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1.
Phys Chem Chem Phys ; 25(43): 29633-29640, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37880996

RESUMO

We conducted first-principles calculations to investigate the dynamic braiding of local edge states and the spin topological transport mechanism in a strong topological MoS1.75Te0.25 matrix. The presence of type-II Van Hove singularity in the middle of the X-S path indicates a strong cohesive interaction and a paring condensation mechanism within the matrix. The surface state data of MoS1.75Te0.25 clearly demonstrate the characteristic features of strong regular loop braiding in spin transport. The spin Hall conductivity of the matrix was determined from the anisotropic characteristics of the spin Berry curvature. The phase transition of the spin Hall conductivity was evidenced by the positive sign of local spin polarization strength, primarily contributed by the dz2 orbital of Mo atoms, and the negative sign of spin polarization strength, mainly contributed by the p-px orbitals of S atoms. Moreover, the inclusion of Te selectively tuned the spin transport efficiency of the dz2 and px orbitals. Comprehensive braiding and readout of edge states can be achieved using an artificially designed MoS1.75Te0.25 spintronic device. This 2D fractional braiding holds significant potential for applications in topological quantum computation.

2.
Phys Chem Chem Phys ; 25(47): 32387-32392, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37997152

RESUMO

We theoretically demonstrate how the competition between band inversion and spin-orbit coupling (SOC) results in the nontrivial topology of band evolution, using two-dimensional (2D) Mn16B16 as a matrix. This study utilizes the ab initio method with the generalized gradient approximation (GGA+U scheme) and Wannier functions to investigate the topological and transport properties of the Ni-doped structure. The Ni atom induces dynamical antilocalization, which appears due to the phase accumulation between time-reversed fermion loops. A key observation is that when band inversion dominates over SOC, "twin" Weyl cones appear in the band structure, in which the Weyl cones caused by the large Berry curvature coupling with the net magnetization lead to the significantly enhanced anomalous Hall conductivity (AHC). Interestingly, the nested small polaron and energy band inversion coexist with SOC. An analysis of the projected energy band shows that the doped Ni atom induces a strong spin wave for both spin up and spin down.

3.
Phys Chem Chem Phys ; 24(31): 18983-18991, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35917181

RESUMO

We have successfully predicted the local topological bands in the frustrated kagome lattice SbV3S5. An important future research direction is to raise the kagome band with novel co-existing strong nonlinear dispersion and strong cohesion due to the anisotropic inner field of kagome SbV3S5 to the Fermi level. The Z2 topological index of T-invariant systems provides evidence for a σyz near the Fermi level that determines the quantum anomalous Hall state. This shows that the quantum anomalous Hall effect (QAHE) phase of the kagome lattice SbV3S5 has a weak topological stability that is sensitive to weak disorder and field interactions. Neighbouring van Hove singularities near the Fermi level induced a quantum anomalous Hall conductivity and charge density wave platform.

4.
Kidney Blood Press Res ; 47(6): 375-390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35114677

RESUMO

BACKGROUND: Renal anemia is an important complication of chronic kidney disease (CKD). In addition to insufficient secretion of erythropoietin (EPO) and erythropoiesis disorders, the impact of eryptosis on renal anemia demands attention. However, a systemic analysis concerning the pathophysiology of eryptosis has not been expounded. SUMMARY: The complicated conditions in CKD patients, including oxidative stress, osmotic stress, metabolic stress, accumulation of uremic toxins, and iron deficiency, affect the normal skeleton structure of red blood cells (RBCs) and disturbs ionic homeostasis, causing phosphatidylserine to translocate to the outer lobules of the RBC membrane that leads to early elimination and/or shortening of the RBC lifespan. Inadequate synthesis of RBCs cannot compensate for their accelerated destruction, thus exacerbating renal anemia. Meanwhile, EPO treatment alone will not reverse renal anemia. A variety of eryptosis inhibitors have so far been found, but evidence of their effectiveness in the treatment of CKD remains to be established. KEY MESSAGES: In this review, the pathophysiological processes and factors influencing eryptosis in CKD were elucidated. The aim of this review was to underline the importance of eryptosis in renal anemia and determine some promising research directions or possible therapeutic targets to correct anemia in CKD.


Assuntos
Anemia , Eriptose , Insuficiência Renal Crônica , Anemia/etiologia , Eritrócitos/metabolismo , Eritropoese , Humanos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo
5.
Opt Express ; 29(6): 8997-9011, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820338

RESUMO

A novel white-light copolymer matched with 365 nm chips is prepared by bonding the vinyl-functionalized complexes Eu(TTA)2(Phen)(MAA), Tb(p-BBA)3(UA) and Zn(BTZ)(UA) to polysiloxaneprepolymer(synthesized by polycondensation of vinyltrimethoxysilane and diphenylsilanediol) through a technical route of polymerization after coordination. Its structure was characterized by infrared and ultraviolet. Under the excitation of 365 nm, when the ratio of the tricolor complexes is controlled to be 0.5: 3: 1.5, white light copolymer with CIE color coordinates of (0.327, 0.321) was obtained and packaged to get white light LED devices. After aging, the CIE color coordinates of the device change from (0.325, 0.329) to (0.341, 0.348), the color rendering index changes from 91 to 88, and the correlated color temperature changes from 5967 K to 5612 K. The loss of brightness is only 10.4%, which shows good resistance to UV aging. Moreover, the initial decomposition temperature of the copolymer is 235°C. The above results show that the bonding-type anti-ultraviolet copolymer phosphor has potential application in near ultraviolet LEDs.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1677-81, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26601389

RESUMO

Titanium dioxide (TiO2) supported on spherical alumina substrate was prepared by using sol-gel method combined with dip-coating process. The surface morphology and structure of the synthesized samples were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) pattern. The results show that the morphology of the supported TiO2 composite material was obviously different from that of the original support. It reveals a layer formed by anatase TiO2 nanoparticles of 10-20 nm was deposited on the alumina substrate. Energy dispersive X-ray spectroscopy (EDX) analyses on the spherical alumina substrate and the resulting TiO2 composite catalyst were performed to determine the TiO2 loading content in the samples. It indicates that the TiO2 loading content on alumina substrate could be effectively increased by increasing the times of dip-coating alumina support in TiO2 sol. When dip-coating times increased to 5, the TiO2 loading content increased from 3.8 Wt. % to 15.7 Wt. %. In addition, the photocatalytic performances of the supported TiO2 materials prepared by different dip-coating times have been investigated by degrading methylene blue. It was found that the surface morphology of the supported TiO2 material was not only improved, but also the photocatalytic activity could be promoted significantly by increasing the dip-coating times. When the alumina substrate was dip-coated in TiO2 sol from 1 to 4 times, the degradation rate of methylene blue increased from 40% to 83.1%. However, after dip-coating the alumina support in TiO2 sol for 5 times, the degradation of methylene blue was only up to 85.6%. This indicates that the photocatalytic activity increased slowly when the TiO2 content in the supported catalyst was up to some extent. It is attributed to the continuous dip-coating resulted in less opportunities and weak intensity of illumination for the TiO2 nano-particles that under lower layer. The photocatalytic activity was relatively stable after repeated use of the supported TiO2 material for 5 times.

7.
J Burn Care Res ; 44(2): 477-480, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36548961

RESUMO

Purpura fulminans is a rare and rapidly progressive septic process characterized by the development of hemorrhagic and ecchymotic lesions and skin necrosis. In this work, we report a case of a 52-year-old woman admitted to the Department of Emergency due to progressive purpura. The physical examination demonstrated a decreased skin temperature, unpalpable dorsalis pedis arteries, and ecchymoses covering both lower extremities. Laboratory tests indicated disseminated intravascular coagulation with prolonged activated partial thromboplastin time (APTT), low prothrombin time (PT), elevated d-dimer levels, and a low platelet count. A diagnosis of purpura fulminans was made, and steroids, therapeutic plasma exchange and empiric therapy, including antibiotic and anticoagulation therapy, were initiated immediately. Our treatment resulted in a good and sustained clinical response, as evidenced by the receding of blood blisters and the normalization of the patient's coagulation factors, but bilateral below-knee amputation was inevitable. Finally, the patient recovered well and was discharged home without any complications other than amputation.


Assuntos
Queimaduras , Coagulação Intravascular Disseminada , Púrpura Fulminante , Feminino , Humanos , Pessoa de Meia-Idade , Púrpura Fulminante/terapia , Púrpura Fulminante/complicações , Queimaduras/complicações , Coagulação Intravascular Disseminada/terapia , Coagulação Intravascular Disseminada/complicações , Necrose , Extremidade Inferior
8.
Environ Sci Pollut Res Int ; 30(22): 62625-62640, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36947381

RESUMO

The behavior of short-term debt for long-term investment (SFLI) will probably worsen the business status of the enterprise and increase the financial risk of the enterprise. Will the credit term structure of heavily polluting enterprises improve or worsen as the environmental regulatory pressure increases? This study takes the implementation of China's new Environmental Protection Law (NEPL) as a quasi-natural experiment to evaluate the impact of environmental regulatory pressure on the short-term debt for long-term investment behavior of heavy-polluting enterprises by the approach of Difference-in-Differences (DID). The results reveals that the NEPL significantly helps heavy-polluting enterprises achieve a more sustainable development mode by alleviating their maturity mismatch problem between investment and financing of heavy-polluting enterprises, which is conducive to reducing business risks. The impact mechanisms test shows that environmental regulatory pressure is likely to inhibit their investment and financing behavior, and might generate a crowding-out effect of innovation. When considering the heterogeneity of enterprise, the impact of the NEPL is not significant in state-owned enterprises, key-monitoring enterprises, and large-scale enterprises. However, the non-consistent effect as well as the innovation crowding-out effect, need more collaborative governance countermeasures. This paper reveals the consequences of environmental regulation policies from the view of corporate's credit term structure and provides new evidence for supporting the Porter hypothesis through addressing the dilemma of SFLI in heavily polluting enterprises.


Assuntos
Comércio , Política Ambiental , China , Investimentos em Saúde , Pressão , Conservação dos Recursos Naturais
9.
Genes (Basel) ; 14(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37761889

RESUMO

Habenaria dentata has medicinal and ornamental value, but the number of wild populations is decreasing dramatically. Thus, conducting research on its genetic diversity and structure is necessary to provide a basis for its conservation. This study aimed to explore the genetic diversity of the wild plant H. dentata and protect and optimize its wild resources. The genetic diversity of 133 samples from six wild populations of H. dentata was analyzed using Inter Simple Sequence Repeat molecular markers to provide a scientific basis for the screening of improved germplasm resources. The results showed that the average number of alleles was 1.765, the average number of effective alleles was 1.424, the average Nei's gene diversity index was 0.252, the average Shannon diversity index was 0.381, and the average percentage of polymorphic loci was 76.499%. The variation within the populations was 77.34%, and the variation between the populations was 22.66%. The gene flow was 1.705, which was greater than 1. The results of the cluster analysis showed that the six populations were mainly divided into four clusters and were not classified according to their geographical location. There was no significant correlation between the geographical location and genetic distance between the populations (r = 0.557, p > 0.05). The genetic diversity of H. dentata is high. Among the six wild populations, the genetic diversity of the Mulun population was the highest and this population can be used as a key protection unit. The study on the genetic diversity of H. dentata can not only reveal the reasons for the decrease in the number of individuals in the population to a certain extent, and put forward the protection strategy, but also provide a scientific basis for the breeding of excellent seed resources.


Assuntos
Variação Genética , Orchidaceae , Humanos , Variação Genética/genética , Melhoramento Vegetal , Repetições de Microssatélites/genética , Orchidaceae/genética , Análise por Conglomerados
10.
Resour Policy ; 75: 102524, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34975189

RESUMO

Since the emergence of the Covid-19 pandemic, global economic performance has been severely affected, which also causes natural resource price instability. Recently, scholars and policy-makers put more attention towards the global economic performance and natural resource volatility nexus. This study investigates four South Asian economies (Afghanistan, Bangladesh, India, and Pakistan) from 1991 to 2021. Using the (Pesaran, 2007) CIPS unit root test, the study found first differenced stationary data cointegrated as confirmed by the (Westerlund, 2007) cointegration test. However, this study employed the CCEMG approach to identify the association of natural resource volatility and economic performance in the selected region. Empirical results revealed that total natural resource rents, forest rents, and oil prices negatively and significantly affect economic performance. While oil rents, coal rents, and natural gas rents have a significant contribution to the region's economic performance. Results further illustrate a bidirectional causal association between economic performance and other variables except for coal rents, which is unidirectional. Based on the empirical findings, the current study acclaims some practical implications that could potentially reduce the negative influence of natural resources volatility on economic performance.

11.
Shock ; 58(2): 111-118, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36166194

RESUMO

ABSTRACTBACKGROUND: The expression of programmed cell death 1 receptor (PD-1) and CD28 on CD8+ T cells is considered to be related to immune function and prognosis markers in patients with sepsis. However, the relationship between the ratio of PD-1/CD28 and nosocomial infection has not been elucidated. Methods: A prospective, observational cohort study was conducted in a general intensive care unit. Patients were enrolled according to the sepsis-3 criteria and peripheral blood samples were collected within 24 hours of enrollment. Programmed cell death 1 receptor and CD28 expression on CD8+ T cells was assayed on day 1. Patients were followed up until 28 days. Multivariate regression analysis was used to assess independent risk factors for nosocomial infection. The accuracy of biomarkers for nosocomial infection and mortality was determined by the area under the receiver operating characteristic curve analysis. The association between biomarkers and 28-day mortality was assessed by Cox regression survival analysis. Results: A total of 181 patients were recruited, and 68 patients were finally included for analysis. Of these, 19 patients (27.9%) died during 28 days and 22 patients (32.4%) acquired nosocomial infection. The PD-1/CD28 ratio of patients with nosocomial infection was significantly higher than those without (0.27 [0.10-0.55] vs. 0.15 [0.08-0.28], P = 0.025). The PD-1/CD28 ratio in CD8+ T cells (odds ratio, 53.33; 95% confidence interval, 2.39-1188.22, P = 0.012) and duration of mechanical ventilation (odds ratio, 1.14; 95% confidence interval, 1.06-1.24; P = 0.001) were independently associated with nosocomial infection. The area under the receiver operating characteristic curve of PD-1/CD28 ratio in CD8+ T cells was 0.67 (0.52-0.82). The PD-1/CD28 ratio in CD8+ T cells of the nonsurvivors was significantly higher than the survivors (0.23 [0.15-0.52] vs. 0.14 [0.07-0.32]); Cox regression analysis showed that the survival time of patients with PD-1/CD28 ratio in CD8+ T cells of 0.13 or greater was shorter compared with patients with lower levels (hazard ratio, 4.42 [1.29-15.20], χ2 = 6.675; P = 0.010). Conclusions: PD-1/CD28 ratio in CD8+ T cells at admission may serve as a novel prognostic biomarker for predicting nosocomial infection and mortality.


Assuntos
Infecção Hospitalar , Sepse , Biomarcadores , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Humanos , Prognóstico , Receptor de Morte Celular Programada 1/metabolismo , Estudos Prospectivos , Sepse/metabolismo
12.
Am J Transl Res ; 12(11): 7439-7448, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33312380

RESUMO

Macrophages participate in all stages of sepsis and affect immune homeostasis and inflammatory processes. Small ubiquitin-like modifier (SUMO) protease SENP1 plays an important role in cellular inflammation by regulating proteins in SUMOylation. However, the roles and related mechanisms of SENP1 in macrophage inflammation during sepsis are largely unknown. In the present study, SENP1 expression was significantly promoted in lipopolysaccharide (LPS)-induced RAW 264.7 cells; furthermore, the knock down of SENP1 reduced the expression of inflammatory cytokines interleukin-6 and tumor necrosis factor-α. Momordin Ic (MC), a new type of SENP1 inhibitor, reduces LPS-induced cellular inflammation by depressing SENP1 expression. Moreover, the effect of SENP1 on LPS-induced inflammatory response was dependent on SENP1-Sp3 interaction and the promotion of Sp3 expression via Sp3 deSUMOylation. Furthermore, MC-depressed Sp3 expression disturbed Sp3-nuclear factor (NF)-κB interaction and then alleviated LPS-induced cellular inflammation. These results suggest that SENP1 promotes LPS-induced macrophage inflammation by promoting Sp3 expression via deSUMOylation and Sp3-NF-κB interaction in sepsis.

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