bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient and Security Enhanced Anonymous Authentication with Key Agreement Scheme in Wireless Sensor Networks
Authors: Jung Jaewook , Moon Jongho , Lee Donghoon , Won Dongho
Published: March 2017

At present, users can utilize an authenticated key agreement protocol in a Wireless Sensor Network (WSN) to securely obtain desired information, and numerous studies have investigated authentication techniques to construct efficient, robust WSNs. Chang et al. recently presented an authenticated key agreement mechanism for WSNs and claimed that their authentication mechanism can both prevent various types of attacks, as well as preserve security properties. However, we have discovered that Chang et al’s method possesses some security weaknesses. First, their mechanism cannot guarantee protection against a password guessing attack, user impersonation attack or session key compromise. Second, the mechanism results in a high load on the gateway node because the gateway node should always maintain the verifier tables. Third, there is no session key verification process in the authentication phase. To this end, we describe how the previously-stated weaknesses occur and propose a security-enhanced version for WSNs. We present a detailed analysis of the security and performance of our authenticated key agreement mechanism, which not only enhances security compared to that of related schemes, but also takes efficiency into consideration.
Application of a MEMS-Based TRNG in a Chaotic Stream Cipher
Authors: Garcia-Bosque Miguel , Pérez Adrián , Sánchez-Azqueta Carlos , Celma Santiago
Published: March 2017

In this work, we used a sensor-based True Random Number Generator in order to generate keys for a stream cipher based on a recently published hybrid algorithm mixing Skew Tent Map and a Linear Feedback Shift Register. The stream cipher was implemented and tested in a Field Programmable Gate Array (FPGA) and was able to generate 8-bit width data streams at a clock frequency of 134 MHz, which is fast enough for Gigabit Ethernet applications. An exhaustive cryptanalysis was completed, allowing us to conclude that the system is secure. The stream cipher was compared with other chaotic stream ciphers implemented on similar platforms in terms of area, power consumption, and throughput.
Activity Recognition and Semantic Description for Indoor Mobile Localization
Authors: Guo Sheng , Xiong Hanjiang , Zheng Xianwei , Zhou Yan
Published: March 2017

As a result of the rapid development of smartphone-based indoor localization technology, location-based services in indoor spaces have become a topic of interest. However, to date, the rich data resulting from indoor localization and navigation applications have not been fully exploited, which is significant for trajectory correction and advanced indoor map information extraction. In this paper, an integrated location acquisition method utilizing activity recognition and semantic information extraction is proposed for indoor mobile localization. The location acquisition method combines pedestrian dead reckoning (PDR), human activity recognition (HAR) and landmarks to acquire accurate indoor localization information. Considering the problem of initial position determination, a hidden Markov model (HMM) is utilized to infer the user’s initial position. To provide an improved service for further applications, the landmarks are further assigned semantic descriptions by detecting the user’s activities. The experiments conducted in this study confirm that a high degree of accuracy for a user’s indoor location can be obtained. Furthermore, the semantic information of a user’s trajectories can be extracted, which is extremely useful for further research into indoor location applications.
The Optimization and Characterization of an RNA-Cleaving Fluorogenic DNAzyme Probe for MDA-MB-231 Cell Detection
Authors: Xue Pengcheng , He Shengnan , Mao Yu , Qu Long , Liu Feng , Tan Chunyan , Jiang Yuyang , Tan Ying
Published: March 2017

Breast cancer is one of the most frequently diagnosed cancers in females worldwide and lacks specific biomarkers for early detection. In a previous study, we obtained a selective RNA-cleaving Fluorogenic DNAzyme (RFD) probe against MDA-MB-231 cells, typical breast cancer cells, through the systematic evolution of ligands by exponential process (SELEX). To improve the performance of this probe for actual application, we carried out a series of optimization experiments on the pH value of a reaction buffer, the type and concentration of cofactor ions, and sequence minimization. The length of the active domain of the probe reduced to 25 nt from 40 nt after optimization, which was synthesized more easily and economically. The detection limit of the optimized assay system was 2000 MDA-MB-231 cells in 30 min, which is more sensitive than the previous one (almost 5000 cells). The DNAzyme probe was also capable of distinguishing MDA-MB-231 cell specifically from 3 normal cells and 10 other tumor cells. This probe with high sensitivity, selectivity, and economic efficiency enhances the feasibility for further clinical application in breast cancer diagnosis. Herein, we developed an optimization system to produce a general strategy to establish an easy-to-use DNAzyme-based assay for other targets.
Making Sense of Sustainability: A Practice Theories Approach to Buying Food
Authors: Brons Anke , Oosterveer Peter
Published: March 2017

In light of global climate change the relevance of sustainable food consumption is growing, yet access to it has not correspondingly developed. This paper addresses the issue of accessing sustainable food from a practice theories perspective. The case of students in Paris is examined by means of interviews and participant observation. Four indicators serve to structure the results, i.e., mode of recruitment, mode of engagement, degree of commitment, and bundles of practices. Based on this analysis, three types are constructed, each with distinct access issues. We conclude that access to sustainable food is not necessarily determined by financial means only, nor by individual attitudes, but should be analysed as embedded in the complex dynamics of multiple social practices. Building on these insights means that more attention for the actual practice of accessing sustainable food, the different elements, and bundles involved is needed when looking for ways to increase access to sustainable food.
Agricultural Productivity Growth and the Role of Capital in South Asia (1980–2013)
Authors: Anik Asif , Rahman Sanzidur , Sarker Jaba
Published: March 2017

The study assessed agricultural sustainability in South Asia (i.e., Bangladesh, Pakistan, India and Nepal) by computing multi-lateral multi-temporal Total Factor Productivity (TFP) indices and their six finer components (technical change, technical-, scale- and mix-efficiency changes, residual scale and residual mix-efficiency changes) and examined the role of capital in driving TFP growth covering a 34-year period (1980–2013). Results revealed that all countries sustained agricultural productivity growth at variable rates with Bangladesh experiencing highest rate estimated @1.05% p.a. followed by India (0.52%), Pakistan (0.38%) and Nepal (0.06% p.a.). There were little or no variation in technical and scale efficiency changes among the countries. However, residual scale efficiency increased @0.44% p.a. in Bangladesh, 0.12% p.a. in Pakistan, remained unchanged in India and declined −0.39% p.a. in Nepal. Similarly, mix efficiency increased @0.44% in Bangladesh, remained unchanged in India and declined @−0.12% p.a.in Pakistan and −0.39% p.a. in Nepal. The major drivers of agricultural TFP growth were the levels of natural, human and technology capital endowments whereas financial capital and crop diversification had opposite effects. Policy implications include land and tenurial reforms aimed at consolidating farm operation size and smooth operation of the land rental market to improve natural capital, investments in education to improve human capital and agricultural R&D to enhance technology capital in order to boost agricultural productivity growth in South Asia.
Changes of Fluctuating Asymmetry with Age in Human Fetuses and Young Infants
Authors: Dongen Stefan Van , Broek Claartje Ten , Bots Jessica , Galis Frietson
Published: March 2017

(1) Background: Developmental instability (DI), often measured by fluctuating asymmetry (FA), increases with stress in humans, yet little is known about how stress affects the changes of asymmetry with age. More specifically, it is unknown if fetuses experiencing a major congenital abnormality will express higher FA already during early development or only at a later age; (2) Methods: We combine two datasets to study associations between age and asymmetry in human fetuses and young infants. One population consists of fetuses from spontaneous abortions and early deceased infants where many experienced major congenital abnormalities, and a second from elicited abortions for social reasons; (3) Results: While the occurrence of major abnormalities did not seem to affect the way asymmetry decreased with age, differences between the two populations were observed; and (4) Conclusions: In one population where fetuses and young infants deceased of natural causes, asymmetry decreased rapidly until 20 weeks of age and then leveled off. Over the entire timespan (week 15–49), individuals with major congenital abnormalities showed higher FA, suggesting that developmental perturbations increase FA rapidly. In the second, more normal population with abortions solicited for social reasons, the decrease in asymmetry with age was less profound and not statistically significant, calling for further research toward understanding regional differences.
Virological Surveillance of Influenza A Subtypes Isolated in 2014 from Clinical Outbreaks in Canadian Swine
Authors: Grgić Helena , Gallant Jackie , Poljak Zvonimir
Published: March 2017

Influenza A viruses (IAVs) are respiratory pathogens associated with an acute respiratory disease that occurs year-round in swine production. It is currently one of the most important pathogens in swine populations, with the potential to infect other host species including humans. Ongoing research indicates that the three major subtypes of IAV—H1N1, H1N2, and H3N2—continue to expand in their genetic and antigenic diversity. In this study, we conducted a comprehensive genomic analysis of 16 IAVs isolated from different clinical outbreaks in Alberta, Manitoba, Ontario, and Saskatchewan in 2014. We also examined the genetic basis for probable antigenic differences among sequenced viruses. On the basis of phylogenetic analysis, all 13 Canadian H3N2 viruses belonged to cluster IV, eight H3N2 viruses were part of the IV-C cluster, and one virus belonged to the IV-B and one to the IV-D cluster. Based on standards used in this study, three H3N2 viruses could not be clearly classified into any currently established group within cluster IV (A to F). Three H1N2 viruses were part of the H1α cluster.
Complete and Incomplete Hepatitis B Virus Particles: Formation, Function, and Application
Authors: Hu Jianming , Liu Kuancheng
Published: March 2017

Hepatitis B virus (HBV) is a para-retrovirus or retroid virus that contains a double-stranded DNA genome and replicates this DNA via reverse transcription of a RNA pregenome. Viral reverse transcription takes place within a capsid upon packaging of the RNA and the viral reverse transcriptase. A major characteristic of HBV replication is the selection of capsids containing the double-stranded DNA, but not those containing the RNA or the single-stranded DNA replication intermediate, for envelopment during virion secretion. The complete HBV virion particles thus contain an outer envelope, studded with viral envelope proteins, that encloses the capsid, which, in turn, encapsidates the double-stranded DNA genome. Furthermore, HBV morphogenesis is characterized by the release of subviral particles that are several orders of magnitude more abundant than the complete virions. One class of subviral particles are the classical surface antigen particles (Australian antigen) that contain only the viral envelope proteins, whereas the more recently discovered genome-free (empty) virions contain both the envelope and capsid but no genome. In addition, recent evidence suggests that low levels of RNA-containing particles may be released, after all. We will summarize what is currently known about how the complete and incomplete HBV particles are assembled. We will discuss briefly the functions of the subviral particles, which remain largely unknown. Finally, we will explore the utility of the subviral particles, particularly, the potential of empty virions and putative RNA virions as diagnostic markers and the potential of empty virons as a vaccine candidate.
Genomic Insights into Cardiomyopathies: A Comparative Cross-Species Review
Authors: Simpson Siobhan , Rutland Paul , Rutland Catrin
Published: March 2017

In the global human population, the leading cause of non-communicable death is cardiovascular disease. It is predicted that by 2030, deaths attributable to cardiovascular disease will have risen to over 20 million per year. This review compares the cardiomyopathies in both human and non-human animals and identifies the genetic associations for each disorder in each species/taxonomic group. Despite differences between species, advances in human medicine can be gained by utilising animal models of cardiac disease; likewise, gains can be made in animal medicine from human genomic insights. Advances could include undertaking regular clinical checks in individuals susceptible to cardiomyopathy, genetic testing prior to breeding, and careful administration of breeding programmes (in non-human animals), further development of treatment regimes, and drugs and diagnostic techniques.
Size Distribution, Surface Coverage, Water, Carbon, and Metal Storage of Thermokarst Lakes in the Permafrost Zone of the Western Siberia Lowland
Authors: Polishchuk Yury , Bogdanov Alexander , Polishchuk Vladimir , Manasypov Rinat , Shirokova Liudmila , Kirpotin Sergey , Pokrovsky Oleg
Published: March 2017

Despite the importance of thermokarst (thaw) lakes of the subarctic zone in regulating greenhouse gas exchange with the atmosphere and the flux of metal pollutants and micro-nutrients to the ocean, the inventory of lake distribution and stock of solutes for the permafrost-affected zone are not available. We quantified the abundance of thermokarst lakes in the continuous, discontinuous, and sporadic permafrost zones of the western Siberian Lowland (WSL) using Landsat-8 scenes collected over the summers of 2013 and 2014. In a territory of 105 million ha, the total number of lakes >0.5 ha is 727,700, with a total surface area of 5.97 million ha, yielding an average lake coverage of 5.69% of the territory. Small lakes (0.5–1.0 ha) constitute about one third of the total number of lakes in the permafrost-bearing zone of WSL, yet their surface area does not exceed 2.9% of the total area of lakes in WSL. The latitudinal pattern of lake number and surface coverage follows the local topography and dominant landscape zones. The role of thermokarst lakes in dissolved organic carbon (DOC) and most trace element storage in the territory of WSL is non-negligible compared to that of rivers. The annual lake storage across the WSL of DOC, Cd, Pb, Cr, and Al constitutes 16%, 34%, 37%, 57%, and 73%, respectively, of their annual delivery by WSL rivers to the Arctic Ocean from the same territory. However, given that the concentrations of DOC and metals in the smallest lakes (<0.5 ha) are much higher than those in the medium and large lakes, the contribution of small lakes to the overall carbon and metal budget may be comparable to, or greater than, their contribution to the water storage. As such, observations at high spatial resolution (<0.5 ha) are needed to constrain the reservoirs and the mobility of carbon and metals in aquatic systems. To upscale the DOC and metal storage in lakes of the whole subarctic, the remote sensing should be coupled with hydrochemical measurements in aquatic systems of boreal plains.
Assessment of Three Long-Term Gridded Climate Products for Hydro-Climatic Simulations in Tropical River Basins
Authors: Tan Mou Leong , Gassman Philip W. , Cracknell Arthur P.
Published: March 2017

Gridded climate products (GCPs) provide a potential source for representing weather in remote, poor quality or short-term observation regions. The accuracy of three long-term GCPs (Asian Precipitation—Highly-Resolved Observational Data Integration towards Evaluation of Water Resources: APHRODITE, Precipitation Estimation from Remotely Sensed Information using Artificial Neural Network-Climate Data Record: PERSIANN-CDR and National Centers for Environmental Prediction Climate Forecast System Reanalysis: NCEP-CFSR) was analyzed for the Kelantan River Basin (KRB) and Johor River Basin (JRB) in Malaysia from 1983 to 2007. Then, these GCPs were used as inputs into calibrated Soil and Water Assessment Tool (SWAT) models, to assess their capability in simulating streamflow. The results show that the APHRODITE data performed the best in precipitation estimation, followed by the PERSIANN-CDR and NCEP-CFSR datasets. The NCEP-CFSR daily maximum temperature data exhibited a better correlation than the minimum temperature data. For streamflow simulations, the APHRODITE data resulted in strong results for both basins, while the NCEP-CFSR data showed unsatisfactory performance. In contrast, the PERSIANN-CDR data showed acceptable representation of observed streamflow in the KRB, but failed to track the JRB observed streamflow. The combination of the APHRODITE precipitation and NCEP-CFSR temperature data resulted in accurate streamflow simulations. The APHRODITE and PERSIANN-CDR data often underestimated the extreme precipitation and streamflow, while the NCEP-CFSR data produced dramatic overestimations. Therefore, a direct application of NCEP-CFSR data should be avoided in this region. We recommend the use of APHRODITE precipitation and NCEP-CFSR temperature data in modeling of Malaysian water resources.
De la clandestinité de l’amour pour les familles à l’intérieur du dispositif de protection de l’enfance au Québec
Authors: Lacharité Carl
Published: March 2017

L’article vise à montrer que le dispositif de protection de l’enfance au Québec constitue un environnement institutionnel où le sentiment amoureux n’a que peu d’écho, en particulier en ce qui a trait à un phénomène que des professionnelles nomment « l’amour pour les familles ». L’un des obstacles relève de la représentation dominante de l’amour en Occident et de la difficulté à distinguer entre différentes catégories du sentiment amoureux. Un modèle alternatif de l’amour y est présenté. Il permet de rendre compte des expressions « clandestines » de l’amour pour les familles chez les professionnelles.
Aimer son travail : 13 novembre 2015 dans un hôpital parisien
Authors: Gomez Jean-François
Published: March 2017

À partir du récit de la nuit du 13 novembre 2015 à l’hôpital Saint-Antoine à Paris, proche du Bataclan, l’auteur étudie le comportement du personnel hospitalier, pris dans la tourmente d’événements exceptionnels. La gravité de la situation va les obliger à s’adapter très rapidement ; les principes de hiérarchie et d’organisation se verront radicalement modifiés. L’auteur en tire des réflexions actuelles sur les orientations managériales à l’hôpital, puis par extension sur les évolutions du travail social, alimentées par les travaux récents de deux sociologues. Pour l’idéologie managériale, la grande inconnue est précisément la « merveille » qui s’est produite à Saint-Antoine et qui a pu enfin se libérer : la capacité des professionnels d’aimer leur travail et de s’y investir en pleine capacité.
La politique européenne de transparence (2005-2016) : de la contestation à la consécration du lobbying
Authors: Robert Cécile
Published: March 2017

Cet article s’attache à comprendre comment une politique promue au nom d’un meilleur contrôle des pratiques de représentation d’intérêts, et parfois d’une vision très critique de ces dernières, a contribué à en consacrer l’usage, y compris auprès de ses plus virulents détracteurs. La transparence apparaît en effet comme une « solution » investie par des acteurs porteurs de représentations très différentes du « problème du lobbying  ». Tant chez les acteurs institutionnels que parmi les ONG mobilisées et pour des raisons variées, c’est néanmoins progressivement une conception moralisante, l’envisageant comme une question d’éthique qui l’emporte, au détriment d’une lecture plus politique, qui l’analysait comme l’un des vecteurs de la domination des intérêts privés sur le processus décisionnel européen. L’analyse de la coproduction de cette politique par ses promoteurs publics et privés au cours de la dernière décennie permet ainsi conjointement d’interroger leurs capacités différentielles à orienter l’action publique, et notamment ce qu’implique le fait que le système politique européen impose à ses opposants la forme de leurs revendications.
Education and Human Capital
Authors: Papadopoulou Olga
Published: March 2017

In European Union, human capital along with its basic expression education has been placed high on the policy agenda. This chapter aims to analyze the human capital in Greece, in order to provide an integrated overview on how well Greece is operating its human capital and education targets, under the terms of Europe 2020 strategy. Consequently, the achievement of the relevant ethnic targets is vital, for having a “smart, sustainable, inclusive growth” in Greece.
Education and Economic Growth
Authors: Demosthenous Aliki
Published: March 2017

This chapter aims to analyze the framework of education and to measure the efficiency of education by means of the Data Envelopment Analysis method. The Data Envelopment Analysis is a nonparametric method used in operational research and in economics for estimating production frontiers. It can be used to measure empirically the efficiency of decision making units (DMUs). Measuring efficiency in education is of high priority as substantial investments in education are made by the European Union contributing thus to the accumulation and growth of human capital. Education, training and lifelong learning, are important “levers” that contribute towards the economic growth and the enhancement of competitiveness. The skills acquired by the employees through training and lifelong learning raise the corporate competitiveness by achieving economic growth and also assist in meeting their corporate and individual social responsibilities. The educational process at all levels is not just a simple truth that is continuously verified. It is the basis upon which Europe is based on. It is a collective investment of high priority which contributes to the macro and micro-economic objectives of the EU economies. It contributes to the harmonious social growth of the EU countries and the formation of peoples' intellectual culture.
Unemployed
Authors: Michailidis Maria P. , Michailidis Evie , Ganztias George K.
Published: March 2017

The current paper discusses findings from an exploratory study concerning the type, frequency of use and the impact of social networking sites on unemployed. The study's objectives were to assess participants' under training: usage of social networking sites, and the degree to which these helped increase their opportunities for employability, educational enhancement, and contributed to their psychological uplift and social support. The paper contributed to the research on social networking and the education of the unemployed in a country where similar research is sporadic.
Legal Definition of the Concept of Private Productive Investment
Authors: Delitheou Vasiliki
Published: March 2017

This chapter attempts to analyse the concept of private investment through the regulations and legislations paying emphasis to the Greek legal system. It also attempts to analyse the whole framework, through an inter-comparison study, in order to reach some safe conclusions regarding this issue.
Changes in the Political Culture of Italian Younger Politicians
Authors: Saccà Flaminia
Published: March 2017

In the last decade, Italy has gone through some deep changes in the political sphere. The fall of the Berlin Wall had forced political parties from opposite sides to re-organize themselves: their targets, ideologies and projects. At the same time, these historical events have been shortly followed by a major national bribe scandal that invested the main political leaders who had governed the Country for half a century. As a result, the last turn of the past Millennium has left a strongly politicized Country with no acknowledged leaders, no clear ideologies, no traditional, recognizable parties. It is in those years that Berlusconi's new venture gained votes and success. The fracture between political organizations, leaders and citizens though, became unhealable. The younger generations seemed to be the ones who suffered the most from political apathy or, worse, distrust. So we wanted to investigate who were the young politicians who, in these times of crises, had chosen politics as an important part of their lives. We have carried out two different surveys in different years and we found that political parties were changing deeply and radically. That their role in the political socialization of young political actors had become very thin. That candidates began to be chosen amongst the affluent few or, at least, amongst those whose personal fame and social/professional/family network would guarantee their party at least a dowry of votes that could make the difference in times of elections. But this method would not guarantee cohesion nor government stability.
Social Impact of the Fiscal Crisis Upon the Livelihood Conditions of the Children of Greece
Authors: Tsobanoglou George O. , Giannopoulou Ioanna
Published: March 2017

This chapter focuses on the effects of the fiscal crisis, which is assumed as a stressor or traumatic event, on children's emotional, physical and developmental well-being. Emphasis is placed on how individual, family and community risk factors and resources might be critical in increasing children's psychological vulnerability in times of such acute crisis. The key issues related to the provision of mental health services in times of increased pressure put upon them are discussed.
Mechanisms for the Formation of Tourism Organization Models in Greece Through a Comparative Analysis of Ten Greek Destinations' Development
Authors: Efthymia Sarantakou
Published: March 2017

The scope of the chapter is to research and interpret how the organization models of tourism development have advanced in Greece at traditional, mainly coastal, tourist destinations. Using the notion of organization models, the chapter examines the size and category of tourism facilities and a series of qualitative characteristics, as well as the spatial “behavior” of the phenomenon.
Laterally Inhomogeneous Barrier Height Analysis for Thermally Annealed CuNiTi/p-InP Contacts
Authors: Abay Bahattin
Published: March 2017

The fabrication of thermally stable Schottky contacts with high barrier height (BH) to InP is one of the main challenges for InP-based device technology. CuNiTi/p-InP Schottky barrier diodes (SBDs) (25 dots) on p-InP substrate were fabricated by conventional vacuum deposition. Characteristic parameters such as BH and ideality factor (n) of as-deposited and annealed CuNiTi/p-InP diodes have been computed by thermionic emission (TE) theory from the forward-bias current-voltage (I-V) data, at room temperature and in dark. The value of BH and n varies from 0.452 to 0.631 eV and 1.172 to 2.815, respectively for the as-deposited SBDs. The results showed that characteristic parameters of CuNiTi/p-InP structures differ from one device to another even though they were identically prepared. Hence, to overcome these problems post thermal annealing was implemented since the annealing process can improve the interfacial quality as well as can induce a recrystallization of the gate metals. BH values for CuNiTi/p-InP SBDs have also varied from 0.765 to 0.804 eV, and ideality factor n from 1.161 to 1.253 after annealing at 500 °C for two minutes. As a result of the thermal annealing, it has been seen that the BH values of the annealed SBDs are larger than those of the as-deposited ones. A statistical study on the diode parameters has been made. The experimental BH and ideality factor distributions were fitted by a Gaussian distribution (GD) function. Lateral homogeneous BH (φhom.) values of 0.628 eV and 0.886 eV for the as-deposited and annealed CuNiTi/p-InP SBDs has been obtained from the φeff.-n plots by using Tung’s lateral inhomogeneity approach. An increment of 0.258 eV in the BH for the 500 °C annealing devices with respect to that of the as-deposited ones has been ascribed to the formation of the positively charged interface defects that electrically actives in the metal-semiconductor (MS) interface.
Effects of Various Pretreatment Variables on Hydrolysis of Lignocellulose to Produce Sugar in Bioethanol Production
Authors: Mulyaningtyas Akida , Kayati Fitri Nur , Syamsiah Siti , Sarto Sarto , Sediawan Wahyudi Budi
Published: March 2017

This research intends to explore the effect of pretreatment on lignoselulose to be used as raw material for bioethanol production. Pretreatment prepares lignocellulose compounds to be more easily hydrolyzed. Several variables were tested on oil palm empty fruit bunch (OPEFB) i.e. temperature, NaOH concentration, and particle size. According to the method of size reduction, there are two types of pretreatment which were milling and cutting. The first pretreatment type consisted of milling and screening resulting -+10-30, -30+40, -40+80, and-80 mesh. Each size fractions were then soaked in water at 90 °C for 2 hours. Meanwhile the second type consisted of cutting to 1 cm length followed by soaking in NaOH solutions for 2 hours. The operating temperatures at the second type were varied at 90 °C, 120 °C, 150 °C, 170 °C while the NaOH concentrations applied were 0%, 0.5%, 1%, 2%, 5%, 10%.The pretreated OPEFB was then hydrolyzed using cellulase produced by Aspergillusniger grown in situ. It was revealed that the relatively good pretreatment condition was milling to-80 mesh followed by soaking in hot water at 90 °C. It gave the highest produced sugar concentration at 15 g/L while other type resulted only 5.8 g/L.
Microwave-Irradiation Induced Fast Simultaneous Extraction of Methoxylated and Hydroxylated Phenolic Compounds from Orthosiphon stamineus Leaves
Authors: Pang Sook Fun , Lau Mei Zhu , Yusoff Mashitah Mohd , Gimbun Jolius
Published: March 2017

A combined effect of microwave irradiation and solvent types on the phenolic compounds extraction from Orthosiphon stamineus leaves was studied. The effect of as extraction time, the microwave irradiation power and solid to solvent ratio on the extraction yield was studied. Aqueous solvent provides a broader range of polarity than the pure solvent, and hence enabled a simultaneous extraction of both methoxylated and hydroxylated phenolic compounds. It was found that the extraction time of 2 minutes, microwave irradiation power at 300W and 20:1 solvent to solid ratio yielded highest simultaneous extraction of polyphenols (i.e. rosmarinic acid 32.45 mg RA/g DW, sinensetin 261.15 μg Sin/g DW and eupatorin 2.27 mg Eup/g DW). Result from this work may serve as a useful guide to obtain higher yield of polyphenols from O. stamineus.
Hardness Removal from Water by Modified Starch
Authors: Racho Patcharin , Namseethan Kusuma
Published: March 2017

This is a preliminary study for hardness removal via modified starch combined with an ultrafiltration process that provides on high effluence quality and low cost, footprint and environmental impact treatment. This studied on potential of chemisorption process using modified starch as absorbents for hardness removal. Four modified tapioca starches were selected for evaluation that includes of oxidize starch, di-starch phosphate, hydroxyphophyl starch and phosphate monoester as well as non-modified tapioca starch too. Phosphate monoester starch achieved the highest efficiency about 98.2% of hardness removal within the adsorption capacity about 18 mg-hardness removed/g-starch. The modified starch had capable to reduced total hardness from 350.5 mg/L as CaCO3 to 6.3 mg/L as CaCO3 from water. However, the modified starch is an organic matter its can be contaminates in water. Then, a coagulation-flocculation processes were applied for starch colloidal destabilization and flocs by aluminum chloride (PAC) and cationic polymer for starch separation. After that process, turbidity was less than 1 NTU in the effluents. However, the total dissolved solids were increased that may be cause of some starch was solutes. These should be having a future treatment for particulate removal and cutoff the soluble starch in water likes an ultrafiltration process.
Enzymatic Activity of Immobilized Carbonic Anhydrase onto Amberlite XAD7
Authors: Hamzah Fazlena , Abdullah Siti Nadia , Mohd Rafidi Siti Noor Hazirah
Published: March 2017

Carbon capture by using carbonic anhydrase (CA) enzyme has become an alternative and environmental friendly approach in carbon sequestration technology. Among various form of CA, immobilized CA onto the support materials offer better behaviour of enzyme including enhance enzyme stability, increase biocatalytic activity and improved enzyme reusability. These factors are important in carbon sequestration in order to reduce the operation cost and achieve optimum CO2 utilization. Thus, behaviour of the CA immobilized onto the solid support is important in order to determine its activity towards CO2 capture. In this study, different initial concentration of CA immobilized onto amberlite XAD7 was investigated for the optimum CO2 sequestration through protein analysis and enzyme activity towards p-NPA substrate. The CA initial concentration was varied from 0.32 to 1.87 mg/ml while other parameters were kept constant where temperature at 25°C, speed shaking at 100 rpm, pH at 8.0 and support dosage at 0.5g. The CA initial concentration at 0.32 mg/ml gave the highest percentage of immobilized enzyme (99%). While, the highest enzyme activity towards its substrate obtained was 1.58mmol/min using 99% CA attached to amberlite XAD7.
Optimization of Ultrasonic-Assisted Extraction of Polyphenolic and Flavonoids from Labisia pumila
Authors: Sandanasamy Jessinta , Yusoff Mashitah Mohd , Gimbun Jolius
Published: March 2017

This work presents an optimization study of polyphenol extraction from L. pumila with aid of sonication. The polyphenol content was evaluated using Singleton’s method and aluminium chloride colorimetric assay. The two level factorial design [2LF] was used to screen the significance of the extraction parameters. The results proposed that the polyphenols extraction are mainly affected by the total solid ratio [TSR] and residence time. The highest flavonoid content of 31.79 mg QE/ g DW and phenolic content of 19.65 mg GA/g DW was obtained from 80% and 10% aqueous ethanol [EtOH], respectively via 2LF design. Three most important parameters [TSR, residence time and amplitude] were then further optimized thru central composite design. The highest simultaneous flavonoid [21.77 mg QE/ g DW] and phenolic [21.86 mg GA/g DW] extraction yield were attained from the probe sonicator extraction with desirability of 0.998 at 10% aqueous EtOH with TSR 0.01, residence time of 13 min and amplitude of 55%.
Swelling and Crosslinked Formaldehyde Chitosan as Adsorbent for Metal Ion Cu (II)
Authors: Hastuti Budi , Santrinitas Yulia
Published: March 2017

Research about comparison of chitosan modified by swelling and formaldehyde crosslinked in adsorption of metal ion Cu (II) on variation of pH solution and concentration of chitosan has been done. The purpose of this research are to: 1) Determine the degree of deacetylation of chitosan and modified chitosan by swelling and formaldehyde crosslinked. 2) Determine the adsorption capacity of chitosan modified by swelling and formaldehyde crosslinked in adsorption of Cu (II) metal ion. The result of the research showed that: 1) The degree of deacetylation on optimum conditions of each chitosan was 70,3% for technical chitosan; 89,7% for modified chitosan by swelling and 82,5% for chitosan formaldehyde crosslinked. 2) The adsorption capacity in the optimum condition of chitosan modified by swelling and crosslink for the adsorption metal ion Cu (II) were 77,42%, and 75,16%.
Addition of Mo Zn Fe and Ag into HZSM-5 and NaZSM-5 Catalysts
Authors: Pintavirooj Pannaporn , Jitto Ponlakit , Chaimoon Nida
Published: March 2017

This research objective was to study a synthesis of metal ZSM-5 catalyst by adding the metals into the HZSM-5 and NaZSM5. Metals used were silver (Ag), Zinc (Zn), Iron (Fe), and Molybdenum (Mo) by allegorizing with the calcined and without calcined catalyst. The catalyst structure was showed by Scanning Electron Microscopy (SEM). Each catalyst was determined in terms of element quantity by the Energy Dispersive X-Ray Fluorescence Spectrometer. The results of this research were showed that every type of metal can exchange on Hydrogen or Sodium of HZSM-5 and NaZSM-5, respectively. Molybdenum (Mo), Zinc (Zn), Iron (Fe) and Silver (Ag) were added into HZSM-5, then the ratio of Si:Al:Metals were 9.24:0.49:1, 48.21:2.66:1, 85.73:4.55:1 and 17.53:0.93:1, respectively. While the Mo, Zn, Fe, and Ag were added into NaZSM-5 to be a complex catalyst. The ratios were 10.11:0.53:1, 43.93:2.44:1, 93.19:5.35:1 and 11.50:0.65:1, respectively. The conclusions indicated that Mo was the best metal that can be added to ZSM-5, while Fe was the less. NaZSM-5 was more efficiency for adding each metal than HZSM-5.
Effects of Alkali and Thermal Treatment on the Ti6Al4V towards Apatite Deposition in Dulbecco’s Phosphate Buffered Saline (DPBS) Solution
Authors: Hamzah Fazlena , Liansim Rachel Michael S. , Hanib Nurul Hazwani
Published: March 2017

A high biocompatibility apatite coated titanium (Ti) could be achieved by biomimetic method. The method is beneficial in surface modification by lowering the processing cost and flexibility. However, the bond between apatite and titanium implant is weak. The structure and composition of apatite formed is different from the apatite in bone. The aim of this research was to investigate the effects of heat and alkali treatment on the physical and chemical properties of Ti6Al4V surfaces and to observe the formation of apatite in Dulbecco’s Phosphate Buffered Saline with CaCl2 and MgCl2 (DPBS) solution on the treated Ti6Al4V for medical implants. Ti discs were surface modified by alkali etching using 5M NaOH at temperature 60°C for 24 hours. A stable mechanical structure of sodium titanate layer formed on alkali-treated is consolidating by heat treated at 500°C and 600 °C. Treated samples were then incubated at 37°C into DPBS solution for 3 days. The morphology structure, phase changes and chemical composition were characterized by using Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Powder Diffraction (XRD). The results shows that apatite coating in globular shape, a group of flakes was found on the samples’ surfaces that had been pre-treated with 5M NaOH at temperature 60°C without thermal treatment and thermal treated at 500°C.
Preparation and Dye Removal Properties of Hyperbranched Polymeric Ionic Liquid/Poly(Vinylidene Fluoride) Composite Films
Authors: Song Wen Qi , Liu Yu Yang , Hou Yu , Wang Yan
Published: March 2017

Based on the selective adsorption property of the imidazolium-type hyperbranched polymeric ionic liquid (hb-PIm+PF6-) towards anionic dyes, it was incorporated into poly(vinylidene fluoride) (PVDF) matrix to modify PVDF film. The composite hb-PIm+PF6-/PVDF films were prepared via non-solvent-induced phase inversion method. The obtained composite films were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle goniometry. Using bromophenol blue (BPB, an acidic dye) as the model molecule, the dynamic and static adsorption properties of the hb-PIm+PF6-/PVDF films were investigated, respectively. It is significant that the hb-PIm+PF6-/PVDF composite films could efficiently remove BPB from water under dynamic condition.
Tensile Properties of Woven Carbon/Kevlar Reinforced Epoxy Hybrid Composite
Authors: HASHIM NURAIN , Abdul Majid Dayang Laila , Zahari Rizal , Yidris Noorfaizal
Published: March 2017

Carbon fibres and Kevlar fibres are among the commonly used fibres in the composite industry. As carbon fibres usually known for its superior strength, its low impact resistance limited its application in the industry. However, further research found that combining the high strength fibres with more ductile fibres like Kevlar could improve the material’s impact resistance. This hybrid effect was also found to be most effective by using intra-ply woven hybrid fibres in the composite. In this work, hybrid composite material was fabricated by using woven carbon-Kevlar cloths with epoxy matrix and the mechanical properties are determined at 0 ̊, 45 ̊ and 90 ̊. The hybrid composite material was found to have highest tensile strength at 0 ̊ (carbon) direction. As the material’s strength and tensile behaviour are different at every fibre types, the selection of fibre direction of the woven cloth in loading is an important criteria in any applications.
Microscopic Methods for Characterization of Selected Surface Properties of Biodegradable, Nanofibrous Tissue Engineering Scaffolds
Authors: Chlanda Adrian , Kijeńska Ewa , Święszkowski Wojciech
Published: March 2017

Biodegradable polymeric fibers with nanoand submicron diameters, produced by electrospinning can be used as scaffolds in tissue engineering. It is necessary to characterize their mechanical properties especially at the nanoscale. The Force Spectroscopy is suitable atomic force microscopy mode, which allows to probe mechanical properties of the material, such as: reduced Young's modulus, deformation, adhesion, and dissipation. If combined with standard operating mode: contact or semicontact, it will also provide advanced topographical analysis. In this paper we are presenting results of Force Spectroscopy characterization of two kinds of electrospun fibers: polycaprolactone and polycaprolactone with hydroxyapatite addition. The average calculated from Johnson-Kendall-Roberts theory Young's modulus was 4 ± 1 MPa for pure polymer mesh and 20 ± 3 MPa for composite mesh.
Hydrogen Bonds-Enhanced Organoclay-Free Oil Based Drilling Fluid System
Authors: Huang Xian Bin , Jiang Guan Cheng
Published: March 2017

Conventional oil based drilling fluids or muds (OBMs) using organophilic clay as viscosifier and rheological control agent cannot carry drill cuttings and suspend weighting materials effectively in oil well drilling process. It also causes excessive viscosity of drilling fluids, which lowers the rate of penetration. For the sake of solving these problems, in this study, hydrogen bonds-enhanced organoclay-free oil based drilling fluid was proposed. Firstly key additives (emulsifier, filter reducer) for OBMs with highly electronegative groups that might form hydrogen bonds were synthesized. In addition, a hydrogen bonding linker was synthesized and used to connect other additives to form a hydrogen bonding network in OBMs. The properties of drilling fluids were characterized by rheological measurements, static filtration experiments and plugging experiments. Experimental results show that, compared with the conventional OBM, the hydrogen bonds-enhanced organoclay-free OBMs substantially increased yield point (YP) and gel strengths, reduced filtration loss and exhibited a better plugging ability on high-permeability sand cores. Besides, a higher stability was also observed.
Interfacial Tension Measurement of Light Oil from Thailand to Enhance Oil Recovery for Surfactant Flooding Application
Authors: Chuaicham Chitipat , Maneeintr Kreangkrai
Published: March 2017

To enhance oil recovery, surfactant flooding is one of the techniques used to reduce the interfacial tension (IFT) between displacing and displaced phases in order to maximize productivity. Due to high salinity of crude oil in the North of Thailand, surfactant flooding is a suitable choice to perform enhanced oil recovery. The objective of this work is to measure the IFT and observe the effects of parameters such as pressure, temperature, concentration and salinity on IFT reduction. In this study, sodium dodecylbenzenesulfonate is used as surfactant to reduce IFT. The results show that the major factor affecting reduction of IFT is surfactant concentration accounting for 98.1%. IFT reduces with the increase of salinity up to 86.3% and up to 9.6% for temperature. However, pressure has less effect on IFT reduction. The results of this work can apply to increase oil production in the oilfield in the North of Thailand.
Molecular Dynamics Simulation Study of Lecithin Inhibiting Hydrate-Dissociation
Authors: Wang Le , Jiang Guan Cheng , Lin Xin , Zhang Xian Min , Jiang Qi Hui
Published: March 2017

Molecular dynamics simulations are used to study the dissociation inhibiting mechanism of lecithin for structure I hydrates. Adsorption characteristics of lecithin and PVP (poly (N-vinylpyrrolidine)) on the hydrate surfaces were performed in the NVT ensemble at temperatures of 277K and the hydrate dissociation process were simulated in the NPT ensemble at same temperature. The results show that hydrate surfaces with lecithin is more stable than the ones with PVP for the lower potential energy. The conformation of lecithin changes constantly after the balanced state is reached while the PVP molecular dose not. Lecithin molecule has interaction with lecithin nearby and hydrocarbon-chains of lecithin molecules will form a network to prevent the diffusion of water and methane molecules, which will narrow the available space for hydrate methane and water movement. Compared with PVP-hydrate simulation, analysis results (snapshots and mass density profile) of the dissociation simulations show that lecithin-hydrate dissociates more slowly.
Influence of Annealing Temperature on the Properties of SnS Thin Films Prepared by Vacuum Thermal Evaporation
Authors: Wongcharoen Ngamnit , Gaewdang Thitinai
Published: March 2017

SnS thin films were deposited by thermal evaporation in vacuum on glass slide substrate. The as-deposited films were thermally annealed in a controlled N2 atmosphere with annealing temperature in the range 100-500°C for 30 min. XRD, AFM, UV-VIS transmittance, FTIR and Hall effect measurements were used for characterization the as-deposited and annealed films. Based on the XRD patterns, the as-deposited and annealed films were indentified as the orthrombic structure. The band gap was found to increase from 1.15 to 1.42 eV when the annealing temperature increased from 100 to 500°C. The lowest resistivity and highest carrier concentration values were observed to be 12.95 Ω.cm and 1.98×1016 cm-3 on the films annealed at 100 and 200°C, respectively.
Hot Deformation Behaviour and Microstructural Evaluation of Zr-1Nb Alloy
Authors: Saxena Kuldeep Kumar , Pancholi Vivek , Chaudhari Gajanan Prabhakar , Srivastava Dinesh , Dey Gautam Kumar , Jha Sanjay K. , Saibaba N.
Published: March 2017

In nuclear water reactors, zirconium alloys are extensively used as fuel cladding material and in other structural applications. Uniaxial hot compression tests were performed to understand the deformation behavior of Zr-1Nb alloy. Therefore, hot compression tests were performed in the temperature range of 700-1050°C, which envelopes α-phase, (α+β) phase, and β-phase. True stress-strain curves, processing maps, microstructural observation and kinetic analysis were used to discuss the deformation behavior of Zr-1Nb alloy. Deformation at a strain rate of 10-2 s-1 reveals softening at lower temperatures and steady state behavior at higher temperatures. Processing map also reveals domain of high efficiency at 10-2 s-1 strain rate for a wide range of deformation temperatures. The flow softening and high power dissipation efficiency predicts dynamic recrystallization or dynamic recovery during the hot deformation of studied alloy.