Modulating Protein–Protein Interactions with Visible-Light-Responsive Peptide Backbone Photoswitches

Life relies on a myriad of carefully orchestrated processes, in which proteins and their direct interplay ultimately determine cellular function and disease. Modulation of this complex crosstalk has recently attracted attention, even as a novel therapeutic strategy. Herein, we describe the synthesis and characterization of two visible-light-responsive peptide backbone photoswitches based on azobenzene derivatives, to exert optical control over protein–protein interactions (PPI). The novel peptidomimetics undergo fast and reversible isomerization with low photochemical fatigue under alternatively blue-/green-light irradiation cycles. Both bind in the nanomolar range to the protein of interest. Importantly, the best peptidomimetic displays a clear difference between isomers in its protein-binding capacity and, in turn, in its potential to inhibit enzymatic activity through PPI disruption. In addition, crystal structure determination, docking and molecular dynamics calculations allow a molecular interpretation and open up new avenues in the design and synthesis of future photoswitchable PPI modulators.     

Microcapsules application in graphic arts industry: a review on the state-of-the-art

The process of oil-containing microcapsules production by complex coacervation of gelatine and gum arabic was patented in 1957. Microencapsulation technology gained importance in production of carbonless copy paper as one of the most important commercial products. Development of this technology in later years led to the emergence of different types of microcapsules and the production procedures for various application fields. Nowadays, they are mainly used in medicine, pharmacy, agriculture, construction industry, chemical industry, food industry, biotechnology, cosmetic industry, photography, electronics, textiles and printing industry. This review paper highlights the major types of microcapsules and their applications in production techniques in graphic arts and printing industry, various processing parameters that affect their important characteristics and methods for microcapsules characterization. This paper discusses the applications of microcapsules within printing industry, and feasible printing technologies related to the desired substrate materials. The analysis of these subjects offers a deeper insight into the mechanisms of microcapsule transfer processes, their behavior, and working conditions leading to the final products. It reveals the advantages and the drawbacks of certain printing technologies for microcapsules transfer, which enables the determination of favorable transfer procedure for specific microcapsule type and substrate materials. This paper also provides valuable recommendations and potential solutions on how to overcome the obstacles created by certain printing technologies.     

On the tungsten carbide synthesis for PEM fuel cell application – Problems,challenges and advantages

Fuel cell application of tungsten carbide is revisited starting with four different tungsten carbide precursors used for high temperature synthesis. It was shown that the final products greatly depend on the nature of the precursor. Using tungsten peroxide/2-propanol derived precursor almost pure WC was obtained which was subjected to further electrochemical investigation. It was shown that it is necessary to decorate WC with Pt nanoparticles in order to obtain satisfactory fuel cell performance, but catalytic activity of Pt/WC anode catalyst is not expected to overcome the activity of Pt/C. It is argued that new synthetic routes for the preparation of WC should be directed towards obtaining highly dispersed WC, that is, WC with high external surface area available for Pt deposition, rather than high specific surface area WC with large contribution of micropores having no importance when it comes to the use of WC as a catalyst support. The true benefit of the use of WC as catalyst support is found in increased CO tolerance/CO oxidation activity of WC-supported Pt catalysts. Qualitative mechanistic view on increased CO oxidation activity of Pt/WC is offered.     

An application of learning machine methods in prediction of wear rate of wear resistant casting parts

In this paper, a method of floating ball wear rate identification, using two machine-learning techniques Support Vector Machine (SVM) and Improved Support Vector Machine (ISVM) are proposed. Both models are used to relate the wear rate and technological parameters of the wear resistant drip moulding using different kernel functions. The models for determining the wear rate of white iron casting with low chromium content (flotation balls), was trained and tested by using the existing exploitation data from the Bor Flotation Plant, Serbia. In order to select the best model parameters the statistical indicators for both models are presented. Results show that the ERBF (SVM) and ERBF+POLY (ISVM) achieved the best classification accuracy compare to other kernels used: the absolute mean error of ERB (SVM) is 5.85%, while the error of ERBF+POLY (ISVM) is 6.67%. The tuned ISVM model with mixture of kernels is able to accurately predict the wear rate and can be used to define the optimum chromium content in liquid metal alloys for the casting of flotation balls.     

General Anesthesia and the Young Brain: The Importance of Novel Strategies with Alternate Mechanisms of Action

Over the past three decades, we have been grappling with rapidly accumulating evidence that general anesthetics (GAs) may not be as innocuous for the young brain as we previously believed. The growing realization comes from hundreds of animal studies in numerous species, from nematodes to higher mammals. These studies argue that early exposure to commonly used GAs causes widespread apoptotic neurodegeneration in brain regions critical to cognition and socio-emotional development, kills a substantial number of neurons in the young brain, and, importantly, results in lasting disturbances in neuronal synaptic communication within the remaining neuronal networks. Notably, these outcomes are often associated with long-term impairments in multiple cognitive-affective domains. Not only do preclinical studies clearly demonstrate GA-induced neurotoxicity when the exposures occur in early life, but there is a growing body of clinical literature reporting similar cognitive-affective abnormalities in young children who require GAs. The need to consider alternative GAs led us to focus on synthetic neuroactive steroid analogues that have emerged as effective hypnotics, and analgesics that are apparently devoid of neurotoxic effects and long-term cognitive impairments. This would suggest that certain steroid analogues with different cellular targets and mechanisms of action may be safe alternatives to currently used GAs. Herein we summarize our current knowledge of neuroactive steroids as promising novel GAs.     

Comparative study of different methods for the assessment of print nonuniformity and their correlation with the human visual system

Print nonuniformity is the variation of optical density (reflection) on the print and can occur in several different types that can be classified into two basic groups: random and systematic variations. This article examines two types from each group of variations that are most commonly found in digital printing systems: blotches and streaks, where amplitude and size were varied. Three most commonly used methods for measuring the print nonuniformity were used: Grey Level Co-occurrence Matrix (GLCM), ISO 13660 and Integration (also Improved Integration) method. The results obtained by measuring were compared with a visual assessment to find the link between objective and subjective analysis and to define and determine which method/parameter is the best for the measurement of which type of print (non)uniformity. The obtained results indicate the possibility of selecting the measurement parameter, but that the choice of the parameter depends on the type of nonuniformity. It is concluded that in the case of the GLCM method, the entropy and energy parameters are strongly related to the visual assessment for all three sets of samples. These parameters can be used regardless of the type of nonuniformity. The ISO G parameter can be used to measure both graininess and mottling, while the ISO M parameter is only suitable for measuring mottling. Integration method could be used to measure systematic error. On the basis of conclusions of the research, it is possible to propose the development of an industrially applicable solution for measuring print nonuniformity of digitally printed samples.     

Extractability of antioxidants from legume seed flour after cooking and in vitro gastrointestinal digestion in comparison with methanolic extraction of the unprocessed flour

Antioxidant activities were studied in methanolic and water extracts of nonprocessed, cooked and in vitro enzymatically digested seed flour, as well as in total protein hydrolysates and small peptide fractions (<3 and <10 kDa) of three pea and five grass pea cultivars. The antioxidative properties were determined by three spectrophotometric methods: 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay, Folin‐Ciocalteu (FC) reducing capacity assay and H₂O₂ scavenging. We also applied one luminometric assay for hydroxyl radical scavenging. The study showed that cooking and enzymatic digestion strongly enhanced the release of phenolic compounds in methanolic extracts of four analysed cultivars. Scavenging activity against DPPH radical, hydroxyl radical and hydrogen peroxide was increased in majority of analysed flour specimens subjected to processing. Our findings indicate that, besides the phenolic compounds, the small peptide fraction, especially the MW <3 kDa, in methanolic and aqueous extracts of cooked and digested seed flour significantly contribute to free radical and hydrogen peroxide scavenging activity in all investigated cultivars. Our data strongly suggest that simple cooking treatment and in vitro digestion of seed flour applied prior to extraction with methanol could improve antioxidative activity of obtained extracts.     

Testing the E-Business Infrastructure: Expanding into the Wireless/Mobile Environments

This paper describes the necessity of the third-party testing and monitoring in the field of e-business infrastructure, with the emphasis on expanding into the wireless environments for improvement of the quality of service. Outlining the purpose for monitoring and testing, this paper shows the methods of overwhelming the current problems in the wireless computing, giving statistical and anticipated references for devices that have an active role in mobile environments.