bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of Chlorophyll-a Concentration and the Trophic State of the Barra Bonita Hydroelectric Reservoir Using OLI/Landsat-8 Images
Authors: Watanabe Fernanda , Alcântara Enner , Rodrigues Thanan , Imai Nilton , Barbosa Cláudio , Rotta Luiz
Published: August 2015

Reservoirs are artificial environments built by humans, and the impacts of these environments are not completely known. Retention time and high nutrient availability in the water increases the eutrophic level. Eutrophication is directly correlated to primary productivity by phytoplankton. These organisms have an important role in the environment. However, high concentrations of determined species can lead to public health problems. Species of cyanobacteria produce toxins that in determined concentrations can cause serious diseases in the liver and nervous system, which could lead to death. Phytoplankton has photoactive pigments that can be used to identify these toxins. Thus, remote sensing data is a viable alternative for mapping these pigments, and consequently, the trophic. Chlorophyll-a (Chl-a) is present in all phytoplankton species. Therefore, the aim of this work was to evaluate the performance of images of the sensor Operational Land Imager (OLI) onboard the Landsat-8 satellite in determining Chl-a concentrations and estimating the trophic level in a tropical reservoir. Empirical models were fitted using data from two field surveys conducted in May and October 2014 (Austral Autumn and Austral Spring, respectively). Models were applied in a temporal series of OLI images from May 2013 to October 2014. The estimated Chl-a concentration was used to classify the trophic level from a trophic state index that adopted the concentration of this pigment-like parameter. The models of Chl-a concentration showed reasonable results, but their performance was likely impaired by the atmospheric correction. Consequently, the trophic level classification also did not obtain better results.
Locations that Support Social Activity Participation of the Aging Population
Authors: Berg Pauline , Kemperman Astrid , De Kleijn Boy , Borgers Aloys
Published: August 2015

Social activities are an important aspect of health and quality of life of the aging population. They are key elements in the prevention of loneliness. In order to create living environments that stimulate older adults to engage in social activities, more insight is needed in the social activity patterns of the aging population. This study therefore analyzes the heterogeneity in older adults’ preferences for different social activity location types and the relationship between these preferences and personal and mobility characteristics. This is done using a latent class multinomial logit model based on two-day diary data collected in 2014 in Noord-Limburg in the Netherlands among 213 respondents aged 65 or over. The results show that three latent classes can be identified among the respondents who recorded social activities in the diary: a group that mainly socializes at home, a group that mainly socializes at a community center and a group that is more likely to socialize at public ‘third’ places. The respondents who did not record any interactions during the two days, are considered as a separate segment. Relationships between segment membership and personal and mobility characteristics were tested using cross-tabulations with chi-square tests and analyses of variance. The results suggest that both personal and mobility characteristics play an important role in social activity patterns of older adults.
Extraction of Peptidoglycan from L. paracasei subp. Paracasei X12 and Its Preliminary Mechanisms of Inducing Immunogenic Cell Death in HT-29 Cells
Authors: Tian Pei-Jun , Li Bao-Long , Shan Yu-Juan , Zhang Jin-Na , Chen Jing-Yu , Yu Min , Zhang Lan-Wei
Published: August 2015

L. paracasei subp. paracasei X12 was previously isolated from a Chinese traditional fermented cheese with anticancer activities and probiotic potential. Herein, the integral peptidoglycan (X12-PG) was extracted by a modified trichloroacetic acid (TCA) method. X12-PG contained the four representative amino acids Asp, Glu, Ala and Lys, and displayed the similar lysozyme sensitivity, UV-visible scanning spectrum and molecular weight as the peptidoglycan standard. X12-PG could induce the production of apoptotic bodies observed by transmission electron microscopy (TEM). X12-PG could significantly induced the translocation of calreticulin (CRT) and the release of high mobility group box 1 protein (HMGB1), the two notable hallmarks of immunogenic cell death (ICD), with the endoplastic reticulum (ER) damaged and subsequently intracellular [Ca2+] elevated. Our findings implied that X12-PG could induce the ICD of HT-29 cells through targeting at the ER. The present results may enlighten the prospect of probiotics in the prevention of colon cancer.
Highlight: Mitochondrial Mechanisms in Septic Cardiomyopathy
Authors: International Journal of Molecular Sciences Editorial Office
Published: August 2015

The paper “Mitochondrial Mechanisms in Septic Cardiomyopathy” [1], published in the current issue offers an excellent overview for readers of the International Journal of Molecular Sciences.[...]
Changes in Sagittal Plane Kinematics and Kinetics after Distal Release of Medial Hamstrings in Cerebral Palsy
Authors: Eid Mohamed , To Michael , Chow Wang
Published: August 2015

The purpose of this study is to analyze the effect of distal release of the medial hamstrings on the gait of patients who had spastic cerebral palsy. Twenty-two patients had preoperative and postoperative gait analysis. Standard parameters, such as cadence, velocity, and stride length, were evaluated, as were sagittal plane motion graphs of the pelvis, hip, knee, and ankle, in addition to sagittal plane kinetic analysis. Extension of the knee in stance phase significantly improved postoperatively (p < 0.002), and the improvement was accompanied by a proportional decrease in knee flexion during swing with minimal net gain in the arc of knee motion. Knee range of motion could be improved more by concomitant rectus transfer in selected patients. The statistically significant increase in anterior pelvic tilt (p < 0.002) has been a main concern. There was no significant change in the hip extensor moments or power generation during stance. Increased knee extension during stance after distal release of medial hamstrings is the kinematic gain that improved the gait pattern in cerebral palsy patients. The authors recommend a concomitant rectus transfer to help improve the knee range of motion in patients with rectus over-firing during swing, hence avoiding a stiff knee gait.
Early-Age Strength of Ultra-High Performance Concrete in Various Curing Conditions
Authors: Park Jong-Sup , Kim Young , Cho Jeong-Rae , Jeon Se-Jin
Published: August 2015

The strength of Ultra-High Performance Concrete (UHPC) can be sensitively affected by the curing method used. However, in contrast to the precast plant production of UHPC where a standard high-temperature steam curing is available, an optimum curing condition is rarely realized with cast-in-place UHPC. Therefore, the trend of the compressive strength development of UHPC was experimentally investigated in this study, with a focus on early-age strength by assuming the various curing conditions anticipated on site. Concrete specimens were cured under different conditions with variables including curing temperature, delay time before the initiation of curing, duration of curing, and moisture condition. Several conditions for curing are proposed that are required when the cast-in-place UHPC should gain a specified strength at an early age. It is expected that the practical use of UHPC on construction sites can be expedited through this study.
Structure-Activity Relationships of the Antitumor C5-Curcuminoid GO-Y030
Authors: Kohyama Aki , Yamakoshi Hiroyuki , Hongo Shoko , Kanoh Naoki , Shibata Hiroyuki , Iwabuchi Yoshiharu
Published: August 2015

1,5-Bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadiene-3-one (2) was isolated from Curcuma domestica as a curcumin (1)-related compound, which we named C5-curcumin. Intrigued by the potent antitumor activity of C5-curcumin (2)-related 1,5-bisaryl-1,4-pentadiene-3-ones [bis(arylmethylidene)acetones, termed C5-curcuminoids], we previously conducted a structure–activity relationship study of C5-curcuminoids and showed that highly active GO-Y030 [1,5-bis(3,5-bis(methoxymethoxy)phenyl)-1,4-pentadiene-3-one (4)] is the most promising antitumor compound. In this study, a panel of C5-curcuminoids based on GO-Y030, consisting of 30 new and 10 known compounds, was synthesized to elucidate in detail which moiety of GO-Y030 is significant for antitumor activity. The results confirmed that both the cross-conjugated dienone moiety and the 3,5-bis(methoxymethoxy) substituent are important for the antitumor activity.
The Potential Use of Natural and Structural Analogues of Antimicrobial Peptides in the Fight against Neglected Tropical Diseases
Authors: Lewies Angélique , Wentzel Johannes , Jacobs Garmi , Du Plessis Lissinda
Published: August 2015

Recently, research into the development of new antimicrobial agents has been driven by the increase in resistance to traditional antibiotics and Emerging Infectious Diseases. Antimicrobial peptides (AMPs) are promising candidates as alternatives to current antibiotics in the treatment and prevention of microbial infections. AMPs are produced by all known living species, displaying direct antimicrobial killing activity and playing an important role in innate immunity. To date, more than 2000 AMPs have been discovered and many of these exhibit broad-spectrum antibacterial, antiviral and anti-parasitic activity. Neglected tropical diseases (NTDs) are caused by a variety of pathogens and are particularly wide-spread in low-income and developing regions of the world. Alternative, cost effective treatments are desperately needed to effectively battle these medically diverse diseases. AMPs have been shown to be effective against a variety of NTDs, including African trypanosomes, leishmaniosis and Chagas disease, trachoma and leprosy. In this review, the potential of selected AMPs to successfully treat a variety of NTD infections will be critically evaluated.
The Role of Gluten in Celiac Disease and Type 1 Diabetes
Authors: Serena Gloria , Camhi Stephanie , Sturgeon Craig , Yan Shu , Fasano Alessio
Published: August 2015

Celiac disease (CD) and type 1 diabetes (T1D) are autoimmune conditions in which dietary gluten has been proven or suggested to play a pathogenic role. In CD; gluten is established as the instigator of autoimmunity; the autoimmune process is halted by removing gluten from the diet; which allows for resolution of celiac autoimmune enteropathy and subsequent normalization of serological markers of the disease. However; an analogous causative agent has not yet been identified for T1D. Nevertheless; the role of dietary gluten in development of T1D and the potentially beneficial effect of removing gluten from the diet of patients with T1D are still debated. In this review; we discuss the comorbid occurrence of CD and T1D and explore current evidences for the specific role of gluten in both conditions; specifically focusing on current evidence on the effect of gluten on the immune system and the gut microbiota.
Central America in Transition: From Maize to Wheat Challenges and Opportunities
Authors: Peña Amado , Crusius Jakob
Published: August 2015

The Central American countries: Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama are in transition from a dietary culture based mainly on maize to a wheat-containing diet. Several other changes are occurring, such as a decrease of parasitic and infectious diseases. The environmental changes permit a prediction of an increase of celiac disease and other autoimmune diseases such as type I diabetes and thyroid disease in these genetically heterogeneous countries. At present, celiac disease and gluten-related disorders are considered to be of no relevance at the level of public health in these nations. This review documents the presence of celiac disease in Central America. It draws attention to some of the challenges in planning systematic studies in the region since up until recently celiac disease was unknown. The aim of this review is to disseminate knowledge obtained with preliminary data, to stimulate clinical and basic scientists to study these diseases in Central America and to alert authorities responsible for the planning of education and health, to find possibilities to avoid a rise in these disorders before the epidemics start, as has occurred in the Mediterranean countries.
Effects of DMT and TMPTMA on Working Life of Acrylic Polymer Concrete Exposed to Low Curing Temperatures
Authors: Yeon Kyu-Seok , Cha Jin-Yun , Yeon Jung
Published: August 2015

Ensuring an appropriate casting time window is of great importance for achieving desired quality and performance of aging materials. In this paper, the effects of promoter and cross-linking agent on the working life—the period a mixture stays in a workable condition—of low-temperature-cured acrylic polymer concrete (PC) are investigated in order to develop mixture proportions that can be effectively applied in cold weather conditions. The experimental variables included in this study are: (1) curing temperatures (−20, −10 and 0 °C); (2) N,N-dimethyl-p-toluidine (DMT) contents (0.5, 1.0, 1.5 and 2.0 phr (parts per hundred parts of resin)); and (3) trimethylolpropane trimethacrylate (TMPTMA) contents (0, 2.5 and 5 phr). Results indicated a strong relevance between binder’s setting time and PC’s working life. Additionally, it was observed that the working life of acrylic PC was substantially shortened as the curing temperature and contents of DMT and TMPTMA increased. Results of a two-way analysis of variance (ANOVA) revealed that TMPTMA had a greater impact on the working life than DMT. Finally, this study developed an equation that can be used to estimate PC working life, based on the binder’s setting time. The findings of this study will be used as valuable information for cold weather applications of acrylic PC.
Ethnography of Religious Instants: Multi-Sited Ethnography and the Idea of “Third Spaces”
Authors: Murchison Julian , Coats Curtis
Published: August 2015

Attempts to understand contemporary religious practice, and its associated communities and identities, must take into consideration the way that these phenomena exist in both virtual and physical spaces, as well as the way that, in some instances, religion bridges or erases this dichotomy. The approach here focuses on those forms of religious practice that do not fit easily into one or the other type of space. Starting with existing discussions of ethnographic methodologies for studying religious practice and the growing literature on how to study “digital religion”, we examine the methodological needs for studying “third spaces”, the hybrid, in-between spaces of religious practice. The model presented here is one of simultaneous and collaborative ethnography that extends shared methods across the virtual and the actual dimensions as the most productive approach to this type of research. Using tailored research methods and techniques within this approach offers the opportunity to consider ways in which behaviors, interactions, and speech acts that happen within this event are continuous or discontinuous with each other. It also offers insight into the dynamics of “shared experience” and how perspectives are or are not shared within these multiple dimensions.
Belief into Action Scale: A Comprehensive and Sensitive Measure of Religious Involvement
Authors: Koenig Harold , Wang Zhizhong , Al Zaben Faten , Adi Ahmad
Published: August 2015

We describe here a new measure of religious commitment, the Belief into Action (BIAC) scale. This measure was designed to be a comprehensive and sensitive measure of religious involvement that could discriminate individuals across the religious spectrum, and avoid the problem of ceiling effects that have haunted the study of highly-religious populations. Many scales assess religious beliefs, where assent to belief is often widespread, subjective, and a superficial assessment of religious commitment. While people may say they believe, what does that mean in terms of action? This 10-item scale seeks to convert simple belief into action, where action is assessed in terms of what individuals say is most important in their lives, how they spend their time, and where they put their financial resources. We summarize here the psychometric characteristics of the BIAC in two very different populations: stressed female caregivers in Southern California and North Carolina, and college students attending three universities in Mainland China. We conclude that the BIAC is a sensitive, reliable, and valid measure of religious commitment in these two samples, and encourage research in other population groups using this scale to determine its psychometric properties more generally.
Phenological Response of an Arizona Dryland Forest to Short-Term Climatic Extremes
Authors: Walker Jessica , De Beurs Kirsten , Wynne Randolph
Published: August 2015

Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the phenological patterns of an Arizona, USA, ponderosa pine (Pinus ponderosa) forest during a five-year period (2005 to 2009) that encompassed extreme wet and dry precipitation regimes. We assembled 80 synthetic Landsat images by applying the spatial and temporal adaptive reflectance fusion method (STARFM) to 500 m MODIS and 30 m Landsat-5 Thematic Mapper (TM) data. We tested relationships between site characteristics and the timing of peak Normalized Difference Vegetation Index (NDVI) to assess the effect of climatic stress on the green-up of individual pixels during or after the summer monsoon. Our results show that drought-induced stress led to a fragmented phenological response that was highly dependent on microsite parameters, as both the spatial autocorrelation of peak timing and the number of significant site variables increased during the drought year. Pixels at lower elevations and with higher proportions of herbaceous vegetation were more likely to exhibit dynamic responses to changes in precipitation conditions. Our study demonstrates the complexity of responses within dryland forest ecosystems and highlights the need for standardized monitoring of phenology trends in these areas. The spatial and temporal variability of phenological signals may provide a quantitative solution to the problem of how to evaluate dryland land surface trends across time.
Sustainable Land Management in Mining Areas in Serbia and Romania
Authors: Popović Vesna , Miljković Jelena , Subić Jonel , Jean-Vasile Andrei , Adrian Nedelcu , Nicolăescu Eugen
Published: August 2015

The paper analyzes the impacts of mining activities on sustainable land management in mining areas in the Republic of Serbia and Romania and discusses the main challenges related to the management of these issues in legislation and practice. Particular attention is paid to land disturbance, mine waste management and land reclamation, as well as access to land for mining purposes, the transfer of mining royalties and the partnerships of the mining industry, governments, communities and civil society for sustainable mining. Both governments are willing to provide the adequate role to mining in strengthening the national economies, but they face numerous constraints in this matter. Sustainable mining practices and consistent implementation of the mining for the closure planning approach, within an improved legislative framework and in cooperation with stakeholders at all levels, create conditions for the development of creative, profitable, environmentally-sound and socially-responsible management and reuse of mine lands.
A (1+2)-Dimensional Simplified Keller–Segel Model: Lie Symmetry and Exact Solutions
Authors: Didovych Maksym
Published: August 2015

This research is a natural continuation of the recent paper “Exact solutions of the simplified Keller–Segel model” (Commun Nonlinear Sci Numer Simulat 2013, 18, 2960–2971). It is shown that a (1+2)-dimensional Keller–Segel type system is invariant with respect infinite-dimensional Lie algebra. All possible maximal algebras of invariance of the Neumann boundary value problems based on the Keller–Segel system in question were found. Lie symmetry operators are used for constructing exact solutions of some boundary value problems. Moreover, it is proved that the boundary value problem for the (1+1)-dimensional Keller–Segel system with specific boundary conditions can be linearized and solved in an explicit form.
Effects of a Calcium Bentonite Clay in Diets Containing Aflatoxin when Measuring Liver Residues of Aflatoxin B1 in Starter Broiler Chicks
Authors: Fowler Justin , Li Wei , Bailey Christopher
Published: August 2015

Research has shown success using clay-based binders to adsorb aflatoxin in animal feeds; however, no adsorbent has been approved for the prevention or treatment of aflatoxicosis. In this study, growth and relative organ weights were evaluated along with a residue analysis for aflatoxin B1 in liver tissue collected from broiler chickens consuming dietary aflatoxin (0, 600, 1200, and 1800 µg/kg) both with and without 0.2% of a calcium bentonite clay additive (TX4). After one week, only the combined measure of a broiler productivity index was significantly affected by 1800 µg/kg aflatoxin. However, once birds had consumed treatment diets for two weeks, body weights and relative kidney weights were affected by the lowest concentration. Then, during the third week, body weights, feed conversion, and the productivity index were affected by the 600 µg/kg level. Results also showed that 0.2% TX4 was effective at reducing the accumulation of aflatoxin B1 residues in the liver and improving livability in birds fed aflatoxin. The time required to clear all residues from the liver was less than one week. With evidence that the liver’s ability to process aflatoxin becomes relatively efficient within three weeks, this would imply that an alternative strategy for handling aflatoxin contamination in feed could be to allow a short, punctuated exposure to a higher level, so long as that exposure is followed by at least a week of a withdrawal period on a clean diet free of aflatoxin.
Impacts of the 2013 Extreme Flood in Northeast China on Regional Groundwater Depth and Quality
Authors: Wang Xihua , Zhang Guangxin , Xu Yi
Published: August 2015

Flooding’s impact on shallow groundwater is not well investigated. In this study, we analyzed changes in the depth and quality of a regional shallow aquifer in the 10.9 × 104 km2 Sanjiang Plain, Northeast China, following a large flood in the summer of 2013. Pre- (2008–2012) and post-flood records on groundwater table depth and groundwater chemistry were gathered from 20 wells across the region. Spatial variability of groundwater recharge after the flood was assessed and the changes in groundwater quality in the post-flood period were determined. The study found a considerable increase in the groundwater table after the 2013 summer flood across the region, with the largest (3.20 m) and fastest (0.80 m·s−1) rising height occurring in western Sanjiang Plain. The rising height and velocity gradually declined from the west to the east of the plain. For the entire region, we estimated an average recharge height of 1.24 m for the four flood months (June to September) of 2013. Furthermore, we found that the extreme flood reduced nitrate (NO3−) and chloride (Cl−) concentrations and electrical conductivity (EC) in shallow groundwater in the areas that were close to rivers, but increased NO3− and Cl− concentrations and EC in the areas that were under intensive agricultural practices. As the region’s groundwater storage and quality have been declining due to the rapidly increasing rice cultivation, this study shows that floods should be managed as water resources to ease the local water shortage as well as shallow groundwater pollution.
Improved Drinking Water Disinfection with UVC-LEDs for Escherichia Coli and Bacillus Subtilis Utilizing Quartz Tubes as Light Guide
Authors: Gross Andrej , Stangl Felix , Hoenes Katharina , Sift Michael , Hessling Martin
Published: August 2015

A new approach is investigated utilizing light guidance capabilities of optical pure quartz glass in order to maximize drinking water disinfection efficiency with UVC-light-emitting diodes (LEDs). Two experimental setups consisting of soda-lime AR® glass (VWR, Darmstadt, Germany) or HSQ® 100 quartz glass (Heraeus, Wasserburg, Germany) reactors were designed to compare disinfection rates with and without total reflection of UVC radiation along the reactor walls. Each reactor was filled with 9 mL bacteria samples containing either E. coli DSM (Deutsche Sammlung von Mikroorganismen) 498 or B. subtilis DSM 402 strains (concentration 1–3 × 106 colony forming units (CFU)/mL) with and without additional mixing and irradiation periods of 10, 40, and 90 s. Disinfection rates were increased up to 0.95 log10 (E. coli) and 0.75 log10 (B. subtilis) by the light guide approach in stagnant samples. The same experiments with mixing of the samples resulted in an increased disinfection efficiency of 3.07 log10 (E. coli) and 1.59 log10 (B. subtilis). Optical calculations determine that total reflection is achieved with the applied UVC-LED’s viewing angle of 15°. Furthermore measurements show that HSQ® 100 quartz has a transmittance of 92% at 280 nm UVC irradiation compared to the transmittance of soda-lime glass of 2% (1 mm wall thickness).
NanoE-Tox: New and in-depth database concerning ecotoxicity of nanomaterials
Authors: Juganson Katre , Ivask Angela , Blinova Irina , Mortimer Monika , Kahru Anne
Published: August 2015

The increasing production and use of engineered nanomaterials (ENMs) inevitably results in their higher concentrations in the environment. This may lead to undesirable environmental effects and thus warrants risk assessment. The ecotoxicity testing of a wide variety of ENMs rapidly evolving in the market is costly but also ethically questionable when bioassays with vertebrates are conducted. Therefore, alternative methods, e.g., models for predicting toxicity mechanisms of ENMs based on their physico-chemical properties (e.g., quantitative (nano)structure-activity relationships, QSARs/QNARs), should be developed. While the development of such models relies on good-quality experimental toxicity data, most of the available data in the literature even for the same test species are highly variable. In order to map and analyse the state of the art of the existing nanoecotoxicological information suitable for QNARs, we created a database NanoE-Tox that is available as Supporting Information File 2. The database is based on existing literature on ecotoxicology of eight ENMs with different chemical composition: carbon nanotubes (CNTs), fullerenes, silver (Ag), titanium dioxide (TiO2), zinc oxide (ZnO), cerium dioxide (CeO2), copper oxide (CuO), and iron oxide (FeOx; Fe2O3, Fe3O4). Altogether, NanoE-Tox database consolidates data from 224 articles and lists altogether 1,518 toxicity values (EC50/LC50/NOEC) with corresponding test conditions and physico-chemical parameters of the ENMs as well as reported toxicity mechanisms and uptake of ENMs in the organisms. 35% of the data in NanoE-Tox concerns ecotoxicity of Ag NPs, followed by TiO2 (22%), CeO2 (13%), and ZnO (10%). Most of the data originates from studies with crustaceans (26%), bacteria (17%), fish (13%), and algae (11%). Based on the median toxicity values of the most sensitive organism (data derived from three or more articles) the toxicity order was as follows: Ag > ZnO > CuO > CeO2 > CNTs > TiO2 > FeOx. We believe NanoE-Tox database contains valuable information for ENM environmental hazard estimation and development of models for predicting toxic potential of ENMs.
AN INTRODUCTION OF KRILL HERD ALGORITHM FOR ENGINEERING OPTIMIZATION
Authors: GANDOMI Amir H. , ALAVI Amir H.
Published: August 2015

A new metaheuristic optimization algorithm, called Krill Herd (KH), has been recently proposed by Gandomi and Alavi (2012). In this study, KH is introduced for solving engineering optimization problems. For more verification, KH is applied to six design problems reported in the literature. Further, the performance of the KH algorithm is com­pared with that of various algorithms representative of the state-of-the-art in the area. The comparisons show that the results obtained by KH are better than the best solutions obtained by the existing methods.
EFFECT OF STIRRUP CORROSION ON THE SHEAR STRENGTH OF REINFORCED CONCRETE SHORT BEAMS
Authors: EL-SAYED Ahmed K. , HUSSAIN Raja R. , SHURAIM Ahmed B.
Published: August 2015

The effect of stirrups damage due to corrosion on the shear strength and behaviour of reinforced concrete beams was experimentally investigated. A total of fourteen full-scale reinforced concrete beams were constructed and tested under four-point bending up to failure. The test beams were 200 mm wide, 350 mm deep, and 2800 mm long. The reinforcing stirrups of nine of the beams were subjected to accelerated corrosion prior to structural testing. The test variables were the corrosion damage level, spacing of stirrups, and shear span to depth ratio. The beams were tested under shear span to depth ratio of 2 or 1 representing short or deep members. The test results indicated that the corroded beams exhibited degradation in stiffness and shear strength in comparison to the uncorroded control specimens. This degradation appeared to increase as the corrosion level increases and as stirrup spacing as well as shear span to depth ratio decreases.
Antenna System and Architecture-Circular Polarized UWB Antenna for Indoor Positioning Application
Authors: Kumar Rupesh , Huyart Bernard , Cousin Jean-Christophe
Published: August 2015

Indoor environment can be characterized as sever attenuating and depolarizing medium for electromagnetic (radio) waves propagation. These signals are radiated from transmitters to space (free-space propagation channel) and received from space to receivers through antennas. These signals are commonly radiated or received with pre-defined signal's polarization schemes and these schemes are always controlled by the antenna. In this chapter, the two-dimensional antenna designs and its polarization schemes are presented for minimizing the sever effects of an indoor environment. Emphasis is on understanding the special attention required for designing an antenna dedicated to an Indoor Positioning/Localization System. Some recent developments in antenna designs are presented as an example for the better understanding and its future perspective.
Applications of Advanced Reconfigurable Antenna for the Next Generation 4G Communication Devices
Authors: Donelli Massimo
Published: August 2015

The objective of this chapter is to show the applications of innovative reconfigurable antenna methodologies for the 4G devices. Microwave antenna technology can be very useful for the 4G devices, because these products will require high bandwidth and high velocity channel with respect to conventional antennas. This chapter presents a complete picture of possible applications of advanced microwave technologies for 4G devices and systems, it includes methodologies, such as phased and fully adaptive arrays, innovative multiple-Input and multiple-output (MIMO) antennas based on compact rotmans lenses or butler matrix, and the development of innovate reconfigurable antenna based on reconfigurable parasitic structures. The chapter ends with some conclusions and considerations related to ideas for future works.
Future M2M Communication Networks
Authors: Vassaki Stavroula , Pitsiladis George , Sagkriotis Stavros E. , Panagopoulos Athanasios D.
Published: August 2015

Machine type communications (or Machine-to-Machine / M2M) communications have emerged as an important paradigm in wireless communication networks. The current M2M standardization activities are presented and their implementation in 4G/LTE networks is described in detail. The chapter is divided in three parts that are related to the evolution of the Future M2M communication Networks. The first part focuses on existing random access management schemes for M2M communications that are presented in the literature. The second part is devoted on spectrum sharing methods and on M2M clustering and it presents the spatial distribution of heterogeneous networks and its impact on their connectivity. Finally, the last part refers to energy efficiency issues of the future M2M communication systems and their implementation using distributed power control and MAC/scheduling algorithms.
Automated Categorisation of Nailfold Capillaroscopy Images
Authors: Doshi Niraj , Schaefer Gerald
Published: August 2015

Nailfold capillaroscopy (NC) is a non-invasive imaging technique employed to assess the condition of blood capillaries in the nailfold. It is particularly useful for early detection of scleroderma spectrum disorders and evaluation of Raynaud's phenomenon. While automated approaches to analysing NC images are relatively rare, they are typically based on extraction and analysis of individual capillaries from the images in order to assign a patient to one of the commonly employed scleroderma patterns. In this chapter, we present a different approach that does not rely on individual capillaries but performs interpretation in a holistic way based on information gathered from an image or a selected image region. In particular, our algorithm employs texture analysis to characterise the underlying patterns, coupled with a classification stage to first identify patterns in fingers, and then, through a voting strategy, reach a decision for a patient. Experimental results on a set of NC images with known ground truth demonstrate the efficacy of the proposed approach.
Assessment of Fatigue Strength in Small-Specimen of AISI 3140 Steel
Authors: Haftirman Haftirman , Basaruddin K.S. , Afendi Mohd , Syayuthi A.R.
Published: August 2015

The fatigue strength on small-specimen of mild steel material subjected to rotating bending load has been investigated. Specimen materials were used AISI 3140 steel. The tests were carried out the specimen diameter of 2 and 1 mm at laboratory air. The results obtained can be summarized that fatigue strength of diameter 2 mm was higher than that of diameter 8 and 1 mm for AISI 3140 steel material. Assessment of fatigue strength in small-specimen of carbon steel material has been done based on experimental and the cross-sectional analysis. Fatigue strength of AISI 3140 steel was lower than that of SS400 and S45C steels. The size effect concentration were determined the ratio of fatigue strength small-specimen to the normative specimen. The cross-sectional A was decrease with increasing coefficient of cross-section size. These results were significant impact of the size effect on fatigue strength on metal materials.
Characterization of Biaxial Fatigue by Using Strain Energy Density Approach for Steel
Authors: Mohamed S.A.N. , Abdullah Shahrum , Ariffin Kamal A. , Arifin Azli , Padzi Mahfodzah M.
Published: August 2015

This research discussed on the determination of the appropriate fatigue damage parameter to predict the fatigue life when material subjected to the biaxial loading condition with the consideration of the energy dissipated. Servo-hydraulic machine is used for the constant amplitude cyclic testing on smooth solid mild steel. The results showed that in the low cycle fatigue, the total strain energy density can represent the accumulative of fatigue damage and characterize on the damage parameters. The relationship has been proposed which the data satisfactorily correlated for the R2 is 0.8656. In addition, the hysteresis loop represent the area under the graph was the energy stored in the material during the loading and unloading condition. Hence the circumstances showed the deformation process governing the nucleation and propagation of fatigue cracks associated with the energy dissipated.
The Relationship between Strain Energy Release Rate with Crack-to-Width Ratio of Human Phalanx Bone
Authors: Abdul Halim Siti Aisyah , Daud Ruslizam , Bajuri Yazid , Zaaba S.K. , Basaruddin Khairul Salleh , Zain N.A.M. , Mansor Nurul Najwa
Published: August 2015

Bone fracture can occur in all parts of human skeletal cortical bone including phalanx bone of finger bone. Sometime, it leaves permanent damage and a long period of recovery. This situation can be prevented if we understand the mechanics and the process of the bone fracture. This study aims is to evaluate stress shielding induced by crack interaction using a simple model on Linear Elastic Fracture Mechanics (LEFM). Numerical simulation had been carried out in this study to understand the stress shielding induced by crack interaction. The results revealed that the interaction of two cracks is directly proportional to the stress intensity factor (SIF) magnitude at crack tips. Finally, as the crack-to-width ratio increase and the strain energy release rate also increased.
Objective Assessment of Vibration Exposure among Workforces: A Review
Authors: Khamis Nor Kamaliana , Md Deros Baba , Nuawi Mohd Zaki , Ismail Faizul Rizal
Published: August 2015

The prevalence of work related musculoskeletal problems with respect to vibration is prominent. This review paper gather recent studies related to objective assessment among work force from all over the world. The three main objectives of this review are: to analyse published objective assessment related to vibration among the work force; to extract and understand in detail the process of each assessment; and to identify whether or not there is a relationship between each variables. Twenty relevant studies were identified and chosen from electronic databases, dating as far back as 2001. “Vibration”, “musculoskeletal problem”, “worker”, and “objective measures” were the keyword search terms for this paper. Past studies demonstrated various purposes and implementation of objective assessment among the work force in evaluating vibration effects. It provides better understanding for the future researchers and industry to deal with vibration issues among work force. Many objective assessment methods among the work force have been applied in the past studies. However, they are still many concerns found in past studies that need to be investigated in the future studies. Therefore, there is a need to perform and apply different objective assessment for evaluating human vibration issues.
Effect of Heat Treatment on Microstructure, Hardness and Wear of Aluminum Alloy 332
Authors: Zainon Fizam , Ahmad Khairel Rafezi , Daud Ruslizam
Published: August 2015

This paper describes a study on the effects of heat treatment on the microstructure, hardness and wear of aluminum alloys 332 (AlSi9Cu3Mg). The solution treatment was performed at 500°C for 5 hours and then quenched in water at room temperature. Aging was performed at 170°C for 2 hours. The findings revealed that after a full heat treatment, the structure of the eutectic silicon formed toward fragmentation and spheroidization, and the silicon particles became coarse (look-like rounded). Hard intermetallic compound (Mg2Si) appeared on the microstructure after the aging treatment completed. Compared to the as-cast, the hardness of the alloys has improved to 44.84%, and the wear rate of the solution treatment had decreased to 26% while the aging treatment showed a deterioration of 79.42%. The study concludes that aging treatment improves the hardness of AA332 alloys and enhanced the wear resistance of the substance.
Finite Element Analysis of Heater Length in a Porous Annulus - Part A
Authors: Quadir Ghulam Abdul , Ahmed N.J.S , Al-Rashed A.A.A.A , Badruddin I.A. , Khaleed H.M.T. , Kamangar S.
Published: August 2015

The focus of present study is to investigate the influence of discrete heating by an isothermal heater placed at the inner radius of a vertical annular cylinder containing porous medium between its inner and the outer radius. Finite element method is used to solve the governing partial differential equations by employing 3 noded triangular elements. Darcy model is used to represent the flow behavior inside the porous medium. It is assumed that the thermal non-equilibrium condition exists between the fluid and solid phases of the porous medium. The study is conducted for different lengths of heater corresponding to 20%, 35% and 50% of the total height of the cylinder. It is found that the Nusselt number for fluid, solid phases as well as total Nusselt number initially decreases and the increases along the length of heater.
Numerical Investigation on the Effect of Injection Pressure on Melt Front Pressure and Velocity Drop
Authors: Rusdi M.S. , Abdullah Mohd Zulkifly , Mahmud Abdus Samad , Khor C.Y. , Abdul Aziz M.S. , Abdullah Muhammad Khalil , Yusoff H. , Firdaus S.M.
Published: August 2015

Computational Fluid Dynamic (CFD) was used to simulate the injection molding process of a tray. The study focuses on pressure distribution and velocity drop during the injection process. CFD simulation software ANSYS FLUENT 14 was utilized in this study. The melt front pressure in the mold cavity shows that it was affected by the shape of mold cavity and filling stage. The melt front pressure will decrease as the flow move further than the sprue but it will increase rapidly when the mold was about to be fully filled. The slight pressure drop was detected when the molten flow meets the rib of the tray. The velocity of higher injection pressure was greater than the lower injection pressure but the velocity rapidly dropped when the melt front fully filled the cavity. The current predicted flow profile was validated by the experimental results, which demonstrates the excellent capability of the simulation tool in solving injection-molding problems.
Preliminary Investigation of an Up-Scaled Gamma-Type Stirling Engine for Power Production
Authors: Hamid M.F. , Yusof Mohamad , Abdullah Muhammad Khalil , Zainal Z.A. , Miskam M.A.
Published: August 2015

This paper presents the development of Gamma-type Stirling engine for High Temperature Differential (HTD) and self-pressurized mode of operation. The engine is the up-scaled version from the Low Temperature Differential (LTD) miniaturized gamma-type Stirling engine. The test engine is featured with 85cc power piston and 4357cc displacer piston swept volumes, respectively. The characterization of few critical engine parameters and components that includes heater head section, cooler section, displacer and power pistons material selection and heat source system had been conducted. Air is used as a working fluid and Liquefied Petroleum Gas (LPG) is utilized as the heat source in order to cater for the heater temperature up to 1000°C. The workability test of the engine revealed that the lightweight in mass of the displacer piston and the auxiliary cooling effect at the cooler section had contributed to a significant improvement on the engine rotational motion. The static load test determined that the engine is capable of producing the friction power of 1.2W for stainless steel mesh wire displacer and 0.3W for polystyrene displacer. Based on Beale formula, the estimated power of 4W can be produced by the engine using stainless steel mesh wire displacer and 2.4W of power using polystyrene displacer. Good agreement has been shown, where the potential net power production of 3.8W and 2.1 W for stainless mesh wire displacer and polystyrene displacer, respectively. Further investigation is needed to improve the heat regeneration in between hot and cold sections of the engine to realize the sustainable performance of the engine at higher range of temperature difference and output power.
Power and Thermal Efficiency Study of Offshore Gas Turbines under Various Ambient Temperatures
Authors: Tahan Bouriaabadi Mohammadreza , bin Abd Majid Mohd Amin , Abd Majid Mohd Amin , Muhammad Masdi
Published: August 2015

Gas turbines offer a reduced weight and compact solution for installation on offshore platforms and floating facilities. The purpose of this study is to examine the influence of various parameters on offshore gas turbines performance. Operating measurements of a 23MW gas turbine installed at an offshore oil and gas plant in east of Peninsular Malaysia was used for model verification and evaluation. The results showed that the gas turbine performance improvements involve the study of a wide range of different parameters including ambient temperature, compression ratio, fuel-air ratio and operating load. These achieved relations will help in appropriate assessment of offshore gas turbines thermal efficiency.
Numerical Study of Mold Filling during Encapsulation Process
Authors: Hamid M.F. , Abdullah Muhammad Khalil , Yusoff H. , Firdaus Sheikh Mohd , Abdullah Mohd Zulkifly , Ariff Zulkifli Mohamad , Azmi M.A.
Published: August 2015

3-D packaging is a technology that offers high density packaging and high performance. It enables chips to be stack in a single package and widely adopted in multi-media products. Thermosetting material is used for their encapsulation, is flowed through their thin space and wide filling area during package encapsulation process has become vital concern i.e. void formation. In this paper, such issue has been numerical studied due to the effect of transfer speed of the plunger head during encapsulation process. There are five transfer speeds of 1.6, 2.0, 3.4, 6.8, 9.04 mm/s have been chosen in order to investigate the quality of air entrapped (hereafter namely as void), where it degraded the package’s reliability. It is found that the longest transfer speed delivered to the best encapsulation process, which had lowest volume of air trap or void formation in the package.Keywords: Encapsulation, Transfer speed, Vent arrangement, Void Formation
Investigation on the Effect of B2O3 Additive on Microstructure and Magnetic Properties of Barium Hexaferrite
Authors: Sari A.Y. , Ginting D. , Sebayang P. , Sardjono P. , Kurniawan C. , Nasrudin M.N.
Published: August 2015

The effects of B2O3 addition (0, 0.2, 0.5, 1 and 2 wt %) on the change of microstructure and magnetic properties of barium hexaferrite (BHF) has been made and analyzed. The purpose of this work is to higher the magnetic properties of BHF by B2O3 additive. It was found that the distribution average diameter particle, true density, sintered density, and magnetic flux density of BHF are modified obviously as a small amount of B2O3 is added. The best quality of materials is obtained which 0.5 wt % B2O3 addition and showed excellent properties with average particle size of 1.78 µm , true density of 5.00 g/cm3, sintered density of 4,66 g/cm3, and flux density of 722.5 Gauss. Furthermore, the surface morphology by SEM revealed that the grain is around 1.2 µm and more homogeneity. The results can be interpreted that the preferential addition of B2O3 at low level is 0.5 wt%.
The Pozzoolanic Activity Level of Powder Waste Glass in Comparisons with other Powders
Authors: Corbu Ofelia , Ioani Adrian M. , Al Bakri A.M. Mustafa , Meiţă Vasile , Szilagyi Henriette , Sandu Andrei Victor
Published: August 2015

In order to streamline the mixes of concrete with powder waste glass as small as < 0.250 mm, a postdoctoral program objective was to test the activity rate of its pozzoolanic reaction, through various methods and by comparing it with other powders reactions in a standardized cement composition. The first method was to determine the compressive strength of cement mortars, partially substituted by glass powder, silica fume, ash and clay. The second method was determining the chemical composition of the powder with fluorescence X-ray, XRF type. The third method, was based on fragments of mortar studied and subjected to microscopic observations – SEM determination (scanning electron microscopy) to investigate the microstructure of the raw material.