Production of lipids with Microchloropsis salina in open thin-layer cascade photobioreactors.

Microalgal biomass is considered as the most promising feedstock for sustainable production of liquid fuels. Lipid production with Microchloropsis salina was studied in open thin-layer cascade (TLC) photobioreactors with a surface area of 8 m2 applying a physically simulated Mediterranean summer climate. High lipid concentrations of up to 6.6 g L-1 with 46% (w w-1) total lipids in dry cell mass were achieved in two-phase batch processes applying a nitrogen limitation. The two-phase batch process was transferred into a continuously operated reactor cascade of two TLC photobioreactors. Microchloropsis salina cells were produced continuously in the first photobioreactor, whereas continuous lipid production was enabled in the second, nitrogen-limited TLC photobioreactor resulting in continuous production of 3.0 g L-1 lipids with a high overall lipid space-time-yield of 0.2 g L-1 d-1. The control of alkalinity to about 10 mM resulted in high CO2 conversion efficiencies of 84-87%.

Application of light-emitting diodes (LEDs) in cultivation of phototrophic microalgae: current state and perspectives.

The quality and regulation of the incident light is crucial in microalgae cultivation processes. Depending on wavelength, spectrum, and intensity, growth characteristics and biochemical composition of these organisms vary. With mainly fluorescent lamps (FL) used previously for illumination, such variabilities could not be studied adequately due to their broad emission spectrum. In contrast, light-emitting diodes (LEDs) emit a very narrow wavelength band and enable flexible photobioreactor designs due to their small size. This review provides a condensed overview on the application of LEDs in microalgal cultivation processes. It summarizes the current availability and applicability of LED technologies as an illumination source for research-focused photobioreactor systems. A particular focus is the use of narrow-wavelength LEDs to address fundamental as well as applied aspects of light color on algae biomass and value-added compound formation. In this respect, the application of internal and external illumination systems is reviewed together with trends in the industrial use of LED systems to intensify algae process efficiency.

Posatirelin for the treatment of degenerative and vascular dementia: results of explanatory and pragmatic efficacy analyses.

In order to confirm the efficacy and safety of posatirelin (L-pyro-2-aminoadipyl-L-leucyl-L-prolinamide), a synthetic peptide having cholinergic, catecholaminergic and neurotrophic activities, a multicentre, double-blind, controlled study versus placebo was planned in elderly patients suffering from Alzheimer's disease and vascular dementia, according to National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) and National Institute of Neurological Disorders and Stroke/Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria, respectively. The trial consisted of a 2-week run-in phase with placebo administered once a day orally, followed by a double-blind period of 3 months, with posatirelin or placebo administered once a day intramuscularly. Efficacy was assessed using the Gottfries-Bråne-Steen (GBS) Rating Scale (primary variable) and the Rey Memory Test (secondary variable). Laboratory tests, vital signs and adverse events were monitored. A total of 360 patients were randomized, the intent-to-treat sample (ITT) being made up of 357 patients and the per protocol sample (PP) of 260 patients. Both pragmatic and explanatory analyses showed significant differences between treatment groups in the GBS Rating Scale and the Rey Memory Test, with no difference in the two types of dementia. No difference between treatments was observed in safety variables, the incidence of adverse events in the posatirelin group being 7.3%. The study confirms previous results showing that treatment with posatirelin can improve cognitive and functional abilities of patients suffering from degenerative or vascular dementia.

Effects of a cable car trip on blood pressure and cardiovascular hormones in lowlander and highlander normotensives.

The effects of a cable car trip from 1370 m (4500 ft) to 3460 m (11350 ft) were studied in 6 lowlanders (3 men and 3 women, mean age 31 +/- 4 years, living at an altitude of less than 500 m) and in 10 highlanders (all males, mean age 37 +/- 12 years, ski teachers and cable car workers working for greater than or equal to 6 months/year at a greater than 3000 m). Cuff blood pressure (BP), heart rate, plasma catecholamines, serum renin, aldosterone, ACTH and cortisol were measured immediately before and 20 min after the trip, at rest and at the same air temperature. A handgrip test was also performed under the same conditions. At baseline, lowlanders and highlanders showed significant differences in diastolic BP (86 +/- 5 mmHg in lowlanders and 91 +/- 4 mmHg in highlanders, p = 0.05), plasma noradrenaline (323 +/- 114 pg/ml in lowlanders and 585 +/- 255 in highlanders, p less than 0.05), serum renin (10 +/- 6 pg/ml in lowlanders and 17 +/- 8 in highlanders, p less than 0.05), and serum cortisol (163 +/- 54 ng/ml in lowlanders and 120 +/- 25 in highlanders, p less than 0.01). The acute exposure to high altitude did not modify BP, heart rate or any of the measured cardiovascular hormones in either group. The handgrip test provoked a significant increase in systolic and diastolic BP in both lowlanders and highlanders (p less than 0.01), and this response was not modified by the change in altitude; however, highlanders showed significantly smaller increases in systolic BP than lowlanders at both altitudes (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)