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A. R. P. Bertocco I. P. Migacz V. L. P. Santos C. R. C. Franco R. Z. Silva R. A. Yunes V. Cechinel‐Filho J. M. Budel 《Microscopy research and technique》2017,80(8):831-837
Piper solmsianum C.DC., which is popularly known as pariparoba, is a shrub that measures 1–3 m in height and it inhabits areas with wet tropical soils. The objective of this study was to analyze the leaf and stem anatomy using light microscopy, scanning electron micrographs, and energy‐dispersive X‐ray spectroscopy in order to provide information for species identification. The anatomical profile showed the following main microscopic markers: hypostomatic leaf; hypodermis layer on both sides; pearl glands; biconvex midrib shape; five collateral vascular bundles in open arc with the central bundle larger than the others; circular stem shape; collateral vascular bundles arranged in two rings; sinuous sclerenchymatic sheath in the pith; secretory idioblasts; and starch grains in the mesophyll, in the ground parenchyma of the midrib, petiole, and in the stem; and six morphotypes of calcium oxalate crystals (styloids, cuneiform, tabular crystal rosettes, cuneiform crystal rosettes, elongated square dipyramids, as well as very elongated square dipyramids). 相似文献
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Jorge Laine Joaquin Brito Francisco Severino Germán Castro Patricia Tacconi Simón Yunes José Cruz 《Catalysis Letters》1990,5(1):45-54
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst. 相似文献
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Yunes Shafaat GharamalekiMehrzad Shams 《Vacuum》2011,86(3):311-317
In high vacuum systems or materials that have fine capillaries, the molecular transport can be characterized as being free-molecular flow regime. In this flow regime intermolecular interactions can be ignored and flow is determined entirely by molecule-surface collisions. The transport of gases and volatile compounds through porous media and filters with variety of geometries is of great interest in various industrial applications. Although the effect of porosity on gas flow in the most of the flow regimes has been explored, but there are a few investigations on gas transport in porous media and filers at free-molecular regime. In this investigation gas transport in porous media with various porosities and geometries is explored. Test Particle Monte-Carlo (TPMC) method is employed. The walls are assumed to be diffusive. The skeletal portion of the porous media (frame) is modelled by solid spheres. The developed numerical scheme is validated with non porous cases. The effect of porosity, sphere sizes of frame, porous geometry, gas type and temperature on the conductance is examined. The simulations are performed for a porous pipe and porous nozzle. Results demonstrate that porosity and filtration highly affects the conductance of pipe and nozzle and causes great pressure drop in high vacuum systems. The increase of sphere sizes at constant porosity causes conductance to grow. The gas type and temperature of gas affects the conductance of pipe and nozzle too. 相似文献
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V Cechinel Filho AR Santos RO De Campos OG Miguel RA Yunes F Ferrari I Messana JB Calixto 《Canadian Metallurgical Quarterly》1996,48(12):1231-1236
We studied retrospectively the effect of long-term treatment with an inhaled corticosteroid on bronchial hyperresponsiveness (BHR) and clinical asthma in moderate-severe asthmatic subjects. Fifty-eight patients who had used beclomethasone dipropionate (BDP) over one year, were enrolled in this study. BHR was measured before and after treatment with BDP by the methods recommended by Japanese Society of Allergology. Moreover we examined the clinical factors and the frequency of acute exacerbations. The results as follows: 1) The mean age was 48.8 years and the mean asthma history was 9.2 years. The mean dose and mean time of BDP administration was 801 micrograms/day and 28.1 months, respectively. 2) Patients during BDP treatment over one year showed about 6-fold mean improvements in BHR, but there were many patients who showed no improvements in BHR. 3) We retrospectively divided all the patients into two groups. Namely, the improved group (n = 25) showed more than 4 fold improvement in BHR and unchanged group (n = 33), less than 4-fold. But there were no significant differences in clinical characteristics and %FEV1 during treatment with BDP. 4) The unchanged group had more near fatal episodes in the past than the improved group. 5) There was significant decrease in acute exacerbation during treatment with BDP, but the unchanged group had more acute exacerbations than the improved group during treatment with BDP. These results indicates that there are many patients who had no improvement on BHR with long term BDP treatment and they have more acute exacerbations due to various stimuli. In conclusion, asthma is recognized chronic inflammatory disease and inhaled corticosteroid therapy has been recommended as the first line therapy. We must further study the clinical problems and underlying mechanisms concerning about treatment with an inhaled corticosteroid. 相似文献
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Venera Z. Nezametdinova Roman A. Yunes Marina S. Dukhinova Maria G. Alekseeva Valery N. Danilenko 《International journal of molecular sciences》2021,22(17)
Bifidobacteria are some of the major agents that shaped the immune system of many members of the animal kingdom during their evolution. Over recent years, the question of concrete mechanisms underlying the immunomodulatory properties of bifidobacteria has been addressed in both animal and human studies. A possible candidate for this role has been discovered recently. The PFNA cluster, consisting of five core genes, pkb2, fn3, aaa-atp, duf58, tgm, has been found in all gut-dwelling autochthonous bifidobacterial species of humans. The sensory region of the species-specific serine-threonine protein kinase (PKB2), the transmembrane region of the microbial transglutaminase (TGM), and the type-III fibronectin domain-containing protein (FN3) encoded by the I gene imply that the PFNA cluster might be implicated in the interaction between bacteria and the host immune system. Moreover, the FN3 protein encoded by one of the genes making up the PFNA cluster, contains domains and motifs of cytokine receptors capable of selectively binding TNF-α. The PFNA cluster could play an important role for sensing signals of the immune system. Among the practical implications of this finding is the creation of anti-inflammatory drugs aimed at alleviating cytokine storms, one of the dire consequences resulting from SARS-CoV-2 infection. 相似文献
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The patterns of sexual behavior of the South American cricetid Calomys musculinus, the corn mouse, were observed in 36 pairs of laboratory-reared mice during the postpartum estrus. Copulatory behavior was displayed by 26 of these pairs, 15 of which were observed with their litter in the arena. The other 11 pairs had their litters removed immediately after parturition. The behavioral elements were classified in 21 mutually exclusive categories. Seven categories were noninteractive (the animals performed them by themselves). Agonistic behaviors were predominant in male–female encounters in this species, accounting for 6 of the interactive categories. A kind of fighting, probably a ritualized one, usually precedes copulation. Removal of the litter decreases the incidence of aggression by females and increases the incidence of other interactive behaviors by males (e.g., grooming or sniffing the female, especially the genitals). The incidence of precopulatory fighting is not modified by the presence or absence of the litter, however. The copulatory behavior of this species has a general pattern of no lock, intravaginal thrusting, a single intromission per ejaculation, and multiple ejaculations. Copulation started after a short latency. Most pairs performed only two ejaculatory series. The ejaculation latency was shorter than those of other South American species. When compared with other cricetids displaying intravaginal thrusting, the corn mouse performs a high number of thrusts in the intromission with ejaculation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Nelson L. S. da Fonseca Sergio A. Yunes 《Journal of Network and Systems Management》2004,12(2):147-154
This paper introduces a novel policing mechanism, called Packet Leaky Bucket in which all cells of a frame are marked with the same level of priority. Moreover, it discusses the need for having a frame discard mechanism in cell-switched networks when frame-oriented policing mechanisms are used. 相似文献
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