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1.
Adv Mater ; : e2405186, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39410718

RESUMO

Plasmonic nanogaps in strongly coupled metal nanostructures can confine light to nanoscale regions, leading to huge electric field enhancement. This unique capability makes plasmonic nanogaps powerful platforms for boosting light-matter interactions, thereby enabling the rapid development of novel phenomena and applications. This review traces the progress of nanogap systems characterized by well-defined morphologies, controllable optical responses, and a focus on achieving extreme performance. The properties of plasmonic gap modes in far-field resonance and near-field enhancement are explored and a detailed comparative analysis of nanogap fabrication techniques down to sub-nanometer scales is provided, including bottom-up, top-down, and their combined approaches. Additionally, recent advancements and applications across various frontier research areas are highlighted, including surface-enhanced spectroscopy, plasmon-exciton strong coupling, nonlinear optics, optoelectronic devices, and other applications beyond photonics. Finally, the challenges and promising emerging directions in the field are discussed, such as light-driven atomic effects, molecular optomechanics, and alternative new materials.

2.
Int J Clin Pharmacol Ther ; 62(10): 460-478, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39120081

RESUMO

Pulmonary fibrosis (PF) is a chronic and progressive pulmonary interstitial disease of unknown etiology and is also a sequela in severe patients with the Coronavirus Disease 2019 (COVID-19). Seven databases were systematically searched to evaluate the preclinical evidence of Tanshinone IIA (Tan IIA) on PF. The quality of the included studies was assessed using a 10-item risk of bias tool, and data were analyzed using RevMan 5.3 software. 22 experiments from 12 studies on a total of 248 animals were included. The results showed that PF phenotype, such as fibrotic score, collagen I (Col-I), collagen III (Col-III), hydroxyproline (Hyp), in the group treated with Tan IIA were significantly lower than those in the model group (p < 0.00001). The potential mechanisms of Tan IIA improvement of PF involve reducing inflammation, antioxidation, and suppressing activation of transforming growth factor beta 1 (TGF-ß1). The subgroup analysis of different models, different rat species, and different dosage time showed significant reduction in fibrotic scores and Hyp levels with Tan IIA. The preclinical evidence indicated that Tan IIA might be a potent and promising agent for PF, but this conclusion should be further confirmed with more research.


Assuntos
Modelos Animais de Doenças , Fenantrenos , Fibrose Pulmonar , Animais , Humanos , Ratos , Abietanos/farmacologia , Abietanos/uso terapêutico , COVID-19/complicações , Diterpenos/farmacologia , Diterpenos/administração & dosagem , Diterpenos/uso terapêutico , Fenantrenos/administração & dosagem , Fenantrenos/farmacologia , Fenantrenos/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia
3.
RSC Adv ; 14(27): 19054-19061, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38873555

RESUMO

A dual-bed catalyst was prepared for the conversion of C8 aromatics. The upper bed layer consisted of ZSM-5 covered with SiO2, primarily utilized for ethylbenzene dealkylation. By employing tetraethyl orthosilicate (TEOS) as a deposition agent through the chemical liquid deposition (CLD) method, the modified ZSM-5 catalyst exhibited optimal catalytic performance at a TEOS addition of 0.6 g per gram of catalyst. The lower bed layer contained ZSM-39 catalyst, mainly employed for xylene isomerization reaction. ZSM-39 was synthesized using pyrrolidine as the template, and the best catalytic performance was achieved when the OH-/SiO2 molar ratio in the synthesis system was 0.05. The mass ratio between the upper and lower agents was maintained at 1 : 1. Compared to traditional single-bed ZSM-5 catalysts, the dual-bed catalyst demonstrated enhanced activity and selectivity.

4.
RSC Adv ; 14(27): 19264-19270, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38887638

RESUMO

The isomerization process of xylene in the liquid phase has garnered significant attention due to its low energy consumption and high selectivity. However, conventional ZSM-5 zeolites have exhibited significantly diminished activity in this process, primarily attributed to diffusion barriers. To address this issue, Nano-ZSM-5 zeolite was synthesized using tetrapropylammonium hydroxide (TPAOH) as a structure direct agent (SDA) and introducing silicate-1 (S-1) as a crystallization seed. The impact of OH-/SiO2 molar ratio on the sample morphology was investigated. The structure of Nano-ZSM-5 zeolite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 physical -sorption analysis. The results demonstrate that the addition of S-1 crystal seeds enables the formation of ZSM-5 crystallites with diminutive particle sizes (∼20 nm). Furthermore, variations in the OH-/SiO2 molar ratio within the synthetic system impact crystallite aggregation, excessively high or low ratios result in severe aggregation, leading to decreased specific surface area and mesoporous volume. By optimizing the OH-/SiO2 molar ratio to 0.2, the sample exhibits exceptional dispersibility with a specific surface area of 420 m2 g-1 and a mesoporous volume extending to 0.57 cm3 g-1. When utilized as a catalyst for liquid-phase xylene isomerization, nano-ZSM-5 demonstrates superior catalytic performance compared to traditional zeolite.

5.
RSC Adv ; 14(7): 4804-4809, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38323018

RESUMO

Herein, we describe rhodium-catalysed C-H bond activation for [3 + 2] annulation using hydrazide and vinylene carbonate, providing an efficient method for synthesising unsubstituted 1-aminoindole compounds. Characterised by high yields, mild reaction conditions, and no need for external oxidants, this transformation demonstrates excellent regioselectivity and a wide tolerance for various functional groups.

6.
Int J Biol Macromol ; 253(Pt 6): 126367, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37591433

RESUMO

The development of membranes for protein purification has stringent requirement of disinfection resistance, low protein adsorption and anti-fouling, without changing protein structure. In this study, hydrophilic titanium dioxide (TiO2)/calcium alginate (TiO2/CaAlg) hydrogel membranes were prepared by a simple ionic cross-linking method. The effects of the porogenic agent polyethylene glycol (PEG) concentration, the molecular weight of PEG, and the concentration of TiO2 on the filtration properties were systematically investigated. The TiO2/CaAlg membrane exhibited excellent bovine serum albumin (BSA) rejection and anti-fouling properties. The mechanical properties and surface energy of the TiO2/CaAlg membrane were significantly improved. The chemical bonding mechanism of TiO2 and NaAlg was investigated by molecular dynamic simulation. The TiO2/CaAlg membrane had good chlorine resistance and could be disinfected or cleaned with sodium hypochlorite. The TiO2/CaAlg hydrogel membrane loaded with polyhydroxybutyrate (PHB) nanofibers maintained high flux (136.7 L/m2h) and high BSA rejection (98.0 %) at 0.1 MPa. The results of circular dichroism and synchronous fluorescence indicated that the secondary structure of BSA was maintained after membrane separation. This study provides one method for the preparation of green and environmentally friendly membrane for protein purification.


Assuntos
Alginatos , Cloro , Alginatos/química , Hidrogéis , Filtração , Soroalbumina Bovina , Polietilenoglicóis , Membranas Artificiais
7.
Opt Express ; 30(21): 37753-37759, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258357

RESUMO

Plasmonic demultiplexers hold promise for the realization of the subwavelength and high-splitting ratio dichroic splitter and have a wide range of applications from optical communication, and manipulation to ultrafast data treatment. However, this vision has not been realized for a long time due to lacking the suitable splitting structure design, which limits its further development of integrated photonic circuits. Here, we demonstrate a plasmonic demultiplexer with subwavelength feature size (0.54 µm) and broadband spectral (620-870 nm) range, and high-splitting ratio (17 dB in experiments and 20 dB in calculations). It consists of two adjacent Fabry-Perot cavities (covered by PMMA polymer) and coupling gratings, which are integrated with the Au waveguide. The relatively simple double cavities design of our device has a simple theoretical analysis and fabrication process. Our work has relevance for various optical applications, such as multiple wavelength photodetectors and optical multichannel interconnects.

8.
Medicina (Kaunas) ; 58(10)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36295577

RESUMO

Background and objectives: Objective, accurate, and intuitive evaluation of knee joint function in patients with knee osteoarthritis (KOA) is important. This study aimed to clarify the gait characteristics of patients with bilateral KOA and their correlation with Western Ontario and McMaster University Osteoarthritis Index (WOMAC). Materials and Methods: 20 patients with bilateral KOA and 20 conditionally matched healthy individuals were enrolled in the experimental and control groups, respectively. Footscan and CODA motion gait analysis systems were used to analyse the gait parameters. Gait spatiotemporal parameters and knee joint motion parameters were collected. Weight-bearing balance and walking stability were assessed using discrete trends of relevant gait indicators. Patients in the experimental group were evaluated using WOMAC. Pearson's correlation analysis was performed on the gait data and WOMAC score data of the experimental group. Results: Velocity, cadence, step length, and stride length of the experimental group were significantly lower than those of the control group (p < 0.01). Step time and gait cycle were significantly greater in the experimental group than in the control group (p < 0.01). Total stance and double-stance times of the experimental group were significantly greater than those of the control group (p < 0.01), whereas the single-stance time was shorter than that of the control group (p < 0.01). The range of motion and maximum flexion angle in the experimental group were significantly lower than those in the control group (p < 0.01), and the minimum angle of knee extension was greater than that in the control group (p < 0.01). The discrete trend of weight-bearing balance and walking stability gait index in the experimental group was greater than that in the control group. The WOMAC score and gait analysis were significantly correlated (p < 0.05). Conclusions: The gait function of patients with KOA is significantly worse than that of normal people. The WOMAC scale and gait analysis can be used to assess KOA severity from different perspectives with good consistency.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/diagnóstico , Análise da Marcha , Universidades , Ontário , Marcha , Articulação do Joelho
9.
Orthop Traumatol Surg Res ; 108(5): 103295, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35552043

RESUMO

INTRODUCTION: The application of antibiotics loaded bone cement (ALBC) in the revision of failed total knee arthroplasty (TKA) has been widely accepted to reduce risk of peri-prosthetic infection. However, the prophylactic use of ALBC in primary TKA remains controversial. This study was aimed to identify the prophylactic effect on peri-prosthetic infection and safety of ALBC in primary TKA. HYPOTHESIS: The application of ALBC could reduce the risk of peri-prosthetic infection in primary TKA. MATERIALS AND METHODS: Electronic platforms including PubMed, EMBASE, and CENTRAL were retrieved to identify studies comparing outcomes of prophylactic ALBC and plain cement in primary TKA. For outcomes reported as dichotomous variable and continuous variable, risk ratio (RR) and weighted mean difference (WMD) as well as their 95% confidence intervals (95% CI) were selected as the effect sizes for pooling. While for those outcomes reported the adjusted effect sizes such as odds ratio (OR, derived from multivariate logistic regression), and hazard ratio (HR, derived from multivariate COX proportional hazard model), the reported effect sizes were selected for pooling. RESULTS: A total of 17 studies with 2,074,844 patients (1,093,920 in ALBC group and 980,924 in plain cement group) were eligible for final inclusion. No significant difference was found between ALBC and plain cement groups both for the unadjusted (RR=1.02, 95% CI: 0.86∼1.21, p=0.832) and adjusted (OR=0.94, 95% CI: 0.76∼1.17, p=0.596) peri-prosthetic infection rate. ALBC application was related to significantly increased length of hospital stay (WMD=0.13, 95% CI: 0.10∼0.17, p<0.001). There was no significance on the difference of operation related adverse events between two groups (RR=1.31, 95% CI: 0.68∼2.52, p=0.420). Significantly increased risks of acute renal failure and readmission, and temporarily increased ototoxicity in ALBC group were reported in one of the primary study. DISCUSSION: There is no sufficient evidence supporting decreased peri-prosthetic infection rate with ALBC application in primary TKA. What's more, it must be taken into consideration about the safety and added cost of additional impregnated antibiotics. LEVEL OF EVIDENCE: III; meta-analysis.


Assuntos
Artroplastia do Joelho , Infecções Relacionadas à Prótese , Antibacterianos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Cimentos Ósseos/uso terapêutico , Humanos , Tempo de Internação , Infecções Relacionadas à Prótese/tratamento farmacológico
10.
J Orthop Surg Res ; 17(1): 152, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264236

RESUMO

BACKGROUND: To compare the gait patterns between posterior cruciate retention and substitution in total knee arthroplasty (TKA). METHODS: Electronic databases including the PubMed, Embase, CINAHL, Web of Science, and Cochrane databases were searched to identify clinical trials investigating posterior cruciate retention versus substitution in TKA. The outcome measurements were the kinematic gait parameters (flexion at heel strike, maximum flexion during loading response, flexion range during loading, minimal flexion at terminal stance, maximal flexion at the swing, and total flexion during the gait cycle), Knee Society Score (KSS), knee flexion, knee extension, and walking speed. Statistical software Review Manager 5.4 and Stata 14.0 were used for data analysis. RESULTS: There were finally 9 studies included in this meta-analysis. The results did not reveal differences between posterior cruciate retention (CR) and posterior cruciate substitution (PS) groups in TKA, in terms of kinematic gait parameters, knee extension, walking speed, and KSS. However, the PS group had a significantly larger knee flexion angle than that in the CR group [weighted mean difference = - 3.20, 95% CI - 6.13 to - 0.28, P = 0.03]. CONCLUSION: Both the posterior cruciate retention and posterior cruciate substitution lead to obvious improvements in patient function and have their advantages in getting a good cup position. The PS design is significantly better on the knee flexion, while there are no statistical differences in kinematic gait parameters and outcome scores between them. This might indicate that surgeons do not necessarily need a PS design to substitute the posterior cruciate ligament during TKA.


Assuntos
Artroplastia do Joelho/métodos , Marcha/fisiologia , Osteoartrite do Joelho/cirurgia , Reconstrução do Ligamento Cruzado Posterior/métodos , Ligamento Cruzado Posterior , Fenômenos Biomecânicos , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Prótese do Joelho , Amplitude de Movimento Articular/fisiologia
11.
Nano Lett ; 22(2): 688-694, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35025516

RESUMO

On-chip nanoscale optical platforms capable of efficient second harmonic generation (SHG) are highly desired for optical sensing, subwavelength coherent sources, and quantum photonic devices. Here, we develop a remotely excited dual cavity resonance scheme to achieve significantly enhanced SHG in a CdSe nanobelt on Au film hybrid waveguide system. The SHG emission with superior efficiency originates from counter-propagating plasmonic modes interference in a horizontal Fabry-Pérot (FP) cavity enabled by remote excitation of propagating surface plasmons, which is further enhanced through a vertical FP cavity. With this effective cooperation of hybrid plasmon modes and FP cavity modes, 2 orders of magnitude enhancement of the conversion efficiency (3.5 × 10-4 W-1) is achieved compared to the off-resonance case. Our design provides new insight into the development of a multifunctional hybrid plasmonic device toward on-chip nonlinear nanophotonic applications.

12.
Medicine (Baltimore) ; 100(28): e26632, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34260555

RESUMO

ABSTRACT: BCL7B plays a potential role in the progression of various cancers, while its role in sarcomas is unknown. We aimed to evaluate BCL7B's diagnostic and prognostic value, and potential BCL7B-related mechanisms in sarcomas based on The Cancer Genome Atlas (TCGA) database. We collected patients with sarcoma from TCGA. Wilcoxon rank sum test was used to compare the expression of BCL7B in sarcoma samples with different clinical-pathologic features. Univariate Cox regression analysis and multivariate Cox regression analysis were used to evaluate prognosis factors for sarcoma. Gene set enrichment analysis (GSEA) was conducted to elucidate the significant functions and pathways associated with BCL7B. BCL7B was a potential biomarker for distinguishing normal and tumor tissues with the analysis of ROC curve (AUC = 0.588). Low BCL7B expression was significantly correlated with tumor multifocal (OR = 0.39 for yes vs no), larger residual tumor (OR = 0.40 for R1,R2 vs RO), male gender (OR = 0.48 for male vs female) and White race (OR = 0.29 for White vs Asian, Black or African American). High BCL7B expression was correlated with leiomyosarcoma histological type (OR = 6.08 for leiomyosarcoma vs dedifferentiated liposarcoma, pleomorphic sarcoma). Univariate and multivariate Cox regression analysis showed that low BCL7B expression was independently associated with poor overall survival (P = .008). GSEA showed that GPCR (G protein-coupled receptors) ligand binding, secreted factors, class A1 rhodopsin-like receptors, extracellular matrix organization, core matrisome, Fc epsilon receptor I mediated NF-κB activation, and WNT signaling pathway were differentially enriched in BCL7B low expression phenotype (|NES| > 1, adjusted P value <.05, and FDR value <0.25). BCL7B may play an important role in sarcoma progression and may be a potential biomarker for prognosis and diagnosis in sarcomas.


Assuntos
Proteínas/genética , Sarcoma/genética , Sarcoma/patologia , Idoso , Biomarcadores Tumorais , Biologia Computacional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Grupos Raciais , Análise de Regressão , Sarcoma/diagnóstico , Fatores Sexuais
13.
Org Biomol Chem ; 19(7): 1498-1502, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33529298

RESUMO

C-H activation of sulfoxonium ylides catalyzed by rhodium(iii) with subsequent annulation by alkynylsulfones was accomplished. This methodology offers a step-economical approach for assembling C3-sulfone-substituted naphthols with a high level of regioselectivity that is complementary to previous protocols. The approach has an extensive substrate spectrum and broad functional group tolerance.

14.
RSC Adv ; 11(18): 10935-10940, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35423577

RESUMO

Efficient strategies for producing bio-based reagents from sustainable biomass are highly attractive for cost-effective sustainable manufacturing. In this study, a series of eco-friendly Zr-based catalysts (basic zirconium carbonate, zirconium dioxide and zirconium hydroxide) were investigated for the efficient conversion of dihydroxyacetone to ethyl lactate in a one-pot system, in which basic zirconium carbonate exhibited the best performance with 100% dihydroxyacetone conversion and 85.3% EL (ethyl lactate) yield at 140 °C, 4.0 h and 1.0 MPa N2. The improved activity of basic zirconium carbonate could be attributed to the synergistic effect among acid and base active sites. Furthermore, this low-cost catalyst shows improved thermochemical stability and recyclability under optimal conditions, where no significant decrease in activity was observed after three runs. This catalytic process could be identified as a promising alternative to produce ethyl lactate from renewable biomass and its derivatives.

15.
Zhongguo Gu Shang ; 33(8): 725-9, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32875762

RESUMO

OBJECTIVE: To explore the relationship between obesity and lumbar disc herniation in adolescents. METHODS: From January 2018 to July 2019, 581 patients (337 males, 244 females) with lumbar disc herniation were included in the surgical treatment. According to the age classification standard of the World Health Organization, they were divided into two groups:the adolescent group, 235 cases (145 males, 90 females), age 14 to 44 years old with an average of (32.2±7.3) years. The middle-aged and elderly group, 346 cases (192 males, 154 females), age 45 to 85 years old with an average age of (58.7± 9.8) years. At the time of admission, the same trained investigator measured height, waist circumference and hip circumference with tape measure and weight with electronic scale. All the data were measured twice and the average value was taken and recorded. The body mass index and the waist-hip ratio were calculated. According to each parameter standard, the patients were divided into normal, overweight and obese. The proportion of obese people in different age groups was calculated and analyzed statistically. RESULTS: The normal of the BMI, waist circumference and waist-hip ratio of the young patients were 78(33.2%), 91 (38.7%) and 85(36.2%) respectively;104(44.3%), 95(40.4%), 99(42.1%) were overweight, 53(22.5%), 49(20.9%), 51 (21.7%) were obese. The normal of the BMI, waist circumference and waist-hip ratio of the middle-aged and old patients were 145 (41.9%), 138 (39.9%) and 147 ( 42.5%) respectively;153 (44.2%), 162 (46.8%), 155 (44.8%) were overweight, 48 (13.9%), 46 (13.3%), 44 (12.7%) were obese. Among the three parameters, the proportion of obese people in the adolescent group was higher than that in the middle-aged group, and the difference was significant (χ2 was 8.836, 6.228 7, 8.536 3 respectively, P<0.05). CONCLUSION: For adolescent patients, obesity may increase the load of lumbar disc, affect its metabolism and accelerate its degeneration. For adolescent, obesity is a more significant risk factor of lumbar disc herniation, so it is more important to control weight and prevent obesity in adolescent to reduce the incidence of lumbar disc herniation.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Obesidade , Fatores de Risco , Adulto Jovem
16.
Cancer Manag Res ; 12: 8287-8302, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982424

RESUMO

BACKGROUND: Osteosarcoma (OS) is the most common bone tumor. Many studies have reported that circular RNAs (circRNAs) play an important role in the development of a variety of human cancers. However, the underlying mechanism of circ_0001721 in regulating osteosarcoma progression remains unknown. MATERIALS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the levels of circ_0001721, miR-372-3p, and mitogen-activated protein kinase 7 (MAPK7) in osteosarcoma tissues and cells. Besides, glycolysis was investigated by glucose consumption, lactate production and hexokinase II (HK2) protein level. Cell proliferation and apoptosis were determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry, separately. Cell migration and invasion were determined by transwell assay. Moreover, the protein levels of HK2 and epithelial-to-mesenchymal transition (EMT) markers were determined by Western blot analysis. The relationship between miR-372-3p and circ_0001721 or MAPK7 was predicated by starbase v3.0 and confirmed by dual-luciferase reporter assay or RNA binding protein immunoprecipitation (RIP) assay. Murine xenograft model was established to investigate the role of circ_0001721 in vivo. RESULTS: The levels of circ_0001721 and MAPK7 were upregulated in osteosarcoma tissues and cells, while miR-372-3p was downregulated. Knockdown of circ_0001721 inhibited glycolysis, cell proliferation, cell migration, invasion and epithelial-to-mesenchymal transition (EMT), and promoted apoptosis. Circ_0001721 was validated as a sponge of miR-372-3p and mediated glycolysis, cell proliferation, apoptosis, migration, invasion, and EMT of osteosarcoma cells through miR-372-3p. MAPK7 was a target of miR-372-3p and overexpression of MAPK7 attenuated anti-cancer role of miR-372-3p in OS cells. Further studies revealed that circ_0001721 regulates MAPK7 expression via sponging miR-372-3-p. Finally, knockdown of circ_0001721 inhibited tumor progression in vivo. CONCLUSION: Circ_0001721 promoted osteosarcoma development through the miR-372-3p/MAPK7 axis.

17.
Nano Lett ; 20(5): 3499-3505, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32250634

RESUMO

Plasmonic nanoantennas are capable of reversibly interconverting free-space radiation with localized modes at the nanoscale. However, optical access to a single nanoantenna, through a laser beam, is always accompanied by disruptive background perturbations and heating effects. Remote spectroscopy is one promising route to overcome these effects. Here, we demonstrate excitation-collection-separated enhanced spectroscopy using a matched nanoantenna pair. The receiving and transmitting antennas are geometrically separated but bridged by the propagating surface plasmon polaritons (SPPs) on the metal film. The receiving antenna, consisting of a silver nanowire on a mirror, ensures a high light-to-plasmon conversion efficiency. The transmitting antenna consists of a silver nanocube over a mirror and is impedance matched to free space photons and the propagating SPPs. As a proof-of-principle, we demonstrate remote surface-enhanced Raman scattering with a high signal-to-noise ratio. This matched nanoantenna pair may have applications for remote entanglement of quantum emitters, biochemistry detection, or optical interconnects.

18.
ACS Nano ; 13(12): 14041-14047, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31738504

RESUMO

An electrically driven optical antenna (EDOA) provides a nanoscale light-emitting scheme that is appealing for biosensors, plasmonic displays, and on-chip optoelectronic circuits. The EDOA (consisting of metal nanoparticles (NPs)) excited by inelastic tunneling electrons has attracted broad interest due to its terahertz modulation bandwidth and microelectronics-compatible dimensions. Currently, the efficient fabrication of EDOA is hampered by the ultrasmall size of NPs and the requirement of controllable preparation. Here, we overcome this limitation by accurately positioning thiol-covered gold NPs onto predesigned electrodes using dielectrophoresis trapping. The combination of a high-quality molecule tunnel barrier and the template trapping ensures that the EDOA can operate stably in ambient conditions. More importantly, the template trapping allows fabrication of EDOA with different numbers and arrangements of NPs by controlling the size and orientation of the template. This technology provides a way to fabricate controllable optoelectronic devices based on NPs and is promising for compact and smart photonic devices.

19.
Nano Lett ; 19(6): 3838-3845, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31125243

RESUMO

Developing highly efficient nanoscale coherent light sources is essential for advances in technological applications such as integrated photonic circuits, bioimaging, and sensing. An on-chip wavelength convertor based on second harmonic generation (SHG) would be a crucial step toward this goal, but the light-conversion efficiency would be low for small device dimensions. Here we demonstrate strongly enhanced SHG with a high conversion efficiency of 4 × 10-5 W-1 from a hybrid plasmonic waveguide consisting of a CdSe nanowire coupled with a Au film. The strong spatial overlap of the waveguide mode with the nonlinear material and momentum conservation between the incident and reflected modes are the key factors resulting in such high efficiency. The SHG emission angles vary linearly with excitation wavelength, indicating a nonlinear steering of coherent light emission at the subwavelength scale. Our work is promising for the realization of efficient and tunable nonlinear coherent sources and opens new approaches for efficient integrated nonlinear nanophotonic devices.

20.
Zhongguo Gu Shang ; 32(2): 116-119, 2019 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-30884926

RESUMO

OBJECTIVE: To explore the surgical technique and clinical effect of limited open reduction and intramedullary fixation assisted with orthopedic traction bed for the treatment of femoral subtrochanteric fractures. METHODS: From July 2015 to October 2017, 12 patients with femoral subtrochanteric fractures were treated including 9 males and 3 females with an average age of 44 years old ranging from 33 to 67 years old. Among them, 10 cases were on the left trochanter and 2 on the right, and there were 8 cases of highly fall injury and 4 cases of traffic accident injury. All patients received operation at 2 to 5 days after injury. According to the Seinsheimer classification, 8 cases were type IIIA, 2 were type IIIB and 2 were type IV, and all cases were closed injury. The patients were placed on the orthopedic traction bed for trial closed reduction to maintain proper traction before operation. Under C-arm X-ray fluoroscopy, it was advisable to take the fracture end of the main bone block without obvious shortening and shifting. Then limited incision and lengthened InterTan intramedullary nailing were performed, and the Sanders traumatic hip score was used to evaluate the postoperative efficacy. RESULTS: All 12 patients were followed up from 6 to 24 months with an average of 12 months. All cases were received bone healing at 3 to 6 months with an average time of 4 months. According to the Sanders grades, the results were excellent in 9 cases, good in 2 cases and medium in 1 case. Infection, breakage of internal fixation loosening and adverse complications such as malunion were not appeared in all the cases. CONCLUSIONS: Limited open reduction assisted with traction bed can be effective to solve the problem of the intraoperative reduction in the complex subtrochanteric fractures, which could save operation time and decrease bleeding. Combined with intramedullary fixation, this method could acquire good counterpoint and stability for the fracture end, and provide a method for the treatment of refractory subtrochanteric fractures.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Quadril , Adulto , Idoso , Pinos Ortopédicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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