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81.
82.
A new species of willow from Crete, named Salix kaptarae Cambria, C. Brullo & Brullo, is described and illustrated. Morphologically, it shows close relationships with species belonging to the S. apennina group, mainly with respect to the leaf shape, and the hairy ovary, capsule and base of stamina filaments. Considerations on its ecology, leaf micro‐morphology and conservation status are also provided.  相似文献   
83.
Biodesulfurization of refractory organic sulfur compounds in fossil fuels   总被引:3,自引:0,他引:3  
The stringent new regulations to lower sulfur content in fossil fuels require new economic and efficient methods for desulfurization of recalcitrant organic sulfur. Hydrodesulfurization of such compounds is very costly and requires high operating temperature and pressure. Biodesulfurization is a non-invasive approach that can specifically remove sulfur from refractory hydrocarbons under mild conditions and it can be potentially used in industrial desulfurization. Intensive research has been conducted in microbiology and molecular biology of the competent strains to increase their desulfurization activity; however, even the highest activity obtained is still insufficient to fulfill the industrial requirements. To improve the biodesulfurization efficiency, more work is needed in areas such as increasing specific desulfurization activity, hydrocarbon phase tolerance, sulfur removal at higher temperature, and isolating new strains for desulfurizing a broader range of sulfur compounds. This article comprehensively reviews and discusses key issues, advances and challenges for a competitive biodesulfurization process.  相似文献   
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85.

Background

Newborns come into the world wired to socially interact. Is a propensity to socially oriented action already present before birth? Twin pregnancies provide a unique opportunity to investigate the social pre-wiring hypothesis. Although various types of inter-twins contact have been demonstrated starting from the 11th week of gestation, no study has so far investigated the critical question whether intra-pair contact is the result of motor planning rather then the accidental outcome of spatial proximity.

Methodology/Principal Findings

Kinematic profiles of movements in five pairs of twin foetuses were studied by using four-dimensional ultrasonography during two separate recording sessions carried out at the 14th and 18th week of gestation. We demonstrate that by the 14th week of gestation twin foetuses do not only display movements directed towards the uterine wall and self-directed movements, but also movements specifically aimed at the co-twin, the proportion of which increases between the 14th and 18th gestational week. Kinematic analysis revealed that movement duration was longer and deceleration time was prolonged for other-directed movements compared to movements directed towards the uterine wall. Similar kinematic profiles were observed for movements directed towards the co-twin and self-directed movements aimed at the eye-region, i.e. the most delicate region of the body.

Conclusions/Significance

We conclude that performance of movements towards the co-twin is not accidental: already starting from the 14th week of gestation twin foetuses execute movements specifically aimed at the co-twin.  相似文献   
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Dynamics of compensation for the deprivations of segregation and discrimination, and the support of multiculturalism derived from ethnic cohesion explain the consumption of out-of-home highbrow leisure events by minority/ethnic individuals, immigrants, and their descendants as efforts toward their integration and assimilation in metropolitan areas. Using data from the Houston Area Survey, I examine whether there are any significant ethnic disparities in the attendance at museums and live theatres, which represent a relevant dimension of out-of-home highbrow leisure in Houston. I found that the odds of frequently attending museums and live theatres are lower for Anglos compared with non-Anglos, and higher for US-born individuals with at least one foreign parent compared with US-born individuals with US-born parents. These findings reveal that the audiences of museums and live theatres in Houston are already characterized by a noteworthy ethnic diversity.  相似文献   
88.
Biofilms are layers of microbial cells growing on an interface and they can form highly complex structures adapted to a wide variety of environmental conditions. Biofilm streamers have a small immobile base attached to the support and a flexible tail elongated in the flow direction, which can vibrate in fast flows. Herein we report numerical results for the role of the periodical movement of biofilm streamers on the nutrient uptake and in general on the solute mass transfer enhancement due to flow-induced oscillations. We developed what to our knowledge is a novel two-dimensional fluid-structure interaction model coupled to unsteady solute mass transport and solved the model using the finite element method with a moving mesh. Results demonstrate that the oscillatory movement of the biofilm tail significantly increases the substrate uptake. The mass transfer coefficient is the highest in regions close to the streamer tip. The reason for substrate transfer enhancement is the increase in speed of tip movement relative to the surrounding liquid, thereby reducing the thickness of the mass transfer boundary layer. In addition, we show that the relative mass transfer enhancement in unsteady conditions compared with the rigid static structure is larger at higher flow velocities, and this relative increase favors a more flexible structure.  相似文献   
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The optimisation of a tertiary sulfonamide high-throughput screening hit is described. A combination of high-throughput chemistry, pharmacophore analysis and in silico PK profiling resulted in the discovery of potent sulfonamide oxytocin receptor antagonists with oral exposure and good selectivity over vasopressin receptors.  相似文献   
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