Sorting by Transpositions is an NP-hard problem for which several polynomial-time approximation algorithms have been developed. Hartman and Shamir (2006) developed a 1.5-approximation [Formula: see text] algorithm, whose running time was improved to O(nlogn) by Feng and Zhu (2007) with a data structure they defined, the permutation tree. Elias and Hartman (2006) developed a 1.375-approximation ...

A Steiner quadruple system (X, B) is said to be (1, 2)-resolvable if its blocks can be partitioned into r parts such that each point of X occurs in exactly two blocks in each part. The necessary condition for the existence of (1, 2)-resolvable Steiner quadruple systems RSQS(1, 2, v)s is v ≡ 2 or 10 (mod 12). Hartman and Phelps in [A. Hartman, K.T. Phelps, Steiner quadruple systems, in: J.H. Din...

1 Mones JM, Saldana MJ, Oldham SA. Diagnosis of Pnewnocysti.s carinii pneumonia. Roentgenographic-pathologic correlates based on fiberoptic bronchoscopy specimens for patients with the acquired immunodeficiency syndrome. Chest 1986; 89:522-26 2 Hartman B, Koss M, Hui A, Baumann W, Athos L, Boylen T Pneumocystis carinii pneumonia in the acquired immunodeficiency syndrome (AIDS). Diagnosis with b...

Thoracophelia (Annelida, Opheliidae) are burrowing deposit feeders generally found in the mid- to upper intertidal areas of sandy beaches. Thoracophelia mucronata (Treadwell, 1914) is found along the west coast of North America, including at Dillon Beach, CA. Two additional species, Thoracophelia dillonensis (Hartman, 1938) and T. williamsi (Hartman, 1938) were also described from this beach. T...

s and proceedings from the American Council of Academic Plastic Surgeons Winter Retreat that was held on February 6–7, 2016, in Chicago, Ill. Presented at the American Council of Academic Plastic Surgeons Winter Retreat, February 6 and 7, 2016, Chicago, Ill. 2016 ACAPS Winter Retreat Meeting AbstrActs

this paper gives a short survey of some of the known results generalizing the theorem, credited to i. schur, that if the central factor group is finite then the derived subgroup is also finite.