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1.
Mosquito-borne Zika virus (ZIKV) became a real threat to human health due to the lack of vaccine and effective antiviral treatment. The virus has recently been responsible for a global outbreak leading to millions of infected cases. ZIKV complications were highlighted in adults with Guillain–Barré syndrome and in newborns with increasing numbers of congenital disorders ranging from mild developmental delays to fatal conditions. The ability of ZIKV to establish a long-term infection in diverse organs including the kidneys has been recently documented but the consequences of such a viral infection are still debated. Our study aimed to determine whether the efficiency of ZIKV growth in kidney cells relates to glucose concentration. Human kidney HK-2 cells were infected with different ZIKV strains in presence of normal and high glucose concentrations. Virological assays showed a decrease in viral replication without modifying entry steps (viral binding, internalization, fusion) under high glucose conditions. This decrease replication was associated with a lower virus progeny and increased cell viability when compared to ZIKV-infected HK-2 cells in normal glucose concentration. In conclusion, we showed for the first time that an elevated glucose level influences ZIKV replication level with an effect on kidney cell survival.  相似文献   
2.
Poor aqueous solubility is one of the recurrent drawbacks of many compounds in medicinal chemistry. To overcome this limitation, the dilution of drug candidates from stock solutions of an organic solvent is common practice. However, the precise characterisation of these compounds in aqueous solutions is often neglected, leading to some uncertainties regarding the nature of the actual active species. In this communication, we demonstrate that two ruthenium complexes previously reported by our group for their chemotherapeutic potential against cancer, namely [Ru(DIP)2(sq)](PF6) and [Ru(DIP)2(3-methoxysq)](PF6), where DIP is 4,7-diphenyl-1,10-phenanthroline, sq=semiquinonate and 3-methoxysq=3-methoxysemiquinonate, form colloids in water-DMSO (1 % v/v) mixtures that are invisible to the naked eyes. [Ru(DIP)2(3-methoxysq)](PF6) was found to form a highly stable and monodispersed colloid with nanoaggregates of ∼25 nm. In contrast, [Ru(DIP)2(sq)](PF6) was found to form large reticulates of mostly spherical aggregates which size was found to increase over time. The difference in size and shape distribution of drug candidates is of tremendous significance as the study of their biological activity might be severely affected. Overall, we strongly believe that these observations should be taken into account by the scientific community working on the development of metal-based drugs with poor water solubility.  相似文献   
3.
An addition of boron largely increases the ductility in polycrystalline high-temperature Co–Re alloys. Therefore, the effect of boron on the alloy structural characteristics is of high importance for the stability of the matrix at operational temperatures. Volume fractions of ε (hexagonal close-packed—hcp), γ (face-centered cubic—fcc) and σ (Cr2Re3 type) phases were measured at ambient and high temperatures (up to 1500 °C) for a boron-containing Co–17Re–23Cr alloy using neutron diffraction. The matrix phase undergoes an allotropic transformation from ε to γ structure at high temperatures, similar to pure cobalt and to the previously investigated, more complex Co–17Re–23Cr–1.2Ta–2.6C alloy. It was determined in this study that the transformation temperature depends on the boron content (0–1000 wt. ppm). Nevertheless, the transformation temperature did not change monotonically with the increase in the boron content but reached a minimum at approximately 200 ppm of boron. A probable reason is the interplay between the amount of boron in the matrix and the amount of σ phase, which binds hcp-stabilizing elements (Cr and Re). Moreover, borides were identified in alloys with high boron content.  相似文献   
4.
The objective of this research was to investigate the feasibility of visible transmission spectroscopy for the non‐destructive assessment of the freshness of an individual egg. A total of 600 intact white‐shelled eggs of the same flock (Lohmann, 40 weeks of age) were measured. To obtain a considerable variation in freshness, groups consisting of 60 eggs were stored (18 °C, 55% RH) for 0, 2, 4, 6, 8, 10, 12, 14, 16 and 18 days. The non‐destructive spectral measurements were compared with the two most widely used destructive freshness parameters, namely Haugh units and albumen pH. A partial least squares (PLS1) model was built in order to predict Haugh units and pH of the albumen based on the transmission spectra. The correlation coefficients between the predicted value and the measured value were 0.842 and 0.867 for Haugh unit and pH of the albumen, respectively. These results show that the light transmission spectrum of an egg provides quantitative information about egg freshness. Relevant information concerning egg freshness is restricted to the interval between 570 and 750 nm. Furthermore, the models obtained for both destructive parameters were strikingly similar, indicating that Haugh unit and pH have the same physico‐chemical background. Copyright © 2006 Society of Chemical Industry  相似文献   
5.
6.
The extinction coefficient ? at 2.9 μm for OH in fluoride glasses is measured by determining the amount of HF evolved during heating of the glass under steam and the corresponding intensity of the OH absorption band. This coefficient is respectively equal to 31 litre mole?1 cm?1 for BTYbZ glass (15 BaF2 - 29 ThF4 - 28 YbF3 - 28 ZnF2) and 19.5 litre mole?1 cm?1 for BALLA glass (34 BaF2 - 57 ZrF4 - 4 AlF3 - 5 LaF3).  相似文献   
7.
JaTS, a Java 2D seismic tomography software, is presented. It implements original algorithms achieving optimal accuracy with reasonable computing costs. A second-order Fast Marching Method (FMM) is used for solving the eikonal equation, therefore enabling a fast and robust computation of seismic traveltimes between sources and receivers. The wavepaths are materialized by Fresnel volumes rather than by conventional rays. This approach accounts for complex velocity models and has the advantage of considering the effects of the wave frequency in the velocity model resolution. The model is computed by a Simultaneous Iterative Reconstruction Technique (SIRT) which has been reformulated to integrate Fresnel wavepaths by using a probabilistic approach. In addition, various utilities are implemented, such as a tapering filter, used to decrease artifact effects occurring in the vicinity of the sources and receivers. The software also offers the possibility of reconstructing the velocity field on a grid larger than the one used for the wave propagation computation. This contributes to stabilize the estimated values. All of the seismic processing tools have been integrated with a user-friendly graphical interface. JaTS represents a tightly integrated tool suite that supports the entire process of importing the SG2 field records, first-break picking, forward modeling and velocity-field computing across multiple platforms.  相似文献   
8.
High cycle fatigue of bolted connections Extensive tests regarding the influences on the fatigue of bolt‐nut‐connections of preloading with torsion, of preloading with yielding, of loading with superimposed bending and of the tested lot are processed. These influences are not yet known according to VDI 2230. New testing devices were designed for these tests, which allow a far less expensive operation and may easily be used for bolts of diameters up to M100 and testing frequencies up to 1000 Hz. The validity of fatigue resistance according to VDI 2230 is specified with respect to the test results. The determined influence of the tested lots is unexpectedly high. The manufacturing process of bolts should be improved to minimize this influence.  相似文献   
9.
Organizations often fulfil their storage needs by supplementing their own warehouse with leased space, a scenario modeled here under the assumption of constant product demand. Closed-form formulae are obtained for the decision variables of interest, namely, the replenishment lot size and the warehouse size, as well as the amount of space to lease. Cost savings due to leasing are shown to have an upper bound of approximately 29% when the optimal warehouse capacity can be installed without restrictions (such as a budgetary constraint). A numerical example further indicates that leasing is significantly more beneficial when the warehouse size is tightly constrained, and that total costs are robust with respect to demand fluctuations.  相似文献   
10.
Previous studies have shown that bizarre and common images produce equivalent levels of recall in unmixed-list designs. Using unmixed lists, we tested the view that bizarre images would be less susceptible than common images to common sources of interference. In all experiments, subjects imaged a list of either bizarre or common sentences and then performed some kind of interfering task before recalling the initial list of sentences. Experiment 1 showed that bizarre images were better accessed than common images after imaging an intervening list of common sentences. Also, components of common images tended to be better recalled than those of bizarre images after imaging an intervening list of bizarre sentences. Experiments 2a and 2b showed that interfering tasks consisting of studying lists of common concrete nouns did not differentially affect memory for bizarre and common images. In Experiment 3, labeling and imaging an interfering list of common pictures produced higher recall of bizarre images. Generally, bizarre images appeared to be less susceptible than common images to interference from certain types of common encodings. Importantly, the superior recall of bizarre images was always due to greater image (sentence) access, whereas higher recall of common images was associated with greater recovery of the image (sentence) constituents. Explanation of the precise pattern of results requires consideration of the distinctive properties of bizarre images. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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