Stability in Ecosystem Functioning across a Climatic Threshold and Contrasting Forest Regimes

Classical ecological theory predicts that changes in the availability of essential resources such as nitrogen should lead to changes in plant community composition due to differences in species-specific nutrient requirements. What remains unknown, however, is the extent to which climate change will alter the relationship between plant communities and the nitrogen cycle. During intervals of climate change, do changes in nitrogen cycling lead to vegetation change or do changes in community composition alter the nitrogen dynamics? We used long-term ecological data to determine the role of nitrogen availability in changes of forest species composition under a rapidly changing climate during the early Holocene (16k to 8k cal. yrs. BP). A statistical computational analysis of ecological data spanning 8,000 years showed that secondary succession from a coniferous to deciduous forest occurred independently of changes in the nitrogen cycle. As oak replaced pine under a warming climate, nitrogen cycling rates increased. Interestingly, the mechanism by which the species interacted with nitrogen remained stable across this threshold change in climate and in the dominant tree species. This suggests that changes in tree population density over successional time scales are not driven by nitrogen availability. Thus, current models of forest succession that incorporate the effects of available nitrogen may be over-estimating tree population responses to changes in this resource, which may result in biased predictions of future forest dynamics under climate warming

New Zealand blackcurrant extract enhances fat oxidation during prolonged cycling in endurance-trained females.

PURPOSE: New Zealand blackcurrant (NZBC) extract has previously been shown to increase fat oxidation during prolonged exercise, but this observation is limited to males. We examined whether NZBC intake also increases fat oxidation during prolonged exercise in females, and whether this was related to greater concentrations of circulating fatty acids. METHODS: In a randomised, crossover, double-blind design, 16 endurance-trained females (age: 28 ± 8 years, BMI: 21.3 ± 2.1 kg·m-2, VO2max: 43.7 ± 1.1 ml·kg-1·min-1) ingested 600 mg·day-1NZBC extract (CurraNZ™) or placebo (600 mg·day-1microcrystalline cellulose) for 7 days. On day 7, participants performed 120 min cycling at 65% VO2max, using online expired air sampling with blood samples collected at baseline and at 15 min intervals throughout exercise for analysis of glucose, NEFA and glycerol. RESULTS: NZBC extract increased mean fat oxidation by 27% during 120 min moderate-intensity cycling compared to placebo (P = 0.042), and mean carbohydrate oxidation tended to be lower (P = 0.063). Pre-exercise, plasma NEFA (P = 0.034) and glycerol (P = 0.051) concentrations were greater following NZBC intake, although there was no difference between conditions in the exercise-induced increase in plasma NEFA and glycerol concentrations (P > 0.05). Mean fat oxidation during exercise was moderately associated with pre-exercise plasma NEFA concentrations (r = 0.45, P = 0.016). CONCLUSIONS: Intake of NZBC extract for 7 days elevated resting concentrations of plasma NEFA and glycerol, indicative of higher lipolytic rates, and this may underpin the observed increase in fat oxidation during prolonged cycling in endurance-trained females

A spill over effect of entrepreneurial orientation on technological innovativeness:an outlook of universities and research based spin offs

partially_open5siBy shifting towards Romer’s (Am Econ Rev 94:1002–1037, 1986) economy and so the spread of knowledge economy, universities started to adopt a collaborative approach with their entrepreneurial ecosystem. They turn out to be risk taker, autonomous, proactive, competitive, and innovative. In a nutshell, they are entrepreneurial oriented with the aim to generate new innovative ventures, known as research-based spin offs. Doubly, this has induced an improvement of technology transfer and the degree of entrepreneurship in the current knowledge economy. However there still is a paucity of studies on the spill over effect of entrepreneurial orientated universities and research-based spin off on technology transfer need to be more explored. Therefore, the article investigates the link between entrepreneurial orientation and such spill overs by offering an outlook of two universities and two research-based spin offs in the United Kingdom. The scope is to provide a deep view of technological innovativeness in a research context, entrepreneurial oriented. Our research suggests that entrepreneurial attitude has become an imperative to succeed in the context where British institutions currently operate. Entrepreneurship brings the necessary technological innovation to the university and its students, which results in better positioning of the university at national and international levels, with the subsequent impact on their ability to attract not only new students and academics but also funding to conduct their research.openScuotto, Veronica; Del Giudice, Manlio; Garcia-Perez, Alexeis; Orlando, Beatrice; Ciampi, FrancescoScuotto, Veronica; Del Giudice, Manlio; Garcia-Perez, Alexeis; Orlando, Beatrice; Ciampi, Francesc

Cyanobacterial lipopolysaccharides and human health – a review

Cyanobacterial lipopolysaccharide/s (LPS) are frequently cited in the cyanobacteria literature as toxins responsible for a variety of heath effects in humans, from skin rashes to gastrointestinal, respiratory and allergic reactions. The attribution of toxic properties to cyanobacterial LPS dates from the 1970s, when it was thought that lipid A, the toxic moiety of LPS, was structurally and functionally conserved across all Gram-negative bacteria. However, more recent research has shown that this is not the case, and lipid A structures are now known to be very different, expressing properties ranging from LPS agonists, through weak endotoxicity to LPS antagonists. Although cyanobacterial LPS is widely cited as a putative toxin, most of the small number of formal research reports describe cyanobacterial LPS as weakly toxic compared to LPS from the Enterobacteriaceae. We systematically reviewed the literature on cyanobacterial LPS, and also examined the much lager body of literature relating to heterotrophic bacterial LPS and the atypical lipid A structures of some photosynthetic bacteria. While the literature on the biological activity of heterotrophic bacterial LPS is overwhelmingly large and therefore difficult to review for the purposes of exclusion, we were unable to find a convincing body of evidence to suggest that heterotrophic bacterial LPS, in the absence of other virulence factors, is responsible for acute gastrointestinal, dermatological or allergic reactions via natural exposure routes in humans. There is a danger that initial speculation about cyanobacterial LPS may evolve into orthodoxy without basis in research findings. No cyanobacterial lipid A structures have been described and published to date, so a recommendation is made that cyanobacteriologists should not continue to attribute such a diverse range of clinical symptoms to cyanobacterial LPS without research confirmation

Formation of a chiral center and pyrimidal inversion at the single-molecule level.

(Chemical Equation Presented) One-at-a-time stereochemistry: As-S bond-making and bond-breaking reactions are important in pharmacology, toxicology, and cell biology. The aqueous covalent chemistry of individual As III molecules can be monitored inside a protein nanoreactor. The approach is used to follow the creation of a chiral center at As III, through the formation of a short-lived As-S bond, and to monitor inversion at that center (see picture). © 2007 Wiley-VCH Verlag GmbH and Co. KGaA

Formation of a chiral center and pyrimidal inversion at the single-molecule level.

(Chemical Equation Presented) One-at-a-time stereochemistry: As-S bond-making and bond-breaking reactions are important in pharmacology, toxicology, and cell biology. The aqueous covalent chemistry of individual As III molecules can be monitored inside a protein nanoreactor. The approach is used to follow the creation of a chiral center at As III, through the formation of a short-lived As-S bond, and to monitor inversion at that center (see picture). © 2007 Wiley-VCH Verlag GmbH and Co. KGaA

North Atlantic forcing of Amazonian precipitation during the last ice age

The last glacial period was marked by multiple, abrupt reorganizations of ocean and atmosphere circulation. On thousand-year timescales, slowing of the Atlantic meridional overturning circulation was associated with cooling in the high northern latitudes, whereas strengthened circulation was linked to northern warming. In the tropics, these millennial-scale events were primarily reflected in altered patterns of precipitation. These hydrologic fluctuations induced ecological changes in the Atlantic seaboard and the high Andes, but less is known about the Amazon Basin. Here we reconstruct precipitation over Amazonian Ecuador over the past 94,000 years using a δ18O record from speleothems collected in Santiago Cave in western Amazonia. We interpret the variability of the δ18O record as changes in the source and amount of precipitation. With the exception of the period between 40,000 and 17,000 years ago, abrupt, high-frequency changes coincide with shifts in North Atlantic circulation, indicating a high-latitude influence on Amazonian precipitation over millennial timescales. On longer timescales, the record shows a relationship to precessional changes in the Earth’s orbit. In light of the lack of extreme aridity in our records, we conclude that ecosystems in western Amazonia have not experienced prolonged drying over the past 94,000 years