Substance P regulates puberty onset and fertility in the female mouse

Puberty is a tightly regulated process that leads to reproductive capacity. Kiss1 neurons are crucial in this process by stimulating GnRH, yet how Kiss1 neurons are regulated remains unknown. Substance P (SP), an important neuropeptide in pain perception, induces gonadotropin release in adult mice in a kisspeptin-dependent manner. Here, we assessed whether SP, through binding to its receptor NK1R (neurokinin 1 receptor), participates in the timing of puberty onset and fertility in the mouse. We observed that 1) selective NK1R agonists induce gonadotropin release in prepubertal females; 2) the expression of Tac1 (encoding SP) and Tacr1 (NK1R) in the arcuate nucleus is maximal before puberty, suggesting increased SP tone; 3) repeated exposure to NK1R agonists prepubertally advances puberty onset; and 4) female Tac1-/- mice display delayed puberty; moreover, 5) SP deficiency leads to subfertility in females, showing fewer corpora lutea and antral follicles and leading to decreased litter size. Thus, our findings support a role for SP in the stimulation of gonadotropins before puberty, acting via Kiss1 neurons to stimulate GnRH release, and its involvement in the attainment of full reproductive capabilities in female mice. Copyright © 2015 by the Endocrine Society

Localization via Automorphisms of the CARs. Local gauge invariance

The classical matter fields are sections of a vector bundle E with base manifold M. The space L^2(E) of square integrable matter fields w.r.t. a locally Lebesgue measure on M, has an important module action of C_b^\infty(M) on it. This module action defines restriction maps and encodes the local structure of the classical fields. For the quantum context, we show that this module action defines an automorphism group on the algebra A, of the canonical anticommutation relations on L^2(E), with which we can perform the analogous localization. That is, the net structure of the CAR, A, w.r.t. appropriate subsets of M can be obtained simply from the invariance algebras of appropriate subgroups. We also identify the quantum analogues of restriction maps. As a corollary, we prove a well-known "folk theorem," that the algebra A contains only trivial gauge invariant observables w.r.t. a local gauge group acting on E.Comment: 15 page

A lattice model for the kinetics of rupture of fluid bilayer membranes

We have constructed a model for the kinetics of rupture of membranes under tension, applying physical principles relevant to lipid bilayers held together by hydrophobic interactions. The membrane is characterized by the bulk compressibility (for expansion), the thickness of the hydrophobic part of the bilayer, the hydrophobicity and a parameter characterizing the tail rigidity of the lipids. The model is a lattice model which incorporates strain relaxation, and considers the nucleation of pores at constant area, constant temperature, and constant particle number. The particle number is conserved by allowing multiple occupancy of the sites. An equilibrium ``phase diagram'' is constructed as a function of temperature and strain with the total pore surface and distribution as the order parameters. A first order rupture line is found with increasing tension, and a continuous increase in proto-pore concentration with rising temperature till instability. The model explains current results on saturated and unsaturated PC lipid bilayers and thicker artificial bilayers made of diblock copolymers. Pore size distributions are presented for various values of area expansion and temperature, and the fractal dimension of the pore edge is evaluated.Comment: 15 pages, 8 figure

Extraplanar Dust in Spiral Galaxies: Tracing Outflows in the Disk-Halo Interface

There is now ample evidence that the interstellar thick disks of spiral galaxies are dusty. Although the majority of extraplanar gas in the first few kiloparsecs above the plane of a spiral galaxy is matter that has been expelled from the thin disk, the feedback-driven expulsion does not destroy dust grains altogether (and there is not yet any good measure suggesting it changes the dust-to-gas mass ratio). Direct optical imaging of a majority of edge-on spiral galaxies shows large numbers of dusty clouds populating the thick disk to heights z~2 kpc. These observations are likely revealing a cold, dense phase of the thick disk interstellar medium. New observations in the mid-infrared show emission from traditional grains and polycyclic aromatic hydrocarbons (PAHs) in the thick disks of spiral galaxies. PAHs are found to have large scale heights and to arise both in the dense dusty clouds traced through direct optical imaging and in the diffuse ionized gas. In this contribution, we briefly summarize these probes of dust in the thick disks of spiral galaxies. We also argue that not only can dust can be used to trace extraplanar material that has come from within the thick disk, but that its absence can be a marker for newly accreted matter from the circumgalactic or intergalactic medium. Thus, observations of dust can perhaps provide a quantitative measure of the importance of "outflow versus infall" in spiral galaxies.Comment: 8 pages; Invited review for the proceedings of "The Role of Disk-Halo Interaction in Galaxy Evolution: Outflow vs. Infall?" (Ed. M. de Avillez), in Espinho, Portugal, 18-22 August 2008 ; high resolution version at http://www.nd.edu/~jhowk/Papers/papers.html#conferenc

The complications of ‘hiring a hubby’: gender relations and the commoditisation of home maintenance in New Zealand

This paper examines the commoditization of traditionally male domestic tasks through interviews with handymen who own franchises in the company ‘Hire a Hubby’ in New Zealand and homeowners who have paid for home repair tasks to be done. Discussions of the commoditization of traditionally female tasks in the home have revealed the emotional conflicts of paying others to care as well as the exploitative and degrading conditions that often arise when work takes place behind closed doors. By examining the working conditions and relationships involved when traditionally male tasks are paid for, this paper raises important questions about the valuing of reproductive labour and the production of gendered identities. The paper argues that while working conditions and rates of pay for ‘hubbies’ are better than those for people undertaking commoditized forms of traditionally female domestic labour, the negotiation of this work is still complex and implicated in gendered relations and identities. Working on the home was described by interviewees as an expression of care for family and a performance of the ‘right’ way to be a ‘Kiwi bloke’ and a father. Paying others to do this labour can imply a failure in a duty of care and in the performance of masculinity

Grass burning under our feet: Indigenous enterprise development in a political economy of whiteness

In this article we discuss some of our findings from two research projects that explore opportunities for Indigenous enterprise development in remote locations in Northern and Central Australia. Based on a series of focus groups and in-depth interviews with Indigenous community leaders, Traditional Owners, government officials, Land Council officials and other stakeholders, we discuss barriers to economic development faced by Indigenous communities in remote regions. We argue that many of these barriers are the material effects of discursive practices of ‘whiteness’ in the political economy. We discuss the relationships between institutions and Indigenous communities that constitute the Indigenous political economy and argue that these relationships are informed by discursive practices of whiteness and colonial-capitalist relations of power. We conclude by discussing the implications of our findings for management learning and public policy

Acute cocoa flavanol supplementation improves muscle macro- and microvascular but not anabolic responses to amino acids in older men

The anabolic effects of nutrition on skeletal muscle may depend on adequate skeletal muscle perfusion, which is impaired in older people. Cocoa flavanols have been shown to improve flow-mediated dilation, an established measure of endothelial function. However, their effect on muscle microvascular blood flow is currently unknown. Therefore, the objective of this study was to explore links between the consumption of cocoa flavanols, muscle microvascular blood flow and muscle protein synthesis (MPS) in response to nutrition in older men. To achieve this objective leg blood flow (LBF), muscle microvascular blood volume (MBV) and MPS were measured under postabsorptive and postprandial (I.V glamin, dextrose to sustain glucose ~7.5 mmol·l-1) conditions in 20 older men. Ten of these men were studied with no cocoa flavanol intervention and a further 10 were studied with the addition of 350 mg of cocoa flavanols at the same time as nutrition began. Leg [femoral artery] blood flow was measured by Doppler ultrasound, muscle MBV by contrast-enhanced ultrasound (CEUS) using DefinityTM perflutren contrast agent and MPS using [1, 2-13C2] leucine tracer techniques. Our results show that although older individuals do not show an increase in LBF or MBV in response to feeding, these absent responses are apparent when cocoa flavanols are given acutely with nutrition. However this restoration in vascular responsiveness is not associated with improved MPS responses to nutrition. We conclude that acute cocoa flavanol supplementation improves muscle macro- and microvascular responses to nutrition, independently of modifying muscle protein anabolism

Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector

The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the MAJORANA Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.Comment: Submitted to NIMA Proceedings, SORMA XII. 9 pages, 4 figure

Global Search for New Physics with 2.0/fb at CDF

Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for "bumps" that could indicate resonant production of new particles; and the Sleuth procedure scans for data excesses at large summed transverse momentum. This combined global search for new physics in 2.0/fb of ppbar collisions at sqrt(s)=1.96 TeV reveals no indication of physics beyond the standard model.Comment: 8 pages, 7 figures. Final version which appeared in Physical Review D Rapid Communication