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1.
Macromol Rapid Commun ; 44(4): e2200705, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36461768

RESUMO

Hydrogel shape memory and actuating functionalities are heavily pursued and have found great potential in various application fields. However, their combination for more flexible and complicated morphing behaviors is still challenging. Herein, it is reported that by controlling the light-initiated polymerization of active hydrogel layers on shape memory hydrogel substrates, advanced morphing behaviors based on programmable hydrogel shapes and actuating trajectories are realized. The formation and photo-reduction-induced dissociation of Fe3+ -carboxylate coordination endow the hydrogel substrates with the shape memory functionality. The photo-reduced Fe2+ ions can diffuse from the substrates into the monomer solutions to initiate the polymerization of the thermally responsive active layers, whose actuating temperatures and amplitudes can be facially tuned by controlling their thicknesses and compositions. One potential application, a shape-programmable 3D hook that can lift an object with a specific shape, is also unveiled. The demonstrated strategy is extendable to other hydrogel systems to realize more versatile and complicated actuating behaviors.


Assuntos
Ácidos Carboxílicos , Hidrogéis , Hidrogéis/química , Temperatura , Polimerização , Íons
2.
Small ; 18(8): e2106427, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34889053

RESUMO

Lithium (Li) metal batteries (LMBs) face huge challenges to achieve long cycling life at wide temperature range owing to the severe dendrite growth at subambient temperature and the intense side reactions with electrolyte at high temperature. Herein, an ultrathin LiBO2 layer with an extremely high Young's modulus of 8.0 GPa is constructed on Li anode via an in situ reaction between Li metal and 4,4,5,5-tetramethyl-1,3,2-dioxa-borolane (TDB) to form LiBO2 @Li anode, which presents two times higher exchange current density than pristine Li anode. The LiBO2 layer presents a strong absorption to Li ions and greatly improves the interfacial dynamics of Li-ion migration, which induces homogenous lithium nucleation and deposition to form a dense lithium layer. Consequently, the Li dendrite growth during cycling at subambient temperature and the side reactions with electrolyte at high temperature are simultaneously suppressed. The LiBO2 @Li/LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) full batteries with limited Li capacity and high cathode mass loading of 9.9 mg cm-2 can steadily cycle for 300 cycles with a capacity retention of 86.6%. The LiBO2 @Li/NCM811 full batteries and LiBO2 @Li/LiBO2 @Li symmetric batteries also present excellent cycling performance at both -20 and 60 °C. This work develops a strategy to achieve outstanding performance of LMBs at wide working temperature-range.

3.
Phys Rev Lett ; 125(12): 126801, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016726

RESUMO

Doping a topological insulator (TI) film with transition metal ions can break its time-reversal symmetry and lead to the realization of the quantum anomalous Hall (QAH) effect. Prior studies have shown that the longitudinal resistance of the QAH samples usually does not vanish when the Hall resistance shows a good quantization. This has been interpreted as a result of the presence of possible dissipative conducting channels in magnetic TI samples. By studying the temperature- and magnetic-field-dependence of the magnetoresistance of a magnetic TI sandwich heterostructure device, we demonstrate that the predominant dissipation mechanism in thick QAH insulators can switch between nonchiral edge states and residual bulk states in different magnetic-field regimes. The interactions between bulk states, chiral edge states, and nonchiral edge states are also investigated. Our Letter provides a way to distinguish between the dissipation arising from the residual bulk states and nonchiral edge states, which is crucial for achieving true dissipationless transport in QAH insulators and for providing deeper insights into QAH-related phenomena.

4.
Nano Lett ; 18(4): 2530-2537, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29529371

RESUMO

Van der Waals structures formed by aligning monolayer graphene with insulating layers of hexagonal boron nitride exhibit a moiré superlattice that is expected to break sublattice symmetry. Despite an energy gap of several tens of millielectronvolts opening in the Dirac spectrum, electrical resistivity remains lower than expected at low temperature and varies between devices. While subgap states are likely to play a role in this behavior, their precise nature is unclear. We present a scanning gate microscopy study of moiré superlattice devices with comparable activation energy but with different charge disorder levels. In the device with higher charge impurity (∼1010 cm-2) and lower resistivity (∼10 kΩ) at the Dirac point we observe current flow along the graphene edges. Combined with simulations, our measurements suggest that enhanced edge doping is responsible for this effect. In addition, a device with low charge impurity (∼109 cm-2) and higher resistivity (∼100 kΩ) shows subgap states in the bulk, consistent with the absence of shunting by edge currents.

5.
J Chem Phys ; 148(5): 054101, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29421895

RESUMO

Random structure searching has been proved to be a powerful approach to search and find the global minimum and the metastable structures. A true random sampling is in principle needed yet it would be highly time-consuming and/or practically impossible to find the global minimum for the complicated systems in their high-dimensional configuration space. Thus the implementations of reasonable constraints, such as adopting system symmetries to reduce the independent dimension in structural space and/or imposing chemical information to reach and relax into low-energy regions, are the most essential issues in the approach. In this paper, we propose the concept of "object" which is either an atom or composed of a set of atoms (such as molecules or carbonates) carrying a symmetry defined by one of the Wyckoff positions of space group and through this process it allows the searching of global minimum for a complicated system to be confined in a greatly reduced structural space and becomes accessible in practice. We examined several representative materials, including Cd3As2 crystal, solid methanol, high-pressure carbonates (FeCO3), and Si(111)-7 × 7 reconstructed surface, to demonstrate the power and the advantages of using "object" concept in random structure searching.

6.
Gynecol Oncol ; 140(1): 131-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26616226

RESUMO

OBJECTIVE: Mucin (MUC) 20 has recently been implicated to play a role in human carcinogenesis. However, the role of MUC20 in epithelial ovarian cancer (EOC) remains to be elucidated. METHODS: MUC20 expression was assessed in tissue microarray and tumor specimens of EOC patients by immunohistochemistry. Effects of MUC20 on cell viability, adhesion, migration, and invasion were analyzed in MUC20 overexpressing or knockdown EOC cells. Western blotting was performed to analyze signaling pathways modulated by MUC20. RESULTS: MUC20 was overexpressed in EOC samples compared with benign tissues. High MUC20 expression was significantly associated with poor overall survival in patients with advanced-stage disease. MUC20 overexpression significantly enhanced EOC cell migration and invasion, but not viability. Mechanistic investigations showed that MUC20 increased cell adhesion to extracellular matrix (ECM) proteins and enhanced activation of integrin ß1 and phosphorylation of focal adhesion kinase (FAK). The enhancement of cell motility and the integrin ß1 signaling by MUC20 was significantly suppressed by integrin ß1 blocking antibody. Furthermore, these effects of MUC20 on EOC cells were also demonstrated in MUC20 knockdown cells. CONCLUSIONS: Our results suggest that MUC20 enhances aggressive behaviors of EOC cells by activating integrin ß1 signaling and provide novel insights into the role of MUC20 in ovarian cancer metastasis.


Assuntos
Integrina beta1/metabolismo , Mucinas/biossíntese , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Mucinas/genética , Mucinas/metabolismo , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Fenótipo , Transdução de Sinais
7.
BMC Genomics ; 15: 793, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25218338

RESUMO

BACKGROUND: Phage ZZ1, which efficiently infects pathogenic Acinetobacter baumannii strains, is the fifth completely sequenced T4-like Acinetobacter phage to date. To gain a better understanding of the genetic characteristics of ZZ1, bioinformatics and comparative genomic analyses of the T4 phages were performed. RESULTS: The 166,687-bp double-stranded DNA genome of ZZ1 has the lowest GC content (34.4%) of the sequenced T4-like Acinetobacter phages. A total of 256 protein-coding genes and 8 tRNA genes were predicted. Forty-three percent of the predicted ZZ1 proteins share up to 73% amino acid identity with T4 proteins, and the homologous genes generally retained the same order and transcriptional direction. Beyond the conserved structural and DNA replication modules, T4 and ZZ1 have diverged substantially by the acquisition and deletion of large blocks of unrelated genes, especially in the first halves of their genomes. In addition, ZZ1 and the four other T4-like Acinetobacter phage genomes (Acj9, Acj61, 133, and Ac42) share a well-organised and highly conserved core genome, particularly in the regions encoding DNA replication and virion structural proteins. Of the ZZ1 proteins, 70, 64, 61, and 56% share up to 86, 85, 81, and 83% amino acid identity with Acj9, Acj61, 133, and Ac42 proteins, respectively. ZZ1 has a different number and types of tRNAs than the other 4 Acinetobacter phages, although some of the ZZ1-encoded tRNAs share high sequence similarity with the tRNAs from these phages. Over half of ZZ1-encoded tRNAs (5 out of 8) are related to optimal codon usage for ZZ1 proteins. However, this correlation was not present in any of the other 4 Acinetobacter phages. CONCLUSIONS: The comparative genomic analysis of these phages provided some new insights into the evolution and diversity of Acinetobacter phages, which might elucidate the evolutionary origin and host-specific adaptation of these phages.


Assuntos
Acinetobacter/virologia , Bacteriófago T4/genética , Bacteriófago T4/fisiologia , Genoma Viral/genética , Composição de Bases , Códon/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Genômica , Anotação de Sequência Molecular , Filogenia , RNA de Transferência/genética
8.
Plant Cell Environ ; 37(9): 2201-10, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24506786

RESUMO

Controversies regarding the function of guard cell chloroplasts and the contribution of mesophyll in stomatal movements have persisted for several decades. Here, by comparing the stomatal opening of guard cells with (crl-ch) or without chloroplasts (crl-no ch) in one epidermis of crl (crumpled leaf) mutant in Arabidopsis, we showed that stomatal apertures of crl-no ch were approximately 65-70% those of crl-ch and approximately 50-60% those of wild type. The weakened stomatal opening in crl-no ch could be partially restored by imposing lower extracellular pH. Correspondingly, the external pH changes and K(+) accumulations following fusicoccin (FC) treatment were greatly reduced in the guard cells of crl-no ch compared with crl-ch and wild type. Determination of the relative ATP levels in individual cells showed that crl-no ch guard cells contained considerably lower levels of ATP than did crl-ch and wild type after 2 h of white light illumination. In addition, guard cell ATP levels were lower in the epidermis than in leaves, which is consistent with the observed weaker stomatal opening response to white light in the epidermis than in leaves. These results provide evidence that both guard cell chloroplasts and mesophyll contribute to the ATP source for H(+) extrusion by guard cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Cloroplastos/metabolismo , Células do Mesofilo/metabolismo , Estômatos de Plantas/citologia , Estômatos de Plantas/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Cloroplastos/efeitos dos fármacos , Cloroplastos/efeitos da radiação , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Espaço Extracelular/metabolismo , Glicosídeos/farmacologia , Concentração de Íons de Hidrogênio , Luz , Células do Mesofilo/efeitos dos fármacos , Células do Mesofilo/efeitos da radiação , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/efeitos da radiação , Potássio/metabolismo
9.
BMJ Open ; 14(5): e083888, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38821572

RESUMO

INTRODUCTION: Prolonged disorders of consciousness (pDoC) are a catastrophic condition following brain injury with few therapeutic options. Transcutaneous auricular vagal nerve stimulation (taVNS), a safe, non-invasive intervention modulating thalamo-cortical connectivity and brain function, is a possible treatment option of pDoC. We developed a protocol for a randomised controlled study to evaluate the effectiveness of taVNS on consciousness recovery in patients with pDoC (TAVREC). METHODS AND ANALYSIS: The TAVREC programme is a multicentre, triple-blind, randomised controlled trial with 4 weeks intervention followed by 4 weeks follow-up period. A minimum number of 116 eligible pDoC patients will be recruited and randomly receive either: (1) conventional therapy plus taVNS (30 s monophasic square current of pulse width 300 µs, frequency of 25 Hz and intensity of 1 mA followed by 30 s rest, 60 min, two times per day, for 4 weeks); or (2) conventional therapy plus taVNS placebo. Primary outcome of TAVREC is the rate of improved consciousness level based on the Coma Recovery Scale-Revised (CRS-R) at week 4. Secondary outcomes are CRS-R total and subscale scores, Glasgow Coma Scale score, Full Outline of UnResponsiveness score, ECG parameters, brainstem auditory evoked potential, upper somatosensory evoked potential, neuroimaging parameters from positron emission tomography/functional MRI, serum biomarkers associated with consciousness level and adverse events. ETHICS AND DISSEMINATION: This study was reviewed and approved by the Research Ethics Committee of the First Affiliated Hospital of Nanjing Medical University (Reference number: 2023-SR-392). Findings will be disseminated in a peer-reviewed journal and presented at relevant conferences. TRIAL REGISTRATION NUMBER: ChiCTR2300073950.


Assuntos
Transtornos da Consciência , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Adulto , Feminino , Humanos , Masculino , China , Estado de Consciência , Transtornos da Consciência/terapia , Transtornos da Consciência/fisiopatologia , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Estimulação Elétrica Nervosa Transcutânea/métodos , Resultado do Tratamento , Estimulação do Nervo Vago/métodos
10.
Gynecol Oncol ; 128(3): 560-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23262208

RESUMO

OBJECTIVE: Mucins play a critical role in the malignancy of various tumors and have been identified as diagnostic markers and as attractive therapeutic targets. However, the role of mucin (MUC) 20 in endometrial cancer (EC) is still unknown. METHODS: The relationship between MUC20 expression and clinical characteristics of EC was analyzed in 97 EC tumors and 16 normal tissues by immunohistochemistry. Effects of MUC20 on EC cells, HEC-1A and RL95-2, were examined by in vitro cell growth, migration, and invasion assays, as well as in vivo tumor growth in SCID mouse model. Western blotting was performed to analyze signaling pathways modulated by MUC20. RESULTS: MUC20 expression was significantly higher in EC tumors compared with the normal tissue. High levels of MUC20 expression in EC tumors were correlated with an unfavorable histologic subtype. Furthermore, MUC20 was an independent prognostic factor for poor survival as evaluated by multivariate analyses. Overexpression of MUC20 in EC cells significantly enhanced cell growth, migration, and invasion, as well as tumor growth in vivo. The MUC20-enhanced invasive behavior was significantly blocked by erlotinib, an EGFR inhibitor. Moreover, MUC20 overexpression enhanced EGF-mediated migration and invasion, suggesting a critical role of EGFR in MUC20-mediated effects. We found that MUC20 overexpression could enhance EGF-induced phosphorylation of EGFR and STAT3. Inhibition of the STAT3 activity by its inhibitor Stattic significantly suppressed the MUC20-enhanced invasive behavior. CONCLUSIONS: MUC20 is novel prognostic factor for EC and its overexpression enhances EGF-triggered invasive behavior through activation of EGFR-STAT3 pathway.


Assuntos
Neoplasias do Endométrio/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Mucinas/biossíntese , Fator de Transcrição STAT3/metabolismo , Animais , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Fator de Crescimento Epidérmico/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Mucinas/genética , Mucinas/metabolismo , Estadiamento de Neoplasias , Fenótipo , Fosforilação , Prognóstico , Fator de Transcrição STAT3/genética , Transdução de Sinais , Transfecção
11.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1806-1816, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694464

RESUMO

Forest canopy closure (FCC) is an important parameter to evaluate forest resources and biodiversity. Using multi-source remote sensing collaborative means to achieve regional forest canopy closure inversion with low cost and high-precision is a research hotspot. Taking ICESat-2/ATLAS data as the main information source and combined with data of 54 measured plots, we estimated FCC value by the Bayesian optimization (BO) algorithm improved random forest (RF), K-nearest neighbor (KNN), and gradient boosting regression tree (GBRT) model at footprint-scale. Combined with multi-source remote sensing image Sentinel-1/2 and terrain factors, we estimated the regional-scale FCC value of Shangri-La in the northwest Yunnan based on deep neural network (DNN) optimized by BO algorithm. The results showed that six characteristic parameters (percentage of tree canopy, standard deviation of relative height of photons at the top of the canopy, minimum canopy height, difference between 98% canopy height and median canopy height in the segment, number of top canopy photons, apparent surface reflectance) out of the 50 parameters that were extracted from ATLAS lidar footprint had higher contribution rate after RF characteristic variable optimization, which could be used as model variable for footprint-scale remote sensing estimation. Among BO-RF, BO-KNN, and BO-GBRT models, the FCC results estimated by the BO-GBRT model were the best at footprint-scale. The coefficient of determination (R2) was 0.65, the root mean square error (RMSE) was 0.10, the mean absolute residual (RS) was 0.079, and the prediction accuracy (P) was 0.792 for leave-one-out cross validation. It could be used as the FCC estimation model of 74808 ATLAS footprints for forest in the study area. We used the ATLAS footprint-scale FCC value of forest as the large sample data of the regional-scale BO-DNN model and combined with multi-source remote sensing factors to estimate FCC in the study area, the accuracy of the 10-fold cross-validation BO-DNN model was R2=0.47, RMSE=0.22, P=0.558. The mean values of FCC in the study area estimated by BO-DNN model and ordinary Kriging (OK) interpolation were 0.46 and 0.52, respectively, and the values mainly distributed in 0.3-0.6, accounting for 77.8% and 81.4%, respectively. The FCC efficiency obtained directly by the OK interpolation method was higher (R2=0.26), but the prediction accuracy was significantly lower than the BO-DNN model (R2=0.49). The FCC high value was distributed from northwest to southeast in the study area, and the northern and southeastern regions were the main distribution areas of high and low FCC values, respectively. It had certain advantages to estimate mountain area FCC based on ICESat-2/ATLAS high-density footprint, and the estimation results of small sample data at footprint-scale could be used as large sample data of deep learning model at region-scale, which would provide a reference for the low-cost and high-precision to FCC estimation on the footprint-scale up to the extrapolated regional-scale.


Assuntos
Algoritmos , Tecnologia de Sensoriamento Remoto , Teorema de Bayes , China , Biodiversidade
12.
BMC Microbiol ; 12: 156, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22838726

RESUMO

BACKGROUND: Acinetobacter baumannii, a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization. RESULTS: Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages. CONCLUSION: The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.


Assuntos
Acinetobacter baumannii/virologia , Bacteriófagos/isolamento & purificação , Bacteriófagos/fisiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Bacteriófagos/genética , Bacteriófagos/ultraestrutura , Caudovirales/genética , Caudovirales/isolamento & purificação , Caudovirales/fisiologia , Caudovirales/ultraestrutura , DNA Viral/química , DNA Viral/genética , Farmacorresistência Bacteriana Múltipla , Ordem dos Genes , Genoma Viral , Especificidade de Hospedeiro , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Dados de Sequência Molecular , Myoviridae/genética , Myoviridae/isolamento & purificação , Myoviridae/fisiologia , Myoviridae/ultraestrutura , Fases de Leitura Aberta , Análise de Sequência de DNA , Temperatura , Vírion/ultraestrutura
13.
J Nurs Res ; 30(3): e210, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35446283

RESUMO

BACKGROUND: The birth rate in Taiwan has declined rapidly; thus, encouraging women to give birth is an important issue in the country. Pregnant women may experience psychological distress, which may negatively impact the health of children and mothers. Prenatal psychological distress is more common in multiparous women than in primiparous women. In addition, compared with that in the second and third trimesters, psychological distress in the first trimester is relatively high. Understanding psychological distress and the associated factors for multiparous women in the first trimester is important to providing early interventions and preventing subsequent maternal and child health problems. PURPOSE: This study was designed to examine the important predictive factors related to depression, anxiety, and stress among Taiwanese multiparous women in the first trimester. METHODS: A cross-sectional design was used. In all, 216 multiparous women at 16 weeks of pregnancy were recruited from three hospitals in Taiwan. Self-reported questionnaires were used to gather data on demographic characteristics, the parenting stress of motherhood, spousal support, and psychological distress. A multiple logistic regression analysis was conducted to examine the factors associated with psychological distress. RESULTS: The prevalence of depression, anxiety, and stress in multiparous women was found to be 31.9%, 42.6%, and 11.1%, respectively. The multiple logistic regression analysis indicated that the stress related to parent-child interaction was a significant predictor of depression and anxiety, the stress related to child-rearing was a significant predictor of anxiety, and low spousal instrumental support was a significant predictor of stress. The model respectively explained 30%, 27%, and 23% of the variance in depression, anxiety, and stress. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: Reducing the stress related to parent-child interaction and child-rearing and encouraging spousal instrumental support should be considered during prenatal care when designing interventions to reduce the psychological distress of multiparous women in their first trimester.


Assuntos
Angústia Psicológica , Estresse Psicológico , Ansiedade/epidemiologia , Ansiedade/psicologia , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Gestantes/psicologia , Estresse Psicológico/complicações , Estresse Psicológico/psicologia
14.
RSC Adv ; 12(38): 24861-24867, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36128378

RESUMO

Solar-driven water vaporization is considered one of the most sustainable ways to solve water scarcity. The design of highly efficient solar absorber systems has received extensive attention. Here, we report a novel light absorption material for water evaporation using laser-treated wood. The obtained laser-treated wood possesses interconnected 3D porous networks formed by the random construction of carbon arrays and a hydrophilic surface due to the oxygen implantation by laser treatment. When under 1 sun solar-simulated light irradiation (1 kW m-2), the surface temperatures of dry and water-saturated wood reach 59.5 °C and 40.4 °C, respectively, indicating good heat localization. As a result, the laser-treated wood under 1 sun illumination shows high solar to vapor efficiencies of 93.1% and 92.6% for pure water and seawater, respectively, which are higher than that of most wood-based reported photo-thermal conversion materials. Therefore, the fabricated laser-treated wood may pave the way for harvesting solar energy to produce clean water at low cost.

15.
Nat Commun ; 13(1): 938, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177614

RESUMO

Reliable energy modules and higher-sensitivity, higher-density, lower-powered sensing systems are constantly required to develop wearable electronics and the Internet of Things technology. As an emerging technology, triboelectric nanogenerators have been potentially guiding the landscape of sustainable power units and energy-efficient sensors. However, the existing triboelectric series is primarily populated by polymers and rubbers, limiting triboelectric sensing plasticity to some extent owing to their stiff surface electronic structures. To enrich the current triboelectric group, we explore the triboelectric properties of the topological insulator nanofilm by Kelvin probe force microscopy and reveal its relatively positive electrification charging performance. Both the larger surface potential difference and the conductive surface states of the nanofilms synergistically improve the charge transfer behavior between the selected triboelectric media, endowing the topological insulator-based triboelectric nanogenerator with considerable output performance. Besides serving as a wearable power source, the ultra-compact device array demonstrates innovative system-level sensing capabilities, including precise monitoring of dynamic objects and real-time signal control at the human-machine interface. This work fills the blank between topological quantum matters and triboelectric nanogenerators and, more importantly, exploits the significant potential of topological insulator nanofilms for self-powered flexible/wearable electronics and scalable sensing technologies.

16.
Nanotechnology ; 22(33): 335701, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21775805

RESUMO

The electron transport behavior in chemically reduced graphene oxide (rGO) sheets with different thicknesses of 2, 3, and 5 nm was investigated. The four-probe method for the sheet resistance (R(S)) measurement on the intensively reduced graphene oxide samples indicates an Arrhenius characteristic of the electron transport at zero magnetic field B = 0, consistent with previous experimental results on well-reduced GO samples. The anticipated variable range hopping (VRH) transport of electrons in a two-dimensional electron system at low temperatures was not observed. The measured R(S) of the rGO samples are below 52 kΩ/square at room temperature. With the application of a magnetic field up to 4 T, negative magnetoresistance in the Mott VRH regime was observed. The magnetotransport features support a model based on the spin-coupling effect from the vacancy-induced midgap states that facilitate the Mott VRH conduction in the presence of an external magnetic field.

17.
Parasitol Res ; 108(3): 593-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20922411

RESUMO

The aim of this study was to observe the protein changes of intestinal epithelial cells induced in vitro by Trichinella spiralis infective larvae and their excretory-secretory (ES) or surface antigens and identity the proteins related with invasion. HCT-8 cells were incubated for 2 h in the culture medium contained ES or surface antigens of infective larvae, and observed by Immunofluorescent test (IFT). The infective larvae were inoculated into culture of HCT-8 cells to incubate for 18 h, and the lysates of HCT-8 cells were analyzed by SDS-PAGE and Western blot. IFA showed that normal HCT-8 cells had positively reactions with sera of the infected mice and mice immunized with ES or surface antigens. However, after incubating with ES or surface antigens, HCT-8 cells had stronger positively reaction with the above sera. On Western blot, after cultured with infective larvae, additional seven protein bands (66, 61, 57, 45, 34, 21, and 17 kDa) of HCT-8 cells were recognized by sera of the infected or immunized mice, but three protein bands (48, 43, and 23 kDa) of HCT-8 cells were not recognized by the above sera, compared with normal HCT-8 cells. Our results showed that after cultured with infective larvae the protein components of HCT-8 cell changed, suggesting that additional seven proteins recognized by sera of the infected or immunized mice may be related with invasion of intestinal epithelial cells by infective larvae, these proteins might mediate or facilitate entry into the cells, while the three proteins not recognized by the above sera may be the specific mediators released from the cells which permit invasion.


Assuntos
Antígenos de Helmintos/metabolismo , Antígenos de Superfície/metabolismo , Células Epiteliais/parasitologia , Proteínas de Helminto/metabolismo , Mucosa Intestinal/parasitologia , Trichinella spiralis/patogenicidade , Animais , Antígenos de Helmintos/imunologia , Antígenos de Superfície/imunologia , Western Blotting , Linhagem Celular Tumoral , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Imunofluorescência , Proteínas de Helminto/imunologia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Larva/imunologia , Larva/patogenicidade , Larva/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Trichinella spiralis/imunologia , Trichinella spiralis/fisiologia
18.
Life Sci ; 264: 118707, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33144187

RESUMO

Circular RNAs (circRNAs) are formed from the genome through diverse back splicing and feature the closed loop. circRNAs are widely available in a variety of cells and characterized by conservation, structural stability, high abundance and tissue-specific or developmental-specific expression. Recent studies have shown that circRNAs are closely related to liver diseases, such as metabolic-associated fatty liver disease, hepatitis, liver cirrhosis and hepatocellular carcinoma. circRNAs play an important role in the progression of liver diseases, are potential diagnostic and prognostic markers, and have translational value in therapy. This article reviews the research on circRNAs in liver diseases, with a view to providing a theoretical basis and new ideas for future research and treatment of liver diseases.


Assuntos
Hepatopatias/tratamento farmacológico , Hepatopatias/genética , RNA Circular/genética , Exossomos/metabolismo , Humanos , Oncogenes , RNA Circular/biossíntese , RNA Circular/metabolismo
19.
Artigo em Zh | MEDLINE | ID: mdl-21351546

RESUMO

OBJECTIVE: To observe the effect of sera from mice immunized with excretory-secretory (ES) antigen or surface antigen of Trichinella spiralis larvae on the invasion of intestinal epithelial cells in vitro by the larvae and on their development. METHODS: HCT-8 cells grown to confluence were overlaid with the larvae suspended in semisolid medium (RPMI 1640 medium +1.75% agarose), and the larvae were then observed by using an inverted microscope after being incubated at 37 degrees C under 5% CO2 for 12, 24, 36, 72, 96 h. The larval development and its invasion into intestinal epithelial cells were observed under inverted microscope after 15 min when HCT-8 cells were overlaid with the larvae suspended in semisolid medium supplemented with immune sera. Finally, the 1st stage and 2nd-4th stage larvae were observed and enumerated by indirect fluorescent antibody test (IFAT) after 36 h incubation. RESULTS: When the larvae were cultured in semisolid medium, they invaded the HCT-8 cell monolayer and molted 1-2 times at 36 h to 72 h of culture. Early adult was observed at 96 h of culture. Cephalic caps on larvae were found at 15 min of culture when the larvae were cultured with medium containing immune sera, but the caps were not observed on those cultured with sera of normal mice or without sera. And the larvae with cephalic caps did not invade the cell monolayer. When the larvae were cultured with immune sera for 36 h, the percentage of 2nd-4th stage larvae (2.25%, 2.20%) were significantly lower than that of those cultured in normal sera (24.7%) (P < 0.05). CONCLUSION: The sera from mice immunized with excretory-secretory antigen or surface antigen of T. spiralis larvae prevent the invasion of the larvae into intestinal epithelial cells in vitro and impede the development (ecdysis) of the larvae.


Assuntos
Células Epiteliais/parasitologia , Soros Imunes/imunologia , Trichinella spiralis/crescimento & desenvolvimento , Triquinelose , Animais , Antígenos de Helmintos/imunologia , Linhagem Celular , Células Epiteliais/imunologia , Humanos , Intestinos/citologia , Intestinos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos , Trichinella spiralis/imunologia , Trichinella spiralis/patogenicidade
20.
Artigo em Zh | MEDLINE | ID: mdl-20411747

RESUMO

OBJECTIVE: To observe the effect of edible vinegar or soy sauce on the infectivity and reproductive capacity of muscle larvae of Trichinella spiralis. METHODS: One hundred and forty male Kunming mice were randomly divided into 14 groups (10 mice per group). Mice in each group were orally fed with 300 muscle larvae in meat (weighing 0.02 g) soaked with edible vinegar (pH 3.05, 4.5% acid), soy (19.3% NaCl) or saline (control) for different time respectively. Half of the infected mice were sacrificed on day 7 and day 42 post-infection respectively. The intestinal adult worms and muscle larvae were observed, and reproductive capacity index (RCI) was determined. RESULTS: The intestinal adult worms (77, 41, 0, and 0, respectively) and RCI (52.48, 18.45, 0, and 0, respectively) in mice fed with 300 muscle larvae treated by vinegar for 3, 6, 12, and 24 h were considerably lower than that in saline control (worm number 121, 121, 116, and 101; RCI 159.10, 124.56, 73.63, and 42.17) (P<0.05). The intestinal adult worms (79.00, 39.00, 3.40, and 0) and RCI (48.75, 20.80, 1.87, and 0) in mice fed with soy-treated larvae for 12, 24, 36, and 48 h were also significantly lower than that in saline control (worm number 116, 101, 95, and 89; RCI 73.63, 42.17, 21.53, and 4.13) (P<0.05). Trend analysis showed that the intestinal adult worms and RCI of the infected mice decreased along with the increase of vinegar- or soy-soaking time (P<0.05). CONCLUSION: The infectivity and fecundity of T. spiralis muscle larvae decrease gradually after the treatment of edible vinegar or soy sauce.


Assuntos
Ácido Acético , Alimentos de Soja , Trichinella spiralis/fisiologia , Trichinella spiralis/patogenicidade , Animais , Fertilidade , Larva/patogenicidade , Larva/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos , Triquinelose
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