Imaging of transient structures using nanosecond in situ TEM

The microstructure and properties of a material depend on dynamic processes such as defect motion, nucleation and growth, and phase transitions. Transmission electron microscopy (TEM) can spatially resolve these nanoscale phenomena but lacks the time resolution for direct observation. We used a photoemitted electron pulse to probe dynamic events with "snapshot" diffraction and imaging at 15-nanosecond resolution inside of a dynamic TEM. With the use of this capability, the moving reaction front of reactive nanolaminates is observed in situ. Time-resolved images and diffraction show a transient cellular morphology in a dynamically mixing, self-propagating reaction front, revealing brief phase separation during cooling, and thus provide insights into the mechanisms driving the self-propagating high-temperature synthesis.     

Homology similarity analysis of sequences of lactoferricin and its derivatives

A new method, homology similarity analysis (HSA), was developed to investigate homology pattern similarities of selected segments within sequences of peptides. This new approach facilitated elucidation of the structure-function relationships of lactoferricin derivatives. Helix propensity of positions 4-9 in the lactoferricin sequence was the most important in determining the antimicrobial activity of lactoferricin against Escherichia coli, followed by cationic charge pattern at positions 4-9 and 1-3. The pattern similarity of segments within sequences could be a useful tool for representing the distribution attributes of amino acid residue properties to the structure-function relationships of proteins and peptides, especially when used in conjunction with principal component similarity analysis followed by the regression version of artificial neural networks.     

Globalisation and income growth promote the Mediterranean diet

OBJECTIVE: To examine global food demand patterns and how changing diets may stimulate demand for and trade of Mediterranean diet products. DESIGN: Literature review. Trends in global and US food consumption patterns are examined and trade data are reviewed to evaluate the impact of changing diets on trade of Mediterranean diet products. Market access issues are also addressed briefly to highlight the role of policy in the trade of Mediterranean diet products. RESULTS: Diets are shifting towards higher-value products such as meats, fruits and vegetables, and a wider array of packaged food products. Trade in these products has also grown in the past two decades, with several non-traditional importers and exporters becoming increasingly active in the global market. CONCLUSIONS: Income-driven demands for quality and variety are likely to increase the demand for Mediterranean diet products globally. While the middle-income countries appear to be the best growth prospects, the USA remains a potential growth market if these products can meet the growing consumer demand for variety, quality and convenience. Although consumer trends globally indicate growth in demand for Mediterranean diet products, the additional demand may not be reflected by a corresponding growth in trade. Trade in Mediterranean diet products continues to be hampered by higher than average trade barriers and high transportation costs for perishables.     

Politics and Gender: Negotiating Conceptions of the Ideal Woman in Present Day Cambodia

This paper briefly describes a Khmer politician’s references to four women made during a 1993 campaign speech. It then reviews notions of the ideal woman from Khmer literature, and from life stories and ethnographic accounts. The politician manipulated gender symbolism, playing on multiple ambiguous notions of femaleness to prove his own powerful status and to comment on the current state of the Khmer social and moral order. In the face of the drastic changes of the last twenty years, he linked his own power and that of other men to their control over women’s sexuality. While he was willing to allow for, indeed participate in playing on, the ambiguity inherent in gender conceptions to create new ideal types of strong women, he simultaneously used appeals to tradition to maintain male authority over women.     

Pharmacokinetics of maropitant citrate after oral administration of multiple doses in adult horses

The neurokinin-1 (NK-1) receptor antagonist, maropitant citrate, mitigates nausea and vomiting in dogs and cats. Nausea is poorly understood in horses, and clinical use of NK-1 receptor antagonists has not been reported. This study aimed to determine the pharmacokinetics and safety of maropitant after administration of multiple doses. We hypothesized that maropitant concentrations would be similar at steady state to those reported in dogs, with minimal adverse effects. Maropitant was administered at 4 mg/kg orally, once daily for 5 days in seven adult horses. Serial plasma maropitant concentrations were measured by liquid chromatography-mass spectrometry. Noncompartmental pharmacokinetic parameters were determined. The maximum, minimum, and average concentrations of maropitant achieved at steady state were 375.5 ± 200, 16.8 ± 7.7, and 73.5 ± 45.1 ng/ml, respectively. The terminal elimination half-life was 11.6 ± 1.4 hr, and the accumulation index was 1.3 ± 0.07. Heart rate decreased between Day 1 and Day 5 (p = .005), with three horses having heart rates of 20 beats per minute and atrioventricular block on Day 5. Pharmacokinetics of repeated maropitant administration suggests the drug could be considered for use in healthy horses. Further investigation on the clinical relevancy of its cardiac effects is warranted.     

The value of marine ecological data collected by volunteers

Volunteers are potentially a huge scientific resource but there is scepticism among some scientists about the reliability of data collected by inexperienced people. An assessment was therefore made of the ability of a group of 13 volunteers, recruited by the Earthwatch Institute, to collect valid data in a project that aimed to map the distribution and abundance of common littoral organisms on shores of the Isle of Cumbrae, Scotland. The volunteers ranged considerably in age, educational background, knowledge and experience. They were capable of performing straight-forward tasks, such as learning to identify species, recording their occurrence on specific parts of the shore and making length measurements of samples of some gastropods. They made some recording errors during the fieldwork but similar errors were also made by experienced scientists and it is recommended therefore that all ecological studies should include quality control of data whether or not they involve volunteers. The assessment of abundance was problematic. Volunteers’ assessments for some species were inconsistent and there is evidence that individuals interpreted the scale in different ways. It is suggested that these problems stemmed from: (1) a lack of field experience in the volunteers; (2) inadequate guidelines on the use of the abundance scale; and (3) insufficient training before field surveys commenced. However, projects themselves may benefit in unexpected ways from the input of volunteers. They contributed taxonomic and computing skills to the current project. Members of the group also offered new insights by developing hypotheses relating to populations of gastropods during their fieldwork. These were tested and could have formed the basis of longer-term research programmes. There were also educational benefits for the volunteers who were involved in the project. These included increased knowledge of marine issues and clearer understanding of the ways in which scientific studies are undertaken.