Contraction blockers for graphs with forbidden induced paths.

We consider the following problem: can a certain graph parameter of some given graph be reduced by at least d for some integer d via at most k edge contractions for some given integer k? We examine three graph parameters: the chromatic number, clique number and independence number. For each of these graph parameters we show that, when d is part of the input, this problem is polynomial-time solvable on P4-free graphs and NP-complete as well as W[1]-hard, with parameter d, for split graphs. As split graphs form a subclass of P5-free graphs, both results together give a complete complexity classification for Pℓ-free graphs. The W[1]-hardness result implies that it is unlikely that the problem is fixed-parameter tractable for split graphs with parameter d. But we do show, on the positive side, that the problem is polynomial-time solvable, for each parameter, on split graphs if d is fixed, i.e., not part of the input. We also initiate a study into other subclasses of perfect graphs, namely cobipartite graphs and interval graphs

The Land Scouts: Guide Book

The Land Scouts promote modern land stewardship and are open to all. The Guide Book gives an overview of the scouts as well as information on getting started earning badges and hosting a troop.https://digitalcommons.snc.edu/faculty_staff_works/1004/thumbnail.jp

Clinical study comparing ketorolac tromethamine with diclofenac sodium for the treatment of ocular surface inflammations

Thirty patients with various ocular surface inflammations were enrolled in a double-masked study comparing ketorolac tromethamine 0.5% (Acular) and diclofenac sodium 0.1% (Voltaren Ophthalmic). At the initial visit, baseline measurements of various inflammatory signs were taken. The patients were instructed to use Acular in one eye and Voltaren Ophthalmic in the other eye four times a day for a period of seven days. After this seven day treatment period, the patients completed a questionnaire and were evaluated for signs of inflammation. At this time, the drops were reversed for each eye. Once again the patients were instructed to use the drops four times daily for seven days. After this second week of treatment the patients were reevaluated for signs and symptoms of inflammation. Quantification of signs and symptoms occurred at the one week and two week evaluations. After two weeks the Acular-treated eyes showed significant decreases in conjunctival injection (p = 0.0192), tear debris (p = 0.0052), papillae (p = 0.0092), and follicles (p = 0.0046) compared to baseline. The Voltaren Ophthalmic-treated eyes showed significant decreases in chemosis (p = 0,0113), conjunctival injection (p = 0.0268), tear debris (p = 0.0373), papillae (p = 0.0068), and follicles (p = 0.0039). Subjectively patients found more overall satisfaction with Voltaren Ophthalmic than with Acular (p = 0.0010). Results of this study show that both Acular and Voltaren Ophthalmic are effective in reducing the signs of ocular surface inflammations

An improved model for the Earth's gravity field

An improved model for the Earth's gravity field, TEG-1, was determined using data sets from fourteen satellites, spanning the inclination ranges from 15 to 115 deg, and global surface gravity anomaly data. The satellite measurements include laser ranging data, Doppler range-rate data, and satellite-to-ocean radar altimeter data measurements, which include the direct height measurement and the differenced measurements at ground track crossings (crossover measurements). Also determined was another gravity field model, TEG-1S, which included all the data sets in TEG-1 with the exception of direct altimeter data. The effort has included an intense scrutiny of the gravity field solution methodology. The estimated parameters included geopotential coefficients complete to degree and order 50 with selected higher order coefficients, ocean and solid Earth tide parameters, Doppler tracking station coordinates and the quasi-stationary sea surface topography. Extensive error analysis and calibration of the formal covariance matrix indicate that the gravity field model is a significant improvement over previous models and can be used for general applications in geodesy

The THO complex as a key mRNP biogenesis factor in development and cell differentiation

The THO complex is a key component in the co-transcriptional formation of messenger ribonucleoparticles that are competent to be exported from the nucleus, yet its precise function is unknown. A recent study in BMC Biology on the role of the THOC5 subunit in cell physiology and mouse development provides new clues to the role of the THO complex in cell differentiation

The Pulsed Neutron Beam EDM Experiment

We report on the Beam EDM experiment, which aims to employ a pulsed cold neutron beam to search for an electric dipole moment instead of the established use of storable ultracold neutrons. We present a brief overview of the basic measurement concept and the current status of our proof-of-principle Ramsey apparatus