Top Trading Cycles, Consistency, and Acyclic Priorities for House Allocation with Existing Tenants

We study the house allocation with existing tenants model (Abdulkadiroğlu and Sönmez, 1999) and consider rules that allocate houses based on priorities. We introduce a new acyclicity requirement and show that for house allocation with existing tenants a top trading cycles (TTC) rule is consistent if and only if its underlying priority structure satisfies our acyclicity condition. Next we give an alternative description of TTC rules based on ownership-adapted acyclic priorities in terms of two specific rules, YRMH-IGYT (you request my house - I get your turn) and efficient priority rules, that are applied in two steps. Moreover, even if no priority structure is a priori given, we show that a rule is a top trading cycles rule based on ownership-adapted acyclic priorities if and only if it satisfies Pareto-optimality, individual-rationality, strategy-proofness, consistency, and either reallocation-proofness or non-bossiness

Occupancy Classification of Position Weight Matrix-Inferred Transcription Factor Binding Sites

BACKGROUND: Computational prediction of Transcription Factor Binding Sites (TFBS) from sequence data alone is difficult and error-prone. Machine learning techniques utilizing additional environmental information about a predicted binding site (such as distances from the site to particular chromatin features) to determine its occupancy/functionality class show promise as methods to achieve more accurate prediction of true TFBS in silico. We evaluate the Bayesian Network (BN) and Support Vector Machine (SVM) machine learning techniques on four distinct TFBS data sets and analyze their performance. We describe the features that are most useful for classification and contrast and compare these feature sets between the factors. RESULTS: Our results demonstrate good performance of classifiers both on TFBS for transcription factors used for initial training and for TFBS for other factors in cross-classification experiments. We find that distances to chromatin modifications (specifically, histone modification islands) as well as distances between such modifications to be effective predictors of TFBS occupancy, though the impact of individual predictors is largely TF specific. In our experiments, Bayesian network classifiers outperform SVM classifiers. CONCLUSIONS: Our results demonstrate good performance of machine learning techniques on the problem of occupancy classification, and demonstrate that effective classification can be achieved using distances to chromatin features. We additionally demonstrate that cross-classification of TFBS is possible, suggesting the possibility of constructing a generalizable occupancy classifier capable of handling TFBS for many different transcription factors

Evaluation of therapeutic potential of intraperitoneal ozone gas in combination with insulin above cranial and spinal neuropathy in rats with diabetes mellitus

OBJECTIVE: This study aimed to investigate the therapeutic effect of ozone in combination with insulin on cranial and spinal neuropathy in rats with diabetes mellitus (DM)

Effects of intestinal ischemia-reperfusion on major conduit arteries

Intestinal ischemia-reperfusion (I-R) is a common and serious clinical condition associated with simultaneous remote organ dysfunction. The purpose of this study was to investigate the effects of intestinal I-R on the vasomotor functions of major conduit arteries. Anesthetized rabbits were randomly assigned to one of three groups: sham-operated controls (Group I), and one-hour intestinal ischemia with two-hour reperfusion (Group II) or four-hour reperfusion (Group III). The following mechanisms of vasomotor functions were studied in abdominal aorta, superior mesenteric, renal, pulmonary, and carotid arterial rings: (1) endothelial-dependent vasodilation response to acetylcholine, (2) endothelial-independent vasodilation response to nitroprusside, (3) beta-adrenergic vasodilation response to isoproterenol, and (4) phenylephrine-induced vasoconstriction. Intestinal injury was quantified using malondialdehyde (MDA) concentration and wet-to-dry intestine weight ratio. Intestinal I-R did not affect the maximal responsiveness or the sensitivity to acetylcholine, nitroprusside, and isoproterenol in all the vessels studied. The maximal contractile response to phenylephrine increased significantly in mesenteric artery in Group II, (227.1 +/- 15.1% vs 152.8 +/- 11.7% in controls) (p < 0.05). Intestinal MDA concentration, a marker of oxidant injury, increased from 39.87 +/- 9.41 nmol/g to 67.8 +/- 8.8 nmol/g in group II (p < 0.01), and to 94.8 +/- 7.56 nmol/g in Group III (p < 0.001). Wet-to-dry intestine weight ratio increased from 3.62 +/- 0.12 to 4.28 +/- 0.17 in Group II (p < 0.01), to 4.62 +/- 0.14 in Group III (p < 0.001). These data indicate that although the intestines of the animals subjected to intestinal I-R are seriously injured, the smooth muscle relaxation of major conduit arteries was not affected