bluuebunny/crossref_metadata_2025 huggingface dataset:
An Investigation on Vibration-based Damage Detection in Circular Plates
Authors: Trendafoilova I. , Gorman D.G. , Manoach E.
Published: March 2009

This study aimed at the development of vibration-based health monitoring methodology for thin circular plates. The possibility of using the first several natural frequencies of a circular plate for damage detection purposes was investigated first. The study then suggested a damage detection method, which considered a vibrating plate as a dynamic system and used its time-domain response represented in a new phase (state) space to extract damage sensitive characteristics. The paper introduced the idea of using large amplitude vibrations and nonlinear time series analysis for damage detection purposes. The suggested damage detection approach explored the possibility to use certain characteristics of the distribution of phase space points on the attractor of the system. It studied the histograms of this distribution and attempts to extract damage sensitive features. Three damage features were suggested and they are shown to detect damage at a rather low level using a finite element model of the plate. The method suggested was rather generic and permits development and application to more complex structures and real data.
Formation of nickel aluminide/nickel hybrid coatings on alloy steels by two step process of nickel plating and low temperature pack aluminisation
Authors: Xiang Z. D. , Datta P. K.
Published: March 2009

The present study investigates the conditions required for forming a hybrid coating consisting of an outer nickel aluminide layer and an inner nickel layer on alloy steels. A commercial alloy steel of 9Cr–1Mo was used as a substrate. Electroless and electronickel plating processes were used to form an initial nickel layer on the steel. The AlCl3 activated packs containing pure Al as a depositing source were then used to aluminise the nickel deposit at temperatures ≤650°C. The effect of phosphorus or boron content in the initial nickel layer deposited with the electroless nickel plating solutions using hypophosphite or boron–hydrogen compound as reducing agent was investigated in relation to the spallation tendency of the coating either immediately after the aluminising process or during the thermal annealing post-aluminising process. Under the aluminising conditions used, the outer nickel aluminide layer formed was Ni2Al3. For the electroplated nickel deposit, the growth kinetics of the outer Ni2Al3 layer during the pack aluminising process was found to obey the parabolic rate law with a parabolic rate constant being 12·67 μm at 650°C for 2 wt-%AlCl3 activated pack containing 4 wt-% pure Al as a deposition source.
Study of precipitation in 2101 duplex stainless steel
Authors: Zhang W. , Jiang L. Z. , Gao J. Q. , Song H. M. , Hu J. C.
Published: March 2009

The precipitation in as aged duplex stainless steel 2101 with composition Fe–21Cr–5·7Mn–1·2Ni–0·23N–0·3Mo was investigated. The precipitates were detected by XRD and TEM and confirmed to be mainly Cr2N, together with some Cr23C6 particles. The precipitation was observed at 650–900°C. TEM analysis showed that plate like Cr2N preferentially nucleated in ferrite grains or at ferrite/ferrite and ferrite/austenite interfaces. At 700°C, many Cr2N particles were observed in specimens aged for only 6–15 min, which indicated that precipitation of Cr2N was rapid.
Preparation and optical properties of GaN nanocrystalline powders
Authors: Jia L. , Xie E. Q. , Pan X. J. , Zhang Z. X. , Zhang Y. Z.
Published: March 2009

GaN nanocrystalline powders were synthesised by decomposition of gallium nitrate, followed by nitrogenising with ammonia under different temperature. X-ray diffraction (XRD) and the transmission electron microscopy (TEM) indicated that the crystallinity of the powder is improved and the average size of the GaN nanocrystallites increases from 4·8 to 23·9 nm as the temperature increases from 850 to 1050°C. The Raman spectra displayed four broadened peaks corresponding to A1 (LO), A1 (TO), E1 (TO) and E2 (high) modes of würtzite GaN respectively. Two additional modes at 252 and 421 cm–1 attributed to boundary phonons activated by the finite size effects and octahedral Ga–N6 bonds were observed respectively. A strong blue photoluminescence (∼353 nm) was detected for room temperature measurement, indicating that the GaN nanocrystalline powders have few defects and high quality.
Formalisation of Wilshire–Scharning methodology to creep life prediction with application to 1Cr–1Mo–0·25V rotor steel
Authors: Evans M.
Published: March 2009

Wilshire and Scharning have recently developed a new methodology that delivers accurate long term creep life predictions, and so offers the prospect of cost effective acquisition of long term creep design data. The present paper develops a procedure for formalising and estimating this Wilshire–Scharning model. Not only does this procedure provide the formalisation required for any acceptable international standard towards creep data acquisition, but it also allows for the construction of confidence limits around the Wilshire–Sharning predictions — something which until now has not been achievable. When applied to 1Cr–1Mo–0·25V steel, it was found that if this material was operated at a stress of 20 MPa, but a temperature of 873 K, there is only a 10% chance of failure at or before 157 702 h, and this could be stated with 95% certainty. The formalisation allows calculations to be carried out for any level of risk and for any material.
Targeted deletion of tumor suppressor PTEN augments neutrophil function and enhances host defense in neutropenia-associated pneumonia
Authors: Li Yitang , Jia Yonghui , Pichavant Muriel , Loison Fabien , Sarraj Bara , Kasorn Anongnard , You Jian , Robson Bryanne E. , Umetsu Dale T. , Mizgerd Joseph P. , Ye Keqiang , Luo Hongbo R.
Published: March 2009

Neutropenia and related infections are the most important dose-limiting toxicities in anticancer chemotherapy and radiotherapy. In this study, we explored a new strategy for augmenting host defense in neutropenia-related pneumonia. Phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3) signaling in neutrophils was elevated by depleting PTEN, a phosphatidylinositol 3′-phosphatase that hydrolyzes PtdIns(3,4,5)P3. In myeloid-specific PTEN knockout mice, significantly more neutrophils were recruited to the inflamed lungs during neutropenia-associated pneumonia. Using an adoptive transfer technique, we demonstrated that this enhancement could be caused directly by PTEN depletion in neutrophils. In addition, disruption of PTEN increased the recruitment of macrophages and elevated proinflammatory cytokines/chemokine levels in the inflamed lungs, which could also be responsible for the enhanced neutrophil recruitment. Depleting PTEN also significantly delayed apoptosis and enhanced the bacteria-killing capability of the recruited neutrophils. Finally, we provide direct evidence that enhancement of neutrophil function by elevating PtdIns(3,4,5)P3 signaling can alleviate pneumonia-associated lung damage and decrease pneumonia-elicited mortality. Collectively, these results not only provide insight into the mechanism of action of PTEN and PtdIns(3,4,5)P3 signaling pathway in modulating neutrophil function during lung infection and inflammation, but they also establish PTEN and related pathways as potential therapeutic targets for treating neutropenia-associated pneumonia.
Factors influencing quality of life in Moroccan postmenopausal women with osteoporotic vertebral fracture assessed by ECOS 16 questionnaire
Authors: Abourazzak Fatima E , Allali Fadoua , Rostom Samira , Hmamouchi Ihsane , Ichchou Linda , El Mansouri Laila , Bennani Loubna , Khazzani Hamza , Abouqal Redouane , Hajjaj-Hassouni Najia
Published: March 2009

Objective

The aim of the study was to evaluate factors influencing quality of life (QOL) in Moroccan postmenopausal women with osteoporotic vertebral fracture assessed by the Arabic version of ECOS 16 questionnaire.

Methods

357 postmenopausal women were included in this study. The participants underwent bone mineral density (BMD) measurements by DXA of the lumbar spine and the total hip as well as X-ray examination of the thoraco-lumbar spine to identify subclinical vertebral fractures. Patients were asked to complete a questionnaire on clinical and sociodemographic parameters, and osteoporosis risk factors. The Arabic version of the ECOS16 (Assessment of health related quality of life in osteoporosis questionnaire) was used to assess quality of life.

Results

The mean age was 58 ± 7.8 years, and the mean BMI was 28.3 ± 4.8 kg/m2. One hundred and eight women (30.1%) were osteoporotic and 46.7% had vertebral fractures. Most were categorized as Grade1 (75%). Three independent factors were associated with a poor quality of life: low educational level (p = 0,01), vertebral fracture (p = 0,03), and history of peripheral fracture (p = 0,006). Worse QOL was observed in the group with vertebral fracture in all domains except "pain": Physical functioning (p = 0,002); Fear of illness (p = 0,001); and Psychosocial functioning (p = 0,007). The number of fractures was a determinant of a low QOL, as indicated by an increased score in physical functioning (p = 0,01), fear of illness (p = 0,007), and total score (p = 0,01) after adjusting on age and educational level. Patients with higher Genant score had low QOL in these two domains too (p = 0,002; p = 0,001 respectively), and in the total score (p = 0,01) after adjusting on age and educational level.

Conclusion

Our current data showed that the quality of life assessed by the Arabic version of the ECOS 16 questionnaire is decreased in post menopausal women with prevalent vertebral fractures, with the increasing number and the severity of vertebral fractures.
Coincident frequencies and relative phases among brain activity and hormonal signals
Authors: Solís-Ortíz Silvia , Campos Rafael G , Félix Julián , Obregón Octavio
Published: March 2009

Background

Fourier transform is a basic tool for analyzing biological signals and is computed for a finite sequence of data sample. The electroencephalographic (EEG) signals analyzed with this method provide only information based on the frequency range, for short periods. In some cases, for long periods it can be useful to know whether EEG signals coincide or have a relative phase between them or with other biological signals. Some studies have evidenced that sex hormones and EEG signals show oscillations in their frequencies across a period of 28 days; so it seems of relevance to seek after possible patterns relating EEG signals and endogenous sex hormones, assumed as long time-periodic functions to determine their typical periods, frequencies and relative phases.

Methods

In this work we propose a method that can be used to analyze brain signals and hormonal levels and obtain frequencies and relative phases among them. This method involves the application of a discrete Fourier Transform on previously reported datasets of absolute power of brain signals delta, theta, alpha1, alpha2, beta1 and beta2 and the endogenous estrogen and progesterone levels along 28 days.

Results

Applying the proposed method to exemplary datasets and comparing each brain signal with both sex hormones signals, we found a characteristic profile of coincident periods and typical relative phases. For the corresponding coincident periods the progesterone seems to be essentially in phase with theta, alpha1, alpha2 and beta1, while delta and beta2 go oppositely. For the relevant coincident periods, the estrogen goes in phase with delta and theta and goes oppositely with alpha2.

Conclusion

Findings suggest that the procedure applied here provides a method to analyze typical frequencies, or periods and phases between signals with the same period. It generates specific patterns for brain signals and hormones and relations among them.
Microdeletion syndromes disclose replication timing alterations of genes unrelated to the missing DNA
Authors: Yeshaya Josepha , Amir Itay , Rimon Ayelet , Freedman Jane , Shohat Mordechai , Avivi Lydia
Published: March 2009

Background

The temporal order of allelic replication is interrelated to the epigenomic profile. A significant epigenetic marker is the asynchronous replication of monoallelically-expressed genes versus the synchronous replication of biallelically-expressed genes. The present study sought to determine whether a microdeletion in the genome affects epigenetic profiles of genes unrelated to the missing segment. In order to test this hypothesis, we checked the replication patterns of two genes – SNRPN, a normally monoallelically expressed gene (assigned to 15q11.13), and the RB1, an archetypic biallelically expressed gene (assigned to 13.q14) in the genomes of patients carrying the 22q11.2 deletion (DiGeorge/Velocardiofacial syndrome) and those carrying the 7q11.23 deletion (Williams syndrome).

Results

The allelic replication timing was determined by fluorescence in situ hybridization (FISH) technology performed on peripheral blood cells. As expected, in the cells of normal subjects the frequency of cells showing asynchronous replication for SNRPN was significantly (P < 10-12) higher than the corresponding value for RB1. In contrast, cells of the deletion-carrying patients exhibited a reversal in this replication pattern: there was a significantly lower frequency of cells engaging in asynchronous replication for SNRPN than for RB1 (P < 10-4 and P < 10-3 for DiGeorge/Velocardiofacial and Williams syndromes, respectively). Accordingly, the significantly lower frequency of cells showing asynchronous replication for SNRPN than for RB1 is a new epigenetic marker distinguishing these deletion syndrome genotypes from normal ones.

Conclusion

In cell samples of each deletion-carrying individual, an aberrant, reversed pattern of replication is delineated, namely, where a monoallelic gene replicates more synchronously than a biallelic gene. This inverted pattern, which appears to be non-deletion-specific, clearly distinguishes cells of deletion-carriers from normal ones. As such, it offers a potential epigenetic marker for suspecting a hidden microdeletion that is too small to be detected by conventional karyotyping methods.
Genetic polymorphisms in DNA base excision repair gene XRCC1 and the risk of squamous cell carcinoma of the head and neck
Authors: Kowalski Michal , Przybylowska Karolina , Rusin Pawel , Olszewski Jurek , Morawiec-Sztandera Alina , Bielecka-Kowalska Anna , Pietruszewska Wioletta , Mlynarski Wojciech , Janusz Szemraj , Majsterek Ireneusz
Published: March 2009

Background

The genes of base excision repair (BER) pathway have been extensively studied in the association with various human cancers. We performed a case-control study to test the association between two common single nucleotide polymorphisms (SNPs) of XRCC1 gene with human head and neck squamous cell carcinoma (HNSCC).

Methods

The genotype analysis of Arg194Trp and Arg399Gln gene polymorphisms for 92 HNSCC patients and 124 controls of cancer free subjects, in Polish population were performed using the PCR-based restriction fragment length polymorphism (PCR-RFLP) with endonuclease Msp I.

Results

No altered risk has been found individually for these SNPs, however haplotypes analysis showed high association with head and neck cancer. The highest frequency, according to wild-type of Arg194Arg and Arg399Arg genotypes, was identified for Arg194Trp-Arg399Arg haplotype (OR, 2.96; 95% CI, 1.01–8.80).

Conclusion

Finally, we identified the combined Arg194Trp-Arg399Arg genotype of base excision repair gene XRCC1 that was associated with HNSCC and may have an impact on identification of a high-risk cancer population.
Greater involvement of people living with HIV in health care
Authors: Morolake Odetoyinbo , Stephens David , Welbourn Alice
Published: March 2009

Greater Involvement of People Living with HIV/AIDS represents a mobilising and an organising principle for the involvement of people living with HIV in program and policy responses. People with HIV have been at the forefront of designing and implementing effective HIV treatment, care and prevention activities. However, governments and health systems have yet to act to fully harness the potential and resources of people living with HIV in addressing the epidemic.

The lives and experiences of people living with HIV highlight the need for a shift in the existing paradigm of disease management. The high prevalence of HIV amongst health care providers in many countries, exacerbated by stigma towards those with HIV in the health care professions, is seriously undermining the capacity of health systems and signals the need to change the current nature of health care delivery. Moreover, the negative experiences of many people with HIV in relation to their health care as well as in their daily social interactions, coupled with the ever‐limited current investment in treatment, care and support, demonstrate that the current system is drastically failing the majority of people with HIV. Current health management systems urgently need to be more effectively maximised, to increase the quality of standards of health care systems and services in resource poor countries. An integrated approach to health care based on a human rights framework, grounded in community realities and delivered in partnership and solidarity with people living with HIV, offers the most viable approach to overcoming the crisis of HIV in the health care system.
Microstructural response and fluid flow mechanisms in cartilage loading: New insights using a novel indentation method
Authors: Thambyah A , Zhao L , Broom N
Published: March 2009

A novel indentation method was used to investigate the response of articular cartilage in the non-directly loaded region. The indenter contained a relief channel that allowed a tissue bulge to develop within it under load. Healthy bovine tissue samples were statically loaded at a nominal compressive stress of 3.6 MPa. The tissue's equilibrium deformed state was chemically fixed. Differential interference contrast microscopy was used to obtain high-resolution images of the deformed microstructure in the region of the tissue bulge.

At the submicro-level, the fibrillar resistance to load is highly complex such that regions of relative compression and tension coincide along a single radial direction. This fibrillar level response is manifested as large-scale matrix shear effects within the bulge region. Further, the surface layer, besides being strain-limiting in the tangential direction, has an intrinsic resistance to axial load. Finally, the pattern of load-induced fluid flow is seen to traverse zonal depths and hence suggests an added complexity to the overall permeability in the deformed tissue matrix.
Application of design of experiments for modelling surface roughness in ultrasonic vibration turning
Authors: Amini S , Nategh M J , Soleimanimehr H
Published: March 2009

The ultrasonic vibration-assisted turning (UAT) is regarded as an advanced machining technique exhibiting distinct advantages over the conventional turning (CT). Superior surface finish of workpieces machined by UAT is one of the advantages. A robust model predicting the surface roughness of the workpieces after UAT is highly desirable when planning the appropriate manufacturing processes. In the present study, the influence of parameters including vibration amplitude, depth of cut, feed rate, and cutting speed on the surface roughness of a workpiece being machined by UAT has been investigated. For this purpose, extensive full factorial UAT experiments were carried out. Similar CT experiments were also performed for comparison with the results of UAT. A mathematical model was then proposed for predicting the surface roughness in UAT on the basis of statistical analysis of the experimental data. The surface roughness created in UAT carried out with the optimal amplitude was constantly lower than CT. This improvement in surface quality was far more significant for finishing operations.
Position tracking control of a clamp-cylinder for energy-saving injection moulding machines with electric-hydrostatic drives
Authors: Cho S H , Räcklebe S , Helduser S
Published: March 2009

This paper deals with the issue of position tracking control of a clamp-cylinder for an injection moulding machine with electric-hydrostatic drives. In order to accommodate mismatches between the real plant and the model used for controller design, discrete-time sliding mode control is developed by combining a velocity feedforward loop. From tracking control experiments, it is shown that significant reduction in position tracking error is achieved through the use of a sliding mode control scheme. The effect of dry-cycle time on position tracking error is examined for the possibility of attaining a high-speed injection moulding machine.
Friction and outwearing of ceramic coatings formed by the microarc oxidation method
Authors: Malyshev V N
Published: March 2009

The microarc oxidation (MAO) method by its power action on treated material can be referred to methods of surface strengthening by concentrated streams of energy. The local action of microarc discharges on a metal surface depends both on electric characteristics of microarc discharge and parameters of electrolyte and on characteristics of treated metal. Good wear resistance of MAO coatings is being explained by a high level of physical and mechanical characteristics and by their structural constitution. The aim of the investigations presented in this article is the estimation of MAO coating wear resistance compared with other wear-resistant materials. The basic trials of materials were conducted on abrasive outwearing using pin-on-disc friction schema. MAO layers with threadlike mono-crystals of α-Al2O3 (emery) have the best mechanical and tribotechnical characteristics. Such microstructures have MAO coatings on aluminium alloys of the Al-Cu-Mg system - duralumin. They represent the most effective structure ensuring high wear resistance.
Tribochemistry, tribocatalysis, and the negative-ion-radical action mechanism
Authors: Kajdas C , Hiratsuka K
Published: March 2009

Terms such as tribochemistry, catalysis, and tribocatalysis are often used to account for various tribological findings, especially those relating to boundary lubrication. The major goal of this article is to present/discuss tribochemistry and tribocatalysis mostly in terms of the negative-ion-radical action mechanism (NIRAM). This article also briefly overviews most recent books and book chapters and discusses selected physical and chemical phenomena in the boundary friction contact concerning tribochemistry and tribocatalysis.

A catalyst provides a new and easier pathway for reactant molecules to be converted into product molecules. What exactly does the term tribocatalysis mean? Is there any relationship between tribochemistry and tribocatalysis? This article attempts to answer these questions and will demonstrate the importance of the NIRAM approach and the concept of NIRAM-hard and soft acids and bases in tribochemistry, catalysis, and tribocatalysis. It is demonstrated that in both tribochemical reactions and some heterogeneous catalytic reactions, intermediate reactive species are formed by the same mechanism mostly governed by the NIRAM approach. Emphasis is on the role of thermal electrons (thermionic emission) on catalysis and both thermal electrons and exo-electrons on tribocatalysis. Some examples of tribocatalytic reactions are also introduced. The relationship between adhesive wear, especially severe-mild wear transition, is discussed from the point of view of tribochemical reactions between environmental gases and a worn surface.
Lubrication of an electroplated nickel matrix silicon carbide coated eutectic aluminium—silicon alloy automotive cylinder bore with an ionic liquid as a lubricant additive
Authors: Mistry K , Fox M F , Priest M
Published: March 2009

For a chromium-nitrided steel piston ring section sliding against an electroplated nickel matrix silicon carbide coated eutectic aluminium—silicon alloy automotive cylinder bore in a reciprocating tribometer, the ionic liquid (IL) imidazolium tetrafluoroborate has an excellent tribological performance as a lubricant additive in the presence of tritolyl phosphate (TTP). A low friction coefficient of 0.015 and a substantial tribofilm was generated. The performance of this base oil/additive combination was superior to the base oil alone or the separate additives in the base oil. The substantial improvement in tribological performance given by addition of an IL and TTP, 1 per cent by volume of each, to a group III base oil indicates a synergistic interaction between the IL and TTP. The need to understand the chemical and physical nature of the tribofilm is emphasized.
Effect of surface dents on contact pressure in elastohydrodynamic contacts
Authors: Křupka I , Vrbka M , Vaverka M , Poliščuk R , Hartl M
Published: March 2009

Nowadays film thickness measurement techniques can provide precise data for the detailed studies of the behaviour of lubricated contacts including transient operational conditions. Contact pressure is in relation with deformation of rubbing surfaces, which can be derived from experimentally evaluated film thickness. Even though the pressure distribution evaluated from measured film thickness is very sensitive to its accuracy, this approach represents a powerful tool for elastohydrodynamic pressure determination; thanks to the relative wide availability of film thickness measurement techniques. Chromatic interferograms can be captured within a few microseconds so that this approach seems to be promising in obtaining relevant pressure data even within non-smooth lubricated contacts. This article presents the results of the effort to extend the applicability of the pressure-film thickness evaluation approach to the non-smooth surfaces. It was found that the main problem is to obtain the film thickness distribution within the whole contact including the inside portion of the deep surface features (e.g. dents). That is why the combination of film thickness data and undeformed dent topography was suggested to overcome these limitations. This approach was validated through the comparison with numerical solution using dented surface and was tested on selected dented contacts operated under thin film and very thin film lubrication conditions.
An alternative simple multibody system approach for modelling rail flexibility in railroad vehicle dynamics
Authors: Shabana A A , Sanborn G
Published: March 2009

In a previous investigation, a non-linear finite element formulation for modelling rail structural flexibility in multibody railroad vehicle systems was presented. This formulation required the use of isoparametric interpolation based on the finite element absolute nodal coordinate formulation (ANCF) in order to have a consistent interpolation for the geometry in the current deformed configuration. That is, the same interpolation functions used for the geometry description in the undeformed reference state are also used for predicting the geometry in the current deformed state. This approach, however, becomes less attractive when a degree of derivative continuity higher than the one provided by ANCF elements is required. In this investigation, an alternate simpler approach is proposed for modelling rail and track flexibility. The proposed new method, which is based on the floating frame of reference formulation, allows for general modelling of rail and track flexibility, can be used to impose a higher degree of continuity on the derivatives at the nodes that define the rail geometry in the reference configuration, and can be used to systematically couple finite element computer programs with flexible multibody system codes, allowing for the development of detailed track models that include rail, tie, and fastener flexibility as well as soil characteristics. In the proposed method, track geometry is defined in a preprocessor computer program using nodal points. In addition to the location of the nodes and Euler angles that define the orientation of the profile frame at the nodes, first, second, and third derivatives of the locations and Euler angles are defined by the preprocessor computer program. Numerical examples are presented in order to demonstrate the effect of track deformation in railroad applications.
Characterisation of Anthracyclines from a Cosmomycin D-Producing Species of Streptomyces by Collisionally-Activated Dissociation and Ion Mobility Mass Spectrometry
Authors: Kelso Celine , Rojas Juan Diego , Furlan Renata L.A. , Padilla Gabriel , Beck Jennifer L.
Published: March 2009

Cultures of cosmomycin D-producing Streptomyces olindensis ICB20 that were propagated for many generations underwent mutations that resulted in production of a range of related anthracyclines by the bacteria. The anthracyclines that retained the two trisaccharide chains of the parent compound were separated by HPLC. Exact mass determination of these compounds revealed that they differed from cosmomycin D (CosD) in that they contained one to three fewer oxygen atoms (loss of hydroxyl groups). Some of the anthracyclines that were separated by HPLC had the same mass. The location from which the hydroxyl groups had been lost relative to CosD (on the aglycone and/or on the sugar residues) was probed by collisionally-activated dissociation using an electrospray ionisation linear quadrupole ion trap mass spectrometer. The presence of anthracyclines with the same mass, but different structure, was confirmed using an electrospray ionisation travelling wave ion mobility mass spectrometer.
Development of an Ion Trap/Multi-Turn Time-of-Flight Mass Spectrometer with Potential-Lift
Authors: Iwamoto Kenichi , Nagao Hirofumi , Toyoda Michisato
Published: March 2009

An ion trap/multi-turn time-of-flight (ToF) mass spectrometer with potential-lift has been developed. This system consists of an external ion source, a lens system, an ion trap, a potential-lift, a multi-turn ToF mass spectrometer and a detector. The ion trap consists of hyperbolic electrode cross-sections (Paul trap) and is used as an ion storage device. The potential-lift, which is part of the flight tube, was attached between the ion trap and the multi-turn ToF mass spectrometer. The potential-lift is known to be useful for increasing the kinetic energy of the ions. In order to check the ability of the potential-lift, mass distributions of [(CsI) n Cs]+ clusters ( n = 1–9) were measured. The relative intensity ratios of the [(CsI) nCs]+ clusters were consistent with the results obtained using other apparatus. To check the properties of the new apparatus, Xe+ isotopes were analyzed using either a linear or multi-turn ToF mass spectrometer. In the linear mode, the mass resolution was 500. In the multi-turn mode, the resolution depended on the number of cycles of the multi-turn ToF mass spectrometer; the mass resolution was 4400 (FWHM) after nine cycles. This new apparatus with a high resolution will be useful for measurements of ion–molecule reactions and photodissociations.
Gas-Phase Ion Chemistry of Protonated Melatonin
Authors: Bongiorno David , Ceraulo Leopoldo , Camarda Lorenzo , Ciofalo Maurizio , Ferrugia Mirella , Indelicato Serena , Mele Andrea , Liveri Vincenzo Turco
Published: March 2009

The gas-phase ion chemistry of protonated melatonin has been investigated by mass spectrometric (MS) techniques involving chemical ionisation, fast atom bombardment and electrospray ionisation. Either naturally-occurring or collision-induced decomposition experiments have been carried out using side chain tetra-deuterium-labelled derivatives, as well as the corresponding N–D derivatives obtained by exchange with D2O. The analysis of experimental results allows definite pathways for the formation of the ion at m/z 174 to be assigned and sheds some more light on the overall fragmentation pathways. Experiments on labelled derivatives evidenced H–D scrambling processes during fragmentation.
Application of Effective Potential Approach to Ion Dynamics Investigation in Field Asymmetric Ion Mobility Spectrometry Conditions
Authors: Nikolaev Eugene N. , Vedenov Alexander A.
Published: March 2009

The theory of ion motion in field asymmetric ion mobility spectrometry (FAIMS) conditions has been developed on the bases of an effective field approach and applied to cylindrical and spherical geometries of FAIMS analyzers. The resulting analytical formulae relate compensation voltage to ion characteristics such as non-linear ion mobility coefficient, ion mobility and ion mass and charge. They permit taking into account ion inertia at small pressure of a buffer gas and at high ion mass.
Undergraduate anatomy teaching in the UK
Authors: Gogalniceanu P , O'Connor E Fitzgerald , Raftery A
Published: March 2009

The UK undergraduate medical curriculum has undergone significant changes following the recommendation of Tomorrow's Doctors, a report by the UK's General Medical Council (GMC). One consequence of these reforms is believed to be an overall reduction in basic science teaching. Many anatomists, surgeons and medical students have objected to the reduction in anatomy teaching time, the diminishing role of dissection and the inadequate assessment of students' knowledge of anatomy. Moreover, there have been concerns regarding the future of anatomy as an academic subject as well as the fitness to practise of junior doctors. Currently there is much debate as to whether the UK is experiencing a real or apparent crisis in anatomy teaching.
Seize the day and take heed of tomorrow
Authors: Black John
Published: March 2009

My newsletter in the February Bulletin about College strategy to alleviate the effects of the European Working Time Directive (EWTD) has certainly 'seized the day'. Support for an opt-out for surgery has been expressed across the board and I cannot recall an issue on which surgeons of all grades, across every specialty and from all parts of the country, have been so united. I thank all of you who have emailed your support, written to me and spoken out at meetings locally and nationally.
Celecoxib-Associated Anaphylaxis
Authors: Chamberlin Kevin W , Silverman Adam R
Published: March 2009

Objective:

To report and discuss a case of anaphylaxis in a young, healthy white male taking celecoxib for intermittent lower back pain.

Case Summary:

A healthy 27-year-old man with a documented history of anaphylaxis to penicillins and macrolides presented to the emergency department (ED) in anaphylactic shock after ingesting a 200-mg capsule of celecoxib and a cup of orange juice. The patient had been taking celecoxib over the past 6 months, for 1-2 weeks at a time, for low back pain secondary to a pilonidal cyst and an L5/S1 bulging disc. The day of admission was the seventh day of the most recent course of twice-daily celecoxib. The patient initially self-treated the reaction with diphenhydramine and subcutaneous epinephrine that he had at home due to his history of drug- and bee sting-induced anaphylaxis; neither intervention improved his symptoms, He became profoundly diaphoretic and developed systemic swelling, shortness of breath, bradycardia, and hypotension. Emergency medical services transported the patient to the ED, where he was treated appropriately and the symptoms resolved. However, 4 hours later, at time of discharge from the ED, the symptoms recurred. He was admitted to the intensive care unit and monitored for 3 days. Supportive care, steroids, and histamine blockade provided resolution of the symptoms. Cardiac workup was initiated because of the recunence and severity of bradycardia and hypotension; results of the workup were unremarkable. The patient was discharged in stable condition.

Discussion:

This case demonstrates rare anaphylaxis to celecoxib in a patient who had previously taken the drug and who had documented tolerance to sulfonamide antibiotics. Despite this history, our patient developed type V immunoglobulin E-mediated anaphylaxis secondary to the sulfonamide component of celecoxib. This reaction was considered probable according to the Naranjo probability scale. A review of published case reports and related atlergy literature for celecoxib allergenicity revealed that such reactions are rare. This is the first case report with great detail of a patient with anaphylaxis to celecoxib after having previously tolerated the medication.

Conclusions:

Celecoxib can produce an anaphylactic reaction in patients who have previously tolerated sulfonamide antibiotics and who have previously tolerated celecoxib. This case also reviews the potentially biphasic presentation of anaphylaxis. Clinicians need to be aware of this biphasic anaphylactic response to ensure optimal duration of evaluation.
Influence of Irradiation on the Creep/Fatigue Behavior of Several Austenitic Stainless Steels and Incoloy 800 at 700 C
Authors: Brinkman CR , Korth GE , Beeston JM
Published: March 2009

Results from elevated temperature-strain controlled fatigue and constant-strain-rate tensile tests conducted on specimens of stainless steel Types 304, 304L (titanium modified), 316, as well as Incoloy 800 are reported. Specimens were irradiated to fluences of 0.4 to 5 × 1022 n/cm2, E>0.1 MeV at 700 to 750 C (1292 to 1382 F), while the postirradiation test temperature was maintained at 700 C. Reductions in tensile ductility and fatigue life occurred, with reductions in fatigue life ranging from factors of approximately 1.5 to 2.5 for the stainless steels and up to 35 for Incoloy 800 in comparison with the thermal controls. Comparisons are made between actual irradiated fatigue behavior and predictions based on several semi-empirical methods using irradiated tensile data. These methods generally provided good estimates of the irradiated fatigue behavior of these materials. Introducing tensile hold times into the fatigue cycles of irradiated and unirradiated Type 316 stainless steel resulted in substantial reductions in the fatigue life of this material. However, for tensile hold times in excess of 0.1 h a tendency towards saturation of the hold-time effect was found in both the irradiated and unirradiated material. Creep and fatigue damage for Type 316 stainless was determined and summed linearly. This total damage was found to be a function of strain range, duration of tensile hold time, and irradiation condition for Type 316 stainless steel.
Chapter 26—Radiation Effects and Shielding
Authors: Polivka M , Davis HS
Published: March 2009

Portland cement concrete is an ideal material for use in construction of radiation shields. Although there are other materials that could be employed for radiation shielding purposes, concrete is not only economical, but it also has the advantage of being a material that can be cast into any desired homogeneous structural shape. Concrete is now commonly used for shielding of atomic research facilities, nuclear power plants, and for radiation medical and research units or equipment.
Low-Cycle Fatigue Behavior of Types 304 and 316 Stainless Steel at LMFBR Operating Temperature
Authors: Cheng CF , Cheng CY , Diercks DR , Weeks RW
Published: March 2009

Fully reversed, axial strain-controlled low-cycle fatigue tests with and without tension holdtime have been conducted in air in the temperature range of 806 to 1202 F and at a strain rate of 4 × 10-3 1 on Types 304 and 316 stainless steel after various initial heat treatments. The test results have been supplemented by metallographic and scanning electron microscopy investigations. Prior heat treatment has a greater effect on specimens tested at 1050 F than on those tested at 1202 F and a greater effect on Type 304 than on Type 316. The introduction of tension holdtimes decreases the cyclic life of both materials and causes the mode of failure to change from transgranular to intergranular. Much of the above fatigue behavior can be qualitatively understood on the basis of the supplemental metallographic results.
Elevated Temperature Properties as Influenced by Nitrogen Additions to Types 304 and 316 Austenitic Stainless Steels
Authors: Rozic EJ
Published: March 2009

Description

The Symposium on Elevated Temperature Properties as Influenced by Nitrogen Additions to Types 304 and 316 Austenitic Stainless Steels was presented at an informal workshop session held at the 72nd Annual Meeting of the Society, in Atlantic City, N. J., 22—27 June 1969. The sponsors of this symposium included the Joint Committee on Effect of Temperature on the Properties of Metals, Metals Properties Council, American Society for Testing and Materials, and American Society of Mechanical Engineers. J. J. Heger, U. S. Steel Corporation, and G. V. Smith, consultant, served as co-chairmen.
Applications of Composite Materials
Authors: Salkind MJ , Holister GS
Published: March 2009

Description

The technology of high performance fiber composites has been with us for only one decade. Although fiberglass has been available for many years, the discovery of boron fiber in the early 1960's, followed quickly by graphite and other fibers, ushered in a new era of structural composites which included the rediscovery of fiberglass for critical, highly loaded structures.
Effects of Radiation on Substructure and Mechanical Properties of Metals and Alloys
Authors: Moteff J
Published: March 2009

Description

The Symposium on Effects of Radiation on Substructure and Mechanical Properties of Metals and Alloys was presented at Los Angeles, Calif., 26-28 June 1972 in conjunction with the Seventy-fifth Annual Meeting of the American Society for Testing and Materials. The symposium was sponsored by ASTM Committee E10 on Radioisotopes and Radiation Effects. John Moteff, Materials Science and Metallurgical Engineering Department, University of Cincinnati, served as chairman of the symposium committee, which consisted of C. J. Baroch, A. L. Bement, E. Landerman, F. R. Shober, and K. M. Zwilsky. The six sessions were presided over by: L. R. Steele, H. Bohm, J. R. Weir, T.T. Claudson, I. P. Bell and K.M. Zwilsky, and S.D. Harkness and C. Y. Li.
Disposal of Plastics with Minimum Environmental Impact
Authors: Mackinney HW
Published: March 2009

Description

Five papers covering recycling, degradability, incineration and reuse of plastics. A basic book for those concerned with environmental problems.
Manual of Industrial Corrosion Standards and Control
Authors: Cocks FH
Published: March 2009

Description

A comprehensive 11 Chapter volume covering corrosion in petroleum, gas, automotive, pipeline, telephone, marine, nuclear, chemical, nonferrous and ferrous industries.
Sensory Evaluation of Appearance of Materials
Authors: Hunter RS , Martin PN
Published: March 2009

Description

Because of the overlapping interest of ASTM Committees E12 on Appearance of Materials and E18 on Sensory Evaluation of Materials and Products in vision and appearance, they have maintained liaison for many years, and joint sponsorship of this symposium was very appropriate. For Committee E12 the symposium effort represented an extension beyond instrumental measurements, which had received most of their attention. For Committee E18 it was a follow-up to ASTM Special Technical Publication 433, "Basic Principles of Sensory Evaluation" (1968), which included a chapter on vision and general chapters applying to all the senses. W. H. Danker, who was Chairman of Subcommittee E18.02 during the early planning in 1970 and 1971, was largely responsible for the initial proposal for a joint effort of the two committees and the later proposal that this effort take the form of a symposium. W. J. Kiernan, who was Chairman of Committee E12 in 1970, gave enthusiastic support to the proposed project and contributed many valuable suggestions for getting it underway.
Technical Advances in Packaging with Flexible Barrier Materials
Authors: Gilbert SG
Published: March 2009

Description

Five papers discuss some problems associated with flexible packaging materials. Of particular interest to the food industry.
An Integrative Suicide Prevention Program for Visitor Charcoal Burning Suicide and Suicide Pact
Authors: Paul W. C. Wong DPsyc (Clinical)  , Liu Patricia M. Y. , Chan Wincy S. C. , Law Y. W. , Law Steven C. K. , Fu King‐Wa , Li Hana S. H. , Tso M. K. , Beautrais Annette L. , Yip Paul S. F.
Published: March 2009

An integrative suicide prevention program was implemented to tackle an outbreak of visitor charcoal burning suicides in Cheung Chau, an island in Hong Kong, in 2002. This study evaluated the effectiveness of the program. The numbers of visitor suicides reduced from 37 deaths in the 51 months prior to program implementation to 6 deaths in the 42 months post‐implementation period. The number of visitor suicide pacts decreased from 7 pacts (15 individuals) to 1 pact (2 individuals). No statistically significant differences in the numbers of visitor suicide attempts and resident suicides were observed in the two time periods. No statistically significant changes in visitor suicides during the study period were observed on the comparison islands. The consistency and timing of reduction in visitor suicides correlated with the development and delivery of the integrative program on the intervention island, suggesting a causal association between program delivery and reduction of visitor suicides. The possibility of displacement seems small because there was no increase in visitor suicides on the comparison islands during the study period. This integrative approach in preventing target‐specific suicides may serve as an example for other communities to develop suicide prevention programs that make use of the existing local resources.
Factors Affecting Accuracy From Genomic Selection in Populations Derived From Multiple Inbred Lines: A Barley Case Study
Authors: Zhong Shengqiang , Dekkers Jack C M , Fernando Rohan L , Jannink Jean-Luc
Published: March 2009

We compared the accuracies of four genomic-selection prediction methods as affected by marker density, level of linkage disequilibrium (LD), quantitative trait locus (QTL) number, sample size, and level of replication in populations generated from multiple inbred lines. Marker data on 42 two-row spring barley inbred lines were used to simulate high and low LD populations from multiple inbred line crosses: the first included many small full-sib families and the second was derived from five generations of random mating. True breeding values (TBV) were simulated on the basis of 20 or 80 additive QTL. Methods used to derive genomic estimated breeding values (GEBV) were random regression best linear unbiased prediction (RR–BLUP), Bayes-B, a Bayesian shrinkage regression method, and BLUP from a mixed model analysis using a relationship matrix calculated from marker data. Using the best methods, accuracies of GEBV were comparable to accuracies from phenotype for predicting TBV without requiring the time and expense of field evaluation. We identified a trade-off between a method's ability to capture marker-QTL LD vs. marker-based relatedness of individuals. The Bayesian shrinkage regression method primarily captured LD, the BLUP methods captured relationships, while Bayes-B captured both. Under most of the study scenarios, mixed-model analysis using a marker-derived relationship matrix (BLUP) was more accurate than methods that directly estimated marker effects, suggesting that relationship information was more valuable than LD information. When markers were in strong LD with large-effect QTL, or when predictions were made on individuals several generations removed from the training data set, however, the ranking of method performance was reversed and BLUP had the lowest accuracy.