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1.
Phys Chem Chem Phys ; 26(17): 13327-13334, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38639877

RESUMEN

Intrinsic half-metallic nanomaterials with 100% spin polarization are highly demanded for next-generation spintronic devices. Here, by using first-principles calculations, we have designed a class of new two-dimensional (2D) p-type half-metals, MSi2N4 (M = Al, Ga, In and Tl), which show high mechanical, thermal and dynamic stabilities. MSi2N4 not only have ultrawide electronic bandgaps for spin-up channels in the range of 4.05 to 6.82 eV but also have large half-metallic gaps in the range of 0.75 to 1.47 eV, which are large enough to prevent the spin-flip transition. The calculated magnetic moment is 1 µB per cell, resulting from polarized N1-px/py orbitals. Moreover, MSi2N4 possess robust long-range ferromagnetic orderings with Curie temperatures in the range of 35-140 K, originating from the interplay of N1-M-N1 superexchange interactions. Furthermore, spin dependent electronic transport calculations reveal 100% spin polarization. Our results highlight new promising 2D ferromagnetic half-metals toward future spintronic applications.

2.
Phys Chem Chem Phys ; 26(5): 4403-4411, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38240016

RESUMEN

Nonlinear optical (NLO) crystals based on oxides typically have wide bandgaps and large laser damage thresholds (LDTs), which are important for generating high-power and continuous terahertz radiation. Recently, a new family of NLO materials α-A2BB'O6 including Li2TiTeO6 (LTTO) with a strong second harmonic generation (SHG) efficiency of 26 × KH2PO4 (KDP) and a large LDT of 550 MW cm-2 were reported. Herein, we systematically study the electronic structures and NLO properties of α-A2BB'O6 (A = Li, Na, K; B = Ti, Zr, Hf; B' = Se, Te) to explore the relationship between the structure and SHG coefficient. First, 15 members of the A2BB'O6 family are demonstrated to be highly stable and NLO materials, excluding K2TiTeO6, K2TiSeO6 and K2ZrSeO6. Then, the electronic band structure, dipole moment and distortion of BO6/B'O6 octahedrons, SHG coefficient and terahertz absorption spectrum are calculated comprehensively with the element variation of A-site, B-site and B'-site. Finally, the magnitude of the SHG coefficient is found to be directly proportional to the value of total dipole moment and distortion, and inversely proportional to the bandgap value. Most importantly, among the A2BB'O6 materials, K2HfSeO6 shows the smallest direct bandgap of 2.99 eV, the largest SHG coefficient d33 of about 5 × LTTO and low terahertz absorbance from 0.1 to 9 THz. Our results provide new NLO crystals that may have potential application in terahertz radiation sources and other nonlinear electronics.

3.
Phys Chem Chem Phys ; 25(34): 22920-22926, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37591826

RESUMEN

Na3PS4 crystals with high ionic conductivity are promising solid-state electrolytes. Here, a novel phase of Na3PS4 (ß'-NPS) crystallizing in a cubic lattice with a space group of P4̄3m was systematically investigated using first-principles calculations. First of all, ß'-NPS is determined to be thermodynamically, dynamically and mechanically stable. The phase transition from tetragonal Na3PS4(α-NPS) to a cubic ß'-NPS system occurs at approximately 480 K, suggesting high feasibility of experimental access. Moreover, the ß'-NPS is an insulator with a large band gap of 4.05 eV and a low migration energy barrier of 0.10 eV for an interstitial Na ion. Significantly, a novel Na ion diffusion mechanism, that is, interstitial diffusion, is proposed, in contrast to traditional vacancy diffusion or kick-off diffusion as observed in most solid electrolytes. This work proposes ß'-NPS as a promising superionic conductor for sodium ion batteries and provides theoretical guidance towards designing future ideal solid-state electrolytes.

4.
Phys Chem Chem Phys ; 25(48): 32875-32882, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38051151

RESUMEN

Although the efficient separation of electron-hole (e-h) pairs is one of the most sought-after electronic characteristics of materials, due to thermally induced atomic motion and other factors, they do not remain separated during the carrier transport process, potentially leading to rapid carrier recombination. Here, we utilized real-time time-dependent density functional theory in combination with nonadiabatic molecular dynamics (NAMD) to explore the separated dynamic transport path within Ruddlesden-Popper oxysulfide perovskite Y2Ti2O5S2 caused by the dielectric layer and phonon frequency difference. The underlying origin of the efficient overall water splitting in Y2Ti2O5S2 is systematically explored. We report the existence of the bi-directional e-h separate-path transport, in which, the electrons transport in the Ti2O5 layer and the holes diffuse in the rock-salt layer. This is in contrast to the conventional e-h separated distribution with a crowded transport channel, as observed in SrTiO3 and hybrid perovskites. Such a unique feature finally results in a long carrier lifetime of 321 ns, larger than that in the SrTiO3 perovskite (160 ns) with only one carrier transport channel. This work provides insights into the carrier transport in lead-free perovskites and yields a novel design strategy for next-generation functionalized optoelectronic devices.

5.
Nano Lett ; 22(13): 5592-5599, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35729076

RESUMEN

The number of semiconducting MXenes with direct band gaps is extremely low; thus, it is highly desirable to broaden the MXene family beyond carbides and nitrides to expand the palette of desired chemical and physical properties. Here, we theoretically report the existence of the single-layer (SL) dititanium oxide 2H-Ti2O MOene (MXene-like 2D transition oxides), showing an Ising superconducting feature. Moreover, SL halogenated 2H- and 1T-Ti2O monolayers display tunable semiconducting features and strong light-harvesting ability. In addition, the external strains can induce Weyl fermions via quantum phase transition in 2H-Ti2OF2 and Ti2OCl2 monolayers. Specifically, 2H- and 1T-Ti2OF2 are direct semiconductors with band gaps of 0.82 and 1.18 eV, respectively. Furthermore, the carrier lifetimes of SL 2H- and 1T-Ti2OF2 are evaluated to be 0.39 and 2.8 ns, respectively. This study extends emerging phenomena in a rich family of 2D MXene-like MOene materials, which provides a novel platform for next-generation optoelectronic and photovoltaic fields.

6.
Br J Surg ; 108(9): 1126-1132, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34037206

RESUMEN

BACKGROUND: This study aims to assess the learning curve of robotic distal gastrectomy (RDG) and robotic total gastrectomy (RTG) for gastric cancer. METHODS: Data on consecutive patients who underwent robotic gastrectomy for gastric cancer by five surgeons between March 2010 and August 2019 at two high-volume institutions were collected. The learning curve was determined based on the analyses of operation time and postoperative complications within 30 days. Cumulative sum analysis (CUSUM) and risk-adjusted-CUSUM (RA-CUSUM) were applied to identify the turning points (TPs). RESULTS: A total of 899 consecutive patients were included. The mean number of patients needed to overcome the learning curve for operation time of RDG and RTG were 22 and 20, respectively. The number of patients needed to overcome the learning curve for postoperative complications after RDG and RTG were 23 and 18, respectively. The surgical outcomes in the post-TP group were better than in the pre-TP group and improved as surgeons' experience increased. Also, increased case numbers in RDG promoted the RTG learning process. CONCLUSION: The present study demonstrated a substantial influence of surgical cumulative volume on improved surgical outcomes in robotic gastrectomy. Increased experience in RDG may help surgeons to achieve proficiency faster in RTG.


Asunto(s)
Gastrectomía/métodos , Laparoscopía/métodos , Curva de Aprendizaje , Procedimientos Quirúrgicos Robotizados/métodos , Neoplasias Gástricas/cirugía , Humanos , Tempo Operativo , Estudios Retrospectivos
7.
Phys Chem Chem Phys ; 23(22): 12834-12841, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34060551

RESUMEN

In this study, three stable two-dimensional beryllium diphosphide (2D-BeP2) structures with the wrinkle and planar monolayers, namely MoS2-like 6[combining macron]m-BeP2 phase (1H-BeP2), pentagonal 4[combining macron]2m-BeP2 (Penta-BeP2) and planar mm2-BeP2 (Planar-BeP2), have been successfully predicted through the first-principles calculation combined with a global structure search method. The structural stabilities, mechanical properties, electron properties and superconductivities are also systematically investigated. Results indicated that the 2D MoS2-like 1H-BeP2 showed higher stability than the Penta- and Planar-BeP2 structures. The 1H-BeP2 structure possessed an intrinsic metallic characteristics with the bands crossing the Fermi level. Notably, the Penta-BeP2 is a typical semiconductor, and the planar-BeP2 is semi-metal with Dirac corn. Based on the calculation results of the electron properties, phonon properties and electron-phonon coupling (EPC), the layer 1H-BeP2 sheet is a phonon-mediated superconductor with a critical temperature (Tc) of about 1.32 K.

8.
Phys Chem Chem Phys ; 21(28): 15327-15338, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31259339

RESUMEN

Two-dimensional (2D) superconductors, which can be widely applied in optoelectronic and microelectronic devices, have gained renewed attention in recent years. Based on the crystal structure prediction method and first-principles calculations, we obtain four novel 2D tungsten boride structures of tetr-, hex-, and tri-W2B2 and hex-WB4 and investigate their bonding types, electronic properties, phonon dispersions and electron-phonon coupling (EPC). The results show that both tetr- and hex-W2B2 are intrinsic phonon-mediated superconductors with a superconducting transition temperature (Tc) of 7.8 and 1.5 K, respectively, while tri-W2B2 and hex-WB4 are normal metals. We demonstrate that carrier doping as well as biaxial strain can soften the low-frequency phonon modes and enhance the strength of the EPC. While the Tc of tetr-W2B2 can be increased to 15.4 K under a compressive strain of -2%, the Tc of hex-W2B2 can be enhanced to 5.9 K by a tensile strain of +4%. With the inclusion of spin-orbit couping (SOC), the value of Tc decreases by 38.5% in our systems. Furthermore, we explore the stabilities and mechanical properties of tetr- and hex-W2B2 and indicate that they may be prepared by growing on ZnS(100) and ZnS(111), respectively. Our findings provide novel 2D superconducting materials and will stimulate more efforts in this filed.

9.
Ultrason Imaging ; 41(1): 49-58, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30803409

RESUMEN

This retrospective study aimed to use preoperative and contrast-enhanced ultrasound (CEUS) factors to assess and reveal risk factors of early recurrence (ER) in patients with hepatocellular carcinoma (HCC). We enrolled 141 patients with primary HCC who had undergone surgical resection. The assessment of the CEUS scan includes (a) the maximum diameter of the lesion, (b) the tumor echogenicity of gray-scale ultrasound (US), (c) the morphology of the tumor, (d) the margin of the tumor, (e) the peripheral hypoechoic halo, (f) tumor necrosis, (g) nutritional arteries shown by tumors, (h) ultrasonography for diagnosis of cirrhosis, and (i) the timer on the US screen displayed the time elapsed from the saline flush and was used to determine time to washout. According to the degree of the phase, the washout rate is divided into four grades, namely, levels 1 to 4. ER is defined as the time between resection and recurrence within 12 months after surgery. Risk factors for ER HCC were analyzed. Predictors of ER on a univariate logistic regression analysis in CEUS are size, washout rate, morphology, center necrosis, and feeding artery appearing in the tumor. Multivariate analysis results indicated that feeding artery, microvascular invasion (MVI), and washout rate were independent risk factors for ER. The relative high risk of ER for washout rate 1, 2, 3, and 4 were 29.3%, 43.2%, 53.1%, and 71.4%, respectively. The appropriateness of hepatectomy in the treatment of single lesion HCC should be carefully considered when the washout rate was 4.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Medios de Contraste , Aumento de la Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Ultrasonografía/métodos , Carcinoma Hepatocelular/cirugía , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/cirugía , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
10.
Plant J ; 90(1): 147-163, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28103409

RESUMEN

Iron (Fe)-homeostasis in the plastids is closely associated with Fe transport proteins that prevent Fe from occurring in its toxic free ionic forms. However, the number of known protein families related to Fe transport in the plastids (about five) and the function of iron in non-green plastids is limited. In the present study, we report the functional characterization of Zea mays Fe deficiency-related 4 (ZmFDR4), which was isolated from a differentially expressed clone of a cDNA library of Fe deficiency-induced maize roots. ZmFDR4 is homologous to the bacterial FliP superfamily, coexisted in both algae and terrestrial plants, and capable of restoring the normal growth of the yeast mutant fet3fet4, which possesses defective Fe uptake systems. ZmFDR4 mRNA is ubiquitous in maize and is inducible by iron deficiency in wheat. Transient expression of the 35S:ZmFDR4-eGFP fusion protein in rice protoplasts indicated that ZmFDR4 maybe localizes to the plastids envelope and thylakoid. In 35S:c-Myc-ZmFDR4 transgenic tobacco, immunohistochemistry and immunoblotting confirmed that ZmFDR4 is targeted to both the chloroplast envelope and thylakoid. Meanwhile, ultrastructure analysis indicates that ZmFDR4 promotes the density of plastids and accumulation of starch grains. Moreover, Bathophenanthroline disulfonate (BPDS) colorimetry and inductively coupled plasma mass spectrometry (ICP-MS) indicate that ZmFDR4 is related to Fe uptake by plastids and increases seed Fe content. Finally, 35S:c-Myc-ZmFDR4 transgenic tobacco show enhanced photosynthetic efficiency. Therefore, the results of the present study demonstrate that ZmFDR4 functions as an iron transporter in monocot plastids and provide insight into the process of Fe uptake by plastids.


Asunto(s)
Deficiencias de Hierro , Hierro/metabolismo , Proteínas de Plantas/metabolismo , Plastidios/metabolismo , Zea mays/metabolismo , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Zea mays/genética
11.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 46(2): 192-197, 2017 03 25.
Artículo en Zh | MEDLINE | ID: mdl-28752712

RESUMEN

Objective: To investigate the effect of glycyrrhizinate and phospholipids (DGPL) complex on inflammatory gene expression in cell inflammation model induced by palmitic acid (PA). Methods: Huh7 cells were divided into control, PA and PA+DGPL groups. For control group, cells were treated with BSA; for PA group, cells were incubated with 0.2 mmol/L saturated fatty acid PA, PA+DGPL group was given 20 µmol/L or 100 µmol/L DGPL in addition to 0.2 µmol/L PA. After 24 h, the expression of inflammation-related genes COX-2 and iNOS and endoplasmic reticulum (ER) stress-related gene GRP78 was determined by RT PCR. Oil red staining was conducted to observe the effect of DGLP on steatosis. Results: Compared with control group, the expression of COX-2, iNOS and GRP78 in PA group was enhanced to 6.07±0.73(P<0.05), 3.18±0.91 (P<0.01) and 3.21±1.00(P<0.05), respectively. Compared to control group, the expression of COX-2,iNOS and GRP78 in 100 µmol/L DGPL group was reduced to 2.40±0.76, 1.60±0.49 and 1.17 ±0.42 (P<0.05); and 20 µmol DGPL had similar inhibition effect on COX-2 and iNOS elevation induced by PA (P<0.01, P<0.05 respectively). In addition, DGLP enhances the steatosis of Huh7 cells as demonstrated by oil red staining. Conclusion: PA can induce the up-regulated expression of inflammation associated genes COX-2, iNOS and ER stress-associated gene GRP78 in Huh7 cells. DGPL is able to protect Huh7 cells from PA induced inflammatory gene expression and the beneficial effect may be partially due to its unsaturated phospholipid component, which may improve ER stress and enhance steatosis.


Asunto(s)
Regulación de la Expresión Génica , Ácido Glicirrínico , Inflamación , Ácido Palmítico , Fosfolípidos , Línea Celular , Chaperón BiP del Retículo Endoplásmico , Hígado Graso/fisiopatología , Regulación de la Expresión Génica/efectos de los fármacos , Ácido Glicirrínico/farmacología , Proteínas de Choque Térmico/genética , Humanos , Inflamación/inducido químicamente , Fosfolípidos/farmacología
12.
J Phys Chem Lett ; 15(28): 7191-7198, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38968446

RESUMEN

We investigate the electronic structure and linear and nonlinear [second-harmonic generation (SHG)] spectra of the NbOCl2 monolayer, bilayer, and bulk by using a real-time first-principles approach based on many-body theory. First, the interlayer couplings between NbOCl2 layers are very weak, due to the relatively large interlayer distance, saturation of the p orbital of Cl atoms, and high degree of localization of charge density around the Nb atom for both the lowest conduction band and the highest valence band. Second, the quasiparticle gaps and exciton binding energy for the three systems show layer-dependent features and decrease with an increase in layer thickness. Most importantly, the linear and SHG spectra of the NbOCl2 monolayer, bilayer, and bulk are dominated by strong excitonic resonances and exhibit layer-independent features due to the weak interlayer couplings. Our findings demonstrate that excitonic effects should be included in studying the optical properties of not only two-dimensional materials but also layered bulk materials with weak interlayer couplings.

13.
J Phys Chem Lett ; 15(28): 7221-7227, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38975710

RESUMEN

Intentional distortions of [BX6] octahedra within perovskite structures have been recognized as a potent strategy for precise band gap adjustments and optimization of their photovoltaic properties, yet information regarding charge carrier dynamics linked to octahedral distortion under ambient conditions for chalcogenide perovskites remains limited. In this study, we utilize ab initio nonadiabatic molecular dynamics to explore the dynamics of photogenerated carriers in a representative two-dimensional Ba3Zr2S7 material in the Ruddlesden-Popper phase. The theoretical results highlight the influence of octahedral rotation on the materials' stability and carrier recombination lifetime of the system. Specifically, the octahedrally rotating P42/mnm phase exhibits a prolonged nonradiative carrier recombination lifetime attributed to the stabilized electron-phonon coupling. These findings offer valuable insights into the fundamental physical characteristics of imposed octahedral distortion and its potential for optimizing the optoelectronic performance of 2D Ruddlesden-Popper Ba-Zr-S chalcogenide materials.

14.
J Phys Chem Lett ; 15(32): 8360-8366, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39113239

RESUMEN

The continuous pursuit of novel two-dimensional (2D) materials with intriguing properties has been a driving force in advancing various scientific and technological frontiers. Here, based on a wide range of first-principles calculations, we predicted the existence of a novel family of 2D transition-metal oxides, the Ti3O MOenes (MXene-like 2D transition oxides), and determined its distinctive electronic and topological properties. A pair of 2D antiferromagnetic (AFM) Dirac points precisely located at the Fermi level in the absence of spin-orbit coupling (SOC) is observed in the 1T-Ti3O monolayer. Moreover, upon halogenation on a bare monolayer, 1T-Ti3OCl3 and 1T-Ti3OBr3 monolayers display the quantum spin Hall (QSH) effect with nontrivial helical edge states within the gapless bulk states. Specifically, single layer 1T-Ti3OF3 behaves as an indirect semiconductor with a gap of 0.81 eV, exhibiting a strong light-harvesting capability. The indirect-gap feature can be switched to a direct one by only exerting a small tensile strain of 1.5%. These findings broaden emerging phenomena in a rich family of MOenes, suggesting a novel platform for the development of next-generation nanodevices.

15.
Heliyon ; 10(17): e37012, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39319137

RESUMEN

Background: Adenylyl cyclase (AC) isoforms played a key role in the multiple cancer pathology, However, the expression, prognostic value and function of ADCY5 in Glioblastoma (GBM) have not been reported yet. This research intends to discover the expression, epigenetic alteration and biological function of ADCY5 in GBM and its value on patients' prognosis. Methods: ① Transcriptional level, epigenetic alteration, prognostic value and molecular network of ADCY5 were analyzed by using of public online datasets. ② The mRNA expression profile of ADCY5 was explored by using GEPIA database and protein expression levels were detected by HPA Database. ③ The prognostic value of ADCY5 was determined by Kaplan-Meier Plotter, GEPIA and CGGA database. ④ The epigenetic characteristics of ADCY5 were determined by DiseaseMeth database. ⑤ Identification of genes co-expressed with ADCY5 and potential mechanism analyses were performed by using DAVID cBioPorta and STRING. ⑥ Reverse transcription-polymerase chain reaction (RT-PCR), cell counting kit-8 (CCK-8), colony formation, wound-healing scratch and transwell assay were applied to detect relative mRNA expression and biological function of ADCY5 in GMB cells. Results: ADCY5 mRNA and protein were downregulated in GBM compared with normal tissues. Analysis of the genetics and epigenetics of ADCY5 suggested that its expression was negatively correlated with DNA methylation. High expression of ADCY5 was significantly associated with age, grade, IDH mutation, 1p19q_codeletion, radiotherapy and chemotherapy and acted as an independent prognostic factor in GBM. ADCY5 mRNA also down-expressed in GBM cell lines and re-expressed of ADCY5 could inhibit cell proliferation, viability, migration/invasion and epithelial-mesenchymal transition (EMT) in vitro. In the analysis of genes co-expressed with ADCY5, we found that cAMP/AKT pathway, cGMP-PKG pathway, Wnts pathway were dissimilarly enriched. Conclusion: Our study indicated that ADCY5 could act as an epigenetic biomarker in GBM, as well as a prognosis target in patients with GBM.

16.
J Tradit Chin Med ; 44(4): 670-679, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39066527

RESUMEN

OBJECTIVE: To investigate the effects of luteolin on chronic unpredictable mild stress (CUMS)-induced depressive rats and corticosterone (CORT)-induced depressive primary hippocampal neurons, and to elucidate the mechanism behind the action. METHODS: The antidepressant mechanism of luteolin was studied by using CUMS rat model and primary hippocampal neurons in fetal rats. In vivo, novelty suppressed feeding, open-field and sucrose preference tests as well as Morris water maze were evaluated. The content of brain derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), norepinephrine (NE), and dopamine (DA) in serum were detected by enzyme-linked immunosorbent assay. The mechanisms of luteolin were explored based on neurotrophin and hippocampal neurogenesis, and proliferation. Survival of the septo-temporal axis in hippocampus was assayed using the 5-bromo-2-deoxyuridine (BrdU), the expression of BDNF, neurotrophin-3 (NT-3), and nerve growth factor (NGF) in hippocampus dentate gyrus region were measured by Western-blotting. In vitro, BDNF, NT-3, tropomyosin receptor kinase B (TrkB), and phosphorylated cyclic adenosine monophosphate responsive element binding protein (p-CREB) were detected through the high content analysis (HCA) to investigate neurotrophin and apoptosis. RESULTS: Induction of CUMS in rats induced depressive symptoms, while luteolin significantly enhanced sucrose consumption, decreased feeding latency, increased locomotor activity, escape latency, distance of target quadrant and regulated the content of depressive-like biomarkers. Histology analysis revealed that luteolin increased the abundance of new born neurons that had been labeled with BrdU, BrdU + neuronal nuclear antigen, and BrdU + doublecortin in septo-temporal axis of S2 (mid-septal) and T3 (mid-temporal). Moreover, expression of BDNF, NT-3, and NGF increased significantly in the septo-temporal axis of S2 and T3. HCA showed increased expression of BDNF, NT-3, TrkB and p-CREB in primary hippocampal neurons. CONCLUSION: The results provided direct evidence that luteolin has an antidepressant effect and could effectively promote the regeneration of the septotemporal axis nerve and hippocampal neuronutrition, which suggested that the antidepressant effect of luteolin may be related to hippocampal neurogenesis.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Hipocampo , Luteolina , Neurogénesis , Neuronas , Ratas Sprague-Dawley , Animales , Luteolina/farmacología , Ratas , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Neurogénesis/efectos de los fármacos , Masculino , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Humanos , Estrés Psicológico/fisiopatología , Estrés Psicológico/tratamiento farmacológico , Femenino , Depresión/tratamiento farmacológico , Depresión/metabolismo , Depresión/fisiopatología , Antidepresivos/farmacología , Neurotrofina 3/metabolismo , Neurotrofina 3/genética
17.
Photoacoustics ; 32: 100535, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37519337

RESUMEN

In photoacoustic (PA) reconstruction, spatial constraints or real-time system requirements often result to sparse PA sampling data. For sparse PA sensor data, the sparse spatial and dense temporal sampling often leads to poor signal continuity. To address the structural characteristics of sparse PA signals, a data interpolation algorithm based on extremum-guided interpolation is proposed. This algorithm is based on the continuity of the signal, and can complete the estimation of high sampling rate signals without complex mathematical calculations. PA signal data is interpolated and reconstructed, and the results are evaluated using image quality assessment methods. The simulation and experimental results show that the proposed method performs better than several typical algorithms, effectively restoring image details, suppressing the generation of artifacts and noise, and improving the quality of PA reconstruction under sparse sampling.

18.
J Colloid Interface Sci ; 652(Pt A): 627-635, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37586949

RESUMEN

Lithium (Li)-rich ternary alloy, comprising a multi-alloy phase as the built-in three-dimensional (3D) framework and a Li metal phase as a reversible Li reservoir, is a promising high-energy-density anode for rechargeable Li metal batteries. The introduction of metal/metalloid components to the alloy can effectively regulate Li deposition and maintain the dimensional integrity of the Li anode. Herein, the lithium-copper-zinc (Li-Cu-Zn) ternary alloy, as a new type of alloy anode, is synthesized via a facile thermal melting method. The fully delithiated 3D scaffold comprised two Cu-Zn alloy phases named CuZn and CuZn5. These alloy phases exhibit higher lithiophilicity and structural stability than Li-Zn and Li-Cu alloys. Moreover, the CuZn phase is electrochemically inert, ensuring the geometric stability of the anode, while the CuZn5 phase can readily undergo alloying reaction with Li to form the LiZn phase, thereby facilitating uniform Li nucleation and deposition. The hybridized multiphase alloy structure and specific energy storage mechanism of the Cu-Zn based alloy scaffold in the ternary alloy anode facilitate dendrite-free Li deposition and prolonged cycle lifetime. The Li metal full battery based on lithium iron phosphate (LiFePO4) cathode exhibits high cycling stability with high-capacity retention of 95.4% after 1000 cycles at 1C.

19.
Micromachines (Basel) ; 14(2)2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36838105

RESUMEN

Bulk III-nitride materials MN (M = Al, Ga and In) and their alloys have been widely used in high-power electronic and optoelectronic devices, but stable two-dimensional (2D) III-nitride materials, except h-BN, have not been realized yet. A new kind of 2D III-nitride material M2Si2N4 (M = Al, Ga and In) is predicted by choosing Si as the appropriate passivation element. The stability, electronic and optical properties of 2D M2Si2N4 materials are studied systematically based on first-principles calculations. The results show that Al2Si2N4 and Ga2Si2N4 are found to be indirect bandgap semiconductors, while In2Si2N4 is a direct bandgap semiconductor. Moreover, Al2Si2N4 and In2Si2N4 have good absorption ability in the visible light region, while Ga2Si2N4 is an ultraviolet-light-absorbing material. Furthermore, the carrier lifetimes of Ga2Si2N4 and In2Si2N4 are as large as 157.89 and 103.99 ns, respectively. All these desirable properties of M2Si2N4 materials make them attractive for applications in electronics and photoelectronics.

20.
J Phys Chem Lett ; 14(40): 9075-9081, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37788153

RESUMEN

The search for lead-free perovskite materials has triggered intensive interest. Here, we study the electronic structures and optical properties of cation-deficient Ruddlesden-Popper oxysulfide perovskites Ln2Ti2O5S2 (Ln = Sc, Y, or La), with a tunable band gap of 1.45-2.1 eV and a small exciton binding energy of ∼0.1 eV, among which Y2Ti2O5S2 has been synthesized experimentally. Sc2Ti2O5S2 possesses the largest light absorbance in the visible region. We further rationalize the light absorption via the transition dipole moment and suggest potential applications of Sc2Ti2O5S2 in solar cells and Y2Ti2O5S2 and La2Ti2O5S2 in water splitting. In addition, this family exhibits small effective masses within the x-y plane and large ones along the z direction. Most importantly, electron gas-like carrier behaviors are observed within the Ti-O bond region, offering a diffusion channel for electron transport. These findings greatly advance our understanding of lead-free perovskites and offer a novel material platform for future optoelectronic devices.

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