Most studies posit and identify a linear and negative relationship between democracy and the violation of human rights. Some research challenges this finding, however, suggesting that nonlinear influences exist. Within this article, we examine the structure of the relationship between democracy and repression during the time period from 1976 to 1996. To conduct our analysis, we utilize diverse statistical approaches which are particularly flexible in identifying influences that take a variety of functional forms (specifically LOESS and binary decomposition). Across measures and methodological techniques, we found that below a certain level, democracy has no impact on human rights violations, but above this level democracy influences repression in a negative and roughly linear manner. The implications of this research are discussed within the conclusion.

Exposure to maternal mood disorder in utero may program infant neurobehavior via DNA methylation of the glucocorticoid receptor (NR3C1) and 11β-hydroxysteroid dehydrogenase type 2 ( 11β-HSD-2), two placental genes that have been implicated in perturbations of the hypothalamic pituitary adrenocortical (HPA) axis. We tested the relations among prenatal exposure to maternal depression or anxiety, methylation of exon 1F of NR3C1 and 11β-HSD-2, and newborn neurobehavior. Controlling for relevant covariates, infants whose mothers reported depression during pregnancy and showed greater methylation of placental NR3C1 CpG2 had poorer self-regulation, more hypotonia, and more lethargy than infants whose mothers did not report depression. On the other hand, infants whose mothers reported anxiety during pregnancy and showed greater methylation of placental 11β-HSD-2 CpG4 were more hypotonic compared with infants of mothers who did not report anxiety during pregnancy. Our results support the fetal programming hypothesis and suggest that fetal adjustments to cues from the intrauterine environment, in this case an environment that could be characterized by increased exposure to maternal cortisol, may lead to poor neurodevelopmental outcomes.

The contribution of the T cell chemoattractant chemokine IFN-inducible protein 10 (IP-10) in host defense following viral infection of the CNS was examined. IP-10 is expressed by astrocytes during acute encephalomyelitis in mouse hepatitis virus-infected mice, and the majority of T lymphocytes infiltrating into the CNS expressed the IP-10 receptor CXCR3. Treatment of mice with anti-IP-10 antisera led to increased mortality and delayed viral clearance from the CNS as compared with control mice. Further, administration of anti-IP-10 led to a >70% reduction (p ≤ 0.001) in CD4+ and CD8+ T lymphocyte infiltration into the CNS, which correlated with decreased (p ≤ 0.01) levels of IFN-γ. These data indicate that IP-10 functions as a sentinel molecule in host defense and is essential in the development of a protective Th1 response against viral infection of the CNS.

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Induction of a Th1 immune response against viral infection of the CNS is important in contributing to viral clearance. The present studies demonstrate a role for the T cell chemoattractant chemokine Mig (monokine induced by IFN-γ) in contributing to a Th1 response against mouse hepatitis virus infection of the CNS. Analysis of the kinetics of Mig expression revealed mRNA transcripts present at days 7 and 12 postinfection (p.i.) but not early (day 2) or late (day 35) in the infection. To determine functional significance, mouse hepatitis virus-infected mice were treated with anti-Mig antisera, and the severity of disease was evaluated. Such treatment resulted in a marked increase in mortality that correlated with a >3 log increase in viral burden within the brains as compared with control mice treated with normal rabbit serum. Anti-Mig-treated mice displayed a significant decrease (p < 0.005) in CD4+ and CD8+ T cell recruitment into the CNS as compared with normal rabbit serum-treated mice. In addition, anti-Mig treatment resulted in a significant decrease (p < 0.05) in levels of IFN-γ and IFN-β that coincided with increased (p < 0.02) expression of the anti-inflammatory Th2 cytokine IL-10 within the CNS. Collectively, these data indicate that Mig is important in contributing to host defense by promoting a protective Th1 response against viral infection of the CNS.

Abundance of early juvenile Dungeness crab (Cancer magister) is dramatically higher in intertidal shell habitats compared to mud habitats in several coastal estuaries of the Pacific Northwest. To define the mechanisms underlying this habitat—specific pattern in abundance, we concurrently examined four components of recruitment to intertidal shell and mud habitats at two locations within the Grays Harbor estuary (Washington, USA): (1) water column supply of crab megalopae (postlarvae); (2) settlement patterns of crab megalopae 8 h after settlement substrates were deployed; (3) density of first benthic juvenile instars (J1) 48 h after deployment of such substrates; and (4) density of early juvenile crab in shell and mud habitats over a 4—mo period. We also describe the physical processes likely to be influencing postlarval supply within Grays Harbor, and take advantage of natural variation in postlarval supply between two locations, in combination with a predator exclusion experiment, to define the relative importance of postlarval supply vs. post—settlement survival in regulating population size of juvenile crab in certain intertidal habitats. Water column postlarval supply (measured with plankton and neuston nets, and artificial settlement substrates) in terms of both megalopal density (number per cubic metre) and flux (number per hour) was significantly higher in the southern part of the estuary vs. the northern part during a week—long settlement pulse. Our field observations and measurements suggest that spatial variation in postlarval supply was due to local differneces in wind—driven surface currents, since tidal current speeds in the two locations were similar. More—over, there was no correlation between current speed and flux of megalopae over the bottom. There was generally no difference in postlarval supply between shell and mud habitats. Our experimental results further indicate that: (1) the abundance of recently settled crab megalopae in 0.25 m2 settlement trays was significantly higher in shell than in mud habitats, irrespective of whether the trays were placed in 3—5 ha of shell vs. mud; (2) there was a positive and significant correlation between postlarval supply and density of megalopae in shell and mud habitats; and (3) there was a positive and significant correlation between postlarval supply and density of J1 instars only in habitats where specific predators were excluded. Once the number of J1 instars at both geographical locations was reduced to similar levels, equivalent but steadily decreasing densities persisted throughout the summer growing season. The decoupling of settlement patterns and density of J1 instars took place within our 48—h sampling interval. Thus, future attempts to examine the correspondence between larval supply and post—settlement abundance of marine benthic species with planktonic larvae should do so at extremely small temporal scales or a critical life history phase may be overlooked. The results from this study demonstrate that substrate selection can affect distributi...

BackgroundPrenatal socioeconomic adversity as an intrauterine exposure is associated with a range of perinatal outcomes although the explanatory mechanisms are not well understood. The development of the fetus can be shaped by the intrauterine environment through alterations in the function of the placenta. In the placenta, the HSD11B2 gene encodes the 11-beta hydroxysteroid dehydrogenase enzyme, which is responsible for the inactivation of maternal cortisol thereby protecting the developing fetus from this exposure. This gene is regulated by DNA methylation, and this methylation and the expression it controls has been shown to be susceptible to a variety of stressors from the maternal environment. The association of prenatal socioeconomic adversity and placental HSD11B2 methylation has not been examined. Following a developmental origins of disease framework, prenatal socioeconomic adversity may alter fetal response to the postnatal environment through functional epigenetic alterations in the placenta. Therefore, we hypothesized that prenatal socioeconomic adversity would be associated with less HSD11B2 methylation.Methods and FindingsWe examined the association between DNA methylation of the HSD11B2 promoter region in the placenta of 444 healthy term newborn infants and several markers of prenatal socioeconomic adversity: maternal education, poverty, dwelling crowding, tobacco use and cumulative risk. We also examined whether such associations were sex-specific. We found that infants whose mothers experienced the greatest levels of socioeconomic adversity during pregnancy had the lowest extent of placental HSD11B2 methylation, particularly for males. Associations were maintained for maternal education when adjusting for confounders (p<0.05).ConclusionsPatterns of HSD11B2 methylation suggest that environmental cues transmitted from the mother during gestation may program the developing fetus’s response to an adverse postnatal environment, potentially via less exposure to cortisol during development. Less methylation of placental HSD11B2 may therefore be adaptive and promote the effective management of stress associated with social adversity in a postnatal environment.

The recent introduction of the European green crab Carcinus maenas and Asian shore crab Hemigrapsus sanguineus to the west and east coasts of North America, respectively, presents a unique opportunity for investigation into competitive dynamics among intertidal crabs. Juvenile C. maenas utilize rocks, shell, and other cover, and their arrival on the west coast places them in potential competition for these resources with an abundant native grapsid, H. oregonensis. Similarly, H. sanguineus use intertidal shelter on the east coast, thus placing C. maenas in possible competition with grapsids both as an invader on the west coast and as 'resident' on the east coast, having been established there for more than 150 yr. Field sampling and laboratory experiments testing competition for space between C. maenas and Hemigrapsus spp. of equal carapace width were conducted on both coasts, as were videotaped feeding trials to examine and quantify agonistic interactions between species. When competing for food (a single damaged, anchored bivalve), C. maenas dominated over H. oregonensis, while H. sanguineus were overwhelmingly dominant over C. maenas. Within-quadrat, stratified sampling of rocks and sand revealed striking differences in habitat utilization by C. maenas living in the presence or absence of Hemigrapsus. Only ~20% of juvenile C. maenas occurred under rocks in areas occupied by either Hemigrapsus species, while north of the present distribution of H. sanguineus (in Maine) > 97% of the C. maenas were found beneath rocks. This pattern was reflected in laboratory trials as well, where both species of Hemigrapsus consistently dominated in contests for shelter. Given the importance of intertidal cover for small crabs, such competitive interactions will likely affect patterns of habitat use by C. maenas on the east coast and may have important implications for the ultimate distribution and impact of this species in the northeastern Pacific.