bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanization of Conservation Agriculture for Smallholders: Issues and Options for Sustainable Intensification
Authors: Sims Brian , Kienzle Josef
Published: May 2015

Conservation agriculture (CA) is an increasingly adopted production system to meet the goals of sustainable crop production intensification in feeding a growing world population whilst conserving natural resources. Mechanization (especially power units, seeders, rippers and sprayers) is a key input for CA and smallholder farmers often have difficulties in making the necessary investments. Donors may be able to provide mechanization inputs in the short term, but this is not a sustainable solution as a machinery input supply chain needs to be built up to continue availability after external interventions cease. Local manufacture should be supported, as was the case in Brazil, but this is a slow development process, especially in sub-Saharan Africa. A more immediate solution is to equip and train CA service provision entrepreneurs. With the right equipment, selected for the needs of their local clientele, and the right technical and business management training, such entrepreneurs can make a livelihood by supplying high quality CA and other mechanization services on a fully costed basis. Elements of the required training, based on extensive field experience, are provided. To catalyse the growth of CA providers’ business, the market can be stimulated for an initial period by issuing e-vouchers for services and inputs.
An Assessment of Indoor Air Quality before, during and after Unrestricted Use of E-Cigarettes in a Small Room
Authors: O'Connell Grant , Colard Stéphane , Cahours Xavier , Pritchard John
Published: May 2015

Airborne chemicals in the indoor environment arise from a wide variety of sources such as burning fuels and cooking, construction materials and furniture, environmental tobacco smoke as well as outdoor sources. To understand the contribution of exhaled e-cigarette aerosol to the pre-existing chemicals in the ambient air, an indoor air quality study was conducted to measure volatile organic compounds (including nicotine and low molecular weight carbonyls), polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines and trace metal levels in the air before, during and after e-cigarette use in a typical small office meeting room. Measurements were compared with human Health Criteria Values, such as indoor air quality guidelines or workplace exposure limits where established, to provide a context for potential bystander exposures. In this study, the data suggest that any additional chemicals present in indoor air from the exhaled e-cigarette aerosol, are unlikely to present an air quality issue to bystanders at the levels measured when compared to the regulatory standards that are used for workplaces or general indoor air quality.
Molecular Detection of a Potentially Toxic Diatom Species
Authors: Dhar Bidhan , Cimarelli Lucia , Singh Kumar , Brandi Letizia , Brandi Anna , Puccinelli Camilla , Marcheggiani Stefania , Spurio Roberto
Published: May 2015

A few diatom species produce toxins that affect human and animal health. Among these, members of the Pseudo-nitzschia genus were the first diatoms unambiguously identified as producer of domoic acid, a neurotoxin affecting molluscan shell-fish, birds, marine mammals, and humans. Evidence exists indicating the involvement of another diatom genus, Amphora, as a potential producer of domoic acid. We present a strategy for the detection of the diatom species Amphora coffeaeformis based on the development of species-specific oligonucleotide probes and their application in microarray hybridization experiments. This approach is based on the use of two marker genes highly conserved in all diatoms, but endowed with sufficient genetic divergence to discriminate diatoms at the species level. A region of approximately 450 bp of these previously unexplored marker genes, coding for elongation factor 1-a (eEF1-a) and silicic acid transporter (SIT), was used to design oligonucleotide probes that were tested for specificity in combination with the corresponding fluorescently labeled DNA targets. The results presented in this work suggest a possible use of this DNA chip technology for the selective detection of A. coffeaeformis in environmental settings where the presence of this potential toxin producer may represent a threat to human and animal health. In addition, the same basic approach can be adapted to a wider range of diatoms for the simultaneous detection of microorganisms used as biomarkers of different water quality levels.
Mechanism of Action of IL-7 and Its Potential Applications and Limitations in Cancer Immunotherapy
Authors: Gao Jianbao , Zhao Lintao , Wan Yisong , Zhu Bo
Published: May 2015

Interleukin-7 (IL-7) is a non-hematopoietic cell-derived cytokine with a central role in the adaptive immune system. It promotes lymphocyte development in the thymus and maintains survival of naive and memory T cell homeostasis in the periphery. Moreover, it is important for the organogenesis of lymph nodes (LN) and for the maintenance of activated T cells recruited into the secondary lymphoid organs (SLOs). The immune capacity of cancer patients is suppressed that is characterized by lower T cell counts, less effector immune cells infiltration, higher levels of exhausted effector cells and higher levels of immunosuppressive cytokines, such as transforming growth factor β (TGF-β). Recombinant human IL-7 (rhIL-7) is an ideal solution for the immune reconstitution of lymphopenia patients by promoting peripheral T cell expansion. Furthermore, it can antagonize the immunosuppressive network. In animal models, IL-7 has been proven to prolong the survival of tumor-bearing hosts. In this review, we will focus on the mechanism of action and applications of IL-7 in cancer immunotherapy and the potential restrictions for its usage.
Action at a Distance in Quantum Theory
Authors: Blackman Jerome
Published: May 2015

The purpose of this paper is to present a consistent mathematical framework that shows how the EPR (Einstein. Podolsky, Rosen) phenomenon fits into our view of space time. To resolve the differences between the Hilbert space structure of quantum theory and the manifold structure of classical physics, the manifold is taken as a partial representation of the Hilbert space. It is the partial nature of the representation that allows for action at a distance and the failure of the manifold picture.
Perspective on the Use of Sulfated Polysaccharides from Marine Organisms as a Source of New Antithrombotic Drugs
Authors: Mourão Paulo
Published: May 2015

Thromboembolic diseases are increasing worldwide and always require anticoagulant therapy. We still need safer and more secure antithrombotic drugs than those presently available. Sulfated polysaccharides from marine organisms may constitute a new source for the development of such drugs. Investigation of these compounds usually attempts to reproduce the therapeutic effects of heparin. However, we may need to follow different routes, focusing particularly in the following aspects: (1) defining precisely the specific structures required for interaction of these sulfated polysaccharides with proteins of the coagulation system; (2) looking for alternative mechanisms of action, distinct from those of heparin; (3) identifying side effects (mostly pro-coagulant action and hypotension rather than bleeding) and preparing derivatives that retain the desired antithrombotic action but are devoid of side effects; (4) considering that sulfated polysaccharides with low anticoagulant action on in vitro assays may display potent effects on animal models of experimental thrombosis; and finally (5) investigating the antithrombotic effect of these sulfated polysaccharides after oral administration or preparing derivatives that may achieve this effect. If these aspects are successfully addressed, sulfated polysaccharides from marine organisms may conquer the frontier of antithrombotic therapy and open new avenues for treatment or prevention of thromboembolic diseases.
Tilapia Piscidin 4 (TP4) Stimulates Cell Proliferation and Wound Closure in MRSA-Infected Wounds in Mice
Authors: Huang Hang-Ning , Chan Yi-Lin , Wu Chang-Jer , Chen Jyh-Yih
Published: May 2015

Antimicrobial peptides (AMPs) are endogenous antibiotics that directly affect microorganisms, and also have a variety of receptor-mediated functions. One such AMP, Tilapia piscidin 4 (TP4), was isolated from Nile tilapia (Oreochromis niloticus); TP4 has antibacterial effects and regulates the innate immune system. The aim of the present study was to characterize the role of TP4 in the regulation of wound closure in mice and proliferation of a keratinocyte cell line (HaCaT) and fibroblast cell line (Hs-68). In vitro, TP4 stimulated cell proliferation and activated collagen I, collagen III, and keratinocyte growth factor (KGF) gene expression in Hs-68 cells, which induces keratin production by HaCaT cells. This effect was detectable at TP4 concentrations of 6.25 µg/mL in both cell lines. In vivo, TP4 was found to be highly effective at combating peritonitis and wound infection caused by MRSA in mouse models, without inducing adverse behavioral effects or liver or kidney toxicity. Taken together, our results indicate that TP4 enhances the survival rate of mice infected with the bacterial pathogen MRSA through both antimicrobial and wound closure activities mediated by epidermal growth factor (EGF), transforming growth factor (TGF), and vascular endothelial growth factor (VEGF). The peptide is likely involved in antibacterial processes and regulation of tissue homeostasis in infected wounds in mice. Overall, these results suggest that TP4 may be suitable for development as a novel topical agent for wound dressing.
Synthesis, Antimicrobial and Hypoglycemic Activities of Novel N-(1-Adamantyl)carbothioamide Derivatives
Authors: Al-Abdullah Ebtehal , Al-Tuwaijri Hanaa , Hassan Hanan , Al-Alshaikh Monirah , Habib Elsayed , El-Emam Ali
Published: May 2015

The reaction of 1-adamantyl isothiocyanate 4 with the various cyclic secondary amines yielded the corresponding N-(1-adamantyl)carbothioamides 5a–e, 6, 7, 8a–c and 9. Similarly, the reaction of 4 with piperazine and trans-2,5-dimethylpiperazine in 2:1 molar ratio yielded the corresponding N,N'-bis(1-adamantyl)piperazine-1,4-dicarbothioamides 10a and 10b, respectively. The reaction of N-(1-adamantyl)-4-ethoxycarbonylpiperidine-1-carbothioamide 8c with excess hydrazine hydrate yielded the target carbohydrazide 11, in addition to 4-(1-adamantyl)thiosemicarbazide 12 as a minor product. The reaction of the carbohydrazide 11 with methyl or phenyl isothiocyanate followed by heating in aqueous sodium hydroxide yielded the 1,2,4-triazole analogues 14a and 14b. The reaction of the carbohydrazide 11 with various aromatic aldehydes yielded the corresponding N'-arylideneamino derivatives 15a–g. The compounds 5a–e, 6, 7, 8a–c, 9, 10a, 10b, 14a, 14b and 15a–g were tested for in vitro antimicrobial activity against certain strains of pathogenic Gram-positive and Gram-negative bacteria and the yeast-like fungus Candida albicans. The compounds 5c, 5d, 5e, 6, 7, 10a, 10b, 15a, 15f and 15g showed potent antibacterial activity against one or more of the tested microorganisms. The oral hypoglycemic activity of compounds 5c, 6, 8b, 9, 14a and 15b was determined in streptozotocin (STZ)-induced diabetic rats. Compound 5c produced significant reduction of serum glucose levels, compared to gliclazide.
Phylum Level Change in the Cecal and Fecal Gut Communities of Rats Fed Diets Containing Different Fermentable Substrates Supports a Role for Nitrogen as a Factor Contributing to Community Structure
Authors: Kalmokoff Martin , Franklin Jeff , Petronella Nicholas , Green Judy , Brooks Stephen
Published: May 2015

Fermentation differs between the proximal and distal gut but little is known regarding how the bacterial communities differ or how they are influenced by diet. In order to investigate this, we compared community diversity in the cecum and feces of rats by 16S rRNA gene content and DNA shot gun metagenomics after feeding purified diets containing different fermentable substrates. Gut community composition was dependent on the source of fermentable substrate included in the diet. Cecal communities were dominated by Firmicutes, and contained a higher abundance of Lachnospiraceae compared to feces. In feces, community structure was shifted by varying degrees depending on diet towards the Bacteroidetes, although this change was not always evident from 16S rRNA gene data. Multi-dimensional scaling analysis (PCoA) comparing cecal and fecal metagenomes grouped by location within the gut rather than by diet, suggesting that factors in addition to substrate were important for community change in the distal gut. Differentially abundant genes in each environment supported this shift away from the Firmicutes in the cecum (e.g., motility) towards the Bacteroidetes in feces (e.g., Bacteroidales transposons). We suggest that this phylum level change reflects a shift to ammonia as the primary source of nitrogen used to support continued microbial growth in the distal gut.
Synthesis and Thermosensitive Behavior of Polyacrylamide Copolymers and Their Applications in Smart Textiles
Authors: Chen Tao , Fang Qisheng , Zhong Qi , Chen Yangyi , Wang Jiping
Published: May 2015

We tuned the lower critical solution temperature (LCST) of amphiphilic poly(N-isopropylacrylamide) (PNIPAAm) via copolymerization with a hydrophilic comonomer of N-hydroxymethyl acrylamide (NHMAAm). A series of copolymers P(NIPAAm-co-NHMAAm) were synthesized by atom transfer radical polymerization (ATRP) using CuBr/(N,N,N',N',N''-Pentamethyldiethylenetriamine) (PMDETA) as a catalyst system and 2-bromo ethyl isobutyrate (EBiB) as an initiator. The copolymers were well characterized by Fourier transform infrared spectroscopy (FT-IR), 1H Nuclear magnetic resonance (NMR), and Thermogravimetric analysis (TGA). The copolymers followed a simple rule in their thermosensitive behaviors and have a linear increase in the LCST as a function of NHMAAm mol%. The thermosensitive properties of the copolymer films were investigated and demonstrated hydrophilic-hydrophobic transitions. Finally, the copolymer was grafted onto cotton fabrics using citric acid (CA) as a crosslinking agent and sodium hypophosphite (SHP) as a catalyst following a two dipping, two padding process. The large number of hydroxyl groups in the copolymer makes grafting convenient and firm. The grafted cotton fabrics show obvious thermosensitive behaviors. The results demonstrate that the cotton fabrics become more hydrophobic when the temperature is higher than the LCST. This study presents a valuable route towards temperature-responsive smart textiles and their potential applications.
Collaborative Localization and Location Verification in WSNs
Authors: Miao Chunyu , Dai Guoyong , Ying Kezhen , Chen Qingzhang
Published: May 2015

Localization is one of the most important technologies in wireless sensor networks. A lightweight distributed node localization scheme is proposed by considering the limited computational capacity of WSNs. The proposed scheme introduces the virtual force model to determine the location by incremental refinement. Aiming at solving the drifting problem and malicious anchor problem, a location verification algorithm based on the virtual force mode is presented. In addition, an anchor promotion algorithm using the localization reliability model is proposed to re-locate the drifted nodes. Extended simulation experiments indicate that the localization algorithm has relatively high precision and the location verification algorithm has relatively high accuracy. The communication overhead of these algorithms is relative low, and the whole set of reliable localization methods is practical as well as comprehensive.
Intelligent Simultaneous Quantitative Online Analysis of Environmental Trace Heavy Metals with Total-Reflection X-Ray Fluorescence
Authors: Ma Junjie , Wang Yeyao , Yang Qi , Liu Yubing , Shi Ping
Published: May 2015

Total-reflection X-ray fluorescence (TXRF) has achieved remarkable success with the advantages of simultaneous multi-element analysis capability, decreased background noise, no matrix effects, wide dynamic range, ease of operation, and potential of trace analysis. Simultaneous quantitative online analysis of trace heavy metals is urgently required by dynamic environmental monitoring and management, and TXRF has potential in this application domain. However, it calls for an online analysis scheme based on TXRF as well as a robust and rapid quantification method, which have not been well explored yet. Besides, spectral overlapping and background effects may lead to loss of accuracy or even faulty results during practical quantitative TXRF analysis. This paper proposes an intelligent, multi-element quantification method according to the established online TXRF analysis platform. In the intelligent quantification method, collected characteristic curves of all existing elements and a pre-estimated background curve in the whole spectrum scope are used to approximate the measured spectrum. A novel hybrid algorithm, PSO-RBFN-SA, is designed to solve the curve-fitting problem, with offline global optimization and fast online computing. Experimental results verify that simultaneous quantification of trace heavy metals, including Cr, Mn, Fe, Co, Ni, Cu and Zn, is realized on the online TXRF analysis platform, and both high measurement precision and computational efficiency are obtained.
Classifying Step and Spin Turns Using Wireless Gyroscopes and Implications for Fall Risk Assessments
Authors: Fino Peter , Frames Christopher , Lockhart Thurmon
Published: May 2015

Recent studies have reported a greater prevalence of spin turns, which are more unstable than step turns, in older adults compared to young adults in laboratory settings. Currently, turning strategies can only be identified through visual observation, either in-person or through video. This paper presents two unique methods and their combination to remotely monitor turning behavior using three uniaxial gyroscopes. Five young adults performed 90° turns at slow, normal, and fast walking speeds around a variety of obstacles while instrumented with three IMUs (attached on the trunk, left and right shank). Raw data from 360 trials were analyzed. Compared to visual classification, the two IMU methods’ sensitivity/specificity to detecting spin turns were 76.1%/76.7% and 76.1%/84.4%, respectively. When the two methods were combined, the IMU had an overall 86.8% sensitivity and 92.2% specificity, with 89.4%/100% sensitivity/specificity at slow speeds. This combined method can be implemented into wireless fall prevention systems and used to identify increased use of spin turns. This method allows for longitudinal monitoring of turning strategies and allows researchers to test for potential associations between the frequency of spin turns and clinically relevant outcomes (e.g., falls) in non-laboratory settings.
A Label-Free Impedimetric DNA Sensor Based on a Nanoporous SnO2 Film: Fabrication and Detection Performance
Authors: Le Minh , Jimenez Carmen , Chainet Eric , Stambouli Valerie
Published: May 2015

Nanoporous SnO2 thin films were elaborated to serve as sensing electrodes for label-free DNA detection using electrochemical impedance spectroscopy (EIS). Films were deposited by an electrodeposition process (EDP). Then the non-Faradic EIS behaviour was thoroughly investigated during some different steps of functionalization up to DNA hybridization. The results have shown a systematic decrease of the impedance upon DNA hybridization. The impedance decrease is attributed to an enhanced penetration of ionic species within the film volume. Besides, the comparison of impedance variations upon DNA hybridization between the liquid and vapour phase processes for organosilane (APTES) grafting on the nanoporous SnO2 films showed that vapour-phase method is more efficient. This is due to the fact that the vapour is more effective than the solution in penetrating the nanopores of the films. As a result, the DNA sensors built from vapour-treated silane layer exhibit a higher sensitivity than those produced from liquid-treated silane, in the range of tested target DNA concentration going to 10 nM. Finally, the impedance and fluorescence response signals strongly depend on the types of target DNA molecules, demonstrating a high selectivity of the process on nanoporous SnO2 films.
Development of an Ultrasonic Airflow Measurement Device for Ducted Air
Authors: Raine Andrew , Aslam Nauman , Underwood Christopher , Danaher Sean
Published: May 2015

In this study, an in-duct ultrasonic airflow measurement device has been designed, developed and tested. The airflow measurement results for a small range of airflow velocities and temperatures show that the accuracy was better than 3.5% root mean square (RMS) when it was tested within a round or square duct compared to the in-line Venturi tube airflow meter used for reference. This proof of concept device has provided evidence that with further development it could be a low-cost alternative to pressure differential devices such as the orifice plate airflow meter for monitoring energy efficiency performance and reliability of ventilation systems. The design uses a number of techniques and design choices to provide solutions to lower the implementation cost of the device compared to traditional airflow meters. The design choices that were found to work well are the single sided transducer arrangement for a “V” shaped reflective path and the use of square wave transmitter pulses ending with the necessary 180° phase changed pulse train to suppress transducer ringing. The device is also designed so that it does not have to rely on high-speed analogue to digital converters (ADC) and intensive digital signal processing, so could be implemented using voltage comparators and low-cost microcontrollers.
Enantioselective Recognition of Chiral Carboxylic Acids by a β-Amino Acid and 1,10-Phenanthroline Based Chiral Fluorescent Sensor
Authors: Zhang Yonghong , Hu Fangzhi , Wang Bin , Zhang Xiaomei , Liu Chenjiang
Published: May 2015

A novel chiral 1,10-phenanthroline-based fluorescent sensor was designed and synthesized from optical active β-amino acids. It used 1,10-phenanthroline moiety as a fluorescent signaling site and binding site, with optically active β-amino acids as a chiral barrier site. Notably, the optically active β-amino acids were obtained by a Lewis base catalyzed hydrosilylation of β-enamino esters according to our former work. The chiral sensor has been used to conduct the enantioselective recognition of chiral mono and dicarboxylic acids derivatives. Using this fluorescent sensor, a moderate “turn-off” fluorescence-diminishment response towards enantiomer of tartaric acids, and proline was observed. It found that l-enantiomers quench the chiral fluorescence sensor more efficiently than d-enantiomers due to the absolute configuration of the β-amino acid.
Accuracy of a Custom Physical Activity and Knee Angle Measurement Sensor System for Patients with Neuromuscular Disorders and Gait Abnormalities
Authors: Feldhege Frank , Mau-Moeller Anett , Lindner Tobias , Hein Albert , Markschies Andreas , Zettl Uwe , Bader Rainer
Published: May 2015

Long-term assessment of ambulatory behavior and joint motion are valuable tools for the evaluation of therapy effectiveness in patients with neuromuscular disorders and gait abnormalities. Even though there are several tools available to quantify ambulatory behavior in a home environment, reliable measurement of joint motion is still limited to laboratory tests. The aim of this study was to develop and evaluate a novel inertial sensor system for ambulatory behavior and joint motion measurement in the everyday environment. An algorithm for behavior classification, step detection, and knee angle calculation was developed. The validation protocol consisted of simulated daily activities in a laboratory environment. The tests were performed with ten healthy subjects and eleven patients with multiple sclerosis. Activity classification showed comparable performance to commercially available activPAL sensors. Step detection with our sensor system was more accurate. The calculated flexion-extension angle of the knee joint showed a root mean square error of less than 5° compared with results obtained using an electro-mechanical goniometer. This new system combines ambulatory behavior assessment and knee angle measurement for long-term measurement periods in a home environment. The wearable sensor system demonstrated high validity for behavior classification and knee joint angle measurement in a laboratory setting.
Carbon Fiber Epoxy Composites for Both Strengthening and Health Monitoring of Structures
Authors: Salvado Rita , Lopes Catarina , Szojda Leszek , Araújo Pedro , Gorski Marcin , Velez Fernando , Castro-Gomes João , Krzywon Rafal
Published: May 2015

This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the “wet process”, which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.
Closed-loop conductance scanning tunneling spectroscopy: demonstrating the equivalence to the open-loop alternative
Authors: Hellenthal Chris , Sotthewes Kai , Siekman Martin H , Kooij E Stefan , Zandvliet Harold J W
Published: May 2015

We demonstrate the validity of using closed-loop z(V) conductance scanning tunneling spectroscopy (STS) measurements for the determination of the effective tunneling barrier by comparing them to more conventional open-loop I(z) measurements. Through the development of a numerical model, the individual contributions to the effective tunneling barrier present in these experiments, such as the work function and the presence of an image charge, are determined quantitatively. This opens up the possibility of determining tunneling barriers of both vacuum and molecular systems in an alternative and more detailed manner.
Design, synthesis and photochemical properties of the first examples of iminosugar clusters based on fluorescent cores
Authors: Lepage Mathieu L , Mirloup Antoine , Ripoll Manon , Stauffert Fabien , Bodlenner Anne , Ziessel Raymond , Compain Philippe
Published: May 2015

The synthesis and photophysical properties of the first examples of iminosugar clusters based on a BODIPY or a pyrene core are reported. The tri- and tetravalent systems designed as molecular probes and synthesized by way of Cu(I)-catalysed azide–alkyne cycloadditions are fluorescent analogues of potent pharmacological chaperones/correctors recently reported in the field of Gaucher disease and cystic fibrosis, two rare genetic diseases caused by protein misfolding.
CHARACTERIZATION OF PERMANENT DEFORMATION RESISTANCE OF PRECIPITATED CALCIUM CARBONATE MODIFIED ASPHALT MIXTURE
Authors: Moghadas Nejad Fereidoon , Azarhoosh Ali Reza , Hossein Hamedi Gholam , Azarhoosh Mohammad Javad
Published: May 2015

Rutting in asphalt pavements that appears as an indentation in the longitudinal direction continues to create problems for pavement agencies. This paper presents the results of the laboratory study on rutting susceptibility of asphalt mixtures containing Precipitated Calcium Carbonate (PCC) coated by a thin layer of a polymeric compound. To assess the impact of PCC on rutting properties of HMA, control mixtures (without PCC) and mixtures containing PCC were tested using dynamic creep and indirect tensile stiffness modulus tests. The HMA mixtures containing 0%, 5%, 10%, and 15% of PCC were prepared. In this paper, it is shown that the use of PCC can decrease the rutting potential of asphalt mixes. According to the results obtained in this study; using a 5% PCC in HMA is acceptable for heavy traffic volume roads especially in tropical regions.
BRIDGE INSPECTION PRACTICES USING NON-DESTRUCTIVE TESTING METHODS
Authors: Lee Sangwook , Kalos Nikolas
Published: May 2015

Non-Destructive Testing (NDT) methods have been developed and employed as a means of rapid and effective structural inspection. Despite the various kinds of NDT methods developed for bridge inspection, not much study has been performed on their usage and effectiveness at a practical level. This paper presents an evaluation of NDT methods to identify how they are implemented in state agencies in the U.S. The findings and analysis presented herein were based on the results obtained from a survey questionnaire, targeted at Departments of Transportation (DOTs) in all U.S. states and territories. The survey questionnaire was initiated to clarify multiple issues regarding NDT implementation, such as identifying the types of inspection that involve NDT methods, bridge components that are most likely to be inspected with NDT, effective methods of inspecting concrete or steel structures, and so on. A total of 40 state agencies participated in the survey processing, and the major findings obtained from the states are illustrated and explained in detail in this paper. In addition, bridge defects that are hard to detect in the course of inspection and current research efforts to develop novel NDT methods were investigated.
THEORETICAL MODEL FOR DOUBLE-SKINNED CONCRETE-FILLEDSTEEL-TUBULAR COLUMNS WITH EXTERNAL CONFINEMENT
Authors: Dong Chun Xiao , Ming Ho Johnny Ching
Published: May 2015

Recent advances in the production of super-fine cement and filler technology has made the production of high-strength concrete (HSC) of 120 MPa practicable in the industry. Nonetheless, the application of such HSC in real construction is still limited. One of the reasons that inhibits the use of HSC is the brittleness, which causes HSC structures to fail explosively if the concrete confinement is not adequate. The traditional method of installing transverse steel as confinement is not feasible in HSC structures, as the steel will be too congested to ensure proper concrete placing. To overcome the problem, double-skinned high-strength concrete-filled-steel-tubular (HSCFST) columns has been advocated, which could provide large, continuous and uniform confinement to HSC. However, a major shortcoming of the double-skinned HSCFST columns is the imperfect interface bonding that occurs at the elastic stage that reduces the elastic strength and stiffness of columns. To improve the situation, the authors have verified previously that using external steel rings on the outer steel tube can successfully restrict the dilation of HSCFST columns and thus restore an intact interface bonding condition. As a continued study, the authors will in this paper develop a theoretical model for predicting the uni-axial load-carrying capacity of doubled-skinned HSCFST columns.
DETERMINANTS OF TRANSACTION COSTS IN CONSTRUCTION PROJECTS
Authors: Li Huimin , Arditi David , Wang Zhuofu
Published: May 2015

Transaction costs occur when a good or service is transferred across a technologically separable interface, and include the costs of drafting, negotiating and enforcing an agreement, and also the costs of governance and bonding to secure commitments. In the complex and high risk environment of a construction project, questionable decisions can be made in the planning and design phase, and disagreements, conflicts, disputes, change orders, and claims can occur in the construction phase. These problems contribute to an increase in transaction costs. Transaction costs at the pre-contract phase of a project are different from the transaction costs at the post-contract phase. However, there is no consensus on a standard definition of transaction costs in construction projects. In this study, a detailed literature review focusing on transaction costs in construction project management is presented. The factors that affect transaction costs are identified and categorized under the headings of the owner’s and contractor’s roles in the transaction, project management efficiency, and the characteristics of the transaction environment.
ERRATUM
Authors: Yu Jung-Ho , Jeon Me-Yeon , Wan Kim Tae
Published: May 2015

Erratum." Journal of Civil Engineering and Management, 21(5), p. 677
Prélèvements fiscaux et prestations sociales en Belgique : l’impact de vingt années de réformes
Authors: Decoster André , Perelman Sergio , Vandelannoote Dieter , Vanheukelom Toon , Verbist Gerlinde
Published: May 2015

Au cours des vingt dernières années la Belgique a connu une série importante de réformes aussi bien au niveau des prélèvements fiscaux, y compris les cotisations sociales personnelles, que des transferts sociaux. Ces réformes ont joué un rôle déterminant sur l’offre de travail et sur l’évolution du revenu disponible des ménages. Cet article analyse simultanément l’ensemble des changements intervenus dans l’impôt sur le revenu des personnes, les cotisations sociales et les prestations de sécurité sociale sur la période 1992-2012. Afin de prendre en compte l’hétérogénéité des ménages, on simule les effets des réformes à l’aide du modèle de micro-simulation Mefisto-Euromod et des données EU-SILC. Les résultats montrent qu’au cours de cette période, les réformes ont été favorables aux catégories les plus pauvres de la population et que, de manière générale, les inégalités de revenu ont été réduites. Cependant ces avancées ont eu comme contrepartie l’augmentation du coût marginal des fonds publics. Le bonus à l’emploi a eu un effet favorable sur le taux d’imposition implicite affectant la participation au marché du travail ; en revanche, l’augmentation des revenus de remplacement, en particulier des allocations de chômage, a eu l’effet inverse.
Equité du système de santé belge
Authors: Schokkaert Erik , Van de Voorde Carine
Published: May 2015

Nous décrivons dans les grandes lignes la performance globale du système de santé belge. Nous livrons une vision élargie de l’équité dans le domaine de la santé qui porte à conclure qu’il faudrait se centrer sur les effets de la santé/des soins de santé sur le bien-être individuel. Il s’agit de la manière la plus appropriée de rendre compte du phénomène de privation cumulative et de rapprocher divers domaines d’action. Nous montrons qu’il est possible de concrétiser cet axe de recherche. A court terme, il convient d’adopter une vision plus étroite et d’examiner l’accessibilité financière du système de soins de santé puisqu’il s’agit d’une condition indispensable (quoiqu’insuffisante) à l’équité. Nous soutenons que le système du maximum à facturer constitue une protection satisfaisante pour les tickets modérateurs, bien que sa structure puisse être reconsidérée. Le manque d’informations à propos des effets des suppléments sur l’équité et la couverture insuffisante des frais de soins non médicaux font partie des problèmes qui revêtent une plus grande importance. Nous aborderons pour terminer les éléments de preuve concernant le report de soins de santé pour raisons financières.
Un concept d’échelles d’équivalence du temps de travail pour l’évaluation de l’impôt sur le revenu
Authors: Maniquet François , Neumann Dirk
Published: May 2015

Nous proposons une méthode pour évaluer la capacité des systèmes de taxation du revenu à diminuer la pauvreté, lorsque celle-ci est définie en cohérence avec une notion de niveau de vie issue de l’éthique de la responsabilité. Selon cette éthique, toutes les inégalités ne sont pas injustes. Nous supposons que les inégalités de revenu dues aux inégalités de temps de travail ne sont pas injustes. Pour résoudre le problème de la comparaison entre ménages de tailles différentes, nous introduisons un concept d’échelle d’équivalence de temps de travail. Nous appliquons la méthode à l’évaluation du système fiscal belge.
Typification of Heliotropium and Tournefortia (Heliotropiaceae) species described by Ruiz and Pavón
Authors: Luebert Federico , Hilger Hartmut H.
Published: May 2015

Lectotypes are designated here for 14 names proposed by Ruiz and Pavón in “Flora peruviana, et chilensis” (1799) that were either described or are currently recognized as members of the genera Heliotropium or Tournefortia (Heliotropiaceae): Heliotropium corymbosum, H. incanum, H. lanceolatum, H. microcalyx, H. microstachyum, H. oppositifolium, H. pilosum, H. synzystachyum, Lithospermum aggregatum, Tournefortia angustiflora, T. longifolia, T. polystachya, T. undulata, T. virgata. Currently accepted names and comments on typifications and taxonomic affinities are also provided.
Pollen: ovule ratio and its relationship with other reproductive traits in some Passiflora species (Passifloraceae)
Authors: Amela García María Teresa , Miguez María Belén , Gottsberger Gerhard
Published: May 2015

The pollen/ovule (P/O) ratio has been used as predictor of the reproductive system of angiosperms (lowest P/O values correspond to obligate autogamous species while the highest correlate with obligate xenogamous species) but it does not keep for all the taxa. The relation of P/O index with pollen and stigma size, flower diameter, pollen vitality, stigmatic area/pollen-bearing area of the pollinators ratio (SA/PBA), taxonomy and breeding system was analyzed in four Passiflora species with different degree of compatibility, pollination system and taxonomic placement. P/O of the self-compatible species (with shorter anthesis, scarce pollinator visits or minor longevity) was lower than P/O of the self-incompatible ones. The P/O values of the outcrossers could be related with the highly efficient pollination performed by the frequently visiting Xylocopa species; these bees transport Passiflora pollen in a usually monospecific mass on the thorax, resembling grouped pollen dispersal. All the taxa exhibited pollen with unimodal size and high vitality, except for P. misera, in which pollen size was bimodal, with similar quantities of grains in both classes, the large being more vital than the small ones. Correlations of P/O were positive with flower size, negative with stigma area/pollen-bearing area of the pollinator, null with stigma area and not significant with pollen size. The P/O ratio did not reflect taxonomic affinities; this index and the breeding system were more related with pollinator type, anthesis, flower size and SA/PBA than with pollen grain or stigma size.
Abrasion-Corrosion of Thermal Spray Coatings
Authors: Wood Robert J. K. , Thakare Mandar R.
Published: May 2015

WC-based thermal-spray and High Velocity Oxy-Fuel (HVOF) coatings are extensively used in a wide range of applications ranging from downhole drilling tools to gas turbine engines. WC-based thermal spray coatings offer improved wear resistance as a result of hard phases dispersed in binder-rich regions. However, the presence of hard and soft phases within the coating can also lead to the formation of micro-galvanic couplings in aqueous environments leading to some reduction in combined wear-corrosion resistance. Furthermore, the coating also responds differently to change in mechanical loading conditions. This chapter examines the wear-corrosion performance of thermal spray coatings in a range of wear, electrochemical, and wear-corrosion tests under varying contact conditions to develop models and establish relationships between wear mechanisms, wear rates, and environmental factors such as pH and applied load.
Slurry Erosion Behavior of Thermal Spray Coatings
Authors: Grewal Harpreet Singh , Singh Harpreet
Published: May 2015

Slurry erosion is a degrading phenomenon usually observed in machineries dealing with particle-laden fluid such as hydro power plants, ship propellers, pump impellers, valves, and connecting pipes. The low erosion resistance of commonly employed structural materials prompts the use of different surface modification techniques. Among several types of surface modification techniques, thermal spraying has achieved a significant recognition worldwide due to its versatile nature. In this chapter, slurry erosion behavior of thermal sprayed coatings has been discussed with special emphasis on the contribution of different coating related parameter. It has been observed that microstructure play an important role in determining the slurry erosion performance of thermal spray coatings. Different microstructural features such as splat boundaries, pores, un-melted particles, and cracks are detrimental for the thermal spray coatings exposed to erosive environment. A parameter useful for identification of primary erosion mechanism for thermal sprayed coatings is also discussed.
Decreasing Wear of Large Vertical Axis Wind Turbines by Employing a Multi-Level Turbine Concept
Authors: Wiśniewski Jan H.
Published: May 2015

The chapter focuses on describing the author's own multi-level vertical axis wind turbine concept, putting emphasis on its specific features, the scope of conducted analyses, as well as general knowledge important to wind industry specialists, other people with an interest in wind energy, and engineers aspiring to achieve innovative results without needlessly complicating their design. Current results show a reduction of the maximum bending moment during a rotation at the bottom of a two level turbine of up to 19.7% after optimisation; at the same time an optimised turbine can achieve a reduction of maximum moment jump during a rotation at the bottom of a turbine of up to 73.4%. Further studies are currently being conducted, as both the study presented in this chapter and its continuations might have a definitive influence on the future development of the wind-energy sector.
Electricity Production from Small-Scale Photovoltaics in Urban Areas
Authors: Psomopoulos Constantinos S. , Ioannidis George Ch. , Kaminaris Stavros D.
Published: May 2015

The interest in solar photovoltaic energy is growing worldwide. Today, more than 40GW of photovoltaics have been installed all over the world. Since the 1970s, the PV system price is continuously dropping. This price drop and the adaptation of feed-in tariffs at governmental or utility scale have encouraged worldwide application of small-scale photovoltaic systems. The objective of this chapter is to present the potential for electricity production focusing mainly on the benefits of small-scale installations in urban areas, along with the growth of the global photovoltaics market. The types of installation alternatives are described but the focus is on the rooftop installations due to their simplicity and relatively low cost for urban areas. Electricity production data are presented together with their technical characteristics. Furthermore, analysis of the cost reduction is attempted and the benefits gained from the implementation of small-scale systems are also presented, demonstrating the sustainability role they will play.
Mathematical and Stochastic Models for Reliability in Repairable Industrial Physical Assets
Authors: Gunckel Pablo A. Viveros , Márquez Adolfo Crespo , Kristjanpoller Fredy A. , Tapia Rene W. , González-Prida Vicente
Published: May 2015

Generally, assets present a varied behaviour in their life cycle, which is related directly to the use given and consequently related to the technical assistance traditionally known as maintenance or maintenance policies. It can be of a diverse nature: perfect, minimum, imperfect, over-perfect, and destructive as appropriate. This feature requires the application of advanced techniques in order to model the behaviour of assets life, adapting ideally to each reality of use and wear out. In this chapter, the stochastic models PRP, NHPP, and GRP are explained with their conceptual, mathematic, and stochastic development. For each model, the conceptualization, parameterizing, and stochastic simulation are analysed. Additionally, complementing the analysis and resolution pattern, these models are concluded with a numeric application that allows one to show step by step the mathematic and stochastic development as appropriate.
Low Carbon Footprint
Authors: Shaharudin Muhammad Shabir , Fernando Yudi
Published: May 2015

Malaysia has committed to a 40% reduction of carbon emissions by 2020. The government has encouraged industry, society, and non-government organizations to work together to achieve this objective. The government has provided incentives through several energy programmes such as energy efficiency, renewable energy, green technology, and green building. One key area that has been targeted is logistics and supply chain, which has been contributing to high carbon emissions in manufacturing industries. Scholars and practitioners have only recently begun to pay attention to creating a low carbon supply chain. Furthermore, Small Medium Enterprises (SMEs) have faced several challenges in adopting low carbon activities. SMEs are unable to take the advantage of energy initiatives because of a lack of knowledge, a shortage of funds, and inadequate facilities. Almost 90% of firms are in the service industry working with large manufacturing firms and some SMEs working in manufacturing industry are working closely with their supply chain networks; achieving low carbon targets is hampered by the readiness of the manufacturing itself. This chapter discusses the challenges and future agenda of creating low carbon supply chains in manufacturing in Malaysia. Possible solutions are provided at the end of the chapter.
ELearning for Persons with Visual Disabilities
Authors: Wambua Ruth N. , Oboko Robert
Published: May 2015

This chapter discusses an eLearning platform that is usable by persons with low vision. To start with, such a platform is achieved by incorporating technological advances such as: use of text with the highest possible contrast; use of varying font size; among other customized Human Computer Interaction (HCI) effects. Moreover, use of complicated, decorative or cursive fonts should be avoided, as well as italic text and capital letters, which can be difficult for users with reading impairments. In summary, this chapter supports the fact that eLearning is possible for persons with low vision, provided that all the necessary technological advances have been considered.