From the web of data to a world of action

This paper takes as its premise that the web is a place of action, not just information, and that the purpose of global data is to serve human needs. The paper presents several component technologies, which together work towards a vision where many small micro-applications can be threaded together using automated assistance to enable a unified and rich interaction. These technologies include data detector technology to enable any text to become a start point of semantic interaction; annotations for web-based services so that they can link data to potential actions; spreading activation over personal ontologies, to allow modelling of context; algorithms for automatically inferring ‘typing’ of web-form input data based on previous user inputs; and early work on inferring task structures from action traces. Some of these have already been integrated within an experimental web-based (extended) bookmarking tool, Snip!t, and a prototype desktop application On Time, and the paper discusses how the components could be more fully, yet more openly, linked in terms of both architecture and interaction. As well as contributing to the goal of an action and activity-focused web, the work also exposes a number of broader issues, theoretical, practical, social and economic, for the Semantic Web.     

Development of a novel bioactive packaging based on the incorporation of Lactobacillus sakei into sodium-caseinate films for controlling Listeria monocytogenes in foods

A novel packaging technology was developed based on the incorporation of Lactobacillus sakei cells into sodium-caseinate (SC) edible films. Incorporation was based either on direct addition of the cells in the film forming solution used for casting or by surface spraying of the culture on the preformed film, resulting in a population density of 10⁶ cfu/cm². Addition of sorbitol in the film matrix increased the viability of the cells, greater than 90%, upon storage under both refrigeration and ambient temperature conditions for 30 days. Incorporation of the viable protective culture did not affect the mechanical properties and the physico-chemical properties of the film. Application of the films to both laboratory medium (agar) and a food model system (fresh beef) inoculated with Listeria monocytogenes resulted in a rapid growth of L. sakei immobilized in the film following contact with the wet medium or the food surface and a significant inhibition of the pathogen growth compared to the control samples under both constant and dynamic storage temperature protocols. The present study indicated that biopolymer-based antimicrobial films containing cells of a protective culture can be used as an effective packaging technology for improving food safety.     

Simple MOS‐based circuit designed to show pinched hysteresis behavior

We propose and validate a simple 3‐transistor MOS circuit that shows an all‐positive pinched hysteresis behavior. Complete analysis of the circuit is provided along with experimental results using a commercial CMOS transistor array.     

Tribological performance of hybrid organo-silicate coatings

Hybrid organo-silicate coatings (hybrid coatings) present many advantages and find use in many applications. However, their tribological performance has not been widely investigated due to the non-uniformity of the synthesized hybrid materials. In this work, nanoscratch tests have been employed for the investigation of wear mechanisms and organic–inorganic coatings adhesion. The tribological performance was investigated under low applied normal forces, in order to estimate the coefficient of friction (μ) values, the coatings resistance and the humidity effect when the synthesized coatings were submerged on a cell culture medium. Also, the performed plastic deformation was correlated with the experimental data and the surface images taken with a scanning probe microscope after the scratch tests. Furthermore, the experimental data were fitted and the relative coefficient of friction and cohesive force of each synthesized coating were calculated, since organic and hybrid materials do not conform with the classic tribology laws and are greatly affected by the adhesion forces observed between tip and sample's surface.     

From directed evolution to computational enzyme engineering—A review

Nature relies on a wide range of enzymes with specific biocatalytic roles to carry out much of the chemistry needed to sustain life. Enzymes catalyze the interconversion of a vast array of molecules with high specificity—from molecular nitrogen fixation to the synthesis of highly specialized hormones and quorum-sensing molecules. Ever increasing emphasis on renewable sources for energy and waste minimization has turned enzymes into key industrial workhorses for targeted chemical conversions. Modern enzymology is central to not only food and beverage manufacturing processes but also finds relevance in countless consumer product formulations such as proteolytic enzymes in detergents, amylases for excess bleach removal from textiles, proteases in meat tenderization, and lactoperoxidases in dairy products. Herein, we present an overview of enzyme science and engineering milestones and the emergence of directed evolution of enzymes for which the 2018 Nobel Prize in Chemistry was awarded to Dr. Frances Arnold.     

A Degron Blocking Strategy Towards Improved CRL4CRBN Recruiting PROTAC Selectivity**

Small molecules inducing protein degradation are important pharmacological tools to interrogate complex biology and are rapidly translating into clinical agents. However, to fully realise the potential of these molecules, selectivity remains a limiting challenge. Herein, we addressed the issue of selectivity in the design of CRL4^CRBN recruiting PROteolysis TArgeting Chimeras (PROTACs). Thalidomide derivatives used to generate CRL4^CRBN recruiting PROTACs have well described intrinsic monovalent degradation profiles by inducing the recruitment of neo-substrates, such as GSPT1, Ikaros and Aiolos. We leveraged structural insights from known CRL4^CRBN neo-substrates to attenuate and indeed remove this monovalent degradation function in well-known CRL4^CRBN molecular glues degraders, namely CC-885 and Pomalidomide. We then applied these design principles on a previously published BRD9 PROTAC (dBRD9-A) and generated an analogue with improved selectivity profile. Finally, we implemented a computational modelling pipeline to show that our degron blocking design does not impact PROTAC-induced ternary complex formation. We believe that the tools and principles presented in this work will be valuable to support the development of targeted protein degradation.     

Mathematical modelling of enzymatically cross-linked polymer–phenol conjugates using deterministic and stochastic methods

In this study, two different modelling approaches, namely, a deterministic and a stochastic one, are developed to model the enzymatic cross-linking of polymer–phenol conjugates. A comprehensive kinetic mechanism is postulated to describe the elementary reactions in the cross-linking of polymer–phenol chains in the presence of the horseradish peroxidase (HRP)–H₂O₂ initiation system. In the first approach, a moments-based model is derived to account for the conservation of all molecular species and leading moments of the number chain length distribution (NCLD) in the reactive system. In the second approach, a stochastic Monte Carlo kinetic model is formulated to follow the time evolution of a sample of cross-linkable polymer chains and calculate the weight chain length distribution (WCLD). From the numerical solutions of both models, the dynamic evolution of the concentrations of all the reactive species, the gelation onset time, the sol and gel mass fractions as well as the number and weight average molecular weights of the cross-linkable polymer chains are calculated. The two derived models are validated using experimental kinetic measurements on the enzymatic cross-linking of tyramine-modified hyaluronic acid and carboxymethyl-chitin. It is shown that both models can accurately predict the gelation onset time of the two cross-linkable systems over a wide range of variations in HRP and H₂O₂ concentrations. Finally, the MC model predictions on the weight average number of polymer chains in the cross-linked molecules are compared to Flory's analytical solution on the tetrafunctional cross-linking of polymer chains of uniform length.     

The quality‐constrained scheduling problem in plastics compounding

Interest is increasing in plastic compounding plants that offer tailor‐made resins. Such plants produce a wide range of products in small quantities and with frequent changeovers. The underlying scheduling problem has been extensively researched; however, the concept of incorporating qualities of the finished product in the problem of plastics compounding has not been considered. We express product qualities as an additional problem constraint so that the production schedule ensures product quality. The additional constraint makes this mixed integer nonlinear program (MINLP) problem more difficult to solve. Several case studies are solved to illustrate the utility of the proposed approach. Experiments demonstrated that qualities of the finished product can be ensured a priori if the appropriate relations are developed and integrated in the optimisation model. As well, this paper provides insight into the economic aspects of the scheduling problem under consideration. Experiments showed that none of the cost components (operation, raw material, inventory, penalty or utilities) can alone play the role of the optimisation criterion. © 2012 Canadian Society for Chemical Engineering     

A new fluidized bed coating process via photo‐initiated cationic polymerization

An ultraviolet (UV) photo‐polymerization particle coating process was developed by coupling the photo‐initiated cationic polymerization with the fluidized bed coating techniques. Unlike the conventional air‐suspension coating in the fluidized bed, the new process employs a UV curable composition instead of a solvent/water‐borne system as a coating material, which has a rapid curing rate and virtually no inhibition to oxygen and moisture. A modified fluidized bed coater equipped with a quartz window allows UV light to penetrate and to initiate the curing of photo‐sensitive polymerizable chemicals coated on the particles. A UV‐curable liquid composed of cycloaliphatic epoxide, oxetane, and triarylsulfonium cationic photo‐initiator was specifically formulated for the fluidized bed particle coating process. A systematic experimental approach including photo‐Differential Scanning Calorimetry, Fourier Transform Infrared Spectroscopy, and tackiness measurements has been developed to characterize the curing mechanism of the cationic UV curable formulations and to optimize the chemical compositions. The effects of the UV curable chemicals, viscosity of coating liquid, and the fluidization operating conditions on the physical properties of coated particles have been thoroughly investigated. Under optimized conditions, this novel process is very efficient as follows: particles can be coated very rapidly with ultra‐thin films of the cured chemicals, with little, if any, formation of particulate agglomeration. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Stereoselective Epoxidation of Alkenes with Hydrogen Peroxide using a Bipyrrolidine‐Based Family of Manganese Complexes

Novel manganese complexes containing N₄‐tetradentate ligands derived from chiral bipyrrolidinediamines catalyze the stereoselective epoxidation of a wide array of alkenes using low catalyst loadings (0.1 mol%) and hydrogen peroxide (1.2 equiv.) as terminal oxidant. This family of catalysts affords good to excellent yields (80–100%) and moderate to good ees (40–73%) in short reaction times (30 min) making efficient use of hydrogen peroxide.