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1.
Nat Commun ; 15(1): 3687, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38693124

ABSTRACT

The performance of superconducting quantum circuits for quantum computing has advanced tremendously in recent decades; however, a comprehensive understanding of relaxation mechanisms does not yet exist. In this work, we utilize a multimode approach to characterizing energy losses in superconducting quantum circuits, with the goals of predicting device performance and improving coherence through materials, process, and circuit design optimization. Using this approach, we measure significant reductions in surface and bulk dielectric losses by employing a tantalum-based materials platform and annealed sapphire substrates. With this knowledge we predict the relaxation times of aluminum- and tantalum-based transmon qubits, and find that they are consistent with experimental results. We additionally optimize device geometry to maximize coherence within a coaxial tunnel architecture, and realize on-chip quantum memories with single-photon Ramsey times of 2.0 - 2.7 ms, limited by their energy relaxation times of 1.0 - 1.4 ms. These results demonstrate an advancement towards a more modular and compact coaxial circuit architecture for bosonic qubits with reproducibly high coherence.

2.
Adv Mater ; 36(18): e2310280, 2024 May.
Article in English | MEDLINE | ID: mdl-38197525

ABSTRACT

Scaling up superconducting quantum circuits based on transmon qubits necessitates substantial enhancements in qubit coherence time. Over recent years, tantalum (Ta) has emerged as a promising candidate for transmon qubits, surpassing conventional counterparts in terms of coherence time. However, amorphous surface Ta oxide layer may introduce dielectric loss, ultimately placing a limit on the coherence time. In this study, a novel approach for suppressing the formation of tantalum oxide using an ultrathin magnesium (Mg) capping layer is presented. Synchrotron-based X-ray photoelectron spectroscopy studies demonstrate that oxide is confined to an extremely thin region directly beneath the Mg/Ta interface. Additionally, it is demonstrated that the superconducting properties of thin Ta films are improved following the Mg capping, exhibiting sharper and higher-temperature transitions to superconductive and magnetically ordered states. Moreover, an atomic-scale mechanistic understanding of the role of the capping layer in protecting Ta from oxidation is established based on computational modeling. This work provides valuable insights into the formation mechanism and functionality of surface tantalum oxide, as well as a new materials design principle with the potential to reduce dielectric loss in superconducting quantum materials. Ultimately, the findings pave the way for the realization of large-scale, high-performance quantum computing systems.

3.
Nat Commun ; 14(1): 7555, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-37985764

ABSTRACT

Macrophages sense changes in the extracellular matrix environment through the integrins and play a central role in regulation of the reparative response after myocardial infarction. Here we show that macrophage integrin α5 protects the infarcted heart from adverse remodeling and that the protective actions are associated with acquisition of an angiogenic macrophage phenotype. We demonstrate that myeloid cell- and macrophage-specific integrin α5 knockout mice have accentuated adverse post-infarction remodeling, accompanied by reduced angiogenesis in the infarct and border zone. Single cell RNA-sequencing identifies an angiogenic infarct macrophage population with high Itga5 expression. The angiogenic effects of integrin α5 in macrophages involve upregulation of Vascular Endothelial Growth Factor A. RNA-sequencing of the macrophage transcriptome in vivo and in vitro followed by bioinformatic analysis identifies several intracellular kinases as potential downstream targets of integrin α5. Neutralization assays demonstrate that the angiogenic actions of integrin α5-stimulated macrophages involve activation of Focal Adhesion Kinase and Phosphoinositide 3 Kinase cascades.


Subject(s)
Integrin alpha5 , Myocardial Infarction , Mice , Animals , Integrin alpha5/metabolism , Vascular Endothelial Growth Factor A/metabolism , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Myocardial Infarction/genetics , Myocardial Infarction/metabolism , Macrophages/metabolism , Mice, Knockout , RNA/metabolism
4.
Front Endocrinol (Lausanne) ; 14: 1294909, 2023.
Article in English | MEDLINE | ID: mdl-38027163

ABSTRACT

Background: The triglyceride glucose-body mass index (TyG-BMI) is a surrogate indicator of insulin resistance. However, the association of TyG-BMI with heart failure (HF) in individuals with diabetes mellitus or prediabetes mellitus is unknown. Methods: This study included 7,472 participants aged 20-80 years old with prediabetes or diabetes from the National Health and Nutrition Examination Survey (2007-2018). The TyG-BMI was calculated as Ln [triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI, and individuals were categorized into tertiles based on TyG-BMI levels. The relationship of TyG-BMI with HF was analyzed using multiple logistic regression models. Subgroup analyses were stratified by gender, age, hypertension, and diabetes mellitus status. Results: This cross-sectional study had 7,472 participants (weighted n = 111,808,357), including 329 HF participants. Participants with a high TyG-BMI were prone to HF. The highest tertile group with a fully adjusted model was more likely to have HF compared to the lowest tertile group (odds ratio [OR], 2.645; 95% CI, 1.529-4.576). Restricted cubic spline analysis showed a significant dose-response relationship between TyG-BMI and HF (P < 0.001). In subgroup analyses, similar results were seen in terms of age (≥50 years old), gender, hypertension, and diabetes mellitus status. Conclusion: A high TyG-BMI is significantly associated with HF risk in participants with diabetes mellitus or prediabetes mellitus.


Subject(s)
Diabetes Mellitus, Type 2 , Heart Failure , Hypertension , Prediabetic State , Humans , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Prediabetic State/complications , Prediabetic State/epidemiology , Prediabetic State/diagnosis , Glucose , Body Mass Index , Cross-Sectional Studies , Triglycerides , Nutrition Surveys , Risk Factors , Blood Glucose/analysis , Heart Failure/epidemiology , Heart Failure/etiology
5.
BMC Public Health ; 23(1): 1862, 2023 09 26.
Article in English | MEDLINE | ID: mdl-37752456

ABSTRACT

BACKGROUND: In previous studies, sun-protective behaviors increased cardiovascular incidence. Our present article is to further analyze the potential relationship between sun-protective behaviors (staying in the shade, wearing long-sleeved clothing, and applying sunscreen) and hypertension. METHOD: The present cross-sectional study evaluated 8,613 participants (aged 20-60 years) from the National Health and Nutrition Examination Survey (NHANES) obtained between 2009 and 2014. We performed multiple logistic regression analysis to examine the relationship between sun-protective behaviors and hypertension. Subgroup analysis was then performed. Multiple linear regression analysis was utilized to examine the relationship of sun-protective behaviors and each sun-protective behavior with systolic and diastolic blood pressure, stratified by sex and race. RESULTS: A total of 8,613 participants (weighted n = 127,909,475) were applied in our study, including 1,694 hypertensive subjects. Our study demonstrated that sun-protective behaviors of the 2-3 category were associated with increased risk of hypertension, but not with higher systolic and diastolic blood pressure. In subgroup analysis, men, Mexican American, and 25 < BMI ≤ 30 who reported sun-protective behaviors (2-3) were prone to hypertension. Multiple linear regression models showed that non-Hispanic white men with sun-protective behaviors (2-3) were positively associated with systolic and diastolic blood pressure. The association between other-Hispanic men with frequent wearing long-sleeved clothing and diastolic blood pressure was positively correlated. CONCLUSION: Sun-protective behaviors of the 2-3 category could increase the incidence of hypertension, but not increase systolic and diastolic blood pressure. We only found that non-Hispanic white men who reported sun-protective behaviors (2-3) were positively associated with systolic and diastolic blood pressure. These findings suggested that excessive sun-protective behaviors should be avoided.


Subject(s)
Hypertension , Skin Neoplasms , Male , Humans , Nutrition Surveys , Cross-Sectional Studies , Health Behavior , Hypertension/epidemiology , Hypertension/prevention & control , Hypertension/drug therapy , Sunscreening Agents/therapeutic use
6.
Adv Sci (Weinh) ; 10(21): e2300921, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37166044

ABSTRACT

Over the past decades, superconducting qubits have emerged as one of the leading hardware platforms for realizing a quantum processor. Consequently, researchers have made significant effort to understand the loss channels that limit the coherence times of superconducting qubits. A major source of loss has been attributed to two level systems that are present at the material interfaces. It is recently shown that replacing the metal in the capacitor of a transmon with tantalum yields record relaxation and coherence times for superconducting qubits, motivating a detailed study of the tantalum surface. In this work, the chemical profile of the surface of tantalum films grown on c-plane sapphire using variable energy X-ray photoelectron spectroscopy (VEXPS) is studied. The different oxidation states of tantalum that are present in the native oxide resulting from exposure to air are identified, and their distribution through the depth of the film is measured. Furthermore, it is shown how the volume and depth distribution of these tantalum oxidation states can be altered by various chemical treatments. Correlating these measurements with detailed measurements of quantum devices may elucidate the underlying microscopic sources of loss.

7.
Small ; 19(12): e2206245, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36587963

ABSTRACT

In recent years, carbon-based CsPbI2 Br perovskite solar cells (PSCs) have attracted more attention due to their low cost and good stability. However, the power conversion efficiency (PCE) of carbon-based CsPbI2 Br PSCs is still no more than 16%, because of the defects in CsPbI2 Br or at the interface with the electron transport layer (ETL), as well as the energy level mismatch, which lead to the loss of energy, thus limiting PCE values. Herein, a series of cadmium halides are introduced, including CdCl2 , CdBr2 and CdI2 for dual direction thermal diffusion treatment. Some Cd2+ ions thermally diffuse downward to passivate the defects inside or on the surface of SnO2 ETL. Meanwhile, the energy level structure of SnO2 ETL is adjusted, which is in favor of the transfer of electron carriers and blocking holes. On the other hand, part of Cd2+ and Cl- ions thermally diffuse upward into the CsPbI2 Br lattice to passivate crystal defects. Through dual direction thermal diffusion treatment by CdCl2 , CdI2 and CdBr2 , the performance of devices has been significantly improved, and their PCE has been increased from 13.01% of the original device to 14.47%, 14.31%, and 13.46%, respectively. According to existing reports, 14.47% is one of the highest PCE of carbon-based CsPbI2 Br PSCs with SnO2 ETLs.

8.
Nanotechnology ; 34(12)2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36538812

ABSTRACT

Discovery of structure-property relationships in thin film alloys of complex metal oxides enabled by high-throughput materials synthesis and characterization facilities is demonstrated here with a case-study. Thin films of binary transition metal oxides (Ti-Zn) are prepared by pulsed laser deposition with continuously varying Ti:Zn ratio, creating combinatorial samples for exploration of the properties of this material family. The atomic structure and electronic properties are probed by spatially resolved techniques including x-ray absorption near edge structures (XANES) and x-ray fluorescence (XRF) at the Ti and Zn K-edge, x-ray diffraction, and spectroscopic ellipsometry. The observed properties as a function of Ti:Zn ratio are resolved into mixtures of five distinguishable phases by deploying multivariate curve resolution analysis on the XANES spectral series, under constraints set by results from the other characterization techniques. First-principles computations based on density function theory connect the observed properties of each distinct phase with structural and spectral characteristics of crystalline polymorphs of Ti-Zn oxide. Continuous tuning of the optical absorption edge as a function of Ti:Zn ratio, including the unusual observation of negative optical bowing, exemplifies a functional property of the film correlated to the phase evolution.

9.
J Mol Cell Cardiol ; 172: 1-13, 2022 11.
Article in English | MEDLINE | ID: mdl-35872324

ABSTRACT

Cells sense mechanical stress and changes in their matrix environment through the integrins, a family of heterodimeric surface receptors that bind to extracellular matrix ligands and trigger cytoskeletal remodeling, while transducing a wide range of intracellular signals. Integrins have been extensively implicated in regulation of inflammation, repair and fibrosis in many different tissues. This review manuscript discusses the role of integrin-mediated cascades in myocardial fibrosis. In vitro studies have demonstrated that ß1 and αv integrins play an important role in fibrogenic conversion of cardiac fibroblast, acting through direct stimulation of FAK/Src cascades, or via accentuation of growth factor signaling. Fibrogenic actions of αv integrins may be mediated, at least in part, through pericellular activation of latent TGF-ß stores. In vivo evidence supporting the role of integrin heterodimers in fibrotic cardiac remodeling is limited to associative evidence, and to experiments using pharmacologic inhibitors, or global loss-of-function approaches. Studies documenting in vivo actions of integrins on fibroblasts using cell-specific strategies are lacking. Integrin effects on leukocytes may also contribute to the pathogenesis of fibrotic myocardial responses by mediating recruitment and activation of fibrogenic macrophages. The profile and role of integrins in cardiac fibrosis may be dependent on the underlying pathologic condition. Considering their cell surface localization and the availability of small molecule inhibitors, integrins may be attractive therapeutic targets for patients with heart failure associated with prominent fibrotic remodeling.


Subject(s)
Fibroblasts , Integrins , Humans , Integrins/metabolism , Fibrosis , Fibroblasts/metabolism , Extracellular Matrix/metabolism , Transforming Growth Factor beta/metabolism
10.
J Mol Cell Cardiol ; 171: 1-15, 2022 10.
Article in English | MEDLINE | ID: mdl-35780861

ABSTRACT

TGF-ßs regulate macrophage responses, by activating Smad2/3. We have previously demonstrated that macrophage-specific Smad3 stimulates phagocytosis and mediates anti-inflammatory macrophage transition in the infarcted heart. However, the role of macrophage Smad2 signaling in myocardial infarction remains unknown. We studied the role of macrophage-specific Smad2 signaling in healing mouse infarcts, and we explored the basis for the distinct effects of Smad2 and Smad3. In infarct macrophages, Smad3 activation preceded Smad2 activation. In contrast to the effects of Smad3 loss, myeloid cell-specific Smad2 disruption had no effects on mortality, ventricular dysfunction and adverse remodeling, after myocardial infarction. Macrophage Smad2 loss modestly, but transiently increased myofibroblast density in the infarct, but did not affect phagocytic removal of dead cells, macrophage infiltration, collagen deposition, and scar remodeling. In isolated macrophages, TGF-ß1, -ß2 and -ß3, activated both Smad2 and Smad3, whereas BMP6 triggered only Smad3 activation. Smad2 and Smad3 had similar patterns of nuclear translocation in response to TGF-ß1. RNA-sequencing showed that Smad3, and not Smad2, was the main mediator of transcriptional effects of TGF-ß on macrophages. Smad3 loss resulted in differential expression of genes associated with RAR/RXR signaling, cholesterol biosynthesis and lipid metabolism. In both isolated bone marrow-derived macrophages and in infarct macrophages, Smad3 mediated synthesis of Nr1d2 and Rara, two genes encoding nuclear receptors, that may be involved in regulation of their phagocytic and anti-inflammatory properties. In conclusion, the in vivo and in vitro effects of TGF-ß on macrophage function involve Smad3, and not Smad2.


Subject(s)
Myocardial Infarction , Smad2 Protein , Smad3 Protein , Animals , Cholesterol , Collagen/metabolism , Macrophages/metabolism , Mice , Mice, Knockout , Myocardial Infarction/metabolism , Myocardium/metabolism , Phenotype , RNA , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Transforming Growth Factor beta/metabolism
11.
FASEB J ; 36(7): e22400, 2022 07.
Article in English | MEDLINE | ID: mdl-35695814

ABSTRACT

Smad7 restrains TGF-ß responses, and has been suggested to exert both pro- and anti-inflammatory actions that may involve effects on macrophages. Myocardial infarction triggers a macrophage-driven inflammatory response that not only plays a central role in cardiac repair, but also contributes to adverse remodeling and fibrosis. We hypothesized that macrophage Smad7 expression may regulate inflammation and fibrosis in the infarcted heart through suppression of TGF-ß responses, or via TGF-independent actions. In a mouse model of myocardial infarction, infiltration with Smad7+ macrophages peaked 7 days after coronary occlusion. Myeloid cell-specific Smad7 loss in mice had no effects on homeostatic functions and did not affect baseline macrophage gene expression. RNA-seq predicted that Smad7 may promote TREM1-mediated inflammation in infarct macrophages. However, these alterations in the transcriptional profile of macrophages were associated with a modest and transient reduction in infarct myofibroblast infiltration, and did not affect dysfunction, chamber dilation, scar remodeling, collagen deposition, and macrophage recruitment. In vitro, RNA-seq and PCR arrays showed that TGF-ß has profound effects on macrophage profile, attenuating pro-inflammatory cytokine/chemokine expression, modulating synthesis of matrix remodeling genes, inducing genes associated with sphingosine-1 phosphate activation and integrin signaling, and inhibiting cholesterol biosynthesis genes. However, Smad7 loss did not significantly affect TGF-ß-mediated macrophage responses, modulating synthesis of only a small fraction of TGF-ß-induced genes, including Itga5, Olfml3, and Fabp7. Our findings suggest a limited role for macrophage Smad7 in regulation of post-infarction inflammation and repair, and demonstrate that the anti-inflammatory effects of TGF-ß in macrophages are not restrained by endogenous Smad7 induction.


Subject(s)
Myocardial Infarction , Smad7 Protein/metabolism , Animals , Fibrosis , Inflammation , Macrophages/metabolism , Mice , Myocardial Infarction/genetics , Myocardial Infarction/metabolism , Phenotype , Smad7 Protein/genetics , Transforming Growth Factor beta/metabolism
12.
Sci Rep ; 12(1): 4542, 2022 03 16.
Article in English | MEDLINE | ID: mdl-35296717

ABSTRACT

Reliable tools for macrophage identification in mouse tissues are critical for studies investigating inflammatory and reparative responses. Transgenic reporter mice and anti-macrophage antibodies have been used as "specific pan-macrophage" markers in many studies; however, organ-specific patterns of expression and non-specific labeling of other cell types, such as fibroblasts, may limit their usefulness. Our study provides a systematic comparison of macrophage labeling patterns in normal and injured mouse tissues, using the CX3CR1 and CSF1R macrophage reporter lines and anti-macrophage antibodies. Moreover, we tested the specificity of macrophage antibodies using the fibroblast-specific PDGFR[Formula: see text] reporter line. Mouse macrophages exhibit organ-specific differences in expression of macrophage markers. Hepatic macrophages are labeled for CSF1R, Mac2 and F4/80, but lack CX3CR1 expression, whereas in the lung, the CSF1R+/Mac2+/Mac3+ macrophage population is not labeled with F4/80. In the splenic red pulp, subpopulations of CSF1R+/F4/80+/Mac3+cells were labeled with Mac2, CX3CR1 and lysozyme M. In the kidney, Mac2, Mac3 and lysozyme M labeled a fraction of the CSF1R+ and CX3CR1+ macrophages, but also stained tubular epithelial cells. In normal hearts, the majority of CSF1R+ and CX3CR1+ cells were not detected with anti-macrophage antibodies. Myocardial infarction was associated with marked expansion of the CSF1R+ and CX3CR1+ populations that peaked during the proliferative phase of cardiac repair, and also expressed Mac2, Mac3 and lysozyme M. In normal mouse tissues, a small fraction of cells labeled with anti-macrophage antibodies were identified as PDGFR[Formula: see text]+ fibroblasts, using a reporter system. The population of PDGFR[Formula: see text]+ cells expressing macrophage markers expanded following injury, likely reflecting emergence of cellular phenotypes with both fibroblast and macrophage characteristics. In conclusion, mouse macrophages exhibit remarkable heterogeneity. Selection of the most appropriate markers for identification of macrophages in mouse tissues is dependent on the organ and the pathologic condition studied.


Subject(s)
Macrophages , Muramidase , Animals , Biomarkers/metabolism , Kupffer Cells/metabolism , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Muramidase/metabolism , Receptor Protein-Tyrosine Kinases/metabolism
13.
J Colloid Interface Sci ; 616: 201-209, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35203033

ABSTRACT

TiO2 is commonly used to prepare electron transport layers (ETLs) in perovskite solar cells (PSCs). However, conventional TiO2 ETLs suffer from low electron mobility and charge recombination. Here, we report the direct growth of TiO2 ETLs on fluorine doped conductive (FTO) glasses with titanium tetrafluoride (TiF4) as the reactant by hydrothermal method. The TiO2 ETLs have pure anatase phase, single crystal structure and three-dimensional (3D) nanoarrays morphology. This 3D-TiO2 ETLs mainly consist of thermodynamically stable surfaces {101} and more reactive surfaces {001}. Compared with the conventional TiO2 ETLs, the 3D-TiO2 ETLs can effectively optimize energy level matching and charge transfer dynamics. The special morphology of 3D-TiO2 ETLs can well assist to form high quality CsPbIBr2 with larger crystal grains. The champion CsPbIBr2 PSC with 3D-TiO2 ETL achieves an efficiency as high as 10.65%, which is equal to the one with hole-transport and Au electrode structure (10.79%) and much higher than the pristine one (7.16%) with the conventional TiO2 ETL. Furthermore, the 3D-TiO2 ETLs show ultraviolet (UV) shielding function, which can effectively overcome the UV instability defect of conventional TiO2 ETLs and obviously enhance UV stability of CsPbIBr2 and the corresponding PSCs. Therefore, the 3D-TiO2 ETLs can be good candidates for preparing high-efficiency and UV stable carbon-based CsPbIBr2 PSCs.

14.
J Clin Invest ; 132(3)2022 02 01.
Article in English | MEDLINE | ID: mdl-34905511

ABSTRACT

Repair of the infarcted heart requires TGF-ß/Smad3 signaling in cardiac myofibroblasts. However, TGF-ß-driven myofibroblast activation needs to be tightly regulated in order to prevent excessive fibrosis and adverse remodeling that may precipitate heart failure. We hypothesized that induction of the inhibitory Smad, Smad7, may restrain infarct myofibroblast activation, and we examined the molecular mechanisms of Smad7 actions. In a mouse model of nonreperfused infarction, Smad3 activation triggered Smad7 synthesis in α-SMA+ infarct myofibroblasts, but not in α-SMA-PDGFRα+ fibroblasts. Myofibroblast-specific Smad7 loss increased heart failure-related mortality, worsened dysfunction, and accentuated fibrosis in the infarct border zone and in the papillary muscles. Smad7 attenuated myofibroblast activation and reduced synthesis of structural and matricellular extracellular matrix proteins. Smad7 effects on TGF-ß cascades involved deactivation of Smad2/3 and non-Smad pathways, without any effects on TGF-ß receptor activity. Unbiased transcriptomic and proteomic analysis identified receptor tyrosine kinase signaling as a major target of Smad7. Smad7 interacted with ErbB2 in a TGF-ß-independent manner and restrained ErbB1/ErbB2 activation, suppressing fibroblast expression of fibrogenic proteases, integrins, and CD44. Smad7 induction in myofibroblasts serves as an endogenous TGF-ß-induced negative feedback mechanism that inhibits postinfarction fibrosis by restraining Smad-dependent and Smad-independent TGF-ß responses, and by suppressing TGF-ß-independent fibrogenic actions of ErbB2.


Subject(s)
Heart Failure/metabolism , Myocardial Infarction/metabolism , Myofibroblasts/metabolism , Receptor, ErbB-2/metabolism , Smad7 Protein/metabolism , Transforming Growth Factor beta/metabolism , Animals , Heart Failure/etiology , Heart Failure/genetics , Mice , Mice, Knockout , Myocardial Infarction/complications , Myocardial Infarction/genetics , Receptor, ErbB-2/genetics , Smad7 Protein/genetics , Transforming Growth Factor beta/genetics
15.
J Colloid Interface Sci ; 607(Pt 2): 1280-1286, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34583033

ABSTRACT

Before completely applying inorganic materials as hole transport materials (HTM) for perovskite solar cells (PSCs), modifying devices with inorganic oxides that have the potential as inorganic hole transporters is an effective way to improve device performance and stability. Co2+ doped CuGaO2 nanocrystals (Co-CuGaO2 NCs) with sizes about 20 nm are synthesized by hydrothermal method and used for surface passivation at the interface of perovskite (PVK)/2,2',7,7'-Tetrakis[N,N-di (4-methoxyphenyl) amino]-9,9'-spirobifluorene (spiroOMeTAD). Co-CuGaO2 NCs have a larger bandgap with lower valance band compared with spiroOMeTAD, which is more beneficial to the conduction of holes and the blocking of electrons. Furthermore, the Co-CuGaO2 has a lower valance band energy compared with the original CuGaO2, which reduces the energy gap between Co-CuGaO2 and PVK. Co-CuGaO2 NCs fully cover the upper surface of PVK, which helps prevent direct contact between PVK and oxygen and moisture. The Co-CuGaO2 NCs surface passivation also gives better hole transport as revealed by the ultraviolet photoelectron spectroscopy (UPS), steady-state photoluminescence (PL), and time-resolved photoluminescence (TRPL) data. When the concentration of Co-CuGaO2 NCs solution is set to 7.5 mg mL-1, the device exhibits a best PCE of 20.39% and maintains 84.34% of the initial power conversion efficiency (PCE) after stored 30 days under air atmosphere with 15 ±â€¯5% humidity.

16.
Matrix Biol ; 99: 18-42, 2021 05.
Article in English | MEDLINE | ID: mdl-34048934

ABSTRACT

Tissue injury results in profound alterations in the collagen network, associated with unfolding of the collagen triple helix, proteolytic degradation and generation of fragments. In the infarcted myocardium, changes in the collagen network are critically involved in the pathogenesis of left ventricular rupture, adverse remodeling and chronic dysfunction. We hypothesized that myocardial infarction is associated with temporally and spatially restricted patterns of collagen denaturation that may reflect distinct molecular mechanisms of collagen unfolding. We used a mouse model of non-reperfused myocardial infarction, and in vitro assays in fibroblast-populated collagen lattices. In healing infarcts, labeling with collagen hybridizing peptide (CHP) revealed two distinct patterns of collagen denaturation. During the inflammatory and proliferative phases of infarct healing, collagen denaturation was pericellular, localized in close proximity to macrophages and myofibroblasts. qPCR array analysis of genes associated with matrix remodeling showed that Membrane Type 1-Matrix Metalloproteinase (MT1-MMP) is markedly upregulated in infarct macrophages and fibroblasts, suggesting its involvement in pericellular collagen denaturation. In vitro, MT1-MMP-mediated pericellular collagen denaturation is involved in cardiac fibroblast migration. The effects of MT1-MMP on collagen denaturation and fibroblast migration involve the catalytic site, and require hemopexin domain-mediated actions. In contrast, during the maturation phase of infarct healing, extensive collagen denaturation was noted in the hypocellular infarct, in the infarct border zone and in the mitral valve annulus, in the absence of MT1-MMP. In vitro, mechanical tension in attached collagen lattices was sufficient to induce peripheral collagen denaturation. Our study suggests that in healing infarcts, early pericellular collagen denaturation may be important for migration of macrophages and reparative myofibroblasts in the infarct. Extensive denaturation of collagen fibers is noted in mature scars, likely reflecting mechanical tension. Chronic collagen denaturation may increase susceptibility of the matrix to proteolysis, thus contributing to progressive cardiac dilation and post-infarction heart failure.


Subject(s)
Matrix Metalloproteinase 14 , Myocardial Infarction , Animals , Collagen/metabolism , Matrix Metalloproteinase 14/genetics , Mice , Myocardial Infarction/genetics , Myocardium/metabolism , Proteolysis
17.
ACS Appl Mater Interfaces ; 13(17): 20251-20259, 2021 May 05.
Article in English | MEDLINE | ID: mdl-33902287

ABSTRACT

With great research potential, the perovskite solar cells (PSCs) have been well developed in recent years, but there are still some urgent issues like efficiency and hysteresis defects that severely limit their commercialization. Interface modification is a significant measure to reduce defects and promote performance. In the article, an easy and effective strategy of modifying the electron transport layer (ETL) with NaBr is proposed to improve efficiency and reduce hysteresis. The charge carrier dynamics can be greatly optimized by diffusing NaBr on the ETL. The efficiency of the NaBr coated device can achieve 21.16%, which is extremely higher than the control one and shows low hysteresis behavior with a hysteresis index reduced from 0.135 to 0.025. The results indicate that the NaBr modification provides a novel strategy for preparing PSCs with high efficiency and low hysteresis.

18.
Sci Rep ; 11(1): 2358, 2021 Jan 27.
Article in English | MEDLINE | ID: mdl-33504921

ABSTRACT

We present a new method for thin-film synthesis of the superconducting A15 phase of vanadium silicide with critical temperature higher than 13 K. Interdiffusion between a metallic vanadium film and the underlying silicon device layer in a silicon-on-insulator substrate, at temperatures between 650 and 750 °C, favors formation of the vanadium-rich A15 phase by limiting the supply of available silicon for the reaction. Energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction verify the stoichiometry and structure of the synthesized thin films. We measure superconducting critical currents of more than 106 amperes per square centimeter at low temperature in micron-scale bars fabricated from the material, and an upper critical magnetic field of 20 T, from which we deduce a superconducting coherence length of 4 nm, consistent with previously reported bulk values. The relatively high critical temperature of A15 vanadium silicide is an appealing property for use in silicon-compatible quantum devices and circuits.

19.
J Cardiovasc Transl Res ; 14(2): 355-364, 2021 04.
Article in English | MEDLINE | ID: mdl-32671648

ABSTRACT

Doxorubicin (DOX) is an effective chemotherapy. However, its usage has been associated with adverse effects. Salidroside (SAL) is an antioxidative drug, which confers protective effects against several diseases. Salidroside can attenuate cardiac dysfunction induced by DOX. Quaking (QKI) is identified as a protective factor that can inhibit cardiotoxicity medicated by DOX through the regulation of cardiac circular RNA expression. The present study investigated the role of QKI on the protective effect of SAL in the DOX-induced cardiotoxicity model. Results indicated that SAL attenuated DOX-induced adverse effects, including cardiac dysfunction, weight loss, and reactive oxygen species (ROS) production, and decreased the expression of BAX, caspase 3, and FoxO1. Also, it increased the Mn-SOD2 and QKI expression in vivo and in vitro. Furthermore, QKI knockdown suppressed anti-cardiotoxicity mediated by SAL. In conclusion, the results of the current study show that salidroside attenuates doxorubicin-induced cardiac dysfunction through activation of QKI/FoxO1 pathway.


Subject(s)
Forkhead Box Protein O1/metabolism , Glucosides/pharmacology , Heart Diseases/prevention & control , Myocytes, Cardiac/drug effects , Nerve Tissue Proteins/metabolism , Phenols/pharmacology , RNA-Binding Proteins/metabolism , Ventricular Function, Left/drug effects , Animals , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Cardiotoxicity , Cell Line , Disease Models, Animal , Doxorubicin , Forkhead Box Protein O1/genetics , Heart Diseases/chemically induced , Heart Diseases/metabolism , Heart Diseases/physiopathology , Male , Mice, Inbred C57BL , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Nerve Tissue Proteins/genetics , Oxidative Stress/drug effects , RNA-Binding Proteins/genetics , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Signal Transduction
20.
Curr Opin Physiol ; 19: 80-91, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33195890

ABSTRACT

Several members of the chemokine family are involved in regulation of fibrosis. This review manuscript discusses the role of the chemokines in the pathogenesis of myocardial fibrosis. The CC chemokine CCL2 exerts fibrogenic actions through recruitment and activation of monocytes and macrophages expressing its receptor, CCR2. Other CC chemokines may also contribute to fibrotic remodeling by recruiting subsets of fibrogenic macrophages. CXC chemokines containing the ELR motif may exert pro-fibrotic actions, through recruitment of activated neutrophils and subsequent formation of neutrophil extracellular traps (NETs), or via activation of fibrogenic monocytes. CXCL12 has also been suggested to exert fibrogenic actions through effects on fibroblasts and immune cells. In contrast, the CXCR3 ligand CXCL10 was found to reduce cardiac fibrosis, inhibiting fibroblast migration. Chemokines are critical links between inflammation and fibrosis in myocardial disease and may be promising therapeutic targets for patients with heart failure accompanied by prominent inflammation and fibrosis.

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