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Background: Mutations in parkin have been associated with autosomal recessive early-onset Parkinson's disease (PD). Here, we report on unusual phenotypic variability within a family with mutations in parkin. Methods: The proband and her parents were clinically assessed. Mutation analysis was performed using genomic DNA and complementary DNA. The protein expression of Parkin and Mitofusin 2 was examined by western blotting. Results: The proband was a compound heterozygote with no detectable Parkin and presented with early-onset PD. The father, a single heterozygote with reduced expression of Parkin, had mild loss of arm swing. The mother, who had only very mild rigidity, was unexpectedly found to be a homozygote with no Parkin expression. The proband, but not the parents, met the Queen Square Brain Bank criteria for PD. Parkin-dependent ubiquitination of Mitofusin 2 was impaired in the mother and the proband. Conclusion: We report the first case of a homozygous mutation carrier in parkin who had no functional protein and only mild signs of parkinsonism in her seventh decade, whereas her daughter developed typical early-onset PD. This family demonstrates phenotypic variability in parkin-related parkinsonism. © 2012 Movement Disorder Society

We present here, the results of a thorough study of the longitudinal permeability ratio (LPR) and transverse permeability ratio (TPR) in sputtered Co 19.35 Fe 53.28 Hf 7.92 O 19.35 films with varying thicknesses (t = 1, 1.5, 1.8 and 2.4 μm) in the frequency range of 100 - 1000 MHz. It is found that for all samples investigated, the LPR/TPR first increases with increasing frequency, reaches a maximum at 710 MHz, and then decreases at higher frequencies. This is related to the ferromagnetic resonance. The LPR and TPR profiles measured along the easy axis of the film show a single-peak feature, whereas those measured along the hard axis of the film show a double-peak one. This indicates an existence of magnetic anisotropy and its dispersion in the films. It reveals that the study of LPR and TPR spectra provides an alternative way for the evaluation of the high-frequency magnetic softness of film-type materials.

Influence of film thickness on the soft magnetic properties of Co19.35Fe53.28Hf7.92O19.35 films, which were deposited on Si(100) substrates using the oxygen reactive RF-sputtering method, has been thoroughly investigated. It is found that as the film thickness (t) increases from 50 to 430 nm, the easy-axis coercivity (HCE) strongly decreases from 26.2 to 1.5 Oe, while the hard-axis anisotropy field (HKH) significantly increases from 68.7 to 84.8 Oe and the saturation magnetization (4πMs) tends to increase from 16.8 to 19.7 kG. As t exceeds 430 nm, HKH gradually decreases, while both HCE and 4πMs remain almost unchanged. It reveals that a strong phase separation appears to occur in films with t > 430 nm, resulting in the decrease of HKH. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Research Center for Advanced Magnetic Materials, Chungnam National University, Daejeon 305-764, South Korea Received 7 May 2007, revised 30 October 2007, accepted 31 October 2007 Published online 18 December 2007 PACS 75.70.Ak, 85.70.Kh Influence of film thickness (t) on the electrical and magnetic properties of Co–Fe–Al–O films has been systematically investigated via means of vibrating sample magnetometry (VSM), permeability spectra and magneto-optical Kerr effect (MOKE). It is found that the electrical resistivity (ρ) decreases as the film thickness increases; ρ = 412.5 µΩcm for the t = 600 nm sample decreases to ρ = 368.2 µΩcm for the t = 1200 nm sample. The coercive force, measured along the easy-axis direction, decreases as the film thickness increases. Interestingly, along the hard-axis magnetization direction, the magnetic hysteresis loop is reversed and the coercive force is negative for the t = 600 and 800 nm samples. However, this pe-culiar feature disappears as t reaches 1200 nm, which is probably attributed to the microstructural change with respect to changes of film thickness. At a frequency of 1GHz, the hard-axis effective permeability decreases from 1252 to 1000 as the film thickness increases from 600 to 1200 nm, respectively. The VSM and MOKE results reveal an increase in magnetic anisotropy in the near-surface region of the film.

This paper reports on the excellent high-frequency magnetic performance of Co-Fe-Hf-O thin films, which were deposited on Si(100) substrates by the oxygen reactive rf-sputtering method. It was shown that the films possessed not only high electrical resistivity but also large saturation magnetization and hard-axis anisotropy field. Among the compositions investigated, Co 19.35 Fe 53.28 Hf 7.92 O 19.35 exhibited the ultrasoft magnetic properties of high saturation magnetization, 4πM s ∼19.86 kG, and low coercivity, H c ∼1.5 Oe. The magnetic permeability remained almost constant up to 3 GHz and reached a maximum at the ferromagnetic resonant frequency of 4.024 GHz. These properties of this film together with a high electrical resistivity of 3569 μΩcm make it ideal for producing micromagnetic devices for high-frequency applications.

The high-frequency giant magnetoimpedance (GMI) effect in a Co47.5Fe21.9Al17.2O15.2 thin film was systematically investigated. In the frequency range of 100–500 MHz, GMI profiles showed a double-peak characteristic, reflecting an evident existence of the transverse magnetic anisotropy in the film, which coincided with the magnetization data. Interestingly, there was an anomalous transformation in the GMI profile from “positive” to “negative” and this was associated with the complex phase transformation of permeability. The GMI ratio decreased with decreasing film-thickness, due to an increase of the electrical resistivity and a decrease of the magnetic softness. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Fe-Al-O thin films exhibit good magnetic properties. However, their application in RF devices is mainly restricted by the low ferromagnetic resonance frequency. For practical applications it would be useful to try to shift this frequency to higher regions by exploiting the extra anisotropy induced by patterning the film. In this work, we discuss a model describing the permeability behavior as a function of frequency in patterned film samples and apply this model to explain experimental results for patterned Fe 87.3 Al 4.2 O 8.5 thin films.

The exchange bias (HE) coupling in MnCr/Co bilayers has been analysed. The exchange bias and coercivity (Hc) of the samples were investigated as a function of temperature. They reached the largest value for an annealing temperature of 300 °C at a measuring temperature of 123 K. Moreover, HE and Hc also exhibited a dependence on the thickness of ferromagnetic and antiferromagnetic layers. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The effect of microstructures on the electrical and magnetic properties of Co-Fe-Al-O thin films was studied using X-ray diffraction (XRD) analysis and conventional transmission electron microscopy (TEM). The results showed that excellent soft magnetic properties were associated with granular nanoscale grains of α-CoFe and α-Co(Fe) phases. The introduction of aluminium and oxygen to CoFe films led to a refinement of the granular microstructure. When the partial pressure of oxygen was less than 4%, oxide particles CoFe 2 O 4 , CoAl 2 O 4 or FeAl 2 O 4 were embedded in α-CoFe, α-Co(Fe) grains. A higher partial pressure of oxygen changed the crystalline oxide to amorphous oxide, resulting in the formation of smaller grains of α-CoFe and α-Co(Fe) phases. The partial pressure of oxygen caused drastic changes in the coercivity (H c ), anisotropy field (H k ), and electrical resistivity (p), the reason for which was discussed based on the microstructural observations and X-ray diffraction results. Co-Fe-Al-O thin films exhibit excellent high frequency characteristics: an effective permeability larger than 1000 and stability above 1 GHz.

Neurodegenerative diseases, notably Alzheimer's and Parkinson's diseases, are amongst the most devastating disorders afflicting the elderly. Currently, no curative treatments or treatments that interdict disease progression exist. Over the past decade, immunization strategies have been proposed to combat disease progression. Such strategies induce humoral immune responses against misfolded protein aggregates to facilitate their clearance. Robust adaptive immunity against misfolded proteins, however, accelerates disease progression, precipitated by induced effector T cell responses that lead to encephalitis and neuronal death. Since then, mechanisms that attenuate such adaptive neurotoxic immune responses have been sought. We propose that shifting the balance between effector and regulatory T cell activity can attenuate neurotoxic inflammatory events. This review summarizes advances in immune regulation to achieve a homeostatic glial response for therapeutic gain. Promising new ways to optimize immunization schemes and measure their clinical efficacy are also discussed.