PFNA), and total knee arthroplasty (TKA) was 12.5%, 16.1%, and 19.5%, respectively. Based on multivariable analysis, only age (odds ratio [OR]= 1.099, 95% Confidence Interval [CI]: 1.013-1.192; =0.023), Mini Mental State Examination (MMSE) (OR= 0.603, 95% CI: 0.432-0.842; =0.003) and preoperative anxiety (OR= 3.119, 95% CI: 1.144-8.500; =0.026) were independently associated with POD.

Conclusion: In conclusion, the current study reveals that preoperative anxiety helps to predict the risk of POD in elderly patients undergoing elective orthopedic surgery. Relieving preoperative anxiety could be a new target for preventive interventions to reduce POD.
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http://dx.doi.org/10.2147/CIA.S300639DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009348PMC
March 2021

Comparison of Postnatal Growth Charts of Singleton Preterm and Term Infants Using World Health Organization Standards at 40-160 Weeks Postmenstrual Age: A Chinese Single-Center Retrospective Cohort Study.

Front Pediatr 2021 15;9:595882. Epub 2021 Mar 15.

Department of Developmental Pediatrics and Child Health Care, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Shandong Engineering and Technology Research Center for Pediatric Drug Development, Jinan, China.

There remains controversy regarding whether the growth charts constructed from data of term infants, such as those produced by the World Health Organization (WHO) standards, can appropriately evaluate the postnatal growth of preterm infants. This retrospective cohort study, conducted in the First Affiliated Hospital of Shandong First Medical University in Jinan China, aimed to compare the postnatal growth charts of singleton preterm and term infants using WHO standards at 40-160 weeks postmenstrual age (PMA). A total of 5,459 and 15,185 sets of longitudinal measurements [length/height, weight, head circumference (HC), and body mass index (BMI)] from birth to 160 weeks PMA were used to construct growth charts for 559 singleton preterm (mean PMA at birth, 33.84 weeks) and 1,596 singleton term infants (born at 40 weeks PMA), respectively, using the Generalized Additive Models for Location, Scale, and Shape (GAMLSS) method. Z-scores (prematurity corrected) were calculated using WHO Anthro software. Compared to WHO standards, all parameters of preterm infants were increased, especially in terms of length/height and weight; the gap between the two almost spanned two adjacent centile curves. Compared to term controls, the length/height, weight, and BMI of preterm infants were higher at 40 weeks PMA, surpassed by term infants at 52-64 weeks PMA, and quite consistent thereafter. The HC of preterm infants at 40-160 weeks PMA was quite consistent with both term controls and the WHO standards. The Z-scores for length/height, weight, and BMI of preterm infants relative to the WHO standards gradually decreased from 1.20, 1.13, and 0.74 at 40-44 weeks PMA to 0.67, 0.42, and 0.03 at 132-160 weeks PMA, respectively; Z-scores for HC of preterm infants rapidly decreased from 0.73 to 0.29 at 40-50 weeks PMA, and then fluctuated in the range of 0.08-0.23 at 50-160 weeks PMA. Preterm infants had higher growth trajectories than the WHO standards and similar but not identical trajectories to term infants during the first 2 years of life. These findings reemphasize the necessity of constructing local growth charts for Chinese singleton preterm infants.
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http://dx.doi.org/10.3389/fped.2021.595882DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8005644PMC
March 2021

Flavour Hund's coupling, Chern gaps and charge diffusivity in moiré graphene.

Nature 2021 Apr 31;592(7852):43-48. Epub 2021 Mar 31.

Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.

Interaction-driven spontaneous symmetry breaking lies at the heart of many quantum phases of matter. In moiré systems, broken spin/valley 'flavour' symmetry in flat bands underlies the parent state from which correlated and topological ground states ultimately emerge. However, the microscopic mechanism of such flavour symmetry breaking and its connection to the low-temperature phases are not yet understood. Here we investigate the broken-symmetry many-body ground state of magic-angle twisted bilayer graphene (MATBG) and its nontrivial topology using simultaneous thermodynamic and transport measurements. We directly observe flavour symmetry breaking as pinning of the chemical potential at all integer fillings of the moiré superlattice, demonstrating the importance of flavour Hund's coupling in the many-body ground state. The topological nature of the underlying flat bands is manifested upon breaking time-reversal symmetry, where we measure energy gaps corresponding to Chern insulator states with Chern numbers 3, 2, 1 at filling factors 1, 2, 3, respectively, consistent with flavour symmetry breaking in the Hofstadter butterfly spectrum of MATBG. Moreover, concurrent measurements of resistivity and chemical potential provide the temperature-dependent charge diffusivity of MATBG in the strange-metal regime-a quantity previously explored only in ultracold atoms. Our results bring us one step closer to a unified framework for understanding interactions in the topological bands of MATBG, with and without a magnetic field.
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http://dx.doi.org/10.1038/s41586-021-03366-wDOI Listing
April 2021

Fast kNN Search in Weighted Hamming Space With Multiple Tables.

IEEE Trans Image Process 2021 5;30:3985-3994. Epub 2021 Apr 5.

Hashing methods have been widely used in Approximate Nearest Neighbor (ANN) search for big data due to low storage requirements and high search efficiency. These methods usually map the ANN search for big data into the k -Nearest Neighbor ( k NN) search problem in Hamming space. However, Hamming distance calculation ignores the bit-level distinction, leading to confusing ranking. In order to further increase search accuracy, various bit-level weights have been proposed to rank hash codes in weighted Hamming space. Nevertheless, existing ranking methods in weighted Hamming space are almost based on exhaustive linear scan, which is time consuming and not suitable for large datasets. Although Multi-Index hashing that is a sub-linear search method has been proposed, it relies on Hamming distance rather than weighted Hamming distance. To address this issue, we propose an exact k NN search approach with Multiple Tables in Weighted Hamming space named WHMT, in which the distribution of bit-level weights is incorporated into the multi-index building. By WHMT, we can get the optimal candidate set for exact k NN search in weighted Hamming space without exhaustive linear scan. Experimental results show that WHMT can achieve dramatic speedup up to 69.8 times over linear scan baseline without losing accuracy in weighted Hamming space.
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http://dx.doi.org/10.1109/TIP.2021.3066907DOI Listing
April 2021

The functional significance of cognitive empathy and theory of mind in early and chronic schizophrenia.

Psychiatry Res 2021 Mar 2;299:113852. Epub 2021 Mar 2.

Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China. Electronic address:

Theoretical models suggest that it is the interplay between social cognitive processes that result in adaptive social functioning in schizophrenia. This study explored the relative contributions of, and interplay between, cognitive empathy, affective theory of mind (ToM), neurocognition, and severity of clinical symptoms, in predicting the social functioning of individuals with schizophrenia. Clinical participants (early schizophrenia n = 26, chronic schizophrenia n = 32) were administered an ecologically valid measure of ToM (viz., the Virtual Assessment of Mentalising Ability or VAMA) and the Empathy Quotient (EQ) as part of a larger neuropsychological and social functioning assessment battery. Results indicated that individuals with early schizophrenia reported significantly better cognitive empathy than individuals with chronic schizophrenia. ToM was found to have added value in predicting both community functioning and functional capacity that was beyond that accounted for by cognitive empathy, clinical symptoms, and neurocognition for both clinical groups. Further, our results indicated that the capacity to demonstrate empathic understanding of another's situation (i.e., cognitive empathy) mediates the relationship between ToM and social functioning. Together, our findings highlight the intricate and compounding nature of social cognition constructs, and their effect on social functioning for individuals with schizophrenia.
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http://dx.doi.org/10.1016/j.psychres.2021.113852DOI Listing
March 2021

Comprehensive multiomics analysis of the effect of ginsenoside Rb1 on hyperlipidemia.

Aging (Albany NY) 2021 Mar 19;13. Epub 2021 Mar 19.

Key Laboratory of Ministry of Education for Traditional Chinese Medicine Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, People's Republic of China.

We analyzed the effects of ginsenoside Rb1 on hyperlipidemic in model mice. Using stool, plasma and hepatic tissue samples, we observed that the genera and were increased and was decrease in Rb1-treated mice as compared to untreated model mice. Ether lipid metabolism, glycerolipid metabolism, and glyoxylate and dicarboxylate metabolism were differentially enriched between the Rb1 and model groups. Lipidomics revealed 169 metabolites differentially expressed between the model and Rb1 groups in a positive ion model and 58 in a negative ion model. These metabolites mainly participate in glycerophospholipid, linoleic acid, and alpha-linolenic acid metabolism. The main metabolites enriched in these three pathways were phosphatidylcholine, diacylglycerol and ceramide, respectively. In a transcriptome analysis, 766 transcripts were differentially expressed between the Rb1 and model groups. KEGG analysis revealed lysine degradation, inositol phosphate metabolism, and glycerophospholipid metabolism to be the main enriched pathways. Multiomics analysis revealed glycerophospholipid metabolism to be a common pathway and phosphatidylcholine the main metabolite differentially enriched between the Rb1 and model groups. Results from fecal transplanted germ-free mice suggest that to suppress hyperlipidemia, Rb1 regulates gut microbiota by regulating the synthesis and decomposition of phosphatidylcholine in glycerophospholipid metabolism, which in turn decreases serum total cholesterol.
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http://dx.doi.org/10.18632/aging.202728DOI Listing
March 2021

Three-wavelength measurement of aerosol absorption using a multi-resonator coupled photoacoustic spectrometer.

Opt Express 2021 Jan;29(2):2258-2269

Aerosol optical absorption measurements are important for the prediction of climate change, as aerosols directly disturb Earth's radiation balance by absorbing or scattering solar radiation. Although photoacoustic spectroscopy is commonly recognized as one of the best candidates to measure the absorption of aerosols, multi-wavelength measurements of aerosols optical absorption remain challenging. Here, a method based on photoacoustic spectroscopy that can simultaneously measure the aerosol absorption characteristics of three wavelengths (404, 637 and 805 nm) is proposed. In the three-wavelength photoacoustic spectrometer (TW-PAS), a photoacoustic cell with three acoustic resonators operating at different resonant frequencies was designed for offering multi-laser (multi-wavelength) operation simultaneously, and only one microphone was used to measure the acoustic signals of all resonators. The performance of TW-PAS was demonstrated and evaluated by measuring and analyzing the wavelength-dependent absorption coefficients of carbonaceous aerosols, which shows good agreement with previously reported results. The developed TW-PAS exhibits high potential for classifying and quantifying different types of light-absorbing aerosols by analyzing its absorption wavelength dependence characteristics.
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http://dx.doi.org/10.1364/OE.412922DOI Listing
January 2021

X-ray-Based Techniques to Study the Nano-Bio Interface.

ACS Nano 2021 03 2;15(3):3754-3807. Epub 2021 Mar 2.

Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo de Miramon 182, 20014 Donostia San Sebastián, Spain.

X-ray-based analytics are routinely applied in many fields, including physics, chemistry, materials science, and engineering. The full potential of such techniques in the life sciences and medicine, however, has not yet been fully exploited. We highlight current and upcoming advances in this direction. We describe different X-ray-based methodologies (including those performed at synchrotron light sources and X-ray free-electron lasers) and their potentials for application to investigate the nano-bio interface. The discussion is predominantly guided by asking how such methods could better help to understand and to improve nanoparticle-based drug delivery, though the concepts also apply to nano-bio interactions in general. We discuss current limitations and how they might be overcome, particularly for future use .
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http://dx.doi.org/10.1021/acsnano.0c09563DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992135PMC
March 2021

Temozolomide Treatment Induces HMGB1 to Promote the Formation of Glioma Stem Cells via the TLR2/NEAT1/Wnt Pathway in Glioblastoma.

Front Cell Dev Biol 2021 1;9:620883. Epub 2021 Feb 1.

State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi'an, China.

Formation of glioma stem cells (GSCs) is considered as one of the main reasons of temozolomide (TMZ) resistance in glioma patients. Recent studies have shown that tumor microenvironment-derived signals could promote GSCs formation. But the critical molecule and underlying mechanism for GSCs formation after TMZ treatment is not entirely identified. Our study showed that TMZ treatment promoted GSCs formation by glioma cells; TMZ treatment of biopsy-derived glioblastoma multiforme cells upregulated HMGB1; HMGB1 altered gene expression profile of glioma cells with respect to mRNA, lncRNA and miRNA. Furthermore, our results showed that TMZ-induced HMGB1 increased the formation of GSCs and when HMGB1 was downregulated, TMZ-mediated GSCs formation was attenuated. Finally, we showed that the effect of HMGB1 on glioma cells was mediated by TLR2, which activated Wnt/β-catenin signaling to promote GSCs. Mechanistically, we found that HMGB1 upregulated NEAT1, which was responsible for Wnt/β-catenin activation. In conclusion, TMZ treatment upregulates HMGB1, which promotes the formation of GSCs via the TLR2/NEAT1/Wnt pathway. Blocking HMGB1-mediated GSCs formation could serve as a potential therapeutic target for preventing TMZ resistance in GBM patients.
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http://dx.doi.org/10.3389/fcell.2021.620883DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7891666PMC
February 2021

The association between dietary fatty acid intake and the risk of developing preeclampsia: a matched case-control study.

Sci Rep 2021 Feb 18;11(1):4048. Epub 2021 Feb 18.

Department of Epidemiology, School of Medicine, Jinan University, No.601 Huangpu Road West, Guangzhou, 510632, Guangdong, China.

The association between dietary fat intake during pregnancy and the risk of developing preeclampsia has been examined in many epidemiological studies, but the results remain inconsistent. The aim of this study was to clarify this association in pregnant Chinese women. After conducting 1:1 matching, 440 pairs consisting of pregnant women with preeclampsia and hospital-based, healthy pregnant women matched by gestational week (± 1 week) and age (± 3 years) were recruited. A 79-item semi-quantitative food frequency questionnaire administered during face-to-face interviews was used to estimate the participants' dietary intake of fatty acids. We found that the intakes of arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were inversely associated with the risk of developing preeclampsia. Compared with the lowest quartile intake, the multivariate-adjusted odds ratios (95% confidence interval) of the highest quartile intake were 0.42 (0.26-0.68, p-trend < 0.001) for EPA, 0.52 (0.3-0.83, p-trend = 0.005) for DHA, and 0.41 (0.19-0.88, p-trend = 0.007) for AA. However, we did not observe any significant associations between the intake of total fatty acids, saturated fatty acids, and mono-unsaturated fatty acids and the risk of developing preeclampsia. Our results showed that the dietary intake of long-chain polyunsaturated fatty acids (i.e., EPA, DHA, and AA) may protect pregnant Chinese women against the development of preeclampsia.
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http://dx.doi.org/10.1038/s41598-021-83674-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7893000PMC
February 2021

Altered intrinsic brain activity in patients with hepatic encephalopathy.

J Neurosci Res 2021 May 13;99(5):1337-1353. Epub 2021 Feb 13.

Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, P.R. China.

Neuropsychiatric deficits are common in patients with liver cirrhosis (LC), especially in those with hepatic encephalopathy (HE). Previous studies reveal abnormalities in brain activity underlying the neuropsychiatric deficits in LC patients; however, the results are inconsistent. We conducted a meta-analysis of resting-state functional magnetic resonance imaging studies using anisotropic effect-size signed differential mapping software on LC patients to characterize the most consistent regional activity alterations, and to evaluate the potential effect of liver transplantation (LT) on brain function. Meta-regression analyses were performed to explore the relationship between brain alterations and clinical variables. Compared with healthy controls, the typical patterns of increased regional activity in the fronto-striato-cerebellar network and decreased activity in the visuo-sensorimotor network and cingulate gyrus were identified in LC patients, which remained significant in the subgroup meta-analyses of minimal HE (MHE) and overt HE (OHE) patients. Functional deficits in the default mode network (DMN) were found in OHE patients compared with MHE patients. Ammonia level positively correlated with brain activity in the right middle temporal gyrus, and the completion time of number connection test A negatively correlated with brain activity in the left anterior cingulate gyrus. In addition, patients showed increased activity in the visuo-sensorimotor network and precuneus after LT. Our study suggests that alterations in the fronto-striato-cerebellar and visuo-sensorimotor networks may be the potential pathophysiological mechanisms underlying HE, and deficits in the DMN may indicate the progression of HE. LT may improve brain function in the visuo-sensorimotor network. This study has registered in the PROSPERO (CRD42020212758).
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http://dx.doi.org/10.1002/jnr.24788DOI Listing
May 2021

Gray Matter Atrophy in the Cortico-Striatal-Thalamic Network and Sensorimotor Network in Relapsing-Remitting and Primary Progressive Multiple Sclerosis.

Neuropsychol Rev 2021 Feb 13. Epub 2021 Feb 13.

Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, 610041, China.

Gray matter atrophy in multiple sclerosis (MS) is thought to be associated with disability and cognitive impairment, but previous studies have sometimes had discordant results, and the atrophy patterns of relapsing-remitting multiple sclerosis (RRMS) and primary progressive multiple sclerosis (PPMS) remain to be clarified. We conducted a meta-analysis using anisotropic effect-size-based algorithms (AES-SDM) to identify consistent findings from whole-brain voxel-based morphometry (VBM) studies of gray matter volume (GMV) in 924 RRMS patients and 204 PPMS patients. This study is registered with PROSPERO (number CRD42019121319). Compared with healthy controls, RRMS and PPMS patients showed gray matter atrophy in the cortico-striatal-thalamic network, sensorimotor network, and bilateral insula. RRMS patients had a larger GMV in the left insula, cerebellum, right precentral gyrus, and bilateral putamen as well as a smaller GMV in the bilateral cingulate, caudate nucleus, right thalamus, superior temporal gyrus and left postcentral gyrus than PPMS patients. The disease duration, Expanded Disability Status Scale score, Paced Auditory Serial Addition Test z-score, and T2-weighted lesion load were associated with specific gray matter regions in RRMS or PPMS. Alterations in the cortico-striatal-thalamic networks, sensorimotor network, and insula may be involved in the common pathogenesis of RRMS and PPMS. The deficits in the cingulate gyrus and caudate nucleus are more apparent in RRMS than in PPMS. The more severe cerebellum atrophy in PPMS may be a brain feature associated with its neurological manifestations. These imaging biomarkers provide morphological evidence for the pathophysiology of MS and should be verified in future research.
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http://dx.doi.org/10.1007/s11065-021-09479-3DOI Listing
February 2021

Microsurgery vs. Gamma Knife Radiosurgery for the Treatment of Brainstem Cavernous Malformations: A Systematic Review and Meta-Analysis.

Front Neurol 2021 26;12:600461. Epub 2021 Jan 26.

Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China.

Brainstem cavernous malformations (BSCMs) are a subset of cerebral cavernous malformations with precarious locations and potentially devastating clinical courses. The effects and outcomes of treating BSCMs by microsurgery or gamma knife radiosurgery (GKRS) vary across studies. We searched the Medline, Web of Science, The Cochrane Library, PubMed, and China Biology Medicine disc databases for original articles published in peer-reviewed journals of cohort studies reporting on 20 or more patients of any age with BSCMs with at least 80% completeness of follow-up. We included 43 cohorts involving 2,492 patients. Both microsurgery (RR = 0.04, 95% CI 0.01-0.16, < 0.01) and GKRS (RR = 0.11, 95% CI 0.08-0.16, < 0.01) demonstrated great efficacy in reducing the rehemorrhage rate after treatment for BSCMs. The incidence rates of composite outcomes were 19.8 (95% CI 16.8-22.8) and 15.7 (95% CI 11.7-19.6) after neurosurgery and radiosurgery, respectively. In addition, we found statistically significant differences in the median numbers of patients between neurosurgical and radiosurgical cohorts in terms of symptomatic intracranial hemorrhage (ICH; neurosurgical cohorts: median 0, range 0-33; radiosurgical cohorts: median 4, range 1-14; < 0.05) and persistent focal neurological deficit (FND; neurosurgical cohorts: median 5, range 0-140; radiosurgical cohorts: median 1, range 0-3; < 0.05). The reported effects of treating BSCMs by microsurgery or GKRS are favorable for reducing recurrent hemorrhage from BSCMs. Patients in the neurosurgery cohort had a lower incidence of symptomatic ICH, while patients in the radiosurgical cohort had a lower incidence of persistent FND.
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http://dx.doi.org/10.3389/fneur.2021.600461DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870787PMC
January 2021

Association of daytime napping in relation to risk of diabetes: evidence from a prospective study in Zhejiang, China.

Nutr Metab (Lond) 2021 Feb 8;18(1):18. Epub 2021 Feb 8.

Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.

Background: Diabetes was a major risk factor for numerous chronic diseases. However, the associations between daytime napping and diabetes in the existing literature is still inconsistent.

Methods: The analysis included 53,916 participants aged 30-79 years of the China Kadoorie Biobank prospective study from Tongxiang. Incident diabetes were identified through linkage with incident diabetes surveillance systems, health insurance system, and death registries. Cox regressions were used to estimate the associations of daytime napping with diabetes.

Results: 5.11% of participants reported habitual daytime napping. During 488,233 person-years (median 9.4 years) of follow-up, 3333 incident diabetes, including 1249 males and 2084 females, were documented. After adjusting for socio-demographic status, behavioral lifestyle, BMI, waist circumference and snoring, as comparison with those without daytime napping, the hazard ratios for risk of diabetes were 1.39 (95% CI 1.21-1.59). The corresponding figures for males and females were 1.45 (95% CI 1.20-1.74) and 1.30 (95% CI 1.05-1.59), respectively. The corresponding figures for postmenopausal and premenopausal females were 1.41 (95% CI 1.08-1.80) and 1.13 (95% CI 0.78-1.59), respectively.

Conclusions: Habitual daytime napping is positively associated with risk of diabetes in adults, except premenopausal females.
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http://dx.doi.org/10.1186/s12986-021-00545-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7869458PMC
February 2021

[Diagnosis and treatment of 11 cases of subperiosteal orbital abscess caused by acute sinusitis].

Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2021 Feb;35(2):125-130

Department of Otorhinolaryngology Head and Neck Surgery,Yantai Yuhuangding Hospital,Qingdao University,Yantai,264000,China.

The aim of this study is to explore the diagnosis, clinical manifestations and surgical treatment experience of acute sinusitis complicated with orbital subperiosteal abscess. The clinical data of 11 patients with acute sinusitis complicated by orbital subperiosteal abscess from 1 year and 8 months to 50 years were retrospectively analyzed, including clinical manifestations, imaging manifestations, bacteriological examinations, surgical methods and therapeutic effects. All patients were given antibacterial drugs, glucocorticoids, and surgery. All 11 patients had unilateral lesions. The imaging examinations all supported the appearance of orbital subperiosteal abscess. Nine patients underwent nasal endoscopic sinus opening+SPOA incision and drainage, 2 patients underwent nasal endoscopic sinus opening+ultrasound guided abscess puncture. Eyelid swelling and exophthalmia of all patients were alleviated when discharged. Ten of the 11 patients had no visual acuity change, and one patient had light perception only when she came to the hospital and recovered to 0.05 when discharged, there was no change in visual acuity after 3 months follow-up. The bacterial cultures of nasal secretion or pus were positive in 7 cases, the main pathogenic bacteria were Staphylococcus aureus(3 cases, includes one case of MRSA), Streptococcus anginosus(2 cases), and Streptococcus intermedius(2 cases). Rhinogenous orbital subperiosteal abscess has a rapid onset and progresses quickly. Once an abscess is formed, patients with poor conservative treatment should choose surgical treatment as soon as possible. The most common surgical method is nasal endoscopic sinus opening+SPOA incision and drainage. If the abscess is located above or above the eyeball, puncture or incision and drainage should be combined with ultrasound guidance.
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http://dx.doi.org/10.13201/j.issn.2096-7993.2021.02.008DOI Listing
February 2021

Amblyopia and Refractive Status in Congenital Ptosis: The Effect and Timing of Surgical Correction.

Ann Plast Surg 2021 Feb 1. Epub 2021 Feb 1.

From the Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, the People's Republic of China.

Purpose: The aim of this study was to explore the effect of congenital ptosis on the visual function of patients and observe the improvement in visual function after the correction of ptosis at different surgical times.

Methods: We performed a retrospective study of 265 patients (346 eyes) with congenital ptosis at the same hospital. Each patient underwent an ophthalmic examination, including optometry and measurement of the affected palpebral fissure height and upper eyelid margin reflex distance. Preoperative clinical and morphologic data were compared with postoperative data.

Results: The refractive error of the patient population was significantly different from that of the general population (P < 0.01). The rates of strabismus and amblyopia were 12.45% and 36.98%, respectively, in the ptosis patients, both of which are higher than the rates in the general population (P < 0.01), especially for unilaterally affected patients and patients with the optical axis covered. The refractive error of patients younger than 5 years was improved postoperatively (P < 0.05). The number of cases of amblyopia and strabismus was reduced, as was the percentage of cases of with-the-rule astigmatism (P < 0.05).

Conclusion: Congenital ptosis can result in refractive error, strabismus, and amblyopia, which could seriously impair the visual function of patients. The impairment is more pronounced in unilaterally affected patients. Surgery is conducive to the recovery of visual function, especially in patients younger than 5 years. Satisfactory curative effects can be obtained before the age of 3 years; thus, unilaterally affected patients, severely affected patients, and patients with impaired visual function should undergo surgery as soon as possible.
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http://dx.doi.org/10.1097/SAP.0000000000002677DOI Listing
February 2021

Tunable strongly coupled superconductivity in magic-angle twisted trilayer graphene.

Nature 2021 02 1;590(7845):249-255. Epub 2021 Feb 1.

Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.

Moiré superlattices have recently emerged as a platform upon which correlated physics and superconductivity can be studied with unprecedented tunability. Although correlated effects have been observed in several other moiré systems, magic-angle twisted bilayer graphene remains the only one in which robust superconductivity has been reproducibly measured. Here we realize a moiré superconductor in magic-angle twisted trilayer graphene (MATTG), which has better tunability of its electronic structure and superconducting properties than magic-angle twisted bilayer graphene. Measurements of the Hall effect and quantum oscillations as a function of density and electric field enable us to determine the tunable phase boundaries of the system in the normal metallic state. Zero-magnetic-field resistivity measurements reveal that the existence of superconductivity is intimately connected to the broken-symmetry phase that emerges from two carriers per moiré unit cell. We find that the superconducting phase is suppressed and bounded at the Van Hove singularities that partially surround the broken-symmetry phase, which is difficult to reconcile with weak-coupling Bardeen-Cooper-Schrieffer theory. Moreover, the extensive in situ tunability of our system allows us to reach the ultrastrong-coupling regime, characterized by a Ginzburg-Landau coherence length that reaches the average inter-particle distance, and very large T/T values, in excess of 0.1 (where T and T are the Berezinskii-Kosterlitz-Thouless transition and Fermi temperatures, respectively). These observations suggest that MATTG can be electrically tuned close to the crossover to a two-dimensional Bose-Einstein condensate. Our results establish a family of tunable moiré superconductors that have the potential to revolutionize our fundamental understanding of and the applications for strongly coupled superconductivity.
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http://dx.doi.org/10.1038/s41586-021-03192-0DOI Listing
February 2021

Study of the Physical Environment of Waiting Areas and Its Effects on Patient Satisfaction, Experience, Perceived Waiting Time, and Behavior in China.

HERD 2021 Jan 29:1937586721989058. Epub 2021 Jan 29.

Department of Architecture, College of Architecture and Art, Hefei University of Technology, China.

Objectives: This study examines the physical environment in the outpatient waiting area and its effects on overall satisfaction, experience, perceived waiting time, and behavior.

Background: Waiting can be a frustrating experience for patients. Previous studies on waiting areas in hospitals have been rooted mainly in the Western cultural context, and research focusing on the impact of the physical environment on the waiting experience with the denser patient concentration in China is important.

Methods: Physical environment measurements, observations, and questionnaire surveys were employed.

Results: The actual lighting intensity and sound level did not meet the national standards. Sound level and satisfaction with the size of the waiting area, signage system, and visual art on the wall were significant predictors ( = .463, = .000) for overall satisfaction. Experiences related to the size of the waiting area, seating, signage system, and restrooms were significant predictors ( = .373, = .000) of overall waiting experience. The experience related to the acoustic environment (β = -.184, = .006) had a significant relationship with perceived waiting time. The increase in participants' behaviors of looking out of a window and the decrease in looking at other people, looking around, dozing, and looking at a wall might result from a substantial increase in lighting and the availability of a nature view from the window.

Conclusions: The effect of the physical setting of waiting areas may positively impact patient satisfaction, waiting experience, perceived waiting time, and behavior, which has implications for patient-centered design.
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http://dx.doi.org/10.1177/1937586721989058DOI Listing
January 2021

Ginsenoside Rb1 Facilitates Browning by Repressing Wnt/β-Catenin Signaling in 3T3-L1 Adipocytes.

Med Sci Monit 2021 Jan 27;27:e928619. Epub 2021 Jan 27.

Department of Anatomy and Histology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (mainland).

BACKGROUND The discovery of browning in white adipose tissue has provided new ideas for treating obesity. Many studies have reported that ginsenoside Rb1 (G-Rb1) has activity against diabetes, inflammation, and obesity, but further investigation is needed on the effect and mechanism of G-Rb1 on browning. MATERIAL AND METHODS We treated 3T3-L1 adipocytes with 0-200 μM G-Rb1, and 0.5 μM Compound 3f and 30 μM SKL2001 were used to activate Wnt/b-catenin signaling. Adipocyte activity was evaluated by Cell Counting Kit-8. Oil Red O staining was used to detect the lipid droplets. Quantitative real-time polymerase chain reaction was used to measure the expression of Cd-137, Cited-1, Txb-1, Prdm-16, and Ucp-1 mRNA. Western blotting was used to measure the expression of Ucp-1, pGSK-3ß (Ser 9), GSK- 3ß, and ß-catenin proteins. The expression of Ucp-1 was also detected with immunofluorescence. RESULTS Adipocyte activity was not affected by 0-100 μM G-Rb1. However, G-Rb1 dose-dependently reduced the accumulation of lipid droplets; increased the expression of Cd-137, Cited-1, Txb-1, Prdm-16, and Ucp-1 mRNA; and increased the expression of Ucp-1, pGSK-3ß (Ser 9), GSK-3ß, and ß-catenin proteins. The accumulation of lipid droplets and the expression of Ucp-1 protein decreased as b-catenin increased. CONCLUSIONS G-Rb1 at various concentrations (0-100 μM) promoted the browning of adipocytes in a dose-dependent manner. Further, we confirmed that activation of Wnt/ß-catenin signaling could inhibit browning. Therefore, the browning promoted by G-Rb1 may be associated with the inhibition of Wnt/ß-catenin signaling.
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http://dx.doi.org/10.12659/MSM.928619DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7849207PMC
January 2021

Respiratory tract infections in children with allergic asthma on allergen immunotherapy during influenza season.

Sci Rep 2021 Jan 22;11(1):2083. Epub 2021 Jan 22.

Pediatrics, Zibo Municipal Hospital, No. 139, Huangong Road, Zibo, 255400, Shandong Province, China.

To describle how respiratory tract infections (RTIs) that occurred in children with allergic asthma (AA) on allergen immunotherapy (AIT) during an influenza season. Data including clinical symptoms and treatment history of children (those with AA on AIT and their siblings under 14 years old), who suffered from RTIs during an influenza season (Dec 1st, 2019-Dec 31st, 2019), were collected (by face to face interview and medical records) and analyzed. Children on AIT were divided into 2 groups: stage 1 (dose increasing stage) and stage 2 (dose maintenance stage). Their siblings were enrolled as control. During the study period, 49 children with AA on AIT (33 patients in stage 1 and 16 patients in stage 2) as well as 49 children without AA ( their siblings ) were included. There were no significant differences in occurrences of RTIs among the three groups (p > 0.05). Compared with children in the other two groups, patients with RTIs in stage 2 had less duration of coughing and needed less medicine. Children on AIT with maintenance doses had fewer symptoms and recovered quickly when they were attacked by RTIs, which suggested that AIT with dose maintenance may enhance disease resistance of the body.
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http://dx.doi.org/10.1038/s41598-021-81558-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7822879PMC
January 2021

Long-Distance Free-Space Measurement-Device-Independent Quantum Key Distribution.

Phys Rev Lett 2020 Dec;125(26):260503

Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China.

Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fiber-based implementations aimed at longer distance, higher key rates, and network verification have been rapidly developed. However, owing to the effect of atmospheric turbulence, MDI-QKD over a free-space channel remains experimentally challenging. Herein, by developing a robust adaptive optics system, high-precision time synchronization and frequency locking between independent photon sources located far apart, we realized the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step toward satellite-based MDI-QKD. Moreover, the technology developed herein opens the way to quantum experiments in free space involving long-distance interference of independent single photons.
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http://dx.doi.org/10.1103/PhysRevLett.125.260503DOI Listing
December 2020

Molecular Characteristics of N1-Methyladenosine Regulators and Their Correlation with Overall Cancer Survival.

DNA Cell Biol 2021 Mar 8;40(3):513-522. Epub 2021 Jan 8.

Department of Gynaecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, P.R. China.

N1-methyladenosine (m1A) is a prevalent RNA modification widely affecting RNA structural stability, folding, and interactions with proteins. Recently, there have been increasing reports on the roles of m1A regulators in tumors. However, their mechanisms and clinical relevance remain unclear. This study systematically evaluates the epigenetic characteristics and clinical relevance of m1A regulators using bioinformatic methods. Our results show widespread gene expression changes for m1A regulators, which are related to the activation and inhibition of carcinogenic pathways and overall patient survival. Collectively, this investigation provides new insights into assessing tumor prognosis and targeted therapy.
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http://dx.doi.org/10.1089/dna.2020.6214DOI Listing
March 2021

An integrated space-to-ground quantum communication network over 4,600 kilometres.

Nature 2021 01 6;589(7841):214-219. Epub 2021 Jan 6.

Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Anhui, China.

Quantum key distribution (QKD) has the potential to enable secure communication and information transfer. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres; this distance was later extended to the 100-kilometre scale with decoy-state QKD and more recently to the 500-kilometre scale with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area. Quantum repeaters could in principle provide a viable option for such a global network, but they cannot be deployed using current technology. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.
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http://dx.doi.org/10.1038/s41586-020-03093-8DOI Listing
January 2021

Age-related changes of standardized uptake values in the blood pool and liver: a decade-long retrospective study of the outcomes of 2,526 subjects.

Quant Imaging Med Surg 2021 Jan;11(1):95-106

Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China.

Background: Background activity on fluorine-18-fluorodeoxyglucose (F-FDG) positron emission tomography/computed tomography (PET/CT) is often used as a reference to assess a patient's response to tumor treatment. To produce a suitable background activity reference, we examined the variations in standardized uptake values (SUVs) in the blood pool and liver of a large multi-aged population.

Methods: A total of 2,526 subjects underwent F-FDG PET/CT examinations and were divided into 12 age groups. Pearson's partial correlation and multivariate regression analyses were performed to assess the associations between individual factors and SUVs of the blood pool and liver and to identify the factor that most influenced the SUVs. The mean SUVs across the age groups were also determined.

Results: Positive correlations were found between individual factors and SUVs. Age appeared to be the most important predictor of SUVs and was significantly associated with the blood pool SUV (ß=0.466, P=0.000), blood pool SUV (ß=0.393, P=0.000), liver SUV (ß=0.347, P=0.000), and liver SUV (ß=0.354, P=0.000). Blood pool and liver SUVs rose rapidly until the age of 20 and then showed a slow upward trend without reaching a plateau.

Conclusions: Age is an important factor that influences variations in the blood pool and liver SUVs. Our study clarified this understanding of age-related variations in SUVs and provided a normal range of blood pool and liver SUVs that may aid clinicians in evaluating tumors with greater accuracy.
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http://dx.doi.org/10.21037/qims-20-35DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719952PMC
January 2021

Probucol decreases homocysteine-stimulated CRP production in rat aortic smooth muscle cells via regulating HO-1/NADPH oxidase/ROS/p38 pathway.

Acta Biochim Biophys Sin (Shanghai) 2021 Feb;53(2):212-219

Department of Clinical Pharmacy, Zibo Central Hospital, Binzhou Medical University, Zibo 255000, China.

The elevated homocysteine level is an independent risk factor for atherosclerosis, which is characterized as a chronic inflammatory disease associated with oxidative stress. We have confirmed that homocysteine can stimulate the production of C-reactive protein (CRP) in rat aortic smooth muscle cells (RASMCs). In the present study, we investigated the role of probucol in homocysteine-induced CRP expression in cultured RASMCs and high-methionine-diet-induced hyperhomocysteinemic rats. The results showed that probucol decreased homocysteine-induced CRP mRNA and protein expression in RASMCs in a concentration-dependent manner. In addition, the animal experiment showed that probucol not only inhibited CRP expression in the vessel wall but also reduced the circulating CRP level in hyperhomocysteinemic rats. Further investigations revealed that probucol markedly increased heme oxygenase-1 activity, suppressed nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, diminished superoxide anion generation, and decreased p38 phosphorylation in RASMCs and hyperhomocysteinemic rat aorta. These data demonstrate that probucol can inhibit homocysteine-induced CRP generation by interfering with the NADPH oxidase/p38 signal pathway in RASMCs, which will provide new evidence for the anti-inflammatory and anti-atherosclerotic effects of probucol.
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http://dx.doi.org/10.1093/abbs/gmaa163DOI Listing
February 2021

Single-mode fiber coupling with a M-SPGD algorithm for long-range quantum communications.

Opt Express 2020 Nov;28(24):36600-36610

Satellite-based quantum communication is a promising approach for realizing global-scale quantum networks. For free-space quantum channel, single-mode fiber coupling is particularly important for improving the signal-to-noise ratio of daylight quantum key distribution (QKD) and compatibility with standard fiber-based QKD. However, achieving a highly efficient and stable single-mode coupling efficiency under strong atmospheric turbulence remains experimentally challenging. Here, we develop a single-mode receiver with an adaptive optics (AO) system based on a modal version of the stochastic parallel gradient descent (M-SPGD) algorithm and test its performance over an 8 km urban terrestrial free-space channel. Under strong atmospheric turbulence, the M-SPGD AO system obtains an improvement of about 3.7 dB in the single-mode fiber coupling efficiency and a significant suppression of fluctuation, which can find its applications in free-space long-range quantum communications.
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http://dx.doi.org/10.1364/OE.411939DOI Listing
November 2020

Development of a 443 nm diode laser-based differential photoacoustic spectrometer for simultaneous measurements of aerosol absorption and NO.

Photoacoustics 2021 Mar 9;21:100229. Epub 2020 Dec 9.

School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230031, China.

Measurement of ambient aerosol and nitrogen dioxide (NO) is important as they are major pollutants from the burning of fossil fuel and biomass. In the present work, a differential photoacoustic spectrometer (D-PAS) was developed for simultaneous, online measurements of aerosol optical absorption and NO concentration. A novel photoacoustic resonator was designed and employed in the D-PAS for controlling a large flow rate, improving response time, and keeping the flow noise at a low level. The detection limits of 1.0 Mm and 0.87 ppb for aerosol absorption and NO concentration measurements were achieved with a lock-in amplifier time constant of 1 s. The D-PAS accuracy was demonstrated by performing a long-time, continuous measurement of aerosol, and NO in ambient air. The measured results of NO are consistent with the NOx analyzer and environmental monitoring station results.
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http://dx.doi.org/10.1016/j.pacs.2020.100229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7749428PMC
March 2021

Spin-filter induced large magnetoresistance in 2D van der Waals magnetic tunnel junctions.

Nanoscale 2021 Jan 23;13(2):862-868. Epub 2020 Dec 23.

Fert Beijing Research Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering & Beijing Advanced Innovation Center for Big Data and Brain Computing, Beihang University, Beijing 100191, China.

Two-dimensional (2D) van der Waals (vdW) heterostructures, known as layer-by-layer stacked 2D materials in a precisely chosen sequence, have received more and more attention in spintronics for their ultra-clean interface, unique electronic properties and 2D ferromagnetism. Motivated by the recent synthesis of monolayer 1T-VSe2 with ferromagnetic ordering and a high Curie temperature above room temperature, we investigate the bias-voltage driven spin transport properties of 2D magnetic tunnel junctions (MTJs) based on VSe2 utilizing density functional theory combined with the nonequilibrium Green's function method. In the device 1T-MoSe2/1T-VSe2/2H-WSe2/1T-VSe2/1T-MoSe2, the tunneling magneto-resistance (TMR) is incredibly satisfactory up to 5600%. Based on the analysis of evanescent states, this large TMR is attributed to the spin filter effect at the interface between 1T-VSe2 and 2H-WSe2, which overcomes the low spin polarization of 1T-VSe2. Furthermore, by inserting 2H-MoSe2, the spin filter effect is enhanced with decreasing current and the TMR is drastically improved to 1.7 × 10%. This work highlights the feasibility of 2D vdW heterostructures for ultra-low power spintronic applications by electronic structural engineering.
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http://dx.doi.org/10.1039/d0nr07290gDOI Listing
January 2021