Epitaxial films of NdFeAsO were grown on GaAs substrates by molecular beam epitaxy (MBE). All elements including oxygen were supplied from solid sources using Knudsen cells. The x-ray diffraction pattern of the film prepared with the optimum growth condition showed no indication of impurity phases. Only (00l) peaks were observed, indicating that NdFeAsO was grown with the c-axis perpendicular to the substrate. The window of optimum growth condition was very narrow, but the NdFeAsO phase was grown with a very good reproducibility. Despite the absence of any appreciable secondary phase, the resistivity showed an increase with decreasing temperature

Single-molecule pH sensors have been developed by utilizing molecular imaging of pH-responsive shape transition of nanomechanical DNA origami devices with atomic force microscopy (AFM). Short DNA fragments that can form i-motifs were introduced to nanomechanical DNA origami devices with pliers-like shape (DNA Origami Pliers), which consist of two levers of 170-nm long and 20-nm wide connected at a Holliday-junction fulcrum. DNA Origami Pliers can be observed as in three distinct forms; cross, antiparallel and parallel forms, and cross form is the dominant species when no additional interaction is introduced to DNA Origami Pliers. Introduction of nine pairs of 12-mer sequence (5′-AACCCCAACCCC-3′), which dimerize into i-motif quadruplexes upon protonation of cytosine, drives transition of DNA Origami Pliers from open cross form into closed parallel form under acidic conditions. Such pH-dependent transition was clearly imaged on mica in molecular resolution by AFM, showing potential application of the system to single-molecular pH sensors.

Snake venoms are natural sources of biologically active molecules that are able to act selectively and specifically on different cellular targets, modulating physiological functions. Thus, these mixtures, composed mainly of proteins and peptides, provide ample and challenging opportunities and a diversified molecular architecture to design and develop tools and agents of scientific and therapeutic interest. Among these components, peptides and small proteins play diverse roles in numerous physiological processes, exerting a wide range of pharmacological activities, such as antimicrobial, antihypertensive, analgesic, antitumor, analgesic, among others. The pharmaceutical and cosmetic industries have recognized the huge potential of these privileged frameworks and believe them to be a promising alternative to contemporary drugs. A number of natural or synthetic peptides from snake venoms have already found preclinical or clinical applications for the treatment of pain, hypertension, cardiovascular diseases and aging skin. A well-known example is captopril, whose natural peptide precursor was isolated from Bothrops jararaca snake venom, which is a peptide-based drug that inhibits the angiotensin-converting enzyme, producing an anti-hypertensive effect. The present review looks at the main peptides (natriuretic peptides, bradykinin-potentiating peptides and sarafotoxins) and low mass proteins (crotamine, disintegrins and three-Finger toxins) from snake venoms, as well as synthetic peptides inspired by them, describing their biochemical, structural and physiological features, as well as their applications as research tools and therapeutic agents.

Koba S, Watanabe R, Kano N, Watanabe T. Oxidative stress exaggerates skeletal muscle contraction-evoked reflex sympathoexcitation in rats with hypertension induced by angiotensin II. Am J Physiol Heart Circ Physiol 304: H142-H153, 2013. First published October 19, 2012 doi:10.1152/ajpheart.00423.2012.-Muscle contraction stimulates thin fiber muscle afferents and evokes reflex sympathoexcitation. In hypertension, this reflex is exaggerated. ANG II, which is elevated in hypertension, has been reported to trigger the production of superoxide and other reactive oxygen species. In the present study, we tested the hypothesis that increased ANG II in hypertension exaggerates skeletal muscle contraction-evoked reflex sympathoexcitation by inducing oxidative stress in the muscle. In rats, subcutaneous infusion of ANG II at 450 ng·kg Ϫ1 ·min Ϫ1 for 14 days significantly (P Ͻ 0.05) elevated blood pressure compared with shamoperated (sham) rats. Electrically induced 30-s hindlimb muscle contraction in decerebrate rats with hypertension evoked larger renal sympathoexcitatory and pressor responses [ϩ1,173 Ϯ 212 arbitrary units (AU) and ϩ35 Ϯ 5 mmHg, n ϭ 10] compared with sham normotensive rats (ϩ419 Ϯ 103 AU and ϩ13 Ϯ 2 mmHg, n ϭ 11). Tempol, a SOD mimetic, injected intra-arterially into the hindlimb circulation significantly reduced responses in hypertensive rats, whereas this compound had no effect on responses in sham rats. Tiron, another SOD mimetic, also significantly reduced reflex renal sympathetic and pressor responses in a subset of hypertensive rats (n ϭ 10). Generation of muscle superoxide, as evaluated by dihydroethidium staining, was increased in hypertensive rats. RT-PCR and immunoblot experiments showed that mRNA and protein for gp91 phox , a NADPH oxidase subunit, in skeletal muscle tissue were upregulated in hypertensive rats. Taken together, hese results suggest that increased ANG II in hypertension induces oxidative stress in skeletal muscle, thereby exaggerating the muscle reflex. muscle contraction; angiotensin II; oxidative stress; sympathetic nerve activity HYPERTENSION is associated with an increased risk of cardiovascular disease (50). Antihypertensive treatments include increased physical activity or exercise (8, 23). It has been noted that in hypertension, the sympathoexcitation and elevation of blood pressure seen during exercise are excessive (10,39). This cardiovascular hyperexcitability is potentially dangerous because it can elevate risks for adverse cardiac events such as acute myocardial ischemia, myocardial infarction, left ventricular hypertrophy, or arrhythmia as well as stroke after a bout of exercise (23,36). Determining the causes underlying the hyperexcitability in this pathological condition is clinically important.A reflex originating in exercising skeletal muscle is activated as thin fiber muscle afferents (groups III and IV) are stimulated by mechanical deformation of the afferents' receptive fields as well as by metabolic byproducts during contraction (9, 33). In turn, afferent e...

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Background: The purpose of this study was to find a utility of a newly developed 3D-printed sinus model and to evaluate the educational benefit of simulation training with the models for functional endoscopic sinus surgery (FESS).Material and methods: Forty-seven otolaryngologists were categorized as experts (board-certified physicians with ≥200 experiences of FESS, n = 9), intermediates (board-certified physicians with <200 experiences of FESS, n = 19), and novices (registrars, n = 19). They performed FESS simulation training on 3D-printed models manufactured from DICOM images of computed tomography (CT) scan of real patients. Their surgical performance was assessed with the objective structured assessment of technical skills (OSATS) score and dissection quality evaluated radiologically with a postdissection CT scan. First we evaluated the face, content, and constructive values. Second we evaluated the educational benefit of the training. Ten novices underwent training (training group) and their outcomes were compared to the remaining novices without training (control group). The training group performed cadaveric FESS surgeries before and after the repetitive training.Results: The feedback from experts revealed high face and content value of the 3Dprinted models. Experts, intermediates, and novices demonstrated statistical differ-

In this paper, we report on a parallel freeviewpoint video synthesis algorithm that can efficiently reconstruct a high-quality 3D scene representation of sports scenes. The proposed method focuses on a scene that is captured by multiple synchronized cameras featuring wide-baselines. The following strategies are introduced to accelerate the production of a free-viewpoint video taking the improvement of visual quality into account: (1) a sparse point cloud is reconstructed using a volumetric visual hull approach, and an exact 3D ROI is found for each object using an efficient connected components labeling algorithm. Next, the reconstruction of a dense point cloud is accelerated by implementing visual hull only in the ROIs; (2) an accurate polyhedral surface mesh is built by estimating the exact intersections between grid cells and the visual hull; (3) the appearance of the reconstructed presentation is reproduced in a view-dependent manner that respectively renders the non-occluded and occluded region with the nearest camera and its neighboring cameras. The production for volleyball and judo sequences demonstrates the effectiveness of our method in terms of both execution time and visual quality.

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