2,764 research outputs found
Studies in carboniferous bryozoa
Morphological investigations of some British Carboniferous bryozoan taxa has allowed aspects of their palaeobiology and systematics to be revised. Forty-one taxa, representing seventeen genera of nine families in the extinct Palaeozoic orders Cryptostomata, Fenestrate, Trepostomata and Cystoporata, are redescribed. Lectotypes have been established wherever necessary. Three new species are described and holotypes have been selected for these. Ordinal, familial and generic assignments have been made and diagnoses emended. Significant aspects of ordinal, familial and generic morphological characters have been discussed. Skeletal ultrastructures have been analysed in most forms studied and the function of a number of morphological characters has been reviewed. Evidence of the double walled concept of growth in the four extinct stenolaemate order have been reviewed. Extensive quantitative studies have allowed precise assessment of taxa, and the accurate definition and quantification of some unusual aspects of skeletal morphology, notably in Rhabdomeson rhombifera (Phillips). Combined with the quantitative studies there are extensive photographs and illustrations of the new and redescribed taxa. Geological ranges have been established for all taxa described
Predicting sexual problems in women: The relevance of sexual excitation and sexual inhibition
This is the post-print version of the article. The official published version can be obtained from the link below.Data from a non-clinical sample of 540 heterosexual women were used to examine the relationships between scores on the Sexual Excitation/Sexual Inhibition Inventory for Women (SESII-W) and ratings of current sexual problems, lifetime arousal difficulty, lifetime orgasm difficulty, and lifetime problems with low sexual interest. Multiple regression analyses also included several demographic/background variables as predictors: age, full-time employment, completed college, children in household, married, health ratings, importance of sex, and whether the woman was in a sexual relationship. The strongest statistical predictors of both current and lifetime sexual problems were the SESII-W inhibition factors Arousal Contingency and Concerns about Sexual Function. Demographic factors did not feature largely in any of the models predicting sexual problems even when statistically significant relationships were found. If future research supports the predictive utility of the SESII-W in identifying women who are more likely to experience sexual difficulties, these scales may be used as prognostic factors in treatment studies.This study was funded, in part, by a grant from the Lilly Centre for Women's Health
The Application of LANDSAT Data from Collection Platforms and LANDSAT Imagery for Fire Management, Everglades National Park, Florida
There are no author-identified significant results in this report
Extraction and measurement of adenosine triphosphate from marine sediment, The
Includes bibliographical references (pages 479-480).A technique has been developed, using boiling sodium bicarbonate buffer, to extract adenosine triphosphate (ATP) from marine sediments and has been tested on a variety of sediments, including those with high organic content, clay, and carbonate. Recovery of ATP, as measured by the addition of bacteria of known ATP content to sediment, varied from 64-100%. The technique also was as effective as the conventional Tris buffer for extraction of ATP from both pure cultures of bacteria grown in broth and natural seawater samples.Publisher version: http://www.jstor.org/stable/2835285
Regional differences in lectin binding patterns of vestibular hair cells
Surface glycoconjugates of hair cells and supporting cells in the vestibular endorgans of the bullfrog were identified using biotinylated lectins with different carbohydrate specificities. Lectin binding in hair cells was consistent with the presence of glucose and mannose (CON A), galactose (RCA-I), N-acetylgalactosamine (VVA), but not fucose (UEA-I) residues. Hair cells in the bullfrog sacculus, unlike those in the utriculus and semicircular canals, did not stain for N-acetylglucosamine (WGA) or N-acetylgalactosamine (VVA). By contrast, WGA and, to a lesser extent, VVA, differentially stained utricular and semicircular canal hair cells, labeling hair cells located in peripheral, but not central, regions. In mammals, WGA uniformly labeled Type 1 hair cells while labeling, as in the bullfrog, Type 2 hair cells only in peripheral regions. These regional variations were retained after enzymatic digestion. We conclude that vestibular hair cells differ in their surface glycoconjugates and that differences in lectin binding patterns can be used to identify hair cell types and to infer the epithelial origin of isolated vestibular hair cells
Scientific Visualization Using the Flow Analysis Software Toolkit (FAST)
Over the past few years the Flow Analysis Software Toolkit (FAST) has matured into a useful tool for visualizing and analyzing scientific data on high-performance graphics workstations. Originally designed for visualizing the results of fluid dynamics research, FAST has demonstrated its flexibility by being used in several other areas of scientific research. These research areas include earth and space sciences, acid rain and ozone modelling, and automotive design, just to name a few. This paper describes the current status of FAST, including the basic concepts, architecture, existing functionality and features, and some of the known applications for which FAST is being used. A few of the applications, by both NASA and non-NASA agencies, are outlined in more detail. Described in the Outlines are the goals of each visualization project, the techniques or 'tricks' used lo produce the desired results, and custom modifications to FAST, if any, done to further enhance the analysis. Some of the future directions for FAST are also described
Dynamics of the magnetic and structural a -> e phase transition in Iron
We have studied the high-pressure iron bcc to hcp phase transition by
simultaneous X-ray Magnetic Circular Dichroism (XMCD) and X-ray Absorption
Spectroscopy (XAS) with an X-ray dispersive spectrometer. The combination of
the two techniques allows us to obtain simultaneously information on both the
structure and the magnetic state of Iron under pressure. The magnetic and
structural transitions simultaneously observed are sharp. Both are of first
order in agreement with theoretical prediction. The pressure domain of the
transition observed (2.4 0.2 GPa) is narrower than that usually cited in
the literature (8 GPa). Our data indicate that the magnetic transition slightly
precedes the structural one, suggesting that the origin of the instability of
the bcc phase in iron with increasing pressure is to be attributed to the
effect of pressure on magnetism as predicted by spin-polarized full potential
total energy calculations
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The use of needs assessment methodologies to focus technical interventions in root and tuber crop post-harvest systems: a case study to improve incomes and reduce losses associated with marketing of fresh cassava from rural areas to Dar es Salaam
The Transfer of Needs Assessment Methodologies and Post-Harvest Technologies for Non-Grain Starch Staple Food Crops (NGSS) in sub-Saharan Africa project was initiated in Tanzania in July 1993 as a collaborative venture between the Natural Resources Institute (NRI) and the Tanzania Food and Nutrition Centre (TFNC). The project was funded by the UK Department For International Development (DFID). The main project involved activities in Ghana and Tanzania but this report deals exclusively with activities in Tanzania focusing on the transfer of needs assessment methodologies, the application of needs assessment in identifying post-harvest problems and technical interventions for NGSS and the identification, validation and dissemination of a technology to improve incomes and reduce post-harvest losses associated with marketing of fresh cassava roots from rural production areas to urban markets in Dar es Salaam.
In the first stage of the project a range of needs assessment methodologies were successfully validated under field conditions through the mechanism of three case studies, which were carried out in Lake Zone, Tanga Region and Dar es Salaam of Tanzania. Following the case studies, two training in needs assessment workshops were conducted in Tanzania to disseminate needs assessment technologies to key personnel from research organisations and institutes in Tanzania, Mozambique, Uganda, Kenya, Ghana, Rwanda and Ethiopia.
The needs assessment case study in Tanga Region highlighted post-harvest problems as a major constraint facing farmers and traders involved in the marketing of fresh cassava to urban areas, and formed the basis for a more detailed study of the marketing system for fresh cassava from rural production areas to urban markets in Dar es Salaam. Semi structured interviews with key stakeholders in the marketing system demonstrated that reductions in quality resulting from poor handling and delays in marketing lead to serious reductions in income throughout the market chain. Farmers and market personnel identified the criteria for a technical intervention to reduce income losses incurred when marketing fresh cassava.
After considering various options a simple low cost storage technique for fresh cassava originally developed by the Centro Internacional de Agricultura Tropical (CIAT) and NRI and later modified with DFID RNRRS funds by the NRI and the Ministry of Food and Agriculture (MoFA) in Ghana was selected for validation in Tanzania. Validation exercises in Tanzania demonstrated that low cost fresh cassava root storage technology had the technical and economic potential to alleviate postharvest problems associated with marketing of fresh cassava and improve the incomes of those involved in the cassava market system.
In the final stage of the project a flexible dissemination strategy was developed and used to carry out a limited technical dissemination campaign in the major cassava markets in Dares Salaam and selected villages ofKisarawe and Ruf~i Districts in Pwani (Coast) Region, and to promote wider awareness of the technology throughout Tanzania. Needs assessment techniques were used to develop practical approaches for dissemination and two impact assessments (November 1996 and December1997)
were carried out to assess effectiveness of dissemination activities and allow for optimisation ofthe strategy.
The first impact assessment (November 1996) was used to highlight the strengths and limitations of the initial dissemination strategy, so that a more effective strategy could be developed in collaboration with representatives of the Agricultural Extension Services and key stakeholders in the market system. In December 1997 a second impact assessment was made to assess the effectiveness of the revised dissemination strategy and to highlight any problems. The wider awareness campaign was found to have been effective and a number of expressions of interest had been received from organisations and individuals interested in fresh cassava within Tanzania.
A high level of interest and awareness was found in markets and villages where training activities had taken place, but a number of problems were identified which were hampering uptake of the technology. The two main problems were: (a). to be effective the technology needs to be implemented at all points in the market system but individuals were unwilling to take the risk ofbeing the first to use the technology without proof of the economic benefits of the technology; (b). the market system is dominated by a large open type of package called a lumbesa which is not suitable for application of the technology or for transport of cassava but is used for other reasons related to transport charges.
To overcome the first difficulty the project team developed a marketing demonstration to provide a practical demonstration of the financial benefits of low cost :fresh cassava root storage technology to potential beneficiaries within the marketing system. The second difficulty was addressed by representatives of various village governments and market co-operatives in collaboration with the TFNCINRI project team. In November of 1997 the village governments of Jaribu and Bungu villages in Rufiji District enacted bylaws to encourage adoption of close packaging for cassava and adoption of the new storage technology. To support this initiative the Agricultural Extension Service in Rufiji District have agreed to integrate the technology into their extension programmes, and in addition the village government in Jaribu has initiated its own training programme in the sub-villages around Jaribu. In December 1997 the village governments of Masaki, Sungwi and Gumba villages in Kisarawe District villages decided to follow the lead taken by villages in Rufiji District and develop bylaws and training programmes to promote uptake ofthe new technology. The Agricultural Extension Service for Kisarawe District have acknowledged the importance of cassava as a source of income generation in the District, and have agreed to integrate the technology into their extension programmes. If co-operation between the various stakeholders is maintained it seems likely that the technology will start to be adopted during 1998.
This case study within the main regional Africa project has demonstrated not only that low cost :fresh cassava root storage technology has the technical and economic potential to reduce post-harvest losses and improve incomes, but has also shown that key stakeholders are genuinely interested in adoption of the technology and are willing to co-operate and spend their own funds to promote uptake of the technology.
However, for successful uptake of the technology a wider dissemination at both local and national level is required. It is also clear that lack of funds in rural areas could constrain producers and country buyers from adopting this technology. To meet the needs ofthose involved in marketing of fresh cassava throughout Tanzania a sustained campaign of dissemination is required, involving close collaboration between the Agricultural Extension Services, selected NGOs and key stakeholders involved in marketing of fresh cassava from rural areas to various urban centres in Tanzania. A concept note for wider dissemination of low cost fresh cassava root storage technology in Tanzania is included in this report (Appendix 5).
The fmdings of this case study have shown that successful adoption of this technology would improve the quality of cassava reaching urban consumers, and contribute to poverty alleviation by improving the income generating potential of marketing of fresh cassava
Element-specific detectors for high pressure liquid chromatography (HPLC): a computerized, automated HPLC-graphite furnace atomic absorption system
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