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1.
Technol Health Care ; 32(1): 379-395, 2024.
Article in English | MEDLINE | ID: mdl-37545287

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) endangers the physical and mental health of the elderly, constituting one of the most crucial social challenges. Due to lack of effective AD intervention drugs, it is very important to diagnose AD in the early stage, especially in the Mild Cognitive Impairment (MCI) phase. OBJECTIVE: At present, an automatic classification technology is urgently needed to assist doctors in analyzing the status of the candidate patient. The artificial intelligence enhanced Alzheimer's disease detection can reduce costs to detect Alzheimer's disease. METHODS: In this paper, a novel pre-trained ensemble-based AD detection (PEADD) framework with three base learners (i.e., ResNet, VGG, and EfficientNet) for both the audio-based and PET (Positron Emission Tomography)-based AD detection is proposed under a unified image modality. Specifically, the effectiveness of context-enriched image modalities instead of the traditional speech modality (i.e., context-free audio matrix) for the audio-based AD detection, along with simple and efficient image denoising strategy has been inspected comprehensively. Meanwhile, the PET-based AD detection based on the denoised PET image has been described. Furthermore, different voting methods for applying an ensemble strategy (i.e., hard voting and soft voting) has been investigated in detail. RESULTS: The results showed that the classification accuracy was 92% and 99% on the audio-based and PET-based AD datasets, respectively. Our extensive experimental results demonstrate that our PEADD outperforms the state-of-the-art methods on both audio-based and PET-based AD datasets simultaneously. CONCLUSIONS: The network model can provide an objective basis for doctors to detect Alzheimer's Disease.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Aged , Artificial Intelligence , Alzheimer Disease/diagnostic imaging , Positron-Emission Tomography/methods , Cognitive Dysfunction/diagnostic imaging , Magnetic Resonance Imaging/methods
2.
Front Oncol ; 13: 1207536, 2023.
Article in English | MEDLINE | ID: mdl-37675231

ABSTRACT

Epithelioid angiomyolipoma (EAML) is a rare type of mesenchymal angiomyolipoma with potential malignancy in the kidney that can cause lymph node metastases, local recurrence, and distant metastases. Herein, we describe a case of EAML in the right kidney of a 51-year-old man who was admitted to the hospital with a right abdominal mass. Computed tomography revealed a heterogeneously enhanced mass with blurred margins, which was considered a malignant tumor. A radical nephrectomy was then performed. Two years later, the patient developed liver metastases from EAML and was administered sintilimab combined with bevacizumab. The patient survived after 6 months of follow-up. Histologically, the tumors showed clear boundaries and no obvious capsules. The tumor tissue mainly consisted of epithelioid tumor cells, thick-walled blood vessels, and a small amount of adipose tissue. Tumor cells with lipid vacuoles and acinar areas were large, round, polygonal, eosinophilic, or transparent in the cytoplasm. The enlarged and hyperchromatic nuclei were accompanied by distinct nucleoli and pathological mitosis. These histopathological findings resembled those of renal cell carcinoma, and immunohistochemical analysis was performed. The tumor cells were diffusely positive for HMB45, Melan-A, CK20, vimentin antibodies, and TFE3, suggesting that the tumor originated from perivascular epithelioid cells, excluding renal cell carcinoma. The Ki-67 index was 10%. These histopathological features were observed in liver mass puncture tissues. We also summarized 46 cases of EAML with distant metastasis and explored the clinicopathological features of EAML to improve the treatment of the disease. EAML is often ignored in the clinical setting, leading to metastasis and recurrence. Therefore, EAMLs require long-term follow-up, and timely detection of recurrent disease can improve the prognosis.

3.
Small ; 19(49): e2303129, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37616518

ABSTRACT

Piezocatalysis has increasingly gained prominence due to its enormous potential for addressing energy shortages and environmental pollution issues. Nonetheless, the low piezocatalytic activity of state-of-the-art materials seriously inhibits the practical applications of piezocatalysis. Here, it is proposed to greatly enhance the piezocatalytic activity for a perovskite ferroelectric, i.e., Sm-doped 0.68Pb(Mg1/3 Nb2/3 )-0.32PbTiO3 (Sm-PMN-PT, a solid solution with ultrahigh piezoelectricity), by introducing oxygen vacancies (OVs). The results show that the presence of OVs promotes the production of reactive oxygen species while enhancing the adsorption and activation of organic pollutants to improve piezocatalytic performance. The OV-Sm-PMN-PT is found to possess a superior piezocatalytic degradation rate constant of 0.073 min-1 under ultrasonic vibration, which is ≈4.9 times higher than that of pristine Sm-PMN-PT. Furthermore, the OV-Sm-PMN-PT can efficiently remove RhB under 400 rpm stirring, making it a promising candidate for water purification using low-frequency mechanical energy from nature. This research sheds light on the design of piezocatalytic materials via defect engineering.

4.
Front Cell Dev Biol ; 11: 1208501, 2023.
Article in English | MEDLINE | ID: mdl-37534102

ABSTRACT

The optimization of culture conditions is one of the main strategies to improve the embryo development competence in in vitro fertilization (IVF). Glucose is an important carbon source while also exists in the oviductal fluid in vivo, the effect of glucose in embryo development microenvironment is still unclear. Here we employed the LC-MS to detect and analyze the metabolites in the culture medium of different cleavage stages including 2-Cell, 4-Cell and 8-Cell mouse embryos, respectively. The effects of the external glucose were estimated by measuring the development rate at different glucose concentrations from 0 to 5 mmol/L, and the gene expression changes were detected to explore the potential mechanism after the addition of glucose in the media. Our results indicated the 2-Cell and 8-Cell stages had defined characteristic metabolites, while 4-Cell stage was the transition state. Global and contiguous metabolic characteristics showed the glycometabolism play a critical role at each early cleavage stages during the embryo development. The 8-Cell rates demonstrated the addition of glucose in culture media significantly improve the embryo competence, the highest rate was 87.33% using 3 mmol/L glucose in media, in contrast only 9.95% using the media without glucose. Meanwhile, the blocked embryos were mainly enriched at 2-Cell stage. Further transcriptome study found 3 mmol/L glucose in media remarkably upregulated the gene expression of lipid biosynthesis at 2-Cell stage, the increased lipid was confirmed by nile red staining. These data indicated the glucose may promote the development competence through increasing the lipid biosynthesis to overcoming the 2-Cell block. Our findings were helpful for the further optimization of IVF culture media, as well as the estimation of embryo quality using metabolites in the culture media.

5.
Science ; 380(6640): 87-93, 2023 Apr 07.
Article in English | MEDLINE | ID: mdl-37023196

ABSTRACT

The piezoelectric properties of lead zirconate titanate [Pb(Zr,Ti)O3 or PZT] ceramics could be enhanced by fabricating textured ceramics that would align the crystal grains along specific orientations. We present a seed-passivated texturing process to fabricate textured PZT ceramics by using newly developed Ba(Zr,Ti)O3 microplatelet templates. This process not only ensures the template-induced grain growth in titanium-rich PZT layers but also facilitates desired composition through interlayer diffusion of zirconium and titanium. We successfully prepared textured PZT ceramics with outstanding properties, including Curie temperatures of 360°C, piezoelectric coefficients d33 of 760 picocoulombs per newton and g33 of 100 millivolt meters per newton, and electromechanical couplings k33 of 0.85. This study addresses the challenge of fabricating textured rhombohedral PZT ceramics by suppressing the otherwise severe chemical reaction between PZT powder and titanate templates.

6.
Front Oncol ; 12: 917366, 2022.
Article in English | MEDLINE | ID: mdl-36457496

ABSTRACT

Objective: The overexpression of polo-like kinase 1 (PLK-1) has been found in a broad spectrum of human tumors, making it an attractive prognostic tumor biomarker. Nowadays, PLK-1 is considered a cancer therapeutic target with clinical therapeutic value. The aim of the present study was to systematically review the prognostic and therapeutic value of PLK-1 in different malignant neoplasms. Methods: A systematic literature search of the Cochrane Library, PubMed, Web of Science, and China National Knowledge Internet (CNKI) databases was conducted between December 2018 and September 2022. In total, 41 published studies were screened, comprising 5,301 patients. We calculated the pooled odds ratios (ORs) and corresponding 95%CIs for the clinical parameters of patients included in these studies, as well as the pooled hazard ratios (HRs) and corresponding 95% CIs for 5-year overall survival (OS). Results: Our analysis included 41 eligible studies, representing a total of 5,301 patients. The results showed that overexpression of PLK-1 was significantly associated with poor OS (HR, 1.57; 95% CI, 1.18-2.08) and inferior 5-year disease-free survival/relapse-free survival ((HR, 1.89; 95% CI, 1.47-2.44). The pooled analysis showed that PLK-1 overexpression was significantly associated with lymph node metastasis, histological grade, clinical stages (p < 0.001 respectively), and tumor grade (p < 0.001). In digestive system neoplasms, PLK-1 overexpression was significantly associated with histopathological classification, primary tumor grade, histological grade, and clinical stages (p = 0.002, p = 0.001, p < 0.0001, respectively). In breast cancer, PLK-1 was significantly associated with 5-year overall survival, histological grade, and lymph node metastasis (p < 0.001, p = 0.003, p < 0.001, respectively). In the female reproductive system, PLK-1 was significantly associated with clinical stage (p = 0.011). In the respiratory system, PLK-1 was significantly associated with clinical stage (p = 0.021). Conclusion: Our analysis indicates that high PLK-1 expression is associated with aggressiveness and poor prognosis in malignant neoplasms. Therefore, PLK-1 may be a clinically valuable target for cancer treatment.

7.
Nanoscale Adv ; 4(12): 2704-2712, 2022 Jun 14.
Article in English | MEDLINE | ID: mdl-36132293

ABSTRACT

The structure of materials is closely related to their electrochemical properties. MnMoO4 materials have good stability as supercapacitors but their specific capacitance performance is not excellent. To improve electrochemical performance of MnMoO4, this study conducts secondary hydrothermal treatment in thiourea solution on MnMoO4 electrode material grown on nickel foam synthesized by traditional hydrothermal method. A more compact S-doped MnMoO4 electrode material with more oxygen vacancies and higher specific capacitance was obtained. At the current density of 1 A g-1, the specific capacitance of the composite material reached 2526.7 F g-1, which increased by 140.9% compared with that of ordinary MnMoO4 material. The capacitance retention rate of the composite material was 95.56% after 2000 cycles at 10 A g-1. An asymmetric supercapacitor was fabricated using S-doped MnMoO4 as the positive electrode, activated carbon as the negative electrode, and 6 mol L-1 KOH solution as the electrolyte. The specific capacitance of the assembled supercapacitor was 117.50 F g-1 at 1 A g-1, and a high energy density of 47.16 W h kg-1 at the power density of 849.98 W kg-1 was recorded. This method greatly improves the specific capacitance of MnMoO4 through simple processing, which makes it have great application potential.

8.
Front Cell Infect Microbiol ; 12: 927490, 2022.
Article in English | MEDLINE | ID: mdl-36004332

ABSTRACT

Group A rotaviruses (RVAs) are the most common etiological agents of severe acute diarrhea among children under 5 years old worldwide. At present, two live-attenuated RVA vaccines, LLR (G10P[15]) and RotaTeq (G1-G4, G6 P[8], P[5]), have been introduced to mainland China. Although RVA vaccines can provide homotypic and partially heterotypic protection against several strains, it is necessary to explore the genetic and antigenic variations between circulating RVAs and vaccine strains. In this study, we sequenced viral protein VP7 and VP4 outer capsid proteins of 50 RVA strains circulating in China from 2016 to 2019. The VP7 and VP4 sequences of almost all strains showed high homology to those of previously reported human strains and vaccine strains of the same genotype. However, in the presumed antigenic epitopes of the VP7 and VP4, multiple amino acid variations were found, regardless of the G and P genotypes of these strains. Moreover, all circulating G3 RVA strains in China potentially possess an extra N-linked glycosylation site compared with the G3 strain of RotaTeq. The potential N-linked glycosylation site at residues 69-71 was found in all G9 strains in China but not in the G9 strain of the Rotavac or Rotasill vaccine. These variations in antigenic sites might result in the selection of strains that escape the RVA neutralizing-antibody pressure imposed by vaccines. Furthermore, the G4 and P[6] genotypes in this study showed high homology to those of porcine strains, indicating the transmission of G4 and P[6] genotypes from pigs to humans in China. More genetic surveillance with antigenic evaluation in prevalent RVAs is necessary for developing and implementing rotavirus vaccines in China.


Subject(s)
Antigens, Viral , Rotavirus Infections , Rotavirus , Viral Proteins , Animals , Antigens, Viral/genetics , Capsid Proteins , Child , Child, Preschool , Chin , Diarrhea/epidemiology , Epitopes/genetics , Genotype , Humans , Phylogeny , Rotavirus/genetics , Rotavirus Infections/prevention & control , Swine , Viral Proteins/genetics
9.
Environ Sci Pollut Res Int ; 29(58): 88172-88181, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35831647

ABSTRACT

A novel magnetic catalyst was synthesized and applied in heterogeneous catalytic ozonation process. The ZnFe2O4/ZnNCN material was synthesized by hydrothermal and high-temperature calcination method and characterized by XPS, XRD, FTIR, VSM, and SEM techniques. In the system of O3/ZnFe2O4/ZnNCN, the removal rates of phenol and chemical oxygen demand (COD) reached 93% and 43% at 60 min. Further analysis shows that ZnFe2O4/ZnNCN has a significant catalytic effect on O3, which is demonstrated by the first-order kinetic constant being 1.93 times than O3 alone. The catalyst exhibits excellent cycling stability during repeated catalytic ozonation process and can be fully recycled under an applied magnetic field. The role of hydrogen peroxide (H2O2) and surface hydroxyl groups was investigated, and a mechanism for catalytic ozonation was proposed. This work not only builds an efficient catalytic ozonation system, but also provides a potential modification strategy for spinel oxides.


Subject(s)
Ozone , Water Pollutants, Chemical , Phenol/chemistry , Ozone/chemistry , Hydrogen Peroxide , Water Pollutants, Chemical/analysis , Catalysis , Phenols/analysis
10.
ACS Appl Mater Interfaces ; 14(22): 25427-25438, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35621374

ABSTRACT

Rechargeable Zn-air batteries have received extensive attention due to their use of nontoxic materials, safety, and high energy density. However, the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the air electrode of Zn-air batteries both suffer from slow kinetics, limiting their commercialization development. Herein, we prepared Co, N, and S co-doped hollow carbon nanoboxes (Co-N/S-CNBs) rich in topological defects using polyphenylene sulfide (PPS) as a sulfur-rich carbon source. Critically, by utilizing the self-propagating high-temperature synthesis (SHS), PPS can avoid melting, while simultaneously enabling the catalyst to take on a unique hollow structure. Additional post-treatment to introduce Co and N atoms as active centers further increases the defect sites and microporous structures of the catalyst. Under alkaline electrolytes, the Co-N/S-CNBs enabled Zn-air batteries to exhibit excellent bifunctional catalytic activity for both ORR and OER, surpassing commercial catalysts. Chemical analysis showed that the cracking loss of small molecules from PPS during pyrolysis is the main reason for the formation of topological defects, where the defect sites act as active centers to enhance the catalytic performance. Overall, this work provides new insights into the mechanism of how defects are formed in such a catalyst, as well as shows how a high-performance bifunctional electrocatalyst can be utilized for practical Zn-air batteries.

11.
Front Mol Neurosci ; 15: 854000, 2022.
Article in English | MEDLINE | ID: mdl-35493329

ABSTRACT

Background: Diabetic peripheral neuropathic pain (DPNP) is a usual complication of diabetes with a high incidence and mortality. Many diabetes-related studies have been published in various journals. However, bibliometrics and visual analyses in the domain of DPNP research are still lacking. The study aimed to offer a visual method to observe the systematic overview of global research in this field from 2011 to 2021. Methods: The publications from the Science Citation Index Expanded in Web of Science (WOS) in the past 11 years (from 2011 to 2021) were collected and sorted out, and those related to DPNP were extracted and analyzed. The article language was limited in English. Then, CiteSpace V was used for the bibliometric analysis of the extracted literature. Results: A total of 1,422 articles met the inclusion criteria. A continuous but unstable growth in the amounts of papers published on DPNP was observed over the last 11 years. The subject sort of the 1,422 papers mainly concentrates on Endocrinology Metabolism, Clinical neurology and Neurosciences from the WOS. According to the research contribution in the field of DPNP, the United States occupies a leading position, with the highest amounts of publications, citations, open access, and the H- index. Conclusion: This study provides a visual analysis method for the trend of DPNP, and offers some hidden serviceable information that may define new directions for future research.

12.
Infect Genet Evol ; 101: 105287, 2022 07.
Article in English | MEDLINE | ID: mdl-35487436

ABSTRACT

Rotavirus A (RVA) G3P[8] is sporadically detected in China, although G9P[8] predominates. To evaluate their genetic composition at the whole-genome level, 24 G3P[8] RVA strains isolated from children under five years were sequenced and characterized. The 24 strains were genotyped as G3-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, indicating the Wa-like genotype constellation. A maximum clade credibility (MCC) tree for VP7 indicated that G3 had an estimated mean evolutionary rate of 7.279 × 10-4 substitutions/site/year; thus, 3-5 years would pass from the generation of an ancestor virus to the epidemic spread of that virus throughout China. Considering the ongoing prevalence as well as rapid evolution, it is important to monitor G3P[8] RVA epidemics; continuous nationwide surveillance is essential.


Subject(s)
Rotavirus Infections , Rotavirus , Child , Child, Preschool , Genome, Viral , Genomics , Genotype , Humans , Phylogeny , Rotavirus/genetics
13.
Sensors (Basel) ; 22(6)2022 Mar 14.
Article in English | MEDLINE | ID: mdl-35336406

ABSTRACT

Finger vein recognition has drawn increasing attention as one of the most popular and promising biometrics due to its high distinguishing ability, security, and non-invasive procedure. The main idea of traditional schemes is to directly extract features from finger vein images and then compare features to find the best match. However, the features extracted from images contain much redundant data, while the features extracted from patterns are greatly influenced by image segmentation methods. To tackle these problems, this paper proposes a new finger vein recognition algorithm by generating code. The proposed method does not require an image segmentation algorithm, is simple to calculate, and has a small amount of data. Firstly, the finger vein images were divided into blocks to calculate the mean value. Then, the centrosymmetric coding was performed using the matrix generated by blocking and averaging. The obtained codewords were concatenated as the feature codewords of the image. The similarity between vein codes is measured by the ratio of minimum Hamming distance to codeword length. Extensive experiments on two public finger vein databases verify the effectiveness of the proposed method. The results indicate that our method outperforms the state-of-the-art methods and has competitive potential in performing the matching task.


Subject(s)
Algorithms , Fingers , Biometry/methods , Databases, Factual , Fingers/blood supply , Veins/diagnostic imaging
14.
Virol Sin ; 36(5): 1187-1196, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34057680

ABSTRACT

P[3] rotavirus (RV) has been identified in many species, including human, simian, dog, and bat. Several glycans, including sialic acid, histo-blood group antigens (HBGAs) are reported as RV attachment factors. The glycan binding specificity of different P[3] RV VP8*s were investigated in this study. Human HCR3A and dog P[3] RV VP8*s recognized glycans with terminal sialic acid and hemagglutinated the red blood cells, while bat P[3] VP8* showed neither binding to glycans nor hemagglutination. However, the bat P[3] VP8* mutant of C189Y obtained the ability to hemagglutinate the red blood cells, while human P[3] HCR3A/M2-102 mutants of Y189C lost the ability. Sequence alignment and structural analysis indicated that residue 189 played an important role in the ligand recognition and may contribute to the cross-species transmission. Structural superimposition exhibited that bat P[3] VP8* model was quite different from the simian P[3] Rhesus rotavirus (RRV) P[3] VP8*, indicating that bat P[3] RV was relatively distinct and partially contributed to the no binding to tested glycans. These results promote our understanding of P[3] VP8*/glycans interactions and the potential transmission of bat/human P[3] RVs, offering more insight into the RV infection and prevalence.


Subject(s)
Blood Group Antigens , Chiroptera , Rotavirus Infections , Rotavirus , Animals , Dogs , Humans , Viral Nonstructural Proteins/genetics
15.
Nat Commun ; 12(1): 1414, 2021 Mar 03.
Article in English | MEDLINE | ID: mdl-33658525

ABSTRACT

The figure-of-merits of ferroelectrics for transducer applications are their electromechanical coupling factor and the operable temperature range. Relaxor-PbTiO3 ferroelectric crystals show a much improved electromechanical coupling factor k33 (88~93%) compared to their ceramic counterparts (65~78%) by taking advantage of the strong anisotropy of crystals. However, only a few relaxor-PbTiO3 systems, for example Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3, can be grown into single crystals, whose operable temperature range is limited by their rhombohedral-tetragonal phase transition temperatures (Trt: 60~120 °C). Here, we develop a templated grain-growth approach to fabricate <001>-textured Pb(In1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3-PbTiO3 (PIN-PSN-PT) ceramics that contain a large amount of the refractory component Sc2O3, which has the ability to increase the Trt of the system. The high k33 of 85~89% and the greatly increased Trt of 160~200 °C are simultaneously achieved in the textured PIN-PSN-PT ceramics. The above merits will make textured PIN-PSN-PT ceramics an alternative to single crystals, benefiting the development of numerous advanced piezoelectric devices.

16.
Front Cell Dev Biol ; 9: 749486, 2021.
Article in English | MEDLINE | ID: mdl-35004670

ABSTRACT

Although sperm preservation is a common means of personal fertility preservation, its effects on embryonic development potential need further investigation. The purpose of this study was to identify key microRNA (miRNA) in cryopreserved sperm and determine the changes of these miRNAs and their target genes during embryonic development using cryopreserved sperm. Moreover, the embryonic development potential of cryopreserved sperm was estimated in assisted reproductive technology (ART), where key miRNAs and target genes were validated in sperm and subsequent embryos. Clinical data of embryonic development from cryopreserved sperm indicated a significant decrease in fertilization rate in both in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cases, as well as a reduction in blastocyst formation rate in ICSI cases. Meanwhile there was a significant increase in blocked embryo ratio of Day1, Day2, and Day3.5 embryos when frozen-thawed mouse sperm was used, compared with fresh mouse sperm, suggesting a potential negative effect of sperm cryopreservation on embryonic development. From frozen-thawed and fresh sperm in humans and mice, respectively, 21 and 95 differentially expressed miRNAs (DEmiRs) were detected. miR-148b-3p were downregulated in both human and mouse frozen-thawed sperm and were also decreased in embryos after fertilization using cryopreserved sperm. Target genes of miR-148b-3p, Pten, was identified in mouse embryos using quantitative real-time PCR (qRT-PCR) and Western blot (WB). In addition, common characters of cryopreservation of mouse oocytes compared with sperm were also detected; downregulation of miR-148b-3p was also confirmed in cryopreserved oocytes. In summary, our study suggested that cryopreservation of sperm could change the expression of miRNAs, especially the miR-148b-3p across humans and mice, and may further affect fertilization and embryo development by increasing the expression of Pten. Moreover, downregulation of miR-148b-3p induced by cryopreservation was conserved in mouse gametes.

17.
Nat Mater ; 19(9): 999-1005, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32541934

ABSTRACT

Dielectric ceramics are highly desired for electronic systems owing to their fast discharge speed and excellent fatigue resistance. However, the low energy density resulting from the low breakdown electric field leads to inferior volumetric efficiency, which is the main challenge for practical applications of dielectric ceramics. Here, we propose a strategy to increase the breakdown electric field and thus enhance the energy storage density of polycrystalline ceramics by controlling grain orientation. We fabricated high-quality <111>-textured Na0.5Bi0.5TiO3-Sr0.7Bi0.2TiO3 (NBT-SBT) ceramics, in which the strain induced by the electric field is substantially lowered, leading to a reduced failure probability and improved Weibull breakdown strength, on the order of 103 MV m-1, an ~65% enhancement compared to their randomly oriented counterparts. The recoverable energy density of <111>-textured NBT-SBT multilayer ceramics is up to 21.5 J cm-3, outperforming state-of-the-art dielectric ceramics. The present research offers a route for designing dielectric ceramics with enhanced breakdown strength, which is expected to benefit a wide range of applications of dielectric ceramics for which high breakdown strength is required, such as high-voltage capacitors and electrocaloric solid-state cooling devices.

18.
IET Syst Biol ; 12(6): 264-272, 2018 12.
Article in English | MEDLINE | ID: mdl-30472690

ABSTRACT

Quantitative analyses of biological networks such as key biological parameter estimation necessarily call for the use of graphical models. While biological networks with feedback loops are common in reality, the development of graphical model methods and tools that are capable of dealing with feedback loops is still in its infancy. Particularly, inadequate attention has been paid to the parameter identifiability problem for biological networks with feedback loops such that unreliable or even misleading parameter estimates may be obtained. In this study, the structural identifiability analysis problem of time-invariant linear structural equation models (SEMs) with feedback loops is addressed, resulting in a general and efficient solution. The key idea is to combine Mason's gain with Wright's path coefficient method to generate identifiability equations, from which identifiability matrices are then derived to examine the structural identifiability of every single unknown parameter. The proposed method does not involve symbolic or expensive numerical computations, and is applicable to a broad range of time-invariant linear SEMs with or without explicit latent variables, presenting a remarkable breakthrough in terms of generality. Finally, a subnetwork structure of the C. elegans neural network is used to illustrate the application of the authors' method in practice.


Subject(s)
Computational Biology/methods , Feedback, Physiological , Models, Biological , Animals , Caenorhabditis elegans/metabolism , Nerve Net/metabolism , Time Factors
20.
Sci Rep ; 6: 25297, 2016 04 29.
Article in English | MEDLINE | ID: mdl-27126145

ABSTRACT

Deception is not a rare occurrence among human behaviors; however, the present brain mapping techniques are insufficient to reveal the neural mechanism of deception under spontaneous or controlled conditions. Interestingly, functional near-infrared spectroscopy (fNIRS) has emerged as a highly promising neuroimaging technique that enables continuous and noninvasive monitoring of changes in blood oxygenation and blood volume in the human brain. In this study, fNIRS was used in combination with complex network theory to extract the attribute features of the functional brain networks underling deception in subjects exhibiting spontaneous or controlled behaviors. Our findings revealed that the small-world networks of the subjects engaged in spontaneous behaviors exhibited greater clustering coefficients, shorter average path lengths, greater average node degrees, and stronger randomness compared with those of subjects engaged in control behaviors. Consequently, we suggest that small-world network topology is capable of distinguishing well between spontaneous and controlled deceptions.


Subject(s)
Brain Mapping , Brain/physiology , Deception , Functional Neuroimaging , Nerve Net , Spectroscopy, Near-Infrared , Adult , Female , Humans , Male , Young Adult
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