bluuebunny/crossref_metadata_2025 huggingface dataset:
Lamb Wave Based Monitoring of Fatigue Crack Growth Using Principal Component Analysis
Authors: Lu Ye , Lu Ming Yu , Ye Lin , Wang Dong , Zhou Li Min , Su Zhong Qing
Published: June 2013

Fatigue crack growth in metallic plates was monitored using Lamb waves which were generated and captured by surface-mounted piezoelectric wafers in a pitch-catch configuration. Instead of directly pinpointing signal segments to quantify wave scattering caused by the existence of crack damage and related severity, principal component analysis (PCA), as an efficient approach for information compression and classification, was undertaken to distinguish different structural conditions due to fatigue crack growth. For this purpose, a variety of statistical parameters in the time domain as damage indices were extracted from the wave signals. A series of contaminated counterparts with different signal-to-noise ratios were also simulated to increase the statistical size of the data set. It was concluded that PCA is capable of reducing the dimensions of a complex set of original data, whose information can be represented and highlighted by the first few principal components. With the assistance of PCA, the different structural conditions attributable to crack growth can be classified.
Damage Assessment Methodology for Nonstructural Components with Inspection Robot
Authors: Nitta Yoshihiro , Nishitani Akira , Iwasaki Atusmi , Watakabe Morimasa , Inai Shinsuke , Ohdomari Iwao
Published: June 2013

This paper proposes a damage assessment methodology for the non-structural elements, especially ceiling elements of a building, utilizing an inspection robot. The developed inspection robot equipped with a wireless camera and data processing function has a capability of providing valuable information for the repair and maintenance decision making of a damaged structure. The inspection robots will be able to estimate the damage condition without any process of engineers on-site-inspection involved. The robots also can gather the static data of the nonstructural elements from the sensor, which are distributed on the nonstructural elements. To demonstrate the effectiveness of the inspection robot, the robot is utilized to estimate the ceiling of a real structure damaged by the 2011 off the Pacific coast of Tohoku Earthquake. And conceptual experiment is also conducted for the purpose of evaluating the proposed damage assessment methodology in cooperation with the smart sensor and the inspection robot. The proposed methodology will provide useful information to the maintenance and repair planning of a damaged structure.
An Enhanced Experimental Facility for Durability and Performance Characterisation of Piezoelectric Transducers for Structural Health Monitoring
Authors: Jung George , van der Velden Stephen , Tsoi Kelly , Rajic Nik
Published: June 2013

With any structural health monitoring (SHM) system, verification of the health of the sensing elements is essential in ensuring confidence in the measurements furnished by the system. In particular, SHM systems utilised for structural hot spot monitoring applications will conceivably require transducers to operate reliably after sustained exposure to severe mechanical loading. Consequently, a good understanding of the long term mechanical durability performance of structurally integrated piezoelectric transducers is vital when designing and implementing robust SHM systems.
An experimental facility has been developed at the Australian Defence Science and Technology Organisation (DSTO) capable of performing an autonomous long-term mechanical durability test on piezoceramic transducers. The Autonomous Mechanical Durability Experimentation and Analysis System (AMeDEAS) incorporates a general purpose data acquisition program controlling up to three 8-channel relay multiplexers and two instruments. AMeDEAS is highly flexible, allowing user-specified channel configurations and automatic interrogation of selected instruments. The system also interfaces with the uni-axial mechanical testing machine to provide control of the load sequence allowing transducer elements to be interrogated under stable load-free conditions after being subject to a predefined loading regime.
AMeDEAS was used to investigate the fatigue characteristics of a low-profile layered piezoceramic transducer package developed by DSTO. A total of 16 transducers were tested under tension-dominated cyclic loading with peak-to-peak strain amplitude increasing from 400 με to a maximum of 3000 με, with periodic acoustic transduction efficiency and electromechanical impedance measurements taken throughout the test. This paper details the AMeDEAS and includes preliminary results which confirm the efficacy of the new facility.
A Framework for Reliability Assessment of an In-Service Bridge Using Structural Health Monitoring Data
Authors: Chen Xing Hua , Omenzetter Piotr
Published: June 2013

Because of the critical role that bridges play in land transport networks and broader economy, the assessment of existing bridges is gradually becoming a global concern. Structural health monitoring (SHM) systems have been installed on many bridges to provide data for the evaluation of bridge performance and safety. The challenge for bridge engineers is now to make use of the data and convert them into usable information and knowledge. Integrating SHM data with reliability analysis procedures offers a useful and practical methodology for bridge assessment since reliability is an important performance index and reliability-based procedures have the capability of accommodating uncertainties in structural models, responses, loads and monitoring data. In this paper, an approach for integrating SHM data in a reliability assessment framework is proposed. The reliability of the bridge is quantified by incorporating SHM information in the resistance, load and structural models. Advanced modeling tools and techniques, such as finite element analysis, finite model updating and Bayesian updating, are used for the reliability computations. Data from the SHM system installed on the Newmarket Viaduct, a newly constructed, 12-span, post-tensioned box girder bridge erected by the balanced cantilever method in Auckland, New Zealand, are also presented in this paper and used to explain the proposed framework.
Acoustic Emission for Tank Bottom Monitoring
Authors: Martin Gary
Published: June 2013

Acoustic Emission (AE) monitoring is an effective tool for prioritising more conventional non-destructive inspections of above ground tanks, either process or storage vessels. Results obtained from AE monitoring may be assessed against an existing data bank permitting plant management to prioritise maintenance to tanks with high active corrosion rates or leaks. AE results may be used to extend inspection periods of tanks without leaks or active corrosion.This paper briefly covers the theory of AE leak detection and corrosion monitoring including some background research into the difference between AE from corrosion and leaks. It looks at the equipment used and provides a summary of tank test results conducted by ATTAR and other overseas organisations as well as reviewing AE tank inspection economics.
Multiphysics Modelling and Experimental Validation of a Bi-Axial Magnetoelectric Vibration Energy Harvester
Authors: McLeod Joshua E. , Moss Scott D.
Published: June 2013

This paper reports on the multiphysics modelling of a bi-axial vibration energy harvesting (VEH) approach, with experimental validation of the model predictions. The authors have developed a harvester able to generate voltage under bi-axial vibrations. The harvesting approach is based on a magnetoelectric (ME) transducer that is positioned between a fixed magnet and oscillating ball bearing, which steers a changing magnetic field through the transducer to generate a voltage. The transducer combines magnetostrictive and piezoelectric properties to convert magnetic potential into electrical energy. Analytical modelling of this phenomenon is difficult due to the highly coupled nature of this interaction, so Comsol multiphysics software is used to make predictions of output using the finite element method (FEM). A peak open-circuit harvester voltage of 39.4 V is predicted for a ball bearing oscillating with 4.5 mm amplitude, agreeing reasonably well with measured harvester voltage of approximately 35 V. The modelling is applied to a two-dimensional representation of the system, which is shown to be sufficient for a basic understanding of the highly coupled nature of interactions, and a basis for optimising the magnetoelectric vibration energy harvesting approach.
Interaction of High Frequency Lamb Waves with Surface-Mount Sensor Adhesives
Authors: Norman Patrick , Davis Claire , Rosalie Cédric , Rajic Nik
Published: June 2013

The application of Lamb waves to damage and/or defect detection in structures is typicallyconfined to lower frequencies in regimes where only the lower order modes propagate in order to simplifyinterpretation of the scattered wave-fields. Operation at higher frequencies offers the potentialto extend the sensitivity and diagnostic capability of this technique, however there are technical challengesassociated with the measurement and interpretation of this data. Recent work by the authorshas demonstrated the ability of fibre Bragg gratings (FBGs) to measure wave-fields at frequencies inexcess of 2 MHz [1]. However, when this work was extended to other thinner plate specimens it wasfound that at these higher frequencies, the cyanoacrylate adhesive (M-Bond 200) used to attach theFBG sensors to the plate was significantly affecting the propagation of the waves. Laser vibrometrywas used to characterise the wave-field in the region surrounding the adhesive and it was found that theself-adhesive retro-reflective tape applied to aid with this measurement was also affecting the wavefieldin the higher frequency regime. This paper reports on an experimental study into the influence ofboth of these materials on the propagating wave-field. Three different lengths of retro-reflective tapewere placed in the path of Lamb waves propagating in an aluminium plate and laser vibrometry wasused to measure the wave-field upstream and downstream of the tape for a range of different excitationfrequencies. The same experiment was conducted using small footprint cyanoacrylate film samplesof different thickness. The results show that both of these surface-mount materials attenuate, diffractand scatter the incoming waves as well as introducing a phase lag. The degree of influence of thesurface layer appears to be a function of its material properties, the frequency of the incoming waveand the thickness and footprint of the surface layer relative to the base material thickness. Althoughfurther work is required to characterise the relative influence of each of these variables, investigationsto date show that for the measurement of Lamb Waves on thin structures, careful considerationshould be given to the thickness and footprint of the adhesive layer and sensor, particularly in the highfrequency regime, so as to minimise their effect on the measurement.
Thermoelastic Stress Analysis - Emerging Opportunities in Structural Health Monitoring
Authors: Rajic Nik , Galea Steve C. , Rowlands David
Published: June 2013

The emergence recently of a thermoelastic stress analysis (TSA) capability exploiting low-cost, compact and rugged microbolometer detector technology provides a significant opportunity topromote a broader use of this powerful non-contact full-field stress analysis technique. An area whereit has considerable and hitherto unexplored potential is in in-situ structural health monitoring (SHM).The present paper outlines the case for a nexus between SHMand TSA in this new form. It is proposedthat the approach should yield diagnostic and prognostic capabilities surpassing those of some existingSHM modalities. An F/A-18 centre-fuselage full-scale structural fatigue test is employed as a casestudy to illustrate the practical feasibility of the approach and to underscore some of its potential.Although the case study focuses on an aircraft structure, the concept has potential application to awide variety of different engineering assets across the aerospace, civil and maritime sectors.
Laser Lock-In Thermography for Fatigue Crack Detection
Authors: An Yun Kyu , Kim Ji Min , Sohn Hoon
Published: June 2013

This study proposes a new nondestructive evaluation methodology named laser lock-in thermography (LLT) for fatigue crack detection. LLT utilizes a high power continuous wave (CW) laser as a heat generation source for lock-in thermography instead of commonly used flash and halogen lamps. The advantages of the proposed LLT method are that (1) the laser heat source can be positioned at an extended distance from a target structure thank to the directionality and low energy loss of the laser source, (2) thermal image degradation due to surrounding temperature disturbances can be minimized because of high temperature gradient generated by the laser source and (3) a large target surface can be inspected using a scanning laser heat source. The developed LLT system is composed of a modulated high power CW laser, galvanometer and infrared camera. Then, a holder exponent-based data processing algorithm is proposed for intuitive damage evaluation. The developed LLT is employed to detect a micro fatigue crack in a metal plate. The test result confirms that 5 μm (or smaller) fatigue crack in a dog-bone shape aluminum plate with a dimension of 400 x 140 x 3 mm3 can be detected.
In Situ Blade Deflection Monitoring of a Wind Turbine Using a Wireless Laser Displacement Sensor Device within the Tower
Authors: Giri Paritosh , Lee Jung Ryul
Published: June 2013

With commercially viable global wind power potential, wind energy penetration is further expected to rise, as will the related problems. One issue is the collision of wind turbine blades with the tower during operation. Structured health monitoring is required to improve operational safety, minimize the risk of sudden failure or total breakdown, ensure reliable power generation, and reduce wind turbine life cycle costs. Large numbers of sensors such as fiber Bragg grating and piezoelectric devices have been attached to the structure, a design that is uneconomical and impractical for use in large wind turbines. This study proposes a single laser displacement sensor (LDS) system in which all of the rotating blades could be cost-effectively evaluated. Contrary to the approach of blade sensor installation, the LDS system is installed in the tower to enable noncontact blade displacement monitoring. The concept of a noncontact sensor and actuator and their energy delivery device installation in the tower will enable various approaches for wind turbine structural health monitoring. Blade bolt loosening causes deflection in the affected blade. Similarly, nacelle tilt or mass loss damage in the blade will result in changes in blade deflection, but the proposed system can identify such problems with ease. With the need of more energy, the sizes of wind blades are getting bigger and bigger. Due to the large size of wind turbine, nowadays wind turbines are installed very high above the ground or water level. It is impractical to monitor the results from LDS through wired connection in these cases. Hence, the wired connection of LDS to base (monitoring) station must be replaced by a wireless solution. This wireless solution is achieved using Zigbee technology. Zigbee operates in the industrial, scientific and medical (ISM) radio bands, typically 2.4 GHz, 915 MHz and 868 MHz. The output from the LDS is fed to the microcontroller which acts as an analog to digital converter. The output from the microcontroller is connected to the Zigbee transceiver module, which transmits the data and at the other end, the zigbee reads the data and displays on the PC from where user can monitor the condition of wind blades.
Guided Wavefield Images Filtering for Damage Localization
Authors: Ostachowicz Wieslaw , Kudela Pawel , Radzienski Maciej
Published: June 2013

The goal of this paper is to develop a new method of filtering and processing of guided wavefield images acquired by the laser vibrometers. The concept is tested on both numerical results and experimental data obtained from measurements of aluminium alloy plate which notch cuts. Results were compared with RMS based maps for different excitation frequencies.
Preparation of Cellulose Stearate and Cellulose Acetate Stearate in 1-Butyl-3-Methylimidazolium Chloride
Authors: Tarasova Elvira , Šumigin Dmitri , Kudrjašova M. , Krumme A.
Published: June 2013

Cellulose stearates were prepared in a 1-butyl-3-metylimidazolium chloride ionic liquid. The addition of base pyridine as well as catalyst Tin octoate sufficiently increases the degree of hydroxyl group substitution. The new path for preparation of cellulose mixed esters, namely cellulose acetate stearate (CAS), is performed. The 1H NMR data confirmed the structure of obtained mono- and mix- cellulose esters.
Improvement of Paper Hydrophobic Properties by Using Biodegradable Natural Polymer – Chitosan
Authors: Vikele Laura , Treimanis Arnis , Laka Marianna
Published: June 2013

The aim of the present study was to improve the paper handsheets parameters by adding biodegradable natural polymer – chitosan. The addition of chitosan in the amount of 2-4% improved tensile strength of the handsheets by up to 20% in dry condition and by up 5 times in wet state. Addition of chitosan increases the hydrophobic properties of paper as it was revealed by contact angle and water penetration dynamic measurements.
Electrochemical Properties of Advanced Anodes for Lithium-Ion Batteries Based on Carboxymethylcellulose as Binder
Authors: Khomenko Volodymyr , Barsukov Viacheslav , Senyk Ilona
Published: June 2013

Electrochemical properties and possibilities of manufacturing the anodes based on water-soluble binders such as carboxymethylcellulose (CMC) have been investigated in order to create prerequisites for development of “green” technologies for recyclability of LIBs components. In this work an advanced anode was designed. A kind of nanosized carbon coated Si composite was synthesized. The charge/discharge test reveals that the advanced anode shows a reversible capacity of 600 mAh/g. The improved performance was ascribed to the carbon shell of Si and CMC binder. The binder CMC buffers the expansion of the Si and the improved electric contact between the active material and copper current collector.
Three Different Approaches for Polyol Synthesis from Rapeseed Oil
Authors: Kirpluks Mikelis , Cabulis Ugis , Kurańska Maria , Prociak Aleksander
Published: June 2013

Three different kinds of polyols from rapeseed oil were synthesised and characterized during this study. Afterwards, using these polyols rigid polyurethane foams were produced, which are used as thermal insulation material in construction industry and in production of refrigerators. Polyols from rapeseed oil were synthesised by epoxidation, transamidization and transesterification methods. One rapeseed oil based polyol was synthesized by partial epoxidation of the double bonds in fatty acid chains and overall opening oxirane rings by using diethylene glycol. Other two methods transamidization and transesterification of ester bonds of triglyceride were carried out using diethanolamine and triethanolamine respectively. To use these polyols for production of polyurethane foams, hydroxyl value, acid value, water content, viscosity and density of polyols were determinated. The functionality of obtained polyols was calculated on the base of number-average molecular weight and hydroxyl value. After laboratory trials a pilot scale production of the rapeseed oil polyols was carried out in 50 L reactor. From synthesized polyols rigid polyurethane foam samples were produced in laboratory scale and also in semi industrial scale, using industrial high pressure spraying equipment machine. Technological parameters, density and closed cell content were determined for obtained polyurethane foams.
Magnetic Annealing on GNO Electrical Steel Fe-3.25% Si
Authors: Castello-Branco Gilberto Alexandre , Muller Jennifer Nadine , Bacaltchuk Cristiane Maria Basto
Published: June 2013

Grain non-oriented electrical steel has its main application in electrical motors and its microstructure significantly influences their efficiency. The objective of this work was to investigate whether or not magnetic field applied during annealing process affects grain growth and the development of important texture components leading to an improvement of the magnetic properties. GNO Fe-3.25%Si 75% cold rolled specimens were annealed inside magnetic field with strength of 17 T at the temperature of 800°C for 3, 10 and 30 minutes. Results of average grain size after magnetic annealing showed a microstructure formed by small grains and a few very large grains. Magnetic field did not increase orientation density of {100} oriented grains and Goss grains but was able to increase density of θ fiber and decrease the density of γ fiber.
Shape Memory Alloy Helical Springs Performance: Modeling and Experimental Analysis
Authors: de Aguiar Ricardo Alexandre Amar , de Castro Leão Neto Waldyr Cardoso , Savi Marcelo Amorim , Calas Lopes Pacheco Pedro Manuel
Published: June 2013

Shape memory alloys (SMAs) are metallic materials that have the capability to recover its original shape eliminating residual strains when subjected to adequate thermal process. This behavior is related to phase transformation induced either by stress or by. During the phase transformation process of an SMA component, large loads and/or displacements can be generated in a relatively short period of time making this component an interesting mechanical actuator. Because of such remarkable properties, SMAs have found a number of applications in different areas. The present contribution deals with the modeling, simulation and experimental analysis of SMA helical springs. Basically, it is assumed a one-dimensional constitutive model to describe its thermomechanical shear behavior and, afterwards, helical springs are modeled by considering classical approach. SMA helical spring thermomechanical behavior is investigated through experimental tests performed at different loads. Numerical results show that the model is in close agreement with experimental data. Since the thermal process has an essential importance in the performance of an SMA actuator, different cooling medium conditions are investigated, evaluating the actuators performance.
Corrosion Fatigue Behavior of Flexible Pipe Tensile Armor Wires in a CO2 Environment
Authors: Santos Fabio , Pires Fabio , Clements Richard , Clevelario Judimar , Sheldrake Terry , de Souza Luís Felipe Guimarães , Kenedi Paulo Pedro
Published: June 2013

The new offshore areas being explored in Brazil presents higher concentration of CO2 compared with most existing offshore fields. The presence of these more aggressive environments has led to the development of new technologies. Due to the construction characteristics of flexible pipes, any increase in CO2 concentration in the conveyed fluid will, in turn, increase the CO2 concentration in the pipe annulus, subjecting the metallic armor layers to a more aggressive environment. Evaluation of the CO2 effects of corrosion fatigue behavior in tensile armor wires is therefore of vital importance. A comprehensive corrosion fatigue experiment for tensile armor wires in environments up to 10 bar of CO2, has been established and the experimental results have shown a fatigue life reduction in the tensile amour wires due to higher levels of CO2.
Monitoring Fatigue Crack Growth in Fracture Mechanics Specimens with Piezoelectric Sensors
Authors: Gama Antonio Lopes , Morikawa Sergio Ricardo Kokay
Published: June 2013

This paper presents the results of an experimental study on the application of piezoelectric dynamic strain sensors for monitoring the crack growth in fracture mechanics specimens. The performance of the piezoelectric sensors was assessed through fatigue crack propagation tests in three point bend (TPB) specimens and compact tension (CT) specimens. Piezoelectric sensors of lead zirconate titanate (PZT) were placed close to the crack edge of TPB specimens and piezoelectric polyvinilidene fluoride polymer (PVDF) was bonded to the back face of CT specimens. The piezoelectric sensors detect the crack growth by monitoring changes in the dynamic strain field of the specimen. In its simplest mode, the piezoelectric sensors behave like dynamic strain gages, with the main advantage of having a high sensitivity which allows detection of lower strain levels and lower increase in crack length.
Myeloid-Derived Suppressor Cells Play Crucial Roles in the Regulation of Mouse Collagen-Induced Arthritis
Authors: Fujii Wataru , Ashihara Eishi , Hirai Hideyo , Nagahara Hidetake , Kajitani Naoko , Fujioka Kazuki , Murakami Ken , Seno Takahiro , Yamamoto Aihiro , Ishino Hidetaka , Kohno Masataka , Maekawa Taira , Kawahito Yutaka
Published: June 2013

Myeloid-derived suppressor cells (MDSCs) are of myeloid origin and are able to suppress T cell responses. The role of MDSCs in autoimmune diseases remains controversial, and little is known about the function of MDSCs in autoimmune arthritis. In this study, we clarify that MDSCs play crucial roles in the regulation of proinflammatory immune response in a collagen-induced arthritis (CIA) mouse model. MDSCs accumulated in the spleens of mice with CIA when arthritis severity peaked. These MDSCs inhibited the proliferation of CD4+ T cells and their differentiation into Th17 cells in vitro. Moreover, MDSCs inhibited the production of IFN-γ, IL-2, TNF-α, and IL-6 by CD4+ T cells in vitro, whereas they promoted the production of IL-10. Adoptive transfer of MDSCs reduced the severity of CIA in vivo, which was accompanied by a decrease in the number of CD4+ T cells and Th17 cells in the draining lymph nodes. However, depletion of MDSCs abrogated the spontaneous improvement of CIA. In conclusion, MDSCs in CIA suppress the progression of CIA by inhibiting the proinflammatory immune response of CD4+ T cells. These observations suggest that MDSCs play crucial roles in the regulation of autoimmune arthritis, which could be exploited in new cell-based therapies for human rheumatoid arthritis.
The Effectiveness of Neighborhood Watch
Authors: Bennett Trevor , Holloway Katy , Farrington David
Published: June 2013

The primary aim of this Campbell systematic review is to assess the effectiveness of neighborhood watch in reducing crime. The narrative review was based on 19 studies (covering 43 evaluations) and the meta‐analysis was based on 12 studies (covering 18 evaluations). The data used included police‐recorded crimes and self‐reported victimizations.

This review concludes that neighborhood watch is associated with a reduction in crime.

Background

Neighborhood watch (also known as block watch, apartment watch, home watch and community watch) grew out of a movement in the US during the late 1960s that promoted greater involvement of citizens in the prevention of crime. Since then, interest in neighborhood watch has grown considerably and recent estimates suggest that over a quarter of the UK population and over forty per cent of the US population live in areas covered by neighborhood watch schemes.

Objectives

The primary aim of this review is to assess the effectiveness of neighborhood watch in reducing crime.

Criteria for inclusion of studies

Neighborhood watch sometimes comprises a stand‐alone scheme and sometimes includes additional program elements. The most common combination of program elements is the ‘big three’ (neighborhood watch, property marking and security surveys). Studies were selected for inclusion in the review if they were based on a watch scheme either alone or in combination with any of the other ‘big three’ elements. The main quality control was that the studies should be based on random allocation or a pre‐post test design with a comparison area.

Search Strategy

Studies were identified by searching 11 electronic databases. In addition, studies were sought using on‐line library catalogues, literature reviews, lists of references, and published bibliographies. Leading researchers in the field were also contacted when there was a particular need to do so.

Data collection and analysis

The narrative review was based on 19 studies (covering 43 evaluations) and the meta‐analysis was based on 12 studies (covering 18 evaluations). The data used included police‐recorded crimes and self‐reported victimizations.

Main results

The main finding of the narrative review was that the majority of the schemes evaluated indicated that neighborhood watch was effective in reducing crime.

The main finding of the meta‐analysis was that the weighted mean odds ratio for all studies combined was 1.19 using the fixed effects method and 1.36 using the random effects method. The results of both methods show that neighborhood watch was associated with a reduction in crime of between 16 per cent and 26 per cent.

Reviewers’ conclusions

This review concludes that neighborhood watch is associated with a reduction in crime.

This review should be cited as:

Bennett Trevor, Holloway Katy, and Farrington David. “The Effectiveness of Neighborhood Watch”. In: The Campbell Collaboration Reviews of Intervention and Policy Evaluations (C2‐RIPE).
Effects and impact of witchcraft on Sotho Reformed Churches and the Biblical view of witchcraft
Authors: Semenya David K. , Letsosa Rantoa
Published: June 2013

The aim of this article is to analyse the effects and impact of witchcraft on members of the Basotho Reformed Church who ascribe to witchcraft. From the literature, it is clear that some members of the Basotho Reformed Church practise various forms of witchcraft. Some Christians do not directly involve themselves with practices linked to witchcraft but do participate in healing practices. This article highlights a number of such instances and provides a number of guidelines to churchgoers who are adhering to practices of witchcraft. These guidelines should be relevant to them when they are reflecting on their relationship with the Lord with the aim to live in obedience to God�s Word.
Intermittent left bundle branch block caused by coronary vasospasm
Authors: Alhaji Mohammad
Published: June 2013

Intermittent left bundle branch block (LBBB) has been reported in the literature following certain conditions such as cardiac blunt trauma, myocardial infarction (MI) or exercise induced LBBB. In the majority of cases, the patients usually have underlying coronary arteries disease. LBBB often prevents the electrocardiographic diagnosis of acute MI; therefore, new LBBB in the setting of chest pain is usually treated as transmural MI. We describe a case of patient who presented with intermittent LBBB associated with chest pain, and subsequently the patient was taken to the catheterization laboratory for emergency coronary angiogram, which revealed 80% spasm in left anterior descending artery, which was totally relieved by nitroglycerin infusion. No other significant CAD was noted.
Challenges of Systematic Reviewing Integrative Health Care
Authors: Coulter Ian D. , Khorsan Raheleh , Crawford Cindy , Hsiao An-Fu
Published: June 2013

This article is based on an extensive review of integrative medicine (IM) and integrative health care (IHC). Since there is no general agreement of what constitutes IM/IHC, several major problems were identified that make the review of work in this field problematic. In applying the systematic review methodology, we found that many of those captured articles that used the term integrative medicine were in actuality referring to adjunctive, complementary, or supplemental medicine. The objective of this study was to apply a sensitivity analysis to demonstrate how the results of a systematic review of IM and IHC will differ according to what inclusion criteria is used based on the definition of IM/IHC. By analyzing 4 different scenarios, the authors show that, due to unclear usage of these terms, results vary dramatically, exposing an inconsistent literature base for this field.
Diet, Obesity, and Cancer Progression: Are Adipocytes the Link?
Authors: Toren Paul , Mora Benjamin C. , Venkateswaran Vasundara
Published: June 2013

Obesity has been linked to more aggressive characteristics of several cancers, including breast and prostate cancer. Adipose tissue appears to contribute to paracrine interactions in the tumor microenvironment. In particular, cancer-associated adipocytes interact reciprocally with cancer cells and influence cancer progression. Adipokines secreted from adipocytes likely form a key component of the paracrine signaling in the tumor microenvironment. In vitro coculture models allow for the assessment of specific adipokines in this interaction. Furthermore, micronutrients and macronutrients present in the diet may alter the secretion of adipokines from adipocytes. The effect of dietary fat and specific fatty acids on cancer progression in several in vivo model systems and cancer types is reviewed. The more common approaches of caloric restriction or diet-induced obesity in animal models establish that such dietary changes modulate tumor biology. This review seeks to explore available evidence regarding how diet may modulate tumor characteristics through changes in the role of adipocytes in the tumor microenvironment.
Predicting models for mass and volume of the sweet cherry (Prunus aviumL.) fruits based on some physical traits
Authors: Khadivi-Khub Abdollah , Naderiboldaji Mojtaba
Published: June 2013

Khadivi-Khub, A. and Naderiboldaji, M. 2013. Predicting models for mass and volume of the sweet cherry ( Prunus avium L . ) fruits based on some physical traits. Can. J. Plant Sci. 93: 831–838. There are instances when it is desirable to determine relationships among fruit physical attributes. For example, fruits are often graded on the basis of size and projected area, but it may be more economical to develop a machine which grades by mass or volume. Therefore, the relationships between mass/volume (either mass or volume) and other physical attributes of fruit are needed. In this study three Iranian cultivars (Mashhad, Siah Mashhad, Siah Daneshkadeh), of sweet cherry were selected and the various models for predicting mass/volume of sweet cherry from its dimensions, projected areas, and volume/mass were established. The models were divided into three classifications: (1) single and multiple variable regressions of sweet cherry dimensions, (2) single and multiple variable regressions of projected areas and (3) estimating sweet cherry mass/volume based on its volume/mass. Moreover, some physical characteristics, such as dimensional characteristics, true density, bulk density, and porosity were determined with common methods. Results revealed that mass modeling based on minor diameter, three projected areas, and the measured volume are the best models. The highest determination coefficient in all the models was obtained for mass modeling based on measured volume as R2= 0.93. At last, mass modeling from an economic standpoint was recommended as the most reliable modeling.
Simultaneous measurements of dark carbon fixation and bacterial production in lake sediment
Authors: Santoro Ana Lucia , Bastviken David , Tranvik Lars , Enrich‐Prast Alex
Published: June 2013

Carbon fixation by chemoautotrophic bacteria represents an autochthonous source of organic matter, and may be of particular importance close to redox boundaries. Despite the known sediment chemoautotrophic potential, the quantitative role and the importance of dark carbon fixation (DCF) in lake sediments are still unknown. We provide here a method to measure DCF and bacterial production simultaneously in stratified sediment cores, using 14C labeled dissolved inorganic carbon (DI14C) and 3H‐leucine incorporation. Beyond the total activity, the method allows measurements of the processes over depth, as a profile into the sediment. DCF increased with depth in our profiles, indicating a predominance of anoxic processes. In addition, the method can yield information about the extent DI14C was allocated into the bacterial proteins (DCFp). Slurry and stratified core incubations were compared and yielded similar results for total DCF activity.
Estimating modern carbon burial rates in lakes using a single sediment sample
Authors: Hobbs William O. , Engstrom Daniel R. , Scottler Shawn P. , Zimmer Kyle D. , Cotner James B.
Published: June 2013

The rate of organic carbon (OC) burial in inland waters is an important flux in the global C‐cycle. Here we provide methodological improvements that offer a rapid and accurate assessment of modern OC burial rates in lakes from a single surface‐sediment sample. Using a 93 lake dataset of reliably dated sediment cores (OC burial of 9 to 318 g m−2 y−1), we demonstrate the applicability of this approach in a variety of lake types. We validate our estimated rates of OC burial against (1) measured whole‐lake accumulation from the sum of multiple area‐weighted sediment cores, (2) single central‐basin cores adjusted for sediment focusing, and (3) duplicate sediment cores taken in multiple locations and at different times (4‐10 years apart) in 9 lakes. Our single‐sample estimates, which were in good agreement with measured values, suggest a within‐lake variability of 4 g m−2 y−1 and have a small inter‐lake error of only 6.5%. The applicability of this approach to other lakes and regions requires knowledge of (1) atmospheric 210Pb flux, (2) an estimate of supported 210Pb activity, and (3) some understanding of typical sedimentation rates in the study lakes. This approach provides an accurate assessment of OC burial, with increased potential for greater spatial coverage in inland waters and improved ability to address questions focused on terrestrial—aquatic exchanges of organic carbon.
Selective liquid chromatographic determination of trace domoic acid in seawater and phytoplankton: improvement using the o‐phthaldialdehyde/9‐fluorenylmethylchloroformate derivatization
Authors: Devez Aurélie , Delmas Daniel
Published: June 2013

Domoic acid (DA), a toxin produced worldwide by some species of the genus Pseudo‐nitzschia, is responsible for contamination of marine molluscs, mammals, birds, and for human intoxication, and when detected in high levels results in closures of shellfish farms, thus causing severe economic losses to aquaculture. Studies on algal production of DA in cultures and field samples require sensitive methods capable of measuring trace concentrations of domoic acid. Measuring domoic acid concentrations at trace levels is still a significant challenge. A sensitive and reliable double derivatization using o‐phthaldialdehyde‐mercaptoethanol/9‐fluorenylmethylchloroformate (OPA‐MeSH/FMOC‐Cl) followed by high‐performance liquid chromatography with fluorescence detection has been adapted for the determination of trace levels of dissolved (dDA) and particulate domoic acid (pDA). The selectivity toward domoic acid is greatly improved by eliminating the reaction between FMOC‐Cl and primary amines. Compared with the original Pocklington method, the sensitivity obtained by the double derivatization is largely enhanced (×6) and the reproducibility is significantly increased (<4% relative standard deviation [RSD] for nanomolar domoic acid concentrations). A better precision and an improved interoperator reproducibility were obtained with this two‐step derivatization optimized protocol. This methodology will be useful for monitoring domoic acid production both in Pseudo‐nitzschia cultures and in natural environmental marine samples.
The variability of methane, nitrous oxide and sulfur hexafluoride in Northeast India
Authors: Ganesan A. L. , Chatterjee A. , Prinn R. G. , Harth C. M. , Salameh P. K. , Manning A. J. , Hall B. D. , Mühle J. , Meredith L. K. , Weiss R. F. , O'Doherty S. , Young D.
Published: June 2013

Abstract. High-frequency atmospheric measurements of methane (CH4), nitrous oxide (N2O) and sulfur hexafluoride (SF6) from Darjeeling, India are presented from December 2011 (CH4)/March 2012 (N2O and SF6) through February 2013. These measurements were made on a gas chromatograph equipped with a flame ionization detector and electron capture detector and were calibrated on the Tohoku University, the Scripps Institution of Oceanography (SIO)-98 and SIO-2005 scales for CH4, N2O and SF6, respectively. The observations show large variability and frequent pollution events in CH4 and N2O mole fractions, suggesting significant sources in the regions sampled by Darjeeling throughout the year. In contrast, SF6 mole fractions show little variability and only occasional pollution episodes, likely due to weak sources in the region. Simulations using the Numerical Atmospheric dispersion Modelling Environment (NAME) particle dispersion model suggest that many of the enhancements in the three gases result from the transport of pollutants from the densely populated Indo-Gangetic plains of India to Darjeeling. The meteorology of the region varies considerably throughout the year from Himalayan flows in the winter to the strong South Asian summer monsoon. The model is consistent in simulating a diurnal cycle in CH4 and N2O mole fractions that is present during the winter but absent in the summer and suggests that the signals measured at Darjeeling are dominated by large scale (~100 km) flows rather than local (<10 km) flows.
Nonmigrating tidal signatures in the magnitude and the inter-hemispheric asymmetry of the equatorial ionization anomaly
Authors: Xiong C. , Lühr H.
Published: June 2013

Abstract. Based on nine years of observations from the satellites CHAMP and GRACE the tidal signatures in the magnitude and the inter-hemisphere asymmetry of the equatorial ionization anomaly (EIA) have been investigated in this study. The EIA magnitude parameters show longitudinal wavenumber 4 and 3 (WN4/WN3) patterns during the months around August and December, respectively, while for different EIA parameters the contributions of the various tidal parameters are different. For the crest-to-trough ratio (CTR) the dominating nonmigrating tidal component contributing to WN4 is DE3 during the months around August, while during the months around December solstice the stationary planetary wave, SPW3, takes a comparable role to DE2 in contributing to WN3. For the apex height index (ApexHC) of the EIA fluxtube the stationary planetary waves, SPW4/SPW3, exceed the amplitudes of DE3/DE2 taking the leading role in causing the longitudinal WN4/WN3 patterns. During the months around December solstice the SW3 tide is prominent in both CTR and ApexHC. SW3 shows a strong dependence on the solar flux level, while it is hardly dependent on magnetic activity. For the EIA inter-hemispheric asymmetry only WN1 and WN2 longitudinal patterns can be seen. During June solstice months the pattern can be explained by stationary planetary waves SPW1 and SPW2. Conversely, around December solstice months longitudinal features exhibit some local time evolution, in particular the diurnal nonmigrating tide D0 takes the leading role.
Cross-tail current evolution during substorm dipolarization
Authors: Lui A. T. Y.
Published: June 2013

Abstract. We examine evolution of the cross-tail current during substorm current disruption/dipolarization using observations from two satellites in the near-Earth magnetotail at the downtail distances of 8–9 RE. By choosing times when these two satellites are separated, mainly in the north–south distance in the tail current sheet, precise determination of current density in the layer embedded between these satellites can be obtained with Ampère's law. Two such events are examined and several common features are found. The current densities in the layer embedded by the two satellites were reduced by ~ 40–70% during substorm dipolarization. The changes in current densities have the fast kinetic timescale, i.e., in seconds, implying a kinetic process for current disruption/dipolarization. The estimated power within the current layer was mainly dissipative in the dawn–dusk direction and mainly dynamo in the Sun–tail direction that is needed to drive the north–south substorm current system in the ionosphere. Remote sensing of the energization site with the ion sounding technique shows that the energization site was initially earthward of the satellite and moved down the tail at later times. Breakdown of the frozen-in condition occurred intermittently during the disturbance interval. These features provide important clues to the substorm onset process.
A novel method for diagnosing seasonal to inter-annual surface ocean carbon dynamics from bottle data using neural networks
Authors: Sasse T. P. , McNeil B. I. , Abramowitz G.
Published: June 2013

Abstract. The ocean's role in modulating the observed 1–7 Pg C yr−1 inter-annual variability in atmospheric CO2 growth rate is an important, but poorly constrained process due to current spatio-temporal limitations in ocean carbon measurements. Here, we investigate and develop a non-linear empirical approach to predict inorganic CO2 concentrations (total carbon dioxide (CT) and total alkalinity (AT)) in the global ocean mixed layer from hydrographic properties (temperature, salinity, dissolved oxygen and nutrients). The benefit of this approach is that once the empirical relationship is established, it can be applied to hydrographic datasets that have better spatio-temporal coverage, and therefore provide an additional constraint to diagnose ocean carbon dynamics globally. Previous empirical approaches have employed multiple linear regressions (MLR) and relied on ad hoc geographic and temporal partitioning of carbon data to constrain complex global carbon dynamics in the mixed layer. Synthesizing a new global CT/AT carbon bottle dataset consisting of ~33 000 measurements in the open ocean mixed layer, we develop a neural network based approach to better constrain the non-linear carbon system. The approach classifies features in the global biogeochemical dataset based on their similarity and homogeneity in a self-organizing map (SOM; Kohonen, 1988). After the initial SOM analysis, which includes geographic constraints, we apply a local linear optimizer to the neural network, which considerably enhances the predictive skill of the new approach. We call this new approach SOMLO, or self-organizing multiple linear output. Using independent bottle carbon data, we compare a traditional MLR analysis to our SOMLO approach to capture the spatial CT and AT distributions. We find the SOMLO approach improves predictive skill globally by 19% for CT, with a global capacity to predict CT to within 10.9 μmol kg−1 (9.2 μmol kg−1 for AT). The non-linear SOMLO approach is particularly powerful in complex but important regions like the Southern Ocean, North Atlantic and equatorial Pacific, where residual standard errors were reduced between 25 and 40% over traditional linear methods. We further test the SOMLO technique using the Bermuda Atlantic time series (BATS) and Hawaiian ocean time series (HOT) datasets, where hydrographic data was capable of explaining 90% of the seasonal cycle and inter-annual variability at those multi-decadal time-series stations.