Developmental profile and regulation of brain estrogen synthesis by aromatase

Aromatase cytochrome P450 enzyme catalyzes the formation of estrogen from androgen in distinct regions of the vertebrate brain. During neural development, local estrogen synthesis is required for the sexual differentiation of male brain characteristics and the differentiation of neural circuits Involved in sex-specific behaviors and neuroendocrine functions. A common phenomenon in all species studied so far is that the male brain displays much higher and brain region-specific aromatase expression during distinct periods of brain development than the female one. An important question arising from these findings is which factor(s) play a role in regulating estrogen formation in a sex- and brain region-specific fashion. Among the factors investigated, androgens have been found to be the most powerful regulators of brain aromatase. In vitro experiments using primary cell cultures of embryonic mouse brains showed that sex differences in aromatase activity in hypothalamic cells develop, at first, independently of gonadal steroids. Later during embryonic development, aromatase expression is regulated in a region- and sex-specific way by circulating androgens. Hypothalamic aromatase neurons are most sensitive to androgen exposure whereas cortical and midbrain ones are insensitive. Moreover, androgens affect morphological maturation of aromatase-immunoreactive cells by stimulating neurite outgrowth and dendritic arborization. These findings suggest that androgens function as major morphogenetic factors during the differentiation of the mammalian hypothalamic aromatase system. During late embryonic development and perinatally, androgen levels differ between sexes, being significantly higher in males. This time period corresponds exactly to the developmental stage when aromatase activities are highest in the male hypothalamus. It seems plausible therefore that higher androgen concentrations in the male circulation during ontogenesis are causally connected with the observed sex differences in hypothalamic aromatase activity.Biomedical Reviews 1997; 7: 41-50

A modelling evaluation of electromagnetic fields emitted by buried subsea power cables and encountered by marine animals : considerations for marine renewable energy development

Part of this work was supported by the Bureau of Ocean Energy Management (contract number M14PC00009).The expanding marine renewable energy industry will increase the prevalence of electromagnetic fields (EMFs) from power cables in coastal waters. Assessments of environmental impacts are required within licensing/permitting processes and increased prevalence of cables will increase questions concerning EMF emissions and potential cumulative impacts. It is presumed that protecting a cable by burial, may also mitigate EMF emissions and potential impacts on species. Focussing on a bundled high voltage direct current (HVDC) transmission cable, we use computational and interpretive models to explore the influence of cable properties and burial depth on the DC magnetic field (DC-MF) potentially encountered by receptive species. Greater cable pair separation increased the deviations from the geomagnetic field and while deeper burial reduced the deviations, the DC-MF was present at intensities perceivable by receptive species. An animal moving along a cable route may be exposed to variable EMFs due to varied burial depth and that combined with an animal’s position in the water column determines the distance from source and EMF exposure. Modelling contextually realistic scenarios would improve assessments of potential effects. We suggest developers and cable industries make cable properties and energy transmission data available, enabling realistic modelling and environmental assessment supporting future developments.PostprintPeer reviewe

Transmission of α-synucleinopathy from olfactory structures deep into the temporal lobe

Supplemental files to the publication Transmission of α-synucleinopathy from olfactory structures deep into the temporal lobe : Supplemental information (PDF): Materials and methods, tables, and supplemental figures S1-S8 (all supplemental figures are mentioned in the main text). Two mp4 movie files showing perinuclear localization of pSer129 signal (red) around NeuN+ nuclei (green). One movie shows a rotating cell and in the other video, the red pSer129 signal is peeled away to reveal the underlying green NeuN+ nucleus. Four high resolution figures (TIFF files)

Overcoming challenges on an international project to advance systems engineering

The Body of Knowledge and Curriculum to Advance Systems Engineering (BKCASE) project's dual product development cycle spanned a three‐year period from the September 2009 to December, 2012. During this timeframe, BKCASE authors met quarterly at various locations, primarily in various regions of the United States, but also in Stockholm, Sweden; Toulouse, France; London, England; and Rome, Italy (BKCASE, 2009–2019). The team successfully worked through challenges and differences to produce The Guide to the Systems Engineering Body of Knowledge (SEBoK) wiki and a Graduate Reference Curriculum for Systems Engineering (GRCSE) publication. This article is a collection of personal stories from the team members that focus on overcoming obstacles to successfully produce the final published products

Pennsylvania Folklife Vol. 43, No. 3

• The Old Order Amish • Amish Quilts: Creativity Supported by Rules and Traditions • Conflict: A Mainspring of Amish Society • Occupational Opportunities for Old Order Amish Women • The Amish Taboo on Photography: Its Historical and Social Significance • Our Changing Amish Church District • Images of the Amish on Stage and Film • Amish Gardens: A Symbol of Identity • The Myth of the Ideal Folk Society Versus the Reality of Amish Lifehttps://digitalcommons.ursinus.edu/pafolklifemag/1140/thumbnail.jp

Pest population dynamics are related to a continental overwintering gradient

Overwintering success is an important determinant of arthropod populations that must be considered as climate change continues to influence the spatiotemporal population dynamics of agricultural pests. Using a long-term monitoring database and biologically relevant overwintering zones, we modeled the annual and seasonal population dynamics of a common pest, Helicoverpa zea (Boddie), based on three overwintering suitability zones throughout North America using four decades of soil temperatures: the southern range (able to persist through winter), transitional zone (uncertain overwintering survivorship), and northern limits (unable to survive winter). Our model indicates H. zea population dynamics are hierarchically structured with continental-level effects that are partitioned into three geographic zones. Seasonal populations were initially detected in the southern range, where they experienced multiple large population peaks. All three zones experienced a final peak between late July (southern range) and mid-August to mid-September (transitional zone and northern limits). The southern range expanded by 3% since 1981 and is projected to increase by twofold by 2099 but the areas of other zones are expected to decrease in the future. These changes suggest larger populations may persist at higher latitudes in the future due to reduced low-temperature lethal events during winter. Because H. zea is a highly migratory pest, predicting when populations accumulate in one region can inform synchronous or lagged population development in other regions. We show the value of combining long-term datasets, remotely sensed data, and laboratory findings to inform forecasting of insect pests

Recalibrating single-study effect sizes using hierarchical Bayesian models

INTRODUCTION: There are growing concerns about commonly inflated effect sizes in small neuroimaging studies, yet no study has addressed recalibrating effect size estimates for small samples. To tackle this issue, we propose a hierarchical Bayesian model to adjust the magnitude of single-study effect sizes while incorporating a tailored estimation of sampling variance.METHODS: We estimated the effect sizes of case-control differences on brain structural features between individuals who were dependent on alcohol, nicotine, cocaine, methamphetamine, or cannabis and non-dependent participants for 21 individual studies (Total cases: 903; Total controls: 996). Then, the study-specific effect sizes were modeled using a hierarchical Bayesian approach in which the parameters of the study-specific effect size distributions were sampled from a higher-order overarching distribution. The posterior distribution of the overarching and study-specific parameters was approximated using the Gibbs sampling method.RESULTS: The results showed shrinkage of the posterior distribution of the study-specific estimates toward the overarching estimates given the original effect sizes observed in individual studies. Differences between the original effect sizes (i.e., Cohen's d) and the point estimate of the posterior distribution ranged from 0 to 0.97. The magnitude of adjustment was negatively correlated with the sample size (r = -0.27, p &lt; 0.001) and positively correlated with empirically estimated sampling variance (r = 0.40, p &lt; 0.001), suggesting studies with smaller samples and larger sampling variance tended to have greater adjustments. DISCUSSION: Our findings demonstrate the utility of the hierarchical Bayesian model in recalibrating single-study effect sizes using information from similar studies. This suggests that Bayesian utilization of existing knowledge can be an effective alternative approach to improve the effect size estimation in individual studies, particularly for those with smaller samples.</p