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1.
High vertical wave-number modes clearly dominate the internal wave field during the stratification period in Boadella reservoir in northeast Spain. In this period, the extraction of hypolimnetic water, due to summer irrigation, brought the surface level down by 6 m in one month and the epilimnetic water progressively occupied the whole water column. The temperature profile, with the exception of a few meters at the surface layer, presented an almost constant temperature gradient of about 0.7°C/m. The period of the main vertical mode is 24 h with an amplitude of around 1 m. Thermistor chain records and meteorological data allow us to deduce that this mode is, at least, a third vertical mode forced by the wind, which normally has a typical periodicity of 24 h. However, when the wind changes direction from south to north, the circulation cells developed due to this forced nonstationary oscillation are destroyed. When this occurs, the Bulk Richardson number is Rib ~ 1. Similar vertical structures as a response to wind forcing should be expected in similar systems, although this has not been reported in the literature.  相似文献   
2.
Four experiments contrasted the cue-familiarity hypothesis of feeling-of-knowing judgments (FKJs) and tip-of-the-tongue feelings (TOTs) to the target-retrievability hypothesis. Familiarity of the cues was contrasted to memorability of the targets in a paired-associate design (e.g., A-B A-B, A-B A-B', A-B A-D, A-B C-D), in which the number of repetitions of the cue A terms was dissociated from the memorability of the target B terms. Little support was found for the target-retrievability hypothesis, because in none of the 4 experiments were FKJs related to target memorability. In one experiment, an omnibus retrieval hypothesis (which implicates total retrieval rather than just correct retrieval) and the cue-familiarity hypothesis produced isomorphic predictions that were borne out by the FKJ and TOT results. All 4 experiments supported the cue-familiarity hypothesis, because FKJs and TOTs were directly related to the number of presentations (and thereby the familiarity) of the cues.  相似文献   
3.
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry  相似文献   
4.
This paper provides evidence about institutional investors' attitudes and perceptions of residential property as an investment asset group in three European countries (Switzerland, the Netherlands and Sweden). These countries stand out, with an extraordinarily large institutional residential ownership, in fact, residential institutional allocation represents about 6 per cent, 2 per cent and 3 per cent of the total institutional investment in Switzerland, the Netherlands and Sweden, respectively. Housing is the most important institutional property asset type in Switzerland and the Netherlands, comprising over 52 per cent and 50 per cent of their institutional property portfolios, respectively. In Sweden residential property plays an important, but not dominant role in the domestic institutional property portfolios, representing about 21 per cent of the institutional property holdings. Using a postal survey of representatives of pension funds, insurance companies, property investment and asset management companies the study analyses the attractiveness of residential property in terms of institutional investment goals. The survey examines the institutional investors' perceptions of housing investment, namely with respect to its returns, volatility, inflation hedging, liabilities matching and correlation with shares, bonds and non-residential property. Additionally, the survey looks at the institutional investors' experiences regarding the private rented sector. The survey suggests that investment in residential property equity is likely to be done through larger portfolios, which tend to invest in housing directly. Residential property is seen mainly as an earning asset group able to provide diversification benefits for investors even when portfolios already include non-residential property. The respondents are mainly concerned with rent regulation issues, the lack of well-structured investment vehicles is undoubtedly a less important problem.  相似文献   
5.
We present a method for measuring the electrical conductivity of metallic materials that relies on the ratio of two loaded Q factors, QR/QX, with QR corresponding to a TE011-mode reference cavity made of aluminum, and QX the Q that results upon replacing the aluminum plate with the one fabricated from the material to be examined. Electrical conductivity is mathematically inferred from the ratio QR/QX where the loaded Q factors are measured by using the transmission-type method. Within a 3.0 percent accuracy, conductivities determined at 8.7 GHz for electrolytic copper (5.6 times 107 S/m) and brass (1.6 times 107 S/m) show to be in good agreement with those reported in the literature.  相似文献   
6.
Recombinant cytochrome b5 was extracted into the reversed micelle phase of an anionic surfactant (AOT) in octane and back-extracted to a final aqueous phase. The extraction of the protein was controlled by an electrostatic mechanism, since it was dependent on the global charge of the protein. This was directly demonstrated by experiments with native and mutant cytochromes obtained by site directed mutagenesis. The back-extraction of cytochrome b5 to a fresh aqueous phase was decreased by factors that reduced the size of the water pool of the organic phase, such as high salt concentrations (1–2 mol dm?3 NaCl) and low temperatures (4°C), probably because of an increase in a favourable interaction of this protein with the surfactant at closer distances.  相似文献   
7.
In finite labelled transition systems the problems of deciding strong bisimilarity, observation equivalence and observation congruence areP-complete under many—oneNC-reducibility. As a consequence, algorithms for automated analysis of finite state systems based on bisimulation seem to be inherently sequential in the following sense: the design of anNC algorithm to solve any of these problems will require an algorithmic breakthrough, which is exceedingly hard to achieve.  相似文献   
8.
We currently lack effective treatments for the devastating loss of neural function associated with spinal cord injury (SCI). In this study, we evaluated a combination therapy comprising human neural stem cells derived from induced pluripotent stem cells (iPSC-NSC), human mesenchymal stem cells (MSC), and a pH-responsive polyacetal–curcumin nanoconjugate (PA-C) that allows the sustained release of curcumin. In vitro analysis demonstrated that PA-C treatment protected iPSC-NSC from oxidative damage in vitro, while MSC co-culture prevented lipopolysaccharide-induced activation of nuclear factor-κB (NF-κB) in iPSC-NSC. Then, we evaluated the combination of PA-C delivery into the intrathecal space in a rat model of contusive SCI with stem cell transplantation. While we failed to observe significant improvements in locomotor function (BBB scale) in treated animals, histological analysis revealed that PA-C-treated or PA-C and iPSC-NSC + MSC-treated animals displayed significantly smaller scars, while PA-C and iPSC-NSC + MSC treatment induced the preservation of β-III Tubulin-positive axons. iPSC-NSC + MSC transplantation fostered the preservation of motoneurons and myelinated tracts, while PA-C treatment polarized microglia into an anti-inflammatory phenotype. Overall, the combination of stem cell transplantation and PA-C treatment confers higher neuroprotective effects compared to individual treatments.  相似文献   
9.
We analyze the complexity of equilibria problems for a class of strategic zero-sum games, called angel-daemon games. Those games were introduced to asses the performance of the execution of a web orchestration on a moderate faulty or under stress environment. Angel-daemon games are a natural example of zero-sum games whose representation is naturally succinct. We show that the problems of deciding the existence of a pure Nash equilibrium or of a dominant strategy for a given player are ${\Sigma}^{p}_{2}$ -complete. Furthermore, computing the value of an angel-daemon game is EXP-complete. Thus, our results match the already known classification of the corresponding problems for the generic families of succinctly represented games with exponential number of actions.  相似文献   
10.
Traditional cloud computing providers enable developers to program and deploy applications in the cloud by using platform as a service (PaaS) providers. Despite the benefits of such an approach, this service model usually comes with a high level of the lock in effect into the service provider. The lock in effect occurs when a software developer needs to change its cloud provider. When this happens, it usually means a major application rewrite, specific for the new PaaS. This paper details the initial results of a project whose goal is to build a PaaS where vendor lock in does not occur. With this PaaS, developers wishing to deploy their applications into the cloud may continue to program using their usual development environments. There are no necessary changes required to make the application PaaS compatible. As a proof of concept, we developed an open source PaaS management application as a regular web application and then deployed it on the cloud.  相似文献   
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