Reducing αENaC expression in the kidney connecting tubule induces pseudohypoaldosteronism type 1 symptoms during K+ loading.

Genetic inactivation of the epithelial Na(+) channel α-subunit (αENaC) in the renal collecting duct (CD) does not interfere with Na(+) and K(+) homeostasis in mice. However, inactivation in the CD and a part of the connecting tubule (CNT) induces autosomal recessive pseudohypoaldosteronism type 1 (PHA-1) symptoms in subjects already on a standard diet. In the present study, we further examined the importance of αENaC in the CNT. Knockout mice with αENaC deleted primarily in a part of the CNT (CNT-KO) were generated using Scnn1a(lox/lox) mice and Atp6v1b1::Cre mice. With a standard diet, plasma Na(+) concentration ([Na(+)]) and [K(+)], and urine Na(+) and K(+) output were unaffected. Seven days of Na(+) restriction (0.01% Na(+)) led to a higher urine Na(+) output only on days 3-5, and after 7 days plasma [Na(+)] and [K(+)] were unaffected. In contrast, the CNT-KO mice were highly susceptible to a 2-day 5% K(+) diet and showed lower food intake and relative body weight, lower plasma [Na(+)], higher fractional excretion (FE) of Na(+), higher plasma [K(+)], and lower FE of K(+). The higher FE of Na(+) coincided with lower abundance and phosphorylation of the Na(+)-Cl(-) cotransporter. In conclusion, reducing ENaC expression in the CNT induces clear PHA-1 symptoms during high dietary K(+) loading

Cash Wheat in a Wheat-Ryegrass Grazing System.

8 p

The Strong CP Problem and Axions

I describe how the QCD vacuum structure, necessary to resolve the $U(1)_A$ problem, predicts the presence of a P, T and CP violating term proportional to the vacuum angle $\bar{\theta}$. To agree with experimental bounds, however, this parameter must be very small $(\bar{\theta} \leq 10^{-9}$). After briefly discussing some possible other solutions to this, so-called, strong CP problem, I concentrate on the chiral solution proposed by Peccei and Quinn which has associated with it a light pseudoscalar particle, the axion. I discuss in detail the properties and dynamics of axions, focusing particularly on invisible axion models where axions are very light, very weakly coupled and very long-lived. Astrophysical and cosmological bounds on invisible axions are also briefly touched upon.Comment: 14 pages, to appear in the Lecture Notes in Physics volume on Axions, (Springer Verlag

Threadleaf Groundsel and Forage Response to Herbicides in the Davis Mountains.

12 p

Recent results on nucleon sigma terms in lattice QCD

It has proven a significant challenge to experiment and phenomenology to extract precise values of the nucleon sigma terms. This difficulty opens the window for lattice QCD simulations to lead the field in resolving this aspect of nucleon structure. Here we report on recent advances in the extraction of nucleon sigma terms in lattice QCD. In particular, the strangeness component is now being resolved to a precision that far surpasses best phenomenological estimates.Comment: 6 pages, 1 figure; prepared for Proc. 4th Int Symposium on Symmetries in Subatomic Physics (SSP2009), Taipei, Taiwan, June 2-5 200

Rotational Invariance and the Theory of Directed Polymer Nematics

The consequences of rotational invariance in a recent theory of fluctuations in dilute polymer nematics are explored. A correct rotationally invariant free energy insures that anomalous couplings are not generated in a one-loop renormalization group calculation.Comment: 4 Pages, latex file (requires REVTEX 3.0), two postscript figures (attached), IASSNS-HEP-93/2

Reflections on the Strong CP Problem

I discuss how anomalies affect classical symmetries and how, in turn, the non-trivial nature of the gauge theory vacuum makes these quantum corrections troublesome. Although no solution seems in sight for the cosmological constant problem, I examine three possible approaches to the strong CP problem involving vacuum dynamics, an additional chiral symmetry, and the possibility of spontaneous CP or P breaking. All of these "solutions" have their own problems and suggest that, at a deep level, we do not understand the nature of CP violation. Nevertheless, it remains extremely important to search for experimental signals predicted by these theoretical "solutions", like invisible axions.Comment: 11 pages, Latex fil

Summary Talk at the 3rd KEK Topical Conference on CP Violation

A summary of the contributions to this topical conference is presented. The topics discussed ranged from detailing what we know about CP violation, to what we hope to learn in the future, to still unsolved mysteries in the subject.Comment: 12 pages, UCLA/TEP/16; figures will be FAXed on request by e-mailing [email protected]

Numerical Portrait of a Relativistic Thin Film BCS Superfluid

We present results of numerical simulations of the 2+1d Nambu - Jona-Lasinio model with a non-zero baryon chemical potential mu including the effects of a diquark source term. Diquark condensates, susceptibilities and masses are measured as functions of source strength j. The results suggest that diquark condensation does not take place in the high density phase mu>mu_c, but rather that the condensate scales non-analytically with j implying a line of critical points and long range phase coherence. Analogies are drawn with the low temperature phase of the 2d XY model. The spectrum of the spin-1/2 sector is also studied yielding the quasiparticle dispersion relation. There is no evidence for a non-zero gap; rather the results are characteristic of a normal Fermi liquid with Fermi velocity less than that of light. We conclude that the high density phase of the model describes a relativistic gapless thin film BCS superfluid.Comment: 37 pages, 16 figure

Theta angle versus CP violation in the leptonic sector

Assuming that the axion mechanism of solving the strong CP problem does not exist and the vanishing of theta at tree level is achieved by some model-building means, we study the naturalness of having large CP-violating sources in the leptonic sector. We consider the radiative mechanisms which transfer a possibly large CP-violating phase in the leptonic sector to the theta parameter. It is found that large theta cannot be induced in the models with one Higgs doublet as at least three loops are required in this case. In the models with two or more Higgs doublets the dominant source of theta is the phases in the scalar potential, induced by CP violation in leptonic sector. Thus, in the MSSM framework the imaginary part of the trilinear soft-breaking parameter A_l generates the corrections to the theta angle already at one loop. These corrections are large, excluding the possibility of large phases, unless the universality in the slepton sector is strongly violated.Comment: 5 pages, 2 figure