Estimating genetic relationships among historical sources of alfalfa germplasm and selected cultivars with sequence related amplified polymorphisms

Fifteen alfalfa populations consisting of six public cultivars and nine historically recognized sources of alfalfa germplasm in North American cultivars were examined using sequence related amplified polymorphisms (SRAPs). Three bulk DNA samples from each population were evaluated with fourteen different SRAP primer pairs. This resulted in 249 different amplicons, of which over 90% were polymorphic. A dendrogram from the analysis suggests that the public cultivars are quite diverse from all the historical sources of germplasm. The highest mean genetic similarity among the nine original sources of Medicago germplasm was 0.85 between PI 536535 (Peruvian) and 536536 (Indian), while the lowest (0.47) was between PI 560333 (M. falcata) and 536539 (African). The highest mean genetic similarity among the nine original sources of Medicago germplasm and the public alfalfa cultivars was 0.78 between PI 536532 (Ladak) and Vernal, while the lowest (0.59) was between PI 536539 (African) and Oneida. Relationships based on SRAP analysis appear to generally concur with expected relationships based on fall dormancy. This report demonstrates that SRAPs are a promising marker system for detecting polymorphisms in alfalfa.     

The stability of soft drinks intake from adolescence to adult age and the association between long-term consumption of soft drinks and lifestyle factors and body weight

OBJECTIVES: To investigate the tracking of sugar-sweetened, carbonated soft drinks intake from age 15 to 33 years and the association between this intake and lifestyle factors and body weight. DESIGN: A longitudinal study with 18-20 years of follow-up. Data about diet, physical activity, smoking and dieting were collected in 1981/1979, 1991 and 1999. Body weight and height were measured in 1981/1979 and self-reported in 1999. SETTING: Oslo, Norway. SUBJECTS: Four hundred and twenty-two men and women. RESULTS: Tracking of soft drinks intake from adolescence into early adulthood (age 25 years) and from early adulthood into later adulthood (33 years) was moderate to high, while tracking from adolescence into later adulthood was low. Comparing those reporting a high intake of soft drinks in both 1991 and 1999 with those reporting a low intake at both times, male long-term high consumers were more likely to smoke (48 vs. 21%, P=0.002) and reported higher intakes of energy (12.2 vs. 10.2 MJ day(-1), P=0.005) and sugar (142 vs. 50 g day(-1), P<0.001) in 1999 than did long-term low consumers. Women high consumers were less likely to be physically active (14 vs. 42%, P=0.03) and had higher sugar intake (87 vs. 41 g day(-1), P<0.001) in 1999 than did women low consumers. There were no differences in body mass index, overweight or obesity in 1999 between long-term high and low consumers. CONCLUSION: In this study, stability of soft drinks intake from age 15 to 25 years and from age 25 to 33 years was moderate to high, while from age 15 to 33 years it was low. Soft drinks intake from age 25 to 33 years was associated with smoking and physical inactivity, but not with body weight.     

Monitoring fish stocks in relation to acidification in Norwegian watersheds

The Norwegian Monitoring Programme for Long-Range Transported Air Pollutants started in 1980. The biological part of this programme includes besides invertebrate studies in streams, (i) fish community status in lakes by means of interviews, test-fishing in lakes by using standard gill-net series, recruitment studies of brown trout in inland streams, and juvenile stock assess and monitoring of fish kills in salmon rivers. Damaged fish stocks are recognized within a land area of 51,500 km² in southern Norway and 30 km² in northern Norway. At least 6,000 lake-dwelling fish stocks have either been lost or are at various stages of reduction. Brown trout (Salmo trutta) is the most widespread and abundant species of fish in Norwegian watersheds, and is also most severe affected by acidification. More recently, there are some indications of an increase in the abundance of brown trout in some areas. However, analysis of age structure in lakes, and fry densities in streams in such areas revealed large annual variations in recruitment rate, which indicates unstable water chemical conditions. Atlantic salmon (Salmo salar) is virtually extinct in 25 rivers in southernmost, southwestern and western Norway.     

Fatty acid composition of various ectomycorrhizal fungi and ectomycorrhizas of Norway spruce

Whole cell fatty acid (WCFA) compositions of three different structures of ectomycorrhizal (ECM) fungi: sporocarps, pure culture mycelia and ectomycorrhizas were analysed to evaluate the potential use of fatty acid profiles as biomarkers for ECM fungi and ectomycorrhiza-associated bacteria. Sporocarps of Amanita muscaria, Amanita rubescens, Lactarius rufus, Lactarius thejogalus, Leccinum scabrum, Paxillus involutus, Russula foetens, Russula rosea, Russula vesca, Suillus grevillei, Tylopilus felleus, Xerocomus badius, Xerocomus subtomentosus, pure cultures of A. muscaria, P. involutus, X. badius, X. subtomentosus, Suillus bovinus Suillus luteus and seven ectomycorrhizal morphotypes of Norway spruce were examined. Our results revealed species-specific composition of fatty acids of fungal sporocarps and pure culture mycelia. Ectomycorrhizal morphotypes distinguished and identified by morphological and molecular methods (PCR-RLFP and sequencing) created specific fatty acid profiles. The dominating fatty acids in pure cultures and sporocarps were 18:2ω6,9, 18:1ω9 and 16:0, whereas ectomycorrhizas also contained plant and bacterial specific fatty acids. Especially, fatty acids specific to Gram-positive bacteria 15:0 anteiso and 17:0 anteiso were present in relatively high amounts and suggested that these bacteria are dominating in the examined Norway spruce mycorrhizosphere. In conclusion, our results show that fatty acid based methods can be useful in studies of ectomycorrhizal fungi, both as a quick method for differentiation of fungal species and also in studies of mycorrhiza-associated microorganisms in the field.     

Interactions between the external mycelium of the mycorrhizal fungus Glomus intraradices and other soil microorganisms as affected by organic matter

The influence of organic matter on the interactions between external mycelium of the arbuscular mycorrhizal (AM) fungus Glomus intraradices, the bacterium Burkholderia cepacia and other soil microorganisms was studied in a root-free sand environment. Organic matter amendment, in terms of ground barley leaves, markedly increased the growth of the external mycelium of G. intraradices as estimated both with the fatty acid biomarker 16:1ω5 and hyphal length measurements. Mycelial proliferation of G. intraradices in sand with organic matter was unaffected by both inoculation with B. cepacia and a soil filtrate containing a mixed population of indigenous microorganisms. On the other hand, in the absence of organic matter, both inoculation with B. cepacia and the soil filtrate reduced the growth of G. intraradices, as estimated with measurements of 16:1ω5. In contrast, B. cepacia inoculation increased hyphal length density of G. intraradices in the absence of organic matter. Overall, the presence of external mycelium of G. intraradices increased the bacterial biomass and counteracted a suppressive effect of B. cepacia on the growth of saprotrophic fungi.     

Breast-feeding at 12 months of age and dietary habits among breast-fed and non-breast-fed infants

OBJECTIVE: To analyse factors associated with breast-feeding and use of sweetened drinks at 12 months, and to compare dietary habits among breast-fed and non-breast-fed infants. DESIGN: Data were collected by a semi-quantitative food-frequency questionnaire filled in by the parents. SETTING: National dietary survey in Norway. SUBJECTS: In total, 1932 12-month-old infants were included. RESULTS: At 12 months, 36% of the infants were breast-fed. The odds of breast-feeding at this age were more than doubled both for mothers > or =35 years compared with mothers <25 years and for mothers in the highest educational group compared with mothers in the lowest. A negative association was found for maternal smoking, and the odds of breast-feeding were 40% lower for mothers who smoked than for non-smokers. Some dietary differences were observed between breast-fed and non-breast-fed infants apart from intake of milk. In particular, breast-fed infants had a significantly lower daily intake of sweetened drinks than non-breast-fed infants and a 16% lower mean daily intake of added sugars (P<0.001). Furthermore, breast-fed infants had 30% higher odds of not receiving sweetened drinks daily, compared with non-breast-fed infants. CONCLUSIONS: Maternal age, education and smoking status were important factors for breast-feeding at 12 months. Breast-fed infants had lower intakes of sweetened drinks and added sugars than non-breast-fed infants. From a public health perspective, continued promotion of breast-feeding is needed to reduce inequalities in breast-feeding. Moreover, prevention of high intakes of sweetened drinks and added sugars should start in infancy.     

Reinventing rural development in Vietnam: Discursive constructions of grassroots democracy during the renovation reform

Over the past decades Vietnam has seen striking efforts to reinvent the exercise of democratic rural development. Promotion of grassroots democracy, notably under the Grassroots Democracy Decree (GDD), has been an acute response by Communist Party and government to large scale unrest among the rural populace owing to dissatisfactions with a felt mismatch between espoused commitments to ‘good governance’ and its actual practice. Through evidence from field work, this paper assesses the implications of the GDD in the central and northern highlands, analyzing how the promotion of grassroots democracy is discursively constructed by rural development professionals. The results outline three dominant discourses, which center on their respective interests in liberalist democratization, improved efficiency in state renovation, and enhanced accountability in governing local policy ambiguities. It argues that ‘grassroots democracy’ is serving as a conceptual mediator, supporting learning between diverging interests associated with rural development and different ideological positions shrouding the notion of democracy itself. Yet, given the extent that discourses are reflective of how professionals relate to grassroots aspirations, grassroots movements, which originally ushered the Party and central government to pass the GDD, have a significant struggle ahead of them to affect concrete changes in professionals' practices.     

Empirical Explorations of SYNCHEM

During the past several years, a substantial body of experience has accumulated in the use of SYNCHEM, a large-scale program which is able to discover synthesis routes for relatively complex organic structures without on-line guidance on the part of its chemist user. These results indicate that the approach to computer-directed organic synthesis route discovery embodied in the program has been valid and reasonable, and that SYNCHEM is likely to be fruitful from the point of view of its intended users as well as for our research objectives in artificial intelligence. The experiments have revealed a number of insufficiencies in the program as well. Most of these are rectified in SYNCHEM2, a revised version of the program which includes, among other improvements, a more highly developed synthesis search algorithm and the routine consideration of stereochemistry.     

G protein betagamma subunit-mediated presynaptic inhibition: regulation of exocytotic fusion downstream of Ca2+ entry

The nervous system can modulate neurotransmitter release by neurotransmitter activation of heterotrimeric GTP-binding protein (G protein)-coupled receptors. We found that microinjection of G protein betagamma subunits (Gbetagamma) mimics serotonin's inhibitory effect on neurotransmission. Release of free Gbetagamma was critical for this effect because a Gbetagamma scavenger blocked serotonin's effect. Gbetagamma had no effect on fast, action potential-evoked intracellular Ca2+ release that triggered neurotransmission. Inhibition of neurotransmitter release by serotonin was still seen after blockade of all classical Gbetagamma effector pathways. Thus, Gbetagamma blocked neurotransmitter release downstream of Ca2+ entry and may directly target the exocytotic fusion machinery at the presynaptic terminal.