Pure O-sequences and matroid h-vectors

We study Stanley's long-standing conjecture that the h-vectors of matroid simplicial complexes are pure O-sequences. Our method consists of a new and more abstract approach, which shifts the focus from working on constructing suitable artinian level monomial ideals, as often done in the past, to the study of properties of pure O-sequences. We propose a conjecture on pure O-sequences and settle it in small socle degrees. This allows us to prove Stanley's conjecture for all matroids of rank 3. At the end of the paper, using our method, we discuss a first possible approach to Stanley's conjecture in full generality. Our technical work on pure O-sequences also uses very recent results of the third author and collaborators.Comment: Contains several changes/updates with respect to the previous version. In particular, a discussion of a possible approach to the general case is included at the end. 13 pages. To appear in the Annals of Combinatoric

Infrared Gas Phase Intensity Measurements, Polar Tensors, And Effective Charges Of Vinylidene Fluoride And Its Deuterated Modifications

All gas phase fundamental vibrational intensities for vinylidene fluoride and its deuterated modifications have been measured. Isotopic invariance, G sum rule, and quantum chemical information have been used in selecting preferred experimental values for the dipole moment derivatives and polar tensor elements of these molecules. The values of these intensity parameters are compared with those found for other molecules. The experimental values are interpreted in terms of electronic charge distortions occurring in these molecules for the various vibrations. © 1982 American Institute of Physics.7731099110

Rivaroxaban with or without Aspirin in Stable Cardiovascular Disease

BACKGROUND We evaluated whether rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary cardiovascular prevention. METHODS In this double-blind trial, we randomly assigned 27,395 participants with stable atherosclerotic vascular disease to receive rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg once daily), rivaroxaban (5 mg twice daily), or aspirin (100 mg once daily). The primary outcome was a composite of cardiovascular death, stroke, or myocardial infarction. The study was stopped for superiority of the rivaroxaban-plus-aspirin group after a mean follow-up of 23 months. RESULTS The primary outcome occurred in fewer patients in the rivaroxaban-plus-aspirin group than in the aspirin-alone group (379 patients [4.1%] vs. 496 patients [5.4%]; hazard ratio, 0.76; 95% confidence interval [CI], 0.66 to 0.86; P<0.001; z=−4.126), but major bleeding events occurred in more patients in the rivaroxaban-plus-aspirin group (288 patients [3.1%] vs. 170 patients [1.9%]; hazard ratio, 1.70; 95% CI, 1.40 to 2.05; P<0.001). There was no significant difference in intracranial or fatal bleeding between these two groups. There were 313 deaths (3.4%) in the rivaroxaban-plus-aspirin group as compared with 378 (4.1%) in the aspirin-alone group (hazard ratio, 0.82; 95% CI, 0.71 to 0.96; P=0.01; threshold P value for significance, 0.0025). The primary outcome did not occur in significantly fewer patients in the rivaroxaban-alone group than in the aspirin-alone group, but major bleeding events occurred in more patients in the rivaroxaban-alone group. CONCLUSIONS Among patients with stable atherosclerotic vascular disease, those assigned to rivaroxaban (2.5 mg twice daily) plus aspirin had better cardiovascular outcomes and more major bleeding events than those assigned to aspirin alone. Rivaroxaban (5 mg twice daily) alone did not result in better cardiovascular outcomes than aspirin alone and resulted in more major bleeding events. (Funded by Bayer; COMPASS ClinicalTrials.gov number, NCT01776424.

Infrared Gas-phase Intensity Measurements, Polar Tensors, And Effective Charges Of Trans-difluoro- And Trans-dichloroethylene

All gas-phase fundamental vibrational intensities of trans-C2H2F2, -C2D2F2, -C2HDF2, -C2H2Cl2 and -C2D2Cl2 have been measured. Isotopic invariance, G sum rule, and quantum chemical information have been used as criteria in selecting preferred experimental values for the dipole-moment derivatives and polar-tensor elements of the Bu (infrared-active) symmetry species of these molecules. The polar tensors of cis-C2H2F2 and -C2H2Cl2 are shown to provide accurate estimates of the vibrational intensities of all the above-mentioned trans-difluoro- and trans-dichloroethylenes, respectively. These polar tensors are also used to calculate the directions of the in-plane dipole-moment derivatives of these molecules. © 1984 American Chemical Society.88352152