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Ergovaline has been proposed as a toxic component of endophyte-infected tall fescue. As many of the symptoms of fescue toxicosis are a result of compromised circulation, the objective of this study was to examine the vasoconstrictive potentials of ergovaline and a more documented ergopeptine, ergotamine, using a bovine, lateral (cranial branch) saphenous vein bioassay. Segments of the cranial branch of the lateral saphenous vein (2 to 3 cm) were collected from healthy, mixed breed cattle (n = 12 and n = 5 for the ergovaline and ergotamine experiments, respectively) at local abattoirs. The veins were trimmed of excess fat and connective tissue, sliced into 2- to 3-mm cross sections, and suspended in a myograph chamber containing 5 mL of a modified Krebs-Henseleit, oxygenated buffer (95% [O.sub.2] + 5% C[O.sub.2]; pH = 7.4; 37 [degrees] C). The tissue was allowed to equilibrate at I g of tension for 90 min before of the addition of treatments. Increasing doses of ergovaline (1 x [10.sub.-11] to 1 x [10.sub.-4] M) or ergotamine (1 x [10.sub.-11] to 1 x [10.sub.-5] M) were administered every 15 min after buffer replacement. Contractile response data were normalized to a percentage induced by a reference dose of norepinephrine (1 x [10.sub.-4] M). Contractile responses of saphenous veins were similar for ergovaline and ergotamine. Initial contractile responses began at 1 x [10.sub.-8] M for both ergovaline and ergotamine (4.4 [+ or -] 0.8% and 5.6 [+ or -] 1.1%, respectively). Vascular tension continued to increase as the alkaloid concentrations increased (maximums: 43.7 [+ or -] 7.1% at 1 x [10.sub.-5] M ergotamine; 69.6 [+ or -] 5.3% at 1 x [10.sub.-4] M ergovaline). Interestingly, ergovaline-induced contractions (1 x [10.sub.-4] M) were not reversed by repeated buffer replacement over a 105-min period. As previously shown with ergotamine, these results confirm that ergovaline is a potent vasoconstrictor. The resistance of an ergovaline-induced contraction to relaxation over an extended period of time suggests a potential for bioaccumulation of this ergopeptine alkaloid and may aid in understanding its toxicity within the animal. Key words: alkaloid, bovine, ergovaline, ergotamine, fescue, vasoconstriction

Vasoconstriction has been associated with several symptoms of fescue toxicosis thought to be alkaloid induced. Lysergic acid, an ergot alkaloid, has been proposed as a toxic component of endophyte-infected tall fescue. The objective of this study was to examine the vasoconstrictive potential of D-lysergic acid using a bovine lateral (cranial branch) saphenous vein bioassay. Before testing lysergic acid, validation of the bovine lateral saphenous vein bioassay for use with a multimyograph apparatus was conducted using a doseresponse to norepinephrine to evaluate the effects of limb of origin (right vs. left) and overnight storage on vessel contractile response. Segments (2 to 3 cm) of the cranial branch of the lateral saphenous vein were collected from healthy mixed breed cattle (n = 12 and n = 7 for the lysergic acid and norepinephrine experiments, respectively) at local abattoirs. Tissue was placed in modified Krebs-Henseleit, oxygenated buffer and kept on ice or stored at 2 to 8[degrees]C until used. Veins were trimmed of excess fat and connective tissue, sliced into 2- to 3-mm sections, and suspended in a myograph chamber containing 5 mL of oxygenated Krebs-Henseleit buffer (95% [O.sub.2], 5% C[O.sub.2]; pH = 7.4; 37[degrees]C). Tissue was allowed to equilibrate at 1 g of tension for 90 min before initiation of treatment additions. Increasing doses of norepinephrine (1 x [10.sup.-8] to 5 x [10.sup.-4] M) or lysergic acid (1 x [10.sup.-11] to 1 x [10.sup.-4] M) were administered every 15 min after buffer replacement. Data were normalized as a percentage of the contractile response induced by a reference dose of norepinephrine. Veins from both left and right limbs demonstrated contractions in a dose-dependent manner (P < 0.01) but did not differ between limbs. There were no differences in dose-response to norepinephrine between tissue tested the day of dissection and tissue tested 24 h later. Exposure of vein segments to increasing concentrations of lysergic acid did not result in an appreciable contractile response until the addition of 1 x [10.sup.-4] M lysergic acid (15.6 [+ or -] 2.3% of the 1 x [10.sup.-4] M norepinephrine response). These data indicate that only highly elevated concentrations of lysergic acid result in vasoconstriction. Thus, in relation to the symptoms associated with vasoconstriction, lysergic acid may only play a minor role in the manifestation of fescue toxicosis. Key words: alkaloid, bovine, fescue, lysergic acid, vasoconstriction

This paper describes the design and testing of a catalytically stabilized pilot burner for current and advanced Dry Low N[O.sub.x] (DLN) gas turbine combustors. In this paper, application of the catalytic pilot technology to industrial engines is described using Solar Turbines' Taurus 70 engine. The objective of the work described is to develop the catalytic pilot technology and document the emission benefits of catalytic pilot technology when compared to higher, N[O.sub.x] producing pilots. The catalytic pilot was designed to replace the existing pilot in the existing DLN injector without major modification to the injector. During high-pressure testing, the catalytic pilot showed no incidence of flashback or autoignition while operating over wide range of combustion temperatures. The catalytic reactor lit off at a temperature of approximately 598 K (325[degeres]C/ 617[degres]F) and operated at simulated 100% and 50% load conditions without a preburner. At high pressure, the maximum catalyst surface temperature was similar to that observed during atmospheric pressure testing and considerably lower than the surface temperature expected in lean-burn catalytic devices. In single-injector rig testing, the integrated assembly of the catalytic pilot and Taurus 70 injector demonstrated N[O.sub.x] and CO emission less than 5 ppm @ 15% [O.sub.2] for 100% and 50% load conditions along with low acoustics. The results demonstrate that a catalytic pilot burner replacing a diffusion flame or partially premixed pilot in an otherwise DLN combustor can enable operation at conditions with substantially reduced N[O.sub.x] emissions. [DOI: 10.1115/1.1586313]

A study was conducted on substrate-dependent nucleation of plasma-deposited microcrystalline silicon that were atomic force microscopy-grown on glass and silicon substrates. Reflective high energy electron diffraction analysis shows that the films grown on microcrystalline silicon exhibited amorphous structures during the initial stages of growth. The nucleation differences of the films verify the mechanisms and limitations of plasma enhanced selective deposition of microcrystalline silicon.

Many species that inhabit seasonally ponded wetlands also rely on surrounding upland habitats and nearby aquatic ecosystems for resources to support life stages and to maintain viable populations. Understanding biological connectivity among these habitats is critical to ensure that landscapes are protected at appropriate scales to conserve species and ecosystem function. Biological connectivity occurs across a range of spatial and temporal scales. For example, at annual time scales many organisms move between seasonal wetlands and adjacent terrestrial habitats as they undergo life‐stage transitions; at generational time scales, individuals may disperse among nearby wetlands; and at multigenerational scales, there can be gene flow across large portions of a species' range. The scale of biological connectivity may also vary among species. Larger bodied or more vagile species can connect a matrix of seasonally ponded wetlands, streams, lakes, and surrounding terrestrial habitats on a seasonal or annual basis. Measuring biological connectivity at different spatial and temporal scales remains a challenge. Here we review environmental and biological factors that drive biological connectivity, discuss implications of biological connectivity for animal populations and ecosystem processes, and provide examples illustrating the range of spatial and temporal scales across which biological connectivity occurs in seasonal wetlands. Research Impact Statement: Seasonal wetlands are connected biologically to surrounding ecosystems through the movements of animals. This connectivity is critical to species conservation and ecosystem functioning. [ABSTRACT FROM AUTHOR]

The Bismarck Archipelago has been identified by archaeologists as the homeland of the Lapita people, the first settlers of remote Oceania, yet little genetic research has been undertaken in these islands to test hypotheses of migration to Polynesia. We have analyzed a total of 152 samples from Austronesian and non-Austronesian speaking populations of New Britain sequenced for over 1000 base pairs of HVS 1 and 2, and we are currently sequencing additional samples from New Ireland, as well as from Papua New Guinea, Ontong Java, and Bougainville. Of the 15 haplogroups found in Melanesia by the Merriwether lab and from the literature, 11 have been recognized in the Bismarcks. Preliminary results indicate potential gene flow between Austronesian and non-Austronesian speakers in New Britain, but this finding is not yet quantified. However, a transition at position 16468 of the Anderson, et al. sequence was identified which is common in New Britain populations and observed in remote Oceania but is absent from all but one New Guinea sample and not found in any sequences from Southeast Asia. This could provide a novel way to assess how much indigenous Melanesians in the Bismarcks of elsewhere contributed to the Lapita gene pool.