561 research outputs found
Sea turtle nesting activity along Eglin Air Force Base on Cape San Blas and Santa Rosa Island, Florida from 1994 to 1997.
Along EAFB on Cape San BIas, the only sea turtle species nest observed has been
the loggerhead turtle. The first green turtle nest documented along the Florida panhandle
coast was observed on EAFB property, however (D. Atencio, EAFB, pers. comm). Santa
Rosa Island, located approximately 150 miles west of Cape San BIas supports a small but
consistent, group of nesting green turtles (Fig. 2). Although erosion is not as severe along
Santa Rosa Island as it is on Cape San BIas, and vehicular traffic is not permitted, sea
turtles nesting on this barrier island must survive severe tropical storms, predation, and
artificial lighting to be successful. Because this area supports a rare group of nesting green
turtles and is disturbed by intense artificial lighting from Air Force missions and adjacent
resort towns, continued monitoring is necessary. The sea turtle species that nest along this
barrier island, and the human activities that disturb those sea turtles present unique
circumstances for management ofthis area. Protection ofthe significant nesting
populations of sea turtles on EAFB properties on Cape San BIas and Santa Rosa Island
requires yearly monitoring of the nesting activity and the natural and human disturbances
influencing the nesting females.
The objectives ofthis study were to monitor sea turtle nesting along EAFB on
Cape San BIas to determine number of nests and hatching success, assess disturbances,
and determine proper management to ensure successful nesting and hatching.(56 page document
The Cape San Blas Ecological Study
Eglin AFB on Cape San Blas consists of approximately 250 acres located about
180 miles east of the main Eglin reservation. This area lies on the S1. Joseph peninsula,
part of a dynamic barrier island chain that extends across the northern Gulf of Mexico.
Due to the natural forces that formed Cape San Blas and those that maintain this area, St.
Joseph Peninsula has experienced severe land form change over time (see GIS land form
change maps). These changes allow for fluctuations in habitat types along Cape San Blas
(see GIS land cover change maps)that influence the floral and faunal species using this
area.
The dynamic environment along Cape San Blasincludes flatwoods, interdunal
swale, rosemary scrub, and beachfront. These habitats support a wide array of species,
including several threatened and endangered species such as the loggerhead sea turtle
(Caretta caretta), PipingPlover (Charadnus melodus), Least Tern (Sterna antillarum),
and Bald Eagle (Haliaeetus leucocephalus). Proper management of these species and their
habitats require knowledge of their abundance and distribution, and the effects
disturbances have on their survival.
In addition to threatened and endangered flora and fauna, Cape San Blas also
supports tourists and recreationists. Although Gulf County is sparsely populated, with
approximately 13,000 inhabitants throughout 578 square miles, summer tourism and heavy
recreational use of beaches for fishing, crabbing, and shelling place continued and
increasing pressure on the natural resources of these areas (Rupert 1991). Gulf County is
also one of the few remaining counties in Florida that permits vehicular traffic on its
beaches, including Cape San Blas. In addition to recreational use of these habitats;EAFB
also uses the area for military missions. Air Force property on Cape San Blas is primarily
used for radar tracking of flying missions over the Gulf of Mexico, although in recent
years it has been used for missile launchings and other various military activities.
To allow continued military and public use of Air Force property while also
protecting the unique flora and fauna of the area,EAFB proposed a characterization of the
resources found along Cape San Blas. A complete inventory of the physical features of the
area included investigating topography, soil chemistry, hydrology, archeology, and the
dynamics of land mass and land cover change over time. Various thematic layers within a
geographic information system (GIS) were used to spatially portray georeferenced data.
Large scale changes over time were assessed using stereo aerial photography. Vegetation
transects, soil samples, elevation transects, an archeological survey, freshwater wells, and
a tidal monitor were used to investigate the remaining features. (247 page document
Chemical regulators of epithelial plasticity reveal a nuclear receptor pathway controlling myofibroblast differentiation
Plasticity in epithelial tissues relates to processes of embryonic development, tissue fibrosis and cancer progression. Pharmacological modulation of epithelial transitions during disease progression may thus be clinically useful. Using human keratinocytes and a robotic high-content imaging platform, we screened for chemical compounds that reverse transforming growth factor β (TGF-β)-induced epithelial-mesenchymal transition. In addition to TGF-β receptor kinase inhibitors, we identified small molecule epithelial plasticity modulators including a naturally occurring hydroxysterol agonist of the liver X receptors (LXRs), members of the nuclear receptor transcription factor family. Endogenous and synthetic LXR agonists tested in diverse cell models blocked α-smooth muscle actin expression, myofibroblast differentiation and function. Agonist-dependent LXR activity or LXR overexpression in the absence of ligand counteracted TGF-β-mediated myofibroblast terminal differentiation and collagen contraction. The protective effect of LXR agonists against TGF-β-induced pro-fibrotic activity raises the possibility that anti-lipidogenic therapy may be relevant in fibrotic disorders and advanced cancer
Wnt3a Induces Myofibroblast Differentiation by Upregulating TGF-β Signaling Through SMAD2 in a β-Catenin-Dependent Manner
Growing evidence suggests the Wnt family of secreted glycoproteins and their associated signaling pathways, linked to development, are recapitulated during wound repair and regeneration events. However, the role of the Wnt pathway in such settings remains unclear. In the current study, we treated mouse fibroblasts with 250 ng/mL of recombinant Wnt3a for 72 hours and examined its affect on cell morphology and function. Wnt3a induced a spindle-like morphology in fibroblasts characterized by the increased formation of stress fibres. Wnt3a decreased the proliferation of fibroblasts, but significantly increased cell migration as well as fibroblast-mediated contraction of a collagen lattice. Wnt3a significantly increased the expression of TGF-β and its associated signaling through SMAD2. Consistent with this, we observed significantly increased smooth muscle α-actin expression and incorporation of this contractile protein into stress fibres following Wnt3a treatment. Knockdown of β-catenin using siRNA reversed the Wnt3a-induced smooth muscle α-actin expression, suggesting these changes were dependent on canonical Wnt signaling through β-catenin. Neutralization of TGF-β with a blocking antibody significantly inhibited the Wnt3a-induced smooth muscle α-actin expression, indicating these changes were dependent on the increased TGF-β signaling. Collectively, this data strongly suggests Wnt3a promotes the formation of a myofibroblast-like phenotype in cultured fibroblasts, in part, by upregulating TGF-β signaling through SMAD2 in a β-catenin-dependent mechanism. As myofibroblasts are critical regulators of wound healing responses, these findings may have important implications for our understanding of normal and aberrant injury and repair events
Double-resonant fast particle-wave interaction
In future fusion devices fast particles must be well confined in order to
transfer their energy to the background plasma. Magnetohydrodynamic
instabilities like Toroidal Alfv\'en Eigenmodes or core-localized modes such as
Beta Induced Alfv\'en Eigenmodes and Reversed Shear Alfv\'en Eigenmodes, both
driven by fast particles, can lead to significant losses. This is observed in
many ASDEX Upgrade discharges. The present study applies the drift-kinetic
HAGIS code with the aim of understanding the underlying resonance mechanisms,
especially in the presence of multiple modes with different frequencies. Of
particular interest is the resonant interaction of particles simultaneously
with two different modes, referred to as 'double-resonance'. Various mode
overlapping scenarios with different q profiles are considered. It is found
that, depending on the radial mode distance, double-resonance is able to
enhance growth rates as well as mode amplitudes significantly. Surprisingly, no
radial mode overlap is necessary for this effect. Quite the contrary is found:
small radial mode distances can lead to strong nonlinear mode stabilization of
a linearly dominant mode.Comment: 12 pages, 11 figures; Nuclear Fusion 52 (2012
Genetic parameters of ovarian and uterine reproductive traits in dairy cows
peer-reviewedThe objective of the study was to estimate genetic parameters of detailed reproductive traits derived from ultrasound examination of the reproductive tract as well as their genetic correlations with traditional reproductive traits. A total of 226,141 calving and insemination records as well as 74,134 ultrasound records from Irish dairy cows were used. Traditional reproductive traits included postpartum interval to first service, conception, and next calving, as well as the interval from first to last service; number of inseminations, pregnancy rate to first service, pregnant within 42 d of the herd breeding season, and submission in the first 21 d of the herd breeding season were also available. Detailed reproductive traits included resumed cyclicity at the time of ultrasound examination, incidence of multiple ovulations, incidence of early postpartum ovulation, heat detection, ovarian cystic structures, embryo loss, and uterine score; the latter was a subjectively assessed on a scale of 1 (little fluid with normal uterine tone) to 4 (large quantity of fluid with a flaccid uterine tone). Variance (and covariance) components were estimated using repeatability animal linear mixed models. Heritability for all reproductive traits were generally low (0.001–0.05), with the exception of traits related to cyclicity postpartum, regardless if defined traditionally (0.07; calving to first service) or from ultrasound examination [resumed cyclicity at the time of examination (0.07) or early postpartum ovulation (0.10)]. The genetic correlations among the detailed reproductive traits were generally favorable. The exception was the genetic correlation (0.29) between resumed cyclicity and uterine score; superior genetic merit for cyclicity postpartum was associated with inferior uterine score. Superior genetic merit for most traditional reproductive traits was associated with superior genetic merit for resumed cyclicity (genetic correlations ranged from −0.59 to −0.36 and from 0.56 to 0.70) and uterine score (genetic correlations ranged from −0.47 to 0.32 and from 0.25 to 0.52). Genetic predisposition to an increased incidence of embryo loss was associated with both an inferior uterine score (0.24) and inferior genetic merit for traditional reproductive traits (genetic correlations ranged from −0.52 to −0.42 and from 0.33 to 0.80). The results from the present study indicate that selection based on traditional reproductive traits, such as calving interval or days open, resulted in improved genetic merit of all the detailed reproductive traits evaluated in this study. Additionally, greater accuracy of selection for calving interval is expected for a relatively small progeny group size when detailed reproductive traits are included in a multitrait genetic evaluation
Biosensing on the centrifugal microfluidic lab-on-a-Disc platform
Lab-on-a-Disc (LoaD) biosensors are increasingly a promising solution for many biosensing applications. In the search for a perfect match between point-of-care (PoC) microfluidic devices and biosensors, the LoaD platform has the potential to be reliable, sensitive, low-cost, and easy-to-use. The present global pandemic draws attention to the importance of rapid sample-to-answer PoC devices for minimising manual intervention and sample manipulation, thus increasing the safety of the health professional while minimising the chances of sample contamination. A biosensor is defined by its ability to measure an analyte by converting a biological binding event to tangible analytical data. With evolving manufacturing processes for both LoaDs and biosensors, it is becoming more feasible to embed biosensors within the platform and/or to pair the microfluidic cartridges with low-cost detection systems. This review considers the basics of the centrifugal microfluidics and describes recent developments in common biosensing methods and novel technologies for fluidic control and automation. Finally, an overview of current devices on the market is provided. This review will guide scientists who want to initiate research in LoaD PoC devices as well as providing valuable reference material to researchers active in the field
Risk factors associated with detailed reproductive phenotypes in dairy and beef cows
peer-reviewedThis article was first published in animal, Volume 8, Issue 05, May 2014, pp 695-703, © The Animal Consortium 2014The objective of this study was to identify detailed fertility traits in dairy and beef cattle from transrectal ultrasonography records
and quantify the associated risk factors. Data were available on 148 947 ultrasound observations of the reproductive tract from
75 949 cows in 843 Irish dairy and beef herds between March 2008 and October 2012. Traits generated included (1) cycling at
time of examination, (2) cystic structures, (3) early ovulation, (4) embryo death and (5) uterine score; the latter was measured on a
scale of 1 (good) to 4 (poor) characterising the tone of the uterine wall and fluid present in the uterus. After editing, 72 773
records from 44 415 dairy and beef cows in 643 herds remained. Factors associated with the logit of the probability of a positive
outcome for each of the binary fertility traits were determined using generalised estimating equations; linear mixed model analysis
was used for the analysis of uterine score. The prevalence of cycling, cystic structures, early ovulation and embryo death was
84.75%, 3.87%, 7.47% and 3.84%, respectively. The occurrence of the uterine heath score of 1, 2, 3 and 4 was 70.63%, 19.75%,
8.36% and 1.26%, respectively. Cows in beef herds had a 0.51 odds (95% CI = 0.41 to 0.63, P<0.001) of cycling at the time of
examination compared with cows in dairy herds; stage of lactation at the time of examination was the same in both herd types.
Furthermore, cows in dairy herds had an inferior uterine score (indicating poorer tone and a greater quantity of uterine fluid
present) compared with cows in beef herds. The likelihood of cycling at the time of examination increased with parity and stage of
lactation, but was reduced in cows that had experienced dystocia in the previous calving. The presence of cystic structures on the
ovaries increased with parity and stage of lactation. The likelihood of embryo/foetal death increased with parity and stage of
lactation. Dystocia was not associated with the presence of cystic structures or embryo death. Uterine score improved with parity
and stage of lactation, while cows that experienced dystocia in the previous calving had an inferior uterine score. Heterosis was
the only factor associated with increased likelihood of early ovulation. The fertility traits identified, and the associated risk factors,
provide useful information on the reproductive status of dairy and beef cows.Funding from the Department of Agriculture, Food and Marine Research Stimulus Fund (RSF 11/S/133) and the OptiMIR project is gratefully acknowledged
- …