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81.
Many routing protocols are proposed in the literature on mobile ad hoc networks (MANETs). Some of those protocols which have been investigated under different assumptions are unable to capture the actual characteristics of MANETs. Therefore, there is a necessity to investigate the performance of MANETs under a number of different protocols with various mobility models. This paper evaluates the performance of the single path routing protocols (AODV, DSR, and DSDV), in the presence of different network loads and differing mobility models. Our findings show that DSR routing protocol has a better performance compared to other protocols with respect to various metrics. 相似文献
82.
Brólio MP Vidane AS Zomer HD Wenceslau CV Ozório JJ Martins DS Miglino MA Ambrósio CE 《Microscopy research and technique》2012,75(6):766-770
The umbilical cord blood (UCB) is an important source of hematopoietic stem cells with great deal of interest in regenerative medicine. The UCB cells have been extensively studied as an alternative to the bone marrow transplants. The challenge is to define specific methods to purify and characterize these cells in different animal species. This study is aimed at morphological characterization of progenitor cells derived from UCB highlighting relevant differences with peripheral blood of adult in dog and cats. Therefore, blood was collected from 18 dogs and 5 cats' umbilical cords from fetus in various developmental stages. The mononuclear cells were separated using the gradient of density Histopaque-1077. Characterization of CD34+ cells was performed by flow cytometric analysis and transmission electron microscopy. Granulocytes (ancestry of the basophiles, eosinophiles, and neutrophiles) and agranulocytes (represented by immature lymphocytes) were identified. We showed for the first time the ultrastructural features of cat UCB cells. 相似文献
83.
Dillig Isil Dillig Thomas Li Boyang McMillan Ken Sagiv Mooly 《International Journal on Software Tools for Technology Transfer (STTT)》2017,19(5):535-547
International Journal on Software Tools for Technology Transfer - This paper presents a new technique for synthesizing circular compositional proofs of program correctness. Our technique uses... 相似文献
84.
A corpus of nearly 150,000 maternal word-tokens used by 53 low-income mothers in 263 mother–child conversations in 5 settings (e.g., play, mealtime, and book readings) was studied. Ninety-nine percent of maternal lexical input consisted of the 3,000 most frequent words. Children's vocabulary performance in kindergarten and later in 2nd grade related more to the occurrence of sophisticated lexical items than to quantity of lexical input overall. Density of sophisticated words heard and the density with which such words were embedded in helpful or instructive interactions, at age 5 at home, independently predicted over a third of the variance in children's vocabulary performance in both kindergarten and 2nd grade. These two variables, with controls for maternal education, child nonverbal IQ, and amount of child's talk produced during the interactive settings, at age 5, predicted 50% of the variance in children's 2nd-grade vocabulary. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
MD Ricciardone T Oz?elik B Cevher H Ozda? M Tuncer A Gürgey O Uzunalimo?lu H Cetinkaya A Tanyeli E Erken M Oztürk 《Canadian Metallurgical Quarterly》1999,59(2):290-293
Heterozygous germ-line mutations in the DNA mismatch repair genes lead to hereditary nonpolyposis colorectal cancer. The disease susceptibility of individuals who constitutionally lack both wild-type alleles is unknown. We have identified three offspring in a hereditary nonpolyposis colorectal cancer family who developed hematological malignancy at a very early age, and at least two of them displayed signs of neurofibromatosis type 1 (NF1). DNA sequence analysis and allele-specific amplification in two siblings revealed a homozygous MLH1 mutation (C676T-->Arg226Stop). Thus, a homozygous germ-line MLH1 mutation and consequent mismatch repair deficiency results in a mutator phenotype characterized by leukemia and/or lymphoma associated with neurofibromatosis type 1. 相似文献
86.
F Deymeer P Serdaro?lu M Poda Y Gül?en-Parman T Oz?elik C Ozdemir 《Canadian Metallurgical Quarterly》1997,7(8):521-528
Systemic and topical administration of non-steroidal anti-inflammatory drugs (NSAIDs) has been shown to reduce periodontal disease progression in both animal models and human subjects. Our present research focuses on single enantiomers of these agents to examine whether enantiospecific therapy will be efficacious in slowing periodontitis. The purpose of this study was to evaluate the inhibitory effects of (S)-ketoprofen on experimentally induced alveolar bone loss in beagle dogs. 16, 18-month-old, female beagles were brought to optimal periodontal health over a 2-week pretreatment period. Experimental periodontitis was then induced by placing silk ligatures around premolar and molar teeth and by instituting a soft, plaque-promoting diet. At baseline, animals were randomized to 1 of 4 groups, consisting of 2x daily administration of (1) placebo dentifrice, (2) 0.3% (S)-ketoprofen dentifrice, (3) 3.0% (S)-ketoprofen dentifrice, or (4) 10.0 mg (S)-ketoprofen capsules (p.o.) over a 60 day treatment period. Standardized, periapical radiographs exposed at days 1 and 60 were analyzed by computer-assisted digital radiography in order to assess the rate of alveolar bone loss. Secondary outcomes included technetium 99m-tin-diphosphonate (99mTc-Sn-MDP) uptake and the gingival index. At baseline, no differences were observed among the groups for linear bone height or 99mTc-Sn-MDP uptake ratios. From days 1 to 60, cohorts differed significantly in terms of bone loss rates (p < 0.001). In particular, beagles treated with systemic or topical (S)-ketoprofen (0.3% or 3.0% dentifrices) exhibited significantly lower mean rates of bone loss compared to placebo treated beagles (p < 0.05). Group differences in mean radiopharmaceutical uptake ratio changes approached significance (ANOVA, p = 0.07), where animals treated with topical 0.3% (S)-ketoprofen demonstrated a reduction and other groups demonstrated elevations over the 60-day dosing period. Treatment cohorts did differ significantly with respect to changes in mean gingival indices (p < 0.05). Animals treated with 0.3% or 3.0% (S)-ketoprofen dentifrice exhibited significantly reduced elevations in gingival index scores as compared to placebo treated animals. These data provide evidence that enantiospecific therapy with (S)-ketoprofen, topically or systemically delivered, may alter the progression of periodontal disease in the beagle dog model. 相似文献
87.
Sugarcane bagasse ash as a reinforcing filler in thermoplastic elastomers: Structural and mechanical characterizations
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Maiza da Silva Ozório Elton Aparecido Prado dos Reis Silvio Rainho Teixeira Felipe Silva Bellucci Aldo Eloizo Job 《应用聚合物科学杂志》2015,132(7)
The incorporation of residues as reinforcing fillers in polymer composites has emerged as a viable solution, enabling improvements in the mechanical properties of these materials, and has also resulted in a reduction in the cost of the final product. In this work, sugarcane bagasse ash (SBA) was used as a reinforcing filler in comparison with commercial silica (CS) in thermoplastic elastomers prepared from the compatibility of low‐density polyethylene (LDPE) with natural rubber (NR). The composites were obtained by a physical mixture of LDPE and NR with different proportions of CS and SBA using a Haake rotational rheometer. The samples were analyzed by Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and tensile testing. The results show that SBA has similar properties to CS, thus making its use feasible as a reinforcing filler in thermoplastic elastomers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41466. 相似文献
88.
E. Altin D. M. Gokhfeld S. Demirel E. Oz F. Kurt S. Altin M. E. Yakinci 《Journal of Materials Science: Materials in Electronics》2014,25(3):1466-1473
Eu–Ba–Cu–O composition was synthesized by solid state reaction technique. To determine optimum growth temperature, heat treatment was examined on the material at 880–1,100 °C. Microstructural evolution, phase formation and elemental distribution depending on heat treatments were examined by using X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscope analysis. Optimum fabrication conditions were determined as 1,020 °C for 24 h under oxygen atmosphere and detailed characterization of corresponding compound was performed. The magnetization hysteresis loops are expounded to be the product of superconducting Eu-123 grains and magnetic Eu2+ ions. The peak effect on the magnetization curves was described by the extended critical state model. Scaling of the pinning force was found such that the peak position is proportional to the irreversibility field H irr and the maximum pinning force is proportional to H irr 2 . 相似文献
89.
Composites of hydroxyapatite with partially stabilized zirconia with MgO or MgF2 were pressureless sintered between 1000 °C and 1300 °C. The reactions and transformations of phases were verified by X-ray diffraction. For the hydroxyapatite and zirconia composites with MgO, calcium from the hydroxyapatite diffused into the zirconia phase, and the hydroxyapatite decomposed to tri-calcium phosphate at sintering temperatures higher than 1000 °C. Above about 1200 °C, CaZrO3 was formed. Composites containing the MgF2 decomposed slower than the composites with MgO, which was verified by the changes in the lattice volume of the hydroxyapatite left in these composites. Fluorine ions in MgF2 diffused into hydroxyapatite, which resulted in thermal stability at high sintering temperatures. Composites with MgF2 had higher hardness than those with MgO. The lowest porosity was found in a composite initially containing 10 wt% partially stabilized zirconia and 5 wt% MgF2. 相似文献
90.