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Understanding and managing hot electrons in metals are of fundamental and practical interest in plasmonic studies and applications. A major challenge for the development of hot electron devices requires the efficient and controllable generation of long-lived hot electrons so that they can be harnessed effectively before relaxation. Here, we report the ultrafast spatiotemporal evolution of hot electrons in plasmonic resonators. Using femtosecond-resolution interferometric imaging, we show the unique periodic distributions of hot electrons due to standing plasmonic waves. In particular, this distribution can be flexibly tuned by the size, shape, and dimension of the resonator. We also demonstrate that the hot electron lifetimes are substantially prolonged at hot spots. This appealing effect is interpreted as a result of the locally concentrated energy density at the antinodes in standing hot electron waves. These results could be useful to control the distributions and lifetimes of hot electrons in plasmonic devices for targeted optoelectronic applications.
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Manipulating active sites of catalysts is crucial but challenging in catalysis science and engineering. Beyond the design of the composition and structure of catalysts, the confined electromagnetic field in optical cavities has recently become a promising method for catalyzing chemical reactions via strong light-matter interactions. Another form of confined electromagnetic field, the charge density wave in plasmonic cavities, however, still needs to be explored for catalysis. Here, we present an unprecedented catalytic mode based on plasmonic cavities, called plasmonic cavity-catalysis. We achieve direct control of catalytic sites in plasmonic cavities through standing hot carrier waves. Periodic catalytic hotspots are formed because of localized energy and carrier distribution and can be well tuned by cavity geometry, charge density, and excitation angle. We also found that the catalytic activity of the cavity mode increases several orders of magnitude compared with conventional plasmonic catalysis. We ultimately demonstrate that the locally concentrated long-lived hot carriers in the standing wave mode underlie the formation of the catalytic hotspots. Plasmonic cavity-catalysis provides a new approach to manipulate the catalytic sites and rates and may expand the frontier of heterogeneous catalysis.
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Single-nanoparticle electrochemistry offers electrochemical behaviors of individual entities beyond the ensemble system. An electric double layer (EDL) exists on any charged particle-liquid interface because of counter-ion accumulation, while direct measuring of the interfacial ion migration remains a challenge. Herein, a plasmonic-based transient microscopic method, with a temporal resolution of 1-2â µs, was demonstrated to directly track the ion migration dynamics on single charged nanoparticles. We found that the dynamics of EDL formation might deviate significantly from the prediction made by using the classical resistance-capacitance (RC) model under nanoscale and transient conditions. Under ultrafast charging, due to the limit migration rate of ions in the solution, the actual time scale of the EDL formation could be up to 5â times slower than the predicted value from the RC model. We then proposed a new theoretical model to describe the transient dynamics of EDL formation. These results may expand our current knowledge about nano-electrochemistry and transient electrochemistry.
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BACKGROUND: Dexmedetomidine is a highly selective adrenergic receptor agonist, which has a dose-dependent sedative hypnotic effect. Furthermore, it also has pharmacological properties, and the ability to inhibit sympathetic activity and improve cardiovascular stability during an operation. However, its protective effect on patients with severe craniocerebral injury in the perioperative period remains unclear. METHOD: Eighty adult male SD rats were used and divided into two groups (n = 40, each group): dexmedetomidine injury group (experimental group), and sodium chloride injury group (control group). Models of severe craniocerebral injury were established in these two groups using the modified Feeney's free-fall method. As soon as the establishment of models was succeed, rat in the experimental group received 1 µg of dexmedetomidine (0.1 ml), while each rat in the control group was given 0.1 ml of 0.9% sodium chloride. Blood was sampled from an incision at the femoral vein to detect TNF-α and IL-2 levels at 1, 12, 24,36,48 and 72 h after establishing the model in the two groups. RESULTS: After severe craniocerebral injury, TNF-α levels of rats were lower in every stage and at different degrees in the experimental group than in the control group (P < 0.05), while IL-2 levels were lower in the experimental group to different extents (P < 0.05). CONCLUSION: Dexmedetomidine protects the brain of rats with severe craniocerebral injury by reducing the release of inflammatory mediators.
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Agonistas de Receptores Adrenérgicos alfa 2/uso terapéutico , Traumatismos Craneocerebrales/sangre , Traumatismos Craneocerebrales/tratamiento farmacológico , Dexmedetomidina/uso terapéutico , Interleucina-2/sangre , Factor de Necrosis Tumoral alfa/sangre , Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Animales , Biomarcadores/sangre , Dexmedetomidina/farmacología , Interleucina-2/antagonistas & inhibidores , Masculino , Ratas , Ratas Sprague-Dawley , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
A sensitive and specific method using liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) for the determination of pinaverium bromide in human plasma was developed and validated. Pinaverium bromide and an internal standard (paclitaxel) were isolated from plasma samples by precipitating plasma, and determined by LC-MS/MS in multiple-reaction monitoring mode. The main metabolite of pinaverium bromide and endogenous substances in plasma did not show any interference. The calibration curve was linear over the plasma concentration range of 10.0-10000.0 pg/mL with a correlation coefficient of 0.9979. The relative standard derivations intra- and inter-day at 30.0, 300.0 and 8000.0 pg/mL in plasma were less than 15%. The absolute recoveries of pinaverium bromide and the internal standard were 99.7-111.7 and 106.2%, respectively. The lower limit of quantitation was 10 pg/mL. The analytical method was successfully applied to study the pharmacokinetics of pinaverium bromide tablets in healthy Chinese volunteers.
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Cromatografía Liquida/métodos , Morfolinas/sangre , Espectrometría de Masas en Tándem/métodos , Administración Oral , Estudios Cruzados , Estabilidad de Medicamentos , Humanos , Análisis de los Mínimos Cuadrados , Masculino , Morfolinas/administración & dosificación , Morfolinas/farmacocinética , Paclitaxel/sangre , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: Necrotizing fasciitis is a fulminant necrotizing soft tissue disease with a high fatality rate. It always starts with impact on the deep fascia rapidly and might result in secondary necrosis of the subcutaneous tissue, fascia, and muscle. Thus, timely and multiple surgical operations are needed for the treatment. Meanwhile, the damage of skin and soft tissue caused by multiple surgical operations may require dermatoplasty and other treatments as a consequence. CASE SUMMARY: Here, we report a case of 50-year-old male patient who was admitted to our hospital with symptoms of necrotizing fasciitis caused by cryptoglandular infection in the perianal and perineal region. The symptoms of necrotizing fasciitis, also known as the cardinal features, include hyperpyrexia, excruciatingly painful lesions, demonstration gas in the tissue, an obnoxious foul odor and uroschesis. The results of postoperative pathology met the diagnosis. Based on the premise of complete debridement, multiple incisions combined with thread-dragging therapy (a traditional Chinese medicine therapy) and intensive supportive therapies including comprising antibiotics, nutrition and fluids were given. The outcome of the treatment was satisfactory. The patient recovered quickly and achieved ideal anal function and morphology. CONCLUSION: Timely and effective debridement and multiple incisions combined with thread-dragging therapy are an integrated treatment for necrotizing fasciitis.
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A bio-electrochemically (BE) recycling platform was assembled to recover Li and Co from the cathodic materials of spent LIBs in one integrated system. The BE platform consists of three microbial-fuel-cell (MFC) subsystems, including MFC-A, MFC-B, and MFC-C. Co and Li were smoothly recovered from the cathodic materials in the assembled platform. The initial pH and the loading ratios of LiCoO2 both significantly influenced the leaching efficiencies of Li and Co in MFC-A. Approximately 45% Li and 93% Co were simultaneously released through the reduction of LiCoO2 at the initial pH of 1 and the loading ratios of LiCoO2 of 0.2 g/L. The (NH4)2C2O4-modified granular activated carbons (GAC) with a thickness of 1.5 cm was favorably stacked adjacent to the cathode of the MFC-B system. About 98% of removal efficiency (RECo1) and 96% of recovery efficiency (RECo2) of Co were achieved in MFC-B under optimum conditions. The dosing concentration of Li+ lower than 2 mg/L and the (NH4)2CO3 of 0.01-0.02 M were conducive to enhancing the recovery of Li from raffinate and guaranteed the higher power output and coulombic efficiencies in MFC-C. The continuous release of CO2 caused by exoelectrogenic microorganisms on the biofilm facilitated the precipitation of Li2CO3.
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Suministros de Energía Eléctrica , Litio , Electrodos , Iones , ReciclajeRESUMEN
An inadvertent leakage of 90Sr into the environment can induce an easy accumulation in biosphere and cause a continuous radiation to the surrounding ecosystem. In this study, sodium hexametaphosphate (Na6O18P6) was employed to modify the blast furnace slags (BFS) to enhance the chemical stabilization of Sr2+ ions in the BFS-based cementitious materials. Microwave irradiation (MW) was used to further increase the binder activity of BFS samples and strengthened the mechanical strengths and durability of BFS-based blocks. A combination of experimental factors including the mass ratio of Na6O18P6 to BFS-Sr0.1 of 15%, the ratio of solid to liquid of 1:4â¯mg/L, the output power of 650â¯W, and the activation time of 3â¯min was most conductive to achieving an optimal microwave-irradiation process. Four extraction solutions were sorted by their leaching abilities following as MgSO4 solutionâ¯>â¯H2SO4 solutionâ¯>â¯CH3OOH solutionâ¯>â¯deionized (DI) water based on their leaching results. Compared with microwave irradiation, an addition of Na6O18P6 to BFS samples obtained a better compressive strength for BFS-based blocks. However, a microwave-irradiation treatment was more effective in improving the resistances of blocks to gamma irradiation and thermal-thaw changes. Exposing to gamma irradiation over 6 months and enduring to thermal-thaw tests over 15 cycles, the microwave-treated blocks only lost 3.29% and 2.23% of leaching removal efficiencies in deionized water, respectively. Microwave irradiation increased the mechanical strengths of BFS-based blocks and inhibited leaching of Sr2+ ions from matrices mainly by strengthening hydration reactions and Sr2+ encapsulation.
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Microondas , Modelos Químicos , Fosfatos/química , Estroncio/química , Álcalis , Fuerza Compresiva , Ecosistema , AguaRESUMEN
AIM: To investigate the reversal effect of LY980503, a benflumetol derivative, on multidrug resistance in vincristine (VCR) -resistant human gastric carcinoma cell line SGC7901/VCR. METHODS: Cells of a human gastric cancer cell line, SGC7901, and its VCR-resistant variant, SGC7901/VCR, were cultivated with LY980503 and /or doxorubicin (DOX). The cytotoxicity of drugs in vitro was assayed by MTT method. Based on the flow cytometric technology, the uptake of DOX was detected in these cells by measuring DOX-associated mean fluorescence intensity (MFI). RESULTS: SGC7901/VCR cells were 23.5 times more resistant to DOX in comparison with SGC7901 cells. LY980503 at the concentrations of 2.0 micromol/L-10 micromol/L had no obvious cytotoxicity to SGC7901 and SGC7901/VCR cells. After simultaneous treatment with LY980503 at the concentrations of 2.0, 4.0 and 10 micromol/L, the IC(50) of DOX to SGC7901/VCR cells decreased from 1.6 +/- 0.12 micromol/L to 0.55 +/- 0.024, 0.25 +/- 0.032 and 0.11 +/- 0.015 micromol/L, respectively, thus, increasing the DOX sensitivity by 2.9-fold (P < 0. 05), 6.4-fold (P < 0. 01) and 14.5-fold (P < 0. 01), respectively. In the uptake study of DOX, simultaneous incubation of SGC7901/VCR cells with LY980503 significantly increased the DOX -associated MFI in SGC7901/VCR cells. No such results were found in parental SGC7901 cells. CONCLUSION: LY980503 at non-cytotoxic concen-trations can effectively circumvent resistance of SGC7901/VCR cells to DOX by increasing intracellular DOX accumulation.
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Antineoplásicos Fitogénicos/farmacología , Resistencia a Múltiples Medicamentos/fisiología , Etanolaminas/farmacología , Fluorenos/farmacología , Neoplasias Gástricas/tratamiento farmacológico , Vincristina/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/fisiología , Humanos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/fisiopatologíaRESUMEN
This paper reports the diagnosis and therapy of one case of Dipylidium caninum infection in an infant.
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Cestodos/fisiología , Infecciones por Cestodos/diagnóstico , Infecciones por Cestodos/tratamiento farmacológico , Animales , Infecciones por Cestodos/transmisión , Humanos , Lactante , MasculinoRESUMEN
For the Shanghai Synchrotron Radiation Facility (SSRF) and future Shanghai Free-Electron Laser projects, ground vibration is an important factor and, in order to attenuate it, the construction of a deep tunnel is under consideration. This paper concentrates on the investigation of ground vibration at different underground levels down to 60 m below surface, in order to understand the effect of vibration attenuation with depth. The effect of traffic is also studied using a 10 ton truck, with ground motion compared in different directions. Finally, a summary and some suggestions on these two projects are given.