The effect of the diphenylamino side group on the reduction of the molecular interaction between polyurethane copolymer chains

Polyurethane (PU) with a diphenylamino side group is tested for low temperature flexibility at ?30°C and compared with a linear PU without the diphenylamino side group. The PU is composed of 4,4′‐methylenebis(phenylisocyanate) (MDI), poly(tetramethyleneglycol) (PTMG), 1,4‐butanediol (BD), and the diphenylamino group that is grafted to PU chains by a second MDI. The mechanical and shape memory properties of these two types of PU, which differ in the PTMG and the diphenylamino group content, are compared. In the best case, a 306% increase in the maximum stress compared with the linear polymer is attained with a little decrease in the strain. Shape recovery at 45°C increases to 94% and remains ～90% after four cyclic tests. Low temperature flexibility can be improved by increasing the diphenylamino content. The PU with a diphenylamino side group demonstrates the low temperature flexibility at ?30°C, whereas the linear PU must be warmed to room temperature to attain the same degree of flexibility. The exceptional low temperature flexibility is analyzed and is discussed together with the experimental data. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Interactive effects of carbon nanotube and montmorrilonite reinforcement polyvinyl alcohol composite system

This work was conducted to investigate the interactive effect of carbon nanotubes (CNTs) and montmorillonite (MMT) on the mechanical–physical properties of the polyvinyl alcohol (PVOH) nanocomposites. The increasing of CNTs amounts from 0.5 phr to 1 phr has gradually increased tensile strength and Young's modulus of all PVOH/MMT blends due to good interaction effect between MMT and CNTs with PVOH matrix especially for 2 phr MMT added PVOH blends. Besides, the addition of low CNTs amounts (≤1 phr) in PVOH matrix has significantly weakened the hydrogen bonding polymer matrix of all PVOH/MMT blends as evaluated in FTIR analysis. This is attributed to the good of dispersion of low amounts of CNTs could disturb the hydrogen bonding between PVOH molecules and thus induced the strength of O? H stretching in PVOH matrix. However, higher amounts of CNTs (≥1.5 phr) have significantly increased hydrogen bonding in PVOH matrix due to the agglomeration of higher amounts of CNTs particles in PVOH matrix as observed in Fourier transform infrared spectroscopy and scanning electron microscopy analysis. From X‐ray diffraction and transmission electron microscopy observation, the MMT particles were found to effectively exfoliate in PVOH matrix of 2 phr MMT (low amounts) added PVOH/MMT/MCNTs composites, indicates that low MMT amounts could improve the interaction effect between PVOH matrix and CNTs particles. In conclusion, the incorporation of lower amounts of CNTs has effectively improved on the mechanical and physical properties of all PVOH and PVOH/MMT blends. J. VINYL ADDIT. TECHNOL., 26:77–89, 2020. © 2019 Society of Plastics Engineers     

Identification of Protein Markers in Patients Infected with Plasmodium knowlesi,Plasmodium falciparum and Plasmodium vivax

Malaria is caused by parasitic protozoans of the genus Plasmodium and is one of the most prevalent infectious diseases in tropical and subtropical regions. For this reason, effective and practical diagnostic methods are urgently needed to control the spread of malaria. The aim of the current study was to identify a panel of new malarial markers, which could be used to diagnose patients infected with various Plasmodium species, including P. knowlesi, P. vivax and P. falciparum. Sera from malaria-infected patients were pooled and compared to control sera obtained from healthy individuals using the isobaric tags for relative and absolute quantitation (iTRAQ) technique. Mass spectrometry was used to identify serum proteins and quantify their relative abundance. We found that the levels of several proteins were increased in pooled serum from infected patients, including cell adhesion molecule-4 and C-reactive protein. In contrast, the serum concentration of haptoglobin was reduced in malaria-infected individuals, which we verified by western blot assay. Therefore, these proteins might represent infectious markers of malaria, which could be used to develop novel diagnostic tools for detecting P. knowlesi, P. vivax and P. falciparum. However, these potential malarial markers will need to be validated in a larger population of infected individuals.     

Multiplex PCR in Species Authentication: Probability and Prospects—A Review

Food forgery is one of the most articulated socio-economic concerns which contributed to increase people’s awareness on what they eat and how and where it is produced. Consumers are anxious about the consequences of food falsification on their choices, religious rituals, health, and hard-earned fortunes. The recent scandals of horse and rat meats in Europe and China have given us a brainstorming apprehension on the detection, differentiation, and identification of meat products. To restore consumers’ trust and protect wildlife in natural habitats, researchers and policy-making and policy-implementing authorities have massively monitored all steps in the production of foods and food materials. Analytical approaches based on lipids, proteins, and DNA have been proposed for the authentication of meat species under pure and complex matrices. However, protein and lipid-based methods are less effective since the target biomarkers could be modified throughout the processing treatments. On the other hand, DNA-based species identification schemes have gained wider acceptance and reliability because of the superior stability and universality of DNA in all tissues and cells. We systematically presented here major species detection schemes with special emphasis on multiplex polymerase chain reaction (PCR) of both end-point and real-time platforms. We believe this short but comprehensive review would serve as a reference guide for the developers and users of multiplex PCR and others DNA-based techniques.     

High capacity data hiding schemes for medical images based on difference expansion

Since the difference expansion (DE) technique was proposed, many researchers tried to, improve its performance in terms of hiding capacity and visual quality. In this paper, a new scheme, based on DE is proposed in order to increase the hiding capacity for medical images. One of the characteristics of medical images, among the other types of images, is the large smooth regions. Taking advantage of this characteristic, our scheme divides the image into two regions; smooth region and non-smooth region. For the smooth region, a high embedding capacity scheme is applied, while the original DE method is applied to the non-smooth region. Sixteen DICOM images of different modalities were used for testing the proposed schemes. The results showed that the proposed scheme has higher hiding capacity compared to the original schemes.     

The development of life-cycle costing for buildings

The history of the application of life-cycle costing (LCC) began in the UK in the late 1950s and, until now, the state of its development as a concept is not clear. A literature review is presented that shows the changing approaches to LCC by drawing on four major academic journals and 45 peer-reviewed papers. The review verifies that there is a revival of interest in using LCC in tandem with other life-cycle methodologies for research on sustainable building. It also presents a set of methods that are applicable to model and estimate the life-cycle costs of ‘conventional’ and ‘green’ buildings with the objective of distinguishing them. Through the information gathered, it provides a centralized source of reference for the assumptions used in LCC calculations concerning some key input parameters. The finding shows an increasing trend of publications on the evaluation of economic options for green building designs and performance. The directions are clear that the concepts and methods have to evolve to a state where they will help to integrate and optimize economic, social and environmental considerations to deliver more sustainable built environments in the future.     

Thermal properties and processability of talc‐ and calcium carbonate‐filled poly(vinyl chloride) hybrid composites

The main objective of this investigation was to study and compare the thermal rigidity, thermal stability, and processability of poly(vinyl chloride) (PVC) composites filled with single fillers of talc and uncoated ground CaCO₃ (SM 90) or a hybrid filler consisting of talc/SM 90. To produce the composites, the PVC resin, fillers, and other additives were dry‐blended in a laboratory mixer before being milled into sheets by using a two‐roll mill. Test specimens were prepared by compression molding, after which the thermal properties and processability of the composites were determined. Single and hybrid filler loadings used were fixed at 30 phr (parts per hundred parts of resin). Talc‐filled PVC composite showed slightly better thermal stability and rigidity than the composite filled with SM 90, and its thermal stability and rigidity slightly decreased with SM 90 content increasing from 5 to 25 phr in order to replace talc filler in the hybrid composites. The fusion time of talc‐filled PVC composite was shorter than that of SM 90‐filled PVC composite; thus, the fusion time of hybrid composites increased with increasing SM 90. The fusion torque showed an opposite behavior. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers     

Electron Beam Irradiation to Recrosslink Devulcanized Sulfur Cured Rubber Blended Polypropylene

This study aims to investigate the effect electron beam (EB) irradiation on the polypropylene/devulcanized sulfur cured rubber (PP‐DVC) compound. The PP‐DVC compounds were compounded using twin‐screw extruder and then compression molded into required shapes before irradiation begins. The gel content of all irradiated PP‐DVC compounds gradually increased with higher irradiation dose indicated that the presence of DVC plays an important role in crosslinking enhancement. The mechanical properties of PP‐DVC compounds were observed marginally higher at low irradiation dosages (≤50 kGy). However, higher irradiation dosages up to 200 kGy cause adverse effect to the PP‐DVC compounds. In addition, the application of low irradiation dosage could enhance the dispersion of DVC particles at 20 phr composition in PP matrix. This also found that the scanning electron microscopy (SEM) observation where the DVC particles dispersed better in PP matrix compared to that of nonirradiated samples. Further increment in irradiation dosages up to 200 kGy reduced the crystallinity caused by chain scissoring process could rupture the crystalline structure in PP matrix. It was also found that the wavenumber of the C? H and CH₂ groups for irradiated samples reduced at high irradiation dosages due to the formation of carbonyl group. POLYM. ENG. SCI., 59:1017–1027, 2019. © 2019 Society of Plastics Engineers     

Comparison of catalyst-coated membranes and catalyst-coated substrate for PEMFC membrane electrode assembly:A review

Catalyst-coated membranes (CCMs) have gained popularity among membrane electrode assembly (MEA) fabri-cators for their abilities and advantages compared with those of other methods, such as catalyst-coated sub-strates (CCSs). CCMs show a profound new analysis for reducing platinum (Pt) catalyst loading. In addition, they increase the total number of reactions that occur on the MEA because of their active area amplification, which leads to an improved catalyst-utilization efficiency rate. Moreover, several characteristics are involved in the MEA fabrication methods. Material-manufacturing effects with regard to catalyst inks and analysis of the overall performance of MEAs prepared by the CCM and CCS methods are deliberated. This deliberation empha-sizes the practical approaches in minimizing performance deterioration during the fabrication of MEAs using the CCM method and converses the commercialization of the CCM fabrication method toward developing an end product. Novel research is required for MEA fabrication using the CCM methods to ensure that the fuel cell performance is improved. Therefore, this review is focusing on the pros and cons of both distinguished methods, that is, CCM and CCS fabrication, for better comparison.     

In Vivo Efficacy of Neutrophil-Mediated Bone Regeneration Using a Rabbit Calvarial Defect Model

Reconstruction of bone due to surgical removal or disease-related bony defects is a clinical challenge. It is known that the immune system exerts positive immunomodulatory effects on tissue repair and regeneration. In this study, we evaluated the in vivo efficacy of autologous neutrophils on bone regeneration using a rabbit calvarial defect model. Methods: Twelve rabbits, each with two surgically created calvarial bone defects (10 mm diameter), were randomly divided into two groups; (i) single application of neutrophils (SA-NP) vs. SA-NP control, and (ii) repetitive application of neutrophils (RA-NP) vs. RA-NP control. The animals were euthanized at 4 and 8 weeks post-operatively and the treatment outcomes were evaluated by micro-computed tomography, histology, and histomorphometric analyses. Results: The micro-CT analysis showed a significantly higher bone volume fraction (bone volume/total volume) in the neutrophil-treated groups, i.e., median interquartile range (IQR) SA-NP (18) and RA-NP (24), compared with the untreated controls, i.e., SA-NP (7) and RA-NP (14) at 4 weeks (p < 0.05). Similarly, new bone area fraction (bone area/total area) was significantly higher in neutrophil-treated groups at 4 weeks (p < 0.05). Both SA-NP and RA-NP had a considerably higher bone volume and bone area at 8 weeks, although the difference was not statistically significant. In addition, immunohistochemical analysis at 8 weeks revealed a higher expression of osteocalcin in both SA-NP and RA-NP groups. Conclusions: The present study provides first hand evidence that autologous neutrophils may have a positive effect on promoting new bone formation. Future studies should be performed with a larger sample size in non-human primate models. If proven feasible, this new promising strategy could bring clinical benefits for bone defects to the field of oral and maxillofacial surgery.