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X-irradiated protoplasts of a Brassica napus line carrying the Ogura Raphanus sativus male sterile cytoplasm were fused to protoplasts of male fertile B. napus cv. Olga. Plants were regenerated from six out of 34 randomly selected clones. In one clone, Bn(RS)26, a plant with male sterile flowers was obtained. Mitochondria of this plant are non-parental as revealed by DNA-DNA hybridization using a species specific probe. Its chloroplasts, however, derive from the fertile parent which results in loss of the sensitivity to low temperatures associated with R. sativus plastids in the male sterile parent. The novel cytoplasm of the Bn(RS)26 cybrid was transmitted through seed.

Brassica cybrids were obtained after fusing protoplasts of fertile and cytoplasmic male sterile (CMS) B. napus lines carrying the original b. napus, and the Ogura Raphanus sativus cytoplasms, respectively. Iodoacetate treatment of the fertile line and X-irradiation of the CMS line prevented colony formation from the parental protoplasts. Colony formation, however, was obtained after protoplast fusion. Hybrid cytoplasm formation was studied in 0.5 g to 5.0 g calli grown from a fused protoplast after an estimated 19 to 22 cell divisions. Chloroplasts and mitochondria were identified in the calli by hybridizing appropriate DNA probes to total cellular DNA. Out of the 42 clones studied 37 were confirmed as cybrids. Chloroplast segregation was complete at the time of the study. Chloroplasts in all of the cybrid clones were found to derive from the fertile parent. Mitochondrial DNA (mtDNA) segregation was complete in some but not all of the clones. In the cybrids, mtDNA was different from the parental plants. Physical mapping revealed recombination in a region which is not normally involved in the formation of subgenomic mtDNA circles. The role of treatments used to facilitate the recovery of cybrids, and of organelle compatibility in hybrid cytoplasm formation is discussed.

Background Kenya has a high burden of maternal and newborn mortality. Consequently, the Government of Kenya introduced health system reforms to promote the availability of skilled birth attendants (SBAs) and proscribed deliveries by traditional birth attendants (TBAs). Despite these changes, only 10 % of women from pastoralist communities are delivered by an SBA in a health facility, and the majority are delivered by TBAs at home. The aim of this study is to better understand the practices and perceptions of TBAs and SBAs serving the remotely located, semi-nomadic, pastoralist communities of Laikipia and Samburu counties in Kenya, to inform the development of an SBA/TBA collaborative care model. Methods This descriptive qualitative study was undertaken in 2013–14. We conducted four focus group discussions (FGDs) with TBAs, three with community health workers, ten with community women, and three with community men. In-depth interviews were conducted with seven SBAs and eight key informants. Topic areas covered were: practices and perceptions of SBAs and TBAs; rewards and challenges; managing obstetric complications; and options for SBA/TBA collaboration. All data were translated, transcribed and thematically analysed. Results TBAs are valued and accessible members of their communities who adhere to traditional practices and provide practical and emotional support to women during pregnancy, delivery and post-partum. Some TBA practices are potentially harmful to women e.g., restricting food intake during pregnancy, and participants recognised that TBAs are unable to manage obstetric complications. SBAs are acknowledged as having valuable technical skills and resources that contribute to safe and clean deliveries, especially in the event of complications, but there is also a perception that SBAs mistreat women. Both TBAs and SBAs identified a range of challenges related to their work, and instances of mutual respect and informal collaborations between SBAs and TBAs were described. Conclusions These findings clearly indicate that an SBA/TBA collaborative model of care consistent with Kenyan Government policy is a viable proposition. The transition from traditional birth to skilled birth attendance among the pastoralist communities of Laikipia and Samburu is going to be a gradual one, and an interim collaborative model is likely to increase the proportion of SBA assisted deliveries, improve obstetric outcomes, and facilitate the transition.

Correction for heteroscedasticity in returns from portfolios long in small firms and short in large firms listed on the New York Stock Exchange reduces the estimate of market risk and increases the estimated abnormal return. Greatly improved diagnostic test statistics are obtained, strengthening the evidence for the existence of positive average abnormal returns from small firms. Periodicity of order 6 and 12 months is identified. The estimation procedure operates by exploiting the autoregressive pattern of heteroscedasticity in the return data.

1. The object of the computations described in this paper was to determine what effect a hypothetical reduction in military accompanied by a compensating increase in non-military demand would have on the industrial composition and regional distribution of employment in the continental United States. By compensation is meant the maintenance of the total level of employment in the economy. In a paper published four years ago,' inputoutput analysis was used to estimate the effect of such a change in the structure of final demand on the industrial distribution of the labor force for the country as a whole. The present study carries that inquiry one step further. The impact of the hypothetical shift from military to civilian demand is projected here not only in inter-industrial, but also in inter-regional terms. Specifically, the territory of the continental United States has been subdivided into 19 distinct regions, and the shift in the industrial composition of output and employment was assessed for each one of them. Had we attempted to study each region separately and then simply to add the results to arrive at corresponding aggregates for the country as a whole, the total national output figures and the corresponding total input figures for each distinct category of goods and services could not have been expected to match. In other words, the results of such isolated regional studies would not comprise a consistent picture of the national economy as a whole. The simple scheme of multi-regional analysis on which the present computations are based provides for simultaneous balancing of all inputoutput flows from the point of view of each individual region, as well as for the U.S. economy as a whole. For some goods let them be called Locala balance between production and consumption tends to be established separately within each region; for other goods let them be identified as National such a balance typically is achieved only for the country as a whole. Within each region the output of a National good might exceed or fall short of its total input, the deficit or surplus being evened out by exports to or imports from other regions. Retail Trade and Auto Repair Services are characteristically Local industries while Coal Mining and Aircraft Manufacturing are typically National. The difference between the two obviously should be explained in terms of the relative mobility or transportability of their output. To separate National industries from the Local, all sectors were arranged in order of the increasing magnitude of inter-regional, as compared with the intra-regional, trade of their respective products. Then, an admittedly somewhat arbitrary cut was made across that array, setting apart the Local industries, serving mainly users located within the region in which production occurs, from the National industries, supplying the entire national or even international market, whose products typically are being shipped for this reason in comparatively large amounts across regional lines.2 * All authors were members of the Harvard Economic Research Project. This study was financed by the National Science Foundation and the Rockefeller Foundation. The computations were performed on the IBM 7094 at the Harvard Computing Center. 'Wassily Leontief and Marvin Hoffenberg, "The Economic Effect of Disarmament," Scientific American, April 1961. 2The concluding observations at the end of this article describe a possible refinement of this approach which introduces a graduated distinction between National, Regional and Sub-regional industries and goods.