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1.
J Am Chem Soc ; 146(15): 10357-10366, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38574191

RESUMO

Electrochemical reduction of carbon dioxide to organic chemicals provides a value-added route for mitigating greenhouse gas emissions. We report a family of carbon-supported Sn electrocatalysts with the tin size varying from single atom, ultrasmall clusters to nanocrystallites. High single-product Faradaic efficiency (FE) and low onset potential of CO2 conversion to acetate (FE = 90% @ -0.6 V), ethanol (FE = 92% @ -0.4 V), and formate (FE = 91% @ -0.6 V) were achieved over the catalysts of different active site dimensions. The CO2 conversion mechanism behind these highly selective, size-modulated p-block element catalysts was elucidated by structural characterization and computational modeling, together with kinetic isotope effect investigation.

2.
Inorg Chem ; 63(39): 18484-18488, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39298650

RESUMO

Chalcophosphates are an important type of infrared nonlinear optical (NLO) candidates in view of their rich anionic motifs. Here, two copper chalcophosphates Cu3PSe4 (CPSe) and Cs2CuP3S9 (CCPS) were synthesized and studied as IR NLO materials. They both feature three-dimensional polyanionic frameworks constructed by similar T2-supertetrahedra, and the structure of CCPS can be derived from CPSe via introducing Cs and substituting Se with S. This structural evolution results in phase-matchable NLO behavior, enlarged optical band gap, and enhanced laser-induced damage threshold for CCPS. These results are elucidated by structure analysis and theoretical calculations, and the increased structural anisotropy contributes to the phase matchable behavior of CCPS. This work presents a case on how to adjust NLO properties via certain structure considerations, which may be extended to more systems for obtaining high-performance NLO materials.

3.
Inorg Chem ; 63(17): 7555-7559, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38624233

RESUMO

Noncentrosymmetric chalcogenides are promising candidates for infrared nonlinear-optical (NLO) crystals, and exploring high-performance ones is a hot topic and challengeable. Herein, the combination of AgQ4, InQ4, and SiQ4 (Q = S, Se) units with different S/Se ratios resulted in the discovery of the tetrahedral chalcogenides Ag2In2SiS4Se2 (1) and Ag2In2SiS5Se (2). They both crystallize in the monoclinic Cc space group with different local structures. Co-occupied S/Se sites only exist in 2, and the arrangement of [In2SiQ3] six-membered rings builds different helical chains and 3D [(In2SiQ6)2-]n polyanionic frameworks in 1 and 2. They show balanced NLO performances, including phase-matchable moderate NLO responses (0.7 and 0.5 × AGS) and enhanced laser-induced damage thresholds (4.5 and 5.1 × AGS). Theoretical calculations reveal that their NLO responses are predominantly contributed by the AgQ4 and InQ4 units.

4.
J Esthet Restor Dent ; 36(9): 1236-1248, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38563216

RESUMO

OBJECTIVE: Occlusal reconstruction is a critical intervention for patients with dental hard tissue defects, temporomandibular joint (TMJ) disorders, and jaw position abnormalities. Clinical efficiency and outcomes of these procedures have improved with advances in digital technologies. This case report aims to illustrate a comprehensive digital workflow for occlusal reconstruction in a patient with congenital dentition defects, emphasizing the application of digital technologies to enhance treatment outcomes. CLINICAL CONSIDERATIONS: A 28-year-old woman with previously installed porcelain-fused-to-metal bridge restorations presented with a fractured prosthesis and TMJ symptoms. A multidisciplinary approach was adopted involving the use of digital facebow, intraoral scanners, digital smile design, and CAD/CAM technologies. The process included the extraction of defective restorations, temporary restorations to refine jaw position, and final permanent restorations. The digital workflow facilitated precise diagnostics and treatment, culminating in the successful installation of permanent restorations. Regular follow-ups at one- and three-months post-treatment confirmed stable occlusal function and high patient satisfaction. CONCLUSIONS: This case report showcases the potential of multiple digital technologies to streamline complex dental treatments and achieve high-quality results. CLINICAL SIGNIFICANCE: The integration of digital technologies in occlusal reconstruction treatments offers significant benefits in terms of precision, patient comfort, and esthetic outcomes.


Assuntos
Fluxo de Trabalho , Humanos , Feminino , Adulto , Desenho Assistido por Computador
5.
Angew Chem Int Ed Engl ; 63(15): e202400760, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38348737

RESUMO

Achieving tunable emissions spanning the spectrum, from blue to near-infrared (NIR) light, within a single component is a formidable challenge with significant implication, particularly in tailoring multicolor luminescence for anti-counterfeiting purposes. In this study, we demonstrate a broad spectrum of emissions, covering blue to red and extending into NIR light in [BPy]2CdX4 : xSb3+ (BPy=Butylpyridinium; X=Cl, Br; x=0 to 0.08) through precise multisite structural fine-tuning. Notably, the multicolor emissions from [BPy]2CdBr4 : Sb3+ manifest a distinctive pattern, transitioning from blue to yellow in tandem with the host [BPy]2CdBr4 and further extending from yellow to NIR with its homologous [BPy]2CdCl4 : Sb3+, resulting in the simultaneous presence of intersecting and independent emission colors. Detailed modulation of chemical composition enables partial luminescence switching, facilitating the creation of diverse patterns with multicolor luminescence by employing [BPy]2CdX4 : xSb3+ as phosphors. This study for the first time successfully implements several groups of tunable emission colors in a single matrix via multisite fine-tuning. Such an effective strategy not only develops the specific relationships between tunable emissions and adjustable compositions, but also introduces a cost-effective and straightforward approach to achieving unique, high-level, plentiful-color and multiple-information-storage labels for advanced anti-counterfeiting applications.

6.
Cell Commun Signal ; 21(1): 7, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36635672

RESUMO

BACKGROUND: Skeletal muscle is comprised of heterogeneous myofibers that differ in their physiological and metabolic parameters. Of these, slow-twitch (type I; oxidative) myofibers have more myoglobin, more mitochondria, and higher activity of oxidative metabolic enzymes compared to fast-twitch (type II; glycolytic) myofibers. METHODS: In our previous study, we found a novel LncRNA-TBP (for "LncRNA directly binds TBP transcription factor") is specifically enriched in the soleus (which has a higher proportion of slow myofibers). The primary myoblast cells and animal model were used to assess the biological function of the LncRNA-TBP in vitro or in vivo. Meanwhile, we performed a RNA immunoprecipitation (RIP) and pull-down analysis to validate this interaction between LncRNA-TBP and TBP. RESULTS: Functional studies demonstrated that LncRNA-TBP inhibits myoblast proliferation but promotes myogenic differentiation in vitro. In vivo, LncRNA-TBP reduces fat deposition, activating slow-twitch muscle phenotype and inducing muscle hypertrophy. Mechanistically, LncRNA-TBP acts as a regulatory RNA that directly interacts with TBP protein to regulate the transcriptional activity of TBP-target genes (such as KLF4, GPI, TNNI2, and CDKN1A). CONCLUSION: Our findings present a novel model about the regulation of LncRNA-TBP, which can regulate the transcriptional activity of TBP-target genes by recruiting TBP protein, thus modulating myogenesis progression and inducing slow-twitch fibers. Video Abstract.


Assuntos
RNA Longo não Codificante , Animais , Proteína de Ligação a TATA-Box/genética , Proteína de Ligação a TATA-Box/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Músculo Esquelético/metabolismo , Regulação da Expressão Gênica , Desenvolvimento Muscular/genética
7.
Appl Opt ; 62(1): 153-161, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606860

RESUMO

We report a design method based on an annularly stitched aspherical surface for highly collimated optical systems with extended light sources. The annularly stitched aspherical surface is constructed as a circular central zone and one or more annular zones, which are rotationally symmetric and provide flexibility to satisfy the requirements of a practical design. An extended LED light source can be considered, and a backward ray-tracing process is used to construct the initial lens model. The specific optimization has been added step by step to modify the stitched surface to redistribute the light rays emitted from the extended source. The smoothness of the stitched surface is considered in the design and optimization process to guarantee the processability of the system. A prototype has been fabricated and tested, which demonstrates the validity of this method.

8.
J Cardiothorac Vasc Anesth ; 37(4): 539-546, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36717316

RESUMO

OBJECTIVES: To assess whether a preoperative bilateral thoracic paravertebral block (TPVB) would improve postoperative analgesia in infants and small children undergoing open cardiac surgery in the protocol of an ultra-fast track cardiac anesthesia (UFTCA). DESIGN: A single-center, prospective, randomized, controlled study. SETTING: At a tertiary children's medical center. PARTICIPANTS: A total of 180 children undergoing cardiac surgery, aged 1 month to 3 years. INTERVENTIONS: Patients are allocated randomly to TPVB and parent- and/or nurse-controlled intravenous analgesia (PNCA) group (Group T) or PNCA group (Group P). MEASUREMENTS AND MAIN RESULTS: The primary outcome is the postoperative pain scores. The secondary outcome are intraoperative consumption of sufentanil, time to extubation, using of neostigmine, cumulative total and invalid PCA attempts in 24 and 48 hours after surgery, hospitalization characteristics, perioperative blood glucose, postoperative arterial oxygen partial pressure, arterial carbon dioxide partial pressure (PaCO2) and brain natriuretic peptide (BNP). The postoperative pain scores within 24 hours, intraoperative consumption of sufentanil, total, and invalid PCA attempts in 24 and 48 hours, perioperative blood glucose and BNP on the seventh day in Group T were all significantly lower than those in Group P (p < 0.001). The time to extubation, the use of neostigmine, and PaCO2 on the sixth hour, postoperatively, were significantly smaller in Group T than those in Group P (p < 0.05). There were no significant differences in the hospitalizations between the 2 groups. CONCLUSIONS: A combination of bilateral single dose TPVB and PNCA pain management is superior to a PNCA pain management alone in infants and small children undergoing open cardiac surgery and contributes to a rapid recovery with preferable perioperative outcomes in the protocol of UFTCA.


Assuntos
Analgesia , Anestesia em Procedimentos Cardíacos , Humanos , Criança , Lactente , Sufentanil , Estudos Prospectivos , Glicemia , Neostigmina , Dor Pós-Operatória/tratamento farmacológico , Analgésicos Opioides
9.
Inorg Chem ; 61(11): 4752-4759, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35263085

RESUMO

Organic-inorganic hybrid metal halides (OIMHs) exhibiting white-light emission are a splendid class of emitters and are regarded as desired phosphors for solid-state lighting applications. Here we report a single-component white-light-emitting hybrid metal halide, namely, [C6H7ClN]CdCl3 (C6H7ClN = 4-(chloromethyl)pyridinium), which features a corrugated 1D anionic double chain composed of edge-shared CdCl6 octahedrons and exhibits broadband white-light emission with a photoluminescence quantum yield of 12.3% under 365 nm UV light irradiation. Density functional theory calculations and temperature-dependent emission spectral analysis unveil that the broadband emission of [C6H7ClN]CdCl3 is ascribed to self-trapped excitons. Moreover, a single-component white-light-emitting diode device with a correlated color temperature of 5214 K and color rendering index of 83.7 can be fabricated via coating [C6H7ClN]CdCl3 on a 365 nm UV light-emitting diode chip. Such a promising luminescent material provides guidance for the design and synthesis of OIMHs with unique structures and desired properties.

10.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 148-152, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495504

RESUMO

To analyze the changes and correlation of Mir-129 and Mir-29A-5p in vascular calcification in end-stage renal disease. A total of 97 patients with end-stage renal disease admitted to our hospital from August 2021 to August 2020 were selected as the research objects, and another 97 healthy people who underwent physical examination in our hospital during the same period were selected as the control study. According to X-ray examination, 97 subjects were divided into the vascular calcification group (39 cases) and the non-vascular calcification group (58 cases). Blood samples were extracted from each group, and the expressions of serum Mir-129 and Mir-29A-5p were detected by RT-PCR after centrifugation. The expressions of Mir-129 and Mir-29A-5p in healthy people with end-stage renal disease and vascular calcification were analyzed. To analyze the correlation of Mir-129 and Mir-29A-5p in vascular calcification of end-stage renal disease and its correlation with vascular calcification of end-stage renal disease. Compared with healthy people, the expression of Mir-129 and Mir-29A-5p in patients with the end-stage renal disease was abnormally increased, and there was a difference between the two groups (P<0.05). The expression levels of Mir-129 and Mir-29A-5p in patients with end-stage renal disease without vascular calcification were lower than those in the vascular calcification group, and there were differences between the two groups (P<0.05). Compared with mild vascular calcification, mir-129 and Mir-29A-5p expressions were higher in moderate and severe vascular calcification patients. In addition, compared with moderate patients, the expressions of Mir-129 and Mir-29a-5p were lower in mild patients and higher in severe patients. The expressions of Mir-129 and Mir-29A-5p in patients with mild and moderate vascular calcification were lower than those in patients with severe vascular calcification, and there were differences among the three groups (P < 0.05). Mir-129 and Mir-29A-5p were positively correlated with vascular calcification in end-stage renal disease (R =5.426, P=0.001). Mir-129 was positively correlated with vascular calcification in end-stage renal disease (r=0.649, P=0.001). Mir-29a-5p was positively correlated with vascular calcification in end-stage renal disease (r=0.529, P=0.001). Mir-129 and Mir-29a-5p showed high expression in the patients with end-stage renal disease, and they also increased with the occurrence of vascular calcification, and they showed a positive correlation in the vascular calcification of end-stage renal disease.


Assuntos
Falência Renal Crônica , MicroRNAs , Humanos , MicroRNAs/metabolismo , Falência Renal Crônica/complicações , Falência Renal Crônica/genética
11.
Cell Mol Biol (Noisy-le-grand) ; 68(7): 70-74, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36495516

RESUMO

The objective of the current study was to analyze the expression of mir-29a-5p, osteosclerotin and fetuin-A in patients with chronic kidney disease and their correlation with vascular calcification. For this purpose, 162 patients with chronic kidney disease treated in our hospital from January 2020 to January 2022 were selected retrospectively, and then 162 healthy people who underwent physical examination with our hospital in the same period were selected. The expressions of serum mir-29a-5p, sclerostin and fetuin-A were analyzed after fasting venous blood was drawn from the two groups. According to the coronary artery calcification score (CACS), patients with chronic kidney disease were divided into the calcification group (69 cases) and the non-calcification group (93 cases). The expressions of mir-29a-5p, sclerostin and fetuin-A in the two groups were analyzed, and the correlation between the three in chronic kidney disease and vascular calcification was analyzed. Results showed that compared with the control group, the expression of mir-29a-5p and sclerostin in the study group was higher, and the expression of fetuin-A was lower, the difference was statistically significant (P < 0.05); The expression of mir-29a-5p, sclerostin and fetuin-A in calcified group was higher than that in non-calcified group, and the expression of fetuin-A was lower (P < 0.05); Mir-29a-5p and sclerostin showed positive correlation (r=6.776, P=0.011); The expression of mir-29a-5p and fetuin-A showed negative correlation (r=-5.326, P=0.001); The expression of mir-29a-5p and sclerostin showed negative correlation (r=-9.677, P=0.001); Mir-29a-5p and sclerostin were positively correlated with vascular calcification (r=0.695, P=0.001; r=0.715, P=0.001), and fetuin-A was positively correlated with vascular calcification (r = -0.953, P = 0.001). Then, Mir-29a-5p, sclerostin and fetuin-A are abnormally expressed in chronic kidney disease. There is an abnormal correlation among them in chronic kidney disease, and they are correlated with vascular calcification.


Assuntos
Doença da Artéria Coronariana , MicroRNAs , Insuficiência Renal Crônica , Calcificação Vascular , Humanos , Fetuínas , Estudos Retrospectivos , Calcificação Vascular/genética , Insuficiência Renal Crônica/genética , alfa-Fetoproteínas , MicroRNAs/genética
12.
Int Endod J ; 55(10): 1091-1102, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35833329

RESUMO

AIM: The use of high-concentration sodium hypochlorite (NaOCl) as an endodontic irrigant remains controversial because of its potential impact on the fracture strength of endodontically treated teeth. This study evaluated the effects of using different NaOCl concentrations, with 2-min-ethylenediaminetetraacetic acid (EDTA) as the final active irrigant, on the biomechanical and structural properties of root dentine. METHODOLOGY: A new test method, which is more clinically relevant, was utilized to calculate the fracture strength of root dentine. Bovine incisors were used to obtain root dentine discs. The root canals were enlarged to mean diameter of 2.90 mm with a taper of 0.06. The resulting discs were divided into five groups (n = 20) and treated with different concentrations of NaOCl (5.25%, 2.5%, and 1.3%) for 30 min plus 17% EDTA for 2 min. The discs were then loaded to fracture by a steel rod with the same taper through the central hole. The fractured specimens were examined by scanning electron microscopy to evaluate changes in the dimensions of the remaining intertubular dentine and the tubular radius. Micro-hardness was also measured with a Knoop diamond indenter along a radius to determine the depth of dentine eroded by the irrigation. Results were analysed by one-way anova and the Tukey test. The level of significance was set at α = 0.05. RESULTS: The damage by NaOCl increased with its concentration. 5.25% NaOCl greatly reduced the fracture strength of root dentine from 172.10 ± 30.13 MPa to 114.58 ± 26.74 MPa. The corresponding reduction in micro-hardness at the root canal wall was 34.1%. The damages reached a depth of up to 400 µm (p < .05). Structural changes involved the degradation of the intratubular wall leading to enlarged dentinal tubules and the loss of intertubular dentine. Changes in the microstructural parameters showed positive linear relationships with the fracture strength. CONCLUSIONS: With the adjunctive use of EDTA, NaOCl caused destruction to the intratubular surface near the root canal and, consequently, reduced the root dentine's mechanical strength. The higher the concentration of NaOCl, the greater the effect. Therefore, endodontists should avoid using overly high concentration of NaOCl for irrigation to prevent potential root fracture in endodontically treated teeth.


Assuntos
Hipoclorito de Sódio , Dente não Vital , Animais , Bovinos , Cavidade Pulpar , Dentina , Ácido Edético/farmacologia , Humanos , Irrigantes do Canal Radicular/farmacologia , Preparo de Canal Radicular , Hipoclorito de Sódio/farmacologia
13.
Int J Mol Sci ; 23(12)2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35743265

RESUMO

The immune cell inflammation response is closely related to the occurrence of disease, and much evidence has shown that circular RNAs (circRNAs) play vital roles in the occurrence of disease. However, the biological function and regulatory mechanisms of circRNAs in the immune cell inflammation response remain poorly understood. In this study, we constructed an inflammatory model using lipopolysaccharide (LPS)-stimulated chicken macrophage lines (also known as HD11) to verify the function and mechanism of the novel circDCLRE1C (ID: gga_circ_0001674), which was significantly upregulated in spleen tissues infected by coccidia and the macrophage cells exposed to LPS. The results showed that circDCLRE1C aggravated LPS-induced inflammation and apoptosis in HD11 cells. Systemically, circDCLRE1C acted as a sponge for miR-214b-3p binding sites thereby regulating the expression of STAT3. The overexpression of miR-214b-3p rescued the pro-inflammatory effect of circDCLRE1C in HD11 cells stimulated with LPS, and rescued the high expression of STAT3. In conclusion, our study showed that circDCLRE1C could aggravate LPS-induced inflammation and apoptosis through competitive adsorption of miR-214b-3p, thereby increasing the expression of STAT3.


Assuntos
Lipopolissacarídeos , MicroRNAs , Apoptose/genética , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Lipopolissacarídeos/toxicidade , Macrófagos , MicroRNAs/genética , RNA Circular/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais
14.
Eur J Neurosci ; 54(10): 7409-7421, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34618385

RESUMO

The activation of spinal astrocytes and release of neuroinflammatory mediators are important events in neuropathic pain (NP) pathogenesis. In this study, we investigated the role of Wnt10a/ß-catenin signalling in kindlin-1-mediated astrocyte activation using a chronic constriction injury (CCI) NP rat model. Using kindlin-1 overexpression and knockdown plasmids, we assessed hyperalgesia, changes in spinal astrocyte activation and the release of inflammatory mediators in a NP rat model. We also performed coimmunoprecipitation, Western blotting and real-time polymerase chain reaction (PCR) to characterize the underlying mechanisms of kindlin-1 in astrocyte cultures in vitro. Kindlin-1 was significantly upregulated in CCI rats and promoted hyperalgesia. Moreover, we observed increased kindlin-1, Wnt10a and glial fibrillary acidic protein (GFAP; biomarker for astroglial injury) levels and the release of inflammatory mediators in NP rats (p < 0.05). Inhibiting GFAP in vitro led to decreased kindlin-1 levels, prevented astrocyte activation, decreased Wnt10a level and the release of inflammatory mediators (p < 0.05). Coimmunoprecipitation showed that kindlin-1 can interact with Wnt10a. We showed that kindlin-1-mediated astrocyte activation was associated with Wnt10a/ß-catenin signalling and the downstream release of inflammatory mediators in a CCI NP rat model. Our findings provide novel insights into the molecular mechanisms of kindlin-1-mediated astrocyte activation after CCI.


Assuntos
Astrócitos , Neuralgia , Animais , Hiperalgesia , Ratos , Ratos Sprague-Dawley , Proteínas Wnt , beta Catenina
15.
Int J Urol ; 28(11): 1157-1163, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34378238

RESUMO

OBJECTIVE: Henoch-Schönlein purpura nephritis has become a significant threat to children's health. Traditional combined therapy of glucocorticoids and cyclophosphamide leads to severe toxicity and complications. Therefore, identifying a feasible and effective strategy with low side-effects for the treatment of Henoch-Schönlein purpura nephritis is of great significance. METHODS: A randomized, controlled trial was carried out. A total of 279 children with Henoch-Schönlein purpura nephritis were recruited and randomly divided into three groups: control group (receiving the current standard therapy), TA group (receiving tacrolimus) and TA + tripterygium glycosides group (receiving tacrolimus + tripterygium treatment). The total duration of the trial was 6 months, and the duration of follow-up observation was 9 months. RESULTS: Various therapies showed similar therapeutic effects in the third and sixth months. The relief of Henoch-Schönlein purpura nephritis symptoms caused by TA + tripterygium glycosides was slower than the TA and control groups. The incidence of adverse reactions in the TA + tripterygium glycosides group was lower in the control and TA groups. The final treatment effect of the experimental groups was better than the control group. The recurrence rate in the TA + tripterygium glycosides group was also significantly lower. CONCLUSION: Tacrolimus and tripterygium glycosides combined therapy had better effects and safety for long-term treatment of Henoch-Schönlein purpura nephritis.


Assuntos
Vasculite por IgA , Nefrite , Criança , Glicosídeos/efeitos adversos , Humanos , Vasculite por IgA/complicações , Vasculite por IgA/tratamento farmacológico , Nefrite/tratamento farmacológico , Nefrite/etiologia , Tacrolimo/efeitos adversos , Tripterygium
16.
J Am Chem Soc ; 142(29): 12613-12619, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32090553

RESUMO

The low-cost hydrogen production from water electrolysis is crucial to the deployment of sustainable hydrogen economy but is currently constrained by the lack of active and robust electrocatalysts from earth-abundant materials. We describe here an unconventional heterostructure composed of strongly coupled Ni-deficient LixNiO nanoclusters and polycrystalline Ni nanocrystals and its exceptional activities toward the hydrogen evolution reaction (HER) in aqueous electrolytes. The presence of lattice oxygen species with strong Brønsted basicity is a significant feature in such heterostructure, which spontaneously split water molecules for accelerated Volmer H-OH dissociation in neutral and alkaline HER. In combination with the intimate LixNiO and Ni interfacial junctions that generate localized hotspots for promoted hydride coupling and hydrogen desorption, the catalysts produce hydrogen at a current density of 10 mA cm-2 under overpotentials of only 20, 50, and 36 mV in acidic, neutral, and alkaline electrolytes, respectively, making them among the most active Pt-free catalysts developed thus far. In addition, such heterostructures also exhibited superior activity toward the hydrogen oxidation reaction in alkaline electrolytes.

17.
Appl Opt ; 59(28): 8724-8732, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104555

RESUMO

Electrical lighting design is usually based on the illumination design. Its main task is to ensure that the electricity and optical system can be normal, safe, reliable, and economically viable. In this paper, we propose a design and optimization method for outdoor illumination systems to generate relatively powerful light beams for far distances. The illumination systems are based on highly integrated LED modules instead of high intensity discharge lamps. The size of the LED light-emitting surface is 2.5mm×2.1mm, and the secondary optical elements are composed of a basic plano-convex lens and a Fresnel lens. The results of simulation demonstrate that the emission angle of the system is 1.1°, and the central illumination at 2500 m away is more than 1 lx. The total system is simple but practical, and several groups can be combined into a larger system. Two proof-of-concept prototypes producing acceptable illuminance are developed, and one is composed of four groups whose light is visible from 5000 m away. Both are fully waterproof and in a high degree of protection. The systems can provide up to 12 h of continuous lighting, and the operating temperature rise is less than 25°C. The results indicate that our design can be applicable for practical wild working sites.

18.
J Mater Sci Mater Electron ; 31(16): 13688-13695, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38624446

RESUMO

Tantalate is considered as a valuable and efficient luminescence host because of its intense absorption in the ultraviolet area and excellent chemical properties. In this work, a series of pure YTaO4:Eu3+ and/or Tb3+ crystals were prepared via a sol-gel combustion method. The morphology, structure, and optical properties of the samples were discussed in detail. The Eu3+, Tb3+ co-doped YTaO4 samples are consisted of small spherical particles of around 18 nm. The prepared YTaO4:Tb3+ and/or Eu3+ samples exhibit the characteristic wide excitation band around 210-300 nm, the characteristic narrow red emission of Eu3+ (5D0 → 7F2) transitions and green emission of the Tb3+ (5D4 → 7F5) transitions when excited by UV light. It is focused on the energy transfer processes from the YTaO4 to Tb3+ as well as Eu3+ ions and from Tb3+ to Eu3+ ions of YTaO4:Eu3+/Tb3+ phosphors. Color-tunable emissions are realized through adjusting the types of rare earth ion (Eu3+ and Tb3+) and relative doping concentrations excited by a single wavelength. That is to say, the obtained Tb3+ and Eu3+ co-doped YTaO4 phosphors have a promising prospect in lasers, white light diodes (WLED), fluorescent lamp, and field emission display devices, etc.

19.
Soft Matter ; 15(43): 8827-8839, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31603449

RESUMO

Determining the nature of the microscopic mechanism of tribological properties by experimental methods for a polymer material surface/interface in the sliding friction process is a challenge. Molecular dynamics simulations were conducted by sliding a rigid indenter over the amorphous polyethylene. The results show that the friction is mainly composed of plough force and adhesion force. The average friction of adhesive contact is greater than that of frictionless contact because of the adhesion effect. The difference of average friction between adhesive contact and frictionless contact increases with increasing indentation depth because of the plough force effect. The elastic deformation of amorphous polyethylene in the cohesive zone is related to van der Waals interaction energy, whereas the plastic deformation was mainly dominated by bond angle energy and dihedral energy of the molecular chain for amorphous polyethylene. Molecular chains of amorphous polyethylene extend along the sliding direction and agglomerate along the indentation direction. The flexibility of the molecular chains increases with the increase of temperature and facilitates the molecular chains returning more easily to their original state.

20.
Cell Physiol Biochem ; 46(5): 1768-1778, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29705805

RESUMO

BACKGROUND/AIMS: Earlobe color is a typical external trait in chicken. There are some previous studies showing that the chicken white/red earlobe color is a polygenic and sex-linked trait in some breeds, but its molecular genetic and histological mechanisms still remain unclear. METHODS: We herein utilized histological section, genome-wide association study (GWAS) and RNA-seq, further to investigate the potential histological and molecular genetic mechanisms of white/red earlobe formation in Qiangyuan Partridge chicken (QYP). RESULTS: through histological section analysis, we found the dermal papillary layer of red earlobes had many more blood vessels than that of white earlobes. And we identified a total of 44 SNPs from Chromosome 1, 2, 3, 4, 9, 10, 11, 13, 19, 20, 23 and Z, that was significantly associated with the chicken white/red earlobe color from GWAS, along with 73 significantly associated genes obtained (e.g., PIK3CB, B4GALT1 and TP63), supporting the fact that the white/red earlobe color was also polygenic and sex-linked in QYP. Importantly, PIK3CB and B4GALT1 are both involved in the biological process of angiogenesis, which may directly give rise to the chicken white earlobe formation through regulating blood vessel density in chicken earlobe. Additionally, through contrast of RNA-seq profiles between white earlobe skins and red earlobe skins, we further identified TP63 and CDH1 differentially expressed. Combined with the existing knowledge of TP63 in epithelial development and tumor angiogenesis, we propose that down-regulated TP63 in white earlobes may play roles in thickening the skin and decreasing the vessel numbers in dermal papillary layer, thereby contributing to the white earlobe formation via paling the redness of the skin in QYP, but the specific mechanism remains to be further clarified. CONCLUSION: our findings advance the existing understanding of the white earlobe formation, as well as provide new clues to understand the molecular mechanism of chicken white/red earlobe color formation.


Assuntos
Galinhas/genética , Animais , Galinhas/anatomia & histologia , Galinhas/fisiologia , Orelha/anatomia & histologia , Orelha/fisiologia , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Masculino , Pigmentação
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