Cross-sectional analysis of cortical thickness across the lifespan

An understanding of the normal aging process across the lifespan is important for gaining an understanding the pathophysiological changes that occur in accelerated aging diseases, such as Alzheimer’s Disease Dementia (ADD) and Vascular Dementia (VaD). The present study cross-sectionally analyzed cortical thickness values derived from T1-weighted magnetic resonance images for two large cohorts: Human Connectome Project and the Mayo Clinic Study of Aging. The 897 participants aged between 22-36 from the Human Connectome Project and the 801 participants aged between 52-92 from the Mayo Clinic Study of Aging created a robust cohort of non-demented individuals across the lifespan. We found age effects in four out of five composite regions of interest (Sensorimotor Cortex, Parietal Lobe, Frontal Lobe, and Cingulate Gyrus) between both cohorts. As expected, the age effects were more significant in older individuals from the Mayo Clinic Study of Aging. There were additionally sex effects within the Mayo Clinic Study of Aging cohort, but not in the Human Connectome Project. By showing significant sex effects within older individuals but not in younger individuals, there is likely a point beyond age 36 in which there exists a transitional period that sparks future sex-specific decline

Hypophosphatemic rickets: Revealing Novel Control Points for Phosphate Homeostasis

Rapid and somewhat surprising advances have recently been made towards understanding the molecular mechanisms causing heritable disorders of hypophosphatemia. The results of clinical, genetic, and translational studies have interwoven novel concepts underlying the endocrine control of phosphate metabolism, with far-reaching implications for treatment of both rare, Mendelian diseases as well as common disorders of blood phosphate excess such as chronic kidney disease (CKD). In particular, diseases caused by changes in the expression and proteolytic control of the phosphaturic hormone Fibroblast growth factor-23 (FGF23) have come to the forefront in terms of directing new models explaining mineral metabolism. These hypophosphatemic disorders, as well as others resulting from independent defects in phosphate transport or metabolism, will be reviewed herein, and implications for emerging therapeutic strategies based upon these new findings will be discussed

Equivalent circuit modeling to design a dual-band dual linear-to-circular polarizer surface

The working principle of a thin dual-band dual-linear to circular polarizer is presented here. This polarizer not only converts incident linearly polarized (LP) waves to circularly polarized (CP) waves in two frequency bands, but it also reverses the handedness of each signal. The electromagnetic behavior of the cell is carefully analyzed and two equivalent circuit models (ECMs) are presented to model the responses of the cell to linearly polarized waves at normal incidence. The ECMs show how utilizing interlayer coupling can be leveraged to achieve reversed CP senses in two bands using a compact design. Analytical formulas are presented to provide initial values of the ECM components including the mutual coupling inductances. We present measurement results that agree well with the full-wave simulation and the ECM results, thus validating the proposed ECM model.info:eu-repo/semantics/acceptedVersio

Emergence of Epizootic Ulcerative Syndrome in Native Fish of the Murray-Darling River System, Australia: Hosts, Distribution and Possible Vectors

Epizootic ulcerative syndrome (EUS) is a fish disease of international significance and reportable to the Office International des Epizootics. In June 2010, bony herring Nematalosa erebi, golden perch Macquaria ambigua, Murray cod Maccullochella peelii and spangled perch Leiopotherapon unicolor with severe ulcers were sampled from the Murray-Darling River System (MDRS) between Bourke and Brewarrina, New South Wales Australia. Histopathology and polymerase chain reaction identified the fungus-like oomycete Aphanomyces invadans, the causative agent of EUS. Apart from one previous record in N. erebi, EUS has been recorded in the wild only from coastal drainages in Australia. This study is the first published account of A. invadans in the wild fish populations of the MDRS, and is the first confirmed record of EUS in M. ambigua, M. peelii and L. unicolor. Ulcerated carp Cyprinus carpio collected at the time of the same epizootic were not found to be infected by EUS, supporting previous accounts of resistance against the disease by this species. The lack of previous clinical evidence, the large number of new hosts (n = 3), the geographic extent (200 km) of this epizootic, the severity of ulceration and apparent high pathogenicity suggest a relatively recent invasion by A. invadans. The epizootic and associated environmental factors are documented and discussed within the context of possible vectors for its entry into the MDRS and recommendations regarding continued surveillance, research and biosecurity are made

Probing spectral properties of radio-quiet quasars searched for optical microvariability-II

In the context of AGN unification scheme rapid variability properties play an important role in understanding any intrinsic differences between sources in different classes. In this respect any clue based on spectral properties will be very useful toward understanding the mechanisms responsible for the origin of rapid small scale optical variations, or microvariability. Here we have added spectra of 46 radio-quiet quasars (RQQSOs) and Seyfert 1 galaxies to those of our previous sample of 37 such objects, all of which had been previously searched for microvariability. We took new optical spectra of 33 objects and obtained 13 others from the literature. Their \hbeta and \mgii emission lines were carefully fit to determine line widths (FWHM) as well as equivalent widths (EW) due to the broad emission line components. The line widths were used to estimate black hole masses and Eddington ratios, $\ell$. Both EW and FWHM are anticorrelated with $\ell$. Nearly all trends were in agreement with our previous work, although the tendency for sources exhibiting microvariability to be of lower luminosity was not confirmed. Most importantly, this whole sample of EW distributions provides no evidence for the hypothesis that a weak jet component in the radio quiet AGNs is responsible for their microvariability.Comment: 15 pages, 9 figures, 6 tables, Accepted in MNRAS main journa