Peptide–Peptide Co-Assembly: A Design Strategy for Functional Detection of C-peptide,A Biomarker of Diabetic Neuropathy

Diabetes-related neuropathy is a debilitating condition that may be averted if it can be detected early. One possible way this can be achieved at low cost is to utilise peptides to detect C-peptide, a biomarker of diabetic neuropathy. This depends on peptide-peptide co-assembly, which is currently in a nascent stage of intense study. Instead, we propose a bead-based triple-overlay combinatorial strategy that can preserve inter-residue information during the screening process for a suitable complementary peptide to co-assemble with C-peptide. The screening process commenced with a pentapeptide general library, which revealed histidine to be an essential residue. Further screening with seven tetrapeptide focused libraries led to a table of self-consistent peptide sequences that included tryptophan and lysine at high frequencies. Three complementary nonapeptides (9mer com-peptides), wpkkhfwgq (Trp-D), kwkkhfwgq (Lys-D), and KWKKHFWGQ (Lys-L) (as a negative control) were picked from this table for co-assembly studies with C-peptide. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) and circular dichroism (CD) spectroscopies were utilized to study inter-peptide interactions and changes in secondary structures respectively. ATR-FTIR studies showed that there is indeed inter-peptide interaction between C-peptide and the tryptophan residues of the 9mer com-peptides. CD studies of unaggregated and colloidal C-peptide with the 9mer com-peptides suggest that the extent of co-assembly of C-peptide with Trp-D is greatest, followed by Lys-D and Lys-L. These results are promising and indicate that the presented strategy is viable for designing and evaluating longer complementary peptides, as well as complementary peptides for co-assembly with other polypeptides of interest and importance. We discuss the possibility of designing complementary peptides to inhibit toxic amyloidosis with this approach.     

Effects of Neodymium and Calcium on the Thermal Stability of AZ71 Magnesium Alloys

The effects of an addition of 0–2 wt% Nd on thermal stability of 0–3 wt% Ca-containing modified AZ71 magnesium alloys was investigated. The ignition temperature was found to increase from that of AZ71, 574, to 825 °C with the addition of 0.5 wt% Ca and 1 wt% Nd. The ignition temperature was further increased to 1114 °C when 3 wt% Ca was added. The Ca- and Nd-added AZ71 was isothermally maintained at a temperature of 500 °C in air for 12 h. The MgO–CaO–Nd₂O₃ formed on the surface to improve the thermal stability of the AZ71–xCa–yNd alloys. While both the tensile strength and ductility decreased with the Ca concentration in the alloy, an addition of 1 wt% Nd was found able to alleviate the degradation effects of Ca on the tensile strength and ductility at 170 °C. Both solid solution formation and precipitation strengthening contributed to the increase in toughness. AZ71 containing 0.5–2 wt% Ca and 1 wt% Nd provides the optimum combination of ignition resistance and mechanical properties.     

Structural properties and sensing performance of CeTiO3 ceramic films as a solid-state pH sensor

In this paper, we have studied the impact of postannealing treatment on the structural properties and sensing characteristics of CeTiO₃ ceramic membranes deposited on Si substrate by sputtering for solid-state electrolyte-insulator-semiconductor (EIS) pH sensors. X-ray photoelectron spectroscopy, Auger electron spectroscopy, X-ray diffraction, and atomic force microscopy were used to study the chemical compositions, elemental depth profiles, film structures, and surface morphologies of CeTiO₃ ceramic membranes treated at three rapid thermal annealing (RTA) temperatures of 700, 800 and 900?°C. The sensing performance of the CeTiO₃ ceramic membranes annealed at three different RTA temperatures is strongly correlated to their structural properties. The CeTiO₃ EIS device after RTA at 800?°C exhibited the best sensing characteristics (pH sensitivity, hysteresis voltage and drift rate) among these RTA temperatures. We attribute this behavior to the optimal RTA temperature enhancing the Ce³⁺/Ce⁴⁺ ratio of CeTiO₃ ceramic membrane, reducing an interfacial layer at the CeTiO₃-Si interface, and increasing its surface roughness.     

Similarities and differences between male and female novice designers on color‐concept associations for warnings,action required,and signs and equipment status messages

This research examined the male and female novice designers toward color associations for the concepts used for ‘warnings’, ‘action required’, and ‘signs and equipment status’ through a questionnaire‐based study. A total of 178 Hong Kong Chinese final year undergraduate design students (89 males and 89 females) participated in the study. The test used required the participants to indicate their choice of one of nine colors to associations with each of 38 concepts in a color‐concept table, so that any one color could be associated with any one of the concepts. For both male and female groups of novice designers, chi‐square tests revealed a strong color association for each concept tested in this study (P < .05). The results showed males and females agreed on some color‐concept association stereotypes which were therefore gender neutral. The male and female novice designers had the same color associations and similar levels of stereotype strengths for 21 concepts. The nine strongest and therefore most useful color‐concept association stereotypes for both male and female novice designers were: red‐danger, red‐fire, red‐hot, red‐stop, red‐emergency, red‐error, blue‐cold, blue‐male, and green‐exit. However, the male and female novice designers had different color association stereotypes for the standby (green vs. yellow), emergency exit (green vs. red), and toxic (purple vs. black) concepts, and the strengths of the 14 remaining associations for both groups were not at equivalent levels. Overall, it is anticipated that the findings of this study will act as a useful reference for novice designers and other design practitioners to optimize color coding in the design of ‘warnings’, ‘action required’, and ‘signs and equipment status’ messages.     

Multimodal sensing and active continuous closed‐loop feedback for achieving reliable manipulation in the outdoor physical world

The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition.     

Bacterium‐Templated Polymer for Self‐Selective Ablation of Multidrug‐Resistant Bacteria

The recognition and inactivation of specific pathogenic bacteria remain an enormous scientific challenge and an important therapeutic goal. Therefore, materials that can selectively target and kill specific pathogenic bacteria, without harming beneficial strains are highly desirable. Here, a material platform is reported that exploits bacteria as a template to synthesize polymers with aggregation‐induced emission (AIE) characteristic by copper‐catalyzed atom transfer radical polymerization for self‐selective killing of the bacteria that templates them with no antimicrobial resistance. The bacteria‐templated polymers show very weak fluorescence in aqueous media, however, the fluorescence is turned on upon recognition of the bacteria used as the template to synthesize the polymer even at a low concentration of 600 ng mL^?1. Moreover, the incorporated AIE fluorogens (AIEgens) can act as an efficient photosensitizer for reactive oxygen species (ROS) generation after bacteria surface binding, which endows the templated polymers with the capability for selective bacterial killing. The bacterium‐templated synthesis is generally applicable to a wide range of bacteria, including clinically isolated multidrug‐resistant bacterial strains. It is envisioned that the bacterium‐templated method provides a new strategy for bacteria‐specific diagnostic and therapeutic applications.     

Multi-objective particle swarm optimisation based integrated production inventory routing planning for efficient perishable food logistics operations

Sustainable and efficient food supply chain has become an essential component of one’s life. The model proposed in this paper is deeply linked to people's quality of life as a result of which there is a large incentive to fulfil customer demands through it. This proposed model can enhance food quality by making the best possible food quality accessible to customers, construct a sustainable logistics system considering its environmental impact and ensure the customer demand to be fulfilled as fast as possible. In this paper, an extended model is examined that builds a unified planning problem for efficient food logistics operations where four important objectives are viewed: minimising the total expense of the system, maximising the average food quality along with the minimisation of the amount of CO₂ emissions in transportation along with production and total weighted delivery lead time minimisation. A four objective mixed integer linear programming model for intelligent food logistics system is developed in the paper. The optimisation of the formulated mathematical model is proposed using a modified multi-objective particle swarm optimisation algorithm with multiple social structures: MO-GLNPSO (Multi-Objective Global Local Near-Neighbour Particle Swarm Optimisation). Computational results of a case study on a given dataset as well as on multiple small, medium and large-scale datasets followed by sensitivity analysis show the potency and effectiveness of the introduced method. Lastly, there has been a scope for future study displayed which would lead to the further progress of these types of models.