University of Nebraska–Lincoln

About: University of Nebraska–Lincoln is a education organization based out in Lincoln, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 28059 authors who have published 61544 publications receiving 2139104 citations. The organization is also known as: Nebraska & UNL.

Soybean response to water : A QTL analysis of drought tolerance

Abstract: Soybean [Glycine max (L.) Merr.] yield, when regressed on water needed to replenish 0 to 100% seasonal evapotranspiration (ET), generates an estimate of season-specific water-use efficiency (WUE). The impact of unpredictable water deficits might be lessened if high-yielding genotypes had a smaller beta. Our objective was to determine the genetic basis of beta and carbon isotope discrimination (CID), a theorized indicator of transpiration efficiency (TE). A Minsoy' Noir I' population of 236 recombinant inbred lines (RILs), genotyped at 665 loci, was evaluated in six water treatements (100, 80, 60, 40, 20, and 0% ET) for 2 yr. Water stress was mild in 1994, but high temperatures and no rainfall in 1995 led to a drought so severe that the 100% ET treatment required 41 cm of irrigation. The 1995 yield-to-water regression was highly linear (28 kg ha -1 cm -1 ), Genotype × water (G × W) interaction was due to genotypic heterogeneity in beta. The CH) vs. beta correlation was low (r = 0.26), so selection for better leaf TE may not improve crop WUE, Selection of low beta (less sensitivity to drought) will be difficult, given the yield beta vs. yield correlation (r = 0.71). The major quantitative trait loci (QTL) for yield beta, yield, and CID were coincident with maturity and/or determinancy QTLs. except for a CID QTL in linkage group U09-C2. but it had no effect on beta. Genetic improvement of soybean yield performance under drought would be better achieved by coupling a high-yield grand mean with a high- (not low-) yield beta.

Method for volumetric tissue ablation

Abstract: A volumetric tissue ablation apparatus includes a probe having a plurality of wires journaled through a catheter with a proximal end connected to the active terminal of a generator and a distal end projecting from a distal end of the catheter. The probe wire distal ends are arranged in an array with the distal ends located generally radially and uniformly spaced-apart from the catheter distal end. A conductor connected to the return terminal of the generator is located relative to the probe wire array to form a closed electrical circuit through tissue to be ablated. Preferably, the probe wire array includes 10 wires, each formed in an arch from the catheter distal end. The conductor can be either a conventional ground plate upon which the tissue is supported, or a conductor wire extending through the probe and electrically insulated from the probe wires.

Persons as Contexts: Evaluating Between-Person and Within-Person Effects in Longitudinal Analysis

Abstract: Relationships among multiple variables over time are of interest in many developmental areas and are frequently examined using time-varying predictors in multilevel models. Yet an incomplete specification of time-varying predictors will usually result in biased model effects. Specifically, the impact of constant, between-person sources of variation must be differentiated from the impact of time-specific, within-person sources of variation - that is, persons should be modeled as contexts. The current didactic article expands upon previous work to address why and how to model persons as contexts in longitudinal analysis. An electronic appendix of syntax for estimating these models is also provided.