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Selective electrical stimulation of postganglionic cerebrovascular parasympathetic nerve fibers originating from the sphenopalatine ganglion enhances cortical blood flow in the rat

Recently, the origins and pathways of cerebrovascular acetylcholine- and vasoactive intestinal polypeptide-containing nerves have been elucidated in detail in the rat: The sphenopalatine ganglion is the major source for postganglionic parasympathetic fibers to the vascular beds of the cerebral hemispheres. To clarify the functional role of the nerves on cerebral blood vessels in vivo, brain cortic

The Evolution of Life Histories in Holo-anhydrobiotic Animals: A First Approach

The life histories of holo-anhydrobiotic animals differ from those of all other organisms by a regular or irregular entrance into an ametabolic state induced by desiccation. Such ametabolic periods will arrest growth and reproduction completely and thus affect primary life history parameters dramatically. The selective forces and the genetic and physiological trade-offs acting on anhydrobiotic ani

Rapidly rotating Bose-Einstein condensates in anharmonic potentials

Rapidly rotating Bose-Einstein condensates confined in anharmonic traps can exhibit a rich variety of vortex phases, including a vortex lattice, a vortex lattice with a hole, and a giant vortex. Using an augmented Thomas - Fermi variational approach to determine the ground state of the condensate in the rotating frame - valid for sufficiently strongly interacting condensates - we determine the tra

Energy-Centric Scheduling for Real-Time Systems

Energy consumption is today an important design issue for all kinds of digital systems, and essential for the battery operated ones. An important fraction of this energy is dissipated on the processors running the application software. To reduce this energy consumption, one may, for instance, lower the processor clock frequency and supply voltage. This, however, might lead to a performance degrada

A society With or Without Drugs : Continuity and change in Drug Policies in Sweden and the Netherlands

Popular Abstract in Swedish Sammanfattning I debatter och forskning om narkotikapolitik anges den svenska och nederländska modellen ofta som ett motsatspar. Såväl målet för, som utformningen av, narkotikapolitiken har framställts som radikalt olika. Detta synsätt kan sägas vara riktigt. Målet för den svenska narkotikapolitiken är att skapa ett narkotikafritt samhälle. Den nederländska strävar efteIn debates about the Swedish and Dutch drug policies are usually positioned as opposites. The goal for the Swedish drug policy is to create a 'drug-free society'; while in the Netherlands a harm reduction approach prevails. In this study a drug policy is considered a practice of formal social control that can develop differently depending on the contexts in which it emerged. The period studied sta

Holocene treeline history and climate change across northern Eurasia

Radiocarbon-dated macrofossils are used to document Holocene treeline history across northern Russia (including Siberia), Boreal forest development in this region commenced by 10,000 yr B.P, Over most of Russia, forest advanced to or near the current arctic coastline between 9000 and 7000 yr B.P. and retreated to its present position by between 4000 and 3000 yr B.P. Forest establishment and retrea

Prenylated isoflavanone from the roots of Erythrina sigmoidea

A novel prenylated isoflavanone, sigmoidin I, has been isolated from the roots of Erythrina sigmoidea, in addition to the known isoflavones, corylin and neobavaisoflavone and the known pterocarpan, phaseollidin. Its structure was established as 7,4'-dihydroxy-3'-methoxy-5'-(3-methylbut-2-enyl) isoflavanone by means of spectroscopic analyses and chemical transformations. Neobavaisoflavone displayed

A new Q-learning algorithm based on the Metropolis criterion

The balance between exploration and exploitation is one of the key problems of action selection in Q-learning. Pure exploitation causes the agent to reach the locally optimal policies quickly, whereas excessive exploration degrades the performance of the Q-learning algorithm even if it may accelerate the learning process and allow avoiding the locally optimal policies. In this paper, finding the o

Systems Thinking in Supply Chain Measurements

Both practitioners and research scientists have noted a number of problems regarding measurement activities during the past decade. The problems reported suggest that measurement activities are fragmented both within and across organizations. This article expands on a systems perspective on supply chain measurements and describes how problems can be communicated, understood and managed by developi

The measurement of cell growth in coal slurries

Microbial growth in coal slurries can be detected if surfactant is present in the samples by analysing the protein concentration after disintegration of the cells. Without surfactant present in the samples, the proteins are readily adsorbed on the coal surfaces. A suitable surfactant is sodium dodecyl sulphate at 0.5 to 1% of the sample volume

Characterization of eight barley xantha-f mutants deficient in magnesium chelatase

Magnesium chelatase (EC 6.6.1.1) catalyses the insertion of magnesium into protoporphyrin IX, the first unique step of the chlorophyll biosynthetic pathway. The enzyme is composed of three different subunits of approximately 40, 70 and 140 kDa. In barley (Hordeum vulgare L.) the subunits are encoded by the genes Xantha-h, Xantha-g and Xantha-f. In the 1950s, eight induced xantha-f mutants were iso