653 research outputs found
EPG-representations with small grid-size
In an EPG-representation of a graph each vertex is represented by a path
in the rectangular grid, and is an edge in if and only if the paths
representing an share a grid-edge. Requiring paths representing edges
to be x-monotone or, even stronger, both x- and y-monotone gives rise to three
natural variants of EPG-representations, one where edges have no monotonicity
requirements and two with the aforementioned monotonicity requirements. The
focus of this paper is understanding how small a grid can be achieved for such
EPG-representations with respect to various graph parameters.
We show that there are -edge graphs that require a grid of area
in any variant of EPG-representations. Similarly there are
pathwidth- graphs that require height and area in
any variant of EPG-representations. We prove a matching upper bound of
area for all pathwidth- graphs in the strongest model, the one where edges
are required to be both x- and y-monotone. Thus in this strongest model, the
result implies, for example, , and area bounds
for bounded pathwidth graphs, bounded treewidth graphs and all classes of
graphs that exclude a fixed minor, respectively. For the model with no
restrictions on the monotonicity of the edges, stronger results can be achieved
for some graph classes, for example an area bound for bounded treewidth
graphs and bound for graphs of bounded genus.Comment: Appears in the Proceedings of the 25th International Symposium on
Graph Drawing and Network Visualization (GD 2017
Evaluation of Wheat Middlings as a Supplement for Beef Cows Grazing Native Winter Range
Two winter grazing trials were conducted at the SDSU Cottonwood Research Station near Cottonwood, SD, to compare wheat middlings to soybean meal and corn-soybean meal supplements. In consecutive years, grazing trials from December to February were conducted using Simmental x Angus crossbred cows grazing two pastures with differing amounts of available forage and fed four supplemental treatments that were balanced to provide the following amounts of crude protein (Ib) and metabolizable energy (Mcal) per cow daily: 1) soybean meal .75 and 2.40, 2) low wheat middlings .75 and 4.76, 3) corn-soybean meal 1.50 and 9.40, and 4) high wheat middlings 1.50 and 9.40. Cows grazing the high available forage pasture gained 53 Ib more than those grazing the low available forage pasture. The supplement x pasture interaction indicates that level of available forage affects response to the supplemental treatment. When available forage was low, wheat middlings was a less effective source of supplemental protein than soybean meal. When available forage was high, soybean meal and the low wheat middlings supplements resulted in similar cow weight gains. Regardless of forage availability, the high wheat middlings supplement was a less effective source of supplemental energy cornpared to the corn-soybean meal supplement balanced to provide equal protein and energy. The supplement x year interaction resulted from soybean meal being more beneficial than low wheat middlings in year 1 while in year 2, soybean meal and low wheat middlings resulted in similar cow performance
Recommended from our members
Using Interleukin 6 and 8 in Blood and Bronchoalveolar Lavage Fluid to Predict Survival in Hematological Malignancy Patients With Suspected Pulmonary Mold Infection.
Background: Molds and other pathogens induce elevated levels of several cytokines, including interleukin (IL)-6 and IL-8. The objective of this study was to investigate the prognostic value of IL-6 and IL-8 as well as fungal biomarkers in blood and bronchoalveolar lavage fluid (BAL) for overall survival in patients with underlying hematological malignancies and suspected mold infection. Methods: This cohort study included 106 prospectively enrolled adult cases undergoing bronchoscopy. Blood samples were collected within 24 h of BAL sampling and, in a subset of 62 patients, serial blood samples were collected up until 4 days after bronchoscopy. IL-6, IL-8, and other cytokines as well as galactomannan (GM) and β-D-glucan (BDG) were assayed in blood and BAL fluid and associations with overall mortality were assessed at the end of the study using receiver operating characteristic (ROC) curve analysis. Results: Both blood IL-8 (AUC 0.731) and blood IL-6 (AUC 0.699) as well as BAL IL-6 (AUC 0.763) and BAL IL-8 (AUC 0.700) levels at the time of bronchoscopy were predictors of 30-day all-cause mortality. Increasing blood IL-6 levels between bronchoscopy and day four after bronchoscopy were significantly associated with higher 90-day mortality, with similar findings for increasing IL-8 levels. In ROC analysis the difference of blood IL-8 levels between 4 days after bronchoscopy and the day of bronchoscopy had an AUC of 0.829 (95%CI 0.71-0.95; p < 0.001) for predicting 90-day mortality. Conclusions: Elevated levels of IL-6 and IL-8 in blood or BAL fluid at the time of bronchoscopy, and rising levels in blood 4 days following bronchoscopy were predictive of mortality in these patients with underlying hematological malignancy who underwent bronchoscopy for suspected mold infection
On edge intersection graphs of paths with 2 bends
An EPG-representation of a graph G is a collection of paths in a grid, each corresponding to a single vertex of G, so that two vertices are adjacent if and only if their corresponding paths share infinitely many points. In this paper we focus on graphs admitting EPG-representations by paths with at most 2 bends. We show hardness of the recognition problem for this class of graphs, along with some subclasses. We also initiate the study of graphs representable by unaligned polylines, and by polylines, whose every segment is parallel to one of prescribed slopes. We show hardness of recognition and explore the trade-off between the number of bends and the number of slopes. © Springer-Verlag GmbH Germany 2016
Influence of Prototropic Reactions on the Absorption and Fluorescence Spectra of Methyl p-dimethylaminobenzoate and Its Two Ortho Derivatives
The influence of prototropic reactions on the spectral characteristics of methyl p-dimethylaminobenzoate (I) and its o-methoxy (II) and o-hydroxy (III) derivatives has been studied using steady-state spectroscopic technique and quantum-chemical calculations. This study concerns the solvent-induced shift of the absorption, locally excited (LE) and intramolecular charge transfer (ICT) fluorescence bands in the neat tetrahydrofuran (THF) and its hydrochloric acid solutions at different HCl concentrations. On the basis of the experimental results and quantum-chemical calculations, it was shown that in a hydrochloric acid solution the studied molecules exist as a mixture of neutral, mono-, and dicationic forms. Additionally, the results of spectroscopic measurements were used to calculate, according to the Benesi-Hildebrand method, the equilibrium constants of protopropic reactions in the ground, S0, and excited, S1, states. Our findings predestine molecules I and II to be used as acid fluorescence probes in a region of 0–2.5 M of [H+] concentrations
Total Synthesis, Structure, and Biological Activity of Adenosylrhodibalamin, the Non-Natural Rhodium Homologue of Coenzyme B12.
B12 is unique among the vitamins as it is biosynthesized only by certain prokaryotes. The complexity of its synthesis relates to its distinctive cobalt corrin structure, which is essential for B12 biochemistry and renders coenzyme B12 (AdoCbl) so intriguingly suitable for enzymatic radical reactions. However, why is cobalt so fit for its role in B12‐dependent enzymes? To address this question, we considered the substitution of cobalt in AdoCbl with rhodium to generate the rhodium analogue 5′‐deoxy‐5′‐adenosylrhodibalamin (AdoRbl). AdoRbl was prepared by de novo total synthesis involving both biological and chemical steps. AdoRbl was found to be inactive in vivo in microbial bioassays for methionine synthase and acted as an in vitro inhibitor of an AdoCbl‐dependent diol dehydratase. Solution NMR studies of AdoRbl revealed a structure similar to that of AdoCbl. However, the crystal structure of AdoRbl revealed a conspicuously better fit of the corrin ligand for RhIII than for CoIII, challenging the current views concerning the evolution of corrins
Evaluation of Wheat Middlings as a Supplement for Beef Cows Grazing Native Winter Range
A winter grazing trial was conducted at the SDSU Cottonwood Research Station near Cottonwood, SD, to compare wheat middlings to soybean meal and corn-soybean meal supplements. During December and January 122 pregnant Simmental-Angus crossbred cows grazing two pastures with differing amounts of available forage were fed four supplemental treatments that provided the following amounts of crude protein (Ib) and metabolizable energy (Mcal) per cow daily: I) soybean meal .75 and 2.40, 2) corn-soybean meal 1.50 and 9.40, 3) low wheat middlings .75 and 4.76, and 4) high wheat middlings 1.50 and 9.40. Cows grazing the high available forage pasture gained 56 Ib more than those grazing the low available forage pasture. Cows grazing the high available forage pasture were able to select a diet higher in crude protein and lower in acid = detergent fiber. The supplement x pasture interaction indicates that level of forage availability is a factor in determining a cow\u27s response to the supplemental treatment. When forage availability was low, wheat middlings was a less effective source of supplemental protein than soybean meal and a less effective source of supplemental energy compared to a corn-soybean meal supplement balanced to provide equal protein and energy. For cows grazing the high available forage pasture, soybean meal and the low wheat middlings supplements produced similar cow weight gains and the high wheat middlings supplement was a less effective source of supplemental energy than the corn-soybean meal supplement. Cows grazing the high forage pasture receiving 1.89 Ib soybean meal had similar weight gains and lower supplement cost than cows grazing the low forage pasture receiving 6.59Ib of the corn-soybean meal supplement
Cliophysics: Socio-political Reliability Theory, Polity Duration and African Political (In)stabilities
Quantification of historical sociological processes have recently gained
attention among theoreticians in the effort of providing a solid theoretical
understanding of the behaviors and regularities present in sociopolitical
dynamics. Here we present a reliability theory of polity processes with
emphases on individual political dynamics of African countries. We found that
the structural properties of polity failure rates successfully capture the risk
of political vulnerability and instabilities in which 87.50%, 75%, 71.43%, and
0% of the countries with monotonically increasing, unimodal, U-shaped and
monotonically decreasing polity failure rates, respectively, have high level of
state fragility indices. The quasi-U-shape relationship between average polity
duration and regime types corroborates historical precedents and explains the
stability of the autocracies and democracies.Comment: 4 pages, 3 figures, 1 tabl
- …