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1.
Small ; 20(29): e2312167, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38634275

RESUMO

3D composite electrodes have shown extraordinary promise as high mass loading electrode materials for sodium ion batteries (SIBs). However, they usually show poor rate performance due to the sluggish Na+ kinetics at the heterointerfaces of the composites. Here, a 3D MXene-reduced holey graphene oxide (MXene-RHGO) composite electrode with Ti─O─C bonding at 2D heterointerfaces of MXene and RHGO is developed. Density functional theory (DFT) calculations reveal the built-in electric fields (BIEFs) are enhanced by the formation of bridged interfacial Ti─O─C bonding, that lead to not only faster diffusion of Na+ at the heterointerfaces but also faster adsorption and migration of Na+ on the MXene surfaces. As a result, the 3D composite electrodes show impressive properties for fast Na+ storage. Under high current density of 10 mA cm-2, the 3D MXene-RHGO composite electrodes with high mass loading of 10 mg cm-2 achieve a strikingly high and stable areal capacity of 3 mAh cm-2, which is same as commercial LIBs and greatly exceeds that of most reported SIBs electrode materials. The work shows that rationally designed bonding at the heterointerfaces represents an effective strategy for promoting high mass loading 3D composites electrode materials forward toward practical SIBs applications.

2.
Neuroendocrinology ; 114(5): 411-422, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38228117

RESUMO

INTRODUCTION: Aging is characterized by the deterioration of a wide range of functions in tissues and organs, and Alzheimer's disease (AD) is a neurodegenerative disease characterized by cognitive impairment. Hypothyroidism occurs when there is insufficient production of thyroid hormones (THs) by the thyroid. The relationship between hypothyroidism and aging as well as AD is controversial at present. METHODS: We established an animal model of AD (FAD4T) with mutations in the APP and PSEN1 genes, and we performed a thyroid function test and RNA sequencing (RNA-Seq) of the thyroid from FAD4T and naturally aging mice. We also studied gene perturbation correlation in the FAD4T mouse thyroid, bone marrow, and brain by further single-cell RNA sequencing (scRNA-seq) data of the bone marrow and brain. RESULTS: In this study, we found alterations in THs in both AD and aging mice. RNA-seq data showed significant upregulation of T-cell infiltration- and cell proliferation-related genes in FAD4T mouse thyroid. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that upregulated genes were enriched in the functional gene modules of activation of immune cells. Downregulated energy metabolism-related genes were prominent in aging thyroids, which reflected the reduction in THs. GSEA showed a similar enrichment tendency in both mouse thyroids, suggesting their analogous inflammation state. In addition, the regulation of leukocyte activation and migration was a common signature between the thyroid, brain, and bone marrow of FAD4T mice. CONCLUSIONS: Our findings identified immune cell infiltration of the thyroid as the potential underlying mechanism of the alteration of THs in AD and aging.


Assuntos
Envelhecimento , Doença de Alzheimer , Modelos Animais de Doenças , Presenilina-1 , Hormônios Tireóideos , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Envelhecimento/metabolismo , Camundongos , Hormônios Tireóideos/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , Glândula Tireoide/metabolismo , Camundongos Transgênicos , Encéfalo/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Masculino
3.
Sensors (Basel) ; 24(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39066147

RESUMO

Road cracks significantly affect the serviceability and safety of roadways, especially in mountainous terrain. Traditional inspection methods, such as manual detection, are excessively time-consuming, labor-intensive, and inefficient. Additionally, multi-function detection vehicles equipped with diverse sensors are costly and unsuitable for mountainous roads, primarily because of the challenging terrain conditions characterized by frequent bends in the road. To address these challenges, this study proposes a customized Unmanned Aerial Vehicle (UAV) inspection system designed for automatic crack detection. This system focuses on enhancing autonomous capabilities in mountainous terrains by incorporating embedded algorithms for route planning, autonomous navigation, and automatic crack detection. The slide window method (SWM) is proposed to enhance the autonomous navigation of UAV flights by generating path planning on mountainous roads. This method compensates for GPS/IMU positioning errors, particularly in GPS-denied or GPS-drift scenarios. Moreover, the improved MRC-YOLOv8 algorithm is presented to conduct autonomous crack detection from UAV imagery in an on/offboard module. To validate the performance of our UAV inspection system, we conducted multiple experiments to evaluate its accuracy, robustness, and efficiency. The results of the experiments on automatic navigation demonstrate that our fusion method, in conjunction with SWM, effectively enables real-time route planning in GPS-denied mountainous terrains. The proposed system displays an average localization drift of 2.75% and a per-point local scanning error of 0.33 m over a distance of 1.5 km. Moreover, the experimental results on the road crack detection reveal that the MRC-YOLOv8 algorithm achieves an F1-Score of 87.4% and a mAP of 92.3%, thus surpassing other state-of-the-art models like YOLOv5s, YOLOv8n, and YOLOv9 by 1.2%, 1.3%, and 3.0% in terms of mAP, respectively. Furthermore, the parameters of the MRC-YOLOv8 algorithm indicate a volume reduction of 0.19(×106) compared to the original YOLOv8 model, thus enhancing its lightweight nature. The UAV inspection system proposed in this study serves as a valuable tool and technological guidance for the routine inspection of mountainous roads.

4.
BMC Genomics ; 24(1): 329, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322464

RESUMO

BACKGROUND: Branching is a plastic character that affects plant architecture and spatial structure. The trait is controlled by a variety of plant hormones through coordination with environmental signals. Plant AT-rich sequence and zinc-binding protein (PLATZ) is a transcription factor that plays an important role in plant growth and development. However, systematic research on the role of the PLATZ family in apple branching has not been conducted previously. RESULTS: In this study, a total of 17 PLATZ genes were identified and characterized from the apple genome. The 83 PLATZ proteins from apple, tomato, Arabidopsis, rice, and maize were classified into three groups based on the topological structure of the phylogenetic tree. The phylogenetic relationships, conserved motifs, gene structure, regulatory cis-acting elements, and microRNAs of the MdPLATZ family members were predicted. Expression analysis revealed that MdPLATZ genes exhibited distinct expression patterns in different tissues. The expression patterns of the MdPLATZ genes were systematically investigated in response to treatments that impact apple branching [thidazuron (TDZ) and decapitation]. The expression of MdPLATZ1, 6, 7, 8, 9, 15, and 16 was regulated during axillary bud outgrowth based on RNA-sequencing data obtained from apple axillary buds treated by decapitation or exogenous TDZ application. Quantitative real-time PCR analysis showed that MdPLATZ6 was strongly downregulated in response to the TDZ and decapitation treatments, however, MdPLATZ15 was significantly upregulated in response to TDZ, but exhibited little response to decapitation. Furthermore, the co-expression network showed that PLATZ might be involved in shoot branching by regulating branching-related genes or mediating cytokinin or auxin pathway. CONCLUSION: The results provide valuable information for further functional investigation of MdPLATZ genes in the control of axillary bud outgrowth in apple.


Assuntos
Decapitação , Malus , Malus/metabolismo , Filogenia , Decapitação/metabolismo , Genes de Plantas , Brotos de Planta/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Liver Transpl ; 25(8): 1251-1264, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152624

RESUMO

Liver transplantation (LT) is currently considered an important method in treating hepatocellular carcinoma (HCC) and an alternative treatment for other liver malignancies. Here, we demonstrated that the graft-versus-tumor (GVT) effect exists in allogeneic liver transplantation (allo LT). Recipient-derived T cells played a critical role in the GVT process of allo LT, as demonstrated by extensive infiltration and significant activation of recipient T cells in the tumor after surgery. Moreover, this process was related to donor-derived T/B cells by improving the immune microenvironment in the tumor, as demonstrated by elevated levels of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), IL-6, IL-16, chemokine (C-X-C motif) ligand 10 (CXCL10), and CXCL11 and decreased levels of IL-10 and IL-4 at tumor sites. Additionally, tacrolimus (FK506) treatment inhibited the GVT effect on allo LT. Donor liver-derived T/B cells infiltrate extrahepatic tumors to trigger a strong T-cell-mediated immune response and thus improve the tumor immune microenvironment.


Assuntos
Carcinoma Hepatocelular/cirurgia , Efeito Enxerto vs Tumor/imunologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Microambiente Tumoral/imunologia , Aloenxertos/imunologia , Animais , Carcinoma Hepatocelular/imunologia , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Efeito Enxerto vs Tumor/efeitos dos fármacos , Humanos , Imunossupressores/administração & dosagem , Isoantígenos/imunologia , Fígado/imunologia , Neoplasias Hepáticas/imunologia , Masculino , Camundongos , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Tacrolimo/administração & dosagem , Transplante Homólogo , Microambiente Tumoral/efeitos dos fármacos
6.
Molecules ; 24(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775267

RESUMO

Widespread in citrus fruits, naringin, a natural 2,3-dihydroflavonoid, is of particular interest to scientists and has a broad range of beneficial bioactivities to health. Orally administered naringin remains in the gut tract for a relatively long time because of its low bioavailability. Under the metabolism mediated by human gut microbiota, naringin could be an active precursor for derived metabolites to play important physiological roles. However, naringin and its metabolites are hard to accurately quantify due to severe endogenic interference. In this study, an analytical rapid resolution liquid chromatography tandem mass spectrometry (RRLC-MS/MS) method coupled with stable isotope deuterium-labeling is developed and validated to simultaneously quantify naringin as well as its major human gut microbial metabolites naringenin and 3-(4'-hydroxyphenyl) propanoic acid. By eliminating the matrix interferences, this strategy not only confirms naringenin and 3-(4'-hydroxyphenyl) propanoic acid as the predominant metabolites which contribute to the pharmacological effects of naringin but also provides a suitable choice for other flavonoid pharmacokinetics study.


Assuntos
Flavanonas/química , Metaboloma , Propionatos/química , Cromatografia Líquida de Alta Pressão , Citrus/química , Deutério/química , Flavanonas/genética , Flavanonas/isolamento & purificação , Flavonoides/química , Microbioma Gastrointestinal , Humanos , Marcação por Isótopo , Propionatos/isolamento & purificação , Espectrometria de Massas em Tandem
7.
Small ; 14(11): e1703321, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29325204

RESUMO

Multidrug resistance (MDR) remains one of the biggest obstacles in chemotherapy of tumor mainly due to P-glycoprotein (P-gp)-mediated drug efflux. Here, a transformable chimeric peptide is designed to target and self-assemble on cell membrane for encapsulating cells and overcoming tumor MDR. This chimeric peptide (C16 -K(TPE)-GGGH-GFLGK-PEG8 , denoted as CTGP) with cathepsin B-responsive and cell membrane-targeting abilities can self-assemble into nanomicelles and further encapsulate the therapeutic agent doxorubicin (termed as CTGP@DOX). After the cleavage of the Gly-Phe-Leu-Gly (GFLG) sequence by pericellular overexpressed cathepsin B, CTGP@DOX is dissociated and transformed from spherical nanoparticles to nanofibers due to the hydrophilic-hydrophobic conversion and hydrogen bonding interactions. Thus obtained nanofibers with cell membrane-targeting 16-carbon alkyl chains can adhere firmly to the cell membrane for cell encapsulation and restricting DOX efflux. In comparison to free DOX, 45-time higher drug retention and 49-fold greater anti-MDR ability of CTGP@DOX to drug-resistant MCF-7R cells are achieved. This novel strategy to encapsulate cells and reverse tumor MDR via morphology transformation would open a new avenue towards chemotherapy of tumor.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Peptídeos/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membrana Celular/metabolismo , Doxorrubicina/química , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7
8.
Phys Rev Lett ; 121(8): 086805, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192625

RESUMO

Collective electron transport causes a weakly coupled semiconductor superlattice under dc voltage bias to be an excitable system with 2N+2 degrees of freedom: electron densities and fields at N superlattice periods plus the total current and the field at the injector. External noise of sufficient amplitude induces regular current self-oscillations (coherence resonance) in states that are stationary in the absence of noise. Numerical simulations show that these oscillations are due to the repeated nucleation and motion of charge dipole waves that form at the emitter when the current falls below a critical value. At the critical current, the well-to-well tunneling current intersects the contact load line. We have determined the device-dependent critical current for the coherence resonance from experiments and numerical simulations. We have also described through numerical simulations how a coherence resonance triggers a stochastic resonance when its oscillation mode becomes locked to a weak ac external voltage signal. Our results agree with the experimental observations.

9.
Phys Rev Lett ; 121(8): 086806, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192582

RESUMO

The effect of a coherence resonance is observed experimentally in a GaAs/Al_{0.45}Ga_{0.55}As superlattice under dc bias at room temperature, which is driven by noise. For an applied voltage, for which no current self-oscillations are observed, regular current self-oscillations with a frequency of about 82 MHz are induced by exceeding a certain noise amplitude. In addition, a novel kind of a stochastic resonance is identified, which is triggered by the coherence resonance. This stochastic resonance appears when the device is driven by an external ac signal with a frequency, which is relatively close to that of the regular current self-oscillations at the coherence resonance. The intrinsic oscillation mode in the coherence resonance is found to be phase locked by an extremely weak ac signal. It is demonstrated that an excitable superlattice device can be used for the fast detection of weak signals submerged in noise. These results are very well reproduced by results using numerical simulations based on a sequential resonant tunneling model of nonlinear electron transport in semiconductor superlattices.

10.
Biometals ; 31(5): 749-757, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30027360

RESUMO

Recently, more and more studies indicate that iron overload would cause osteopenia or osteoporosis. However, the molecular mechanism of it remains unclear. Moreover, very little is known about the iron metabolism in bone tissue at present. Therefore, the mRNA expression of iron-regulators, transferrin receptor1 (Tfr1), divalent metal transporter1 (Dmt1 + IRE and Dmt1 - IRE), ferritin (FtH and FtL), and ferroportin1 (Ireg1), and the localization of ferroportin1 protein were examined in the bone tissue of rats. In addition, the mRNA expression of each gene was compared between groups of rats with and without iron overload. The results showed that ferroportin1 protein was localized in the cytoplasm of osteoblast, osteocyte, chondrocyte and osteoclast of rats' femur. The six iron-regulatory genes, Tfr1, ferritin (FtH and FtL), (Dmt1 + IRE and Dmt1 - IRE) and ferroportin1 (Ireg1), were found in femurs of rats. In addition, significantly up-regulated expression of FtH and FtL mRNA, and markedly down-regulated expression of Tfr1, Dmt1 + IRE and Ireg1 mRNA, were observed in the iron overload group compared with the control group. The result indicates that ferroportin1 protein is localized in the cytoplasm of bone cells of rats. Tfr1, Dmt1, ferritin and ferroportin1 exist in bone tissue of rats, and they may be involved in the pathological process of iron overload-induced bone lesion.


Assuntos
Fêmur/metabolismo , Sobrecarga de Ferro/metabolismo , Proteínas de Ligação ao Ferro/genética , Proteínas de Ligação ao Ferro/metabolismo , Animais , Fêmur/citologia , Masculino , Ratos , Ratos Sprague-Dawley
11.
Small ; 13(37)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783253

RESUMO

Tumor hypoxia severely limits the efficacy of traditional photodynamic therapy (PDT). Here, a liposome-based nanoparticle (designated as LipoMB/CaO2 ) with O2 self-sufficient property for dual-stage light-driven PDT is demonstrated to address this problem. Through a short time irradiation, 1 O2 activated by the photosensitizer methylene blue (MB) can induce lipid peroxidation to break the liposome, and enlarge the contact area of CaO2 with H2 O, resulting in accelerated O2 production. Accelerated O2 level further regulates hypoxic tumor microenvironment and in turn improves 1 O2 generation by MB under another long time irradiation. In vitro and in vivo experiments also demonstrate the superior competence of LipoMB/CaO2 to alleviate tumor hypoxia, suppress tumor growth and antitumor metastasis with low side-effect. The O2 self-sufficient LipoMB/CaO2 nanoplatform with dual-stage light manipulation is a successful attempt for PDT against hypoxic tumor.


Assuntos
Luz , Nanopartículas/química , Oxigênio/química , Fotoquimioterapia , Hipóxia Tumoral , Animais , Apoptose , Peso Corporal , Compostos de Cálcio/química , Linhagem Celular Tumoral , Lipossomos , Azul de Metileno , Camundongos , Nanopartículas/ultraestrutura , Necrose , Óxidos/química , Carga Tumoral , Difração de Raios X
12.
Chemistry ; 21(50): 18187-91, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26542735

RESUMO

Hierarchical hybridized nanocomposites with rationally constructed compositions and structures have been considered key for achieving superior Li-ion battery performance owing to their enhanced properties, such as fast lithium ion diffusion, good collection and transport of electrons, and a buffer zone for relieving the large volume variations during cycling processes. Hierarchical MoS2 @carbon microspheres (HMCM) have been synthesized in a facile hydrothermal treatment. The structure analyses reveal that ultrathin MoS2 nanoflakes (ca. 2-5 nm) are vertically supported on the surface of carbon nanospheres. The reversible capacity of the HMCM nanocomposite is maintained at 650 mA h g(-1) after 300 cycles at 1 A g(-1) . Furthermore, the capacity can reach 477 mA h g(-1) even at a high current density of 4 A g(-1) . The outstanding electrochemical performance of HMCM is attributed to the synergetic effect between the carbon spheres and the ultrathin MoS2 nanoflakes. Additionally, the carbon matrix can supply conductive networks and prevent the aggregation of layered MoS2 during the charge/discharge process; and ultrathin MoS2 nanoflakes with enlarged surface areas, which can guarantee the flow of the electrolyte, provide more active sites and reduce the diffusion energy barrier of Li(+) ions.

13.
Nano Lett ; 14(3): 1293-9, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24559146

RESUMO

Development of novel electrolytes with increased electrochemical stability is critical for the next generation battery technologies. In situ electrochemical fluid cells provide the ability to rapidly and directly characterize electrode/electrolyte interfacial reactions under conditions directly relevant to the operation of practical batteries. In this paper, we have studied the breakdown of a range of inorganic/salt complexes relevant to state-of-the-art Li-ion battery systems by in situ (scanning) transmission electron microscopy ((S)TEM). In these experiments, the electron beam itself caused the localized electrochemical reaction that allowed us to observe electrolyte breakdown in real-time. The results of the in situ (S)TEM experiments matches with previous stability tests performed during battery operation and the breakdown products and mechanisms are also consistent with known mechanisms. This analysis indicates that in situ liquid stage (S)TEM observations could be used to directly test new electrolyte designs and identify a smaller library of candidate solutions deserving of more detailed characterization. A systematic study of electrolyte degradation is also a necessary first step for any future controlled in operando liquid (S)TEM experiments intent on visualizing working batteries at the nanoscale.

14.
Nano Lett ; 14(12): 6889-96, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25419865

RESUMO

Suppressing lithium (Li) dendrite growth is one of the most critical challenges for the development of Li metal batteries. Here, we report for the first time the growth of dendrite-free lithium films with a self-aligned and highly compacted nanorod structure when the film was deposited in the electrolyte consisting of 1.0 M LiPF6 in propylene carbonate with 0.05 M CsPF6 as an additive. Evolution of both the surface and the cross-sectional morphologies of the Li films during repeated Li deposition/stripping processes were systematically investigated. It is found that the formation of the compact Li nanorod structure is preceded by a solid electrolyte interphase (SEI) layer formed on the surface of the substrate. Electrochemical analysis indicates that an initial reduction process occurred at ∼ 2.05 V vs Li/Li(+) before Li deposition is responsible for the formation of the initial SEI, while the X-ray photoelectron spectroscopy indicates that the presence of CsPF6 additive can largely enhance the formation of LiF in this initial SEI. Hence, the smooth Li deposition in Cs(+)-containing electrolyte is the result of a synergistic effect of Cs(+) additive and preformed SEI layer. A fundamental understanding on the composition, internal structure, and evolution of Li metal films may lead to new approaches to stabilize the long-term cycling stability of Li metal and other metal anodes for energy storage applications.


Assuntos
Eletrodos , Lítio/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Cristalização/métodos , Galvanoplastia/métodos , Teste de Materiais , Propriedades de Superfície
15.
Tumour Biol ; 35(3): 2069-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24132591

RESUMO

MicroRNAs are a class of small noncoding RNAs that function as critical gene regulators through targeting mRNAs for translational repression or degradation. Several studies have indicated that abnormal expression of miRNAs occurs frequently in human osteosarcoma. In the present study, we found that miR-128 expression was significantly increased in osteosarcoma tissues compared to adjacent normal tissues. Ectopic overexpression of miR-128 significantly promoted while suppression of miR-128 by its antisense inhibited the proliferation of MG63 and U2OS cells. At the molecular level, our results demonstrated that miR-128 overexpression could repress expression of PTEN by directly targeting PTEN 3'-untranslated region. Consistently, downstream AKT signaling was altered by miR-128 overexpression or knockdown. Therefore, our results suggest that miR-128 plays an important role in the proliferation of human osteosarcoma cells by directly regulation of PTEN/AKT signaling.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Osteossarcoma/genética , PTEN Fosfo-Hidrolase/biossíntese , Western Blotting , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Osteossarcoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Transfecção
16.
ScientificWorldJournal ; 2014: 748634, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592182

RESUMO

Hair is a salient feature in human face region and are one of the important cues for face analysis. Accurate detection and presentation of hair region is one of the key components for automatic synthesis of human facial caricature. In this paper, an automatic hair detection algorithm for the application of automatic synthesis of facial caricature based on a single image is proposed. Firstly, hair regions in training images are labeled manually and then the hair position prior distributions and hair color likelihood distribution function are estimated from these labels efficiently. Secondly, the energy function of the test image is constructed according to the estimated prior distributions of hair location and hair color likelihood. This energy function is further optimized according to graph cuts technique and initial hair region is obtained. Finally, K-means algorithm and image postprocessing techniques are applied to the initial hair region so that the final hair region can be segmented precisely. Experimental results show that the average processing time for each image is about 280 ms and the average hair region detection accuracy is above 90%. The proposed algorithm is applied to a facial caricature synthesis system. Experiments proved that with our proposed hair segmentation algorithm the facial caricatures are vivid and satisfying.


Assuntos
Algoritmos , Identificação Biométrica/métodos , Caricaturas como Assunto , Cabelo/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Face/anatomia & histologia , Humanos
17.
Nano Lett ; 13(12): 6106-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24224495

RESUMO

Over the past few years, in situ transmission electron microscopy (TEM) studies of lithium ion batteries using an open-cell configuration have helped us to gain fundamental insights into the structural and chemical evolution of the electrode materials in real time. In the standard open-cell configuration, the electrolyte is either solid lithium oxide or an ionic liquid, which is point-contacted with the electrode. This cell design is inherently different from a real battery, where liquid electrolyte forms conformal contact with electrode materials. The knowledge learnt from open cells can deviate significantly from the real battery, calling for operando TEM technique with conformal liquid electrolyte contact. In this paper, we developed an operando TEM electrochemical liquid cell to meet this need, providing the configuration of a real battery and in a relevant liquid electrolyte. To demonstrate this novel technique, we studied the lithiation/delithiation behavior of single Si nanowires. Some of lithiation/delithation behaviors of Si obtained using the liquid cell are consistent with the results from the open-cell studies. However, we also discovered new insights different from the open cell configuration-the dynamics of the electrolyte and, potentially, a future quantitative characterization of the solid electrolyte interphase layer formation and structural and chemical evolution.


Assuntos
Lítio/química , Nanofios/química , Silício/química , Fontes de Energia Elétrica , Eletroquímica , Eletrodos , Microscopia Eletrônica de Transmissão , Propriedades de Superfície
18.
iScience ; 27(8): 110491, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39171291

RESUMO

Dual-ion batteries (DIBs) offer high energy density due to the ability to intercalate both anions and cations, thereby increasing the cutoff voltage and battery capacity. Graphite, with its ordered layered structure and cost-effectiveness, is commonly employed as the cathode material for DIBs. However, the discharge capacity of graphite cathodes is relatively low, and their cycling stability is poor, limiting the practical applications of DIBs. The formation of cathode electrolyte interphase (CEI) on the graphite cathode surface is closely related to anion behavior. Constructing a stable cathode electrolyte interface is crucial for improving the stability of anion storage. Therefore, we introduce a series of strategies to enhance the quality of the CEI layer, including additives, binders, main salts or solvents, high-concentration electrolytes, doping elements, artificial CEI, and graphite surface modifications. These strategies improve the CEI by enhancing anion transport rates, increasing anion solvation capabilities, and improving the structural stability of graphite cathodes, which is of profound significance for increasing the capacity and stability of DIBs. This review provides inspiration for future CEI research, encouraging further exploration of resources of CEI components and improvement strategies to further promote the development of DIBs technology.

19.
Sci Rep ; 14(1): 15939, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987651

RESUMO

In order to grasp the influence of the pH value of mixing water and environmental water on the properties of ultra-high water materials, this article separately carried out the influence of different pH values of mixing water on the properties of ultra-high water materials and the conservation of high-water materials in water environments with different pH values. Using test methods such as loss of flow time, compressive strength, Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Thermogravimetric-Differential Thermal Analysis (TG-DTA), to conduct regular exploration and mechanism analysis. The study found that with the continuous increase of the pH value of the mixing water, the loss of flow time of the ultra-high water material gradually decreased, and the compressive strength of the samples at the same age continued to increase. A lower pH value will affect the compressive strength of the consolidated body of the ultra-high water material, but when the pH = 13 in the reaction solution, the compressive strength of the consolidated body will no longer increase and begin to produce a weakening effect. The pH of the construction water for ultra-high water materials is recommended to be 4-13. At the same time, it was found that under the conservation of an acidic environment, the consolidated body was severely eroded and the strength loss was large. The acid-base environment of the goaf suitable for filling with the ultra-high water material should be between pH = 7-10 to ensure that the filling body is not weakened by erosion.

20.
Sci Rep ; 14(1): 15114, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956155

RESUMO

Wheat straw returning is a common agronomic measure in the farmland. Understanding organic carbon transformation is of great significance for carbon budget under the premise of widespread distribution of cadmium (Cd) contaminated soils. An incubation experiment was conducted to assess the influence of Cd contamination on the decomposition and accumulation of total organic carbon (TOC) as well as the composition and abundance of bacterial communities in eight soil types with wheat straw addition. The results showed that inhibition of Cd contamination on microbially mediated organic carbon decomposition was affected by soil types. The lower cumulative C mineralization and higher TOC content could be observed in the acidic soils relative to that in the alkaline soils. The content of Cd in soil exhibits different effects on the inhibition in decomposition of TOC. The high dosage level of Cd had stronger inhibitory impact due to its high toxicity. The decomposition of TOC was restricted by a reduction in soil bacterial abundance and weakening of bacterial activities. Redundancy analysis (RDA) indicated that Proteobacteria and Gemmatimonadetes were abundant in alkaline Cd-contaminated soils with wheat straw addition, while Bacteroidetes dominated cumulative C mineralization in acidic Cd-contamination soils. Moreover, the abundance of predicted functional bacteria indicated that high-dose Cd-contamination and acid environment all inhibited the decomposition of TOC. The present study suggested that pH played an important role on carbon dynamics in the Cd-contaminated soils with wheat straw addition.


Assuntos
Cádmio , Carbono , Microbiologia do Solo , Poluentes do Solo , Solo , Triticum , Cádmio/metabolismo , Cádmio/análise , Triticum/metabolismo , Triticum/química , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Carbono/metabolismo , Carbono/análise , Solo/química , Bactérias/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio
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