1,130 research outputs found
Isolation and primary cultures of human intrahepatic bile ductular epithelium
A technique for the isolation of human intrahepatic bile ductular epithelium, and the establishment of primary cultures using a serum- and growth-factor-supplemented medium combined with a connective tissue substrata is described. Initial cell isolates and monolayer cultures display phenotypic characteristics of biliary epithelial cells (low molecular weight prekeratin positive; albumin, alphafetoprotein, and Factor VIII-related antigen negative). Ultrastructural features of the cultured cells show cell polarization with surface microvilli, numerous interepithelial junctional complexes and cytoplasmic intermediate prekeratin filaments. © 1988 Tissue Culture Association, Inc
Nitric oxide as a mediator of inflammation?—You had better believe it
Nitric oxide has enigmatic qualities in inflammation. In order to appreciate the precise contributions of nitric oxide to a pathophysiological process, one must account for enzyme source, coproduction of oxidants and antioxidant defences, time, rate of nitric oxide production, cellular source, peroxynitrite formation and effects on DNA (mutagenesis/apoptosis). We contend that there is ample evidence to consider nitric oxide as a molecular aggressor in inflammation, particularly chronic inflammation. Therapeutic benefit can be achieved by inhibition of inducible nitric oxide synthase and not the donation of additional nitric oxide. Furthermore, there is growing appreciation that nitric oxide and products derived thereof, are critical components linking the increased incidence of cancer in states of chronic inflammation
Dipolar and scalar He and Xe frequency shifts in mm-sized cells
We describe a He-Xe comagnetometer operating in stemless
anodically bonded cells with a 6 mm volume and a Xe spin coherence
time of 300 sec. We use a Rb pulse-train magnetometer with co-linear
pump and probe beams to study the nuclear spin frequency shifts caused by spin
polarization of He. By systematically varying the cell geometry in a
batch cell fabrication process we can separately measure the cell shape
dependent and independent frequency shifts. We find that a certain aspect ratio
of the cylindrical cell can cancel the effects of He magnetization that
limit the stability of vapor-cell comagnetometers. Using this control we also
observe for the first time a scalar He-Xe collisional frequency
shift characterized by an enhancement factor .Comment: 4 pages, 4 figure
Interactive effects between nest microclimate and nest vegetation structure confirm microclimate thresholds for Lesser Prairie-Chicken nest survival
Citation: Grisham, B. A., Godar, A. J., Boal, C. W., & Haukos, D. A. (2016). Interactive effects between nest microclimate and nest vegetation structure confirm microclimate thresholds for Lesser Prairie-Chicken nest survival. Condor, 118(4), 728-746. doi:10.1650/CONDOR-16-38.1The range of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) spans 4 unique ecoregions along 2 distinct environmental gradients. The Sand Shinnery Oak Prairie ecoregion of the Southern High Plains of New Mexico and Texas is environmentally isolated, warmer, and more arid than the Short-Grass, Sand Sagebrush, and Mixed-Grass Prairie ecoregions in Colorado, Kansas, Oklahoma, and the northeast panhandle of Texas. Weather is known to influence Lesser Prairie-Chicken nest survival in the Sand Shinnery Oak Prairie ecoregion; regional variation may also influence nest microclimate and, ultimately, survival during incubation. To address this question, we placed data loggers adjacent to nests during incubation to quantify temperature and humidity distribution functions in 3 ecoregions. We developed a suite of a priori nest survival models that incorporated derived microclimate parameters and visual obstruction as covariates in Program MARK. We monitored 49 nests in Mixed-Grass, 22 nests in Sand Shinnery Oak, and 30 nests in Short-Grass ecoregions from 2010 to 2014. Our findings indicated that (1) the Sand Shinnery Oak Prairie ecoregion was hotter and drier during incubation than the Mixed- and Short-Grass ecoregions; (2) nest microclimate varied among years within ecoregions; (3) visual obstruction was positively associated with nest survival; but (4) daily nest survival probability decreased by 10% every half-hour when temperature was greater than 34°C and vapor pressure deficit was less than - 23 mmHg during the day (about 0600-2100 hours). Our major finding confirmed microclimate thresholds for nest survival under natural conditions across the species' distribution, although Lesser Prairie-Chickens are more likely to experience microclimate conditions that result in nest failures in the Sand Shinnery Oak Prairie ecoregion. The species would benefit from identification of thermal landscapes and management actions that promote cooler, more humid nest microclimates. © 2016 Cooper Ornithological Society
Neuropsychological and neurophysiological insights into hoarding disorder
Hoarding disorder (HD) is associated with significant personal impairment in function and constitutes a severe public health burden. Individuals who hoard experience intense distress in discarding a large number of objects, which results in extreme clutter. Research and theory suggest that hoarding may be associated with specific deficits in information processing, particularly in the areas of attention, memory, and executive functioning. There is also growing interest in the neural underpinnings of hoarding behavior. Thus, the primary aim of this review is to summarize the current state of evidence regarding neuropsychological deficits associated with hoarding and review research on its neurophysiological underpinnings. We also outline the prominent theoretical model of hoarding and provide an up-to-date description of empirically based psychological and medical treatment approaches for HD. Finally, we discuss important future avenues for elaborating our model of HD and improving treatment access and outcomes for this disabling disorder
Time-Clamped, RPE-Matched Treadmill Activity and Interactive Video Game Dancing Differ in Step Count But Not Heart Rate Response
Background: Participation in regular moderate or vigorous physical activity (MVPA) results in numerous health benefits. Task enjoyment is a known antecedent and promoter of regular activity engagement. Participation in interactive video gaming has increased in recent years. Purpose: The aims of the present investigation were to: 1) determine heart rate (HR) and step count outcomes of time-clamped and RPE-matched interactive video game dancing (VGD) and treadmill activity; 2) characterize the suitability of VGD to achieve MVPA designation; and, 3) investigate step count outcomes recorded by pedometry and accelerometry. Methods: Subjects underwent three testing sessions with the latter two randomized. During the familiarization visit, the perceived exertion (Borg RPE) of an interactive VGD activity was determined and a treadmill speed that resulted in an RPE-matched exertion level was identified through incremental increases in treadmill speed. On subsequent visits, subjects completed 15 minutes of VGD or RPE-matched treadmill activity. HR and step count were measured during both sessions. Results: Nine participants (Age 19.8 ± 1.6; 5 males; 4 females) volunteered. With time-clamped and RPE-matched, the average HR for dancing 154.7 (± 21.8) and treadmill activity 157.8 (± 25.1) were not different (p = 0.698). The selected dances for the VGD activity resulted in 8/9 subjects exercising at MVPA intensity according to percent of predicted maximal HR (threshold of 64% maximal HR; equation: 207 – 0.7*Age). Steps completed during dancing and treadmill activity according to pedometry were 1510 (± 488) and 2066 (± 247), respectively, with the difference being significant (p = 0.001). Steps completed during dancing and the treadmill activity according to accelerometry were 988 (± 256) and 1938 (± 119), respectively, with the difference again significant (p \u3c 0.001). The within-mode, between-device step count (pedometer vs. accelerometer, respectively) were also of interest. For dancing, a significant difference (p \u3c 0.001) was noted as 1510 (± 488) vs. 988 (± 256) steps. For treadmill activity, the disparity between 2066 (± 247) vs. 1938 (± 119) was also different (p = 0.042). Discussion: The HR response of a VGD activity was not different than a time-clamped, RPE-matched treadmill activity. Furthermore, VGD achieved designation as MVPA intensity in 8/9 subjects with the lone subject failing to achieve moderate designation by a single beat. Of note, objectively determined step count varied by mode and measuring device illustrating the need to employee prudency when selecting measuring technique for step count during rhythmic vs. non-rhythmic PA
MIXING OF TWO GREATER SANDHILL CRANE POPULATIONS IN NORTHEAST OREGON
The Oregon Department of Fish and Wildlife (ODFW) Ladd Marsh Wildlife Area in northeast Oregon hosts a small group of nesting greater sandhill cranes (Grus canadensis tabida). There were no data on where these birds wintered, and we had no understanding of how these birds fit into the larger picture of western sandhill crane population delineation. ODFW began color-banding pre-fledging colts in 2007 and added satellite tracking with platform transmitter terminals (PTTs) in 2015. To date, we have captured 15 colts and 13 adults and marked them with color bands. We also fitted 1 colt and 8 adult cranes with PTTs. In fall 2015, all 3 PTT-marked birds traveled to wintering grounds in the Central Valley and Central Coast ecoregions of California. In fall 2016, of 5 PTT-marked cranes, 4 traveled to the Central Valley and Central Coast ecoregions of California. The fifth individual migrated south through Idaho and Nevada to the Lower Colorado River Valley. The PTT data from our study highlight the need for additional research on the validity of current western sandhill crane population divisions
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Recent advances in remote handling at LAMPF
The Clinton P. Anderson Meson Physics Facility (LAMPF) has operated at beam currents above 200 microamperes since 1976. As a result, the main experimental beam line (Line A) has become increasingly radioactive over the years. Since 1976 the radiation levels have steadily increased from 100 mR/hr to levels that exceed 10,000 R/hr in the components near the pion production targets. During this time the LAMPF remote handling system, Monitor, has continued to operate successfully in the ever-increasing radiation levels, as well as with more complex remote-handling situations. This paper briefly describes the evolution of Monitor and specifically describes the complete rebuild of the A-6 target area, which is designated as the beam stop, but also includes isotope production capabilities and a primitive neutron irradiation facility. The new facility includes not only the beam stop and isotope production, but also facilities for proton irradiation and a ten-fold expansion in neutron irradiation facilities
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