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The susceptibility of highly purified human CD34+ cells to monocytotropic (Ba-L) and lymphotropic (A018-post) strains of human immunodeficiency virus-1 (HIV-1) was examined. Liquid cultures initiated with fresh immunomagnetically purified CD34+ cells using the K6.1 CD34 monoclonal antibody (MoAb) (K6.1/CD34+) were positive for HIV expression 2 weeks after exposure to HIV-1 Ba-L. These cells were initially greater than 90% CD34+ and had undetectable monocyte contamination by flow-cytometric staining and side-scatter analyses, respectively, and undetectable T-cell contamination by CD3 polymerase chain reaction (PCR) analysis. However, secondary CD34+ liquid cultures reselected from the primary liquid cultures 24 hours after HIV exposure by panning with the ICH3 CD34 MoAb (ICH3/CD34+) and maintained for an additional 14 days were negative for HIV expression. The ICH3-unbound cells were positive for both spliced and unspliced HIV RNA when exposed to HIV-1 Ba-L, and were DNA PCR positive when exposed to either monocytotropic or lymphotropic HIV-1. To further test that CD34+ cells were not infectible by HIV-1, we exposed K6.1/CD34+ cells continuously to HIV-1 in a culture system capable of maintaining and expanding primitive CD34+ cells. HIV-exposed K6.1/CD34+ cells proliferated and expanded as efficiently as uninfected cultures. However, when reselected magnetically using the K6.1 CD34 MoAb after expansion for 7 days, bound K6.1/CD34+ cells were again negative for HIV-1 expression, whereas unbound cells were positive for HIV-1 expression. These findings suggest that a sequential CD34+ cell-selection process, in which the two selections are separated by a brief culture period, can yield a population of CD34+ cells that are not infected with HIV-1. This process may be useful in the design of stem or progenitor cell- based transplantation therapies for HIV infection.

performance and behavior at work. Effective physician leadership is instrumental to improved patient satisfaction, reduced length of stay, and better integration of clinical care across service lines. To be effective, physician leaders must master multiple clinical and leadership competencies, including interpersonal skills. When leaders learn to use interpersonal skills, they are able to apply them in a wide variety of specific activities, including leading teams, coaching, and managing conflict. This preconference program is offered in partnership with the American Association for Physician Leadership. This session applies to all physician leaders and practice settings looking to increase their effectiveness as a team leader. Primary leadership competencies addressed in this program include interpersonal skills, communication skills, and the ability to convey a clear, compelling vision.

Thomas Reid (1710–1796) was a philosopher who founded the Scottish school of 'common sense'. Much of Reid's work is a critique of his contemporary, David Hume (1711–1776), whose empiricism he rejects. In this work, written after Reid's appointment to a professorship at the university of Glasgow, and published in 1785, he turns his attention to ideas about perception, memory, conception, abstraction, judgement, reasoning and taste. He examines the work of his predecessors and contemporaries, arguing that 'when we find philosophers maintaining that there is no heat in the fire, nor colour in the rainbow … we may be apt to think the whole to be only a dream of fanciful men, who have entangled themselves in cobwebs spun out of their own brain'. Written by one of the Scottish Enlightenment's most important thinkers, this work brings to life the intellectual debates of the time.

The Scottish philosopher Thomas Reid (1710–1796) first published Essays on Active Powers of Man in 1788 while he was Professor of Philosophy at King's College, Aberdeen. The work contains a set of essays on active power, the will, principles of action, the liberty of moral agents, and morals. Reid was a key figure in the Scottish Enlightenment and one of the founders of the 'common sense' school of philosophy. In Active Powers Reid gives his fullest exploration of sensus communis as the basis of all philosophical inquiry. He uses common sense realism to argue for the existence of a stable external world, the existence of other minds, and to offer a powerful challenge to versions of the Theory of Ideas advocated by Hume (1711–1776) and Locke (1632–1704). This is a key work of the Scottish Enlightenment that made important contributions to fundamental debates about the basis of philosophical inquiry.

A truly unsteady approach for the numerical simulation of in-flight electro-thermal antiicing or de-icing using a Conjugate Heat Transfer (CHT) technique is presented. This numerical approach has been implemented in FENSAP-ICE to compute the complex heat transfer phenomena occurring during in-flight de-icing with multiple heating elements. At each time step, the energy fluxes through the aircraft solid skin, the melting ice layer, the liquid water film and the external fluid are computed. The ice shape is then modified by taking into account the mass balance of ice accreting due to the impact of supercooled droplets and water runback, and the melting of the ice layer due to heating. The results of the verification of the phase-change conduction code are presented, followed by a study of inter-cycle de-icing on a wing using CHT, showing inter-cycle ice growth.

The main objective of a code verification process is to assess using known solutions if the algorithm implemented in the code is adequately representing the conceptual model. Verification of Codes requires either exact or highly accurate results that can be obtained using a reference code. This paper presents a new method of code comparison. The reference code is first verified via comparison with exact solutions using the Method of Manufactured Solutions (MMS). Another convergence study is then performed with the reference code, without the MMS source terms, to provide a reference solution. Finally, the same test is run using the code to be verified. The convergence properties of the benchmarked code can then be assessed, and results of both codes can be compared by taking into account all numerical uncertainties.