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排序方式: 共有290条查询结果,搜索用时 15 毫秒
281.
In this article we have undertaken a qualitative and quantitative comparison of common approaches used to develop distributed solutions in Java: RMI and Web services for regular unsecured communication, RMI‐SSL and WS‐Security for secure communication and authentication, and HTTP‐to‐port and HTTP‐to‐CGI/servlet tunnelling for RMI communication through firewalls and proxies. We have performed a functional comparison that helps with the selection of the most appropriate approach. We have also carried out a detailed performance analysis with the identification of major bottlenecks, identification of design and implementation guidelines for distributed applications, and specification of optimizations for distributed middleware. This article contributes to the understanding of different approaches for developing Java distributed applications, provides detailed performance analysis, presents design and implementation guidelines, and identifies the major performance overheads. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
282.
Magnetic resonance spectroscopy (1H MRS) and imaging (MRI) were used to investigate the effects of a bout of moderate prolonged exercise on intra (IMCL)- and
extramyocellular lipid (EMCL) utilization in the soleus, tibialis anterior, and gastrocnemius muscles of five trained human
subjects. MRI and 1H MRS measurements were obtained before and after a 90 min run on a calibrated treadmill at a velocity corresponding to 64±1.5%
of each subjects' maximal rate of oxygen consumption. There were significant decreases in IMCL following exercise in the tibialis
(pre: 22.37±4.33 vs. post: 15.16±3.25 mmol/kg dry wt; P<0.01) and soleus (pre: 36.93±1.45 vs. post: 29.85 ±2.44 mmol/kg dry wt; P<0.01) muscles. There was also a decrease in the gastrocnemius muscle, although this did not reach the level of significance
(pre: 33.78±5.35 vs. post: 28.48±5.44 mmol/kg dry weight; P<0.10). No significant changes were observed in EMCL or subcutaneous fat. In conclusion, this study showed that IMCL were
significantly utilized in the tibialis and soleus muscles of aerobically endurance-trained humans. The absence of significant
utilization of IMCL in the gastrocnemius may reflect differences in fiber type and/or intensity of contraction for each muscle
group. 相似文献
283.
Xiaona Wen Luping Ou Gabriel Cutshaw Saji Uthaman Yu-Chuan Ou Tian Zhu Sarah Szakas Brandon Carney Jacob Houghton Alexander Gundlach-Graham Marjan Rafat Kai Yang Rizia Bardhan 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(29):2204293
The in vivo dynamics of nanoparticles requires a mechanistic understanding of multiple factors. Here, for the first time, the surprising breakdown of functionalized gold nanostars (F-AuNSs) conjugated with antibodies and 64Cu radiolabels in vivo and in artificial lysosomal fluid ex vivo, is shown. The short-term biodistribution of F-AuNSs is driven by the route of systemic delivery (intravenous vs intraperitoneal) and long-term fate is controlled by the tissue type in vivo. In vitro studies including endocytosis pathways, intracellular trafficking, and opsonization, are combined with in vivo studies integrating a milieu of spectroscopy and microcopy techniques that show F-AuNSs dynamics is driven by their physicochemical properties and route of delivery. F-AuNSs break down into sub-20 nm broken nanoparticles as early as 7 days postinjection. Martini coarse-grained simulations are performed to support the in vivo findings. Simulations suggest that shape, size, and charge of the broken nanoparticles, and composition of the lipid membrane depicting various tissues govern the interaction of the nanoparticles with the membrane, and the rate of translocation across the membrane to ultimately enable tissue clearance. The fundamental study addresses critical gaps in the knowledge regarding the fate of nanoparticles in vivo that remain a bottleneck in their clinical translation. 相似文献
284.
285.
Wilkinson Leonora; Beigi Mazda; Lagnado David A.; Jahanshahi Marjan 《Canadian Metallurgical Quarterly》2011,25(3):286
Objective: Evidence from functional imaging and clinical studies on patients with Parkinson's disease (PD) or Huntington's disease (HD) suggests that the basal ganglia play a crucial role in learning on the weather prediction task (WPT). Using deep brain stimulation (DBS) on versus off methodology, the aim of this study was to investigate the effect of altering the output from the basal ganglia to the prefrontal cortex on implicit probabilistic classification learning on the WPT by patients with PD. Method: Eleven PD patients with bilateral DBS of the subthalamic nucleus (STN) and 13 matched controls completed 200 trials of the WPT on 2 separate occasions, with the patients tested with DBS of the STN on or off. Results: DBS of the STN had no effect on overall WPT learning. However, STN DBS selectively improved implicit learning of cue combinations that were weakly (implicitly), rather than strongly (explicitly), associated with the WPT outcome. Conclusions: Results suggest that the STN plays a role in implicit probabilistic classification learning by altering basal ganglia output to the frontal cortex. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
286.
Marjan Heidary Mehdi Khoobi Sabrieh Ghasemi Zohreh Habibi Mohammad Ali Faramarzi 《Advanced Synthesis \u0026amp; Catalysis》2014,356(8):1789-1794
This paper describes the synthesis of quinazolinones via a tandem reaction using the laccase‐mediator system under mild conditions. The procedure involved the laccase‐catalyzed oxidation of alcohols to the corresponding aldehydes, followed by cyclocondensation with isatoic anhydride and a number of amines to afford 2,3‐dihydroquinazolin‐4(1H)‐ones, which were further oxidized to quinazolinones in useful yields. The use of an enzyme as the catalyst, O2 as an environmentally friendly oxidant, and a citrate buffer as the green solvent represents a novel and efficient approach for the one‐pot synthesis of quinazolinones.
287.
Marjan Radi Behnam Dezfouli Kamalrulnizam Abu Bakar Shukor Abd Razak Tan Hwee-Pink 《Wireless Networks》2014,20(7):1807-1823
With respect to the inherent advantages of multipath routing, nowadays multipath routing is known as an efficient mechanism to provide even network resource utilization and efficient data transmission in different networks. In this context, several multipath routing protocols have been developed over the past years. However, due to the time-varying characteristics of low-power wireless communications and broadcast nature of radio channel, performance benefits of traffic distribution over multiple paths in wireless sensor networks are less obvious. Motivated by the drawbacks of the existing multipath routing protocols, this paper presents an Interference-Minimized MultiPath Routing protocol (IM2PR) which aims to discover a sufficient number of minimum interfering paths with high data transmission quality between each event area and sink node in order to provide efficient event data packet forwarding in event-driven wireless sensor networks. Extensive performance evaluations show that IM2PR presents improvements over the Micro Sensor Multipath Routing Protocol and Energy-Efficient data Routing Protocol as follows: 50 and 70 % in term of packet reception ratio at the sink, 44 and 80 % in term of goodput, 33 and 40 % in term of packet delivery latency, 40 and 57 % in term of energy consumption, 50 and 60 % in term of packet delivery overhead. 相似文献
288.
The purpose of this research was to produce a xanthan gum–lysozyme conjugate (Lyz–XM) and to investigate the effect of conjugation on functional properties and antimicrobial properties of the conjugated products. The antimicrobial activity of Lyz is limited to Gram positive bacteria, but its antibacterial spectrum can be extended towards Gram negative bacteria by conjugation with carbohydrate through the Maillard reaction. Lyz was allowed to react with XG under mild Maillard reaction condition (pH 8.5 and 60 °C for 10 days) and conjugation was confirmed by SDS-PAGE, enzyme activity and determination of sugar content of the product. Results showed that under optimal conditions approximately 1.9 mmol XG was attached to one mol Lyz. The Lyz–XG conjugate showed higher solubility at acidic pHs and at different temperatures, increased heat stability with improved emulsion and foaming properties. Additionally, Lyz–XG conjugate showed antioxidant properties and significantly inhibited the growth of Staphylococcus aureus and Escherichia coli in a dose dependent manner. These findings may broaden food applications of Lyz as a functional ingredient with high quality emulsifier, foam producer or natural antibacterial agent in food or pharmaceutical industries. 相似文献
289.
Sweet cherries cv. Lambert Compact were treated with 1-methylcyclopropene (1-MCP) at 0, 180 and 360 nL/L for 2 h at 25 °C and then stored at 2–4 °C in refrigerator. Their quality was measured after 12 days of storage in terms of the contents of total and individual anthocyanins and hydroxycinnamic acids, occurrence of rot, and colour change. Colour change was monitored at three day intervals during storage in the CIE L*, a*, b* colour space. 1-MCP did not retard colour change. The contents of total and individual anthocyanins and hydroxycinnamic acids showed no correlation with the colour behaviour of the cherries. All cherries lost their initial shiny red colour on storage, regardless of the treatment. 1-MCP reduced sweet cherry rot at the highest concentration used (360 nL/L) – only 6% were rotten after 12 days in the refrigerator. This differed significantly (P < 0.05) from untreated fruits and those treated with 180 nL/L 1-MCP which resulted on average in 14 and 20% rot (not statistically different P < 0.05), respectively. The occurrence of rot was shown to be correlated with anthocyanin accumulation, (R = 0.62, P < 0.10). The profile of individual anthocyanins and hydroxycinnamic acids in sweet cherry was not affected neither by cold storage nor 1-MCP treatment. 相似文献
290.
Arjan Gijsenij Marjan Vazirian Peter Spiers Stephen Westland Pim Koeckhoven 《Color research and application》2023,48(1):69-87
Designing a mood board is a creative tool designers often employ at the start of a new (interior) design project. The colors of a mood board represent important information about the envisioned interior designs. In this article, we focus on digital mood boards and we propose a novel method to determine the mood boards' key colors from a design perspective using dE-means color clustering. This proposed algorithm includes a fixed initialization to overcome the non-deterministic nature of traditional k-means, and a merging step to ensure all colors in the calculated palette are at least a dE-threshold apart. Quantitative and qualitative results demonstrate that the proposed algorithm outperforms existing methods in determining the key colors from a design perspective. Additionally, we introduce a novel method to visualize the calculated color palettes that takes into account the contribution of individual pixels to the construction of the calculated color palettes. Finally, we demonstrate how the proposed algorithm can be used to characterize color palettes for various design styles like modern, industrial and art deco. 相似文献