203 research outputs found
A re-investigation of the path of carbon in photosynthesis utilizing GC/MS methodology. Unequivocal verification of the participation of octulose phosphates in the pathway
A GC/EIMS/SIM methodology has been developed to re-examine the path of carbon in photosynthesis. Exposing isolated spinach chloroplasts to (13)CO(2 )on a solid support for a defined period followed by quenching and work-up provided a mixture of labelled sugar phosphates. After enzymatic dephosphorylation and derivatization, the Mox-TMS sugars were analysed using the above method. The purpose of the study was to try to calculate the atom% enrichment of (13)C in as many of the individual carbons in each of the derivatized sugars as was practical using diagnostic fragment ions. In the event, only one 45 s experiment provided sufficient data to enable a range of enrichment values to be calculated. This confirmed that D-glycero-D-altro-octulose phosphate was present in the chloroplasts and was heavily labelled in the C4, C5 and C6 positions, in keeping with the hypothesis that it had an inclusive role and a labelling pattern consistent with a new modified pathway of carbon in photosynthesis
Wirtschaftspolitik und wirtschaftliche Aussichten in den Industrieländern
Der vorliegende Bericht, der neunte in dieser Reihe, ist das Ergebnis einer Konferenz unabhängiger Ökonomen aus Japan, Westeuropa und Nordamerika. Wie auch im letzten Jahr, stand die Wirtschaftspolitik, die in den Ländern dieser drei Regionen betrieben wurde, im Mittelpunkt der Gespräche. Die Konferenz fand vom 2. -4. November 1977 bei der Brookings Institution in Washington unter dem Vorsitz des Unterzeichneten statt und wurde vom Institut für Weltwirtschaft, dem Japan Economic Research Center und der Brookings Institution gefördert. Die wirtschaftspolitischen Ergebnisse dieser Tagung wurden in einer Pressemitteilung zusammengefaßt und veröffentlicht. Dieser Bericht gibt Auskunft über den Hintergrund, auf dem die wirtschaftspolitischen Empfehlungen zustande kamen. Der erste Abschnitt beschreibt die wirtschaftliche Entwicklung während des vergangenen Jahres in jeder der drei Regionen. Dabei wird der Tatsache Rechnung getragen, daß die wirtschaftliche Entwicklung dieser Länder sowohl Gemeinsamkeiten als auch Unterschiede aufweist. Anschließend wird ein Ausblick für das kommende Jahr gegeben, und die wechselseitigen Einflüsse zwischen den Regionen werden kurz untersucht. Danach folgt eine Diskussion jener Probleme, die in allen oder zumindest den meisten Ländern bestehen und einer befriedigenderen wirtschaftlichen Entwicklung im Wege stehen. Der Bericht endet mit der Darstellung der wirtschaftspolitischen Empfehlungen der Gruppe. Die Tagung und dieser Bericht wurden durch die Förderung durch den German Marshall Fund ermöglicht, dessen Präsident, Robert Gerald Livingston, der Konferenz beiwohnte. Die Teilnehmer der Konferenz, die die wirtschaftspolitischen Empfehlungen erarbeiteten, taten dies im eigenen Namen, nicht aber für die Institute, denen sie angehören. Dieser Bericht wird in Europa vom Institut für Weltwirtschaft, in Japan vom Japan Economic Research Center und in Nordamerika von der Brookings Institution publiziert. --
Diversity of Melissococcus plutonius from Honeybee Larvae in Japan and Experimental Reproduction of European Foulbrood with Cultured Atypical Isolates
European foulbrood (EFB) is an important infectious disease of honeybee larvae, but its pathogenic mechanisms are still poorly understood. The causative agent, Melissococcus plutonius, is a fastidious organism, and microaerophilic to anaerobic conditions and the addition of potassium phosphate to culture media are required for growth. Although M. plutonius is believed to be remarkably homologous, in addition to M. plutonius isolates with typical cultural characteristics, M. plutonius-like organisms, with characteristics seemingly different from those of typical M. plutonius, have often been isolated from diseased larvae with clinical signs of EFB in Japan. Cultural and biochemical characterization of 14 M. plutonius and 19 M. plutonius-like strain/isolates revealed that, unlike typical M. plutonius strain/isolates, M. plutonius-like isolates were not fastidious, and the addition of potassium phosphate was not required for normal growth. Moreover, only M. plutonius-like isolates, but not typical M. plutonius strain/isolates, grew anaerobically on sodium phosphate-supplemented medium and aerobically on some potassium salt-supplemented media, were positive for β-glucosidase activity, hydrolyzed esculin, and produced acid from L-arabinose, D-cellobiose, and salicin. Despite the phenotypic differences, 16S rRNA gene sequence analysis and DNA-DNA hybridization demonstrated that M. plutonius-like organisms were taxonomically identical to M. plutonius. However, by pulsed-field gel electrophoresis analysis, these typical and atypical (M. plutonius-like) isolates were separately grouped into two genetically distinct clusters. Although M. plutonius is known to lose virulence quickly when cultured artificially, experimental infection of representative isolates showed that atypical M. plutonius maintained the ability to cause EFB in honeybee larvae even after cultured in vitro in laboratory media. Because the rapid decrease of virulence in cultured M. plutonius was a major impediment to elucidation of the pathogenesis of EFB, atypical M. plutonius discovered in this study will be a breakthrough in EFB research
Overview of the PALM model system 6.0
In this paper, we describe the PALM model system 6.0. PALM (formerly an abbreviation for Parallelized Largeeddy Simulation Model and now an independent name) is a Fortran-based code and has been applied for studying a variety of atmospheric and oceanic boundary layers for about 20 years. The model is optimized for use on massively parallel computer architectures. This is a follow-up paper to the PALM 4.0 model description in Maronga et al. (2015). During the last years, PALM has been significantly improved and now offers a variety of new components. In particular, much effort was made to enhance the model with components needed for applications in urban environments, like fully interactive land surface and radiation schemes, chemistry, and an indoor model. This paper serves as an overview paper of the PALM 6.0 model system and we describe its current model core. The individual components for urban applications, case studies, validation runs, and issues with suitable input data are presented and discussed in a series of companion papers in this special issue
Direct effects of diazepam on emotional processing in healthy volunteers
RATIONALE: Pharmacological agents used in the treatment of anxiety have been reported to decrease threat relevant processing in patients and healthy controls, suggesting a potentially relevant mechanism of action. However, the effects of the anxiolytic diazepam have typically been examined at sedative doses, which do not allow the direct actions on emotional processing to be fully separated from global effects of the drug on cognition and alertness. OBJECTIVES: The aim of this study was to investigate the effect of a lower, but still clinically effective, dose of diazepam on emotional processing in healthy volunteers. MATERIALS AND METHODS: Twenty-four participants were randomised to receive a single dose of diazepam (5 mg) or placebo. Sixty minutes later, participants completed a battery of psychological tests, including measures of non-emotional cognitive performance (reaction time and sustained attention) and emotional processing (affective modulation of the startle reflex, attentional dot probe, facial expression recognition, and emotional memory). Mood and subjective experience were also measured. RESULTS: Diazepam significantly modulated attentional vigilance to masked emotional faces and significantly decreased overall startle reactivity. Diazepam did not significantly affect mood, alertness, response times, facial expression recognition, or sustained attention. CONCLUSIONS: At non-sedating doses, diazepam produces effects on attentional vigilance and startle responsivity that are consistent with its anxiolytic action. This may be an underlying mechanism through which benzodiazepines exert their therapeutic effects in clinical anxiety
Enhanced Visual Temporal Resolution in Autism Spectrum Disorders
Cognitive functions that rely on accurate sequencing of events, such as action planning and execution, verbal and nonverbal communication, and social interaction rely on well-tuned coding of temporal event-structure. Visual temporal event-structure coding was tested in 17 high-functioning adolescents and adults with autism spectrum disorder (ASD) and mental- and chronological-age matched typically-developing (TD) individuals using a perceptual simultaneity paradigm. Visual simultaneity thresholds were lower in individuals with ASD compared to TD individuals, suggesting that autism may be characterised by increased parsing of temporal event-structure, with a decreased capability for integration over time. Lower perceptual simultaneity thresholds in ASD were also related to increased developmental communication difficulties. These results are linked to detail-focussed and local processing bias
Loss of STOP Protein Impairs Peripheral Olfactory Neurogenesis
International audienceIn conclusion, STOP protein seems to be involved in the establishment of synapses in the olfactory glomerulus. Our results indicate that the olfactory system of STOP null mice is a well-suited experimental model (1) for the study of the mechanism of action of STOP protein in synaptic function/plasticity and (2) for pathophysiological studies of the mechanisms of altered neuronal connections in schizophrenia
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