Enhanced second-harmonic generation from magnetic resonance in AlGaAs nanoantennas

We designed AlGaAs-on-aluminium-oxide all-dielectric nanoantennas with magnetic dipole resonance at near-infrared wavelengths

Dynamics of two coupled vortices in a spin valve nanopillar excited by spin transfer torque

We investigate the dynamics of two coupled vortices driven by spin transfer. We are able to independently control with current and perpendicular field, and to detect, the respective chiralities and polarities of the two vortices. For current densities above $J=5.7*10^7 A/cm^2$, a highly coherent signal (linewidth down to 46 kHz) can be observed, with a strong dependence on the relative polarities of the vortices. It demonstrates the interest of using coupled dynamics in order to increase the coherence of the microwave signal. Emissions exhibit a linear frequency evolution with perpendicular field, with coherence conserved even at zero magnetic field

Optimization of microesclerotia production by Trichoderma asperellum.

The Trichoderma genus, despite its widespread use for decades as a biological control in agriculture, has only recently been gaining a share in the biopesticide market, thanks to its versatility in controlling diseases and acting as a plant growth enhancer. Most Trichoderma's commercial products have aerial conidia as active ingredient, but recent studies report the production of another propagule, more robust for formulation and application under field conditions - the microsclerotia (MS). Thus, our objective was to evaluate the nutritional conditions that favor the greater production of MS, using two cultures of T. asperellum with known antagonistic activity. For this, we used the fractional factorial design approach in which we evaluated 5 variables: Carbon source, Carbon concentration, C:N ratio, Strain, Nitrogen source, all influencing the production of MS. The results indicated that all variables were statistically significant to MS production. In the best condition tested, we obtained values higher than 104 MS mL-1. In conclusion that the conditions found for the production of MS, using sucrose and lyscell, with carbon concentration 20 g L-1 and C:N ratio (10:1) and isolate TR 356, are inexpensive carbon and nitrogen sources may allow us to scale-up this biofungicide

Identification and selection rules of the spin-wave eigen-modes in a normally magnetized nano-pillar

We report on a spectroscopic study of the spin-wave eigen-modes inside an individual normally magnetized two layers circular nano-pillar (Permalloy$|$Copper$|$Permalloy) by means of a Magnetic Resonance Force Microscope (MRFM). We demonstrate that the observed spin-wave spectrum critically depends on the method of excitation. While the spatially uniform radio-frequency (RF) magnetic field excites only the axially symmetric modes having azimuthal index $\ell=0$, the RF current flowing through the nano-pillar, creating a circular RF Oersted field, excites only the modes having azimuthal index $\ell=+1$. Breaking the axial symmetry of the nano-pillar, either by tilting the bias magnetic field or by making the pillar shape elliptical, mixes different $\ell$-index symmetries, which can be excited simultaneously by the RF current. Experimental spectra are compared to theoretical prediction using both analytical and numerical calculations. An analysis of the influence of the static and dynamic dipolar coupling between the nano-pillar magnetic layers on the mode spectrum is performed

Optimizing magneto-dipolar interactions for synchronizing vortex based spin-torque nano-oscillators

We report on a theoretical study about the magneto-dipolar coupling and synchronization between two vortex-based spin-torque nano-oscillators. In this work we study the dependence of the coupling efficiency on the relative magnetization parameters of the vortices in the system. For that purpose, we combine micromagnetic simulations, Thiele equation approach, and analytical macro-dipole approximation model to identify the optimized configuration for achieving phase-locking between neighboring oscillators. Notably, we compare vortices configurations with parallel (P) polarities and with opposite (AP) polarities. We demonstrate that the AP core configuration exhibits a coupling strength about three times larger than in the P core configuration.Comment: 8 pages, 11 figure

Vinorelbine-based chemotherapy in hormone refractory prostate cancer

Background: No consensus exists regarding further therapy for the management of hormone-refractory prostate cancer. In this phase II study, the combination of Vinorelbine with 5-Fluorouracil and folinic acid (FLN regimen) was evaluated in patients with progressive or resistant disease after hormone therapy. Patients and Methods: Thirty-four patients were treated with Vinorelbine at a dose of 20 mg/m 2 intravenously (i.v.) on days 1 and 3, folinic acid (FA), 100 mg/m 2 i.v. and 5-Fluorouracil (5-FU), 350 mg/m 2 i.v. as a short infusion on days 1 to 3. The therapy was given in an out-patient setting, every 3 weeks. Results: All of the 34 eligible patients were evaluable for toxicity and 30 for activity. A total of 127 cycles was administered (91% at full dose). Among the 15 patients with measurable disease, four had a partial response (26.6%; C.I. 95%, 28.3% to 65.7%) and four achieved stable disease. In 14 patients (47%) a clinical benefit was documented. Six out of 15 patients with bone-only involvement had stable disease (40%). The median duration of stabilization and partial response was 16 weeks (range 4-24 weeks). The most common toxicity was hematological: Grade 4 (NCI-CTC scale) in five patients at re-cycle. Other toxicities were of low incidence and easy to manage. Conclusion: The encouraging results obtained with the FLN regimen in terms of clinical benefit and its predictable and manageable toxicity support the palliative role of this chemotherapeutic strategy in hormone-refractory prostate patients

Perfect and robust phase-locking of a spin transfer vortex nano-oscillator to an external microwave source

We study the synchronization of the auto-oscillation signal generated by the spin transfer driven dynamics of two coupled vortices in a spin-valve nanopillar to an external source. Phase-locking to the microwave field hrf occurs in a range larger than 10% of the oscillator frequency for drive amplitudes of only a few Oersteds. Using synchronization at the double frequency, the generation linewidth is found to decrease by more than five orders of magnitude in the phase-locked regime (down to 1 Hz, limited by the resolution bandwidth of the spectrum analyzer) in comparison to the free running regime (140 kHz). This perfect phase-locking holds for frequency detuning as large as 2 MHz, which proves its robustness. We also analyze how the free running spectral linewidth impacts the main characteristics of the synchronization regime