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Variation in early life maternal care predicts later long range frontal cortex synapse development in mice.
Empirical and theoretical work suggests that early postnatal experience may inform later developing synaptic connectivity to adapt the brain to its environment. We hypothesized that early maternal experience may program the development of synaptic density on long range frontal cortex projections. To test this idea, we used maternal separation (MS) to generate environmental variability and examined how MS affected 1) maternal care and 2) synapse density on virally-labeled long range axons of offspring reared in MS or control conditions. We found that MS and variation in maternal care predicted bouton density on dorsal frontal cortex axons that terminated in the basolateral amygdala (BLA) and dorsomedial striatum (DMS) with more, fragmented care associated with higher density. The effects of maternal care on these distinct axonal projections of the frontal cortex were manifest at different ages. Maternal care measures were correlated with frontal cortex → BLA bouton density at mid-adolescence postnatal (P) day 35 and frontal cortex → DMS bouton density in adulthood (P85). Meanwhile, we found no evidence that MS or maternal care affected bouton density on ascending orbitofrontal cortex (OFC) or BLA axons that terminated in the dorsal frontal cortices. Our data show that variation in early experience can alter development in a circuit-specific and age-dependent manner that may be relevant to understanding the effects of early life adversity
Biological Characteristics and Fishery Assessment of Alaska Plaice, Pleuronectes quadrituberculatus, in the Eastern Bering Sea
Alaska plaice, Pleuronectes quadrituberculatus, is one of the major flatfishes in the eastern Bering Sea ecosystem
and is most highly concentrated in the shallow continental shelf of the eastern Bering Sea. Annual commercial catches have ranged from less than 1,000 metric tons (t) in 1963 to 62,000 t in 1988. Alaska plaice is a relatively large flatfish averaging about 32 cm in length and 390 g in weight in commercial catches. They are distributed from
nearshore waters to a depth of about 100 m in the eastern Bering Sea during summer, but move to deeper continental shelf waters in winter to escape sea ice and cold water
temperatures. Being a long-lived species (>30 years), they have a relatively low natural mortality rate estimated at 0.20. Maturing at about age 7, Alaska plaice spawn from April through June on hard sandy substrates of the shelf region, primarily around the 100 m isobath. Prey items
primarily include polychaetes and other marine worms. In comparison with other flatfish, Alaska plaice and rock sole, Pleuronectes bilineatus, have similar diets but different habitat preferences with separate areas of peak population density which may minimize interspecific competition. Yellowfin sole, Pleuronectes asper, while sharing similar habitat, differs from these two species
because of the variety of prey items in its diet. Competition for food resources among the three species appears to be low. The resource has experienced light exploitation since 1963 and is currently in good condition. Based on the results of demersal trawl surveys and age-structured analyses, the exploitable biomass increased
from 1971 through the mid-1980’s before decreasing to the 1997 level of 500,000 t. The recommended 1998 harvest level, Allowable Biological Catch, was calculated from the Baranov catch equation based on the FMSY harvest level and the projected 1997 biomass, resulting in a commercial
harvest of 69,000 t, or about 16% of the estimated exploitable biomass
Spatially separated polar samples of the cis and trans conformers of 3-fluorophenol
We demonstrate the spatial separation of the cis- and trans-conformers of
3-fluorophenol in the gas phase based on their distinct electric dipole
moments. For both conformers we create very polar samples of their
lowest-energy rotational quantum states. A >95 % pure beam of
trans-3-fluorophenol and a >90 % pure beam of the lowest-energy rotational
states of the less polar cis-3-fluorophenol were obtained for helium and neon
supersonic expansions, respectively. This is the first demonstration of the
spatial separation of the lowest-energy rotational states of the least polar
conformer, which is necessary for strong alignment and orientation of all
individual conformers.Comment: 5 pages, 5 figure
Mental Health And The Role Of The States
Researchers from the State Health Care Spending Project -- a collaboration between The Pew Charitable Trusts and the John D. and Catherine T. MacArthur Foundation -- sought to better understand the country's mental health challenges and, in particular, the states' role in addressing them. The project found that:In 2013, approximately 44 million adults -- 18.5 percent of the population 18 and older -- were classified as having a mental illness. Of these, 10 million had a serious mental illness. The rate of serious mental illness varied from state to state.In 2009, the most recent year for which national mental health data are available, 22 billion (15 percent) in 2009. This total does not include state and local Medicaid expenditures. Counting those contributions brings total state and local spending up to $35.5 billion (24 percent).This report is intended to help federal, state, and local policymakers working to address the country's mental health challenges to better understand their prevalence, treatment, and funding trends
Groups with torsion, bordism and rho-invariants
Let G be a discrete group, and let M be a closed spin manifold of dimension
m>3 with pi_1(M)=G. We assume that M admits a Riemannian metric of positive
scalar curvature. We discuss how to use the L2-rho invariant and the
delocalized eta invariant associated to the Dirac operator on M in order to get
information about the space of metrics with positive scalar curvatur1e.
In particular we prove that, if G contains torsion and M is congruent 3 mod 4
then M admits infinitely many different bordism classes of metrics with
positive scalar curvature. We show that this is true even up to diffeomorphism.
If G has certain special properties then we obtain more refined information
about the ``size'' of the space of metric of positive scalar curvature, and
these results also apply if the dimension is congruent to 1 mod 4. For example,
if G contains a central element of odd order, then the moduli space of metrics
of positive scalar curvature has infinitely many components, if it is not
empty.
Some of our invariants are the delocalized eta-invariants introduced by John
Lott. These invariants are defined by certain integrals whose convergence is
not clear in general, and we show, in effect, that examples exist where this
integral definitely does not converge, thus answering a question of Lott.
We also discuss the possible values of the rho invariants of the Dirac
operator and show that there are certain global restrictions (provided the
scalar curvature is positive).Comment: 21 pages; comma in metadata (author field) added. final version to
appear in Pacific Journal of Mathematic
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