21,026 research outputs found

    Inhibitory control as a mediator of bidirectional effects between early oppositional behavior and maternal depression.

    Get PDF
    Maternal depression is an established risk factor for child conduct problems, but relatively few studies have tested whether children's behavioral problems exacerbate mothers' depression or whether other child behavioral characteristics (e.g., self-regulation) may mediate bidirectional effects between maternal depression and child disruptive behavior. This longitudinal study examined the parallel growth of maternal depressive symptoms and child oppositional behavior from ages 2 to 5; the magnitude and timing of their bidirectional effects; and whether child inhibitory control, a temperament-based self-regulatory mechanism, mediated effects between maternal depression and child oppositionality. A randomized control trial of 731 at-risk families assessed children annually from ages 2 to 5. Transactional models demonstrated positive and bidirectional associations between mothers' depressive symptoms and children's oppositional behavior from ages 2 to 3, with a less consistent pattern of reciprocal relations up to age 5. Mediation of indirect mother-child effects and child evocative effects depended on the rater of children's inhibitory control. Findings are discussed in regard to how child evocative effects and self-regulatory mechanisms may clarify the transmission of psychopathology within families

    Wildflowers and Ferns of Kentucky

    Get PDF
    Since Kentucky is situated at a biological crossroads in eastern North America, citizens and visitors to this beautiful state are likely to be greeted by an astonishing variety of wildflowers. This non-technical guide—featuring more than five hundred dazzling full-color photographs by award-winning photographer Thomas G. Barnes—is the state’s indispensable guide to the most common species in the Commonwealth. With this book, readers will learn to identify and appreciate Kentucky wildflowers and ferns by matching photographs and leaf line drawings to the more than six hundred and fifty species of flowers covered in the book. Extremely practical and simple to use, the guide’s color photographs and line drawings appear with plant descriptions for easy identification, and plants are grouped by flower color and blooming season. Each species listing includes the plant’s common and scientific name, plant family, habitat, frequency, and distribution throughout Kentucky, with similar species listed in the notes. There is no other volume that covers the flora of Kentucky with such ease of identification. The first new statewide guide to appear in thirty years, with its combination of high quality photographs, illustrations, portability, and easy organization of information, Wildflowers and Ferns of Kentucky is an essential addition to the library or field pack of the wildflower enthusiast, naturalist, and anyone else who loves the outdoors. Thomas G. Barnes, an extension professor of forestry and wildlife specialist in the Department of Forestry, College of Agriculture at the University of Kentucky, is the author of Kentucky’s Last Great Places. Former naturalist S. Wilson Francis, Ph.D., is park superintendent at Natural Bridge State Resort Park in Kentucky. An essential addition to the library or field pack of the wildflower enthusiast or naturalist. —Kentucky Alumni A striking volume, memorable not only for its color photographs and plant descriptions but also for its introductory exposition of such pertinent matters as finding a good definition for \u27wildflower\u27 and one for \u27weed.\u27 —Mountain Eagle There isn\u27t a gardener on your gift list who wouldn\u27t be delighted by this book. Don\u27t forget-you need a copy too. —Southsider Wildflowers and Ferns of Kentucky is an extraordinarily beautiful, helpful, full color, 344-page guide showing 634 of the most common species of native ferns and seed-bearing wildflowers in Kentucky. —State Magazine Utilizes strong artistic compositions without compromising the identifiable characteristics of the plant. —Burpee Museum of Natural History This book is an excellent choice for professionals and general readers interested in the flora of Kentucky, adjacent states, and the northeastern US. . . . Highly recommended. —Choice Contains superb color photographs that make identifying the ferns and flowers much easier. —Modern Mountain Magazine A must-have for Kentuckiana gardeners. . . . A beautiful book that is easy to use (and carry) as a field guide. —Perry County News An astonishing variety of plant life exists in Kentucky\u27s diverse geography, and the book represents the impressive mix. . . . Even a botanical novice will benefit from perusing this delightfully blooming book. —Southern Livinghttps://uknowledge.uky.edu/upk_plant_sciences/1005/thumbnail.jp

    Sialic Acid Mutarotation Is Catalyzed by the Escherichia coli β-Propeller Protein YjhT

    Get PDF
    The acquisition of host-derived sialic acid is an important virulence factor for some bacterial pathogens, but in vivo this sugar acid is sequestered in sialoconjugates as the {alpha}-anomer. In solution, however, sialic acid is present mainly as the β-anomer, formed by a slow spontaneous mutarotation. We studied the Escherichia coli protein YjhT as a member of a family of uncharacterized proteins present in many sialic acid-utilizing pathogens. This protein is able to accelerate the equilibration of the {alpha}- and β-anomers of the sialic acid N-acetylneuraminic acid, thus describing a novel sialic acid mutarotase activity. The structure of this periplasmic protein, solved to 1.5Å resolution, reveals a dimeric 6-bladed unclosed β-propeller, the first of a bacterial Kelch domain protein. Mutagenesis of conserved residues in YjhT demonstrated an important role for Glu-209 and Arg-215 in mutarotase activity. We also present data suggesting that the ability to utilize {alpha}-N-acetylneuraminic acid released from complex sialoconjugates in vivo provides a physiological advantage to bacteria containing YjhT

    Sonography of Common Peripheral Nerve Disorders With Clinical Correlation

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135210/1/jum2016354683.pd

    Plasma Leptin Levels and Incidence of Heart Failure, Cardiovascular Disease, and Total Mortality in Elderly Individuals

    Get PDF
    OBJECTIVE: Obesity predisposes individuals to congestive heart failure (CHF) and cardiovascular disease (CVD). Leptin regulates energy homeostasis, is elevated in obesity, and influences ventricular and vascular remodeling. We tested the hypothesis that leptin levels are associated with greater risk of CHF, CVD, and mortality in elderly individuals. RESEARCH DESIGN AND METHODS: We evaluated 818 elderly (mean age 79 years, 62% women) Framingham Study participants attending a routine examination at which plasma leptin was assayed. RESULTS: Leptin levels were higher in women and strongly correlated with BMI (P < 0.0001). On follow-up (mean 8.0 years), 129 (of 775 free of CHF) participants developed CHF, 187 (of 532 free of CVD) experienced a first CVD event, and 391 individuals died. In multivariable Cox regression models adjusting for established risk factors, log-leptin was positively associated with incidence of CHF and CVD (hazard ratio [HR] per SD increment 1.26 [95% CI 1.03–1.55] and 1.28 [1.09–1.50], respectively). Additional adjustment for BMI nullified the association with CHF (0.97 [0.75–1.24]) but only modestly attenuated the relation to CVD incidence (1.23 [1.00–1.51], P = 0.052). We observed a nonlinear, U-shaped relation between log-leptin and mortality (P = 0.005 for quadratic term) with greater risk of death evident at both low and high leptin levels. CONCLUSIONS: In our moderate-sized community-based elderly sample, higher circulating leptin levels were associated with a greater risk of CHF and CVD, but leptin did not provide incremental prognostic information beyond BMI. Additional investigations are warranted to elucidate the U-shaped relation of leptin to mortality.National Institutes of Health's National Heart, Lung, and Blood Institute (N01-HC25195, N01-HV28178, K24-HL04334, R01-DK080739

    The VAST Survey - III. The multiplicity of A-type stars within 75 pc

    Full text link
    With a combination of adaptive optics imaging and a multi-epoch common proper motion search, we have conducted a large volume-limited (D \le 75 pc) multiplicity survey of A-type stars, sensitive to companions beyond 30 au. The sample for the Volume-limited A-STar (VAST) survey consists of 435 A-type stars: 363 stars were observed with adaptive optics, 228 stars were searched for wide common proper motion companions and 156 stars were measured with both techniques. The projected separation coverage of the VAST survey extends from 30 to 45,000 au. A total of 137 stellar companions were resolved, including 64 new detections from the VAST survey, and the companion star fraction, projected separation distribution and mass ratio distribution were measured. The separation distribution forms a log-normal distribution similar to the solar-type binary distribution, but with a peak shifted to a significantly wider value of 387 (+132,-98) au. Integrating the fit to the distribution over the 30 to 10,000 au observed range, the companion star fraction for A-type stars is estimated as 33.8%+-2.6%. The mass ratio distribution of closer (<125 au) binaries is distinct from that of wider systems, with a flat distribution for close systems and a distribution that tends towards smaller mass ratios for wider binaries. Combining this result with previous spectroscopic surveys of A-type stars gives an estimate of the total companion star fraction of 68.9%+-7.0%. The most complete assessment of higher order multiples was estimated from the 156-star subset of the VAST sample with both adaptive optics and common proper motion measurements, combined with a literature search for companions, yielding a lower limit on the frequency of single, binary, triple, quadruple and quintuple A-type star systems of 56.4 (-4.0,+3.8), 32.1 (-3.5,+3.9), 9.0 (-1.8,+2.8), 1.9 (-0.6,+1.8) and 0.6 (-0.2,+1.4) per cent, respectively.Comment: 46 pages, 24 figures. Accepted for publication in the Monthly Notices of the Royal Astronomical Society, 7th October 201

    The Outbursts and Orbit of the Accreting Pulsar GS 1843-02 = 2S 1845-024

    Get PDF
    We present observations of a series of 10 outbursts of pulsed hard X-ray flux from the transient 10.6 mHz accreting pulsar GS 1843-02, using the Burst and Transient Source Experiment on the Compton Gamma Ray Observatory. These outbursts occurred regularly every 242 days, coincident with the ephemeris of the periodic transient GRO J1849-03 (Zhang et al. 1996), which has recently been identified with the SAS 3 source 2S 1845-024 (Soffitta et al. 1998). Our pulsed detection provides the first clear identification of GS 1843-02 with 2S 1845-024. We present a pulse timing analysis which shows that the 2S 1845-024 outbursts occur near the periastron passage of the neutron star's highly eccentric (e = 0.88+-0.01) 242.18+-0.01 day period binary orbit about a high mass (M > 7 solar masses) companion. The orbit and transient outburst pattern strongly suggest the pulsar is in a binary system with a Be star. Our observations show a long-term spin-up trend, with most of the spin-up occurring during the outbursts. From the measured spin-up rates and inferred luminosities we conclude that an accretion disk is present during the outbursts.Comment: Accepted for publication in Astrophysical Journa
    corecore