Mechanical properties of lettuce

The fracture properties of Spanish Iceberg and English Round lettuce tissues were investigated using a tensile test on notched specimens. The level of notch sensitivity was investigated for samples of differing colour and vein orientation. Vein orientation perpendicular to the test direction proved to be the most notch sensitive and samples with vein orientation parallel to the test direction proved to be very notch insensitive, samples with a diagonal (45°) orientation showed an intermediate response. This response was interpreted in terms of the interaction of veins with the crack path. The strengths of English Round tissues were broadly comparable with those of Spanish Iceberg although the upper limits depended on vein orientation and were in the order: parallel > diagonal perpendicular. A similar ranking of vein orientation was found in estimates of stiffness.     

Synthesis and structure of the tetradeca-iron(III) oxide–alkoxide cluster [Bu4N]2[Fe14O8(OCH2CH3)20Cl8]

The iron(III) oxide–alkoxide cluster, di-tetra-n-butylammonium octachloro-tetra(μ₃-oxo)-tetra(μ₄-oxo)- icosa(μ₂-ethoxo)-tetradeca-iron(III), has been isolated and its X-ray crystal structure determined.     

Implementing a bespoke supply chain management system to deliver tangible benefits

Companies often focus efforts to improve business efficiencies on internal systems and significant benefits can be achieved by so doing. However, the magnitude of the realised benefit is restricted if only processes within the organisation are targeted for improvement. This paper describes the implementation of a bespoke web-based supply chain management system/online collaboration system. The main drivers behind the development of the system were late deliveries from the supplier and also sporadic and inaccurate delivery schedule information from the supplier. The implementation approach is discussed along with the problems that were encountered en route and the measures that were undertaken to ensure that implementation was successful. The importance of metrics is stressed, as these are essential if any improvements are to be quantified. The metrics enable justification of such projects in financial terms which is compounded by the ‘soft’ benefits that result from the use of such systems.     

Coupling human mobility and social ties

Studies using massive, passively collected data from communication technologies have revealed many ubiquitous aspects of social networks, helping us understand and model social media, information diffusion and organizational dynamics. More recently, these data have come tagged with geographical information, enabling studies of human mobility patterns and the science of cities. We combine these two pursuits and uncover reproducible mobility patterns among social contacts. First, we introduce measures of mobility similarity and predictability and measure them for populations of users in three large urban areas. We find individuals'' visitations patterns are far more similar to and predictable by social contacts than strangers and that these measures are positively correlated with tie strength. Unsupervised clustering of hourly variations in mobility similarity identifies three categories of social ties and suggests geography is an important feature to contextualize social relationships. We find that the composition of a user''s ego network in terms of the type of contacts they keep is correlated with mobility behaviour. Finally, we extend a popular mobility model to include movement choices based on social contacts and compare its ability to reproduce empirical measurements with two additional models of mobility.     

Cigarette smoking and other risk factors for silent cerebral infarction in the general population

Control dried organisms as lenticules are a dependable and convenient alternative to wet cultures for quality assurance and process controls in routine food microbiology. Lenticules are designed to give a fixed, reproducible inoculum over an extended period of time without loss of cultural characteristics or viability. During a period of 23 months, 596 paired counts were performed by both Miles and Misra and spiral plating techniques on lenticule controls. Correlation between the two methods and within batches was excellent. Only 14 counts (2.5%) fell outside the standard operating limit of 0.5 log10. All were within 1.0 log10. On two separate occasions, replicate runs were performed on five reconstituted lenticules from a batch. The counts obtained showed variation within and between lenticules only slightly in excess of what is expected by chance. Lenticule replicates performed by three other laboratories also produced satisfactory results. It is thought that lenticules could improve the accuracy of total plate counts and lead to a better standardization of quantitative methods in food microbiology within and between laboratories.     

Nitrous Oxide Emissions from a Fertilized and Grazed Grassland in the South East of Ireland

Agriculture currently accounts for 28% of national greenhouse gas emissions in Ireland. Nitrous oxide (N₂O) emissions from agricultural soils account for 38% of this total. A 2-year study was conducted, using the chamber technique on a fertilized and grazed grassland to quantify the effect of fertilizer application rate, soil and meteorological variables on N₂O emissions. Three N fertilizer regimes (0, 225 & 390 kg N ha⁻¹) were imposed with three replicates of each treatment. Nitrogen fertilizer was applied as urea (46% N) in spring with calcium ammonium nitrate (CAN-26% N) applied in the summer (June–September). Rotational grazing was practiced using steers. Nitrous oxide emissions arising from the unfertilized plots (0 N) were consistently low. Emissions from the N-fertilized plots (225 & 390 kg N ha⁻¹) were concentrated in relatively short periods (1–2 weeks) following fertilizer applications and grazing, with marked differences between treatments, relative patterns and magnitudes of emissions at different times of the year and between years. Variation in N₂O emissions throughout both years was pronounced with mean coefficients of variation of 116% in year 1 and 101% in year 2. The study encompassed two climatologically contrasting years. As a result the N₂O–N loss, as a percent of the N applied in the cooler and wetter 2002 (0.2–2.0%), were similar to those used for N-fertilized grasslands under the Intergovernmental Panel on Climate Change (IPCC) N₂O emission inventory calculation methodology (1.25% ± 1). In contrast, the percentage losses in the warmer and drier 2003 (3.5–7.2%) were substantially higher.     

音箱科学——音乐缪斯的供奉(下)

音箱和房间 如同扬声器振膜后方的空间(声箱)一样,其前方的空间也经常带来严重的问题.听音室是音响系统的最终一道环节,在音频重播的所有环节中,这也是音箱制造商最少把握或是根本没有把握的一环.设计出一种在房间内尽可能好声的音箱是十分重要的第一步.     

Earth Science Datacasting: Informed Pull and Information Integration

The intent of Datacasting is to empower consumers of Earth science data with the ability to extract from a stream of data granules (or files) precisely those granules that are required to meet a predefined need, for example, ldquoAcquire from a MODIS L2 data stream only the granules that contain information about a wild fire in Southern California.rdquo Our approach to solving this problem has been to take the concept of Really Simple Syndication (RSS) feeds, for delivering regularly changing web content, and extend this to represent a stream of data granules and deliver regularly changing Earth science data content. In essence, this project is doing for Earth science what Podcasting has done for audio and video. Where Podcasting extended RSS to revolutionize how users access audio and video content provided by various media outlets, so Datacasting extends RSS to provide users with the ability to download data granules provided by Earth science data providers as the data are made available. Moreover, we have taken the concept one step further by creating a solution for filtering on the metadata of a feed in order to identify granules of interest based on user-defined criteria. In this paper, we also show how Datacasting feeds can be combined with other RSS-based feeds to identify relationships between information sources and extract new knowledge, as well as aid the development of new geo-based web services not currently envisaged.