Embryo induction and plant regeneration from cultured anthers and pistils of orchardgrass (Dactylis glomerata)

Direct embryogenesis was observed from Dactylis glomerata L. [orchardgrass (2N=4X=28)] anthers incubated at 25 C for 6 weeks on Schenk and Hildebrandt (SH) medium containing 3% sucrose and 30 pM dicamba [SH-30 (3,6 dichloro-o-anisic acid)]. Subsequent experi-ments showed that SH-30 supplemented with up to 5.0 g/1 casein hydro- lysate did not affect and 0.1 to 5.0 mg/1 benzylaminopurine or kinetin hindered the embryogenic response. Furthermore, anther orientation had no significant effect on the embryogenic response and no embryos were obtained from culture of isolated microspores. However, SH-30 containing 94 sucrose promoted embryogenesis and an anther density of 10/ml initiated more embryos per anther than the 100 anthers/ml treatment. Anthers initiated embryo-like structures from within micro- spores after culture on SH-30 for 6 weeks at 4 C. In another experi-ment, anthers were exposed to 0, 3, or 6 week cold pretreatments (4 C) and then cultured at 25 C on SH medium containing 0, 10, 20, or 30 pM dicamba and 9% sucrose. Embryo initiation was affected by an interaction of cold pretreatment and dicamba concentration. Stereomicroscopy showed that the 6 week cold pretreated anthers initi-ated indirect embryos from callus masses derived from microspores. Five of six plants regenerated from the 6 week cold pretreated anthers consisted of cells with 28 chromosomes. However, 1 plant had 14, 28, and up to 112 chromosomes and 1 to 8 nucleoli per nucleus. Direct embryogenesis was observed from ovary and style regions of unpollinated pistils cultured on SH-30 for 3 to 4 weeks at 25 C. After 5 and 6 weeks culture, however, embryos disorganized and produced calli which proliferated into numerous secondary embryos. An upright pistil orientation initiated a significantly greater embryo- genic response compared to those pistils cultured flat on the medium. All examined plants regenerated from pistil culture possessed the somatic chromosome number of 28 except for 1 mixoploid with 14, 28, and 56 chromosomes. Culture of excised unpollinated ovules failed to initiate any embryos when cultured on SH-30 with or without kinetin concentrations up to 5.0 mg/1. However, 1 of 60 ovules excised from pistils cultured for 3 weeks on SH-30 and then recultured on SH-30 initiated callus and embryos. Histology of pistils cultured for 3 weeks showed possible cell divisions within the embryo sac

Social networks of friendship in the writings of early medieval english women

Communities of women is a topic in Early Medieval English Studies that has largely been overlooked unless it's researched and discussed in the context of men, marriage, and religion. One obstacle that has prevented scholarship from researching and discussing communities of women outside of patriarchal and religious contexts is the continued focus on male-authored texts. Even though scholarship has progressed towards more feminist readings of the corpus, there is still a problem of which primary sources scholars choose to use as the focus of their feminist arguments. Female-composed texts of this period are often overlooked, are used as references for larger arguments about male-authored texts, or are discussed within male-centered contexts even if those arguments have a feminist lens. On the path to discovering women's perspectives in the corpus, I found that a majority of the sources composed by women were historical documents. These documents include wills and correspondence composed by women and lawsuit records that document the actions of women and their perspectives. These historical documents exhibit rhetorical features that express women's value of social networking, drive to maintain social networks, and desire to form new networks with other women. The main argument presented in this dissertation contends that early medieval English women formed social networks, in some cases friendships, with other women in order to maintain productive networks of women that yielded preservation of their properties and assets, emotional communion with one another, and protection of their persons

Sleep and affect in Old English poetry

A long-standing topic of discussion in Anglo-Saxon Studies has been the definition and conceptualization of the mind and mental activities in Anglo-Saxon literature and culture. Most recently, the discussion has circulated around what Antonina Harbus terms "the life of the mind," what Britt Mize calls the "poetics of mentality," and what Leslie Lockett designates as "the hydraulic model of the mind." In tandem with these cognitive approaches to Old English poetry are considerations of the connections between the mind and affect, and the mind and dreams. What is overlooked, though, and what is the primary topic of this research, is the concept and function of sleep in Old English poetry. In particular, I am interested in how the Anglo-Saxons conceptualized the process of sleep and what connection there is between sleep and affect. Moreover, I contend that sleep is an active and productive process whereby the influence of affect produces dreams

Tissue Culture of the Forage Grass Little Bluestem (Schizachyrium scoparium (Michx) Nash)

Little bluestem, Schizachyrium scomarium (Michx) Nash, a warm-season perennial native grass, is widely distributed over the temperate portion of North America (Hitchcock, 1971), extending from Quebec to Alberta and Southward to Florida and Arizona. It is a major upland component of the tall and mixed grass prairies and furnishes substantial amounts of palatable forage throughout the summer. Little bluestem has also been used for soil conservation purposes and its reseeding characteristic makes it especially useful in range and conservation plantings. Although the plant can be propagated vegetatively by dividing crowns, due to its bunch-type growth, the conventional way of propagation as such is not efficient. In the previous research conducted in this laboratory, segments of young inflorescences of some forage grass species were explanted onto a modified MS medium supplemented with 2, $-D and initiated calluses. After subcultured on the basal medium with auxin removed, the calluses differentiated into numerous somaclone plantlets (Chen, Stenberg and Ross, 1977; Chen, Lo and Ross, 1979; Lo, Chen and Ross, 1980). Such methods of rapid cloning would considerably shorten a breeding program. Another aspect of grass tissue culture research is focused on induction of mutations. Since most forage grass plants are heterozygous due to natural cross-fertilization and self-incompatability, desirable recessive characteristics are likely masked by the dominant genes. Induction of recessive mutations from the allelic dominant genes would uncover the desirable traits. Mutation treatment cells in vitro followed by induction of plant regeneration from these cells would be more accurate in obtaining homozygous recessive plants. However, plant regeneration in callus embryos, which are of single cell origin and genetically homogenous, or the development of shoots, which according to Wang and Vasil (1982), might be reorganized by many existing cells in the callus tissue. In the latter case, genetical heterogeneity, which would be obstructive to in vitro mutation studies, would result. In this research, the method previously used in cloning of forage grasses in this laboratory was applied to culture little bluestem. The calluses grown on the morphogenetic medium were histologically investigated to determine the pattern of differentiation

3,3'-Selenobis(propionic acid)

In contrast to Se[CH2C(O)OH]2 versus S[CH2C(O)OH](2), the title compound, Se[CH(2)CH(2)C(O)OH]2 or C6H10O4Se, is structurally quite similar to its sulfur analogue. The molecule has twofold symmetry. The C-Se-C bond angle is 96.48 (8) degrees and the Se-C bond lengths are 1.9610 (14) Å. The shortest SeO intermolecular distance is 3.5410 (11) Å. The  OO distances in the carboxylic acid dimers are 2.684 (2) Å. The temperature dependence of the IR spectrum suggests tautomerism in the solid state. Formula: C6H10O4S

The decentralisation-centralisation dilemma: recruitment and distribution of health workers in remote districts of Tanzania

<p>Abstract</p> <p>Background</p> <p>The implementation of decentralisation reforms in the health sector of Tanzania started in the 1980s. These reforms were intended to relinquish substantial powers and resources to districts to improve the development of the health sector. Little is known about the impact of decentralisation on recruitment and distribution of health workers at the district level. Reported difficulties in recruiting health workers to remote districts led the Government of Tanzania to partly re-instate central recruitment of health workers in 2006. The effects of this policy change are not yet documented. This study highlights the experiences and challenges associated with decentralisation and the partial re-centralisation in relation to the recruitment and distribution of health workers.</p> <p>Methods</p> <p>An exploratory qualitative study was conducted among informants recruited from five underserved, remote districts of mainland Tanzania. Additional informants were recruited from the central government, the NGO sector, international organisations and academia. A comparison of decentralised and the reinstated centralised systems was carried out in order to draw lessons necessary for improving recruitment, distribution and retention of health workers.</p> <p>Results</p> <p>The study has shown that recruitment of health workers under a decentralised arrangement has not only been characterised by complex bureaucratic procedures, but by severe delays and sometimes failure to get the required health workers. The study also revealed that recruitment of highly skilled health workers under decentralised arrangements may be both very difficult and expensive. Decentralised recruitment was perceived to be more effective in improving retention of the lower cadre health workers within the districts. In contrast, the centralised arrangement was perceived to be more effective both in recruiting qualified staff and balancing their distribution across districts, but poor in ensuring the retention of employees.</p> <p>Conclusion</p> <p>A combination of centralised and decentralised recruitment represents a promising hybrid form of health sector organisation in managing human resources by bringing the benefits of two worlds together. In order to ensure that the potential benefits of the two approaches are effectively integrated, careful balancing defining the local-central relationships in the management of human resources needs to be worked out.</p

Assessing performance enhancing tools: experiences with the open performance review and appraisal system (OPRAS) and expectations towards payment for performance (P4P) in the public health sector in Tanzania

Background Health workers’ motivation is a key determinant of the quality of health services, and poor motivation has been found to be an obstacle to service delivery in many low-income countries. In order to increase the quality of service delivery in the public sector in Tanzania, the Open Performance Review and Appraisal System (OPRAS) has been implemented, and a new results-based payment system, Payment for performance (P4P) is introduced in the health sector. This article addresses health workers’ experiences with OPRAS, expectations towards P4P and how lessons learned from OPRAS can assist in the implementation of P4P. The broader aim is to generate knowledge on health workers’ motivation in low-income contexts. Methods A qualitative study design has been employed to elicit data on health worker motivation at a general level and in relation to OPRAS and P4P in particular. Focus group discussions (FGDs) and in-depth interviews (IDIs) have been conducted with nursing staff, clinicians and administrators in the public health sector in a rural district in Tanzania. The study has an ethnographic backdrop based on earlier long-term fieldwork in Tanzania. Results Health workers evaluated OPRAS and P4P in terms of the benefits experienced or expected from complying with the tools. The study found a general reluctance towards OPRAS as health workers did not see OPRAS as leading to financial gains nor did it provide feedback on performance. Great expectations were expressed towards P4P due to its prospects of topping up salaries, but the links between the two performance enhancing tools were unclear. Conclusions Health workers respond to performance enhancing tools based on whether the tools are found appropriate or yield any tangible benefits. The importance placed on salary and allowances forms the setting in which OPRAS operates. The expected addition to the salary through P4P has created a vigorous discourse among health workers attesting to the importance of the salary for motivation. Lessons learned from OPRAS can be utilized in the implementation of P4P and can enhance our knowledge on motivation and performance in the health services in low-income contexts such as Tanzania.publishedVersio

Do health systems delay the treatment of poor children? A qualitative study of child deaths in rural Tanzania.

Child mortality remains one of the major public-health problems in Tanzania. Delays in receiving and accessing adequate care contribute to these high rates. The literature on public health often focuses on the role of mothers in delaying treatment, suggesting that they contact the health system too late and that they prefer to treat their children at home, a perspective often echoed by health workers. Using the three-delay methodology, this study focus on the third phase of the model, exploring the delays experienced in receiving adequate care when mothers with a sick child contact a health-care facility. The overall objective is to analyse specific structural factors embedded in everyday practices at health facilities in a district in Tanzania which cause delays in the treatment of poor children and to discuss possible changes to institutions and social technologies. The study is based on qualitative fieldwork, including in-depth interviews with sixteen mothers who have lost a child, case studies in which patients were followed through the health system, and observations of more than a hundred consultations at all three levels of the health-care system. Data analysis took the form of thematic analysis. Focusing on the third phase of the three-delay model, four main obstacles have been identified: confusions over payment, inadequate referral systems, the inefficient organization of health services and the culture of communication. These impediments strike the poorest segment of the mothers particularly hard. It is argued that these delaying factors function as 'technologies of social exclusion', as they are embedded in the everyday practices of the health facilities in systematic ways. The interviews, case studies and observations show that it is especially families with low social and cultural capital that experience delays after having contacted the health-care system. Reductions of the various types of uncertainty concerning payment, improved referral practices and improved communication between health staff and patients would reduce some of the delays within health facilities, which might feedback positively into the other two phases of delay