Publications by authors named "He Ma"

187 Publications

Robust Tracking Control of the Euler-Lagrange System Based on Barrier Lyapunov Function and Self-Structuring Neural Networks.

Comput Intell Neurosci 2021 12;2021:1277349. Epub 2021 Oct 12.

State Key Laboratory of Material Processing and Die and Mould Technology and School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

This article studies the robust tracking control problems of Euler-Lagrange (EL) systems with uncertainties. To enhance the robustness of the control systems, an asymmetric tan-type barrier Lyapunov function (ATBLF) is used to dynamic constraint position tracking errors. To deal with the problems of the system uncertainties, the self-structuring neural network (SSNN) is developed to estimate the unknown dynamics model and avoid the calculation burden. The robust compensator is designed to estimate and compensate neural network (NN) approximation errors and unknown disturbances. In addition, a relative threshold event-triggered strategy is introduced, which greatly saves communication resources. Under the proposed robust control scheme, tracking behavior can be implemented with disturbance and unknown dynamics of the EL systems. All signals in the closed-loop system are proved to be bounded by stability analysis, and the tracking error can converge to the neighborhood near the origin. The numerical simulation results show the effectiveness and the validity of the proposed robust control scheme.
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http://dx.doi.org/10.1155/2021/1277349DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8526255PMC
October 2021

Expressions of melanopsins in telencephalon imply their function in synchronizing semilunar spawning rhythm in the mudskipper Boleophthalmus pectinirostris.

Gen Comp Endocrinol 2021 Oct 13;315:113926. Epub 2021 Oct 13.

State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, Xiamen University, Xiamen 361102, China. Electronic address:

The mudskipper Boleophthalmus pectinirostris inhabits intertidal mudflats, exhibiting semilunar reproductive rhythms. To investigate whether melanopsin is possibly involved in the synchronization of the semilunar spawning rhythm in the female mudskipper, we first cloned all four melanopsin subtypes (opn4m1, opn4m3, opn4x1, opn4x2) in B. pectinirostris. Results from RTq-PCR showed that significantly higher transcription levels of all four melanopsin subtypes were observed in the eyes rather than other tissues. In brain, all four melanopsin subtypes were also detectable in different regions, including the telencephalon, in which the expression of melanopsin has not been reported in other teleosts. The transcription levels of opn4m3 and opn4x1 in the telencephalon exhibited a daily fluctuation pattern. When females entered the spawning season, opn4m1 and opn4x1 transcript levels increased significantly in the telencephalon. During the spawning season, the transcript levels of opn4m3 and opn4x1 in the telencephalon appeared to have a cyclic pattern associated with semilunar periodicity, exhibiting two cycles with a peak around the first or the last lunar quarters. Results from ISH showed that, opn4x1 mRNA was localized in the medial of dorsal telencephalic area, dorsal nucleus of ventral telencephalic area (Vd), ventral nucleus of ventral telencephalic area (Vv), anterior part of parvocellular preoptic nucleus, magnocellular part of the magnocellular preoptic nucleus (PMmc), habenular and ventral zone of hypothalamus. Intriguingly, gnrh3 mRNA was also located in Vd, Vv and PMmc. Taken together, our results suggested that melanopsins, e.g. opn4x1, expressed in the telencephalon might mediate semilunar spawning activity in the female mudskipper.
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http://dx.doi.org/10.1016/j.ygcen.2021.113926DOI Listing
October 2021

Graphene-Based Nanoelectromechanical Periodic Array with Tunable Frequency.

Nano Lett 2021 Oct 6;21(20):8571-8578. Epub 2021 Oct 6.

CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, Anhui 230026, China.

Phononic crystals (PnCs) have attracted much attention due to their great potential for dissipation engineering and propagation manipulation of phonons. Notably, the excellent electrical and mechanical properties of graphene make it a promising material for nanoelectromechanical resonators. Transferring a graphene flake to a prepatterned periodic mechanical structure enables the realization of a PnC with on-chip scale. Here, we demonstrate a nanoelectromechanical periodic array by anchoring a graphene membrane to a 9 × 9 array of standing nanopillars. The device exhibits a quasi-continuous frequency spectrum with resonance modes distributed from ∼120 MHz to ∼980 MHz. Moreover, the resonant frequencies of these modes can be electrically tuned by varying the voltage applied to the gate electrode sitting underneath. Simulations suggest that the observed band-like spectrum provides an experimental evidence for PnC formation. Our architecture has large fabrication flexibility, offering a promising platform for investigations on PnCs with electrical accessibility and tunability.
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http://dx.doi.org/10.1021/acs.nanolett.1c01866DOI Listing
October 2021

Treatment of spinal tuberculosis in rabbits using bovine serum albumin nanoparticles loaded with isoniazid and rifampicin.

Neurol Res 2021 Sep 28:1-7. Epub 2021 Sep 28.

Department of Orthopedics, General Hospital of Ningxia Medical University, Yinchuan, China.

Objective: To evaluate the clinical efficacy of bovine serum albumin nanoparticles loaded with isoniazid and rifampicin (INH-RFP-BSA-NPs) in the treatment of spinal tuberculosis in rabbits.

Methods: 35 spinal tuberculosis rabbit models were grouped into three groups, including 14 in group A and group B respectively and 7 in group C.All rabbits in group A were treated by INH-RFP-BSA-NPs's injection and in group B were treated with classic dosage form of INH and RFP, while in group C normal saline was given as the blank control. After intervention, the body weighing and CT scan, as well as concentration's measurement of INH and RFP in blood and tissues, were performed in all rabbits at the time of the 6thweek and 12th week, respectively.

Results: In group A, rabbits' weight increased by 0.44 kg and 0.27 kg within 6 weeks and 12 weeks' treatment respectively. The bactericidal concentrations of 1.64 µg•g for INH and 21.36 µg•g for RFP were measured in focus vertebral body 6 weeks post-injection and six weeks later the concentrations of INH and RFP in vertebral body still maintained at the level of 1.96 µg•g and 22.35 µg•grespectively. After 12 weeks therapy, CT-scanned showed all the necrotic tissue was replaced by normal bone tissue. In group B, all rabbits had no significant increment of body weight and 4 rabbits had paralysis of hind leg. The concentrations of INH and RFP in vertebral body and focus were much lower than group A. CT-scanned showed the focus vertebral body was only partially repaired after 12 weeks' therapy.

Conclusion: The INH-RFP-BSA-NPs has the characteristics of sustained release in vivo and target biodistribution in focus vertebral body. Its therapeutic effect in rabbit spinal tuberculosis is much better than common INH and RFP.
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http://dx.doi.org/10.1080/01616412.2021.1979749DOI Listing
September 2021

First-Principles Predictions of Out-of-Plane Group IV and V Dimers as High-Symmetry, High-Spin Defects in Hexagonal Boron Nitride.

ACS Appl Mater Interfaces 2021 Sep 20;13(38):45768-45777. Epub 2021 Sep 20.

Department of Energy Systems Research and Department of Physics, Ajou University, Suwon, Gyeonggi 16499, Korea.

Hexagonal boron nitride (h-BN) has been recently found to host a variety of quantum point defects, which are promising candidates as single-photon sources for solid-state quantum nanophotonic applications. Most recently, optically addressable spin qubits in h-BN have been the focus of intensive research due to their unique potential in quantum computation, communication, and sensing. However, the number of high-symmetry, high-spin defects that are desirable for developing spin qubits in h-BN is highly limited. Here, we combine density functional theory (DFT) and quantum embedding theories to show that out-of-plane XY dimer defects (X, Y = C, N, P, and Si) form a new class of stable C spin-triplet defects in h-BN. We find that the dimer defects have a robust A ground state and E excited state, both of which are isolated from the h-BN bulk states. We show that E and A shelving states exist and they are positioned between the E and A states for all the dimer defects considered in this study. To support future experimental identification of the XY dimer defects, we provide extensive characterization of the defects in terms of their spin and optical properties. We predict that the zero-phonon line of the spin-triplet XY defects lies in the visible range (800 nm to 500 nm). We compute the zero-field splitting of the dimers' spin to range from 1.79 GHz (SiP) to 29.5 GHz (CN). Our results broaden the scope of high-spin defect candidates that would be useful for the development of spin-based solid-state quantum technologies in two-dimensional hexagonal boron nitride.
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http://dx.doi.org/10.1021/acsami.1c16988DOI Listing
September 2021

Reversing Multidrug Resistance by Inducing Mitochondrial Dysfunction for Enhanced Chemo-Photodynamic Therapy in Tumor.

ACS Appl Mater Interfaces 2021 Sep 17;13(38):45259-45268. Epub 2021 Sep 17.

State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, Hi-tech Zone, Dalian 116024, P.R. China.

Efficiency of standard chemotherapy is dramatically hindered by intrinsic multidrug resistance (MDR). Recently, to amplify therapeutic efficacy, photodynamic therapy (PDT)-induced mitochondrial dysfunction by decorating targeting moieties on nanocarriers has obtained considerable attention. Nevertheless, low targeting efficiency, complex synthesis routes, and difficulty in releasing contents become the major obstacles in further clinical application. Herein, an ingenious liposomal-based nanomedicine ([email protected]) was fabricated by encapsulating a mitochondria-anchored photosensitizer (Cy-Br) and paclitaxel (PTX) for realizing enhanced cooperation therapy. At the cellular level, [email protected] could hurdle endosomal traps to localize and implement PDT in mitochondria. Intriguingly, the PDT-induced mitochondrial dysfunction led to intracellular ATP reduction, which triggered the downregulated P-glycoprotein transportation capacity and thus resulted in diminishing the efflux of chemotherapeutic agents and increasing drug uptake by drug-resistant cells. The prepared nanomedicine eminently accumulated in the tumor site and acquired enhanced therapeutic efficiency on PTX-resistant lung cancer cells, which possessed great potential in circumventing MDR tumors.
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http://dx.doi.org/10.1021/acsami.1c12725DOI Listing
September 2021

Deep Learning With Data Enhancement for the Differentiation of Solitary and Multiple Cerebral Glioblastoma, Lymphoma, and Tumefactive Demyelinating Lesion.

Front Oncol 2021 18;11:665891. Epub 2021 Aug 18.

Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Objectives: To explore the MRI-based differential diagnosis of deep learning with data enhancement for cerebral glioblastoma (GBM), primary central nervous system lymphoma (PCNSL), and tumefactive demyelinating lesion (TDL).

Materials And Methods: This retrospective study analyzed the MRI data of 261 patients with pathologically diagnosed solitary and multiple cerebral GBM (n = 97), PCNSL (n = 92), and TDL (n = 72). The 3D segmentation model was trained to capture the lesion. Different enhancement data were generated by changing the pixel ratio of the lesion and non-lesion areas. The 3D classification network was trained by using the enhancement data. The accuracy, sensitivity, specificity, and area under the curve (AUC) were used to assess the value of different enhancement data on the discrimination performance. These results were then compared with the neuroradiologists' diagnoses.

Results: The diagnostic performance fluctuated with the ratio of lesion to non-lesion area changed. The diagnostic performance was best when the ratio was 1.5. The AUCs of GBM, PCNSL, and TDL were 1.00 (95% confidence interval [CI]: 1.000-1.000), 0.96 (95% CI: 0.923-1.000), and 0.954 (95% CI: 0.904-1.000), respectively.

Conclusions: Deep learning with data enhancement is useful for the accurate identification of GBM, PCNSL, and TDL, and its diagnostic performance is better than that of the neuroradiologists.
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http://dx.doi.org/10.3389/fonc.2021.665891DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8416477PMC
August 2021

Complete structural characterization of single carbon nanotubes by Rayleigh scattering circular dichroism.

Nat Nanotechnol 2021 Oct 12;16(10):1073-1078. Epub 2021 Aug 12.

State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, China.

Non-invasive, high-throughput spectroscopic techniques can identify chiral indices (n,m) of carbon nanotubes down to the single-tube level. Yet, for complete characterization and to unlock full functionality, the handedness, the structural property associated with mirror symmetry breaking, also needs to be identified accurately and efficiently. So far, optical methods fail in the handedness characterization of single nanotubes because of the extremely weak chiroptical signals (roughly 10) compared with the excitation light. Here we demonstrate the complete structure identification of single nanotubes in terms of both chiral indices and handedness by Rayleigh scattering circular dichroism. Our method is based on the background-free feature of Rayleigh scattering collected at an oblique angle, which enhances the nanotube's chiroptical signal by three to four orders of magnitude compared with conventional absorption circular dichroism. We measured a total of 30 single-walled carbon nanotubes including both semiconducting and metallic nanotubes and found that their absolute chiroptical signals show a distinct structure dependence, which can be qualitatively understood through tight-binding calculations. Our strategy enables the exploration of handedness-related functionality of single nanotubes and provides a facile platform for chiral discrimination and chiral device exploration at the level of individual nanomaterials.
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http://dx.doi.org/10.1038/s41565-021-00953-wDOI Listing
October 2021

Breast Cancer Segmentation Methods: Current Status and Future Potentials.

Biomed Res Int 2021 20;2021:9962109. Epub 2021 Jul 20.

Radiology Department, Affiliated Hospital of Guizhou, Medical Hospital, China.

Early breast cancer detection is one of the most important issues that need to be addressed worldwide as it can help increase the survival rate of patients. Mammograms have been used to detect breast cancer in the early stages; if detected in the early stages, it can drastically reduce treatment costs. The detection of tumours in the breast depends on segmentation techniques. Segmentation plays a significant role in image analysis and includes detection, feature extraction, classification, and treatment. Segmentation helps physicians quantify the volume of tissue in the breast for treatment planning. In this work, we have grouped segmentation methods into three groups: classical segmentation that includes region-, threshold-, and edge-based segmentation; machine learning segmentation; and supervised and unsupervised and deep learning segmentation. The findings of our study revealed that region-based segmentation is frequently used for classical methods, and the most frequently used techniques are region growing. Further, a median filter is a robust tool for removing noise. Moreover, the MIAS database is frequently used in classical segmentation methods. Meanwhile, in machine learning segmentation, unsupervised machine learning methods are more frequently used, and U-Net is frequently used for mammogram image segmentation because it does not require many annotated images compared with other deep learning models. Furthermore, reviewed papers revealed that it is possible to train a deep learning model without performing any preprocessing or postprocessing and also showed that the U-Net model is frequently used for mammogram segmentation. The U-Net model is frequently used because it does not require many annotated images and also because of the presence of high-performance GPU computing, which makes it easy to train networks with more layers. Additionally, we identified mammograms and utilised widely used databases, wherein 3 and 28 are public and private databases, respectively.
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http://dx.doi.org/10.1155/2021/9962109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8321730PMC
September 2021

Flexible Photodriven Actuator Based on Gradient-Paraffin-Wax-Filled TiCT MXene Film for Bionic Robots.

ACS Nano 2021 Jul 9. Epub 2021 Jul 9.

Faculty of Science, Beijing University of Technology, Beijing 100124, China.

Due to their high flexibility and adaptability, bionic robots have great potential in applications such as healthcare, rescue, and surveillance. The flexible actuator is an essential component of the bionic robot and determines its performance. Even though much progress has been achieved in bionic robot research, there still exists a great challenge in preparing a flexible actuator with a large stroke, high sensitivity, fast response, low triggering power, and long lifetime. This study presents a flexible actuator based on a paraffin wax and TiCT MXene (PW-MX) film composite. Such a flexible actuator delivers an excellent actuation performance, including a large curvature change (2.2 × 10 m), high thermal sensitivity (4.6 m/°C), low triggering power of light (76 mW/cm), wavelength selectivity, fast response (0.38 s), and long lifetime (>20000 cycles). Due to the high thermal sensitivity and the strong infrared absorption of the PW-MX film, crawling motion of an inchworm robot based on PW-MX film can be triggered by infrared irradiation from the human finger. To mimic living organisms with bioluminescence, we prepared a PW-MX actuator with green fluorescence by doping PW-MX film with CdSe/ZnS quantum dots. The integration of luminescent function enables the PW-MX actuator to deliver information under light stimulation and to camouflage under a background of green foliage actively. With its merits of ease of fabrication and high actuation performance, the flexible PW-MX actuator is expected to lend itself to more applications in the future.
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http://dx.doi.org/10.1021/acsnano.1c03950DOI Listing
July 2021

Lesion segmentation in breast ultrasound images using the optimized marked watershed method.

Biomed Eng Online 2021 Jun 7;20(1):57. Epub 2021 Jun 7.

College of Medicine and Biological Information Engineering, Northeastern University, Shenyang, China.

Background: Breast cancer is one of the most serious diseases threatening women's health. Early screening based on ultrasound can help to detect and treat tumours in the early stage. However, due to the lack of radiologists with professional skills, ultrasound-based breast cancer screening has not been widely used in rural areas. Computer-aided diagnosis (CAD) technology can effectively alleviate this problem. Since breast ultrasound (BUS) images have low resolution and speckle noise, lesion segmentation, which is an important step in CAD systems, is challenging.

Results: Two datasets were used for evaluation. Dataset A comprises 500 BUS images from local hospitals, while dataset B comprises 205 open-source BUS images. The experimental results show that the proposed method outperformed its related classic segmentation methods and the state-of-the-art deep learning model RDAU-NET. Its accuracy (Acc), Dice similarity coefficient (DSC) and Jaccard index (JI) reached 96.25%, 78.4% and 65.34% on dataset A, and its Acc, DSC and sensitivity reached 97.96%, 86.25% and 88.79% on dataset B, respectively.

Conclusions: We proposed an adaptive morphological snake based on marked watershed (AMSMW) algorithm for BUS image segmentation. It was proven to be robust, efficient and effective. In addition, it was found to be more sensitive to malignant lesions than benign lesions.

Methods: The proposed method consists of two steps. In the first step, contrast limited adaptive histogram equalization (CLAHE) and a side window filter (SWF) are used to preprocess BUS images. Lesion contours can be effectively highlighted, and the influence of noise can be eliminated to a great extent. In the second step, we propose adaptive morphological snake (AMS). It can adjust the working parameters adaptively according to the size of the lesion. Its segmentation results are combined with those of the morphological method. Then, we determine the marked area and obtain candidate contours with a marked watershed (MW). Finally, the best lesion contour is chosen by the maximum average radial derivative (ARD).
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http://dx.doi.org/10.1186/s12938-021-00891-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8186073PMC
June 2021

Radiomics-Based Features for Prediction of Histological Subtypes in Central Lung Cancer.

Front Oncol 2021 29;11:658887. Epub 2021 Apr 29.

Department of Radiology, The First Hospital of China Medical University, Shenyang, China.

Objectives: To evaluate the effectiveness of radiomic features on classifying histological subtypes of central lung cancer in contrast-enhanced CT (CECT) images.

Materials And Methods: A total of 200 patients with radiologically defined central lung cancer were recruited. All patients underwent dual-phase chest CECT, and the histological subtypes (adenocarcinoma (ADC), squamous cell carcinoma (SCC), small cell lung cancer (SCLC)) were confirmed by histopathological samples. 107 features were used in five machine learning classifiers to perform the predictive analysis among three subtypes. Models were trained and validated in two conditions: using radiomic features alone, and combining clinical features with radiomic features. The performance of the classification models was evaluated by the area under the receiver operating characteristic curve (AUC).

Results: The highest AUCs in classifying ADC vs. SCC, ADC vs. SCLC, and SCC vs. SCLC were 0.879, 0.836, 0.783, respectively by using only radiomic features in a feedforward neural network.

Conclusion: Our study indicates that radiomic features based on the CECT images might be a promising tool for noninvasive prediction of histological subtypes in central lung cancer and the neural network classifier might be well-suited to this task.
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http://dx.doi.org/10.3389/fonc.2021.658887DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8117140PMC
April 2021

Systematic Chromatin Accessibility Analysis Based on Different Immunological Subtypes of Clear Cell Renal Cell Carcinoma.

Front Oncol 2021 16;11:575425. Epub 2021 Apr 16.

Department of Urology, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.

Background: Recent research of clear cell renal cell carcinoma (ccRCC) is focused on the tumor immune microenvironment (TIME). Chromatin accessibility is critical for regulation of gene expression. However, its role in different immunological subtypes of ccRCC based on immune cell infiltration has not been systematically studied.

Methods: Five hundred thirty patient data from The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma (TCGA-KIRC) were adopted to estimate immune cell infiltration. Twenty-four types of immune cells were evaluated with single-sample Gene Set Enrichment Analysis (ssGSEA). Patients were divided into two clusters based on immune cell infiltration. Systematic chromatin accessibility analysis was conducted based on the two clusters.

Results: We compared the relative expression of the immune gene signatures among 530 patients of TCGA-KIRC using ssGSEA. Overall survival (OS) analysis revealed 10 types of immune cells were significantly associated with prognosis. Patients were divided into two clusters based on 24 types of immune cell infiltration. Immune cell signals as well as PD-1/PD-L1 signal were higher in cluster 1. Among the two clusters, 2,400 differential peaks were found in TCGA-KIRC Transposase Accessible Chromatin with high-throughput sequencing (ATAC-seq) data. The distribution of differential peaks and prognosis-related immune cells in 23 chromosomes are essentially the same. There is no peak distribution downstream. The proportion of peaks upstream of the 5' transcription start site decreases, and both sides of binding regions of the TSS 0.1-1 kb becomes smaller. Enrichment analysis of GO and KEGG of these differential peaks showed that they are remarkably related to the immune regulation in tumor microenvironment. Known motifs and motifs were found by linking motif annotations to different peaks. Survival analysis of related motif transcription factors were prognostic. The GSEA enrichment analysis showed that high SP1 expression positively correlates with TGF-beta signaling and inflammatory response, while negatively correlates with TNF-alpha signaling NFKB. High KLF12 expression negatively correlates with interferon gamma response, IL2-STAT5 signaling, TNF-alpha signaling NFKB, IL6-JAK-STAT3 signaling.

Conclusion: The abnormality of chromatin accessibility may play an important regulatory role in ccRCC immunity.
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http://dx.doi.org/10.3389/fonc.2021.575425DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8085385PMC
April 2021

Quantum Embedding Theory for Strongly Correlated States in Materials.

J Chem Theory Comput 2021 Apr 19;17(4):2116-2125. Epub 2021 Mar 19.

Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.

Quantum embedding theories are promising approaches to investigate strongly correlated electronic states of active regions of large-scale molecular or condensed systems. Notable examples are spin defects in semiconductors and insulators. We present a detailed derivation of a quantum embedding theory recently introduced, which is based on the definition of effective Hamiltonians. The effect of the environment on a chosen active space is accounted for through screened Coulomb interactions evaluated using density functional theory. Importantly, the random phase approximation is not required, and the evaluation of virtual electronic orbitals is circumvented with algorithms previously developed in the context of calculations based on many-body perturbation theory. In addition, we generalize the quantum embedding theory to active spaces composed of orbitals that are not eigenstates of Kohn-Sham Hamiltonians. Finally, we report results for spin defects in semiconductors.
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http://dx.doi.org/10.1021/acs.jctc.0c01258DOI Listing
April 2021

Regulation of depression-related behaviors by GABAergic neurons in the lateral septum through periaqueductal gray neuronal projections.

J Psychiatr Res 2021 05 22;137:202-214. Epub 2021 Feb 22.

Institute for Metabolic & Neuropsychiatric Disorders, Binzhou Medical University Hospital, Binzhou, Shandong, China. Electronic address:

Major depressive disorder (MDD) is a serious and widespread mental illness worldwide. The abnormality of neuronal networks may contribute to the etiology of MDD. However, the neural connections underlying the main symptoms of MDD need further elucidation. Here, we found that GABAergic neurons in the lateral septum (LS) were activated by chronic unpredictable stress (CUS), with increased numbers of ΔFosB-labeled neurons. LS neuronal activity was modulated using a chemogenetic approach. Activation of LS neurons caused a depressive phenotype, as shown by increased immobility in the forced swim test, and induced increased susceptibility to subthreshold chronic stress, as indicated by decreased female urine sniffing time and preference for sucrose in depression-related behavior detection, whereas suppression of LS neuronal activity induced an antidepressant effect under basal and stressed conditions. Moreover, we found that the LS showed strong neuronal projections to the dorsal periaqueductal gray (dPAG); activation of dPAG-projecting GABAergic neurons in the LS produced the same depressive behaviors and stress susceptibility as induced by the activation of the majority of LS GABAergic neurons. Finally, we found that activation of neuronal fibers in the dPAG derived from the LS showed depression-related behaviors, as suggested by the decreased female urine sniffing time and sucrose preference in female urine sniffing and sucrose preference tests respectively. Our findings indicate that LS is a key depression-controlling nucleus, and that the LS-PAG projection is an essential effector circuit for morbidity and treatment in depression.
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http://dx.doi.org/10.1016/j.jpsychires.2021.02.043DOI Listing
May 2021

Management of high-energy tibial shaft fractures using the hexapod circular external fixator.

BMC Surg 2021 Feb 21;21(1):95. Epub 2021 Feb 21.

Department of Microrepair and Reconstruction, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, China.

Background: The hexapod external fixator (HEF) is increasingly used for high-energy tibial shaft fracture care as more general orthopedic surgeons are gaining expertise of this versatile device. The purpose of this study was to evaluate the clinical effectiveness of the HEF for definitive management in patients with high-energy tibial shaft fractures.

Methods: The study was conducted on 34 patients with tibial shaft fractures who were admitted or referred to our institution and consented to HEF treatment from Jan 2016 to June 2019, including 27 males and 7 females with a mean age of 39 years (range 18 to 65 years). Patients' clinical and radiological data, and the final clinical outcomes at a minimum of 12 months follow-up were collected and retrospectively analyzed. All complications were documented according to Paley's classification. The clinical outcomes were evaluated using the Association for the Study and Application of the Method of Ilizarov criteria (ASAMI) at the last clinical visit.

Results: All patients remained in the HEF for a mean of 26 weeks (range 15 to 52 weeks) and acquired complete bone union. The satisfactory alignment was achieved in all patients, and all the patients were able to perform daily activities with no difficulty at the last clinical visit. Complications included pin tract infection (44%), delayed union (6%), nonunion (3%), and joint stiffness (3%). The ASAMI bony result was excellent in 31 patients and good in 3. The ASAMI functional result was excellent in 27 patients, good in 6, and fair in 1.

Conclusions: Definitive management using the hexapod external fixator is an alternative and effective method for high-energy tibial shaft fractures, including technical advantages of early trauma-control, the versatility of achieving excellent alignment, and the continuity of device until bone union.
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http://dx.doi.org/10.1186/s12893-021-01106-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7897373PMC
February 2021

Selenium nanoparticles inhibit tumor metastasis in prostate cancer through upregulated miR-155-5p-related pathway.

Biosci Biotechnol Biochem 2021 Feb;85(2):287-296

Department of Urology, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China.

Prostate cancer are the most common, malignant and lethal tumors in men, and the complexity of prostate cancer (CaP) is also due to the diverse metastasis profile. Selenium nanoparticles (SeNPs) have been reported to have potent antitumor activity, but whether it impacted the tumor metastasis is not fully clear. Here, we confirmed that SeNPs could inhibit the CaP cell migrations and invasions. Combined with our previous findings, we identified a series of microRNAs that could be upregulated significantly under SeNP treatment, among which miR-155-5p acts as a key component in mediating the SeNP-inhibited migration and invasion of CaP cells, through directly targeting IκB kinase ɛ and Sma- and Mad-related protein 2. The cell-based results were proved in xenograft mice modeling. These results have evidently signified the antitumor potential of SeNPs in the treatment of prostate cancer.
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http://dx.doi.org/10.1093/bbb/zbaa089DOI Listing
February 2021

Identification of critical miRNAs and mRNAs associated with polycystic ovary syndrome.

J Obstet Gynaecol Res 2021 Apr 15;47(4):1416-1424. Epub 2021 Feb 15.

Department of Reproductive Medicine, Binzhou Medical University Hospital, Binzhou, Shandong, China.

Aim: Polycystic ovary syndrome (PCOS) is a complicated endocrine and metabolic abnormality diseases common in women of child-bearing age. This study aims to screen out critical miRNAs and mRNAs associated with PCOS, which may be conducive to offer novel insights and treatment for the diseases.

Methods: Three mRNA datasets and one miRNA dataset derived from granulosa cells of patients with PCOS and normal controls were downloaded to obtain the differentially expressed mRNAs (DEmRNAs) and miRNAs (DEmiRNAs). Then, DEmiRNA-target DEmRNAs analysis and functional annotation of DEmiRNA-target DEmRNAs were performed. Quantitative real time polymerase chain reaction (qRT-PCR) validation of the expression of the selected DEmRNAs and DEmiRNAs were performed.

Results: A total of 1643 DEmRNAs, 88 DEmiRNAs, 2406 DEmiRNA (down)-DEmRNA (up), and 2179 DEmiRNA (up)-DEmRNA (down) pairs were obtained. The functional annotation of DEmiRNA-target DEmRNAs revealed that C-type lectin receptor signaling pathway, Steroid biosynthesis and Galactose metabolism were significantly enriched KEGG pathways.

Conclusion: These findings may provide make contribution to understanding PCOS pathogenesis, diagnosis, or treatment.
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http://dx.doi.org/10.1111/jog.14707DOI Listing
April 2021

Rumen-bypassed tributyrin alleviates heat stress by reducing the inflammatory responses of immune cells.

Poult Sci 2021 Jan 13;100(1):348-356. Epub 2020 Oct 13.

College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, China.

Heat stress (HS) in summer will seriously affect the health and performance of dairy cows. To alleviate the injury to dairy cows caused by HS, we added the rumen-bypassed tributyrin to the feed. We determined whether cows were in a heat-stressed environment by testing the temperature humidity index in the morning, at noon, and in the evening. The detection of anal temperature and respiratory frequency further proved the HS state of the dairy cows. The quantificational real time PCR results showed that tributyrin could significantly reduce the relative expression of tumor necrosis factor α, interleukin 1β, and Interleukin 6. Western blot results showed that tributyrin could alleviate the lymphocyte inflammatory response by inhibiting the mitogen-activated protein kinase and nuclear factor-кB signaling pathways. To further detect the effect of tributyrin on HS in dairy cows, routine biochemical and blood tests were carried out. The results showed that the contents of aspartate aminotransferase, total bilirubin, creatinine, albumin, and globulin were significantly reduced by tributyrin. The results showed that tributyrin could significantly alleviate the liver and kidney injury induced by heat stress in dairy cows. Moreover, tributyrin could also significantly reduce the numbers of intermediate cells and increase the level of hemoglobin. Tributyrin could also improve the performance of dairy cows. These results suggested that tributylglycerol may have a positive effect on breast health of dairy cows. In conclusion, these results indicated that tributyrin could relieve HS and increase the production performance of dairy cows by reducing the inflammatory responses of lymphocytes.
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http://dx.doi.org/10.1016/j.psj.2020.10.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7772712PMC
January 2021

A size-tunable nanoplatform: enhanced MMP2-activated chemo-photodynamic immunotherapy based on biodegradable mesoporous silica nanoparticles.

Biomater Sci 2021 Feb;9(3):917-929

Institute of Biomedical Materials and Engineering, College of Materials Sciences and Engineering, Qingdao University, Qingdao 266071, China.

Although immunotherapy is emerging as a revolutionary strategy for cancer therapy, its clinical effect is severely impaired by adaptive immune evasion and inefficient activation of antitumor immune response. Photodynamic therapy and chemotherapy have been shown to efficiently enhance the therapeutic effect of PD-L1 immunotherapy via different mechanisms. However, the lack of a precise drug delivery system seriously impedes the clinical application of combination therapy. To address these restrictions, a matrix metalloproteinases-2 (MMP2)-activated shrinkable nanosystem was developed to potentiate the antitumor efficacy of anti-PD-L1 antibody (aPDL1) delivered along with a chemo-photodynamic therapy. The nanosystem maintains its structure to accelerate tumor accumulation and shrinks down to a smaller size to facilitate tumor penetration and cellular uptake upon arriving in the tumor microenvironment. The exposure of aPDL1 on the surface of the biodegradable mesoporous silica cores (bMSNs) blocks the PD-1/PD-L1 interaction between tumor cells and T cells. Meanwhile, photosensitizer chlorin e6 (Ce6) and paclitaxel (PTX) loaded bMSNs effectively enter tumor cells and induce chemo-photodynamic therapy. The nanosystem elicits a chemo-photodynamic-induced immune response and improves the therapeutic effect of PD-L1 blockade mediated by aPDL1. Furthermore, the nanosystem displays a sustained prohibitive effect on tumor metastasis to distant sites. Our work presents a promising strategy for enhancing the efficacy of cancer immunotherapy.
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http://dx.doi.org/10.1039/d0bm01452dDOI Listing
February 2021

Rich information on 2D materials revealed by optical second harmonic generation.

Nanoscale 2020 Nov;12(45):22891-22903

State Key Laboratory for Mesoscopic Physics, Collaborative Innovation Center of Quantum Matter, Academy for Advanced Interdisciplinary Studies, School of Physics, Peking University, Beijing, 100871, China.

Two-dimensional (2D) materials have brought a spectacular revolution in fundamental research and industrial applications due to their unique physical properties of atomically thin thickness, strong light-matter interaction, unity valley polarization and enhanced many-body interactions. To fully explore their exotic physical properties and facilitate potential applications in electronics and optoelectronics, an effective and versatile characterization method is highly demanded. Among the many methods of characterization, optical second harmonic generation (SHG) has attracted broad attention because of its sensitivity, versatility and simplicity. The SHG technique is sufficiently sensitive at the atomic scale and therefore suitable for studies on 2D materials. More importantly, it has the capacity to acquire abundant information ranging from crystallographic, and electronic, to magnetic properties in various 2D materials due to its sensitivity to both spatial-inversion symmetry and time-reversal symmetry. These advantages accompanied by its characteristics of non-invasion and high throughput make SHG a powerful tool for 2D materials. This review summarizes recent experimental developments of SHG applications in 2D materials and also provides an outlook of potential prospects based on SHG.
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http://dx.doi.org/10.1039/d0nr06051hDOI Listing
November 2020

First-principles studies of strongly correlated states in defect spin qubits in diamond.

Phys Chem Chem Phys 2020 Nov;22(44):25522-25527

Department of Chemistry, University of Chicago, Chicago, IL 60637, USA.

Using a recently developed quantum embedding theory, we present first-principles calculations of strongly correlated states of spin defects in diamond. Using this theory, effective Hamiltonians are constructed, which can be solved by classical and quantum computers; the latter promise a much more favorable scaling as a function of system size than the former. In particular, we report a study on the neutral group-IV vacancy complexes in diamond, and we discuss their strongly correlated spin-singlet and spin-triplet excited states. Our results provide valuable predictions for experiments aimed at optical manipulation of these defects for quantum information technology applications.
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http://dx.doi.org/10.1039/d0cp04585cDOI Listing
November 2020

Viewpoints on the 2020 Virtual Conference on Theoretical Chemistry.

J Phys Chem A 2020 Oct 15;124(43):8875-8883. Epub 2020 Oct 15.

Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States.

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http://dx.doi.org/10.1021/acs.jpca.0c08955DOI Listing
October 2020

A Multi-Label Deep Learning Model with Interpretable Grad-CAM for Diabetic Retinopathy Classification.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:1560-1563

The characteristics of diabetic retinopathy (DR) fundus images generally consist of multiple types of lesions which provided strong evidence for the ophthalmologists to make diagnosis. It is particularly significant to figure out an efficient method to not only accurately classify DR fundus images but also recognize all kinds of lesions on them. In this paper, a deep learning-based multi-label classification model with Gradient-weighted Class Activation Mapping (Grad-CAM) was proposed, which can both make DR classification and automatically locate the regions of different lesions. To reducing laborious annotation work and improve the efficiency of labeling, this paper innovatively considered different types of lesions as different labels for a fundus image so that this paper changed the task of lesion detection into that of image classification. A total of five labels were pre-defined and 3228 fundus images were collected for developing our model. The architecture of deep learning model was designed by ourselves based on ResNet. Through experiments on the test images, this method acquired a sensitive of 93.9% and a specificity of 94.4% on DR classification. Moreover, the corresponding regions of lesions were reasonably outlined on the DR fundus images.
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http://dx.doi.org/10.1109/EMBC44109.2020.9175884DOI Listing
July 2020

The inflammatory environment mediated by a high-fat diet inhibited the development of mammary glands and destroyed the tight junction in pregnant mice.

Food Funct 2020 Sep;11(9):8193-8201

College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, China.

Long-term intake of a high-fat diet seriously affects the health of pregnant women and leads to increased levels of inflammation in the mammary gland. Therefore, to further explore the effect of a high-fat diet on mammary gland development and the tight junction (TJ) during pregnancy, we placed mice into two groups: a high-fat diet group and a control group. We detected the expression of proteins related to fat synthesis in the mammary gland by western blotting. The results showed that a high-fat diet could lead to an increase in fat synthesis in the mammary gland. Then, the inflammatory levels and acinar cell morphology in the mammary gland were detected by ELISA and H&E staining. We also measured the levels of MAPK and NF-κB signal pathway-related proteins by western blotting. The results showed that a high-fat diet activated the MAPK and NF-κB signaling pathways and promoted the expression of inflammatory factors. Finally, the development of the mammary gland and the integrity of the TJ were determined by immunohistochemistry, immunofluorescence and western blotting. The results showed that a high-fat diet inhibited the development of the mammary gland and the expression of tight junction proteins (TJs). Our study showed that a high-fat diet could promote the expression of inflammatory factors by activating the MAPK and NF-κB signaling pathways and could reshape the microenvironment through extramammary inflammation. Finally, a high-fat diet inhibited the development of the mammary gland during pregnancy and destroyed the integrity of the TJ.
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http://dx.doi.org/10.1039/d0fo00609bDOI Listing
September 2020

Entanglement and control of single nuclear spins in isotopically engineered silicon carbide.

Nat Mater 2020 Dec 21;19(12):1319-1325. Epub 2020 Sep 21.

Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA.

Nuclear spins in the solid state are both a cause of decoherence and a valuable resource for spin qubits. In this work, we demonstrate control of isolated Si nuclear spins in silicon carbide (SiC) to create an entangled state between an optically active divacancy spin and a strongly coupled nuclear register. We then show how isotopic engineering of SiC unlocks control of single weakly coupled nuclear spins and present an ab initio method to predict the optimal isotopic fraction that maximizes the number of usable nuclear memories. We bolster these results by reporting high-fidelity electron spin control (F = 99.984(1)%), alongside extended coherence times (Hahn-echo T = 2.3 ms, dynamical decoupling T > 14.5 ms), and a >40-fold increase in Ramsey spin dephasing time (T*) from isotopic purification. Overall, this work underlines the importance of controlling the nuclear environment in solid-state systems and links single photon emitters with nuclear registers in an industrially scalable material.
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http://dx.doi.org/10.1038/s41563-020-00802-6DOI Listing
December 2020

Palmatine attenuates LPS-induced inflammatory response in mouse mammary epithelial cells through inhibiting ERK1/2, P38 and Akt/NF-кB signalling pathways.

J Anim Physiol Anim Nutr (Berl) 2021 Jan 31;105(1):183-190. Epub 2020 Aug 31.

College of Veterinary Medicine, Jilin University, Changchun, China.

Palmatine has a wide range of pharmacological effects and anti-inflammatory function. However, the effect of palmatine on LPS-induced inflammatory response of mammary epithelial cells has not been reported. In this research, we studied the anti-inflammatory mechanism of palmatine in EpH4-Ev (mouse mammary epithelial cells). EpH4-Ev cells were pre-treated with palmatine and then incubated with LPS. Cells were collected for examining production of pro-inflammatory mediators by qRT-PCR, and the related inflammatory signalling pathway was detected through immunofluorescence and Western blot. The results found that palmatine could significantly reduce the expression of IL-6, TNF-α, IL-1β and COX-2 in EpH4-Ev cells. Research on mechanisms found that palmatine could significantly inhibit the protein levels of p-Akt, p-P65, p-ERK1/2 and p-P38 in EpH4-Ev cells. In conclusion, these data suggested that palmatine inhibits inflammatory response in LPS-induced EpH4-Ev cells via down-regulating Akt/ NF-кB, ERK1/2 and P38 signalling pathways.
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http://dx.doi.org/10.1111/jpn.13440DOI Listing
January 2021

Sequence-based protein structure optimization using enhanced simulated annealing algorithm on a coarse-grained model.

J Mol Model 2020 Aug 24;26(9):250. Epub 2020 Aug 24.

College of Pharmaceutical and Bioengineering, Shenyang University of Chemical Technology, Shenyang, 110142, China.

The understanding of protein structure is vital to determine biological function. We presented an enhanced simulated annealing (ESA) algorithm to investigate protein three-dimensional (3D) structure on a coarse-grained model. Inside the algorithm, we adjusted exploration equations to achieve good search intensity. To that end, our algorithm used (i) a multivariable disturbance operator for diversification of solution, (ii) a sign function to improve randomness of solution, and (iii) taking remainder operation performed on floating-point number to tackle out-of-range solution. By monitoring energy value throughout the simulation, the energy-optimal state can be found. The ESA algorithm was tested on artificial and real protein sequences with different lengths. The results show that our algorithm outperforms conventional simulated annealing algorithm and can compete with the reported algorithms before. Especially, our algorithm can obtain folding conformations with specific structural features. Further analysis shows that simulating trajectory of seeking the lowest energy can exhibit thermodynamic behavior of protein folding. Graphical Abstract.
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http://dx.doi.org/10.1007/s00894-020-04490-6DOI Listing
August 2020

Enhanced Solar Photothermal Catalysis over Solution Plasma Activated TiO.

Adv Sci (Weinh) 2020 Aug 11;7(16):2000204. Epub 2020 Jun 11.

Key Laboratory of UV-Emitting Materials and Technology of Chinese Ministry of Education Northeast Normal University Changchun 130024 China.

Colored wide-bandgap semiconductor oxides with abundant mid-gap states have long been regarded as promising visible light responsive photocatalysts. However, their catalytic activities are hampered by charge recombination at deep level defects, which constitutes the critical challenge to practical applications of these oxide photocatalysts. To address the challenge, a strategy is proposed here that includes creating shallow-level defects above the deep-level defects and thermal activating the migration of trapped electrons out of the deep-level defects via these shallow defects. A simple and scalable solution plasma processing (SPP) technique is developed to process the presynthesized yellow TiO with numerous oxygen vacancies (Ov), which incorporates hydrogen dopants into the TiO lattice and creates shallow-level defects above deep level of Ov, meanwhile retaining the original visible absorption of the colored TiO. At elevated temperature, the SPP-treated TiO exhibits a 300 times higher conversion rate for CO reduction under solar light irradiation and a 7.5 times higher removal rate of acetaldehyde under UV light irradiation, suggesting the effectiveness of the proposed strategy to enhance the photoactivity of colored wide-bandgap oxides for energy and environmental applications.
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http://dx.doi.org/10.1002/advs.202000204DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7435248PMC
August 2020

Regulation of Female Folliculogenesis by Tsp1a in Nile Tilapia ().

Int J Mol Sci 2020 Aug 16;21(16). Epub 2020 Aug 16.

Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing 400715, China.

TSP1 was reported to be involved in multiple biological processes including the activation of TGF-β signaling pathways and the regulation of angiogenesis during wound repair and tumor growth, while its role in ovarian folliculogenesis remains to be elucidated. In the present study, Tsp1a was found to be expressed in the oogonia and granulosa cells of phase I to phase IV follicles in the ovaries of Nile tilapia by immunofluorescence. homozygous mutants were generated by CRISPR/Cas9. Mutation of resulted in increased oogonia, reduced secondary growth follicles and delayed ovary development. Expression of the cell proliferation marker PCNA was significantly up-regulated in the oogonia of the mutant ovaries. Furthermore, transcriptomic analysis revealed that expressions of DNA replication related genes were significantly up-regulated, while cAMP and MAPK signaling pathway genes which inhibit cell proliferation and promote cell differentiation were significantly down-regulated. In addition, aromatase (Cyp19a1a) expression and serum 17β-estradiol (E2) concentration were significantly decreased in the mutants. These results indicated that lacking resulted in increased proliferation and inhibited differentiation of oogonia, which in turn, resulted in increased oogonia, reduced secondary growth follicles and decreased E2. Taken together, our results indicated that was essential for ovarian folliculogenesis in Nile tilapia.
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http://dx.doi.org/10.3390/ijms21165893DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7460569PMC
August 2020
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