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Rapeseed is the oil-bearing seed from plants of the Brassica genus. It grows well in the cooler agricultural regions o f the world and for this reason has long been thought to be a promising crop for interior Alaska. Rapeseed has been grow n in India and China for thousands and in Europe for hundreds o f years (Bolton 1980). Its history in North America began in 1943 when a small quantity of seed was imported into Canada. In recent years, its production has been largely that from cultivars bred for production of seed low in erucic acid and glucosinolate content. Seed from these cultivars is referred to by the Canadian Rapeseed Industry as canola. Its qualities are desirable in the edible-oil market, the largest market for products from canola seed. Canada is now one of the world’s largest producers and is the world’s largest exporter o f rapeseed. The meal that remains after oil extraction is high in protein and is used as a supplement in livestock feeds. The whole seed can also be used as a feed supplement. Some cultivars o f rapeseed that are high in erucic acid are also grow n for use in plastics and industrial oils (Genser and Eskin 1979). In addition, forage rapeseed cultivars can be used as livestock pasture. Research concerning the production of rapeseed has been addressed by the Agricultural and Forestry Experiment Station (AFES) for several years. O f specific concern has been the selection of appropriate cultivars (Wooding et al. 1978), response to various nitrogen (N) rates, row spacings and seeding rates (Lewis and Knight 1987), performance in reduced-tillage systems in rotation with barley (Knight and Lewis 1986), the potential for frost seeding in late fall and early spring (Knight and Sparrow 1984) and response to boron (B) to enhance early seed ripening (Wooding 1985). In addition, in 1978 the Cooperative Extension Service (CES) began conducting seminars on production o f rapeseed for Alaskan farmers. In 1979 and 1980, CES employed Dr. J.L . Bolton, a rapeseed specialist from the University o f Alberta, in an extension capacity to give technical assistance to farmers on producing rapeseed (Bolton 1980)

On computation of the first Baues--Wirsching cohomology of a freely-generated small category

The Baues--Wirsching cohomology is one of the cohomologies of a small category. Our aim is to describe the first Baues--Wirsching cohomology of the small category generated by a finite quiver freely. We consider the case where the coefficient is a natural system obtained by the composition of a functor and the target functor. We give an algorithm to obtain generators of the vector space of inner derivations. It is known that there exists a surjection from the vector space of derivations of the small category to the first Baues--Wirsching cohomology whose kernel is the vector space of inner derivations.Comment: 11 page

Response to Crocetti et al.

No abstract available

The gastric acid pocket is attenuated in H. pylori infected subjects

Objective Gastric acid secretory capacity in different anatomical regions, including the postprandial acid pocket, was assessed in Helicobacter pylori positive and negative volunteers in a Western population. Design We studied 31 H. pylori positive and 28 H. pylori negative volunteers, matched for age, gender and body mass index. Jumbo biopsies were taken at 11 predetermined locations from the gastro-oesophageal junction and stomach. Combined high-resolution pH metry (12 sensors) and manometry (36 sensors) was performed for 20 min fasted and 90 min postprandially. The squamocolumnar junction was marked with radio-opaque clips and visualised radiologically. Biopsies were scored for inflammation and density of parietal, chief and G cells immunohistochemically. Results Under fasting conditions, the H. pylori positives had less intragastric acidity compared with negatives at all sensors >1.1 cm distal to the peak lower oesophageal sphincter (LES) pressure (p<0.01). Postprandially, intragastric acidity was less in H. pylori positives at sensors 2.2, 3.3 and 4.4 cm distal to the peak LES pressure (p<0.05), but there were no significant differences in more distal sensors. The postprandial acid pocket was thus attenuated in H. pylori positives. The H. pylori positives had a lower density of parietal and chief cells compared with H. pylori negatives in 10 of the 11 gastric locations (p<0.05). 17/31 of the H. pylori positives were CagA-seropositive and showed a more marked reduction in intragastric acidity and increased mucosal inflammation. Conclusions In population volunteers, H. pylori positives have reduced intragastric acidity which most markedly affects the postprandial acid pocket

Superluminal Signals: Causal Loop Paradoxes Revisited

Recent results demonstrating superluminal group velocities and tachyonic dispersion relations reopen the question of superluminal signals and causal loop paradoxes. The sense in which superluminal signals are permitted is explained in terms of pulse reshaping, and the self-consistent behavior which prevents causal loop paradoxes is illustrated by an explicit example.Comment: 6 pages, 3 figure

The effects of graded levels of calorie restriction : III. Impact of short term calorie and protein restriction on mean daily body temperature and torpor use in the C57BL/6 mouse

GRANT SUPPORT This work was supported by BBSRC BB009953/1 awarded to JRS and SEM. PK and CD were funded by the Erasmus exchange programme. JRS, SEM, DD, CG, LC, JJDH, YW, DELP, DL and AD are members of the BBSRC China Partnership Award, BB/J020028/1.Peer reviewedPublisher PD

Affective Man-Machine Interface: Unveiling human emotions through biosignals

As is known for centuries, humans exhibit an electrical profile. This profile is altered through various psychological and physiological processes, which can be measured through biosignals; e.g., electromyography (EMG) and electrodermal activity (EDA). These biosignals can reveal our emotions and, as such, can serve as an advanced man-machine interface (MMI) for empathic consumer products. However, such a MMI requires the correct classification of biosignals to emotion classes. This chapter starts with an introduction on biosignals for emotion detection. Next, a state-of-the-art review is presented on automatic emotion classification. Moreover, guidelines are presented for affective MMI. Subsequently, a research is presented that explores the use of EDA and three facial EMG signals to determine neutral, positive, negative, and mixed emotions, using recordings of 21 people. A range of techniques is tested, which resulted in a generic framework for automated emotion classification with up to 61.31% correct classification of the four emotion classes, without the need of personal profiles. Among various other directives for future research, the results emphasize the need for parallel processing of multiple biosignals

Dispersive properties of quasi-phase-matched optical parametric amplifiers

The dispersive properties of non-degenerate optical parametric amplification in quasi-phase-matched (QPM) nonlinear quadratic crystals with an arbitrary grating profile are theoretically investigated in the no-pump-depletion limit. The spectral group delay curve of the amplifier is shown to be univocally determined by its spectral power gain curve through a Hilbert transform. Such a constraint has important implications on the propagation of spectrally-narrow optical pulses through the amplifier. In particular, it is shown that anomalous transit times, corresponding to superluminal or even negative group velocities, are possible near local minima of the spectral gain curve. A possible experimental observation of such effects using a QPM Lithium-Niobate crystal is suggested.Comment: submitted for publicatio

A Knob for Changing Light Propagation from Subluminal to Superluminal

We show how the application of a coupling field connecting the two lower metastable states of a lambda-system can produce a variety of new results on the propagation of a weak electromagnetic pulse. In principle the light propagation can be changed from subluminal to superluminal. The negative group index results from the regions of anomalous dispersion and gain in susceptibility.Comment: 6 pages,5 figures, typed in RevTeX, accepted in Phys. Rev.