5,892 research outputs found
Isolation and characterisation of a pax group III gene from the freshwater crayfish cherax destructor: Implications for the evolution of muscle regeneration
Pax genes encode transcription factors that are highly evolutionarily conserved and are vital for animal development. Vertebrate Pax group III genes Pax3 and Pax7 are required for proper development of muscular and central nervous systems. In their roles in muscular systems, Pax3 and Pax7 specify myoblasts (muscle progenitor cells). Pax3 is predominantly involved in embryonic myogenesis and specifies embryonic myoblasts. In contrast, Pax7 specifies adult myoblasts (muscle satellite cells), and has been demonstrated to be vital for adult muscle regeneration. Recent evidence also implicates a role for Pax7 in the conversion of certain stem cells to the myogenic lineage. The Australian freshwater crayfish Cherax destructor (yabby) possesses a phenomenal capability for almost limitless adult muscle regeneration. Interestingly, C. destructor undergoes two distinct types of adult muscle regeneration, and these appear to be driven by two distinct types of muscle progenitor/stem cell. C. destructor has a highly regulated system for normal muscle growth, which is strictly regulated around the periodic shedding of the growth-restricting exoskeleton. The muscle regeneration that occurs in this normal growth is driven predominantly by endogenous muscle satellite cells. C. destructor also possesses the fascinating ability to regenerate entire limbs, including all of the muscle contained within them. This process appears to utilise circulating haematopoietic stem cells as the dominant muscle progenitor cell (myoblast). The role for Pax7 in adult muscle regeneration in vertebrates indicates that Pax group III genes may be appropriate candidates to study in muscle regeneration in C. destructor. Pax group III genes have been isolated in fruit fly, grasshopper, mite and jellyfish, and have not been demonstrated to be expressed during embryonic or adult myogenesis in any of these animals. Prior to this research, Pax genes had not been isolated from Crustacea. I have designed nested partially-degenerate primers to complement conserved regions of known arthropod Pax group III gene sequences, and used PCR and RT-PCR of C.
destructor genomic DNA and embryonic RNA, respectively. Sequencing of reaction products confirmed the presence of a Pax group III gene in Crustacea. In this research I have isolated a single Pax group III gene from C. destructor which I have designated Cdpax3/7. Cdpax3/7 is unequivocally a Pax group III gene, and appears to be the only Pax group III gene present in C. destructor. Cdpax3/7 contains two DNA binding domains characteristic of Pax group III proteins, the paired domain and the homeodomain. Cdpax3/7 also contains an octapeptide motif characteristic of the majority of Pax group III proteins. Interestingly, Cdpax317 is expressed as two alternate transcripts. One alternate transcript lacks a 93 nucleotide section corresponding to approximately one third of the paired domain, indicating that it may have altered DNA binding, and therefore function. RT-PCR expression assays indicate that Cdpax3/7 is expressed embryonically (in whole C. destructor embryos), in normal non-regenerating adult muscle, in adult muscle undergoing normal regeneration, as well as in limb regeneration (both before and after myogenic differentiation). The gross expression pattern of Cdpax3/7 in adult muscle regeneration is characteristic of the expression patterns of vertebrate Pax7 in the analogous vertebrate process
The Virtual photon-gluon impact factor with massive quarks and exact gluon kinematics.
e calculate the impact factor coupling a virtual photon to a gluon via a massive quark-antiquark
pair at LL order, but with the imposition of the correct gluon kinematics. Exact analytical results are
presented in triple Mellin space with respect to scaled Bjorken x, gluon transverse momentum and heavy
quark mass. The application of these results to the calculation of approximate NLL coefficient functions
needed to relate structure functions to the BFKL gluon is presented. The NLL effects with running
coupling are seen to lead to a suppression of the small x divergence when compared with the fixed and
running coupling LL results, but less than in the massless case
Nursing behaviour as a predictor of alternate-year reproduction in muskoxen
Our finding significant differences in nursing behavior during the post-rut period supports the hypothesis that female muskoxen use factors other than their nutritional condition to determine their reproductive strategy
EC71-1528 Cattle Grub Control in Nebraska
Extension Circular 71-1528 is about cattle grubs. Cattle grubs are immature or larval stages of warble flies
Determinants of Hotel Property Prices
Pricing commercial real estate has its foundations in present value theory. Recent improvements for accessing transaction data have stimulated interest in commercial property hedonic pricing models, the structures of which follow traditions in single-family real estate in that the implicit prices of property characteristics and site-specific variables represent city and national market conditions. Adding present value variables has become increasingly common to account for general market conditions. We test two hedonic pricing models; one that follows the residential tradition and another that departs by incorporating city-specific net operating incomes and the discount rates. Modeling prices in these alternative ways allows for recognition of the relative contributions of property, city, and capital market determinants. Empirical testing relies on a sample of hotel transactions from 2005–2010. The responsiveness of hotel cash flows to market changes is an important consideration. We find that models with property characteristics perform about the same as models that also include present value variables. A plausible explanation for this phenomenon is that implicit prices corresponding to property characteristics and site-specific variables appear to reflect income streams associated with city and nationwide economic conditions
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Integrated safety studies of the urate reabsorption inhibitor lesinurad in treatment of gout.
ObjectiveLesinurad (LESU) is a selective urate reabsorption inhibitor approved at 200 mg daily for use with a xanthine oxidase inhibitor (XOI) to treat hyperuricaemia in gout patients failing to achieve target serum urate on XOI. The aim of the study was to investigate the long-term safety of LESU + XOI therapy.MethodsSafety data were pooled from three 12-month phase III (core) trials evaluating LESU 200 and 400 mg/day combined with an XOI (LESU200+XOI and LESU400+XOI), and two 12-month extension studies using descriptive statistics. To adjust for treatment duration, treatment-emergent adverse events (TEAEs) were expressed as exposure-adjusted incidence rates (patients with events per 100 person-years).ResultsIn the core studies, exposure-adjusted incidence rates for total and total renal-related TEAEs were comparable for XOI alone and LESU200+XOI but higher with LESU400+XOI. Exposure-adjusted incidence rates for serum creatinine (sCr) elevations â©ľ1.5Ă—baseline were 2.9, 7.3 and 18.7, respectively. Resolution (sCr â©˝1.2Ă—baseline) occurred in 75-90% of all events, with 66-75% occurring without any study medication interruption. Major adverse cardiovascular events were 3, 4 and 9 with XOI, LESU200+XOI and LESU400+XOI, respectively. Longer exposure in core+extension studies did not increase rates for any safety signals.ConclusionAt the approved dose of 200 mg once-daily combined with an XOI, LESU did not increase renal, cardiovascular or other adverse events compared with XOI alone, except for sCr elevations. With extended exposure in the core+extension studies, the safety profile was consistent with that observed in the core studies, and no new safety concerns were identified
The Dress of Words : Essays on Restoration and Eighteenth Century Literature in Honor of Richmond P. Bond
vii, 220 p. ; 25 c
Determinants of Hotel Property Prices
Commercial real estate pricing has its foundations in present value theory although improved access to transaction data heightened interest in hedonic pricing models. Heretofore, the commercial property versions of these models follow traditions for pricing non-market rent paying durable assets, principally residential housing. We present a pricing model that departs from tradition by incorporating city-specific net operating incomes and the capitalization rates into the hedonic equation. Property attributes and location characteristics serve as proxies for unobservable, asset cash flows; city incomes account for local cash flow effects; and the capitalization rate represent local and national capital market influences. Modeling commercial real estate in this way allows us to recognize the relative contributions of property, local market, and national market determinants. Empirical testing relies on a sample of hotel transactions from 2005-2010. The choice of hotels stems from the responsiveness of these properties’ cash flows to market changes in the absence of lease friction and the homogeneity of the physical assets. Our model explains nearly 80 percent of the variation in hotel asset prices. We find that prices are collectively determined by property, city income, and capital market characteristics. Models only with property characteristics slightly outperform models with present value variables
Methods of Higher Alcohol Synthesis
Systems, catalysts, and methods are provided for transforming carbon based material into synthetic mixed alcohol fuel
Connecting Clump Sizes in Turbulent Disk Galaxies to Instability Theory
In this letter we study the mean sizes of Halpha clumps in turbulent disk
galaxies relative to kinematics, gas fractions, and Toomre Q. We use 100~pc
resolution HST images, IFU kinematics, and gas fractions of a sample of rare,
nearby turbulent disks with properties closely matched to z~1.5-2 main-sequence
galaxies (the DYNAMO sample). We find linear correlations of normalized mean
clump sizes with both the gas fraction and the velocity dispersion-to-rotation
velocity ratio of the host galaxy. We show that these correlations are
consistent with predictions derived from a model of instabilities in a
self-gravitating disk (the so-called "violent disk instability model"). We also
observe, using a two-fluid model for Q, a correlation between the size of
clumps and self-gravity driven unstable regions. These results are most
consistent with the hypothesis that massive star forming clumps in turbulent
disks are the result of instabilities in self-gravitating gas-rich disks, and
therefore provide a direct connection between resolved clump sizes and this in
situ mechanism.Comment: Accepted to Apj Letter
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