Changes in swimming technique during time to exhaustion at freely chosen and controlled stroke rates

The aim of this study was to assess technical changes during constrained swimming in time-to-exhaustion tests. Ten swimmers of national standard performed a maximal 400-m front crawl and two sets of exhaustion tests at 95%, 100%, and 110% of mean 400-m speed. In the first set (free), swimmers had to maintain their speeds until exhaustion and mean stroke rate was recorded for each test. In the second set (controlled), the same speed and individual corresponding stroke rate were imposed. The durations of the exhaustion tests, relative durations of the stroke phases, and arm coordination were analysed. For each speed in the "controlled" set, the exhaustion tests were shorter. Moreover, variables were consistent, suggesting a stabilization of stroke technique. Under the free condition, stroke rate increased to compensate for the decrease in stroke length. At the same time, swimmers reduced the relative duration of their non-propulsive phases in favour of the propulsive phases. Thus, swimmers changed their arm coordination, which came close to an opposition mode. These two constraints enable swimmers both to maintain their stroking characteristics and develop compensatory mechanisms to maintain speed. Moreover, stroke rate can be seen as a useful tool for controlling arm technique during paced exercise.     

Archives in the trenches: repatriation of African National Congress liberation archives in diaspora to South Africa

The African National Congress (ANC) liberation archives were created in countries all over the world. These liberation archives form part of the national archival heritage of South Africa as they bridge the gap of undocumented history of people who were previously marginalised by the apartheid government. After the ban on liberation movements was lifted in South Africa, the ANC embarked on the process of identification and repatriation of the records that were fragmented throughout the world. This study investigated the approaches followed by the ANC in identifying and repatriating its liberation archives from the trenches to make them accessible. Qualitative data were collected through interviews with purposively selected employees of the African National Congress, MultiChoice, Africa Media Online and the Nelson Mandela Foundation who were involved in the repatriation of the liberation archives. Interview data were augmented through content analysis of ANC documents such as policies, websites and annual reports, as well as observation of the storage conditions of the liberation archives. The key findings revealed that the ANC established an archives management committee that played an important role in the identification, repatriation and, ultimately, digitisation of liberation archives. The committee utilised former liberation struggle members to identify records in ANC hosts in various countries. It was established that, although the ANC was aware of where its records were abroad, not all its records were repatriated to South Africa after the unbanning of the liberation movements. For example, there were host nations, like Italy, that disputed the return of the ANC liberation archives to South Africa. The liberation archives are in the custody of the Fort Hare University as a chosen official repository for the ANC. It is concluded that the repatriation of the liberation archives is an ongoing process, as not all records have been repatriated to South Africa. As the ANC is in power at the time of writing, this is the opportunity for the organisation to negotiate with countries that still have custody of its liberation archives, such as Italy, to repatriate such records to South Africa. A further study on legal ownership and copyright, digitisation and ensuring the authenticity of the ANC liberation archives is recommended. This study can be extended to other liberation movements in southern Africa.     

In search of useful theory of innovation

This essay presents an overview of the prevailing theoretical literature on innovation, probes the adequacy of existing theory to guide policy regarding innovation, and sketches some directions for more fruitful theorizing. The focus is on the vast interindustry differences in rates of productivity growth, and other manifestations of differential rates of technological progress across industries. It is argued that the most important policy issues involve finding ways to make the currently lagging sectors more progressive, if in fact that can be done. Theory, to be useful, therefore must organize knowledge and guide research regarding what lies behind the uneven performance of the different economic sectors. In fact prevailing theory cannot do this, for two basic reasons. One is that theory is fragmented, and knowledge and research fall into a number of disjoint intellectual traditions. The second is that the strongest of the research traditions that bear on the differential innovation puzzle, research by economists organized around trying to ‘fit’ production functions and explain how production functions ‘shift’, neglects two central aspects of the problem; that innovation involves uncertainty in an essential way, and that the institutional structure supporting innovation varies greatly from sector to sector. The bulk of the paper is concerned with sketching a theoretical structure that appears to bridge a number of presently separate subfields of study of innovation, and which treats uncertainty and institutional diversity centrally.     

Benefits of collaborative action research for the beginning teacher

Beginning teachers are confronted with many issues as they begin their teaching careers, issues, such as classroom management, individual differences, behaviour problems, dealing with parents, and so on. Many beginning teachers take professional development seminars in an attempt to deal with these and other issues. Professional development seminars, however, may not address the specific issues faced by beginning teachers but rather focus on approaches that are more global. In this paper, we argue that the best approach to professional development is through a collaborative action research model. By extending the partnerships established between student teachers, mentor teachers and university supervisors during student teaching into the beginning teachers' career, many of the everyday problems can be confronted within a supportive network. Several recommendations are offered for beginning and maintaining productive CAR relationships.     

The logic of appropriability: From Schumpeter to Arrow to Teece

This note expounds the abstract fundamentals of the appropriability problem, re-assessing insights from three classic contributions—those of Schumpeter, Arrow and Teece. Whereas the first two contributions were explicitly concerned with the implications of appropriability for society at large, Teece's main concern was with practical questions of business strategy and economic organization. This note argues that, his practical concerns notwithstanding, Teece contributed, en passant but fundamentally, to the clarification of basic questions that previous authors had addressed less comprehensively and less satisfactorily. Specifically, his analysis of the innovator's access to complementary assets, undertaken from a contracting perspective, can be seen as filling a significant gap in the previous theoretical discussion of appropriability.     

History of Broadcasting

Philip T. Rosen, The Modern Stentors: Radio Broadcasting and the Federal Government, 1920-1934 (Westport,Conn.: Greenwood Press, 1980— $25.00).

Laurence Bergreen Look Now, Pay Later: The Rise of Network Broadcasting (New York: Doubleday, 1980 with paperback reprint by Mentor Books, 1981—$14.95/ 3.95).

C. Joseph Pusateri, Enterprise in Radio: WWL and the Business of Broadcasting it America (University Press of America, 4720 Boston Way, Lanham, Md. 20801— $19.50/11.75)

Alex McNeil, Total Television: A Comprehensive Guide to Programming from 1948 to 1980 (New York: Penguin Books, $9.95, paper)