Novel mechanisms for electromagnetic wave emission in the terahertz frequency regime emerging at the nanometer scale have recently attracted intense attention for the purpose of searching ...next-generation broadband THz emitters. Here, we report broadband THz emission, utilizing the interface inverse Rashba-Edelstein effect. By engineering the symmetry of the Ag/Bi Rashba interface, we demonstrate a controllable THz radiation (∼0.1-5 THz) waveform emitted from metallic Fe/Ag/Bi heterostructures following photoexcitation. We further reveal that this type of THz radiation can be selectively superimposed on the emission discovered recently due to the inverse spin Hall effect, yielding a unique film thickness dependent emission pattern. Our results thus offer new opportunities for versatile broadband THz radiation using the interface quantum effects.
Melatonin and its receptors have been detected in the ovary of many species, and mediate ovarian functions. The present study was designed to investigate the expression and subcellar location of ...melatonin receptors in bovine granulosa cells (GCs), using reverse transcription (RT) polymerase chain reaction, Western blot, and immunofluorescence analyses. Furthermore, expression level of melatonin receptors mRNA (real-time polymerase chain reaction) after treatment with various concentrations of melatonin, as well as its effects on cell apoptosis, proliferation, and steroidogenesis (by flow cytometry and RIA), were determined. In bovine GCs, melatonin receptors MT1 and MT2 were differentially located at the cell membrane, the cytoplasm, and nuclear membranes. The expression of MT1 and MT2 mRNA was regulated differently by melatonin in time- and dose-dependent manners. Exogenous melatonin suppressed cell apoptosis (P < 0.05) but not proliferation (P > 0.05). After 72 h, the apoptotic rate was significantly inhibited in all treatment groups. Meanwhile, melatonin supplementation stimulated progesterone production, but inhibited estradiol biosynthesis, in a time-dependent manner. Progesterone production was highest (P < 0.05) at 72 h. Estradiol concentrations were almost unaffected (P > 0.05) at 24 h, but were decreased (P < 0.05) at 48 h. In conclusion, exogenous melatonin acts via receptors and has important roles in regulation of development and function of bovine GCs.
We report on nano-infrared (IR) imaging studies of confined plasmon modes inside patterned graphene nanoribbons (GNRs) fabricated with high-quality chemical-vapor-deposited (CVD) graphene on Al2O3 ...substrates. The confined geometry of these ribbons leads to distinct mode patterns and strong field enhancement, both of which evolve systematically with the ribbon width. In addition, spectroscopic nanoimaging in the mid-infrared range 850–1450 cm–1 allowed us to evaluate the effect of the substrate phonons on the plasmon damping. Furthermore, we observed edge plasmons: peculiar one-dimensional modes propagating strictly along the edges of our patterned graphene nanostructures.
Background and purpose
Orolingual angioedema (OA) is an uncommon but potentially life‐threatening complication of treatment with recombinant tissue plasminogen activator (rt‐PA; alteplase) during ...acute ischaemic stroke. This study aimed to determine the incidence of rt‐PA‐related OA in an Asian stroke population and the risk of pre‐stroke anti‐hypertensive drug use for development of this complication.
Methods
A multi‐center stroke registry was used to identify the pre‐stroke medications of acute ischaemic stroke patients receiving intravenous rt‐PA from January 2002 to December 2013. The clinical manifestations of rt‐PA‐related OA were recorded and the incidence of this complication was determined. The risks of pre‐stroke use of different anti‐hypertensive agents for the occurrence of rt‐PA‐related OA were determined from this study and from a meta‐analysis.
Results
A total of 559 patients received intravenous rt‐PA over a 12‐year period. Five patients (two males) developed OA after rt‐PA administration. The incidence of OA amongst these patients was 0.89% (95% confidence interval 0.29%–2.09%), which was lower than that obtained by meta‐analysis (1.9%). Amongst pre‐stroke anti‐hypertensive medications, angiotensin‐converting enzyme (ACE) inhibitors were found in this study to have the highest relative risk for rt‐PA‐related OA (17.1; 95% confidence interval 3.0–96.9). Meta‐analysis also revealed that pre‐stroke use of ACE inhibitors was associated with a high relative risk of OA after intravenous rt‐PA (12.9; 95% confidence interval 4.5–37.0).
Conclusions
The incidence of rt‐PA‐related OA in the Asian population is lower than that in the Caucasian population. Pre‐stroke use of ACE inhibitors significantly increases the risk of this complication.
Element isotopes are characterized by distinct atomic masses and nuclear spins, which can significantly influence material properties. Notably, however, isotopes in natural materials are homogenously ...distributed in space. Here, we propose a method to configure material properties by repositioning isotopes in engineered van der Waals (vdW) isotopic heterostructures. We showcase the properties of hexagonal boron nitride (hBN) isotopic heterostructures in engineering confined photon-lattice waves-hyperbolic phonon polaritons. By varying the composition, stacking order, and thicknesses of h
BN and h
BN building blocks, hyperbolic phonon polaritons can be engineered into a variety of energy-momentum dispersions. These confined and tailored polaritons are promising for various nanophotonic and thermal functionalities. Due to the universality and importance of isotopes, our vdW isotope heterostructuring method can be applied to engineer the properties of a broad range of materials.
We report a nanoinfrared (IR) imaging study of the localized plasmon resonance modes of graphene nanoribbons (GNRs) using a scattering-type scanning near-field optical microscope (s-SNOM). By ...comparing the imaging data of GNRs that are aligned parallel and perpendicular to the in-plane component of the excitation laser field, we observed symmetric and asymmetric plasmonic interference fringes, respectively. Theoretical analysis indicates that the asymmetric fringes are formed due to the interplay between the localized surface plasmon resonance (SPR) mode excited by the GNRs and the propagative surface plasmon polariton (SPP) mode launched by the s-SNOM tip. With rigorous simulations, we reproduce the observed fringe patterns and address quantitatively the role of the s-SNOM tip on both the SPR and SPP modes. Furthermore, we have seen real-space signatures of both the dipole and higher-order SPR modes by varying the ribbon width.
By designing a structured gas density profile between the dual-stage gas jets to manipulate electron seeding and energy chirp reversal for compressing the energy spread, we have experimentally ...produced high-brightness high-energy electron beams from a cascaded laser wakefield accelerator with peak energies in the range of 200-600 MeV, 0.4%-1.2% rms energy spread, 10-80 pC charge, and ∼0.2 mrad rms divergence. The maximum six-dimensional brightness B_{6D,n} is estimated as ∼6.5×10^{15} A/m^{2}/0.1%, which is very close to the typical brightness of e beams from state-of-the-art linac drivers. These high-brightness high-energy e beams may lead to the realization of compact monoenergetic gamma-ray and intense coherent x-ray radiation sources.
We propose a discrete transition-based reweighting analysis method (dTRAM) for analyzing configuration-space-discretized simulation trajectories produced at different thermodynamic states ...(temperatures, Hamiltonians, etc.) dTRAM provides maximum-likelihood estimates of stationary quantities (probabilities, free energies, expectation values) at any thermodynamic state. In contrast to the weighted histogram analysis method (WHAM), dTRAM does not require data to be sampled from global equilibrium, and can thus produce superior estimates for enhanced sampling data such as parallel/simulated tempering, replica exchange, umbrella sampling, or metadynamics. In addition, dTRAM provides optimal estimates of Markov state models (MSMs) from the discretized state-space trajectories at all thermodynamic states. Under suitable conditions, these MSMs can be used to calculate kinetic quantities (e.g., rates, timescales). In the limit of a single thermodynamic state, dTRAM estimates a maximum likelihood reversible MSM, while in the limit of uncorrelated sampling data, dTRAM is identical to WHAM. dTRAM is thus a generalization to both estimators.
Background and purpose
The pharmacologic effects of pioglitazone on the incidence of Parkinson disease (PD) are not clear. No study has examined the interaction between pioglitazone and statin ...treatment on prevention of PD. This study analyzed the associations between pioglitazone, statins, and the incidence of PD in patients with diabetes mellitus (DM) in Taiwan.
Methods
We used the National Health Insurance database from 1996 to 2013. DM and PD were diagnosed according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. We used the propensity score‐matching method to match the study groups. Cox regression analyses were employed to calculate the relative risk of the incidence of PD.
Results
There were 48 828 patients matched and categorized equally into the pioglitazone group and the non‐pioglitazone group. The number of PD patients in the pioglitazone group and the non‐pioglitazone group was 275 (1.1%) and 417 (1.7%), respectively. The pioglitazone group had a lower incidence of PD, with an adjusted hazard ratio (aHR) of 0.66 95% confidence interval (CI): 0.57–0.78, and this benefit was dose‐dependent. Of note, as compared with either pioglitazone or statin treatment, our results first showed that the combination of pioglitazone and statins further lowered the risk of PD, with an aHR of 0.78 (95% CI: 0.64–0.94; P = 0.010).
Conclusions
Our study results suggested that pioglitazone could be a promising agent for reducing the incidence of PD in patients with DM, and works synergistically with statins.
Pioglitazone and statins may lower the indidence of Parkinsion disease independently and synergistically in patients with diabetes mellitus.
PDF
