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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2009.04.047 Byline: Dale Muzzey (1)(4), Carlos A. Gomez-Uribe (1)(2), Jerome T. Mettetal (1), Alexander van Oudenaarden (1)(3) Keywords: SYSBIO; MICROBIO; SIGNALING Abstract: Negative feedback can serve many different cellular functions, including noise reduction in transcriptional networks and the creation of circadian oscillations. However, only one special type of negative feedback ('integral feedback') ensures perfect adaptation, where steady-state output is independent of steady-state input. Here we quantitatively measure single-cell dynamics in the Saccharomyces cerevisiae hyperosmotic shock network, which regulates membrane turgor pressure. Importantly, we find that the nuclear enrichment of the MAP kinase Hog1 perfectly adapts to changes in external osmolarity, a feature robust to signaling fidelity and operating with very low noise. By monitoring multiple system quantities (e.g., cell volume, Hog1, glycerol) and using varied input waveforms (e.g., steps and ramps), we assess in a minimally invasive manner the network location of the mechanism responsible for perfect adaptation. We conclude that the system contains only one effective integrating mechanism, which requires Hog1 kinase activity and regulates glycerol synthesis but not leakage. Author Affiliation: (1) Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA (2) Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA (3) Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA (4) Harvard University Graduate Biophysics Program, Harvard Medical School, Boston, MA 02115, USA Article History: Received 10 April 2008; Revised 22 January 2009; Accepted 13 April 2009 Article Note: (miscellaneous) Published: July 9, 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.01.013 Byline: Andrea Schievano, Giuliana D'Imporzano, Fabrizio Adani Abbreviations: ABP, anaerobic biogasification potential; ECs, energy crops; BRs, industrial and agro-industrial by-products and residues; AMs, animal manures; SM, swine manure; OW, organic waste; OFMSW, organic fraction of municipal solid waste; OS, olive oil sludge Abstract: In this study, industrial and agro-industrial by-products and residues (BRs), animal manures (AMs), and various types of organic wastes (OWs) were analyzed to evaluate their suitability as substitutes for energy crops (ECs) in biogas production. A comparison between the costs of the volume of biogas that can be produced from each substrate was presented with respect to the prices of the substrates in the Italian market. Furthermore, four different feeding mixtures were compared with a mixture of EC and swine manure (Mixture A) used in a full-scale plant in Italy. Swine manure is always included as a basic substrate in the feeding mixtures, because many of the Italian biogas plants are connected to farms. When EC were partially substituted with BR (Mixture B), the cost (0.28a[logical not]Nm.sup.-3) of the volume of biogas of Mixture A dropped to 0.18a[logical not]Nm.sup.-3. Furthermore, when the organic fraction of municipal solid waste (OFMSW) and olive oil sludge (OS) were used as possible solutions (Mixtures C and D), the costs of the volume of biogas were -0.20 and 0.11a[logical not]Nm.sup.-3, respectively. The negative price signifies that operators earn money for treating the waste. For the fifth mix (Mixture E) of the OFMSW with a high solid substrate, such as glycerin from biodiesel production, the resulting cost of the volume of biogas produced was -0.09a[logical not]Nm.sup.-3. By comparing these figures, it is evident that the biogas plants at farm level are good candidates for treating organic residues of both municipalities and the agro-industrial sector in a cost-effective way, and in providing territorially diffused electric and thermal power. This may represent a potential development for agrarian economy. Author Affiliation: Dipartimento di Produzione Vegetale, Universita degli Studi di Milano, Via Celoria 2, 20133 Milan, Italy Article History: Received 28 May 2008; Revised 19 December 2008; Accepted 21 January 2009

Byline: Erik Solligard (1), Ingebjorg S. Juel (2), Karin Bakkelund (2), Harald Johnsen (3), Ola D. Saether (2), Jon Erik Gronbech (2), Petter Aadahl (1) Keywords: Splanchnic circulation; Ischaemia-reperfusion injury; Permeability; Microdialysis; Glycerol; Lactic acid Abstract: Objective To evaluate the use of gut luminal microdialysis as a tool for monitoring ischaemic metabolites, particularly glycerol, as markers of intestinal dysfunction during and after intestinal ischaemia. Design A randomised, controlled animal experiment. Setting National laboratory animal centre. Interventions In seven pigs the thoracic aorta was cross-clamped for 60 min followed by 2 h of reperfusion, while five pigs served as controls. Measurements and results Glycerol, lactate and glucose in the intestinal lumen and mucosa were measured by microdialysis. Intestinal tissue blood flow was determined by means of colour-labelled microspheres. To assess intestinal permeability, 14.sup.C-polyethylene glycol 4000 (PEG-4000) was instilled in a jejunal segment and then measured in venous blood. Intestinal blood flow was reduced to 10% of baseline by aortic cross-clamping (p=0.001) and returned to baseline during reperfusion. Intestinal luminal lactate increased during ischaemia and further increased during reperfusion. The increase was paralleled by augmented intestinal permeability there was a significant correlation between luminal lactate and venous PEG-4000 (r=0.89, p Conclusion Microdialysis of lactate may be useful for monitoring intestinal ischaemia and reperfusion. Release of lactate into the intestinal lumen appears to be related to increased permeability. Intestinal luminal glycerol closely mirrored glycerol concentrations in the intestinal wall. Author Affiliation: (1) Department of Anaesthesiology and Intensive Care, St. Olav University Hospital, Norwegian University of Science and Technology, 7006, Trondheim, Norway (2) Department of Surgery, St. Olav University Hospital, Norwegian University of Science and Technology, 7006, Trondheim, Norway (3) Department of Laboratory Medicine, St. Olav University Hospital, Norwegian University of Science and Technology, 7006, Trondheim, Norway Article History: Registration Date: 08/01/2004 Received Date: 04/07/2003 Accepted Date: 30/12/2003 Online Date: 28/02/2004 Article note: Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00134-004-2173-0

The PCR and DNA dot blot analysis is used to screen numerous Lactobacillus species including strain RC-14 and determine the presence of the gene encoding the large subunit of glycerol dehydratase (gldC), the enzyme responsible for reuterin production. The findings from the probiotic effects of L. reuteri RC-14 revealed that the intestine and vagina are independent of reuterin production.

The new spiro[4.5]acetal okaspirodiol was isolated from Streptomyces sp. Go TS 19 as a secondary metabolite in yields up o 380 mg/L. The biosynthesis of spiro[4.5]acetal okaspirodiol was investigated by feeding experiments with [.sup.13.C]-labeled precursors proving its origin from a new type of the rare mixed acetate-glycerol biosynthetic pathway.

The dynamics of sorbitol/glycerol mixtures across the entire composition range has been characterized by dielectric relaxation measurements for frequencies between 10mHz and 10MHz. The gradual change in the glass transition temperature (Tg), fragility (m), nonexponentiality and occurrence of a secondary Johari-Goldstein type relaxation as a function of the mole fraction is explored.

Impact of glass transition, water and glycerol on sucrose inversion of pullulan-sucrose matter is examined.