Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Phys Rev Lett ; 131(22): 226802, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101373

RESUMO

HfO_{2}-based ferroelectric thin films are promising for their application in ferroelectric devices. Predicting the ultimate magnitude of polarization and understanding its switching mechanism are critical to realize the optimal performance of these devices. Here, a generalized solid-state variable cell nudged elastic band method is employed to predict the switching pathway associated with domain-wall motion in (Hf,Zr)O_{2} ferroelectrics. It is found that the polarization reversal pathway, where threefold coordinated O atoms pass across the nominal unit-cell boundaries defined by the Hf/Zr atomic planes, is energetically more favorable than the conventional pathway where the O atoms do not pass through these planes. This finding implies that the polarization orientation in the orthorhombic Pca2_{1} phase of HfO_{2} and its derivatives is opposite to that normally assumed, predicts the spontaneous polarization magnitude of about 70 µC/cm^{2} that is nearly 50% larger than the commonly accepted value, signifies a positive intrinsic longitudinal piezoelectric coefficient, and suggests growth of ferroelectric domains, in response to an applied electric field, structurally reversed to those usually anticipated. These results provide important insights into the understanding of ferroelectricity in HfO_{2}-based ferroelectrics.

2.
Biomarkers ; 26(6): 532-538, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34020571

RESUMO

BACKGROUND: Hypercoagulation starts as early as the first-trimester pregnancy and is a risk factor for thromboembolic events which are associated with miscarriage. Our study aimed to investigate coagulation, platelets, and fibrinolysis parameters alteration amongst trimester-specific normal pregnancy and first-trimester miscarriage patients. We also test the accuracy of haemostatic parameters determination for prediction of first-trimester miscarriage. METHODS: Retrospective investigation of 50 women whose most recent pregnancy had ended in the first trimester and 54 age-matched consecutive normal pregnancy between 2016 and 2019. Furthermore, 51 non-pregnant, age-matched women were included in parallel to healthy controls. Twelve screening tests for coagulation and platelet parameters were assessed. RESULTS: We found plasma levels of aPTT, FBG, and TT were significantly prolonged or decreased in miscarriage subjects than the corresponding first phase in normal pregnancies. PT, INR, aPTT, and d-dimer all shift back to normal in miscarriage patients compared with non-pregnant women. Shortened aPTT combined with TT and FBG can predicted the occurrence of first-trimester miscarriage with an AUC of 0.831. CONCLUSIONS: Routine assessment of aPTT combined with TT and FBG is a low-cost, widely available marker for prediction of first-trimester miscarriage.


Assuntos
Aborto Espontâneo/sangue , Hemostasia , Monitorização Fisiológica/métodos , Primeiro Trimestre da Gravidez , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Testes Hematológicos , Humanos , Gravidez , Estudos Retrospectivos , Fatores de Risco
3.
Medicine (Baltimore) ; 103(31): e39141, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093804

RESUMO

Identifying depression symptoms in patients with hip fractures and studying the relationship between depression and pain intensity and pain location in hip fracture patients is of great significance for disease recovery in hip fracture patients. This cohort study analyzed 5 wave data from the China Health and Retirement Longitudinal Study in 2011, 2013, 2015, 2018, and 2020, focusing on 1222 patients with hip fractures. The study utilized the CESD-10 Depression Scale to assess depressive symptoms in hip fracture patients and conducted analyses to explore the relationship between depression symptoms, pain, and pain intensity, including binary logistic regression and examination of interaction terms between pain variables and pain intensity in key body parts. Depression symptoms are strongly associated with pain intensity in hip fracture patients, particularly in key body areas. Severe pain significantly increases the risk of depressive symptoms. Moreover, absence of pain in other key body parts is linked to depressive symptoms. Multivariate analysis reveals that higher education levels, marriage, urban residence, and self-rated good health serve as protective factors against depression, while diabetes and heart disease pose significant risks for depressive symptoms in hip fracture patients. Hip fracture pain can induce discomfort and trigger depressive symptoms, showing varied trajectories among patients. Pain intensity predicts the course of depressive symptoms, emphasizing the importance of tailored pain management strategies including medication, physical therapy, and nonpharmacological interventions. Personalized rehabilitation and mental health plans should be designed based on individual patient needs and differences.


Assuntos
Depressão , Fraturas do Quadril , Dor , Humanos , Fraturas do Quadril/psicologia , Fraturas do Quadril/complicações , Fraturas do Quadril/epidemiologia , Feminino , Masculino , Idoso , Depressão/epidemiologia , Depressão/etiologia , China/epidemiologia , Dor/psicologia , Dor/etiologia , Dor/epidemiologia , Estudos Longitudinais , Pessoa de Meia-Idade , Medição da Dor , Idoso de 80 Anos ou mais , Fatores de Risco
4.
Hematology ; 28(1): 2264517, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37815499

RESUMO

OBJECTIVE: Multiple Myeloma (MM) is a hematologic malignant disease with unclear molecular mechanisms. This integrated bioinformatic study aimed to identify key genes, pathways and immune cell infiltration pattern in MM. METHODS: Differentially expressed genes (DEGs) from GSE6477 and GSE16558 dataset were filtrated with R package 'limma', whose function were explored by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The key genes were selected from Protein-protein interaction network (PPI) and logistic regression model. The correlation between key genes and survival in MM was evaluated using the survival and survminer package. Additionally, immune filtration analysis was accomplished by CIBERSORT tools. RESULTS: 118 DEGs (92 up-regulated and 26 down-regulated) from two GSE datasets were identified, which were closely related with B cell receptor signaling pathway and Epstein-Barr virus infection. Furthermore, CD24 and PTPRC of five hub genes identified in PPI network were further screened out by the logistic regression model. Besides, CD24 and PTPRC expression were significantly correlated to the survival time in MM patients. Finally, MM might cause different infiltrating immune cell compositions, including increased infiltrations of B cells memory, Plasma cells, T cells CD4 memory resting, T cells follicular helper, Tregs, NK cells resting, Macrophages(M0/M1), Dendritic cells resting and Mast cells activating, and lower proportions of B cells naïve, T cells CD4 naïve, Macrophages M2 and Neutrophils. CONCLUSION: Targeting CD24 and PTPRC as molecular markers of MM is valuable to MM therapy. Moreover, the immune cell infiltration will provide new insights into MM immunopathology.


Assuntos
Infecções por Vírus Epstein-Barr , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/genética , Herpesvirus Humano 4 , Plasmócitos , Biologia Computacional
5.
Clin Nurs Res ; 32(2): 433-440, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35699515

RESUMO

To explore the information needs and experiences of patients who underwent Da Vinci robotic surgery and to establish a reference for providing information support to these patients. Semi-structured interviews were conducted with 11 patients who underwent robotic surgery. Thematic analysis was subsequently executed on the data obtained from the interviews to identify the themes. Thematic analysis generated two main themes with six supporting sub-themes. The main themes were (1) surgical information acquisition experience and (2) the need for personalization to obtain satisfactory information. Patients who received Da Vinci robotic surgery had insufficient understanding of the surgical methods and possessed high demand for surgical-related information. Although patients' understanding of robotic surgery might be improved through multi-channel information support, due to the differences in patient access to information, personalized experiences would occur during this process. Professional information support could effectively enhance their positive psychological experiences with surgery.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Pesquisa Qualitativa
6.
J Phys Condens Matter ; 34(41)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35901791

RESUMO

In this paper, a phase-field model of Si-doped hafnium oxide-based ferroelectric thin films is established. And then, the synergistic effect of Si concentration and distribution on ferroelectric properties optimization of Si:HfO2ferroelectric thin films is studied with the proposed model. It is found that no matter how Si dopant is distributed in the film, the volume fraction of the ferroelectric phase in the film increases first and then decreases with the increase of Si concentration. However, compared with the uniform distribution, the layered distribution is more likely to great improve ferrelectric properties. When Si dopant is uniformly distributed in the film, the highest remanent polarization value that the film can obtain via Si concentration modulation is 38.7µC cm-2, and the corresponding Si concentration is 3.8 cat%, which is consistent with the experimental results. When Si dopant is layered in the film, and the concentration difference between the Si-rich and Si-poor layers is 7.6%, in the Si concentration range of 3.6 cat%-3.8 cat%, the residual polarization of the film reaches 46.4-46.8µC cm-2, which is 20% higher than that when Si dopant are evenly distributed in the film. The above results show that selecting the Si layered distribution mode and controlling the concentration difference between Si-rich and Si-poor layers in an appropriate range can greatly improve the films' ferroelectric properties and broaden the Si concentration optimization range of the ferroelectric properties of the films. The result provides further theoretical guidance on using Si doping to adjust the ferroelectric properties of hafnium oxide-based films.

7.
Clin Nurs Res ; 30(7): 1113-1120, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34151607

RESUMO

Coronavirus disease 2019 (COVID-19) has spread rapidly throughout the world. Still, little is known about the psychological experiences of patients who received inpatient isolation treatment in order to improve the well-being of these patients. We randomly recruited 10 COVID-19 patients who received inpatient isolation treatment at a designated hospital in Wuhan from February to March 2020 and were discharged after recovery. The data were collected via a semi-structured interview over WeChat video and analyzed them using Calaizzi's descriptive phenomenological method. COVID-19 patients experienced significant psychological stress during hospitalization that continued after recovery and discharge. This can be categorized into three themes: (1) negative emotions experienced; (2) uncertainty of treatment provided; and (3) worries about readjusting to daily life. The insight into a patient's psychological experiences can support the timely implementation of personalized nursing interventions within hospitals and the community to improve the patient's mental well-being and recovery trajectory.


Assuntos
COVID-19 , Pacientes Internados , Hospitalização , Humanos , Pesquisa Qualitativa , SARS-CoV-2
8.
J Phys Condens Matter ; 33(40)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34265747

RESUMO

Wake-up effect and fatigue in HfO2-based ferroelectric films are closely related to the phase transition dynamics of the film subjected to ultrafast electric pulses. Here, we establish a multiphase coexistence phase field dynamics model for HfO2-based ferroelectric films in the ultrafast time scale and study the effects of the amplitude, width and frequency of the electric pulse on the phase transition dynamics. Based on the simulation results, we obtain the analytical equation of the volume fraction of switchedc-domains under low fields as a function of pulse duration. And we found that monoclinic phase can transform into ferroelectricc-domains under high amplitude electric field (E⩾ 2.8 MV cm-1). The electric pulse duration affects the film's retention properties. When the duration of the electric pulse is less than 1.2 ns or longer than 1.8 ns, the ferroelectricc-domains will respectively invert into other phases or increase cumulatively after removing the electric field. The frequency of cyclic pulse is related to the degree of wake up effect. The lower the pulse frequency is, the more obvious the 'wake up' effect is.

9.
ACS Biomater Sci Eng ; 5(7): 3654-3662, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-33405746

RESUMO

Photothermal therapy (PTT) with the advantages of high efficiency and minimal invasiveness is a promising technique for tumor therapy, but clinical application of PTT agents has been stifled by the great safety concerns. Herein, a deep blue iodine-starch-alginate (ALG) hydrogel is elegantly fabricated based on the classic and simple "iodine-starch test" for in vivo tumor PTT in a facile and mild way. The iodine-starch-ALG hydrogel composed of clinically used agents is fabricated by dispersing blue iodine-starch complex into alginate-Ca2+ hydrogel, which guarantees the good chemical stability of iodine-starch complex via separating them from surrounding reductive environment. The iodine-starch-ALG hydrogel possesses favorable biocompatibility derived from the biosafe and degradable components and possesses good photothermal heating ability based on iodine-starch chromophore. The proposed iodine-starch-ALG hydrogel is successfully applied in tumor PTT in vitro and in vivo for the first time. This work lays down a novel way for the development of high-performance and biocompatible biomaterials via teaching old drugs new tricks.

10.
Exp Ther Med ; 16(3): 2442-2448, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30210596

RESUMO

Patients with chronic kidney disease (CKD) are characterized by a gradual loss of kidney function over time. A number of studies have indicated that tubule interstitial fibrosis (TIF) is associated with the occurrence and development of CKD. The aim of the present study was to investigate the effect of quercetin treatment on the fibrosis of renal tubular epithelial cells and to determine whether the anti-fibrotic effects of quercetin are achieved via microRNA (miR)-21. Human tubular epithelial HK-2 cells were cultured with transforming growth factor (TGF)-ß to induce fibrosis and the expression of fibrotic markers collagen I, fibronectin, α-smooth muscle actin (SMA) and epithelial-cadherin were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Cells were treated with 7.5, 15 or 30 mg/ml quercetin, following which fibrosis and miR-21 expression were evaluated. Quercetin-treated cells were transfected with miR-21 mimics and the expression of fibrotic markers was examined using RT-qPCR. Finally, the expression of fibrosis-associated miR-21 target genes, phosphatase and tensin homolog (PTEN) and TIMP Metallopeptidase Inhibitor 3 (TIMP3), was measured in cells treated with quercetin with or without miR-21 mimics using RT-qPCR, western blotting and immunocytochemistry. The results revealed that TGF-ß treatment induced a significant increase in the expression of fibrotic markers in HK-2 cells, while quercetin treatment partially inhibited the fibrosis of HK-2 cells. Furthermore, quercetin treatment significantly inhibited TGF-ß-induced miR-21 upregulation and transfection with miR-21 mimics reversed the anti-fibrotic effects of quercetin. Quercetin treatment markedly upregulated PTEN and TIMP3 expression, whereas transfection with miR-21 mimics reversed this effect. The results of the present study suggest that quercetin is able to alleviate TGF-ß-induced fibrosis in HK-2 cells via suppressing the miR-21 and upregulating PTEN and TIMP3. Quercetin may have potential as an anti-fibrotic treatment for patients with renal fibrosis.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA