Accepting its random coil nature allows a partial NMR assignment of the neuronal Tau protein

A combined strategy to obtain a partial NMR assignment of the neuronal Tau protein is presented. Confronted with the extreme spectral degeneracy that the spectrum of this 441 amino acid long unstructured protein presents, we have introduced a graphical procedure based on residue type-specific product planes. Combining this strategy with the search for pairwise motifs, and combining the spectra of different Tau isoforms and even of peptides derived from the native sequence, we arrive at a partial assignment that is sufficient to map the interactions of Tau with its molecular partners. The obtained assignments equally confirm the absence of regular secondary structure in the isolated protein.     

Self-assembled monolayers for electrode fabrication and efficient threshold voltage control of organic transistors with amorphous semiconductor layer

In this paper we show that thiolated self-assembled monolayers (SAMs) can be used to anchor source–drain gold electrodes on the substrate, leading to excellent electrical performances of the organic field-effect transistor (OFET) on a par with those using a standard electrode process. Using an amorphous semiconductor and a gate dielectric functionalized with SAMs bearing different dipole moments, we demonstrate that we can tune the threshold voltage alone, while keeping nearly unchanged the other electrical properties (hole carrier mobility, I_on/I_off ratio, subthreshold swing). This differs from previous studies for which SAMs functionalization induced significant changes in all the OFET electrical performances. This result opens doors to design organic circuits using reproducible amorphous semiconductor based OFETs for which only the threshold voltage can be tuned on demand.     

Iron deficiency anemia following prenatal nutrition interventions.

PURPOSE: Iron deficiency anemia (IDA) during pregnancy and infancy is still common in developed countries, especially in low-income groups. We examined the prevalence of anemia and IDA in healthy low-income pregnant women participating in the Early Childhood Initiatives (ECI) program, and in their infants when they reached six months of age. METHODS: Pregnant women were recruited by nutritionists. In mothers, hemoglobin (Hb), mean corpuscular volume, and serum ferritin (SF) were measured at 36 +/- 2 weeks of gestation. In infants, Hb, mean corpuscular volume, SF, serum iron, total iron binding capacity (TIBC), and transferrin saturation (TS) were measured at six months of age. Thirty-one mother-infant pairs participated. RESULTS: Among the 31 pregnant women participating in the ECI program, six (19.4%) were anemic (Hb <110 g/L) and five (16.1%) suffered from IDA (Hb <110 g/L and SF <10 microg/L). Among infants, seven of 23 (30.4%) were anemic (Hb <110 g/L) and five of 23 (21.7%) suffered from IDA (Hb <110 g/L plus two of the following: TIBC >60 micromol/L, SF <10 microg/L, serum iron <5.3 micromol/L, TS < or = 15%). CONCLUSIONS: The prevalence of anemia in this group of low-income pregnant women is comparable to that in privileged women. The prevalence of IDA in infants is comparable to that observed in other high-risk groups. Effective strategies are needed to prevent IDA in vulnerable groups.     

Non-destructive examination of the bonding interface in DEMO divertor fingers

Plasma facing components (PFCs) with tungsten (W) armor materials for DEMO divertor require a high heat flux removal capability (at least 10 MW/m² in steady-state conditions). The reference divertor PFC concept is a finger with a tungsten tile as a protection and sacrificial layer brazed to a thimble made of tungsten alloy W – 1% La₂O₃ (WL10). Defects may be located at the W thimble to W tile interface. As the number of fingers is considerable (>250,000), it is then a major issue to develop a reliable control procedure in order to control with a non-destructive examination the fabrication processes. The feasibility for detecting defect with infrared thermography SATIR test bed is presented. SATIR is based on the heat transient method and is used as an inspection tool in order to assess component heat transfer capability. SATIR tests were performed on fingers integrating or not the complex He cooling system (steel cartridge with jet holes). Millimeter size artificial defects were manufactured and their detectability was evaluated. Results of this study demonstrate that the SATIR method can be considered as a relevant non-destructive technique examination for the defect detection of DEMO divertor fingers.     

Does a regional accent perturb speech processing?

The processing costs involved in regional accent normalization were evaluated by measuring differences in lexical decision latencies for targets placed at the end of sentences with different French regional accents. Over a series of 6 experiments, the authors examined the time course of comprehension disruption by manipulating the duration and presentation conditions of accented speech. Taken together, the findings of these experiments indicate that regional accent normalization involves a short-term adjustment mechanism that develops as a certain amount of accented signal is available, resulting in a temporary perturbation in speech processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Growth of one-dimensional Si/SiGe heterostructures by thermal CVD

The first results on a simple new process for the direct fabrication of one-dimensional superlattices using common CVD chambers are presented. The experiments were carried out in a 200?mm industrial Centura reactor (Applied Materials). Low dimensionality and superlattices allow a significant increase in the figure of merit of thermoelectrics by controlling the transport of phonons and electrons. The monocrystalline nanowires produced according to this process are both one-dimensional and present heterostructures, with very thin layers (40?nm) of Si and SiGe. Concentrations up to 30?at.% Ge were obtained in the SiGe parts. Complementary techniques including transmission electronic microscopy (TEM), selected area electron diffraction (SAED), energy dispersive x-ray spectroscopy (EDS), scanning transmission electron microscopy (STEM) in bright field and high angle annular dark field (HAADF STEM), and energy-filtered transmission electron microscopy (EF-TEM) were used to characterize the nanoheterostructures.     

A 1D High Performance Thin Layer Chromatography Method Validated to Quantify Phospholipids Including Cardiolipin and Monolysocardiolipin from Biological Samples

The aim of this study is to identify high performance thin layer chromatography (HPTLC) conditions allowing the separation and quantification of mammalian cellular phospholipids (PLs) (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, and especially phosphatidic acid, cardiolipin, and monolysocardiolipin, these latter two being specifically located in mitochondria membranes). In order to make this method faster and easier, a 1D HPTLC method is chosen, testing several eluents as well as several staining methods. A pre‐conditioning of HPTLC plates with boric acid and a copper staining reagent followed by carbonization are selected for the quality of PL separation and homogeneity of staining. The selected conditions are discussed and the method validation is performed according to the International Conference on Harmonization guidelines. Linearity is effective between 1 and 8 µg and limit of quantification is between 0.5 and 2.3 µg depending on PL classes. Precision measurements show coefficients of variation <6%, and when amounts are close to the detection limit, <12%. Lipid extracts of tumor cell lines or isolated mitochondria are used to assess PL profiles. This shows that the HPTLC method can be used routinely to follow level variations of PLs. Practical Applications: The changes in PL composition play a crucial role in tumor processes and regulate cellular functions modulating cellular signaling or mitochondrial metabolism. The simple and cost‐effective 1D HPTLC method that is developed is applied to lipid extracts of whole tumor cells or hepatocyte‐isolated mitochondria. It is sensitive as well as precise to detect variations of phosphatidic acid or cardiolipin levels linked to physio‐pathological conditions. It can also be used to investigate the composition changes of other membrane PLs. Moreover, with a simultaneous analysis of 14 samples/standards on the same plate (six plates per day), this method is adapted for large series of samples.