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1.
Summary Volatile carbonyl compounds of carrot varietyFeonia Hunderup S-64 at various stages of maturity were analysed as their 2,4-DNPH's by a combined TLC-GLC-MS method. Twenty-three different carbonyl compounds were identified, of which undecanal, buten-2-al, methylbutenal, pentan-2-one, 6-methyl-5-hepten-2-one and 5-methylfurfural have not previously been found in carrot. During maturation the content of acetaldehyde and acetone increased significantly, while that of methylbutenal decreased.
Die leichtflüchtigen Monocarbonylverbindungen der Karotten in verschiedenen Stufen der Reife
Zusammenfassung Die leichtflüchtigen Carbonylverbindungen der Karotten Varietät Feonia Hunderup S-64 wurden in verschiedenen Stufen der Reife als 2,4-DNPH mit der kombinierten DC-GC-MS-Methode analysiert. Dreiundzwanzig verschiedene Carbonylverbindungen wurden nachgewiesen. Von diesen sind Undecanal, 2-Butenal, Methylbutenal, 2-Pentanon, 6-Methyl-5-hepten-2-on und 5-Methylfurfural noch nicht in Karotten aufgefunden worden. Während des Reifens nahm der Gehalt an Acetaldehyd und Aceton bedeutend zu. Der Gehalt an Methylbutenal verminderte sich.
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2.
The anabolic effects of insulin are not restricted to carbohydrate and lipid metabolism but also include protein metabolism. However, the effects of insulin on protein metabolism have been difficult to demonstrate in vivo. Amino acid transport is partly regulated by insulin according to the experimental data. PET provides a way to measure fractional uptake rates of amino acids. The purpose of this study was to measure the effect of insulin on amino acid transport from the plasma to the human parotid glands. METHODS: We compared the uptake of L-[methyl-11C]methionine ([11C]methionine) into the parotid glands and cerebellum in seven healthy volunteers during the fasting state and euglycemic insulin clamp technique (1 mU/kg per minute). RESULTS: The fractional uptake rate of [11C]methionine was increased by 31% for the right parotid gland (p = 0.003) and by 29% for the left parotid gland (p = 0.009) during insulin clamp, while the increase was 19% for the cerebellum (p = 0.01). The concentration of amino acids typical for the hormone-sensitive transport system A was 11% lower during insulin infusion than in the fasting state. CONCLUSION: The uptake of methionine into brain tissue does not seem to be under major control by insulin, while the transport of methionine in the parotid glands is stimulated by insulin. PET provides a sophisticated method to study the transport system of amino acids in vivo.  相似文献   
3.
Summary Joint actions are introduced as a language basis for operational specification of reactive systems. Joint action systems are closed systems with no communication primitives. Their nondeterministic execution model is based on multi-party actions without an explicit control flow, and they are amenable for stepwise derivation by superposition. The approach is demonstrated by deriving a specification for serializable databases in simple derivation steps. Two different implementation strategies are imposed on this as further derivations. One of the strategies is two-phase locking, for which a separate implementation is given and proved correct. The other is multiversion timestamp ordering, for which the derivation itself is an implementation. Reino Kurki-Suonio received a Dr. Phil. degree from the University of Helsinki in 1964. At the University of Tampere he headed the first computer science department in Scandinavia since its creation in 1965. Currently he is professor of computer science and engineering at Tampere University of Technology. He has held visiting positions at Carnegie-Mellon and Stanford Universities. During the years his research interests have shifted from formal grammars, parsing methods, and programming languages to formal specification and design of distributed systems.  相似文献   
4.
Wildfire burnt forest biomass can be salvaged as feedstock for bioenergy power generating stations. Despite availability of such forest biomass in northwestern Ontario, its procurement has generally been considered uneconomic and no studies have looked into the cost of harvesting, processing, and transporting the burnt material for bioenergy production. In order to meet the demand of biomass for proposed and existing power generating stations using renewable fuels, a standard costing model is used to determine the feasibility of procuring biomass from burnt areas using a full-tree to roadside, roadside grinder to mill system. The case-study was conducted at the Hogarth Plantations near Thunder Bay, Ontario, Canada. The total cost incurred for processing and delivery of biomass from wildfire burnt area with a hauling distance of 7 km and total trip cycle time of 2.55 h was found to be $29.65 gt?1, with net energy content of 11.4 GJ gt?1. The total procurement cost depends on the hauling distance and a linear relationship between the two was established. The energy analysis found a net energy output to input ratio of 35:1 for the operation.  相似文献   
5.
Superconductivity in a LaOFeAs system is known to get introduced by F-doping (LaO1−x F x FeAs) even under ambient conditions and oxygen deficiency (LaO1−x FeAs) under high pressure conditions. Hitherto unreported, superconductivity in F-free undoped LaOFeAs samples is observed and confirmed for the first time by various characterization tools–resistive ρ(T,B), magnetic M(T,B) and modulated microwave absorption (MMA) measurements. The ρ(T) at B=0 shows a clear superconducting transition with an onset at T con∼17 K and a tail-like behavior when R goes to zero at T c0∼8 K. In the presence of B, the superconducting transition shifts to lower T with a rate ∼−5.5 and −1.65 T/K, depending on whether the ρ(T) has dropped to 90% or 5% of its normal state value, respectively. M(T) in zero field cooling at B=10 mT shows diamagnetic downturn below at ∼12 K. At T<T c0 the change in MMA with B shows a low field (B∼1 mT) peak, which vanishes at T>T c0, indicating the presence of weak link superconducting networks in the sample. The sample shows a complex electrical and magnetic behavior in the normal state. For instance, ρ(T) reveals a weak SDW-like anomaly at T∼132 K along with a resistivity minimum at T min ∼78 K. M(T) also shows the presence of a magnetic anomaly at T∼130 K. Both below and above T con, presence of an additional ferromagnetic component is observed in the isothermal M(B) loop measurements. The superconducting and normal state features of our sample are compared with other undoped and doped LaOFeAs systems reported in the literature.  相似文献   
6.
Numerical simulation techniques are used to investigate the frequency dependence of the noise of the hysteretic rf SQUID up to frequencies on the order ofR/L. An exact lower bound for the noise of the instrument is given as a function of the parameters of the SQUID ring, pump frequency, and the temperature. This result is compared with the predictions of a scaling argument and with experiment.  相似文献   
7.
Strongyloides stercoralis infection is of low prevalence in Malaysia. We report an unusual case presenting primarily with gastric symptoms. The patient was a 72 years old Chinese male admitted for progressive weight loss and abdominal bloating. Gastroscopic examination revealed mucosal prepyloric elevations in the gastric mucosa. Gastric strongyloidiasis was confirmed by the presence of adult forms, as well as ova and larval rhabditiform stages of the worm in the gastric mucosal crypts. We believe that this is the first histologically documented case of gastric strongyloidiasis in Malaysia.  相似文献   
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9.
Spatial audio is a field that investigates techniques to reproduce spatial attributes of sound (e.g., direction, distance, width of sound sources, and room envelopment) to the listener. Such attributes cannot be reproduced accurately with one loudspeaker, therefore two-channel stereophony was introduced, later extended to different surround formats having five to eight loudspeakers. An even more accurate reproduction of spatial attributes can be achieved with loudspeaker setups often found in theaters and in some public venues, which contain a large number of loudspeakers around listeners, possibly also above and/or below them.  相似文献   
10.
Theoretical and experimental studies of the ignition of forest combustible materials by real ignition sources, which are modeled by a reference source, are reported. The time of ignition by the reference source is determined. The critical ignition energy is estimated, and its variation under real conditions is analyzed. Translated fromFizika Goreniya i Vzryva, Vol. 34, No. 6, pp. 14–22, November–December 1998. The paper is reported at the 2nd International Conference on Forest Fires (Irkutsk, 10–15 June, 1997).  相似文献   
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