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1.
Cereb Cortex ; 34(10)2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39367727

RESUMO

Behavioral despair is one of the clinical manifestations of major depressive disorder and an important cause of disability and death. However, the neural circuit mechanisms underlying behavioral despair are poorly understood. In a well-established chronic behavioral despair (CBD) mouse model, using a combination of viral tracing, in vivo fiber photometry, chemogenetic and optogenetic manipulations, in vitro electrophysiology, pharmacological profiling techniques, and behavioral tests, we investigated the neural circuit mechanisms in regulating behavioral despair. Here, we found that CBD enhanced CaMKIIα neuronal excitability in the dorsal dentate gyrus (dDG) and dDGCaMKIIα neurons involved in regulating behavioral despair in CBD mice. Besides, dDGCaMKIIα neurons received 5-HT inputs from median raphe nucleus (MRN) and were mediated by 5-HT1A receptors, whereas MRN5-HT neurons received CaMKIIα inputs from lateral hypothalamic (LH) and were mediated by AMPA receptors to regulate behavioral despair. Furthermore, fluvoxamine exerted its role in resisting behavioral despair through the LH-MRN-dDG circuit. These findings suggest that a previously unidentified circuit of LHCaMKIIα-MRN5-HT-dDGCaMKIIα mediates behavioral despair induced by CBD. Furthermore, these support the important role of AMPA receptors in MRN and 5-HT1A receptors in dDG that might be the potential targets for treatment of behavioral despair, and explain the neural circuit mechanism of fluvoxamine-resistant behavioral despair.


Assuntos
Giro Denteado , Região Hipotalâmica Lateral , Animais , Giro Denteado/fisiologia , Giro Denteado/efeitos dos fármacos , Camundongos , Masculino , Região Hipotalâmica Lateral/fisiologia , Receptor 5-HT1A de Serotonina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Vias Neurais/fisiologia , Neurônios/fisiologia , Neurônios/metabolismo , Camundongos Endogâmicos C57BL , Fluvoxamina/farmacologia , Modelos Animais de Doenças , Depressão , Optogenética , Receptores de AMPA/metabolismo
2.
Chem Soc Rev ; 53(18): 9254-9305, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39143899

RESUMO

With the increasing demand for energy and the climate challenges caused by the consumption of traditional fuels, there is an urgent need to accelerate the adoption of green and sustainable energy conversion and storage technologies. The integration of flexible thermoelectrics with other various energy conversion technologies plays a crucial role, enabling the conversion of multiple forms of energy such as temperature differentials, solar energy, mechanical force, and humidity into electricity. The development of these technologies lays the foundation for sustainable power solutions and promotes research progress in energy conversion. Given the complexity and rapid development of this field, this review provides a detailed overview of the progress of multifunctional integrated energy conversion and storage technologies based on thermoelectric conversion. The focus is on improving material performance, optimizing the design of integrated device structures, and achieving device flexibility to expand their application scenarios, particularly the integration and multi-functionalization of wearable energy conversion technologies. Additionally, we discuss the current development bottlenecks and future directions to facilitate the continuous advancement of this field.

3.
J Am Chem Soc ; 146(2): 1681-1689, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38178655

RESUMO

The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.

4.
BMC Cancer ; 24(1): 1272, 2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39397012

RESUMO

Ovarian cancer is the fifth most prevalent cancer in women. Chemotherapy is a major treatment option for patients with advanced ovarian cancer (OC). Quinoline-2-thione and its derivatives are potential candidates for tumor therapy. In this study, we investigated the anticancer activity of the quinoline-2-thione derivative KA3D against ovarian cancer. The effect of KA3D on the viability of ovarian cancer cells was evaluated using MTT assay, and its effects on apoptosis and the cell cycle were detected using flow cytometry. Western blotting was performed to identify apoptosis-and cell cycle-related proteins altered by KA3D treatment. A xenograft model was used to verify the inhibitory effect of KA3D in vivo. H&E staining, biochemical indicator detection, and blood cell counts were used to observe the toxicity and side effects of KA3D. KA3D treatment impeded cell viability, induced apoptosis, and impeded the G2 phase of the cell cycle in ovarian cancer cells. Mechanistically, we found that KA3D enhanced the expression of proapoptotic molecules such as BAX and Caspase 3, while antiapoptotic proteins such as BCL2 were inhibited. The G0/G1 phase-related protein cyclin D1 was reduced and the G2 phase-related protein cyclin B1 was upregulated. In vivo, KA3D displayed potent anticancer activity, with no apparent toxicity in BABLC/c nude mice bearing SKOV3 cells. KA3D demonstrated remarkable chemotherapeutic drug efficacy in terms of significant cancer suppression in vitro and in vivo with low toxicity.


Assuntos
Antineoplásicos , Apoptose , Neoplasias Ovarianas , Quinolinas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Feminino , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Camundongos Nus , Tionas/farmacologia , Ciclo Celular/efeitos dos fármacos , Camundongos Endogâmicos BALB C
5.
Appl Opt ; 63(12): 3130-3137, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856457

RESUMO

Numerous applications at the photon-starved regime require a free-space coupling single-photon detector with a large active area, low dark count rate (DCR), and superior time resolutions. Here, we developed a superconducting microstrip single-photon detector (SMSPD), with a large active area of 260 µm in diameter, a DCR of ∼5k c p s, and a low time jitter of ∼171p s, operated at a near-infrared of 1550 nm and a temperature of ∼2.0K. As a demonstration, we applied the detector to a single-pixel galvanometer scanning system and successfully reconstructed the object information in depth and intensity using a time-correlated photon counting technology.

6.
Acc Chem Res ; 55(21): 3178-3190, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223096

RESUMO

ConspectusThe ever-growing energy crisis and the deteriorated environment caused by carbon energy consumption motivate the exploitation of alternative green and sustainable energy supplies. Because of the unique advantages of zero-emission, no moving parts, accurate temperature control, a long steady-state operation period, and the ability to operate in extreme situations, thermoelectrics, enabling the direct conversion between heat and electricity, is a promising and sustainable option for power generation and refrigeration. However, with increasing application potentials, thermoelectrics is now facing a major challenge: developing high-performance, Pb-free, and low-toxic thermoelectric materials and devices.As one group of promising candidates, GeTe derivatives have the potential to replace the widely used thermoelectric materials containing highly toxic elements. In this Account, we summarize our recent progress in developing high-performance GeTe-based thermoelectric materials via exploring innovative strategies to enhance electron transports and dampen phonon propagations. First, we fundamentally illustrate the underlying chemistry and physical reason for an intrinsically high carrier concentration in GeTe, which enormously restrains the thermoelectric performance of GeTe. From our theoretical calculations, the formation energy of Ge vacancy is the lowest among the defects in GeTe, energetically favoring Ge vacancies in the lattice and leading to intrinsically high carrier concentrations. Accordingly, aliovalent doping/alloying is proposed to increase the formation energy of Ge vacancies and decrease the carrier concentration to the optimal level. We then outline the newly developed method to refine the band structures of GeTe with tuned electronic transport. On the basis of the molecular orbital theory, the energy offset between two valence band edges at the L and Σ points in GeTe should be ascribed to the slightly different Ge_4s orbital characters at these two points, which guides the screening of dopants for band convergence. Besides, the Rashba spin splitting is explored to increase the band degeneracy of GeTe. Afterward, we analyze the dampened phonon propagation in GeTe to minimize its lattice thermal conductivity. Alloying with the heavy Sb atoms can shift the optical phonon modes toward low frequency and reinforce the interaction of optical and acoustic phonon modes so that the inherent phonon scattering is enhanced. In addition, planar vacancies and superlattice precipitates can significantly strengthen phonon scattering to result in ultralow lattice thermal conductivity. After that, we overview the finite elemental analysis simulations to optimize the device geometry for maximizing the device performance and introduce the as-developed prototype GeTe-based thermoelectric device. In the end, we point out future directions in the development of GeTe for device applications. The strategies summarized in this Account can serve as references for developing wide materials with enhanced thermoelectric performance.

7.
J Cardiovasc Pharmacol ; 81(1): 85-92, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36027482

RESUMO

ABSTRACT: Salidroside has anti-inflammatory and antiatherosclerotic effects, and mitochondrial homeostasis imbalance is closely related to cardiovascular disease. The aim of this study was to investigate the effect of salidroside on mitochondrial homeostasis after macrophage polarization and elucidate its possible mechanism against atherosclerosis. RAW264.7 cells were stimulated with 1 µg·mL -1 Lipopolysaccharide and 50 ng·mL -1 IFN-γ establish M1 polarization and were also pretreated with 400 µM salidroside. The relative expression of proinflammatory genes was detected by RT-PCR whereas that of mitochondrial homeostasis-related proteins and nuclear factor kappa-B (NF-κB) was detected by WB. Levels of intracellular reactive oxygen species (ROS), mitochondrial membrane potential, and mass were measured by chemifluorescence whereas that of NF-κB nuclear translocation was detected by immunofluorescence. Compared with the Mφ group, the M1 group demonstrated increased mRNA expression of interleukin-1ß , inductible nitric oxide synthase (iNOS), and tumor necrosis factor-α ; increased protein expression of iNOS, NOD-like receptor protein 3, putative kinase 1 , and NF-κB p65 but decreased protein expression of MFN2, Tom20, and PGC-1α; decreased mitochondrial membrane potential and mass; and increased ROS levels and NF-κB p65 nuclear translocation. Salidroside intervention decreased mRNA expression of interleukin-1ß and tumor necrosis factor-α compared with the M1 group but did not affect that of iNOS. Furthermore, salidroside intervention prevented the changes in protein expression, mitochondrial membrane potential and mass, ROS levels, and NF-κB p65 nuclear translocation observed in the M1 group. In summary, salidroside ultimately inhibits M1 macrophage polarization and maintains mitochondrial homeostasis after macrophage polarization by increasing mitochondrial membrane potential, decreasing ROS levels, inhibiting NF-κB activation, and in turn regulating the expression of proinflammatory factors and mitochondrial homeostasis-associated proteins.


Assuntos
NF-kappa B , Fator de Necrose Tumoral alfa , NF-kappa B/metabolismo , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Macrófagos , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase/metabolismo , Homeostase , RNA Mensageiro/metabolismo
8.
Appl Opt ; 62(16): 4203-4212, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706905

RESUMO

We propose a method for coupling a tapered optical fiber to an inverted tapered SiN waveguide by fabricating a microfiber using 3D nanoprinting lithography. The microfiber consists of three parts: a tapered cladding cap, an S-bend, and a straight part, all composed of high-refractive-index material. Light is adiabatically coupled from the tapered fiber to the printed microfiber through the cladding cap. The light is then transmitted through the S-bend and the straight part with low loss and is finally coupled to the waveguide through the evanescent field. In the simulation, our design can achieve a high coupling efficiency (TE mode) of ∼97% at a wavelength of 1542 nm with a wide bandwidth of ∼768n m at the 1-dB cutoff criterion.

9.
Drug Resist Updat ; 65: 100883, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36202008

RESUMO

AIMS: This study aimed to identify mechanisms of drug resistance to the combination of vemurafenib, irinotecan, and cetuximab (VIC) in BRAFV600E metastatic colorectal cancer (mCRC). METHODS: Forty-one patients with BRAFV600E mCRC from July 2018 and June 2020 were evaluated, with tissue and/or plasma samples collected. We profiled tissue and plasma samples using whole-exome sequencing and targeted sequencing of 425 cancer-relevant genes. Clinical cohort analysis from published studies was performed to consolidate our findings. RESULTS: BRAF mutant in baseline plasma and its dynamics are significantly associated with VIC-related response, and concurrent RNF43 mutation significantly sensitises tumour to VIC treatment. VIC resistance frequently involves genes in PI3K, MAPK pathway, and several novel resistance mechanisms such as TGFBR2 and SMAD4 mutations, and copy-number gains in PTK2, MYC, and GATA6 have been identified. We also firstly describe acquired altered genes in DNA damaging repair pathway, occurring in 33 % of patients after VIC treatment, and particularly, patients with this pre-treatment resistance subclones developed inferior responses, along with higher tumour mutation burden both at baseline and progression plasma. CONCLUSION: Analysis of ctDNA can provide novel insights into molecular resistance mechanisms to VIC in BRAFV600E mCRC patients, allowing accurate guidance for clinicians in personalised treatment strategies.


Assuntos
DNA Tumoral Circulante , Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Humanos , Cetuximab/farmacologia , Cetuximab/uso terapêutico , DNA Tumoral Circulante/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Irinotecano/farmacologia , Irinotecano/uso terapêutico , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Vemurafenib/uso terapêutico
10.
Neurobiol Dis ; 175: 105922, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371059

RESUMO

Our previous study suggests that hippocampal cysteinyl leukotriene receptor 1 (CysLT1R) could be involved in depression. Herein we hypothesize that CysLT1R may regulate depression by affecting synaptic glutamate cycling based on existence of CysLT1R in the astrocytes that participate in occurrence of depression. We found that CysLT1R expression was significantly increased in the astrocyte of chronic unpredictable mild stress (CUMS)-induced depression-like mice, CysLT1R astrocyte-specific conditional knockout (AcKO) significantly improved depression-like behaviors, as indicated by decreased immobility time in the forced swimming test and tail suspension test and increased sucrose preference in the sucrose preference test, and knockdown of CysLT1R in the astrocyte of dentate gyrus (DG), the region with the most significant increase of CysLT1R in the astrocyte of depression-like mice, produced similar effects. Correspondingly, overexpression of CysLT1R in the astrocyte of DG induced depression-like behaviors in mice. The further study showed that CysLT1R AcKO ameliorated synaptic plasticity impairment, as reflected by increased synapse, LTP and PSD95, and promoted glutamate transporter 1 (GLT-1) expression by inhibiting NF-κB p65 nuclear translocation mediated by ß-arestin2 and clatrhin, subsequently decreased glutamate in synaptic cleft and GluN2B on postsynaptic membrane in depression-like mice. The present study also showed that GLT-1 agonist or NF-κB inhibitor ameliorated depressive-like behaviors induced by overexpression of the astrocyte CysLT1R of DG. Our study demonstrated that astrocyte CysLT1R regulated depression by modulating glutamate synaptic transmission, suggesting that CysLT1R could be a potential target for developing novel drugs of anti-depression.


Assuntos
Astrócitos , Depressão , Ácido Glutâmico , Receptores de Leucotrienos , Transmissão Sináptica , Animais , Camundongos , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , NF-kappa B/metabolismo , Estresse Psicológico , Sacarose/metabolismo , Sacarose/farmacologia , Receptores de Leucotrienos/metabolismo , Depressão/metabolismo , Depressão/patologia
11.
Cancer Sci ; 113(10): 3330-3346, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35792657

RESUMO

Colon cancer is the third most common cancer and the second leading cause of cancer-related death worldwide. Dysregulated RNA splicing factors have been reported to be associated with tumorigenesis and development in colon cancer. In this study, we interrogated clinical and RNA expression data of colon cancer patients from The Cancer Genome Atlas (TCGA) dataset and the Gene Expression Omnibus (GEO) database. Genes regulating RNA splicing correlated with survival in colon cancer were identified and a risk score model was constructed using Cox regression analyses. In the risk model, RNA splicing factor peroxisome proliferator-activated receptor-γ coactivator-1α (PPARGC1) is correlated with a good survival outcome, whereas Cdc2-like kinase 1(CLK1), CLK2, and A-kinase anchor protein 8-like (AKAP8L) with a bad survival outcome. The risk model has a good performance for clinical prognostic prediction both in the TCGA cohort and the other two validation cohorts. In the tumor microenvironment (TME) analysis, the immune score was higher in the low-risk group, and TME-related pathway gene expression was also higher in low-risk group. We further verified the mRNA and protein expression levels of these four genes in the adjacent nontumor, tumor, and liver metastasis tissues of colon cancer patients, which were consistent with bioinformatics analysis. In addition, knockdown of AKAP8L can suppress the proliferation and migration of colon cancer cells. Animal studies have also shown that AKAP8L knockdown can inhibit tumor growth in colon cancer in vivo. We established a prognostic risk model for colon cancer based on genes related to RNA splicing regulation and uncovered the role of AKAP8L in promoting colon cancer progression.


Assuntos
Neoplasias do Colo , Regulação Neoplásica da Expressão Gênica , Proteínas de Ancoragem à Quinase A/genética , Proteínas de Ancoragem à Quinase A/metabolismo , Neoplasias do Colo/genética , Expressão Gênica , Humanos , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Prognóstico , Splicing de RNA/genética , Fatores de Processamento de RNA/genética , RNA Mensageiro/genética , Microambiente Tumoral
12.
Small ; 18(6): e2105923, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854565

RESUMO

In this work, a LaB6 -alloying strategy is reported to effectively boost the figure-of-merit (ZT) of Ge0.92 Bi0.08 Te-based alloys up to ≈2.2 at 723 K, attributed to a synergy of La-dopant induced band structuring and structural manipulation. Density-function-theory calculations reveal that La dopant enlarges the bandgap and converges the energy offset between the sub-valence bands in cubic-structured GeTe, leading to a significantly increased effective mass, which gives rise to a high Seebeck coefficient of ≈263 µV K-1 and in turn a superior power factor of ≈43 µW cm-1 K-2 at 723 K. Besides, comprehensive electron microscopy characterizations reveal that the multi-scale phonon scattering centers, including a high density of planar defects, Boron nanoparticles in tandem with enhanced boundaries, dispersive Ge nanoprecipitates in the matrix, and massive point defects, contribute to a low lattice thermal conductivity of ≈0.67 W m-1 K-1 at 723 K. Furthermore, a high microhardness of ≈194 Hv is witnessed in the as-designed Ge0.92 Bi0.08 Te(LaB6 )0.04 alloy, derived from the multi-defect-induced strengthening. This work provides a strategy for developing high-performance and mechanical robust middle-temperature thermoelectric materials for practical thermoelectric applications.

13.
Chem Rev ; 120(15): 7399-7515, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32614171

RESUMO

The long-standing popularity of thermoelectric materials has contributed to the creation of various thermoelectric devices and stimulated the development of strategies to improve their thermoelectric performance. In this review, we aim to comprehensively summarize the state-of-the-art strategies for the realization of high-performance thermoelectric materials and devices by establishing the links between synthesis, structural characteristics, properties, underlying chemistry and physics, including structural design (point defects, dislocations, interfaces, inclusions, and pores), multidimensional design (quantum dots/wires, nanoparticles, nanowires, nano- or microbelts, few-layered nanosheets, nano- or microplates, thin films, single crystals, and polycrystalline bulks), and advanced device design (thermoelectric modules, miniature generators and coolers, and flexible thermoelectric generators). The outline of each strategy starts with a concise presentation of their fundamentals and carefully selected examples. In the end, we point out the controversies, challenges, and outlooks toward the future development of thermoelectric materials and devices. Overall, this review will serve to help materials scientists, chemists, and physicists, particularly students and young researchers, in selecting suitable strategies for the improvement of thermoelectrics and potentially other relevant energy conversion technologies.

14.
Small ; 17(25): e2100525, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34032362

RESUMO

Mn alloying in thermoelectrics is a long-standing strategy for enhancing their figure-of-merit through optimizing electronic transport properties by band convergence, valley perturbation, or spin-orbital coupling. By contrast, mechanisms by which Mn contributes to suppressing thermal transports, namely thermal conductivity, is still ambiguous. A few precedent studies indicate that Mn introduces a series of hierarchical defects from the nano- to meso-scale, leading to effective phonon scattering scoping a wide frequency spectrum. Due to insufficient insights at the atomic level, the theory remains as phenomenological and cannot be used to quantitatively predict the thermal conductivity of Mn-alloyed thermoelectrics. Herein, by choosing the SnTe as a case study, aberration-corrected transmission electron microscopy (TEM)/scanning transmission electron microscopy (STEM) to characterize the lattice complexity of Sn1.02- x Mnx Te is employed. Mn as a "dynamic" dopant that plays an important role in SnTe with respect to different alloying levels or post treatments is revealed. The results indicate that Mn precipitates at x = 0.08 prior to reaching solubility (≈10 mol%), and then splits into MnSn substitution and γ-MnTe hetero-phases via mechanical alloying. Understanding such unique crystallography evolution, combined with a modified Debye-Callaway model, is critical in explaining the decreased thermal conductivity of Sn1.02- x Mnx Te with rational phonon scattering pathways, which should be applicable for other thermoelectric systems.

15.
Inorg Chem ; 60(18): 14165-14173, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34474565

RESUMO

Discovering high-performance near-room-temperature thermoelectric materials is extremely imperative to widen the practical application in thermoelectric power generation and refrigeration. Here, ternary Ag2Se1-xTex (x = 0.1, 0.2, 0.3, 0.4, and 0.5) materials are prepared via the wet-mechanical alloying and spark plasma sintering process to investigate their near-room-temperature thermoelectric properties. From density functional theory calculation and single-parabolic-band modeling study, we found that the reduced contribution of Se 4p orbitals to the total density of states decreases the carrier effective mass with increasing Te content, which should enhance the theoretically maximum zT. These calculation results are also verified by the experimental results. Meanwhile, complex microstructures including dislocations, nanograins, high-density boundaries, TeSe substitution, lattice distortions, and localized strain have been observed in ternary Ag2Se1-xTex. These complex microstructures strengthen phonon scattering and in turn lead to ultralow lattice thermal conductivity in the range of 0.21-0.31 W m-1 K-1 in ternary Ag2Se1-xTex at 300 K. Although the increased deformation potential suppresses the carrier mobility, benefiting from the engineered band structures and ultralow lattice thermal conductivity, a high zT of >1 can be potentially obtained in the ternary Ag2Se1-xTex with appropriate carrier concentration. This study indicates that ternary Ag2Se1-xTex is a promising candidate for near-room-temperature thermoelectric applications.

16.
J Sci Food Agric ; 101(7): 2930-2939, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33155677

RESUMO

BACKGROUND: Porphyra haitanensis now faces serious heavy metal pollution problems. Natural deep eutectic solvents (NADESs) have been recognized as a novel class of sustainable solvents, which can be used for heavy metal removal. In this study, 28 kinds of NADESs were prepared and investigated as eluent in the removal of lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), and copper (Cu) from P. haitanensis for the first time, and the adsorption mechanism of NADESs was also studied. RESULTS: The removals were greatly improved by NADESs compared with control where the removal rates of Pb, Cd, Cr, As and Cu were 17.4-87.54%, 57.54-100%, 9.8-48.59%, 21.32-78.24% and 11.68-79.73%, respectively. The optimal condition was 10% water content and solid-liquid ratio of 1:20. Moreover, the addition of 20% natural surfactant arabic gum can further increase the heavy metals removal rates of NADESs. The adsorption mechanism experiments showed that the pseudo second-order model and the Freundlich adsorption model can better explain the adsorption mechanism of NADESs on heavy metals removal. CONCLUSION: Taken together, a green and efficient method for removing heavy metals from P. haitanensis was established. © 2020 Society of Chemical Industry.


Assuntos
Química Verde/métodos , Metais Pesados/isolamento & purificação , Porphyra/química , Adsorção , Cádmio/análise , Cádmio/isolamento & purificação , Cromo/isolamento & purificação , Cobre/análise , Cobre/isolamento & purificação , Química Verde/instrumentação , Chumbo/análise , Chumbo/isolamento & purificação , Metais Pesados/análise , Solventes/química
17.
J Am Chem Soc ; 142(5): 2672-2681, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31940193

RESUMO

The coupling nature of thermoelectric properties determines that optimizing the Fermi level is the priority to achieve a net increase in thermoelectric performance. Conventionally, the carrier concentration is used as the reflection of the Fermi level in the band structure. However, carrier concentration strongly depends upon the material's effective mass, leading to that the optimal carrier concentration varies over a large scale for different materials. Herein, inspired by the big data survey, we develop a golden Seebeck coefficient range of 202-230 µV K-1 for thermoelectric semiconductors with lattice thermal conductivity of 0.4-1.5 W m-1 K-1. When the measured Seebeck coefficient reaches this range, the corresponding figure of merit is maximized. Using this approach, we exemplarily analyze the characteristics of n-type Pb1-xBixSe thermoelectric materials. With detailed electron microscopy and property characterizations, the high densities of dislocations and pores are found to be responsible for a low lattice thermal conductivity. Moreover, Bi substitution significantly tunes the Seebeck coefficient in a wide range. As a result, the Seebeck coefficient of ∼ -230 µV K-1 in Pb0.98Bi0.02Se is close to the golden range, leading to a figure of merit beyond 1.5. This finding provides an intuitive metric to determine the optimization extent of thermoelectric performance.

18.
Nanomedicine ; 28: 102219, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32474078

RESUMO

Dual-modality contrast agents for T1-weighted magnetic resonance imaging (MRI) and photoacoustic imaging have attracted substantial attention as they combine the advantages of unlimited penetration depth and high sensitivity. However, most of the reported agents are Gd-based materials that exhibit nephrotoxicity, and few studies have focused on Fe-based materials owing to their lower relaxivity. This work describes the development of an ellagic acid (EA)-Fe nanoscale coordination polymer with high longitudinal relaxivity and strong near-infrared absorption for dual-modality T1-weighted MRI and photoacoustic imaging. The longitudinal relaxivity (r1) of the prepared EA-Fe@BSA nanoparticles was 2.54 mM-1 s-1, an increase of 185% compared with previously reported gallic acid-Fe nanoparticles. Furthermore, in vitro and in vivo experiments demonstrate that the EA-Fe@BSA NPs are an excellent T1-weighted MRI and photoacoustic dual-modality contrast agent with the advantages of convenient synthesis and low toxicity, exhibiting great potential for clinical use in tumor imaging.


Assuntos
Meios de Contraste/química , Ácido Elágico/química , Compostos Férricos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Polímeros/química , Técnicas Fotoacústicas
19.
J Integr Neurosci ; 19(1): 21-29, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32259883

RESUMO

The neuroprotective role of Fructus Broussonetiae in a model of chronic cerebral hypoperfusion with cognitive decline was focused on neural plasticity and microglia/macrophage polarization. Chronic cerebral hypoperfusion was induced by bilateral common carotid artery ligation. Fructus Broussonetiae shortened escape latency and added the number of platform crossings of rats, up-regulated the expression of synaptophysin in the gray matter and increased myelin basic protein expression in the white matter. Further mechanistic experiments were conducted to examine microglia activation and M1/M2 polarization. It was shown that Fructus Broussonetiae reduced the activation of microglia revealed by decreased expression of ionized calcium-binding adapter molecule-1, inhibited M1 polarization of microglia and improved microglial M2 polarization shown by down-regulated the expression of inducible nitric oxide synthase and Fc fragment of IgG receptor IIIa and up-regulated the expression of arginase-1. In conclusion, the Chinese herb Fructus Broussonetiae can improve cognitive function following chronic cerebral hypoperfusion by down-regulating the activation of microglia, inhibiting microglial M1 polarization, and improving neural plasticity.


Assuntos
Encéfalo/efeitos dos fármacos , Broussonetia , Transtornos Cerebrovasculares/complicações , Disfunção Cognitiva/fisiopatologia , Aprendizagem em Labirinto/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Memória Espacial/efeitos dos fármacos , Animais , Encéfalo/fisiopatologia , Transtornos Cerebrovasculares/fisiopatologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Microglia/fisiologia , Ratos Sprague-Dawley
20.
Zhongguo Zhong Yao Za Zhi ; 45(23): 5804-5818, 2020 Dec.
Artigo em Zh | MEDLINE | ID: mdl-33496122

RESUMO

The purpose of the study is to analyze the outcomes of randomized controlled trial(RCT) of Chinese herbal medicine formula(CHMF) in the treatment of vascular cognitive impairment caused by cerebral small vessel disease(CSVD-VCI), and provide suggestions for future studies in this field. Three English databases, four Chinese databases, and two online registration websites of clinical trials were searched with use of the search strategy established in advance. Relevant RCTs published in recent ten years were screened, and necessary information was extracted to assess the risk of bias and analyze the outcomes of these RCTs. As a result, a total of 10 461 articles were retrieved, of which 8 681 were kept after de-duplication, and 41 RCTs were included after screening, with a generally higher risk of bias. The outcomes of included RCTs were classified into 9 categories, namely, clinical symptom outcomes, neuroimaging outcomes, neuroelectrophysiological outcomes, blood biochemical outcomes, hemorheology outcomes, physical signs, syndrome scores of traditional Chinese medicine(TCM), clinical effective rate, and safety outcomes. Among them, the most frequently reported outcomes of included RCTs were blood biochemical outcomes, and clinical symptom outcomes showed the highest reporting rate. Besides, 9 RCTs reported syndrome scores of TCM as the outcomes and illustrated corresponding evaluation criteria. The analysis showed that the application of RCT outcomes in this field had clinical rationality and limitations, and there were also some deficiencies in the trial design level, namely, no distinction between primary and secondary outcomes, insufficient blind methods, not detailed description of outcomes, disunity of evaluation tools, and despised endpoint outcomes. These limitations and deficiencies were negatively affecting the quality of RCTs of CHMF in the treatment of CSVD-VCI. Therefore, we suggest that future researchers should be well prepared in the top-level design stage, and actively construct the core outcome set of this field, so as to improve the quality of clinical trials.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa , Fitoterapia
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