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Anhydrous silicophosphoric acid glass with an approximate composition of H5 Si2 P9 O29 was synthesized and its thermal and proton-conducting properties were characterized. Despite exhibiting a glass transition at 192 °C, the supercooled liquid could be handled as a solid up to 280 °C owing to its high viscosity. The glass and its melt exhibited proton conduction with a proton transport number of â¼1. Although covalent O-H bonds were weakened by relatively strong hydrogen bonding, the proton conductivity (4×10-4 â S cm-1 at 276 °C) was considerably lower than that of phosphoric acid. The high viscosity of the melt was due to the tight cross-linking of phosphate ion chains by six-fold-coordinated Si atoms. The low proton conductivity was attributed to the trapping of positively charged proton carriers around anionic SiO6 units (expressed as (SiO6/2 )2- ) to compensate for the negative charges.
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Vidro , Prótons , Condutividade Elétrica , Vidro/química , Ligação de HidrogênioRESUMO
CONTEXT: Pomelo peel oil (PPO) [Citrus maxima (Burm.) Merr. (Rutaceae)] is reported to possess antioxidant and antimelanogenic activities. OBJECTIVE: To investigate the effect of PPO [Citrus maxima (Burm.) Merr. cv. Shatian Yu] on tumour necrosis factor-α (TNF-α)-induced necroptosis in cerebral ischaemia-reperfusion injury (CIRI) after cardiac arrest (CA). MATERIALS AND METHODS: Male Sprague Dawley rats were randomly assigned to six groups: sham group, PP0-L (10 mg/kg), PPO-M (20 mg/kg), PPO-H (40 mg/kg) and two control groups (CA, 0.9% saline; Gly, 10% glycerol). All drugs were administered intravenously to the CA/CPR rats within 10 min after return of spontaneous circulation (ROSC). After 24 h, rats were assessed for neuronal injury via the neurological deficit score (NDS), cerebral cortex staining and transmission electron microscopy (TEM) and expression levels of TNF-α and necroptosis-related proteins by immunoreactivity staining and western blotting. RESULTS: Compared to those in the sham group (survival rate, 100% and NDS, 80), the survival rate and NDS were significantly reduced in the model groups (CA, 56.25%, 70; Gly, 62.5%, 71; PPO-L, 75%, 72; PPO-M, 87.5%, 75; PPO-H, 81.25%, 74). In the PPO-M group, Nissl bodies were significantly increased (43.67 ± 1.906 vs. 17 ± 1.732), the incidence of pathomorphological injury was lower and the necroptosis markers (TNF-α, RIPK1, RIPK3, p-MLKL/MLKL) expression was downregulated compared to those in the CA group (p < 0.05). DISCUSSION AND CONCLUSIONS: The neuroprotective effects of PPO in the CA rats suggested that PPO possibility as a health product enhances the resistance ability against brain injury for humans.
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Citrus/química , Parada Cardíaca/tratamento farmacológico , Óleos de Plantas/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Parada Cardíaca/fisiopatologia , Masculino , Necroptose/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Óleos Voláteis/administração & dosagem , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Óleos de Plantas/administração & dosagem , Óleos de Plantas/isolamento & purificação , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/fisiopatologia , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/administração & dosagemRESUMO
The development of an unconventional synthesis method has a large potential to drastically advance materials science. In this research, a new synthesis method based on a solid-state electrochemical reaction was demonstrated, which can be made available for intercalation and ion substitution. It was referred to as proton-driven ion introduction (PDII). The protons generated by the electrolytic dissociation of hydrogen drive other monovalent cations along a high electric field in the solid state. Utilizing this mechanism, Li+, Na+, K+, Cu+, and Ag+ were intercalated into a layered TaS2 single crystal while maintaining high crystallinity. This liquid-free process of ion introduction allows the application of high voltage around several kilovolts to the sample. Such a high electric field strongly accelerates ion substitution. Actually, compared to conventional solid-state reaction, PDII introduced 15 times the amount of K into Na super ionic conductor (NASICON)-structured Na3-xKxV2(PO4)3. The obtained materials exhibited a thermodynamically metastable phase, which has not been reported so far. This concept and idea for ion introduction is expected to form new functional compounds and/or phases.
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Due to the spontaneous transport of small-sized cations and redox reactions under open circuit conditions, the currently reported coloring electrochromic devices (ECDs) may self-bleach easily. The resulting ECDs exhibit poor open-circuit memory, which limits their applications in static display advertisement. By constructing energy barriers to effectively control small-sized cation transport, the redox reaction could be suppressed, thereby inhibiting the self-bleaching of ECDs. In this study, phosphate glass is used as an electrolyte to construct high-energy barriers. Sodium ions in phosphate glass absorb external heat to cross energy barriers and become conductive charge carriers. In this case, the electrochromism of ECDs is allowed. On the contrary, after the absorbed heat energy is released, sodium ions are immediately trapped by oxygen ions in the PO4 unit, becoming frozen ions. At this point, the electrochromization of ECDs is prohibited. Based on the ionic conductive feature of phosphate glass, ECDs absorb heat and are colored by applying an electric field first. Then, ECDs release the thermal energy and the sodium ions transport in the electrolyte is blocked to cut off the self-bleaching pathway. The prepared inorganic all-solid-state ECDs maintained the colored state for several months using the method mentioned above, which solved the problem of the poor open-circuit memory of ECDs.
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Many brain functions that underlie behavior, cognition, and emotions vary with age, as does susceptibility to neuropsychological disorders. The expression of specific genes that are involved in these functions, such as the genes encoding for oxytocin, its receptors, and apolipoprotein D, varies with age across different brain regions. The cannabinoid 1 receptor (CB1 R) is one of the most widely spread G-protein coupled receptors in the central nervous system and is increasingly recognized for its important contribution to various brain functions. Although changes in CB1 R expression with age have been reported in the male mouse brain, they have not been well investigated in the female brain. Here, we used fluorescence in situ hybridization to target CB1 R mRNA in the whole brains of female C57BL/6J mice aged 4, 6, 12, 52 (12 months) and 86 weeks (20 months), and quantified CB1 R-positive cells in 36 brain regions across the whole brain. The results showed that CB1 R-positive cells number changed with age. Specifically, CB1 R expression increased with age in some subregions of the cortex, decreased with age in the lateral septal area, and reached its lowest level at 52 weeks in the thalamus, hypothalamus, and hindbrain subregions. Cluster analysis revealed that some brain regions shared similar temporal characteristics in CB1 R-positive cell number across the lifespan. Our results provide evidence that investigation of the neural basis of age-related characteristics of female brain functions is not only warranted but required.
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Canabinoides , Longevidade , Animais , Camundongos , Masculino , Feminino , Receptores de Canabinoides/metabolismo , Camundongos Endogâmicos C57BL , Hibridização in Situ Fluorescente , Encéfalo/metabolismo , RNA Mensageiro/metabolismo , Canabinoides/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismoRESUMO
Background and purpose: The differential diagnosis between solid glioma and brain inflammation is necessary but sometimes difficult. We assessed the effectiveness of multiple diffusion metrics of diffusion-weighted imaging (DWI) in differentiating solid glioma from brain inflammation and compared the diagnostic performance of different DWI models. Materials and methods: Participants diagnosed with either glioma or brain inflammation with a solid lesion on MRI were enrolled in this prospective study from May 2016 to April 2023. Diffusion-weighted imaging was performed using a spin-echo echo-planar imaging sequence with five b values (500, 1,000, 1,500, 2000, and 2,500 s/mm2) in 30 directions for each b value, and one b value of 0 was included. The mean values of multiple diffusion metrics based on diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), mean apparent propagator (MAP), and neurite orientation dispersion and density imaging (NODDI) in the abnormal signal area were calculated. Comparisons between glioma and inflammation were performed. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) of diffusion metrics were calculated. Results: 57 patients (39 patients with glioma and 18 patients with inflammation) were finally included. MAP model, with its metric non-Gaussianity (NG), shows the greatest diagnostic performance (AUC = 0.879) for differentiation of inflammation and glioma with atypical MRI manifestation. The AUC of DKI model, with its metric mean kurtosis (MK) are comparable to NG (AUC = 0.855), followed by NODDI model with intracellular volume fraction (ICVF) (AUC = 0.825). The lowest value was obtained in DTI with mean diffusivity (MD) (AUC = 0.758). Conclusion: Multiple diffusion metrics can be used in differentiation of inflammation and solid glioma. Non-Gaussianity (NG) from mean apparent propagator (MAP) model shows the greatest diagnostic performance for differentiation of inflammation and glioma.
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FeCl3-mediated oxidative cyclization was successfully used to construct an extended thiophene-pendant pyrene skeleton and synthesize a novel thiophene-fused polycyclic aromatic (THTP-C) with a tetracene core. The identity of the compound was confirmed by ¹H-NMR, ¹³C-NMR, MS, and elemental analysis. Meanwhile, a single crystal of THTP-C was obtained and analyzed by X-ray single-crystal diffraction. THTP-C has a "saddle" shaped π-conjugated 1-D supramolecular structure, and favors highly ordered self-assembly by π-π interactions as evidenced by its concentration-dependent ¹H-NMR spectra in solution. The optical properties of THTP-C were investigated by ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy and its electrochemical properties were investigated by cyclic voltammetry (CV). The relatively large band gap (2.86 eV), low E(HOMO) level (-5.64 eV) and intermolecular π-π interactions imply that THTP-C has a high stability against photo-degradation and oxidation, and may be a promising candidate for stable hole-transporting materials.
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Naftacenos/química , Naftacenos/síntese química , Tiofenos/química , Cristalografia por Raios X , Eletroquímica , Modelos Moleculares , Ressonância Magnética Nuclear BiomolecularRESUMO
YxVO4: 0.01Dy3+ and Y0.99-x V04: 0.01Dy3+, xBi3+ phosphors were synthesized by chemical coprecipitation method. Their crystal structure, micromorphology and photoluminescence (PL) properties were investigated by X-ray diffraction (XRD), scan electron microscopy (SEM) and spectrofluorometer. YxVO4: 0.01Dy3+ and Y0.99--xVO4: 0.01Dy3+, xBi3+ phosphors have a broad excitation band from about 250 to 350 nm including a strongest peak at about 310 nm. Under its excitation, the emission spectra exhibits two sharp peaks, one of which centered at about 483 nm for 4F9/2-->6H15/2 transition of Dy3+ and the other at about 574 nm due to the 4F9/2-->6 H13/2 transition of Dy+. For YxVO4: 0.01Dy3+, (x = 0.94, 0.97, 0.99, 1.01, 1.03) phosphor, with increasing value of x, the body color of phosphor changes from yellow to white and the strongest peak in the excitation spectra shifts a little to shorter wavelength. It is detrimental to luminous intensity when Y3+ content deviates stoichiometric ratio. For Y0.99--x VO4: 0.01Dy3+, xBi3+ (x = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25) phosphor, the samples have extraneous bismuth vanadium oxide phase except for the major tetragonal zircon structure when x > or = 0.20. With increasing value of x, the band edge in the excitation spectra shifts to longer wavelength, the excitation intensity and luminous intensity increase early and decrease late. When the value of x is 0.01, the intensities increase evidently. In addition, the influence of Y3+ or Bi3+ on the color temperature of emission and micromorphology of YVO4:Dy3+ is slight.
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Animal behavior usually has a hierarchical structure and dynamics. Therefore, to understand how the neural system coordinates with behaviors, neuroscientists need a quantitative description of the hierarchical dynamics of different behaviors. However, the recent end-to-end machine-learning-based methods for behavior analysis mostly focus on recognizing behavioral identities on a static timescale or based on limited observations. These approaches usually lose rich dynamic information on cross-scale behaviors. Here, inspired by the natural structure of animal behaviors, we address this challenge by proposing a parallel and multi-layered framework to learn the hierarchical dynamics and generate an objective metric to map the behavior into the feature space. In addition, we characterize the animal 3D kinematics with our low-cost and efficient multi-view 3D animal motion-capture system. Finally, we demonstrate that this framework can monitor spontaneous behavior and automatically identify the behavioral phenotypes of the transgenic animal disease model. The extensive experiment results suggest that our framework has a wide range of applications, including animal disease model phenotyping and the relationships modeling between the neural circuits and behavior.
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Comportamento Animal/fisiologia , Fenômenos Biomecânicos/fisiologia , Proteínas dos Microfilamentos/genética , Movimento/fisiologia , Proteínas do Tecido Nervoso/genética , Animais , Aprendizado de Máquina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravação em Vídeo/métodosRESUMO
The NLR family pyrin domain-containing 3 (NLRP3) inflammasome, which is composed of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC) and pro-caspase-1 protein complexes, is activated by the reactive oxygen species (ROS) that are associated with ischemia-reperfusion (I/R) and are involved in brain damage. Pomelo peel oil (PPO) exhibits antioxidant activity. However, it is unclear whether PPO is able to attenuate NLRP3 inflammasome-induced inflammation and pyroptosis. Healthy male Sprague-Dawley rats were subjected to 7 min of cardiac arrest via trans-esophageal electrical stimulation, followed by cardiopulmonary resuscitation (CPR). The rats were then treated with PPO prior to reperfusion for 24 h. Hematoxylin and eosin staining was used to evaluate brain tissue and cell damage. In the brain tissues, reactive oxygen species (ROS) were assayed, immunofluorescence was used to analyze the expression of NLRP3 and western blotting was performed to determine the expression levels of neuroenolase (NSE), NF-κB, interleukin-1ß (IL-1ß), gasdermin D (GSDMD) and the NLRP3 inflammasome. Treatment of the rats with PPO significantly decreased the pathological damage of the brain tissue and reduced the expression of NSE, production of ROS and secretion of NF-κB, NLRP3, IL-1ß and GSDMD. In conclusion, these results demonstrate the ability of PPO to protect the brain against I/R injury in rats after CPR by a mechanism involving inhibition of the inflammation and pyroptosis mediated by NLRP3 inflammasome activation.
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BACKGROUND: Restoration of blood flow during ischemic stroke leads to Cerebral Ischemia- Reperfusion Injury (CIRI) by activating neuroinflammatory cascades. Pomelo Peel Volatile Oil (PPVO) extracted from Citrus maxima (Burm.) from the genus Rutaceae, comprises some antiinflammatory ingredients, such as limonene and ß-myrcene. OBJECTIVE: The present study aimed to investigate the potential effect of PPVO on alleviating CIRI related to the Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) pathway. METHODS: Transient middle cerebral artery occlusion/reperfusion (tMCAO/R) was performed on 65 rats, which were then distributed into five groups (n = 13/group) depending on the intervention they received: Normal Saline (NS) group, normal Glycerin (GL) group, low-dose PPVO (LP, 10mg/kg) group, high-dose PPVO (HP, 30 mg/kg) group, and Sham-operated (SH) group. Neurological Deficit Scores (NDSs) and histological changes were evaluated. Infarct volumes were measured by 2,3,5- Triphenyltetrazolium Chloride (TTC) staining. The expression of TLR4 and neutrophil infiltration were detected by Immunofluorescence (IF) staining. Moreover, the downstream molecules of the TLR4/NF-κB signaling pathway, such as IL-6, IL-1ß, TNF-α, p-IκB/IκB, and p-NF-κB p65/NF-κB p65 were analyzed by Western Blot (WB). RESULTS AND DISCUSSION: The results showed that PPVO (30 mg/kg) significantly decreased infarct volumes, improved neurological deficits and pathologic changes, inhibited TLR4/NF-κB signaling pathway suppressed neutrophil infiltration, and suppressed pro-inflammatory cytokine release. CONCLUSION: It can be concluded that PPVO may alleviate neuroinflammation and protect against CIRI via inhibiting the TLR4/NF-κB signaling pathway.
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Isquemia Encefálica , Óleos Voláteis , Traumatismo por Reperfusão , Animais , Isquemia Encefálica/tratamento farmacológico , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Reperfusão , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais , Receptor 4 Toll-LikeRESUMO
BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) is the leading cause of poor neurological prognosis after cardiopulmonary resuscitation (CPR). We previously reported that the extracellular signal-regulated kinase (ERK) activation mediates CIRI. Here, we explored the potential ERK/calpain-2 pathway role in CIRI using a rat model of cardiac arrest (CA). METHODS: Adult male Sprague-Dawley rats suffered from CA/CPR-induced CIRI, received saline, DMSO, PD98059 (ERK1/2 inhibitor, 0.3 mg/kg), or MDL28170 (calpain inhibitor, 3.0 mg/kg) after spontaneous circulation recovery. The survival rate and the neurological deficit score (NDS) were utilized to assess the brain function. Hematoxylin stain, Nissl staining, and transmission electron microscopy were used to evaluate the neuron injury. The expression levels of p-ERK, ERK, calpain-2, neuroinflammation-related markers (GFAP, Iba1, IL-1ß, TNF-α), and necroptosis proteins (TNFR1, RIPK1, RIPK3, p-MLKL, and MLKL) in the brain tissues were determined by western blotting and immunohistochemistry. Fluorescent multiplex immunohistochemistry was used to analyze the p-ERK, calpain-2, and RIPK3 co-expression in neurons, and RIPK3 expression levels in microglia or astrocytes. RESULTS: At 24 h after CA/CPR, the rats in the saline-treated and DMSO groups presented with injury tissue morphology, low NDS, ERK/calpain-2 pathway activation, and inflammatory cytokine and necroptosis protein over-expression in the brain tissue. After PD98059 and MDL28170 treatment, the brain function was improved, while inflammatory response and necroptosis were suppressed by ERK/calpain-2 pathway inhibition. CONCLUSION: Inflammation activation and necroptosis involved in CA/CPR-induced CIRI were regulated by the ERK/calpain-2 signaling pathway. Inhibition of that pathway can reduce neuroinflammation and necroptosis after CIRI in the CA model rats.
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Isquemia Encefálica/imunologia , Calpaína/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Parada Cardíaca/imunologia , Traumatismo por Reperfusão/imunologia , Animais , Calpaína/imunologia , Dipeptídeos/farmacologia , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Flavonoides/farmacologia , Inflamação/imunologia , Masculino , Necroptose , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
The cannabinoid 1 receptor (CB1 R) is the most abundant G protein-coupled receptor in the brain and plays crucial roles in emotion and behavior by modulating or mediating synaptic transmission and plasticity. Differences in CB1 R density between male and female rodents may be associated with distinct behavioral phenotypes. In the rat brain, CB1 R expression is significantly lower in the prefrontal cortex and amygdala of estrus females than in males. However, differences in CB1 R distribution due to sex over the whole mouse brain are still largely unknown. Here, we systemically investigated the expression of CB1 R mRNA in the brains of both male and female adult C57BL/6J mice using fluorescence in situ hybridization. There were significantly more CB1 R positive cells in males than in females in the orbital cortex, insular cortex, cingulate cortex, piriform cortex, secondary visual cortex, caudate putamen (striatum), and ventral hippocampal CA1. There were significantly more CB1 R mRNA cells in females than males in the fornix and dorsal hypothalamus. However, in some regions, strong hybridization signals without sex differences were detected, such as in the motor cortex, septum, medial habenular nucleus, and inferior colliculus. Moreover, female mice displayed different CB1 R mRNA expression patterns in the medial amygdala, basolateral amygdala, and parabrachial nucleus during different phases of the estrous cycle. These findings provide a basis for understanding sexual dimorphism in physiological and pathological brain functions related to CB1 R.
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Encéfalo/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro , Caracteres SexuaisRESUMO
Two-dimensional (2D) black phosphorene (BP) field-effect transistors (FETs) show excellent device performance but suffer from serious instability under ambient conditions. Isoelectronic 2D germanium selenide (GeSe) shares many similar properties with 2D BP, such as high carrier mobility and anisotropy, but is stable under ambient conditions. Herein, we explore the quantum transport properties of sub-5 nm ML GeSe MOSFETs using first-principles quantum transport simulation. A p-type (zigzag-directed) device is superior to other types (n- and p-type armchair-directed and n-type zigzag-directed). The on-state current of p-type devices (zigzag-directed), even at a 1 nm gate-length, can fulfill the requirements of high-performance applications for the next decade in the International Technology Roadmap for Semiconductors (ITRS, 2013 version). To the best of our knowledge, these ML GeSe MOSFETs have the smallest gate-length that can fulfill the ITRS HP on-state current requirements among reported 2D material FETs.
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OBJECTIVES: Dynamin-related protein 1 (Drp1) mediates mitochondrial fission and triggers NLRP3 inflammasome activation. FK866 (a NAMPT inhibitor) exerts a neuroprotective effect in ischemia/reperfusion injury through the suppression of mitochondrial dysfunction. We explored the effects of FK866 on pyroptosis and inflammation mediated by Drp1 in a cardiac arrest/cardiopulmonary resuscitation (CA/CPR) rat model. METHODS: Healthy male Sprague-Dawley rats were subjected to 7 min CA by trans-esophageal electrical stimulation followed by CPR. The surviving rats were treated with FK866 (a selective inhibitor of NAMPT), Mdivi-1 (Drp1 inhibitor), FK866 + Mdivi-1, or vehicle and then underwent 24 h reperfusion. Hematoxylin and eosin staining and immunohistochemistry (to detect NSE) were used to evaluate brain injury. We performed immunofluorescent staining to analyze NLRP3 and GSDMD expression in microglia or astrocytes and western blot to determine expression of NLRP3, IL-1ß, GSDMD, Drp1, and Mfn2. Transmission electron microscopy was used to observe mitochondria. RESULTS: FK866 significantly decreased pathological damage to brain tissue, inhibited the activation of NLRP3 in microglia or astrocytes, downregulated the expression of NLRP3, IL-1ß, GSDMD, p-Drp1 protein, upregulated Mfn2 and improve mitochondrial morphology. CONCLUSIONS: Our results demonstrated that FK866 protects the brain against ischemia-reperfusion injury in rats after CA/CPR by inhibiting pyroptosis and inflammation mediated by Drp1.
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Acrilamidas/farmacologia , Anti-Inflamatórios/farmacologia , Encéfalo/efeitos dos fármacos , Reanimação Cardiopulmonar , Dinaminas/metabolismo , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Piperidinas/farmacologia , Piroptose/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Modelos Animais de Doenças , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Quinazolinonas/farmacologia , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de SinaisRESUMO
A La0.67Sr0.33MnO3 (LSMO) ferromagnetic layer and a Nd3+/Hf4+ co-substituted Bi4Ti3O12 (Bi3.15Nd0.85Ti3-xHfxO12 (BNTHx, x = 0, 0.025, 0.05, 0.1 and 0.15)) ferroelectric layer were successively deposited onto the (00 l)-oriented LaNiO3 (LNO) layer buffered (001) Si substrate via all chemical solution deposition (CSD) method. As a result, the BNTHx/LSMO ferromagnetic-ferroelectric composite films integrated on Si substrate exhibit high c-axis orientation. The Nd3+/Hf4+ co-substituted BNTHx films have the lower leakage current and the better ferroelectric properties than the mono-substituted Bi4Ti3O12 (Bi3.15Nd0.85Ti3O12 and Bi4Ti2.95Hf0.05O12) films. In particular, the BNTH0.05/LSMO/LNO film has the lowest leakage current density of 2.5 × 10-7 A/cm2 at 200 kV/cm, and the highest remnant polarization (Pr) of 27.3 µC/cm2. The BNTH0.05/LSMO/LNO composite film also exhibits the soft ferromagnetism characteristics with a high saturated magnetization of 258 emu/cm3 at 300 K, and the excellent magnetoelectric (ME) effect. The variations of ME voltage coefficient α E values with DC bias magnetic field H bias shows that the BNTH0.05/LSMO/LNO film has the high α E value at near zero H bias. Moreover, at H bias = 0 Oe, the α E value gradually increases from zero with the increasing of the AC magnetic field frequency, and eventually reaches about 18.9 V/cm·Oe at 100 kHz, suggesting the existence of self-biased ME effect.
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BaTi1-xSnxO3 (BTSn, 0 ≤ x ≤ 0.30) ceramics were prepared by both the conventional sintering (CS) and sparking plasma sintering (SPS). Composition, temperature and grain size dependences of the nonlinear dielectric behaviors were systematically studied. BTSn was found to have especially large tunability (≥90%), which is larger than most other Pb-free systems, and is comparable to Pb-based relaxors. The high dielectric tunability in BTSn is attributed to its specific domain structures. Besides, temperature dependent tunability of BTSn presents a dispersed behavior and the dispersion is enhanced with the increase of Sn4+ concentrations, which is explained by the compositional fluctuation model.
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Although the solution deposition of YBa2Cu3O7-x (YBCO) superconducting films is cost effective and capable of large-scale production, further improvements in their superconductivity are necessary. In this study, a deep UV (DUV) irradiation technique combined with a low-fluorine solution process was developed to prepare YBCO films. An acrylic acidic group as the chelating agent was used in the precursor solution. The acrylic acidic group was highly sensitive to DUV light at 254 nm and significantly absorbed UV light. The coated gel films exposed to DUV light decomposed at 150 °C and copper aggregation was prevented. The UV irradiation promoted the removal of the carbon residue and other by-products in the films, increased the density and enhanced the crystallinity and superconductivity of the YBCO films. Using a solution with F/Ba = 2, YBCO films with thicknesses of 260 nm and enhanced critical current densities of nearly 8 MA/cm2 were produced on the LaAlO3 (LAO) substrates.
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RuO2/TiQ2 coupled photocatalyst was prepared by sol-gel-dipping method. Being a model reaction, the photocatalytic degradation of direct fast black G was investigated in RuO2/TiO2 powder suspension irradiated by UV-lamp. The results showed that the addition of RuO2 to TiO2 greatly enhanced its photocatalytic activity, and the optimum dipped content of RuO2 was 0.16%, the optimum value of the calcinations temperature and the addition of RuO2/TiO2 powder were 500 degrees C and 5.00 g x L(-1), respectively. The photocatalytic degradation of direct fast black G was experimentally demonstrated to follow the Langmuir-Hinshelwood kinetic model, and the adsorption constant (14.22 L x mmol(-1)) and the reaction rate constant [4.94 x 10(-3) mmol(L x min)(-1)] were determined, respectively.
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Compostos de Rutênio/química , Titânio/química , Catálise/efeitos da radiação , Corantes/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Espectrofotometria , Espectrofotometria Ultravioleta , Fatores de Tempo , Raios Ultravioleta , Difração de Raios XRESUMO
OBJECTIVE: The mechanisms of mesenchymal stromal cells (MSCs)-mediated treatment of liver damage have been unclear. Two major mechanisms, which involve paracrine effects and/or direct trans-differentiation, have been proposed. To clarify which mechanism is more important, we planned to construct a recombinant plasmid expressing green fluorescent protein (GFP) driven by the cytomegalovirus (CMV) promoter and Pseudomonas aeruginosa exotoxin 40 (PE40) driven by the albumin (alb) promoter, which can induce cell death as soon as MSCs differentiate into hepatocytes. METHODS: To construct the recombinant eukaryotic expression vector pFlag-CMV-GFP-TM-albp-PE40, GFP, transmembrane domain of DLL1, alb promoter and PE40 were obtained by PCR and were inserted into pFlag-CMV-1. The expression of GFP was observed under a fluorescence microscope and the killing effect on hepatocytes was analyzed by flow cytometry. RESULTS: The recombinant plasmid inducing cell death in hepatocytes was successfully constructed, suggesting that the plasmid could be employed to study the mechanism of MSCs-mediated treatment on liver damage. CONCLUSION: This study might provide a promising tool for revealing the mechanism of MSCs-mediated treatment on liver diseases.