1,384 research outputs found
A Marine Incursion in the Lower Pennsylvanian Tynemouth Creek Formation, Canada:Implications for Paleogeography, Stratigraphy and Paleoecology
A modified apparatus for dual, sterilized, isolated perfusion of the rat liver
The isolated perfused rat liver (IPRL) has proven to be a useful model for the study of physiology and pathology of the liver. For research in nonparenchymal cell (NPC) function that includes measurement of cytokine production (eg, TNF), it is necessary to have a sterilized perfusion system. We have modified the IPRL apparatus so as to be able to perform sterile perfusions of two livers simultaneously. The perfusion apparatus is a recirculating closed system in which the oxygenator is a plastic container separated into two chambers by a fenestrated plastic wall. A disposable macropore filter functions as both a bubble trap and perfusate filter. The sterilization process is done by immersing the various components in Benz-All solution. The tubing is disinfected by irrigation with 10% Clorox followed by 0.9% sodium chloride solution. The perfusate used is filter-sterilized Krebs buffer solution containing 0.5 g Mandol/250 mL perfusate. Not only can two organs be conveniently perfused simultaneously, but the entire system can be reliably sterilized for up to 20 consecutive perfusions. Bile production is higher and more stable with less leakage of intracellular enzymes. Many of the components are disposable and can be altered to suit the needs of a particular experiment. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted
Isospin violation and the proton's neutral weak magnetic form factor
The effects of isospin violation on the neutral weak magnetic form factor of
the proton are studied using two-flavour chiral perturbation theory. The first
nonzero contributions appear at O(p^4) in the small-momentum expansion, and the
O(p^5) corrections are also calculated. The leading contributions from an
explicit Delta(1232) isomultiplet are included as well. At such a high order in
the chiral expansion, one might have expected a large number of unknown
parameters to contribute. However, it is found that no unknown parameters can
appear within loop diagrams, and a single tree-level counterterm at O(p^4) is
sufficient to absorb all divergences. The momentum dependence of the neutral
weak magnetic form factor is not affected by this counterterm.Comment: 26 pages including 9 figure
Efficacy of ERL-4221 as an ovotoxin for feral pigs (\u3ci\u3eSus scrofa\u3c/i\u3e)
Context. The expansion of feral pig populations across the United States has increased the occurrence of damage and damage complaints.Newtechniques are needed to more effectively manage feral pig damage, including the development of fertility control agents.
Aims. We aimed to assess the ovotoxic properties of ERL-4221 as a candidate fertility control agent for feral pigs.
Methods. We conducted two palatability trials to determine ERL-4221 acceptance and one experimental trial with ERL- 4221 at the captive wildlife facility of Texas A&M University-Kingsville during 2008. Our experimental trial had three treatments, a control containing no ERL-4221, baits containing 16.0 mg ERL-4221 kg–1 bodyweight for 10 days, and baits containing 16.0 mg ERL-4221 kg–1 bodyweight for 20 days.
Key results. Final body mass, total ovary mass, number of follicles and number of corpora lutea did not differ between treatments.
Conclusions. We did not find it efficacious to orally deliver ERL-4221 to feral pigs to reduce fertility. Oral delivery is the most practical, cost-effective means of delivering fertility control agents to feral pigs and development of additional fertility control strategies are needed.
Implications. Unless ovotoxic effects of ERL-4221 can be identified in feral pigs, along with a successful means of administration, other fertility control strategies may need to be explored, such as oocyte-secreted proteins that regulate follicular development
The nucleon's strange electromagnetic and scalar matrix elements
Quenched lattice QCD simulations and quenched chiral perturbation theory are
used together for this study of strangeness in the nucleon. Dependences of the
matrix elements on strange quark mass, valence quark mass and momentum transfer
are discussed in both the lattice and chiral frameworks. The combined results
of this study are in good agreement with existing experimental data and
predictions are made for upcoming experiments. Possible future refinements of
the theoretical method are suggested.Comment: 24 pages, 9 figure
Fine-scale genetic and social structuring in a central Appalachian white-tailed deer herd
Spatial genetic structure in white-tailed deer (Odocoileus virginianus) has been examined at regional scales, but genetic markers with the resolution to detect fine-scale patterns have appeared only recently. We used a panel of microsatellite DNA markers, radiotelemetry data, and visual observations of marked deer to study fine-scale social and genetic structure in a high-density population of white-tailed deer (12-20 deer/km 2 ). We collected genetic data on 229 adult females, 102 of which were assigned to 28 social groups. Our results were consistent with the conceptual model of white-tailed deer social structure, where philopatric females form social groups composed of related individuals. Within-group relatedness values approached the expected value for 1st cousins (R 5 0.103, SE 5 0.033), but individuals among groups (R 5 20.014, SE 5 0.003) and overall (R 5 20.009, SE 5 0.003) were unrelated. Fixation indices revealed a significant departure from equilibrium values among social groups (F ST 5 0.076, SE 5 0.007) and an excess of heterozygotes within groups (F IS 5 20.050, SE 5 0.018), consistent with theoretical expectations for mammal populations characterized by female philopatry and a polygynous mating system. Analyses of spatial autocorrelation indicated genetic structuring occurred at a very fine spatial scale, where pairs of adult females within 1 km were genetically nonindependent. The occurrence of fine-scale genetic and social structure has implications for the ecology and management of white-tailed deer, including habitat use and resource competition, offspring sex allocation theories, disease transmission, and the consideration of social behaviors in management
Prospectus, February 15, 1984
ELECTION RESULTS; News Digest; Blacks added to local history; Letter from the editor; Letter to the editor; Letter to the editor; PC Happenings: Real estate review workshop, Lifelong Learners to meet, Story shop stimulates young writers, EMT assessment workshop offered; Gameroom damage--why!!; Student award; Letter to the editor; Roberts nominated; Book Review: Making College Pay Off ; Reflections and contemplations; Student needs witness; Division chairman believes in Parkland; \u27Images\u27 needs you; Dodd explains his position on Miller; Did You Know...; Coach encouraged at team\u27s success; Wheelchair games postponed; Fewer students at Parkland; Bushman and Gunter; Survival trip taken; \u27Shadows Beyond the Benefit....\u27 entices thinking; Davis says farewell; Eclectic collection of art; Creative Corner...Especially for you!!: Freedom, To God, A Worn-out photograph, Memories, Clouds, The Spreading Flame, Why, Haunting Beauty, Lost Love, The Wheel of Fortune, What Is the Vocal?, The Petals of Marie, Unknown, No Defeat, A Tribute to Fallen Hero; John Watching ; King led the way for blacks in the 1960\u27s; Anti-discrimination pledge signed; Rosa Parks remembered; Black colleges pitch into nationwide crisis; Play review; Dream becomes day-to-day reality; Increase Awareness of Financial Aid Available; Colored Girls stresses stereotyping; Yaxley scholarship; Black collection extensive; \u27Operation Snowball\u27 helps teens help themselves; In the Library-- P Section; Question: Do you think we will ever attain world peace?; Classifieds; \u27Four Seasons\u27 blast of fresh air; Campus Paperback Bestsellers; New & Recommended; Another political album for U2 with \u27Under a Blood Red Sky\u27; New Dorothy after 45 years; Institute shows rare independent British films; Film festival schedule; MTV--a hit that\u27s here to stay; Utopia reminds us that it is 1984; Silkwood should be seen by all; Nicaragua, a problem the U.S. should study now; Trout remembers when; I.M. News; Wulf recalls coaching days; Carper recalls Parkland; Martin wins triple jump at meet; Composite athletic schedule; Competition aids inequalityhttps://spark.parkland.edu/prospectus_1984/1031/thumbnail.jp
An aging Interventions Testing Program: study design and interim report
The National Institute on Aging's Interventions Testing Program (ITP) has developed a plan to evaluate agents that are considered plausible candidates for delaying rates of aging. Key features include: (i) use of genetically heterogeneous mice (a standardized four-way cross), (ii) replication at three test sites (the Jackson Laboratory, TJL; University of Michigan, UM; and University of Texas, UT), (iii) sufficient statistical power to detect 10 changes in lifespan, (iv) tests for age-dependent changes in T cell subsets and physical activity, and (v) an annual solicitation for collaborators who wish to suggest new interventions for evaluation. Mice in the first cohort were exposed to one of four agents: aspirin, nitroflurbiprofen (NFP), 4-OH- -phenyl-N-tert-butyl nitrone (4-OH-PBN), or nordihydroguiaretic acid (NDGA). An interim analysis was conducted using survival data available on the date at which at least 50 of the male control mice had died at each test site. Survival of control males was significantly higher, at the interim time-point, at UM than at UT or TJL; all three sites had similar survival of control females. Males in the NDGA group had significantly improved survival ( P 0.0004), with significant effects noted at TJL ( P < 0.01) and UT ( P < 0.04). None of the other agents altered survival, although there was a suggestion ( P 0.07) of a beneficial effect of aspirin in males. More data will be needed to determine if any of these compounds can extend maximal lifespan, but the current data show that NDGA reduces early life mortality risks in genetically heterogeneous mice at multiple test sites.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74625/1/j.1474-9726.2007.00311.x.pd
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