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781.
This paper presents results of the spectral (absorption and emission) and photophysical study of 6-aminocoumarin (6AC) in various aprotic hydrogen-bond forming solvents. It was established that solvent polarity as well as hydrogen-bonding ability influence solute properties. The hydrogen-bonding interactions between S1-electronic excited solute and solvent molecules were found to facilitate the nonradiative deactivation processes. The energy-gap dependence on radiationless deactivation in aprotic solvents was found to be similar to that in protic solvents.  相似文献   
782.
The study analysed the effect of low‐concentrated acidic electrolysed water (LCAEW) treatment on meat. Microbiological analysis and colour and sensory quality testing during storage were performed on Longissimus thoracis. FT‐IR and FT‐Raman spectroscopy were used to detect eventual changes in the structure of meat after treatment. Meat samples were sprayed for 120 s with LCAEW (0.001%, 0.01% or 0.1% NaCl solution were electrolysed for 0, 5 or 10 min). The highest reduction in total number of micro‐organisms (3.25 log reduction), yeast and moulds (2.68 log reduction) and psychrotrophs (3.10 log reduction) was observed after spraying the meat samples with 0.1% NaCl electrolysed for 10 min. LCAEW caused a decrease in deoxymyoglobin and metmyoglobin concentration in unstored meat samples. The preliminary sensory studies proved that colour changes are not significant for consumers. The IR and Raman spectra indicate that the structure of compounds of meat tissues are not affected by chlorine and chlorine compounds (LCAEW components). LCAEW has no influence on denaturation of meat protein.  相似文献   
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In this study, new composite bisphosphonate delivery systems were obtained from polyurethanes (PUs) and nanocrystalline hydroxyapatite (HA). The biodegradable PUs were first synthesized from poly(ε-caprolactone) diols (PCL diols), poly(ethylene adipate) diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and HA. Moreover, the PCL diols were synthesized by the ring-opening polymerization catalysed by the lipase from Candida antarctica. Next, composite drug delivery systems for clodronate were prepared. The mechanical properties of the obtained biomaterials were determined. The cytotoxicity of the synthesized polymers was tested. The preliminary results show that the obtained composites are perspective biomaterials and they can be potentially applied in the technology of implantation drug delivery systems.  相似文献   
785.
Research in cognitive neuroscience and in brain–computer interfaces (BCI) is frequently concerned with finding evidence that a given brain area processes, or encodes, given stimuli. Experiments based on neuroimaging techniques consist of a stimulation protocol presented to a subject while his or her brain activity is being recorded. The question is then whether there is enough evidence of brain activity related to the stimuli within the recorded data. Finding a link between brain activity and stimuli has recently been proposed as a classification task, called brain decoding. A classifier that can accurately predict which stimuli were presented to the subject provides support for a positive answer to the question. However, it is only the answer for a given data set and the question still remains whether it is a general rule that will apply also to new data. In this paper we try to reliably answer the neuroscientific question about the presence of a significant link between brain activity and stimuli once we have the classification results. The proposed method is based on a Beta-Binomial model for the population of generalization errors of classifiers from multi-subject studies within the Bayesian hypothesis testing framework. We present an application on nine brain decoding investigations from a real functional magnetic resonance imaging (fMRI) experiment about the relation between mental calculation and eye movements.  相似文献   
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The substitution of selenium oxyanions in the hydroxyapatite structure was examined using multinuclear solid-state resonance spectroscopy (ssNMR). The study was supported by powder X-ray diffractometry (PXRD) and wavelength dispersion X-ray fluorescence (WD-XRF). Samples of pure hydroxyapatite (HA300) and selenate (HA300-1.2SeO4) or selenite (HA300-1.2SeO3) substituted hydroxyapatites were synthesized using the standard wet method and heated at 300 °C to remove loosely bonded water. PXRD data showed that all samples are single-phase, nanocrystalline hydroxyapatite. The incorporation of selenite and selenate ions affected the lattice constants. In selenium-containing samples the concentration of Se was very similar and amounted to 9.55% and 9.64%, for HA300-1.2SeO4 and HA300-1.2SeO3, respectively. PXRD and ssNMR data showed that the selenite doping significantly decreases the crystallite size and crystallinity degree. 31P and 1H NMR experiments demonstrated the developed surface hydrated layer in all samples, especially in HA300-1.2SeO3. 1H NMR studies showed the dehydroxylation of HA during the selenium oxyanions substitution and the existence of hydrogen bonding in structural hydroxyl group channels. 1H→77Se cross polarization NMR experiments indicated that selenites and selenates are located in the crystal lattice and on the crystal surface.  相似文献   
790.
Although less pronounced, social, cognitive, and personality characteristics associated with autism spectrum disorders (ASD) may be present in people who do not meet ASD diagnostic criteria, especially in first-degree relatives of individuals with ASD. Research on these characteristics, referred to as broader autism phenotype (BAP), provides valuable data on potential expressions of autism-specific deficits in the context of family relations. This paper offers a review of research on BAP in siblings of individuals with ASD, focusing on reports regarding social, communication, and cognitive deficits, published from 1993 to 2014. The studies are divided into two groups based on participants’ age: papers on preschool and older siblings of individuals with ASD; and publications on infants at risk for ASD. On the basis of this review, suggestions are offered for further research and its significance for our understanding of the genetic determinants of autism.  相似文献   
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