34 research outputs found
Predicting chemical impacts on vertebrate endocrine systems
Animals have evolved diverse protective mechanisms for responding to toxic chemicals of both natural and anthropogenic origin. From a governmental regulatory perspective, these protective responses complicate efforts to establish acceptable levels of chemical exposure. To explore this issue, we considered vertebrate endocrine systems as potential targets for environmental contaminants. Using the hypothalamic-pituitary-thyroid (HPT), hypothalamic-pituitary-gonad (HPG), and hypothalamic-pituitary-adrenal (HPA) axes as case examples, we identified features of these systems that allow them to accommodate and recover from chemical insults. In doing so, a distinction was made between effects on adults and those on developing organisms. This distinction was required because endocrine system disruption in early life stages may alter development of organs and organ systems, resulting in permanent changes in phenotypic expression later in life. Risk assessments of chemicals that impact highly regulated systems must consider the dynamics of these systems in relation to complex environmental exposures. A largely unanswered question is whether successful accommodation to a toxic insult exerts a fitness cost on individual animals, resulting in adverse consequences for populations. Mechanistically based mathematical models of endocrine systems provide a means for better understanding accommodation and recovery. In the short term, these models can be used to design experiments and interpret study findings. Over the long term, a set of validated models could be used to extrapolate limited in vitro and in vivo testing data to a broader range of untested chemicals, species, and exposure scenarios. With appropriate modification, Tier 2 assays developed in support of the U.S. Environmental Protection Agency's Endocrine Disruptor Screening Program could be used to assess the potential for accommodation and recovery and inform the development of mechanistically based models. Environ. Toxicol. Chem. 2011;30:39–51. © 2010 SETACPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78495/1/376_ftp.pd
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Bisphenol A Exposure During Early Development Induces Sex-Specific Changes in Adult Zebrafish Social Interactions
Developmental bisphenol A (BPA) exposure is associated with adverse behavioral
effects, although underlying modes of action remain unclear. Because BPA is a
suspected xenoestrogen, the objective was to identify sex-based changes in adult
zebrafish social behavior developmentally exposed to BPA (0.0, 0.1 or 1 μM) or one of
two control compounds (0.1 μM 17β-estradiol [E2], and 0.1 μM GSK4716, a synthetic
estrogen-related receptor γ ligand). A test chamber was divided lengthwise so each
arena held one fish unable to detect the presence of the other fish. A mirror was
inserted at one end of each arena; baseline activity levels were determined without mirror. Arenas were divided into 3, computer-generated zones to represent different
distances from mirror image. Circadian rhythm patterns were evaluated at 1-3 (= AM)
and 5-8 (= PM) hr postprandial. Adult zebrafish were placed into arenas and monitored
by digital camera for 5 min. Total distance traveled, % time spent at mirror image, and
number of attacks on mirror image were quantified. E2, GSK4716, and all BPA
treatments dampened male activity and altered male circadian activity patterns; there
was no marked effect on female activity. BPA induced non-monotonic effects (response
curve changes direction within range of concentrations examined) on male % time at
mirror only in AM. All treatments produced increased % time at the mirror during PM.
Male attacks on the mirror were reduced by BPA exposure only during AM. There were
sex-specific effects of developmental BPA on social interactions and time-of-day of
observation affected results.Keywords: social behavior, bisphenol A, agonistic behavior, developmental exposure, zebrafish, circadian rhythms, sex-specific behavio
Outcomes in a community sex offender treatment program: A comparison between polygraphed and matched non-polygraphed offenders. Sexual Abuse: A
Abstract This study compared a group of 104 adult male sex offenders who received community cognitive-behavioral treatment, correctional supervision, and periodic polygraph compliance exams with a matched group of 104 sex offenders who received the same type of treatment and supervision services but no polygraph exams. Polygraph exams focused on whether participants were following their conditions of community supervision and treatment and had avoided committing new sexual offenses. The two groups were exact pair-wise matched on three variables: (1) Static-99 risk score (Hanson & Thornton 2000, Law and Human Behavior, 24, 119-136), (2) status as a completer of prison sex offender treatment, and (3) date placed in the community. At fixed 5-year follow-up periods, the number of individuals in the polygraph group charged with committing a new non-sexual violent offense was significantly lower than in the no polygraph group (2.9% versus 11.5%). However, there were no significant between-group differences for the number of individuals charged for new sexual (5.8% versus 6.7%), any sexual or violent (8.7% versus 16.3%), or any criminal offense (39.4% versus 34.6%). The results are discussed in terms of their clinical and research implications
Oligocene deformation of the Chuandian terrane in the SE margin of the Tibetan Plateau related to the extrusion of Indochina
Mechanisms driving the tectonic evolution of the southeast (SE) margin of Tibet include the Paleogene extrusion of the coherent Indochina lithospheric block, and the continuous deformation caused by lower crustal flow since the middle Miocene. The timing and style of regional deformations are key to determining the role of each mechanism. Fault-bounded and -controlled Cenozoic basins within the SE margin of Tibet record regional deformation, surface uplift and variations in paleoclimate, but often are poorly dated. New magnetostratigraphy and 40Ar/39Ar dating of volcanic ashes constrain precisely the timing of sedimentation within the Lühe Basin to between ~35 and 26.5 Ma. The basin is located in the Chuandian terrane along the Chuxiong fault, which lies ~70 km north of, and parallel to, the Ailao Shan-Red River fault. The asymmetric syncline of the Lühe Basin suggests syn-contractional sedimentation and the basal age of the basin represents the initiation of the Chuxiong fault and crustal shortening at ~35 Ma. This is coincident with the onset of the Ailao Shan-Red River fault, and supports a kinematic link between them. Our study suggests that, like the Ailao Shan-Red River fault, the Chuxiong fault is a Paleogene transpressional structure that developed during the extrusion and clockwise rotation of Indochina around the Eastern Himalayan Syntaxis, which caused the late Paleogene deformation and surface uplift of the Chuandian terrane and Indochina. Our revised chronostratigraphy of the Lühe Basin provides further evidence that many of the “Neogene” sedimentary basins in the SE margin of Tibet may be much older than previously thought
The Vehicle, Fall 1992
Table of Contents
DeconstructivismPeter F. Essigpage 5
Homecoming Pep RallyPeter F. Essigpage 6
McAfee GymnasiumWalt Howardpage 7
Morton ParkAnn Moutraypage 9
Why The Willows WeepPeter F. Essigpage 10
UntitledStephen P. Carmodypage 10
A Stranger\u27s MorningBen Hausmannpage 11
deMONSTERative pronounsJoAnna Wolaverpage 12
2.5%Jill S. Pilonpage 13
The BottleStacey Kruegerpage 14
Suppression Jean K. Graypage 15
ProgressStacey Kruegerpage 16
Daily LessonsJennifer Moropage 17
Sunset TheaterMichelle R. Hokepage 20
Eagle GT\u27sJarrod T. Shieldspage 21
New HouseRandy Lisspage 22
UntitledStephen P. Carmodypage 23
Renting Classics on a Saturday NightNancy Jamespage 24
UntitledJacqueline Hallpage 25
Alone While He SleepsSandy Beauchamppage 26
Sand and SeaThomas Schnarrepage 27
loveMichelle R. Hokepage 28
Backward Ass Junkie FunkSandy Beauchamppage 28
These Things You KeepTom McGrathpage 29
Springhill CrestRobert M. Reutherpage 30
The Pass OverLarry Irvinpage 31
The Stolen ChildTom McGrathpage 32
Before the Recycling KickWalt Howardpage 37
Authors\u27 Pagepage 38https://thekeep.eiu.edu/vehicle/1058/thumbnail.jp
Sustained Delivery of Activated Rho GTPases and BDNF Promotes Axon Growth in CSPG-Rich Regions Following Spinal Cord Injury
Background: Spinal cord injury (SCI) often results in permanent functional loss. This physical trauma leads to secondary events, such as the deposition of inhibitory chondroitin sulfate proteoglycan (CSPG) within astroglial scar tissue at the lesion. Methodology/Principal Findings: We examined whether local delivery of constitutively active (CA) Rho GTPases, Cdc42 and Rac1 to the lesion site alleviated CSPG-mediated inhibition of regenerating axons. A dorsal over-hemisection lesion was created in the rat spinal cord and the resulting cavity was conformally filled with an in situ gelling hydrogel combined with lipid microtubes that slowly released constitutively active (CA) Cdc42, Rac1, or Brain-derived neurotrophic factor (BDNF). Treatment with BDNF, CA-Cdc42, or CA-Rac1 reduced the number of GFAP-positive astrocytes, as well as CSPG deposition, at the interface of the implanted hydrogel and host tissue. Neurofilament 160kDa positively stained axons traversed the glial scar extensively, entering the hydrogel-filled cavity in the treatments with BDNF and CA-Rho GTPases. The treated animals had a higher percentage of axons from the corticospinal tract that traversed the CSPG-rich regions located proximal to the lesion site. Conclusion: Local delivery of CA-Cdc42, CA-Rac1, and BDNF may have a significant therapeutic role in overcoming CSPGmediate
Preexisting Japanese Encephalitis Virus Neutralizing Antibodies and Increased Symptomatic Dengue Illness in a School-Based Cohort in Thailand
Dengue viruses (DENVs) and Japanese encephalitis virus (JEV) have significant cross-reactivity in serological assays, but the possible clinical implications of this remain poorly understood. Interactions between these flaviviruses are potentially important for public health because wild-type JEV continues to co-circulate with DENV in Southeast Asia, the area with the highest burden of DENV illness, and JEV vaccination coverage in this region is high. In this study, we examined how preexisting JEV neutralizing antibodies (NAbs) influenced the clinical severity of subsequent DENV infection using data from a prospective school-based cohort study in Thailand that captured a wide range of clinical severities, including asymptomatic, non-hospitalized, and hospitalized DENV infections. We found that the prior existence of JEV NAbs was associated with an increased occurrence of symptomatic versus asymptomatic DENV infection. This association was most notable in DENV-naives, in whom the presence of JEV NAbs was also associated with an illness of longer duration. These findings suggest that the issue of heterologous flavivirus immunity and DENV infection merits renewed attention and interest and that DENV vaccine developers might incorporate detailed assessments of preexisting immunity to non-DENV flaviviruses and histories of vaccination against non-DENV flaviviruses in evaluating DENV vaccine safety and efficacy
Separation – integration – and now …? - An historical perspective on the relationship between German management accounting and financial accounting
German accounting has traditionally followed a dual ledger approach with strictly separated internal cost accounting, as the basis for management information, and external financial accounting focusing on creditor protection and based on the commercial law. However, the increased adoption of integrated accounting system implies a significant change in the relationship between financial and management accounting systems. We use Hegelian dialectic to trace the historical development of German accounting from separated systems towards antithetical propositions of full integration, and the emergence of partial integration as the synthesis of this transformation process. For this reason, our paper provides a comprehensive analysis of the literature on the relationship between financial and management accounting in Germany. On this basis, we elaborate how financial accounting in Germany has been shaped by its economic context and legislation, and how financial accounting – accompanied by institutional pressures – in turn influenced management accounting. We argue that the changing relationship between management and financial accounting in the German context illustrates how current accounting practice is shaped not only by its environment, but also by its historical path. Based on this reasoning, we discuss several avenues for future research
Understanding the performance of community health volunteers involved in the delivery of health programmes in underserved areas: a realist synthesis
Electronic Structure and Transition Energies in Polymer–Fullerene Bulk Heterojunctions
© 2014 American Chemical Society. Photocurrent spectroscopy is used to measure both the charge transfer and exciton optical absorption spectra of various bulk heterojunction organic solar cells. The energy difference between the polymer HOMO energy and the fullerene LUMO energy is obtained from the spectra, along with the disorder energy. Combining information from cells with several different polymers and fullerenes allows measurements of the energy differences between HOMO or LUMO energies for about 10 different polymers and fullerenes, with an estimated uncertainty of 50 meV. Heterojunction band offsets are obtained for the various cells, distinguishing between the excitonic and the single-carrier band offsets. The cell open-circuit voltage is shown to be closely correlated with the interface band gap. The exciton disorder energy is directly correlated to the band-tail disorder and we also consider the effects of exciton thermalization on the charge generation mechanism. The data indicate that an energy offset between the polymer exciton and the charge transfer ground state below about 0.25 eV adversely affects the cell performance, while a HOMO band offset below about 0.2-0.3 eV also degrades cell performance but by a different mechanism