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Interactions between the Hypothalamic-Pituitary-Adrenal (HPA) Axis, Oxytocin System, and Behavior in Differently Reared Rhesus Monkeys (Macaca mulatta)
Adverse experiences that occur during early critical periods of development modify activity of neuroendocrine systems, such as the hypothalamic-pituitary-adrenal (HPA) axis and oxytocin system. This dissertation examines the effects of nursery rearing, an established model of adverse early experiences, on activity of the HPA axis and oxytocin system in infant and adult rhesus macaques (Macaca mulatta). In addition, influence of oxytocin system activity on the HPA axis and behavioral reactivity was examined. In infant monkeys, nursery-rearing was associated with lower HPA axis, yet higher oxytocin system activity, following the acute stress of developmental assessment. Nursery rearing may result in dysregulation of the HPA axis and a lower overall set point of activity. Mother-reared infants demonstrated higher reactivity during the assessment, which likely reflects a protest response to maternal separation and the strong attachment bond formed in mother-reared infants. Higher oxytocin system activity, lower HPA axis activity, and lower behavioral reactivity during separation and testing in nursery reared monkeys support interactions between HPA axis and oxytocin system activity and corresponds with the pattern of rodent neuroendocrine activity in response to an acute stressor. At 8 months of age, infants were weaned and relocated to mixed-rearing social housing. Infants responded with increased HPA axis and oxytocin system activity that did not vary by rearing condition. Although there was no effect of rearing on overall oxytocin system activity, nursery-reared infants that had been reared with a surrogate-mother, versus rearing with peers, had lower hair cortisol concentrations than mother-reared counterparts at the time of weaning, further supporting the view that nursery-rearing confers a lower set point of HPA axis activity. In contrast, neither HPA axis activity, oxytocin system concentration, nor behavioral reactivity as measured by the Human Intruder Test varied as a function of rearing history in adult rhesus monkeys. This dissertation demonstrates that, although nursery rearing is associated with changes in HPA axis and oxytocin system activity in infant rhesus monkeys, early rearing experiences may not exert prolonged effects. Finally, these data provide some support for an interaction between the HPA axis and oxytocin system, although only during early development
Localized and Expanding Entire Solutions of Reaction-Diffusion Equations
This paper is concerned with the spatio-temporal dynamics of nonnegative
bounded entire solutions of some reaction-diffusion equations in R N in any
space dimension N. The solutions are assumed to be localized in the past. Under
certain conditions on the reaction term, the solutions are then proved to be
time-independent or heteroclinic connections between different steady states.
Furthermore, either they are localized uniformly in time, or they converge to a
constant steady state and spread at large time. This result is then applied to
some specific bistable-type reactions
Symmetry of Traveling Wave Solutions to the Allen-Cahn Equation in \Er^2
In this paper, we prove even symmetry of monotone traveling wave solutions to
the balanced Allen-Cahn equation in the entire plane. Related results for the
unbalanced Allen-Cahn equation are also discussed
Polarization States in B -> rho K* and New Physics
The standard-model explanations of the anomalously-large transverse
polarization fraction fT in B -> phi K* can be tested by measuring the
polarizations of the two decays B+ -> rho+ K*0 and B+ -> rho0 K*+. For the
scenario in which the transverse polarizations of both B -> rho K* decays are
predicted to be large, we derive a simple relation between the fT's of these
decays. If this relation is not confirmed experimentally, this would yield an
unambiguous signal for new physics. The new-physics operators which can account
for the discrepancy in B -> pi K decays will also contribute to the
polarization states of B -> rho K*. We compute these contributions and show
that there are only two operators which can simultaneously account for the
present B -> pi K and B -> rho K* data. If the new physics obeys an approximate
U-spin symmetry, the B -> phi K* measurements can also be explained.Comment: 20 pages, latex, no figures. Minor changes to references and Table 1.
Minor modification of terms; more complete description of triple-product
asymmetry. Analysis and conclusions unchange
Adaptation in a heterogeneous environment II: To be three or not to be
We propose a model to describe the adaptation of a phenotypically structured
population in a -patch environment connected by migration, with each patch
associated with a different phenotypic optimum, and we perform a rigorous
mathematical analysis of this model. We show that the large-time behaviour of
the solution (persistence or extinction) depends on the sign of a principal
eigenvalue, , and we study the dependency of with
respect to . This analysis sheds new light on the effect of increasing the
number of patches on the persistence of a population, which has implications in
agroecology and for understanding zoonoses; in such cases we consider a
pathogenic population and the patches correspond to different host species. The
occurrence of a springboard effect, where the addition of a patch contributes
to persistence, or on the contrary the emergence of a detrimental effect by
increasing the number of patches on the persistence, depends in a rather
complex way on the respective positions in the phenotypic space of the optimal
phenotypes associated with each patch. From a mathematical point of view, an
important part of the difficulty in dealing with , compared to or
, comes from the lack of symmetry. Our results, which are based on a fixed
point theorem, comparison principles, integral estimates, variational
arguments, rearrangement techniques, and numerical simulations, provide a
better understanding of these dependencies. In particular, we propose a precise
characterisation of the situations where the addition of a third patch
increases or decreases the chances of persistence, compared to a situation with
only two patches
Spatial and temporal dynamics of malaria transmission in rural western Kenya
ABSTRACT: BACKGROUND: Understanding the impact of reducing Plasmodium falciparum malaria transmission requires estimates of the relationship between health outcomes and exposure to infectious mosquitoes. However, measures of exposure such as mosquito density and entomological inoculation rate (EIR) are generally aggregated over large areas and time periods, biasing the outcome-exposure relationship. There are few studies examining the extent and drivers of local variation in malaria exposure in endemic areas. METHODS: We describe the spatio-temporal dynamics of malaria transmission intensity measured by mosquito density and EIR in the KEMRI/CDC health and demographic surveillance system using entomological data collected during 2002-2004. Geostatistical zero inflated binomial and negative binomial models were applied to obtain location specific (house) estimates of sporozoite rates and mosquito densities respectively. Model-based predictions were multiplied to estimate the spatial pattern of annual entomological inoculation rate, a measure of the number of infective bites a person receive per unit of time. The models included environmental and climatic predictors extracted from satellite data, harmonic seasonal trends and parameters describing space-time correlation. RESULTS: Anopheles gambiae s.l was the main vector species accounting for 86% (n=2309) of the total collected mosquitoes with the remainder being Anopheles funestus. Sixty eight percent (757/1110) of the surveyed houses had no mosquitoes. Distance to water bodies, vegetation and day temperature were significantly associated with mosquito density. Overall annual point estimates of EIR were 6.7, 9.3 and 9.6 infectious bites per annum for 2002, 2003 and 2004 respectively. Monthly mosquito density and EIR varied over the study period peaking in May during the wet season. The predicted and observed densities and EIR showed a strong seasonal and spatial pattern over the study area. CONCLUSIONS: Spatio-temporal maps of malaria transmission intensity obtained in this study are not only useful in understanding variability in malaria epidemiology over small areas but also provides a high resolution exposure surface that can be used to analyse the impact of malaria exposure on mortalit
KPP reaction-diffusion equations with a non-linear loss inside a cylinder
We consider in this paper a reaction-diffusion system in presence of a flow
and under a KPP hypothesis. While the case of a single-equation has been
extensively studied since the pioneering Kolmogorov-Petrovski-Piskunov paper,
the study of the corresponding system with a Lewis number not equal to 1 is
still quite open. Here, we will prove some results about the existence of
travelling fronts and generalized travelling fronts solutions of such a system
with the presence of a non-linear spacedependent loss term inside the domain.
In particular, we will point out the existence of a minimal speed, above which
any real value is an admissible speed. We will also give some spreading results
for initial conditions decaying exponentially at infinity
Risks linked to accidental inoculation of humans with veterinary vaccines: a 7-year prospective study
AIM: Accidental inoculation of humans with veterinary vaccines can lead to early and late complications. The aim of our study is to describe these complications and their risk factors.
METHODS: Prospective observational study conducted from 2007 to 2014 at Angers University Hospital\u27s Poison Control Centre. The endpoints examined were: early and late locoregional complications, surgical treatment, and absence from work. The statistical analysis was based on a multivariate analysis.
DISCUSSION: The presence of mineral oil adjuvants, the injection of the vaccine under pressure and injection in joint and tendon of the hand significantly increased early locoregional complications and surgery but only the presence of mineral oil adjuvant increased significantly late locoregional complications at one month. Absence from work is significantly correlated to the site of injection and the presence of mineral oil adjuvant.
CONCLUSION: It is important to know about the contents of the veterinary vaccine in order to anticipate early and late complications that may arise (particularly due to the presence of mineral oil adjuvants). Special attention must also be given do the site of injection. We think that any accidental injection of veterinary vaccine into humans, especially those containing mineral oils, must lead to an early medical consultation. This must also be indicated on the product
Spectral stochastic processes arising in quantum mechanical models with a non-L2 ground state
A functional integral representation is given for a large class of quantum
mechanical models with a non--L2 ground state. As a prototype the particle in a
periodic potential is discussed: a unique ground state is shown to exist as a
state on the Weyl algebra, and a functional measure (spectral stochastic
process) is constructed on trajectories taking values in the spectrum of the
maximal abelian subalgebra of the Weyl algebra isomorphic to the algebra of
almost periodic functions. The thermodynamical limit of the finite volume
functional integrals for such models is discussed, and the superselection
sectors associated to an observable subalgebra of the Weyl algebra are
described in terms of boundary conditions and/or topological terms in the
finite volume measures.Comment: 15 pages, Plain Te
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