11,334 research outputs found
The Prevention of the Ice Hazard on Airplanes
A review of various methods to prevent ice formation and adhesion to aircraft surfaces is given. It was concluded that the adhesion of ice to a surface may be reduced somewhat by the application of certain waxes and varnishes. In the experiments described, the varnishes containing calcium stearate and calcium oleate gave the best results. In wind tunnel tests, the adhesion was further reduced by the application of these waxes and varnishes to a thin, heat insulating layer of rubber. The adhesion of ice is greatly reduced when the surface consists of a vehicle which carries an oil in sufficient quantity so that the surface of the vehicle is self lubricating. Ice may be removed from wings, struts, wires and other parts of an airplane during flight by the inflation of properly constructed pneumatic rubber members, providing that these members have been previously treated with a suitable low adhesion oil
Toward the Integration of Economics and Outdoor Recreation Management
The general theme of this bulletin is that improved management of
public-sector recreational resources is a multidisciplinary task. To this
end, we attempt to integrate elements of outdoor recreation management
theory and economics. The bulletin is written for both resource managers
and researchers. For the former, our intent is to emphasize the importance
of being aware of economic implications-at least conceptually-of
management actions that influence the character and availability of recreational
opportunities. To researchers involved in developing recreation
management theory, we draw attention to the parallel between recreation
management theory and the traditional managerial economic model
of the firm. To economists, particularly those involved in developing
and applying nonmarket valuation techniques, we draw attention to the
types of decisions faced by resource managers.
We argue that the most important resource allocation issues are of
the incremental variety, so nonmarket valuation should also yield incremental
values. These values alone, however, are not sufficient
economic input into rational public choice analysis. The missing link ,
or nexus, between outdoor recreation management theory and economic
analysis is the integration of supply and demand, as called for by traditional
managerial economics. Collaborative research to develop recreation
supply response functions akin to agricultural production functions
is an essential step that is missing from both literatures. Theoretical and
applied work assume greater practical importance if they feed information
into this broadened framework. It is our hope that this bulletin will
bring the disciplines closer to that realization
Oral Verse-Making in Homer's Odyssey
William C. Scott (Humanities Research Professor of Classics at Dartmouth College) has a special interest in classical Greek poetry, both epic and tragic. He has written widely on classical authors; his major works include The Oral Nature of the Homeric Simile, A Commentary on Prometheus Bound, a translation of Plato's Republic, and Musical Design in Aeschylean Theater, which was awarded the 1986 Goodwin Award of Merit by the American Philological Association
Do Repatriation Taxes Matter? Evidence from the Tax Returns of U.S. Multinationals
An open question in the literature on the taxation of multinational corporations is whether repatriation taxes influence whether the profits of foreign subsidiaries are repatriated or reinvested abroad. Theoretical models suggest that dividend remittances should not be influenced by repatriation taxes. The results of recent empirical work indicate that dividend remittances are sensitive to repatriation taxes. This paper investigates whether the empirical evidence can be reconciled with the theoretical results by recognizing that repatriation taxes on dividends may vary over time and provide firms with an incentive to time repatriations so that they occur in years when repatriation tax rates are relatively low. We use information about cross-country differences in tax rates to separately estimate the influence of permanent tax changes, as would occur due to changes in statutory tax rates, and transitory tax changes on dividend repatriations. Our data contains U.S. tax return information for a large sample of U.S. corporations and their foreign subsidiaries. We find that the permanent tax price effect is significantly different from the transitory price effect and is not significantly different from zero, while the transitory tax price effect is negative and significant. This suggests that repatriation taxes do affect dividend repatriation behavior but only to the extent that they vary over time. Previous empirical work has apparently measured the effect of timing behavior.
Sequential induction of NF-κB/Rel family proteins during B-cell terminal differentiation
The NF-kappa B/Rel family of at least five transcription factor polypeptides is thought to function both as a developmental regulator in B cells and as a rapid response system in all cells. To examine this notion in more detail, we determined the protein contents of both the inducible and constitutive NF-kappa B/Rel activities in a pre-B-cell line, 70Z/3, and a mature B-cell line, WEHI 231. NF-kappa B p50/p65 is the major inducible nuclear complex after lipopolysaccharide or phorbol myristate acetate treatment of 70Z/3 cells. The constitutive and inducible complexes in WEHI 231 cells are mainly composed of p50 and Rel. The constitutive or induced activities are all sensitive to I kappa B-alpha, but this inhibitor is very short-lived in WEHI 231 cells, suggesting that the balance between synthesis and degradation of I kappa B-alpha determines whether a particular cell lineage has constitutive activity. A patterned expression of the NF-kappa B/Rel activator proteins emerges from an analysis of other B-lineage cell lines and splenic B cells: mainly p50 and p65 in pre-B (and non-B) cells, a predominance of Rel and p50 in mature B cells, and expression of p52 and RelB in plasmacytoma lines. This ordered pattern of regulators may reflect the requirement for expression of different genes during terminal B-cell differentiation because different combinations of NF-kappa B/Rel family members preferentially activate distinct kappa B sites in reporter constructs
Reexamining the Racial Record of Abraham Lincoln
Since his death in 1865 Abraham Lincoln has been universally honored in black America. In many black homes and businesses, his photograph often hangs in honor next to the one of Martin Luther King Jr. But a new book by Ebony editor Lerone Bennett Jr. contends that Lincoln was a crude bigot who told demeaning darky jokes, had an unquenchable thirst for minstrel shows, consistently used the word nigger, and supported efforts to ship Negroes back to Africa.
As Jack E. White pointed out in a recent Time magazine article, this book largely has been ignored by the mainstream press. The book was not reviewed in The Washington Post, The New Yorker, The Chicago Tribune, or USA Today.
JBHE [Journal of Blacks in Higher Education] asked a group of leading Lincoln scholars for their opinions of the Bennett book and the controversy surrounding its publication. Here are the replies
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