Hydrothermally extracted nanohydroxyapatite from bovine bone as bioceramic and biofiller in bionanocomposite

Bones have an extraordinary capacity to restore and regenerate in case of minor injury. However, major injuries need orthopedic surgeries that required bone implant biomaterials. In this study, n-HAP powder was extracted from bovine bone by hydrothermal and calcined at different calcination temperatures (600-1100°C) without the use of solvents. The n-HAP powders produced were used to fabricate two types of biomaterials (HAP bioceramics and PLA/n-HAP bionanocomposite). The raw-HAP and calcined n-HAP powder samples were compacted into green bodies and were sintered at various temperatures (1000-1400°C) to produce HAP bioceramics. The best calcined n-HAP was mixed with PLA by melt mixing and injection moulding to fabricate PLA/n-HAP bionanocomposite. Characterizations of the n-HAP powder, n-HAP bioceramics and PLA/n-HAP bionanocomposite samples were done by Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transforms infrared (FTIR), Field emission scanning electron microscopy (FESEM), Energy-dispersive x-ray spectroscopy (EDX), X-ray fluorescence (XRF) spectroscopy, universal testing machine (UTM) and melt flow index (MFI) analyses. TGA data revealed that n-HAP was thermally stable at 1300ºC. The extracted n-HAP powder was highly crystalline and crystallite size was in the range of 10-83 nm as confirmed by XRD. Density and hardness of the n-HAP bioceramics increased as sintering temperature increased and showing maximum values at a temperature of 1400°C. The results of PLA/n-HAP bionanocomposite revealed that the higher n-HAP loaded (at 5wt%), the lower the tensile strength of bionanocomposite due to poor interfacial adhesion. The interfacial adhesion was improved by loading of 1.0 wt% maleic anhydride (MAH) as a compatibilizer. The biocompatibility of bionanocomposite was evaluated in simulated body fluids (SBF). The results showed that apatite layers were grown on the surfaces of both biomaterials. Therefore, both biomaterials formulated shall be promising medical biomaterials for orthopedic applications

Intra-industry trade and trade intensities: Evidence from New Zealand

This study analyses the development of intra-industry and inter industry trade between New Zealand, Australia, and the selected Asia-Pacific nations during the period 1990 to 2000. The study adapts mainly two approaches to examine these developments. First, an historical analysis of New Zealand trading patterns is presented. For this purpose, intra-industry trade development is examined. The Grubel-Lloyd and Aquino indices are used to calculate the intensity of intra- industry trade at the 3-digit SITC levels to determine the relative importance of intra-industry trade as opposed to inter-industry trade. IIT has been estimated across industries and for selected trading partners. A time series approach is used to estimate any trend in the ratio of intra industry trade to total trade in relation to Australia. Secondly, the paper examines the strength of trade relations between New Zealand and the other countries. For this purpose the intensity of trade index has been estimated for bilateral trade flows between these nations. These analyses are examined to consider how trade has changed in this period of trade liberalisation. The results show that intra-industry trade has increased between New Zealand and Australia. The results also suggest that bilateral trade flows between New Zealand, Australia and other countries has become more intense indicating trading relations are strengthening. In some cases bilateral trade flows have decreased. The results also suggest that the removal of trade barriers through bilateral and multilateral negotiations has positive impacts on intra-industry trade and the intensity of trade of these economies

Aisha Bano - The Role of KCNQ (Kv7) Potassium Channels in Schizophrenia Deficits

For years, studies have been conducted to treat the positive and negative symptoms and cognitive deficits of schizophrenia; it has allowed to treat the positive symptoms through regulation of dopaminergic neurons and dopamine pathways; however, we still do not know how to treat the negative symptoms and cognitive deficits. The reason we cannot treat them is due to a lack of adequate understanding of the underlying pathology which manifests itself in the behavior. Over the years, there have been multiple proposed hypotheses regarding the underlying pathology, and accordingly, medication were developed to regulate the variety of pathways in the brain but each of them has failed. Under the mentorship of Dr. Behnam Ghasemzadeh, experiments are being conducted to regulate the activity of KCNQ potassium ion channel to ameliorate the negative symptoms and cognitive deficits of schizophrenia. The experiments are being conducted using animal-models of schizophrenia like-effect. The results suggest that decrease in the activity of the KCNQ potassium channels, leading to an increase in the neuronal activity, may be able to treat the symptoms of schizophrenia.https://epublications.marquette.edu/mcnair_2013/1007/thumbnail.jp

ASEAN-New Zealand trade relations and trade potential

This paper explores trade development by the Association of South East Asian Nations (ASEAN) with a particular reference to New Zealand and in the context of free trade agreements and partnerships. It describes the history of ASEAN, its trade composition, diversity and intensity. The paper includes an analysis of Kojima indices of trade intensities, the trade potential index and a gravity trade model using panel data and multivariate analysis. Hypotheses derived from trade theories are then tested to identify the key determinants of trade and the implications for policy. Overall, the study shows that economic integration has had a positive impact on ASEAN nations and with New Zealand and with ongoing potential

New Zealand kiwifruit export performance: Market analysis and revealed comparative advantage

This paper investigates the spectacular and successful growth of New Zealand kiwifruit production and exports between 1984 and 2009. It explores the evolution, current status, future prospects and challenges facing the industry where more than 90 percent of the output is exported. The study includes a statistical analysis of the production and consumption of kiwifruit in New Zealand and other countries, with a particular focus on Asia. The product life-cycle model is used to examine the pattern of evolution of New Zealand’s kiwifruit industry while revealed comparative advantage methodology is used to determine whether New Zealand has a comparative advantage in kiwifruit. Finally, econometric analysis is employed to identify and test the strength of key determinants of kiwifruit exports. Empirical analysis suggests that domestic and trading partner incomes, market size and distance are key determinants of kiwifruit export performance

On openness and real exchange rate volatility

We address the puzzle concerning the inverse relationship between openness and real exchange rate volatility. We argue that the relationship can be explained by increased openness facilitating purchasing power parity. Using New Zealand data, we show that increased openness prolongs real exchange regimes characterised by fast mean-reversion and low volatility

On openness and real exchange rate volatility

We address the puzzle concerning the inverse relationship between openness and real exchange rate volatility. We argue that the relationship can be explained by increased openness facilitating purchasing power parity. Using New Zealand data, we show that increased openness prolongs real exchange regimes characterised by fast mean-reversion and low volatility.

Illuminating an Ecosystem of Partisan Websites

This paper aims to shed light on alternative news media ecosystems that are believed to have influenced opinions and beliefs by false and/or biased news reporting during the 2016 US Presidential Elections. We examine a large, professionally curated list of 668 hyper-partisan websites and their corresponding Facebook pages, and identify key characteristics that mediate the traffic flow within this ecosystem. We uncover a pattern of new websites being established in the run up to the elections, and abandoned after. Such websites form an ecosystem, creating links from one website to another, and by `liking' each others' Facebook pages. These practices are highly effective in directing user traffic internally within the ecosystem in a highly partisan manner, with right-leaning sites linking to and liking other right-leaning sites and similarly left-leaning sites linking to other sites on the left, thus forming a filter bubble amongst news producers similar to the filter bubble which has been widely observed among consumers of partisan news. Whereas there is activity along both left- and right-leaning sites, right-leaning sites are more evolved, accounting for a disproportionate number of abandoned websites and partisan internal links. We also examine demographic characteristics of consumers of hyper-partisan news and find that some of the more populous demographic groups in the US tend to be consumers of more right-leaning sites.Comment: Published at The Web Conference 2018 (WWW 2018). Please cite the WWW versio