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A nonparametric approach to the identification of magnetic anisotropies in ferromagnetic nanostructures is applied in order to study the influence of the bath acidity on the induced magnetic anisotropies in electrodeposited ferromagnetic nanowires. By using partial first order reversal curves (pFORC), we find a two-peak probability density function whose topology changes with the acidity of the electrodeposition bath. Numerical micromagnetic simulations suggest that this particular distribution originates in two populations of nonidentical nanowires with different magneto-crystalline anisotropies. Bath acidity values influence the balance between these two populations rather than the intrinsic properties of individual nanowires. [ABSTRACT FROM AUTHOR]

Abstract: Good quality strontium ruthenate (SrRuO3) thin continuous films (15 to 125 nm thick) have been synthesized on silicon (100) substrates by room temperature pulsed laser deposition under vacuum followed by a post-deposition annealing, a route unexplored and yet not reported for SrRuO3 film growth. The presence of an interfacial Sr2SiO4 layer has been identified for films annealed at high temperature, and the properties of this interface layer as well as the properties of the SrRuO3 film have been analyzed and characterized as a function of the annealing temperature. The room temperature resistivity of the SrRuO3 films deposited by laser ablation at room temperature and post-annealed is 2000 μΩ·cm. A critical thickness of 120 nm has been determined above which the influence of the interface layer on the resistivity becomes negligible. [Copyright &y& Elsevier]

We evaluated the clinical performance of the Bio-Rad Dx CT/NG/MG assay for the detection of Chlamydia trachomatis, Mycoplasma genitalium and Neisseria gonorrhoeae in urogenital samples in comparison with the Roche COBAS® TaqMan® CT assay for C. trachomatis and an in-house TaqMan PCR assay for M. genitalium. Swab specimens were cultured for N. gonorrhoeae. In this prospective study, urogenital samples were obtained from symptomatic and asymptomatic patients attending the sexually transmitted disease clinic of Bordeaux, France, from January to April 2010. A total of 658 clinical specimens (259 male and 180 female urines, 191 vaginal, 21 endocervical and 7 urethral swabs) from 453 patients were analyzed. The prevalence of C. trachomatis and M. genitalium infections was 8.1% (21/260) and 1.9% (5/260) in men and 10.4% (20/193) and 2.1% (4/193) in women, respectively. The Bio-Rad Dx CT/NG/MG clinical sensitivity was 100% for C. trachomatis and M. genitalium in men and women. In male urine, the clinical specificity was 99.6% for C. trachomatis and 100% for M. genitalium. In women, the specificity was 99.5% for swabs and 100% for urines for detecting C. trachomatis and M. genitalium. All seven N. gonorrhoeae PCR-positive samples were also positive by culture. Patients were co-infected in 5/57 cases (8.8%), with C. trachomatis and M. genitalium in three cases, and C. trachomatis and N. gonorrhoeae in two cases. In conclusion, the Bio-Rad Dx CT/NG/MG assay can be recommended for the simultaneous detection of C. trachomatis, M. genitalium and N. gonorrhoeae in urogenital specimens of symptomatic and asymptomatic individuals., (Copyright © 2012 Elsevier B.V. All rights reserved.)

We developed a real-time High Resolution Melting PCR to identify the new Swedish variant of Chlamydia trachomatis ncCT. Of 1191 urogenital specimens C. trachomatis-positive by an omp1 real-time PCR, collected in France in 2007-2008, 1128 gave an interpretable profile corresponding to the wild-type strain; no nvCT was found. This test can be used on selected C. trachomatis-positive samples to monitor the nvCT spread.

Digital microfluidics based on electrowetting-on-dielectric (EWOD) has recently emerged as one of the most promising technologies to realize integrated and highly flexible lab-on-a-chip systems. In such EWOD-based digital microfluidic devices, the aqueous droplets have traditionally been manipulated either directly in air or in an immiscible fluid such as silicone oil. However, both transporting mediums have important limitations and neither offers the flexibility required to fulfil the needs of several applications. In this paper, we report on an alternative mode of operation for EWOD-based devices in which droplets enclosed in a thin layer of oil are manipulated in air. We demonstrate the possibility to perform on-chip the fundamental fluidic operations by using such water-oil core-shell droplets and compare systematically the results with the traditional approach where the aqueous droplets are manipulated directly in air or oil. We show that the core-shell configuration combines several advantages of both the air and oil mediums. In particular, this configuration not only reduces the operation voltage of EWOD-based devices but also leads to higher transport velocities when compared with the manipulation of droplets directly in air or oil.

A novel method combining wet chemistry for synthesis of an Fe core, 532 nm laser irradiation of Fe nanoparticles and Au powder in liquid medium for deposition of an Au shell, and sequential magnetic extraction/acid washing for purification has been developed to fabricate oxidation-resistant Fe@Au magnetic core-shell nanoparticles. The nanoparticles have been extensively characterized at various stages during and up to several months after completion of the synthesis by a suite of electron microscopy techniques (HRTEM, HAADF STEM, EDX), X-ray diffraction (XRD), UV-vis spectroscopy, inductively coupled plasma atomic emission spectroscopy, and magnetometry. The surface plasmon resonance of the Fe@Au nanoparticles is red shifted and much broadened as compared with that of pure colloidal nano-gold, which is explained to be predominantly a shell-thickness effect. The Au shell consists of partially fused approximately 3-nm-diameter fcc Au nanoparticles (lattice interplanar distance, d = 2.36 A). The 18-nm-diameter magnetic core is bcc Fe single domain (d = 2.03 A). The nanoparticles are superparamagnetic at room temperature (300 K) with a blocking temperature, T(b), of approximately 170 K. After 4 months of shelf storage in normal laboratory conditions, their mass magnetization per Fe content was measured to be 210 emu/g, approximately 96% of the Fe bulk value.