New Record for the Endangered Crawling Water Beetle, \u3ci\u3eBrychius Hungerfordi\u3c/i\u3e (Coleoptera: Haliplidae) in Michigan Including Water Chemistry Data

We report the discovery of the Federally endangered crawling water beetle, Brychius hungerfordi Spangler, in a new watershed in the northern lower peninsula of MIchigan. The site was found on the Carp River, a lake draining first-order stream. Nine water chemistry parameters were measured from three known locations of B. hungerfordi and from three sites where no B. hungerfordi have been found. Water from sites with known populations of adult beetles showed low soluble reactive phosphorus, but were similar to other similar rivers in northern Michigan

Determining the Price-Responsiveness of Demands for Irrigation Water Deliveries versus Consumptive Use

A water-crop simulation/mathematical programming model of irrigation water demand in northeastern Colorado is formulated to develop an original concept of derived demand for consumptive use of water. Conventional demand functions for water deliveries are also developed, and the effect of hypothetical price increases on both consumption and delivery are illustrated. Findings indicate that demand elasticity estimates are quite sensitive to model specification, and consumptive use demand tends to be significantly less price-responsive than delivery demand. Thus price incentives are likely to have only limited impacts on basin-wide water consumption and would not make much additional water available for emerging demands.crop simulation, irrigation, mathematical programming, water conservation, water-demand elasticities, water policy, Demand and Price Analysis, Resource /Energy Economics and Policy,

OMP Peptides Activate the DegS Stress-Sensor Protease by a Relief of Inhibition Mechanism

In the E. coli periplasm, C-terminal peptides of misfolded outer-membrane porins (OMPs) bind to the PDZ domains of the trimeric DegS protease, triggering cleavage of a transmembrane regulator and transcriptional activation of stress genes. We show that an active-site DegS mutation partially bypasses the requirement for peptide activation and acts synergistically with mutations that disrupt contacts between the protease and PDZ domains. Biochemical results support an allosteric model, in which these mutations, active-site modification, and peptide/substrate binding act in concert to stabilize proteolytically active DegS. Cocrystal structures of DegS in complex with different OMP peptides reveal activation of the protease domain with varied conformations of the PDZ domain and without specific contacts from the bound OMP peptide. Taken together, these results indicate that the binding of OMP peptides activates proteolysis principally by relieving inhibitory contacts between the PDZ domain and the protease domain of DegS.United States. Dept. of Energy (Office of Basic Energy Sciences, contract DE-AC02-06CH11357))National Institutes of Health (U.S.) (NIH-NCRR award RR-15301)National Institutes of Health (U.S.) (NIH postdoctoral fellowship (F32AI-074245-01A1))National Institutes of Health (U.S.) (NIH grant AI-16892

Drainage Issues in the Atlantic Canada Offshore Petroleum Industry

In this article, the authors examine the issue of drainage in the Atlantic Canada offshore. The offshore statutory regimes for production of oil and gas, together with the common law, are analyzed for their approaches to dealing with drainage issues. In addition, the law of drainage in Alberta is comprehensively reviewed to provide some guidance as to how the law of drainage may develop in Atlantic Canada

Filamentary Accretion Flows in the Embedded Serpens South Protocluster

One puzzle in understanding how stars form in clusters is the source of mass -- is all of the mass in place before the first stars are born, or is there an extended period when the cluster accretes material which can continuously fuel the star formation process? We use a multi-line spectral survey of the southern filament associated with the Serpens South embedded cluster-forming region in order to determine if mass is accreting from the filament onto the cluster, and whether the accretion rate is significant. Our analysis suggests that material is flowing along the filament's long axis at a rate of ~30Msol/Myr (inferred from the N2H+ velocity gradient along the filament), and radially contracting onto the filament at ~130Msol/Myr (inferred from HNC self-absorption). These accretion rates are sufficient to supply mass to the central cluster at a similar rate to the current star formation rate in the cluster. Filamentary accretion flows may therefore be very important in the ongoing evolution of this cluster.Comment: 19 pages, 8 figures, 2 tables; accepted for publication in Ap