Microwave Power Transmission Workshop summary

The assumptions, methodologies, and conclusions of the NASA SPS studies were assessed and criticized to identify critical issues and to make recommendations for follow-on works. An assessment of the following items was made: beam forming and control, microwave amplifiers, radiating elements, and the rectenna. It was concluded that top priority should be given to determining an upper limit for permissible microwave power density which can be sent through the ionosphere

Education for citizenship: the Joseph Rowntree Charitable Trust and the educational settlement movement

No abstract available

The effects of storage conditions on viability of Clostridium difficile vegetative cells and spores and toxin activity in human faeces

AIMS: Clostridium difficile is a common nosocomial pathogen and as such diagnostic and research methods may necessitate storage of faecal specimens for long periods, followed by subsequent re-examination. This study investigated the effects of storage conditions upon the viability of this organism and its toxin. METHODS: Three genotypically distinct strains of C difficile (two clinical isolates including the UK epidemic strain, and an environmental isolate) were grown anaerobically at 37°C for 72 hours in a pool of five faecal emulsions. Aliquots of each emulsion were stored at either -20°C (frozen) or 4°C (refrigerated). Emulsions were assayed for viable cells, spores, and cytotoxin titre before storage and at days 1, 3, 5, 7, 14, 28, and 56. An aliquot of each emulsion was also removed, assayed, and replaced in storage at each time point to investigate the effects of multiple freezing/refrigeration/thawing . RESULTS: Neither storage temperature nor multiple cycles of refrigeration/freezing and thawing adversely affected the viability of C difficilevegetative cells or spores. Single and multiple exposures of samples to 4°C had little effect upon the C difficile toxin titre. Toxin titres of multiply frozen and thawed faeces became significantly lower than for refrigerated faeces (p < 0.01) by day 5 of the experiment in two of the three strains, and in all strains by day 28. Toxin titres of singly frozen faeces became significantly lower than for refrigerated faeces (p < 0.01) by day 56 of the experiment in two of the three strains. CONCLUSION: Storage temperature and multiple cycles of freezing (refrigeration)/thawing had minimal effects upon the viability of C difficile or its spores. Storage at 4°C has no discernible effect on C difficile cytotoxin. However, storage at -20°C has a detrimental effect upon C difficile cytotoxin, and multiple cycles of freezing and thawing may further adversely effect toxin titres

Brain food for babies

How does a mother supply a key building block of the brain required for neurodevelopment to her fetus in pregnancy? The critical requirement of docosahexaenoic acid (DHA) for fetal brain development, and the poor efficiency of its synthesis in humans, is a tricky metabolic problem to be overcome in pregnant women. Supplying this unique fatty acid to the fetus requires exquisite specificity and timing, processes that can unravel in disease conditions such as pre-eclampsia

Maternal plasma docosahexaenoic acid (DHA) concentrations increase at the critical time of neural tube closure

No abstract available

The Challenges Posed by Globalization for Economic Liberalization in Two Asian Transitional Countries: Laos and Vietnam

globalization backlash, foreign direct investment, East Asia