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INTRODUCTION: Asthma is a common chronic respiratory disease characterized by chronic airway inflammation and abnormal airway remodeling. The RhoA/ROCK pathway and myocardin-related transcription factor A (MRTF-A) demonstrate significant associations with the proliferation of airway smooth muscle cells (ASCMs), which tightly correlates with the process of airway remodeling. MYOCD, which is homologous to MRTF-A but specifically expressed in smooth muscle cells, potentially regulates RhoA/ROCK activated cell proliferation and subsequent airway remodeling. METHODS: The RhoA/ROCK overexpression and silencing cell lines were constructed in vitro, as well as MYOCD overexpression/silencing. The cytoskeleton alterations induced by RhoA/ROCK pathway were identified by the measuring of globular actin and filamentous actin. RESULTS: The comparison between controls for overexpression/silencing and ROCK overexpression/silencing revealed that MYOCD presented consistent change trends with cytoskeleton and RhoA/ROCK pathway. The ROCK1 facilitates the proliferation and migration of ASCMs. The MYOCD enhanced the proliferation and migration of HASMCs. CONCLUSION: Our study indicates that Rho/ROCK/MYOCD is a key pathway involved in the migration and proliferation of airway smooth muscle cells. Inhibition of Rho/ROCK may be an effective approach to breaking the vicious cycle of asthmatic ASCMs proliferation, providing a novel strategy in treating asthma airway remodeling.
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Advancements in flexible electronic technology, especially the progress in foldable displays and under-display cameras (UDC), have created an urgent demand for high-performance colorless polyimide (CPI). However, current CPIs lack sufficient heat resistance for substrate applications. In this work, four kinds of rigid spirobifluorene diamines are designed, and the corresponding polyimides are prepared by their condensation with 5,5'-(perfluoropropane-2,2-diyl) bis(isobenzofuran-1,3-dione) (6FDA) or 9,9-bis(3,4-dicarboxyphenyl) fluorene dianhydride (BPAF). The rigid and conjugated spirobifluorene units endow the polyimides with higher glass transition temperature (Tg) ranging from 356 to 468 °C. Their optical properties are regulated by small side groups and spirobifluorene structure with a periodically twisted molecular conformation. Consequently, a series of CPIs with an average transmittance ranging from 75% to 88% and a yellowness index (YI) as low as 2.48 are obtained. Among these, 27SPFTFA-BPAF presents excellent comprehensive performance, with a Tg of 422 °C, a 5 wt.% loss temperature (Td5) of 562 °C, a YI of 3.53, and a tensile strength (δmax) of 140 MPa, respectively. The mechanism underlying the structure-property relationship is investigated by experimental comparison and theoretical calculation, and the proposed method provides a pathway for designing highly rigid conjugated CPIs with excellent thermal stability and transparency for photoelectric engineering.
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Fluorenos , Imidas , Fluorenos/química , Imidas/química , Estructura Molecular , Compuestos de Espiro/química , Temperatura , Polímeros/químicaRESUMEN
Nursing students, who comprise a high percentage of China's college students, experience many psychological problems; however, few studies explored the mechanisms underlying these problems. This cross-sectional study explored the relationships and mechanisms of depression, anxiety, stress, and narrative disorders in senior nursing students. Questionnaires were administered to 380 senior nursing students in Hubei Province using the Sociodemographic Questionnaire, Toronto Alexithymia-20 Scale, Perceived Social Support Scale, 10-Item Connor-Davidson Resilience Scale, and Depression-Anxiety-Stress Scale. After controlling for sociodemographic variables, Hayes' PROCESS macros were used to test how psychological resilience moderates the relationships among narrative disorders, negative affect, and perceived social support. Bootstrap confidence intervals tested for indirect effects. Correlation analyses revealed that alexithymia was correlated significantly positively with depression-anxiety-stress (r = 0.57, 0.56, and 0.58, resp.) and significantly negatively with perceived social support (r = 0-0.46). Psychological resilience was correlated significantly negatively with alexithymia (r=-0.39) and depression-anxiety-stress (r=-0.31, -0.30, and-0.32, resp.) but significantly positively with perceived social support(r = 0.50). Perceived social support was correlated significantly negatively with depression-anxiety-stress (r=-0.33, -0.34, and - 0.42 resp.). Stress was correlated significantly positively with anxiety and depression (r = 0.81 and 0.77, resp.). Psychological resilience was a partial mediator between depression and dysphoria (ß=-0.08, p < 0.05). Dysphoria directly predicted anxiety (ß = 0.31) and stress (ß = 0.37); moreover,alexithymia predicted depression not only directly but also through the mediating effect of psychological resilience. Therefore, educators and clinical administrators must promote and recognise negative emotions among nursing students to help ensure the nursing workforce's stability.
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OBJECTIVES: To investigate the effects and molecular mechanisms of inhibition of the Ras homolog gene (Rho)/Rho-associated coiled-coil forming protein kinase (ROCK) pathway on the proliferation and migration of airway smooth muscle cells involving myocardin (MYOCD). METHODS: Human airway smooth muscle cells were infected with the adenoviral vector Ad-ZsGreen-shRNA-hROCK1 in vitro. The cells were randomly divided into four groups: ROCK1 gene silencing control (shNC) group, shNC + arachidonic acid (AA, Rho/ROCK pathway activator) group, ROCK1 gene silencing (shROCK1) group, and shROCK1 + AA group (n=3 each). Quantitative real-time polymerase chain reaction and Western blot were used to detect the expression levels of ROCK1 and MYOCD mRNA and protein. ELISA was employed to measure the levels of globular actin and filamentous actin, while immunofluorescent staining and scratch assays were utilized to assess cell proliferation and migration. RESULTS: Compared to the shNC + AA group, the shROCK1 + AA group exhibited decreased levels of ROCK1 and MYOCD mRNA and protein expression, reduced expression levels of globular actin and filamentous actin, and diminished cell proliferation and migration capabilities (P<0.05). CONCLUSIONS: Inhibition of the Rho/ROCK pathway suppresses the proliferation and migration of airway smooth muscle cells, which may be associated with the downregulation of MYOCD.
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Movimiento Celular , Proliferación Celular , Miocitos del Músculo Liso , Transducción de Señal , Transactivadores , Quinasas Asociadas a rho , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/fisiología , Quinasas Asociadas a rho/genética , Humanos , Miocitos del Músculo Liso/fisiología , Miocitos del Músculo Liso/metabolismo , Células Cultivadas , Transactivadores/genética , Transactivadores/fisiología , Transactivadores/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Proteínas Nucleares/metabolismo , Proteínas de Unión al GTP rho/fisiología , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismoRESUMEN
In order to demonstrate the formation of laser-induced periodic surface structures (LIPSS), simulations were performed to investigate the effect of multiple femtosecond laser pulses with different laser energy densities on a Ti6Al4V surface. In this work, a set of partial differential equations calculating the electron and lattice temperature variations, followed by coupling with an electric field, is used to analyze the evolution of the periodic surface structure induced by the interaction of the femtosecond laser with the material. As the number of pulses increases, the surface structure of the material changes from none to produce LIPSS structure and from low spatial frequency LIPSS (LSFL) structure to high spatial frequency LIPSS (HSFL) structure. In order to compare the results, single-point laser scanning ablation experiments were carried out at femtosecond laser energy. The experimental results are consistent with the simulation results.
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BACKGROUND: To investigate the baseline data characteristic, human leukocyte antigen (HLA) polymorphisms, and panel reactive antibody (PRA) in end-stage kidney disease (ESKD) patients awaiting kidney transplantation in Southwest China. METHODS: HLA genotyping was performed using the real-time PCR sequence-specific primer. PRA was detected by enzyme-linked immunosorbent assay. The patients' medical records were extracted from the hospital information database. RESULTS: A total of 281 kidney transplant candidates with ESKD were analyzed. The average age was 35.7 ± 13.8 years. There were 61.6% patients had hypertension, 40.2% patients had dialysis ≥ 3 times per week, 47.3% patients had moderate or severe anemia, 30.2% patients with albumin < 35 g/L, 49.1% patients had serum ferritin < 200 ng/mL, 40.5% patients had serum calcium in target range (2.23 - 2.80 mmol/L), 43.4% patients had serum phosphate in target range (1.45 - 2.10 mmol/L), and 93.6% patients with parathyroid hormone > 88.00 pg/mL. In total, 15 HLA-A, 28 HLA-B, 15 HLA-DRB1, and 8 HLA-DQB1 allelic groups were identified. The most frequent alleles for each locus were HLA-A*02 (33.63%), HLA-B*46 (14.41%), HLA-DRB1*15 (21.89%), and HLA-DQB1*05 (39.50%). The most frequent haplotypes were HLA-A*33-B*58-DRB1*17-DQB1*02. A total of 9.60% of patients tested positive for PRAs - Class I or Class II. CONCLUSIONS: The data from this study provide some new insights into baseline data, the distribution of HLA polymorphisms, and PRA results in the population of Southwest China. This is of great significance in this region, and indeed in the country as a whole, in comparison with other populations and in the process of organ transplant allocation.
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Trasplante de Riñón , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Alelos , Cadenas HLA-DRB1 , Haplotipos , ChinaRESUMEN
Heteroaromatic polyimides (PIs) containing benzimidazole have attracted tremendous attention due to their positive impact on the properties of PIs. Some research on PIs containing 4,4'-[5,5'-bi-1H-benzimidazole]-2,2'-diylbis-benzenamine (4-AB) has been reported. However, reports are lacking on homo-polyimides (homo-PIs) containing 3,3'-[5,5'-bi-1H-benzimidazole]-2,2'-diylbis-benzenamine (3-AB), which is one of the isomers of 4-AB. In this paper, the influence of amino groups' positions on the performance of homo-PIs was investigated. It was found that the net charge of the amine N group in 4-AB was lower than that of 3-AB, resulting in higher reactivity of 4-AB. Consequently, PIs containing 4-AB displayed better mechanical performance. Molecular simulation confirmed that 3-AB and its corresponding PI chain exhibited distorted conformation, leading to the PI films containing 3-AB having a lighter color. In addition, the 3-AB structure was calculated to have higher rotational energy compared to 4-AB, resulting in a higher glass transition temperature (Tg) in PIs prepared from 3-AB. On the other hand, PIs containing 4-AB exhibited a higher level of molecular linearity, leading to a lower coefficient of thermal expansion (CTE) compared to PIs prepared from 3-AB. Furthermore, all PIs showed higher thermal stability with a 5% weight loss temperature above 530 °C and Tg higher than 400 °C.
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Compuestos de Anilina , Bencimidazoles , Humanos , Diaminas , FiebreRESUMEN
OBJECTIVES: The prevalence of human papillomavirus (HPV) infection and HPV genotypes varies in different regions. However, there is little data on HPV prevalence and genotyping in Guangxi Province, South China. This study conducted a 10-year survey in a health center, to estimate the prevalence characteristics of HPV genotypes. METHODS: By using polymerase chain reaction (PCR) amplification and nucleic acid molecular hybridization, the HPV genotypes were detected from 77,756 females who were patients of the Department of Obstetrics and Gynecology and those who visited the Health Management Center for a physical examination between August 2011 and November 2020. The prevalence, genotypes, age-related HPV infections, as well as chronological change of HPV prevalence, and the HPV genotype distribution were analyzed. RESULTS: The overall prevalence of HPV infection was 21.14% (16,439/77,756). The HPV infection rate differed significantly between the patients of the Department of Obstetrics and Gynecology and the women who underwent a physical examination (22.98% vs. 9.88%, p < 0.05). The prevalence rates of high-risk HPV, low-risk HPV, mixed HPV (mixed high-risk, and low-risk HPV infection), and multiple HPV infections were 18.96% (14,739/77,756), 4.09% (3178/77,756), 1.90% (1478/77,756), and 4.94% (3838/77,756), respectively. The most prevalent genotypes were HPV 52, 16, and 58. The age-associated HPV prevalence showed bimodal curves, with the first peak at <25 years and the second peak at >56 years. CONCLUSIONS: This study provides baseline data on the HPV prevalence in the general female population of Nanning, Guangxi Province. Women <25 and >56 years old faced the greatest threat of HPV infection, and HPV 52, 16, and 58 were the most common genotypes.
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Alphapapillomavirus , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Adulto , China/epidemiología , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , PrevalenciaRESUMEN
Cell sheet engineering as a cell-based scaffold-free therapy is promising in tissue engineering, allowing precise transforming treatments for various tissue damage. However, the current cutting-edge techniques are still hampered by the difficulty in mimicking the natural tissue organizations and the corresponding physiological functions. In this work, cell-imprinting technology using the natural tissue as a template was proposed to rationally educate the cellular alignment in the cell sheet. Through this technique, we obtained temporary templates with morphological structure complementary to native tissues and then directly transferred the structure on the template to the collagen layer on a photothermally convertible substrate by secondary imprinting replication. The resultant biomimetic interface was used for cell culture and release to obtain a cell sheet with a texture similar to the natural tissue morphology. Different from conventional photolithography, the natural tissue-imprinted biointerface guides the geometry of cell sheets in the way of natural principles instead of stereotyped or overuniform cell organization. Simultaneously, a near-infrared laser (NIR) was used to irradiate the photothermally responsive substrate to obtain complete cell sheets efficiently and nondestructively. The natural tissue-educated myocardium cell sheets exhibited good physiological activity and biomimetic biofunctions, such as mechanical properties and physiological performances. This approach might open an inspiring prospect in regenerative medicine and offer a new approach to realizing the biomimetic tissue construction.
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Biomimética , Ingeniería de Tejidos , Técnicas de Cultivo de Célula/métodos , Colágeno , Miocitos Cardíacos , Ingeniería de Tejidos/métodosRESUMEN
Simulated photoelectron spectroscopy was conducted to investigate the structural evolution and electronic properties of TiASil (A = Sc, Ti; l ≤ 12) clusters and their anions via the Perdew-Burke-Enzerhof scheme and extensive cluster search using the ABCluster software. The results revealed that the ground-state structures of the TiASil (A = Sc, Ti) clusters generally exhibited similar configurations except for the Ti2Si3, ScTiSi3, and TiScSi10 clusters. Furthermore, the TiASil clusters exhibited an adsorptive evolution pattern, and the TiASi4 unit was considered the basic constituent framework of the structure, excluding several distortions and minor changes. With the increase in the cluster size, the lowest-energy structures varied from the exohedral to the cage structures of the single-metal atom at the center. Regarding the second energy difference data, the neutral TiASi4 clusters exhibited better stability among the neutral and anionic TiASil (A = Sc, Ti; l ≤ 12) clusters. Furthermore, the chemical bonding in the TiASi4 clusters was analyzed by molecular orbitals (MOs), highest occupied MO-lowest unoccupied MO gaps, and adaptive natural density partitioning analyses for the best Ti2Si4 cluster especially, and the results were combined with the natural population analysis data. The hybridization of the spd orbital of the metal atoms, eight localized bonds, and four delocalized bonds may primarily account for the relative stabilities of the neutral, square bipyramidal structure of Ti2Si4. Thus, the TiASi4 clusters may be assembled as the basic units of silicon-based semiconductor clusters of large-size neutral and anionic TiASil.
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When performing robotic automatic sorting and assembly operations of multi-category hardware, there are some problems with the existing convolutional neural network visual recognition algorithms, such as large computing power consumption, low recognition efficiency, and a high rate of missed detection and false detection. A novel efficient convolutional neural algorithm for multi-category aliasing hardware recognition is proposed in this paper. On the basis of SSD, the novel algorithm uses Resnet-50 instead of VGG16 as the backbone feature extraction network, and it integrates ECA-Net and Improved Spatial Attention Block (ISAB): two attention mechanisms to improve the ability of learning and extract target features. Then, we pass the weighted features to extra feature layers to build an improved SSD algorithm. At last, in order to compare the performance difference between the novel algorithm and the existing algorithms, three kinds of hardware with different sizes are chosen to constitute an aliasing scene that can simulate an industrial site, and some comparative experiments have been completed finally. The experimental results show that the novel algorithm has an mAP of 98.20% and FPS of 78, which are better than Faster R-CNN, YOLOv4, YOLOXs, EfficientDet-D1, and original SSD in terms of comprehensive performance. The novel algorithm proposed in this paper can improve the efficiency of robotic sorting and assembly of multi-category hardware.
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Algoritmos , Redes Neurales de la Computación , ComputadoresRESUMEN
BACKGROUND: With the COVID-19 outbreak in China, the Chinese government took measures to prevent and control the spread of the virus. In-person teaching was replaced by distance learning, which was an unknown challenge for students. In this context, little is known about the perceived distress of nursing students and the relationship between psychological capital, perceived distress, and psychological stress. This study examined the relationship between psychological capital, psychological distress, and perceived stress, and the mediating role of psychological capital in the relationship between perceived stress and psychological distress among nursing students. METHODS: This cross-sectional survey was conducted between January and December 2020 using a convenience sampling method involving 359 undergraduate and specialist nursing students at a tertiary hospital in Shandong Province. Standardised instruments were used to measure psychological capital, psychological stress, and perceived stress. We used SPSS 24.0 and PROCESS macro to analyse the data. RESULTS: There was a statistically significant difference in perceived stress among students based on whether they liked the nursing profession (P < 0.01). Relative to nursing college students, undergraduates experienced significantly higher levels of perceived stress (P < 0.01). Nevertheless, there were no significant differences in perceived stress according to gender, place of residence, and being an only child. Psychological distress was positively correlated (r = 0.632, p < 0.001) with perceived stress (r =-0.662, p < 0.001), whereas it was negatively correlated with psychological capital. Psychological capital played a potential mediating role in the relationship between psychological distress and perceived stress. CONCLUSIONS: Psychological distress was negatively correlated with psychological capital, and positively correlated with perceived stress. Mediation analyses indicated that psychological capital partially mediated the relationship between perceived stress and psychological distress. Educators should therefore heed students' perceived stress and develop appropriate mental health counselling programmes for students in the curriculum that could help them reduce their psychological distress. In clinical practice, nursing managers must take effective measures, such as skills training, to improve the psychological capital of nursing students and reduce the negative impact of their psychological distress.
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BACKGROUND: Nursing handovers are a critical component of patient safety. Researchers have performed many primary studies in this field, mainly reporting findings from changes in nursing handover patterns. However, few quantitative studies have explored the factors that influence handover quality. Therefore, this study aimed to investigate the quality of handovers and explore the associations between handover quality, job satisfaction, and group cohesion among psychiatric nurses. METHODS: This cross-sectional study included 186 registered psychiatric nurses from a Chinese hospital, who responded to the Handover Evaluation Scale, McCloskey/Mueller Satisfaction Scale, and Group Cohesion Scale. Bootstrap analyses were used to evaluate the mediating effect between variables. RESULTS: The average item score for handover quality was (5.85 ± 1.14), and job satisfaction and group cohesion could predict the variance of handover quality. Job satisfaction could partially mediate between group cohesion and handover quality, and the value of the mediating effect was 45.77%. CONCLUSION: The quality of psychiatric nursing handovers has enhanced space. Thus, hospital managers should take various measures to strengthen group cohesion and promote job satisfaction, both of which help improve the quality of psychiatric nursing handovers.
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Protein deglycase DJ-1 (DJ-1) is a multifunctional protein involved in various biological processes. However, it is unclear whether DJ-1 influences atherosclerosis development and plaque stability. Accordingly, we evaluated the influence of DJ-1 deletion on the progression of atherosclerosis and elucidate the underlying mechanisms. We examine the expression of DJ-1 in atherosclerotic plaques of human and mouse models which showed that DJ-1 expression was significantly decreased in human plaques compared with that in healthy vessels. Consistent with this, the DJ-1 levels were persistently reduced in atherosclerotic lesions of ApoE-/- mice with the increasing time fed by western diet. Furthermore, exposure of vascular smooth muscle cells (VSMCs) to oxidized low-density lipoprotein down-regulated DJ-1 in vitro. The canonical markers of plaque stability and VSMC phenotypes were evaluated in vivo and in vitro. DJ-1 deficiency in Apoe-/- mice promoted the progression of atherosclerosis and exaggerated plaque instability. Moreover, isolated VSMCs from Apoe-/- DJ-1-/- mice showed lower expression of contractile markers (α-smooth muscle actin and calponin) and higher expression of synthetic indicators (osteopontin, vimentin and tropoelastin) and Kruppel-like factor 4 (KLF4) by comparison with Apoe-/- DJ-1+/+ mice. Furthermore, genetic inhibition of KLF4 counteracted the adverse effects of DJ-1 deletion. Therefore, our results showed that DJ-1 deletion caused phenotype switching of VSMCs and exacerbated atherosclerotic plaque instability in a KLF4-dependent manner.
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Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Placa Aterosclerótica/etiología , Placa Aterosclerótica/metabolismo , Proteína Desglicasa DJ-1/deficiencia , Animales , Apolipoproteínas E/deficiencia , Biomarcadores , Biopsia , Arterias Carótidas/metabolismo , Arterias Carótidas/patología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Lipoproteínas LDL/metabolismo , Ratones , Ratones Noqueados , Modelos Biológicos , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Fenotipo , Placa Aterosclerótica/patología , Transducción de SeñalRESUMEN
Fatty liver disease associated with metabolic dysfunction is of increasing concern in mainland China, the world's most populous country. The incidence of fatty liver disease is highest in China, surpassing the incidence in European countries and the USA. An international consensus panel recently published an influential report recommending a novel definition of fatty liver disease associated with metabolic dysfunction. This recommendation includes a switch in name from non-alcoholic fatty liver disease (NAFLD) to metabolic (dysfunction)-associated fatty liver disease (MAFLD) and adoption of a set of positive criteria for disease diagnosis that are independent of alcohol intake or other liver diseases. Given the unique importance of this proposal, the Chinese Society of Hepatology (CSH) invited leading hepatologists and gastroenterologists representing their respective provinces and cities to reach consensus on alternative definitions for fatty liver disease from a national perspective. The CSH endorses the proposed change from NAFLD to MAFLD (supported by 95.45% of participants). We expect that the new definition will result in substantial improvements in health care for patients and advance disease awareness, public health policy, and political, scientific and funding outcomes for MAFLD in China.
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Hígado Graso/fisiopatología , Gastroenterología/tendencias , China , Hígado Graso/clasificación , Gastroenterología/organización & administración , HumanosRESUMEN
The growth patterns, simulated photoelectron spectra, and electronic properties of LaASil (A = Sc, Y, and La; l ≤ 10) compounds and their anions were studied via quantum chemistry calculations using the Perdew-Burke-Ernzerhof (PBE) method and unprejudiced structural searching software ABCluster. The results revealed that the growth patterns of the most stable structures of neutral and anionic LaASil showed an adsorptive mode. The lowest-energy structures (LESs) of the LaASil (l ≤ 7) clusters were similar, except for those of anionic LaYSi4- and LaYSi5- and neutral LaScSi7. Additionally, we investigated and calculated the photoelectron spectra, vertical detachment energies, adiabatic electron affinities, relative stability, charge transfer, magnetic moment, and chemical bond analysis of the LaASil ground-state structures. The La2Sil clusters exhibited higher stability than the LaYSil and LaScSil systems owing to their higher dissociation energies (DEs). The DEs of the LESs in the LaASi3 molecule are higher than those of other clusters. Thus, the LaASi3 cluster shows potential as a building framework for Si-based cluster materials with good stability. The natural population analysis data and chemical bond analysis results showed that the spd hybridization of the orbitals of the metal atoms in the LaASil system occurred. Except for the LaScSi9 and LaScSi10 clusters, the neutral LaASil compounds transform into the corresponding anions when an extra electron is accepted by the Si clusters.
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AIM: The present study aimed to assess the benefits of two-stent techniques for patients with DEFINITION criteria-defined complex coronary bifurcation lesions. METHODS AND RESULTS: In total, 653 patients with complex bifurcation lesions at 49 international centres were randomly assigned to undergo the systematic two-stent technique (two-stent group) or provisional stenting (provisional group). The primary endpoint was the composite of target lesion failure (TLF) at the 1-year follow-up, including cardiac death, target vessel myocardial infarction (TVMI), and clinically driven target lesion revascularization (TLR). The safety endpoint was definite or probable stent thrombosis. At the 1-year follow-up, TLF occurred in 37 (11.4%) and 20 (6.1%) patients in the provisional and two-stent groups, respectively [77.8%: double-kissing crush; hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.30-0.90; P = 0.019], largely driven by increased TVMI (7.1%, HR 0.43, 95% CI 0.20-0.90; P = 0.025) and clinically driven TLR (5.5%, HR 0.43, 95% CI 0.19-1.00; P = 0.049) in the provisional group. At the 1 year after indexed procedures, the incidence of cardiac death was 2.5% in the provisional group, non-significant to 2.1% in the two-stent group (HR 0.86, 95% CI 0.31-2.37; P = 0.772). CONCLUSION: For DEFINITION criteria-defined complex coronary bifurcation lesions, the systematic two-stent approach was associated with a significant improvement in clinical outcomes compared with the provisional stenting approach. Further study is urgently warranted to identify the mechanisms contributing to the increased rate of TVMI after provisional stenting. STUDY REGISTRATION: http://www.clinicaltrials.com; Identifier: NCT02284750.
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Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Stents , Factores de Tiempo , Resultado del TratamientoRESUMEN
The spiral is a fundamental structure in nature and spiral structures with controllable handedness are of increasing interest in the design of new chiroptical materials. In this study, micrometer-scale spiral structures with reversible chirality were fabricated based on the assembly of a liquid crystalline block copolymer film assisted by enantiopure tartaric acid. Mechanistic insight revealed that the formation of the spiral structures was closely related to the liquid crystalline properties of the major phase of block copolymer under the action of chiral tartaric acid. The chiral spiral structures with controllable handedness were easily erased under ultraviolet light irradiation and restored via thermal annealing. This facile thermal treatment method provides guidance for fabrication of chiral micrometer-scale spiral structures with adjustable chiral properties.
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Cardiovascular magnetic resonance imaging has proven valuable for the assessment of structural and functional cardiac abnormalities. Even although it is an established imaging method in small animals, the long acquisition times of gated or self-gated techniques still limit its widespread application. In this study, the application of tiny golden angle radial sparse MRI (tyGRASP) for real-time cardiac imaging was tested in 12 constitutive nexilin (Nexn) knock-out (KO) mice, both heterozygous (Het, N = 6) and wild-type (WT, N = 6), and the resulting functional parameters were compared with a well-established self-gating approach. Real-time images were reconstructed for different temporal resolutions of between 16.8 and 79.8 ms per image. The suggested approach was additionally tested for dobutamine stress and qualitative first-pass perfusion imaging. Measurements were repeated twice within 2 weeks for reproducibility assessment. In direct comparison with the high-quality, self-gated technique, the real-time approach did not show any significant differences in global function parameters for acquisition times below 50 ms (rest) and 31.5 ms (stress). Compared with WT, the end-diastolic volume (EDV) and end-systolic volume (ESV) were markedly higher (P < 0.05) and the ejection fraction (EF) was significantly lower in the Het Nexn-KO mice at rest (P < 0.001). For the stress investigation, a clear decrease of EDV and ESV, and an increase in EF, but maintained stroke volume, could be observed in both groups. Combined with ECG-triggering, tyGRASP provided first-pass perfusion data with a temporal resolution of one image per heartbeat, allowing the quantitative assessment of upslope curves in the blood-pool and myocardium. Excellent inter-study reproducibility was achieved in all the functional parameters. The tyGRASP is a valuable real-time MRI technique for mice, which significantly reduces the scan time in preclinical cardiac functional imaging, providing sufficient image quality for deriving accurate functional parameters, and has the potential to investigate real-time and beat-to-beat changes.
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Algoritmos , Corazón/diagnóstico por imagen , Imagen por Resonancia Magnética , Animales , Estudios de Factibilidad , Femenino , Masculino , Ratones Noqueados , Perfusión , Reproducibilidad de los Resultados , Descanso/fisiología , Estrés Fisiológico , Factores de Tiempo , Función Ventricular Izquierda/fisiologíaRESUMEN
The acoustic emission (AE) signal collected by a sensor in the welding process has an overlapping frequency band and weak characteristics under a complex noise background. It is difficult for the wavelet noise reduction method, with single basis function, to effectively match the different characteristic information of the welding crack AE signal. Taking into account the adaptive decomposition characteristics of Empirical Mode Decomposition (EMD), a novel wavelet packet noise reduction method for welding AE signal was proposed. The welding AE signal was adaptively decomposed into several Intrinsic Mode Functions (IMFs) by the EMD. The effective IMFs were selected by the frequency distribution characteristics of the welding crack AE signal. A wavelet packet, with a specific basis function, was subsequently performed on the effective IMFs, which were reconstructed to be the welding crack AE signal. The simulated and experimental results indicated that the proposed method can effectively achieve noise reduction of the welding crack AE signal, which provided a mean for structure crack detection in the welding process.