Alumina/multiwalled carbon nanotube (MWNT) composites with different MWNT contents ranging from 0.5to10vol% were prepared by spark plasma sintering technique. The dc electrical conductivity and dielectric properties of the composites were investigated and percolation theory was applied to demonstrate the electrical property transition from insulator to conductor. The experimental results have shown that the electrical conductivity increased sharply as the content of MWNTs was close to percolation threshold of 0.79vol%. In the low frequency range, the dielectric constant reached as high as 5000 when the content of MWNTs was at 1.74vol% and nearly frequency independent.

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Developing a cost-effective and highly efficient electrocatalyst with superior catalytic activity is crucial for clean and green water splitting, including the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and the oxygen reduction reaction (ORR). The single-atom catalyst (SAC) is a breakthrough in industrial catalysis because of the advantages of maximum metal atom utilization, single active sites, strong metal−support interactions, and great potential to accomplish high catalytic performance and selectivity. Herein, we investigate the electrocatalytic performance of a series of SACs supported on a phosphomolybdic acid (PMA) cluster for the HER, OER, and ORR by using first-principles-based calculations. It has been found that the most plausible binding site for the single-metal adatoms is the 4-fold hollow (4H) site over the PMA cluster. Due to the higher stability and catalytic activity of single-metal adatoms, fast electron transfer kinetics is permissible through catalysis. Mainly, Pt 1 /PMA, Ru 1 /PMA, V 1 /PMA, and Ti 1 /PMA realized decent catalytic performance toward the HER due to nearly ideal (ΔG H* = 0) ΔG H* values via the Volmer−Heyrovsky pathway. The Co 1 /PMA (0.45 V) and Pt 1 /PMA (0.49 V) can be active and selective catalysts for the OER with their overpotentials comparable those of to MoC 2 , IrO 2 , and RuO 2 . Among the considered candidates, a non-noble metal Fe 1 /PMA SAC is a promising electrocatalyst for the ORR with an overpotential of 0.42 V, which is lower than that for the most favorable Pt (0.45 V) catalyst. Furthermore, Pt 1 /PMA is an auspicious multifunctional electrocatalyst for overall water splitting (−0.02 V for the HER and 0.49 V for the OER) and a metal-air battery (0.79 V for the ORR) catalyst. The current study is further extended to calculate the kinetic potential energy barrier for the excellent catalytic performance of Co 1 for the OER and Fe 1 for the ORR. The results suggest that the kinetic activation barrier values in all proton-coupled electron transfer steps are in good agreement with the thermodynamic results. It was revealed that the PMA cluster is a promising single-atom support for the HER, OER, and ORR and provides low-cost and highly efficient electrocatalytic activity under normal reaction conditions.

The objective of this study was to identify DNA markers in the 4 casein genes (CSN1S1, CSN1S2, CSN2, and CSN3) and the 2 major whey protein genes (LALBA and LGB) that show associations with milk protein profile measured by reverse-phase HPLC. Fifty-three single nucleotide polymorphisms (SNP) were genotyped for cows in a unique resource population consisting of purebred Holstein and (Holstein × Jersey) × Holstein crossbred animals. Seven traits were analyzed, including concentrations of α(S)-casein (CN), β-CN, κ-CN, α-lactalbumin, β-lactoglobulin, and 2 additional secondary traits, the total concentration of the above 5 milk proteins and the α(S)-CN to β-CN ratio. A substantial fraction of phenotypic variation could be explained by the additive genetic component for the 7 milk protein composition traits studied. Moreover, several SNP were significantly associated with all examined traits at an experiment-wise error rate of 0.05, except for α-lactalbumin. Importantly, the significant SNP explained a large proportion of the phenotypic variation of milk protein composition. Our findings could be used for selecting animals that produce milk with desired composition or desired processing and manufacturing properties.

Organizations are becoming increasingly aware of the importance of knowledge sharing to survive and remain competitive. Current knowledge sharing models have been found to be lacking as they only focus on the relationships between factors that influence knowledge sharing. An integrated approach that is capable of a simultaneous investigation of the various factors that affect knowledge sharing initiatives, quality of knowledge management and its impact on organizational performance has not been widely attempted. This study aims to develop a holistic knowledge sharing model for the public sector in Malaysia that is based on an integrated approach, which combines factors that influence knowledge management (input), knowledge sharing quality (process) and workers’ performance as well as service delivery (output) that encompasses the individual, organization and technology. This study will firstly present a review of the literature of current models in knowledge sharing, which will then form the take-off point for the development of the proposed holistic model. Such a holistic model is deemed appropriate and necessary to steer knowledge sharing initiatives in tandem with forming the base for policy-making of such initiatives.

Introduction: Facilitating stroke survivors and their caregivers to lead a fulfilling life after stroke requires service providers to think about their different needs. Poor post stroke care may lead to unmet needs in stroke survivors and stroke caregivers. This may compromise them in leading their lives optimally after stroke. Objectives & Methodology: This systematic narrative review examines articles published from 1990 to 2017, generated from Ovid, MEDLINE, CINAHL, and PubMed. The search was also supplemented by an examination of reference lists for related articles via Scopus. We included 105 articles. Findings: We found that the type of unmet needs in stroke survivors and the contributing factors were substantially different from their caregivers. The unmet needs in stroke survivors ranged from health-related needs to re-integration into the community; while the unmet needs in stroke caregivers ranged from information needs to support in caring for the stroke survivors and caring for themselves. Additionally, the unmet needs in both groups were associated with different factors. Conclusion: More research is required to understand the unmet needs of stroke survivors and stroke caregivers to improve the overall post-stroke care services.

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