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This report covers the teaching of African languages in American universities and by the United States Government since September, 1961. It is based on 100 percent response to a questionnaire circulated in the spring of 1966. Data are for languages actually taken for credit, not for those that were offered but did not materialize, or that were taken on an informal basis.
The principal facts about university programs are summarized in the accompanying graph. The number of student-semester-hours is shown as a solid line, the number of schools as a broken line, and the number of different languages as a dotted line.
The most obvious trend is, of course, rapid growth. The number of schools that teach African languages and the number of languages taught have more than doubled in five years, and the number of student-semester-hours has increased nearly sevenfold. Another major trend is toward maturity. The ratio of languages to schools has remained nearly constant at about 1.4, while the number of student-semester-hours per language has risen from 57 in 1961 to 172 in 1965. The increase in number of schools and number of languages seems to be leveling off, but the number of student-semester-hours is rising at an increasing rate.
This study examines the similarity properties of hypersonic turbulent boundary layers using direct numerical simulations within a two-species mixture, composed of molecular and atomic oxygen. A dissociation–recombination mechanism is considered, at varying reaction rates. The results show that while the hydrodynamic field remains largely unaffected by changes in reaction rates, temperature profiles are slightly altered, with faster reactions leading to lower temperature peaks. The chemical mechanisms significantly influence the wall heat flux, with frozen chemistry overestimating the flux. The reference simulations are compared with companion calculations, where chemical reactions are activated downstream within the fully turbulent region. These calculations represent set-ups in which the computational domain effectively starts with an inflow in a fully turbulent state, where hydrodynamic and thermal quantities are accurately described at the boundary and the chemical inflow profile is derived from a frozen-chemistry assumption. In this set-up, chemical source terms rapidly relax towards the baseline downstream of the chemistry activation location. This behaviour is due to an approximate global self-similarity shown by the chemical species transport in the fully turbulent region. Unlike laminar boundary layers where streamwise fluxes are relevant, source terms are balanced only by wall-normal transport in the turbulent region. A chemical relaxation length scale is introduced to collapse the results of all mechanisms.
The Erdős-Sós Conjecture states that every graph with average degree exceeding $k-1$ contains every tree with $k$ edges as a subgraph. We prove that there are $\delta \gt 0$ and $k_0\in \mathbb N$ such that the conjecture holds for every tree $T$ with $k \ge k_0$ edges and every graph $G$ with $|V(G)| \le (1+\delta )|V(T)|$.
The reactivity of transverse waves in detonations of methane, oxygen and nitrogen are experimentally assessed using MHz rate schlieren and chemiluminescence imaging. In these highly unstable mixtures, the mode of wave propagation is more complex than what is described by the cellular instability model that is conventionally used for weakly unstable mixtures. Behind the low-speed leading shock in unstable waves, the processed gas remains essentially unreacted until transverse waves reach this region. In highly unstable waves, the transverse waves have a range of reactivity, that is rates of reaction in the flow immediately behind the wave. In this study, we present examples of transverse waves for near-limit detonations and analyse four cases in detail. In some cases, these waves appear to be essentially non-reactive or cause very slow reaction. In other cases, the transverse waves can be highly reactive. In the most extreme example, the transverse wave is propagating at the Chapman–Jouguet speed with a small reaction zone, i.e. a transverse detonation. A reactive oblique shock model is used to approximate the triple-point configuration of this case as a double-Mach reflection, which shows good agreement with the images. The reaction evolution along path lines is analysed using detailed reaction mechanisms and considerations about flow-field unsteadiness. Length scales of the energy release and expansion processes within the reaction zone region are used to explain the observed modes of wave propagation and interaction.
Strengthening the research workforce is essential for meeting the evolving needs and challenges in the health and biomedical fields. To do so effectively, it requires an understanding of how the experiences of a researcher shift over time and how one’s research career evolves, particularly as supports are put in place to foster research. This narrative review provides a summary of published individual-level assessment measures and survey tools from 2000–2024. All measures were abstracted, classified, and coded during analyses to describe the areas of focus, and they were organized into one of six research categories. The review identified a range of measures and methods across all categories. However, the measures were often narrow, focused on outputs, and not ideal for assessing the full range of experiences a researcher may have throughout their career. The most common metrics were related to research productivity and bibliometric measures. Our review of survey tools revealed a gap in comprehensive approaches available to assess an individual’s research experience, efforts, supports, and impact. As efforts expand to evaluate and study the research workforce, tools that focus on a broad range of individual-level measures, tied to specific underlying constructs and drawn from the literature, may prove useful.
This conference was held at the University of Illinois, Champaign-Urbana, December 8 to 10, 1966, under the cochairmanship of Professor Frank Willett (Northwestern University) and Dr. Brian M. Fagan (University of Illinois). Thirteen persons in some way associated with Iron Age archaeology were official participants, and there were six observers who also contributed to the discussions. The names of these participants are listed at the end of this article. Their primary concern was with the archaeology of Africa since the origins of food production, with special reference to the Iron Age.
As a guideline the participants were given brief reports on four recent conferences which had touched on the problems of African Iron Age archaeology. Terminology and research needs, primarily for the Stone Age, were topics at the Wenner Gren Symposium on the African Quaternary held at Burg Wartenstein, Austria, in July, 1965. The results of this symposium were reviewed at the meeting of West African archaeologists in Sierra Leone during June, 1966. This meeting also expressed concern at the shortage of manpower and resources in West African archaeology, especially in the French-speaking territories, and training facilities and other terminological problems were also discussed. The difficulties of communication and training, especially in related disciplines, were discussed by a group attending an ARC meeting on the African Arts in March, 1966.
There is an increasing need of the government to know more about Africa. Trying to look ahead, many of us can see, for example, continued instability on the continent, with weak, fragile states grappling with the problems of achieving national cohesion. As we confront the problems arising from this instability, the gaps in our knowledge and understanding are vast and our need to know will probably continue to be much greater than our capacity to find the answers.
The African Studies Association's forthcoming bookThe African World: A Survey of Social Research has symbolic as well as substantive value for FAR insofar as it demonstrates how a group with widely diversified disciplines, interests, and missions can devise effective channels of communication to share a clearer understanding of each participant's special problems and objectives. The ASA asked the specialists in each of the 18 disciplines represented in this book to discuss, in relatively simple language and for the benefit of those in other disciplines, the problems they study in Africa, their methods, successes, and major failures.
We address the Reynolds number dependence of the turbulent skin-friction drag reduction induced by streamwise-travelling waves of spanwise wall oscillations. The study relies on direct numerical simulations of drag-reduced flows in a plane open channel at friction Reynolds numbers in the range $1000 \leqslant Re_\tau \leqslant 6000$, which is the widest range considered so far in simulations with spanwise forcing. Our results corroborate the validity of the predictive model proposed by Gatti & Quadrio (J. Fluid Mech. vol. 802, 2016, pp. 553–558): regardless of the control parameters, the drag reduction decreases monotonically with $Re$ at a rate that depends on the drag reduction itself and on the skin-friction of the uncontrolled flow. We do not find evidence in support of the results of Marusic et al. (Nat. Commun. vol. 12, no. 1, 2021, pp. 5805), which instead report by experiments an increase of the drag reduction with $Re$ in turbulent boundary layers, for control parameters that target low-frequency, outer-scaled motions. Possible explanations for this discrepancy are provided, including obvious differences between open channel flows and boundary layers, and possible limitations of laboratory experiments.
The American University offers courses in the study of Africa among different disciplines and also Africa area studies on an interdisciplinary basis.
It is recognized that there is a need for people who have a specialized discipline in one aspect of Africa, such as anthropology, linguistics, history, economics, or political science. There is also a need for a “general practitioner” (interdisciplinary or multidisciplinary) approach. Students are given the opportunity to pursue either procedure, or a combination of these procedures.
A student may study for an M.A. in African area studies, or for an M.A. or Ph.D. in international relations, government and public administration, business administration, or in one of the other disciplines in The American University, with an emphasis on Africa. A student may also study for an M.I.S. (Master of International Service), with an emphasis on Africa.
The larger proportion of the graduate students in African studies have already had some professional experience in Africa and come here for either strengthening special needs or for more general breadth for their future work related to Africa. The American University provides an opportunity for a flexible program to meet particular needs as well as general interests of students.
The African Studies Program at The American University in Washington, D.C. has the special advantages of close association with African embassies, U.S. government departments, and the United Nations, in addition to research facilities of the Library of Congress. Students here also have the opportunity for contact with scholars who are specializing in other ares of the world which are having increasing relationships with Africa - - including Europe, Asia, the Middle East, and Latin America.
The Africa collections at Stanford University are housed largely in the University Library, the library of the Food Research Institute, and the Hoover Institution on War, Revolution, and Peace. Although the major portion of the material is found in the Hoover Institution, the other two libraries constitute important resources. Special collections are located in the Branner Library (Geology), the Cubberley Library (Education), the Lane Medical Library, and the Law Library. The curator of the Hoover Africa Collection assists all university libraries by recommending titles of old and new items so that the various collections develop in all fields.
The University Library buys widely in the African field but accepts primary responsibility for all African material before 18 70 and in the areas of art, ethnography, geography, linguistics, literature, religion, sociology, statistics, and technical documents. The Government Documents Division receives general statistical annuals and bulletins from all African countries and statistical reports of foreign trade from most countries. An effort is made to acquire all census and development-planning material. Most departmental reports are also received. The Documents Division was long an official depository for British government documents and thus contains an outstanding collection of parliamentary debates, blue books, command papers, Foreign Office papers, and annual reports of the Colonial Office from the early nineteenth century. For France the debates of the Assemblée Nationale are held from 18 71 and the Journal Officiel from 1914; for Germany the Reichstag debates are complete from 1867. These together with the depository publications of the United Nations make a substantial collection of material relevant to Africa.
In September and October of 1964, I visited the various centers once forming links in the archival system of French West Africa. Contrary to what occurred in Equatorial Africa, the French left these archival holdings in place, except for current material which was shipped to the rue Oudinot (Ministry of Colonies) in Paris. The center of the West African system was the Archives of the Government-General in Dakar (later the High Commission). Based originally on the Senegalese holdings, this archive became an independent agency of the federal government and was the parent organization of subsidiary archives for Senegal, Mauritania, Soudan, Upper Volta, Niger, Dahomey, Ivory Coast, and Guinea. It was parallel in structure to the Institut Français d'Afrique Noire (IFAN), which also had its headquarters in Dakar and maintained subsidiary centers for each territory. In some cases, the archives and IFAN centers were amalgamated (during World War II) and the history of the two organizations is often inseparable. This survey is an attempt to describe the establishment and development of these archival centers, how their material was organized and can be used for research, and their current status in the independent countries.