随着无线电技术的进步发展,无线通信系统对宽带平面天线的要求越来越高。平面倒 f 天线(Planar Inverted f Antenna,PIfA)由地板、短路贴片、馈线和接地线构成,具有结构紧凑、剖面低、重量轻、容易制造、易与微波电路集成等诸多优点,能...
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随着无线电技术的进步发展,无线通信系统对宽带平面天线的要求越来越高。平面倒 f 天线(Planar Inverted f Antenna,
PIfA)由地板、短路贴片、馈线和接地线构成,具有结构紧凑、剖面低、重量轻、容易制造、易与微波电路集成等诸多优点,
能够很好的满足无线通信系统系统的需求,因而得到广泛的应用。
The essential oils offruit offoeniculum vulgare subsp. piperitum (Apiaceae) growing wild in South Anatolia were extracted by hydrodistillation, and analysed by GC and GC-MS. The percentage yields of the essential oi...
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The essential oils offruit offoeniculum vulgare subsp. piperitum (Apiaceae) growing wild in South Anatolia were extracted by hydrodistillation, and analysed by GC and GC-MS. The percentage yields of the essential oils from fruits of bitter fennel harvested in different heights were 2.66 %, 2.0 % and 1.66 %, respectively. The major constituents varied depending on harvest years. The major constituents of bitter fennel fruit were methyl chavicol (estragol), fenchone and limonene. Methyl chavicol contents of oil changed between 50.2 % (600 m height) to 69.2 % (1600 m height). fenchone contents of samples varied between 6.5 % and 32.8 %. The highest fenchone content was established at the level of 600 m height. While limonene contents of oil were found as 7.1 % and 8.2 % for 600 m and 1600 m heights, respectively, it was determined as 0.37 % for sea level.
This work provides some feasible regions for the existence of traversable wormhole geometries in modified f ( 𝒢 , T ) gravity. for this purpose, three different matter contents have been studied with special e...
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This work provides some feasible regions for the existence of traversable wormhole geometries in modified f ( 𝒢 , T ) gravity. for this purpose, three different matter contents have been studied with special emphasis on anisotropic fluid by considering a specific f ( 𝒢 , T ) gravity power law model. It has been shown that the null energy conditions for the effective energy–momentum tensor are widely violated for the ordinary matter content. However, some small feasible regions to support the wormhole solutions have been noted. furthermore, the stability of the anisotropic feasible regions for the wormhole solutions has been discussed. It is concluded that the wormhole geometries threaded by the ordinary matter actually exist and are well stable in f ( 𝒢 , T ) gravity.
Conjugative plasmids encode genes that enable them to transfer, by conjugation, from a given host cell to another cell. Conjugative transfer, despite being an important feature of conjugative plasmids, is not constitu...
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Conjugative plasmids encode genes that enable them to transfer, by conjugation, from a given host cell to another cell. Conjugative transfer, despite being an important feature of conjugative plasmids, is not constitutive for most plasmids, the reason being that genes involved in horizontal transfer are mostly repressed. Only upon their transient de-repression are plasmids able to transfer horizontally. If host cells harbour multiple plasmids, their simultaneous transfer depends on simultaneous transient de-repression of all plasmids. If de-repression of different plasmids was random and independent events, simultaneous de-repression should be a rare event because the probability of simultaneous de-repression would be the product of the probabilities of de-repression of each plasmid. Some previous observations support this hypothesis, while others show that co-transfer of plasmids is more frequent than this reasoning indicates. Here, we show that co-transfer of multiple plasmids mainly results from non-independent events: the probability that all plasmids within a cell become de-repressed is much higher than if de-repression of plasmids genes were independent. We found a simple model for the probability of co-transfer: the plasmid having the lowest conjugation rates is the one who limits co-transfer. In this sense, cells receiving the plasmid with the lower transfer rate also receive the other plasmid. If de-repression happens simultaneously onco-resident plasmids, common cues may stimulate de-repression of distinct plasmids.
This essay employs insights from embodied approaches to cognition to develop a tighter grasp on the phenomenon of camera mobility. Close readings of two early masterpieces of German cinema investigate how the viewer r...
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This essay employs insights from embodied approaches to cognition to develop a tighter grasp on the phenomenon of camera mobility. Close readings of two early masterpieces of German cinema investigate how the viewer relates to camera movement on the basis of kinaesthetic empathy and is thereby transported, emotionally gripped or expelled from the storyworld. I argue that the construction of the fictional world is based on this specific viewing attitude, which invites us either to merely observe or, in contrast, to engage with the events on screen. As a consequence, the investigation of camera movement on the basis of embodied cognition helps us both to gain a deeper understanding of how we are drawn into the space defined by camera movement and to open up the possibility of a natural' history of camera conventions as they were established at this early stage of cinema.
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