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1.
Nano Lett ; 24(29): 8979-8987, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38994924

RESUMEN

With the development of miniaturized devices, there is an increasing demand for 2D multifunctional materials. Six ferroelastic semiconductors, Y2Se2XX' (X, X' = I, Br, Cl, or F; X ≠ X') monolayers, are theoretically predicted here. Their in-plane anisotropic band structure, elastic and piezoelectric properties can be switched by ferroelastic strain. Moderate energy barriers can prevent the undesired ferroelastic switching that minor interferences produce. These monolayers exhibit high carrier mobilities (up to 104 cm2 V-1 s-1) with strong in-plane anisotropy. Furthermore, their wide bandgaps and high potential differences make them broad-pH-value and high-performance photocatalysts at pH value of 0-14. Strikingly, Y2Se2BrF possesses outstanding d33 (d33 = -405.97 pm/V), greatly outperforming CuInP2S6 by 4.26 times. Overall, the nano Y2Se2BrF is a hopeful candidate for multifunctional devices to generate a direct current and achieve solar-free photocatalysis. This work provides a new paradigm for the design of multifunctional energy materials.

2.
Immunology ; 172(3): 469-485, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38544333

RESUMEN

Endometriosis is defined as an oestrogen-dependent and inflammatory gynaecological disease of which the pathogenesis remains unclear. This study aimed to investigate the cellular heterogeneity and reveal the effect of CD8+ T cells on the progress of endometriosis. Three ovarian endometriosis patients were collected, and single-cell RNA sequencing (scRNA-seq) progressed and delineated the cellular landscape of endometriosis containing five cell clusters. The endometrial cells (EMCs) were the major component, of which the mesenchymal cells were preponderant and characterized with increased inflammation and oestrogen synthesis in endometriosis. The proportion of T cells, mainly CD8+ T cells rather than CD4+, was reduced in endometriotic lesions, and the cytokines and cytotoxicity of ectopic T cells were depressed. CD8+ T cells depressed the proliferation of ESCs through inhibiting CDK1/CCNB1 pathway to arrest the cell cycle and triggered inflammation through activating STAT1 pathway. Correspondingly, the coculture with ESCs resulted in the dysfunction of CD8+ T cells through upregulating STAT1/PDCD1 pathway and glycolysis-promoted metabolism reprogramming. The endometriotic lesions were larger in nude mouse models with T-cell deficiency than the normal mouse models. The inhibition of T cells via CD90.2 or CD8A antibody increased the endometriotic lesions in mouse models, and the supplement of T cells to nude mouse models diminished the lesion sizes. In conclusion, this study revealed the global cellular variation of endometriosis among which the cellular count and physiology of EMCs and T cells were significantly changed. The depressed cytotoxicity and aberrant metabolism of CD8+ T cells were induced by ESCs with the activation of STAT1/PDCD1 pathway resulting in immune survival to promote endometriosis.


Asunto(s)
Linfocitos T CD8-positivos , Endometriosis , Factor de Transcripción STAT1 , Células del Estroma , Endometriosis/inmunología , Endometriosis/patología , Endometriosis/metabolismo , Femenino , Linfocitos T CD8-positivos/inmunología , Humanos , Animales , Ratones , Células del Estroma/inmunología , Células del Estroma/metabolismo , Factor de Transcripción STAT1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Endometrio/inmunología , Endometrio/patología , Modelos Animales de Enfermedad , Transducción de Señal , Ratones Desnudos , Adulto , Proteína Quinasa CDC2/metabolismo , Técnicas de Cocultivo , Citocinas/metabolismo
3.
Gen Thorac Cardiovasc Surg ; 72(5): 355-358, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38261229

RESUMEN

Acute type A aortic dissection may originate from a primary intimal tear located in the ascending aorta and often extends retrogradely into the aortic root. How to prevent bleeding in the aortic root and eliminate false lumen is very important in aortic dissection. We have developed a modified anastomotic technique that involves inverting adventitial and graft into aorta and reinforcing with a felt strip on the external border of the aortic wall. Since 2020, 45 consecutive patients with type A aortic coarctation have undergone this aortic root reconstruction procedure, to date, none have been reopened for bleeding or remnant dissection.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Humanos , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía , Aorta/cirugía , Aneurisma de la Aorta Torácica/cirugía
4.
Nano Lett ; 23(21): 10013-10020, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37856232

RESUMEN

The realization of multiferroic materials offers the possibility of multifunctional electronic device design. However, the coupling between the multiferroicity and piezoelectricity in Janus materials is rarely reported. In this study, we propose a mechanism for manipulating valley physics by magnetization reversing and ferroelectric switching in multiferroic and piezoelectric material. The ferromagnetic VSiGeP4 monolayer exhibits a large valley polarization up to 100 meV, which can be effectively operated by reversing magnetization. Interestingly, the antiferromagnetic VSiGeP4 bilayers with AB and BA stacking configurations allow the coexistence of valley polarization and ferroelectricity, supporting the proposed strategy for manipulating valley physics via ferroelectric switching and interlayer sliding. In addition, the VSiGeP4 monolayer contains remarkable tunable piezoelectricity regulated by electron correlation U. This study proposes a feasible idea for regulating valley polarization and a general design idea for multifunctional devices with multiferroic and piezoelectric properties, facilitating the miniaturization and integration of nanodevices.

5.
Nanoscale ; 15(24): 10458-10464, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37309617

RESUMEN

Two-dimensional photocatalytic materials with unique properties have been well-reported in recent decades. However, strategies for controlling the photocatalytic process are still ongoing. Herein, Janus X2PAs (X = Si, Ge and Sn) monolayers have been explored by first-principles calculations to meet this challenge. All strain-free X2PAs monolayers exhibit excellent photocatalytic properties with high carrier mobility (2.39 × 102-1.34 × 104 cm2 V-1 s-1), suitable band edge positions straddling the standard redox potential of water and large visible light absorption coefficients (up to 105 cm-1). Most importantly, a reaction switch effect is proposed for the first time towards controlling the microscopic photocatalytic process of water splitting on X2PAs monolayers through macroscopic mechanical strain. This effect renders the Janus X2PAs photocatalytic switches among the states of only oxygen evolution reaction, only hydrogen evolution reaction and the full redox reaction for controlled water splitting. This work not only provides a new avenue for designing highly tunable photocatalysts but also offers new physical insights into controlling the photocatalytic water-splitting reaction.


Asunto(s)
Excipientes , Hidrógeno , Oxígeno , Agua
6.
J Glob Health ; 13: 06012, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37058575

RESUMEN

Background: Obesity is an independent risk factor for severe coronavirus disease 2019 (COVID-19), but there is little evidence on whether prior bariatric surgery benefits the outcomes of patients with COVID-19. We aimed to summarize this relationship by conducting a systematic review and meta-analysis of current case-control studies. Methods: We searched several electronic databases for case-control studies conducted between January 2020 and March 2022. We compared the rates of mortality, mechanical ventilation, intensive care unit (ICU) admission, dialysis, hospitalization, and length of hospital stay between COVID-19 patients with and without a history of bariatric surgery. Results: We included six studies with 137 903 patients; 5270 (3.8%) had prior bariatric surgery, while 132 633 (96.2%) did not. COVID-19 patients with a history of bariatric surgery had significantly lower mortality (odds ratio (OR) = 0.42; 95% confidence interval (CI) = 0.23-0.74), ICU admission (OR = 0.48; 95% CI = 0.36-0.65), and mechanical ventilation rates than those with a history of non-bariatric surgery (OR = 0.51; 95% CI = 0.35-0.75). Conclusions: Prior bariatric surgery was associated with a reduced risk of mortality and reduced severity of COVID-19 in patients with obesity compared to those with no prior bariatric surgery. Further large-sample prospective studies are needed to support these results. Registration: CRD42022323745.


Asunto(s)
Cirugía Bariátrica , COVID-19 , Humanos , Cirugía Bariátrica/efectos adversos , Cirugía Bariátrica/métodos , Hospitalización , Obesidad/complicaciones , Obesidad/epidemiología , Estudios de Casos y Controles
7.
J Phys Condens Matter ; 35(29)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37059113

RESUMEN

It is well known that the traditional two-dimensional electron system (2DES) hosted by the SrTiO3substrate can exhibit diverse electronic states by modifying the capping layer in heterostructures. However, such capping layer engineering is less studied in the SrTiO3-layer-carried 2DES (or bilayer 2DES), which is different from the traditional one on transport properties but more applicable to the thin-film devices. Here, several SrTiO3bilayers are fabricated by growing various crystalline and amorphous oxide capping layers on the epitaxial SrTiO3layers. For the crystalline bilayer 2DES, the monotonical reduction on the interfacial conductance, as well as carrier mobility, is recorded on increasing the lattice mismatch between the capping layers and epitaxial SrTiO3layer. The mobility edge raised by the interfacial disorders is highlighted in the crystalline bilayer 2DES. On the other hand, when increasing the concentration of Al with high oxygen affinity in the capping layer, the amorphous bilayer 2DES becomes more conductive accompanied by the enhanced carrier mobility but almost constant carrier density. This observation cannot be explained by the simple redox-reaction model, and the interfacial charge screening and band bending need to be considered. Moreover, when the capping oxide layers have the same chemical composition but with different forms, the crystalline 2DES with a large lattice mismatch is more insulating than its amorphous counterpart, and vice versa. Our results shed some light on understanding the different dominant role in forming the bilayer 2DES using crystalline and amorphous oxide capping layer, which may be applicable in designing other functional oxide interfaces.

8.
J Physiol Biochem ; 79(3): 569-582, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36905457

RESUMEN

The Roux-en-Y gastric bypass (RYGB) is a one-of-a-kind treatment among contemporary bariatric surgical procedures, and its therapeutic effects for type 2 diabetes mellitus (T2DM) are satisfactory. The present study performed isobaric tags for relative and absolute quantification (iTRAQ) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis identifying different proteomics between T2DM rats with or without Roux-en-Y gastric bypass (RYGB) surgery, and GTP binding elongation factor GUF1 (Guf1) was first found to be significantly upregulated in rats from the T2DM plus RYGB group. In the cellular lipotoxicity model induced by palmitic acid stimulation of rat pancreatic beta cell line, INS-1, palmitic acid treatment inhibited cell viability, suppressed GSIS, promoted lipid droplet formation, promoted cell apoptosis, and induced mitochondrial membrane potential loss. The effects of palmitic acid on INS-1 cells mentioned above could be partially eliminated by Guf1 overexpression but aggravated by Guf1 knockdown. Last, under palmitic acid treatment, Guf1 overexpression promotes the PI3K/Akt and NF-κB signaling but inhibits the AMPK activation. Guf1 is upregulated in T2DM rats who received RYGB, and Guf1 overexpression improves cell mitochondrial functions, increases cell proliferation, inhibits cell apoptosis, and promotes cell functions in palmitic acid-treated ß cells.


Asunto(s)
Diabetes Mellitus Tipo 2 , Derivación Gástrica , Células Secretoras de Insulina , Ratas , Animales , Diabetes Mellitus Tipo 2/cirugía , Diabetes Mellitus Tipo 2/metabolismo , Derivación Gástrica/métodos , Células Secretoras de Insulina/metabolismo , Cromatografía Liquida , Ácido Palmítico , Fosfatidilinositol 3-Quinasas , Espectrometría de Masas en Tándem
9.
Inorg Chem ; 61(48): 19399-19406, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36383555

RESUMEN

The epitaxial (K0.49Na0.49Li0.02)(Ta0.2Nb0.8)O3 with 2 wt % MnO2 addition (KNNLT-M) film on the transparent La0.03Ba0.97SnO3-coated LaAlO3 (001) substrate is chosen to investigate how the lattice evolution, as well as the electrical properties, optical bandgap energy, and thermal stability, changes with the growth oxygen pressure [P(O2)]. Compared to the other perovskite oxide films, for example, (La,Ca)MnO3, PbTiO3, and BaTiO3, an anomalous lattice evolution with an increased (decreased) out-of-plane (in-plane) lattice constant was observed in KNNLT-M films as P(O2) increases. Such anomalous lattice evolution can improve the electric properties of KNNLT-M films; for example, the ferroelectricity is significantly optimized and the dielectric constant is enhanced from 451 to 1248 at 1 kHz. The X-ray photoelectron spectra results have demonstrated that high P(O2) can make more K cations to enter the perovskite lattice and the Mn2+/Mn3+ existing in KNNLT can effectively suppress the leakage behavior, thus promoting the electrical nature of KNNLT-M films. The optical measurements show that the KNNLT-M film heterostructures are highly transparent with a maximum transmittance of ∼80%, and both direct and indirect bandgap energies increase with increasing P(O2). Meanwhile, all these KNNLT-M films exhibit good thermal stability with stable ferroelectricity up to the high temperature of at least 125 °C. These results demonstrate that the control of the lattice structure and electrical properties by P(O2) is one of the important prerequisites for the application of KNN-based films.

10.
J Phys Chem Lett ; 13(41): 9654-9663, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36214516

RESUMEN

Development of piezoelectric materials is limited partly due to the incompleteness of internal mechanism and the lack of vertical piezoelectricity. Herein, we theoretically identify the stable MoTO (T = S, Se, or Te) monolayers and bilayers. When two elements are given but another element can be changed, the larger the electronegativity difference ratio Rratio is, the stronger the piezoelectricity will be. Vertical piezoelectric coefficient d33 of the MoTeO bilayer reaches 38.907 pm/V, which is 12 times larger than that of the bulk GaN. The "active asymmetric electron-transfer" strategy mainly contributes to the spontaneous remarkable piezoelectricity of MoTO. Importantly, we proposed the new method for calculating the piezoelectric coefficients of two-dimensional (2D) materials, which corresponds to the fact that 2D materials have a certain thickness. This study not only provides novel extraordinary candidates for energy conversion and touch-sensor nanodevices but also promotes a deeper understanding of piezoelectricity of 2D materials.

11.
Front Endocrinol (Lausanne) ; 13: 913062, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36120423

RESUMEN

Background: Roux-en-Y gastric bypass (RYGB) results in extraordinary weight loss and glycemic control outcomes for patients with obesity; however, the effect of gastric pouch size is still unclear, and the reported results are contradictory. Additionally, long-term data on type 2 diabetes (T2D) patients with low body mass index (BMI) are sparse. This study was to assess the effect of 6-year outcomes in Chinese patients with T2D and a BMI < 35 kg/m2 who underwent RYGB with gastric pouches of different sizes. Methods: A retrospective cohort study was performed. There were 42 patients in the large gastric pouch group (L) and 53 patients in the small gastric pouch group (S). Baseline demographic history, pre- and postoperative BMI, waist circumference, and glucose- and lipid metabolism-related indicators were compared. Results: Assessments were completed in 100%, 100%, 93.6%, and 89.4% of patients at baseline, 1 year, 3 years, and 6 years, respectively. At 6 years, the changes in BMI and fasting plasma glucose were greater in the S group (-4.25 ± 0.51 kg/m2 and -4.58 ± 0.73 mmol/l) than in the L group (-2.06 ± 0.48 kg/m2 and -2.64 ± 0.61 mmol/l). The independent predictors of complete remission of T2D were preoperative BMI and the size of the gastric pouch. A large gastric pouch was associated with a higher risk for marginal ulcers. Conclusions: A small gastric pouch results in better weight loss and glycemic control. High preoperative BMI and a small gastric pouch are associated with better T2D remission rates. A large gastric pouch leads to a higher incidence of marginal ulcers.


Asunto(s)
Diabetes Mellitus Tipo 2 , Derivación Gástrica , Úlcera Péptica , Glucemia , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/cirugía , Derivación Gástrica/métodos , Humanos , Úlcera Péptica/complicaciones , Estudios Retrospectivos , Pérdida de Peso
12.
Phys Chem Chem Phys ; 24(39): 24264-24270, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36172737

RESUMEN

The oxidation of methane to a high-value-added chemical, methanol, is a major challenge in catalysis, requiring high energy input to overcome the CH3-H bond activation energy barrier. Based on density functional theory (DFT) calculations, methane oxidation to methanol is catalyzed by hetero-diatomic catalysts (CuZn-NG) with different coordination spheres (CSs). Valence band maximum (VBM), atomic charge and d-band center are selected as analysis methods for the pathway selection and activity of catalysis. The VBM plays a vital role in the catalytic pathway selection, CuZn-NG catalyzes the direct conversion of methane into methanol without side reactions. Alarmingly, the most important reaction step, CH3-H bond activation, is a spontaneously exothermic reaction (releasing 0.06 eV) with CuZn-NPAG as the catalyst, in contrast to most other endothermic reactions in the same activation. By analyzing the atomic charge of the Cu center and O atom, the special electronic phenomenon for this important step is summarized as the "bow-release effect". The CS affects the electronic properties of the active center and further affects the methane oxidation activity. This work provides a useful guide to understand the catalytic selectivity and activity of hetero-diatomic catalysts.

13.
Oncogene ; 41(1): 99-111, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34697449

RESUMEN

The long non-coding RNA (lncRNA), HOX antisense intergenic RNA (HOTAIR) is a well-characterized oncogene in multiple human cancers, but not in cutaneous squamous cell carcinoma (CSCC). In this study, we focused on investigating the potential role of HOTAIR in stemness of CSCC. By measuring its expression using RT-qPCR in CSCC vs. normal tissues, as well as in CSCC cell lines A431 or SCC13, A431- or SCC13-derived CSCC stem cells (CSCSCs), and normal skin fibroblasts (HSFs), we detected higher expression of HOTAIR in CSCC than in normal tissues, in recurrent than in non-recurrent CSCC tissues, in CSCCs and CSCSCs than in HSFs, and particularly, in CSCSCs than in CSCCs. Kaplan-Meier analysis suggested that higher expression of HOTAIR was positively correlated with worse overall survival of CSCC patients. Functional assays on colony formation, EdU incorporation, sphere formation, western blot on stem-cell biomarkers, and in vivo models showed that HOTAIR was essential in maintaining multiple stem cell phenotypes of CSCSCs in vitro and in vivo xenograft growth as well as metastasis. Mechanistically, HOTAIR directly interacted with and up-regulated Sp1. Sp1 then induced DNMT1-mediated promoter methylation and direct transcriptional repression of miR-199a-5p. Targeting Sp1 or DNMT1 further boosted the in vivo anti-tumor and anti-metastasis activities of targeting HOTAIR. In conclusion, HOTAIR, by up-regulating Sp1 and targeting miR-199a, promotes stemness and progression of CSCC. Targeting HOTAIR, Sp1 or the underlying mechanisms may thus benefit CSCC treatment.


Asunto(s)
Carcinoma de Células Escamosas/genética , MicroARNs/metabolismo , Células Madre Neoplásicas/metabolismo , ARN Largo no Codificante/metabolismo , Neoplasias Cutáneas/genética , Animales , Carcinoma de Células Escamosas/mortalidad , Progresión de la Enfermedad , Humanos , Ratones , Ratones Desnudos , Neoplasias Cutáneas/mortalidad , Análisis de Supervivencia
14.
Plant Methods ; 17(1): 55, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34034763

RESUMEN

BACKGROUND: Water uptake is essential for seed germination. However, Gleditsia sinensis seeds have a water-impermeable seed coat, which is beneficial for its adaption to the environment, but prohibits its germination without treatment. This feature may be associated with the structure of the seed coat. Thus, the aim of this research was to identify and describe the initial water uptake site and water movement and to determine the relationship between seed coat structure and water absorption. RESULTS: A water temperature of 80 °C was optimal to break the hardseededness of G. sinensis seeds. Scanning electron microscopy (SEM) images revealed that the seed coat consisted of a palisade layer and light line that can hinder water entry into the seed. Also, a structure of vascular bundles existed in the hilar region. Hot water treatment caused the tightly closed micropyle to open and the cavity beneath it expanded; the layer of palisade cells in the lens was raised. The embryo dye-tracking tests showed that the radicle tip was the initial region to be stained red. After staining for 24 h, the red-stained area on the vascular bundle side of cotyledon was more extensive than that on the other side. Further studies by MRI maps indicated that the micropyle was the initial site for water imbibition. Some water then migrated along the space between the seed coat and the endosperm to the chalazal; simultaneously, the rest of the water reached the embryonic axis and spread into cotyledons. The maps of 20-24 h showed that water was unevenly distributed within the cotyledons in a way that the edge parts were more hydrated than the center. Blocking tests showed that the hilar region was the initial and an important region during seed imbibition. The medial region and chalazal portion were capable of imbibing water when the hilar region was blocked, but water absorption was later and slower than that through the hilar region. CONCLUSION: MRI technology provides a promising and non-invasive technique to identify the water gap and the path of water movement in the seed. Combined with the results of SEM, the relation between seed coat and its imbibition can be inferred.

15.
Pain Ther ; 10(1): 525-538, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33616874

RESUMEN

INTRODUCTION: Postoperative pain management is an essential module for perioperative care, especially for enhanced recovery after surgery programs. Continuous wound infiltration (CWI) with local anesthetic may be a promising postoperative analgesic strategy. However, its analgesic efficacy and safety remain debatable. METHODS: Embase and PubMed databases were systematically searched for relevant randomized controlled trials (RCTs). RCTs assessing the analgesic efficacy and safety of CWI with local anesthetic for postoperative analgesia were selected. The outcomes contained pain scores during rest and mobilization, total opioid consumption, time to the first request of rescue analgesia, length of hospital stay, satisfaction with analgesia, time to return of bowel function, postoperative nausea and vomiting, total complication, wound infection, hypotension, and pruritus. The weighted mean difference and risk ratio were used to pool continuous and dichotomous variables, respectively. RESULTS: A total of 121 RCTs were included. CWI with local anesthetic reduced postoperative pain during rest and mobilization at different time points, increased satisfaction with analgesia, shortened recovery of bowel function, and reduced postoperative nausea and vomiting compared with the placebo group, especially for laparotomy surgery. There were no significant differences in these clinical outcomes compared to epidural and intravenous analgesia. CWI with local anesthetic reduced the total opioid consumption and hypotension risk and did not increase total complications, wound infection, or pruritus. CWI with local anesthetic had a better analgesic efficacy without increased side effects for sternotomy surgery. However, CWI with local anesthetic did not translate into favorable analgesic benefits in laparoscopic surgery. CONCLUSION: CWI with local anesthetic is an effective postoperative analgesic strategy with good safety profiles in laparotomy and sternotomy surgery, and thus CWI with local anesthetic may be a promising analgesic option enhancing recovery after surgery programs for these surgeries.


Continuous wound infiltration (CWI) with local anesthetic may be a promising postoperative analgesic strategy, but its effect remains debatable. We performed this meta-analysis based on 121 high-quality articles (RCTs) to evaluate the analgesic efficacy and safety of CWI with local anesthetic. We found that CWI with local anesthetic could reduce postoperative pain, increase satisfaction with analgesia, shorten recovery of bowel function, and reduce postoperative nausea and vomiting, especially for laparotomy surgery. However, CWI with local anesthetic did not show favorable analgesic benefits in laparoscopic surgery.

16.
Inorg Chem ; 60(2): 995-1006, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33390011

RESUMEN

In this study, three different Ga-containing systems based on GaCl3, Ga2Cl6, or ionic [Ga(L)3][GaCl4]3 (L = methylidenemalonate) complex were screened to elucidate the mechanism, regioselectivity, chemoselectivity, and role of Ga mediator in the reaction between two types of acetylenes (phenylacetylene and but-1-yn-1-ylbenzene) and methylidenemalonates, i.e., the 1,2-zwitterionic precursors that are similar to intermediates derived from donor-acceptor cyclopropanes (DACs). Our DFT calculation results clearly show that the ionic gallium complex [Ga(L)3][GaCl4]3 represents the key mediator in the title reaction. After the formation of such a complex, the first reaction step is the nucleophilic addition of phenylacetylene or but-1-yn-1-ylbenzene to [Ga(L)3][GaCl4]3, generating an unstable vinyl cation intermediate. In the phenylacetylene system, this vinyl cation intermediate accepts a chlorine atom from [GaCl4]- to give E-configuration intermediate. Then, the above process occurs to other two ligands of the Ga(III) complex to furnish a final product. On the other hand, in the but-1-yn-1-ylbenzene system, the vinyl cation intermediate prefers to undergo Friedel-Crafts (F-C) alkylation to generate a five-membered ring intermediate. This process is repeated on the other two methylidenemalonate ligands, giving rise to a final cyclization product. The distortion/interaction analysis shows that in the nucleophilic addition step the distortion energy of the Ga complex part is the main factor that influences the activation energy. Furthermore, the global reactivity index (GRI) analysis indicates that the Ga-complex model has the highest electrophilicity index ω, thus leading to the lowest energy barrier among three Ga-based models. In addition, DFT results reveal that the regioselectivity (E-configuration preference) and chemoselectivity (chloration or F-C alkylation) are mainly controlled by the steric effect rather than the electronic effect. The main findings of the present work provide a new way to analyze and rationalize various Ga-mediated reactions, which might also be extrapolated to organic transformations undergoing in the presence of aluminum and indium complexes.

17.
Math Biosci Eng ; 17(4): 3450-3477, 2020 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-32987538

RESUMEN

In the field of remote sensing image processing, the classification of hyperspectral image (HSI) is a hot topic. There are two main problems lead to the classification accuracy unsatisfactory. One problem is that the recent research on HSI classification is based on spectral features, the relationship between different pixels has been ignored; the other is that the HSI data does not contain or only contain a small amount of labeled data, so it is impossible to build a well classification model. To solve these problems, a dual-channel CNN model has been proposed to boost its discriminative capability for HSI classification. The proposed dual-channel CNN model has several distinct advantages. Firstly, the model consists of spectral feature extraction channel and spatial feature extraction channel; the 1-D CNN and 3-D CNN are used to extract the spectral and spatial features, respectively. Secondly, the dual-channel CNN have been used for fusing the spatial-spectral features, the fusion feature is input into the classifier, which effectively improves the classification accuracy. Finally, due to considering the spatial and spectral features, the model can effectively solve the problem of lack of training samples. The experiments on benchmark data sets have demonstrated that the proposed dual-channel CNN model considerably outperforms other state-of-the-art method.

18.
ACS Appl Mater Interfaces ; 10(4): 3602-3608, 2018 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-29313326

RESUMEN

The synthesis and growth of CH3NH3PbI3 films with controlled nucleation is a key issue for the high efficiency and stability of solar cells. Here, 4-tert-butylpyridine (tBP) was introduced into a CH3NH3PbI3 antisolvent to obtain high quality perovskite layers. In situ optical microscopy and X-ray diffraction patterns were used to prove that tBP significantly suppressed perovskite nucleation by forming an intermediate phase. In addition, a gradient perovskite structure was obtained by this method, which greatly improved the efficiency and stability of perovskites. An effective power conversion efficiency (PCE) of 17.41% was achieved via the tBP treatment, and the high-efficiency device could maintain over 89% of the initial PCE after 30 days at room temperature.

19.
Reprod Sci ; 25(4): 566-578, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28691579

RESUMEN

OBJECTIVE: Epithelial-mesenchymal transition (EMT) is essential for embryogenesis, fibrosis, and tumor metastasis. Aberrant EMT phenomenon has been reported in endometriotic tissues of patients with endometriosis (EM). In this study, we further investigated the molecular mechanism of which lipoxin A4 (LXA4) suppresses estrogen (E2)-induced EMT in EM. STUDY DESIGN: The EMT markers were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot in eutopic endometrial epithelial cells (EECs) or investigated by immunohistochemistry and qRT-PCR in endometriotic lesion of EM mice. The invasion and migration under different treatments were assessed by transwell assays with or without Matrigel. The messenger RNA (mRNA) and activities of matrix metalloproteinase 2 (MMP-2) and MMP-9 were determined by qRT-PCR and gelatin zymography, respectively. Luciferase reporter assay was used to measure the activity of zinc finger E-box binding homeobox 1(ZEB1) promoter. The level of E2 in endometriotic tissues was assessed by enzyme-linked immunosorbent assay. RESULTS: In eutopic EECs, stimulatory effects of E2 on EMT progress, migration, and invasion were all diminished by LXA4. Lipoxin A4 reduced E2-induced ZEB1 promoter activity. Lipoxin A4 also attenuated the phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase induced by E2. Co-incubation with Boc-2 rather than DMF antagonized the influence of LXA4. Animal experiments showed that LXA4 inhibited the EMT progress, MMP expression, and proteinase activities of endometriotic lesion in an LXA4 receptor (ALXR) manner, which suppressed the progression of EM. ZEB1 mRNA expression was upregulated and well correlated with E2 level in human endometrium. CONCLUSION: Lipoxin A4 suppresses E2-induced EMT via ALXR-dependent manner in eutopic EECs, which reveals a novel biological effect of LXA4 in EM.


Asunto(s)
Endometriosis/metabolismo , Endometrio/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Estradiol/metabolismo , Lipoxinas/farmacología , Enfermedades del Ovario/metabolismo , Adulto , Animales , Movimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Endometrio/metabolismo , Estradiol/farmacología , Femenino , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Persona de Mediana Edad , Fosforilación/efectos de los fármacos , Adulto Joven
20.
ACS Appl Mater Interfaces ; 10(3): 2603-2611, 2018 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-29285921

RESUMEN

To achieve high-quality perovskite solar cells (PSCs), the morphology and carrier transportation of perovskite films need to be optimized. Herein, C60 is employed as nucleation sites in PbI2 precursor solution to optimize the morphology of perovskite films via vapor-assisted deposition process. Accompanying the homogeneous nucleation of PbI2, the incorporation of C60 as heterogeneous nucleation sites can lower the nucleation free energy of PbI2, which facilitates the diffusion and reaction between PbI2 and organic source. Meanwhile, C60 could enhance carrier transportation and reduce charge recombination in the perovskite layer due to its high electron mobility and conductivity. In addition, the grain sizes of perovskite get larger with C60 optimizing, which can reduce the grain boundaries and voids in perovskite and prevent the corrosion because of moisture. As a result, we obtain PSCs with a power conversion efficiency (PCE) of 18.33% and excellent stability. The PCEs of unsealed devices drop less than 10% in a dehumidification cabinet after 100 days and remain at 75% of the initial PCE during exposure to ambient air (humidity > 60% RH, temperature > 30 °C) for 30 days.

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