bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental tests of the role of predation in the population dynamics of voles and lemmings
Authors: SUNDELL JANNE
Published: November 2006

Reasons for fluctuating populations of small mammals have been intensively investigated since the early days of modern ecology. Particular interest has been taken in vole populations exhibiting multiannual oscillations. Much empirical and theoretical work has been accomplished to find out the key factor(s) driving these population cycles and many reviews have been written about the results.

One of the most plausible processes for explaining regular fluctuations in small mammals is predation. Here I review the existing literature on the experimental studies of the role of predation in vole population dynamics in the hope that a critical examination of these studies will help researchers improve the design of future experiments.

Most predation manipulations have been done in exclosures, but there are also studies that have attempted to reduce or increase predator numbers in non‐fenced areas, islands and enclosures.

As the number of experimental studies has increased, their quality in terms of replication, use of controls and realistic spatial and temporal scales has also improved.

Most studies have found population‐level effects of predator manipulations on prey populations. The effects have varied from very weak to very strong, reflecting dissimilar experimental designs and the great variety of predator–prey interactions among different kinds of species in different landscapes. Most of these studies show that predation limits population growth of voles, and in some circumstances even regulate vole population fluctuations, but none of them clearly demonstrates that predation consistently changes fluctuation patterns of voles.

To be able to assess more reliably the true role of predation on (cyclic) population fluctuations of voles, more competent experiments are still needed not only over the geographical range of cyclic population dynamics, but also in areas of weakly or non‐cyclic populations of voles.
Assessing the taxonomic status of dingoes Canis familiaris dingo for conservation
Authors: ELLEDGE AMANDA E. , LEUNG LUKE K.‐P. , ALLEN LEE R. , FIRESTONE KAREN , WILTON ALAN N.
Published: November 2006

The conservation status of the dingo Canis familiaris dingo is threatened by hybridization with the domestic dog C. familiaris familiaris. A practical method that can estimate the different levels of hybridization in the field is urgently required so that animals below a specific threshold of dingo ancestry (e.g. 1/4 or 1/2 dingoes) can reliably be identified and removed from dingo populations.

Skull morphology has been traditionally used to assess dingo purity, but this method does not discriminate between the different levels of dingo ancestry in hybrids. Furthermore, measurements can only be reliably taken from the skulls of dead animals.

Methods based on the analysis of variation in DNA are able to discriminate between the different levels of hybridization, but the validity of this method has been questioned because the materials currently used as a reference for dingoes are from captive animals of unproven genetic purity. The use of pre‐European materials would improve the accuracy of this method, but suitable material has not been found in sufficient quantity to develop a reliable reference population. Furthermore, current methods based on DNA are impractical for the field‐based discrimination of hybrids because samples require laboratory analysis.

Coat colour has also been used to estimate the extent of hybridization and is possibly the most practical method to apply in the field. However, this method may not be as powerful as genetic or morphological analyses because some hybrids (e.g. Australian cattle dog × dingo) are similar to dingoes in coat colour and body form. This problem may be alleviated by using additional visual characteristics such as the presence/absence of ticking and white markings.
Novel DNA binding protein SarZ contributes to virulence in Staphylococcus aureus
Authors: Kaito Chikara , Morishita Daisuke , Matsumoto Yasuhiko , Kurokawa Kenji , Sekimizu Kazuhisa
Published: November 2006

We previously reported that the cvfA gene is a virulence regulatory gene in Staphylococcus aureus. Here, we identified a novel gene named sarZ that acts as a multicopy suppressor of decreased haemolysin production in the cvfA deletion mutant. The amount of sarZ transcripts was decreased in the cvfA mutant. The sarZ‐deletion mutant produced less haemolysin and attenuated virulence in a silkworm‐infection model and a mouse‐infection model. The amino acid sequence of the sarZ gene product had 19% identity with the transcription factor MarR in Escherichia coli, and the internal region contained a winged helix–turn–helix motif (wHTH), a known DNA binding domain. Purified recombinant SarZ protein had binding affinity for the promoter region of the hla gene that encodes α‐haemolysin. SarZ mutant proteins with an amino acid substitution in the N‐terminal region or in the wHTH motif had significantly decreased DNA binding. The mutated sarZ genes encoding SarZ mutant proteins with a low affinity for DNA did not complement the decreased haemolysin production or the attenuated killing ability against silkworms in the sarZ mutant. These results suggest that the DNA binding activity of the SarZ protein is required for virulence in S. aureus.
Control of fatty acid desaturation: a mechanism conserved from bacteria to humans
Authors: Aguilar Pablo S. , De Mendoza Diego
Published: November 2006

Unsaturated fatty acids (UFAs) have profound effects on the fluidity and function of biological membranes. Microorganisms, plants and animals regulate the synthesis of UFAs during changing environmental conditions as well as in response to nutrients. UFAs homeostasis in many organisms is achieved by feedback regulation of fatty acid desaturase gene transcription through signalling pathways that are governed by sensors embedded in cellular membranes. Here, we review recently discovered components of the regulatory machinery governing the transcription of fatty acid desaturases in bacteria, yeasts and animals that indicate an ancient role of transmembrane signalling mechanisms and integrate membrane composition with lipid biosynthesis.
Apoptosis in yeast – mechanisms and benefits to a unicellular organism
Authors: Gourlay Campbell W. , Du Wei , Ayscough Kathryn R.
Published: November 2006

Initial observations that the budding yeast Saccharomyces cerevisiae can be induced to undergo a form of cell death exhibiting typical markers of apoptosis has led to the emergence of a thriving new field of research. Since this discovery, a number of conserved pro‐ and antiapoptotic proteins have been identified in yeast. Indeed, early experiments have successfully validated yeasts as a powerful genetic tool with which to investigate mechanisms of apoptosis. However, we still have little understanding as to why programmes of cell suicide exist in unicellular organisms and how they may be benefit such organisms. Recent research has begun to elucidate pathways that regulate yeast apoptosis in response to environmental stimuli. These reports strengthen the idea that physiologically relevant mechanisms of programmed cell death are present, and that these function as important regulators of yeast cell populations.
Distinct roles of electric and hydraulic signals on the reaction of leaf gas exchange upon re‐irrigation in Zea mays L.
Authors: GRAMS THORSTEN E. E. , KOZIOLEK CHRISTIANE , LAUTNER SILKE , MATYSSEK RAINER , FROMM JÖRG
Published: November 2006

The hypothesis that electric and hydraulic long‐distance signals modify photosynthesis and stomatal aperture upon re‐irrigation in intact drought‐stressed plants was examined. Maize plants (Zea mays L.) were exposed to drought conditions by decreasing the soil water content to 40–50% of field capacity. The decrease in water content resulted in a decline in stomatal conductance to 50–60% of the level in well‐watered plants. Re‐irrigation of the plants initiated both hydraulic and electric signals, followed by a two‐phase response of the net CO2 uptake rate and stomatal conductance of leaves. The transitional first phase (phase 1) is characterized by a rapid decrease in both levels. In the second phase (phase 2), both parameters gradually increase to levels above those of drought‐stressed plants. Elimination of either the hydraulic signal by compensatory pressure application to the root system, or of the electric signal by cooling of the leaf blade gave evidence that the two signals (1) propagated independently from each other and (2) triggered the two‐phase response in leaf gas exchange. The results provided evidence that the hydraulic signal initiated a hydropassive decrease in stomatal aperture and for the involvement of electric signals in the regulation of photosynthesis of drought‐stressed plants.
An overview on congenital alopecia in domestic animals
Authors: Mecklenburg Lars
Published: November 2006

Alopecia, that is, lack of hair in any quantity, is a frequent complaint of pet owners. Although mostly acquired, rare congenital forms of alopecia exist that are associated with abnormalities in hair follicle morphogenesis. Congenital alopecias can result in changes in quality or quantity of hair follicles and the hair fibres produced by them. They vary in terms of clinical presentation and mode of inheritance. Histopathology is usually needed in order to differentiate between a reduced number of otherwise normal hair follicles and qualitative hair follicle abnormalities. Although our understanding of the molecular mechanisms that drive hair follicle morphogenesis in mice and humans has significantly increased during the last decade, still very little is known about congenital alopecias in domestic animals. Because of their rarity and the general lack of knowledge about their pathophysiology, classification of congenital alopecias in domestic animals is still unsatisfactory.

This article reviews hair follicle morphogenesis and its most important molecular mechanisms, and it discusses the various forms of congenital alopecia occurring in domestic animals that have been described in the literature, differentiating between hair follicle aplasia, hair follicle dysplasia (i.e. defects associated with hair follicle development and defects associated with hair shaft formation), and neuroectodermal dysplasias, the latter involving the hair follicle pigmentary system.
Evaluation of a serological test (indirect ELISA) for the diagnosis of sarcoptic mange in red foxes (Vulpes vulpes)
Authors: Bornstein Set , Frössling Jenny , Näslund Katarina , Zakrisson Göran , Mörner Torsten
Published: November 2006

Sarcoptic mange occurs in many parts of the world and is common in populations of domestic and wild canids, including red foxes (Vulpes vulpes). In recent years, an indirect antibody enzyme‐linked immunosorbent assay (ELISA), with higher sensitivity and specificity than traditional diagnostic methods, has been successfully applied in the diagnosis of sarcoptic mange in dogs. The same ELISA has also demonstrated specific antibodies toSarcoptes scabieiin experimentally infected red foxes. The aim of this study was to evaluate the indirect ELISA when used to detect antibodies toS. scabieiin field sera from Swedish red foxes. One cohort of both infected and non‐infected red foxes (cohort 1;n = 88), and one cohort of apparently non‐infected foxes (cohort 2;n = 67) were examined for skin lesions and presence ofS. scabieiby thorough visual examination at autopsy and skin scrapings. Samples of blood‐tinted body liquid from the abdomen or thorax cavity were collected and analysed by the indirect ELISA. The relative sensitivity and specificity of the ELISA at different cut‐offs (OD values) were estimated by comparing the test results to the infection status as determined by examination and skin scrapings. The highest combination of relative sensitivity and specificity, calculated based on cohort 1, was 95.4 and 100.0%, respectively. These estimates were constant for cut‐offs 0.150–0.225, which included the cut‐off based on the mean plus three standard deviations of test results from cohort 2 (0.165). It is concluded that this test can be useful in diagnosis and epidemiological studies ofS. scabieiinfection in red foxes.
Evaluation of the effects of topical tripeptide‐copper complex and zinc oxide on open‐wound healing in rabbits
Authors: Cangul I. Taci , Gul Nihal Y. , Topal Ayse , Yilmaz Rahsan
Published: November 2006

In this study the clinical and histopathological effects of topically applied tripeptide‐copper complex (TCC) and zinc oxide on open‐wound healing in rabbits was evaluated. Eighteen New Zealand rabbits were divided into three groups: TCC, zinc oxide and no treatment. One full thickness wound was created on each side of the dorsal midline in each rabbit. Wound margins were traced on days 0, 7, 14, and 21 and topical TCC and zinc oxide were applied daily for 21 days to each rabbit in the respective treatment groups. The mean unhealed wound area was significantly smaller in the TCC than in the zinc oxide group on day 7, but it was significantly smaller in the TCC group than in to the control group on days 7, 14 and 21. The mean percentage of wound contraction on day 7 was significantly higher in the TCC than in the zinc oxide group; however, it was significantly higher in the TCC group than in the control group on days 7, 14 and 21. Median time for the coverage of the wound bed with granulation tissue was significantly shorter in the TCC group than in the other groups. Filling of the open wound with granulation tissue to skin level was significantly slower in the control group than in the other two groups. Neutrophil counts decreased regardless of the group in parallel with healing, while neovascularization was best observed in the TCC group. The results suggest that TCC is a better choice in the treatment protocols of open wounds in rabbits than zinc oxide.
Putting informed and shared decision making into practice
Authors: Towle Angela , Godolphin William , Grams Garry , LaMarre Amanda
Published: November 2006

Objective  To investigate the practice, experiences and views of motivated and trained family physicians as they attempt to implement informed and shared decision making (ISDM) in routine practice and to identify and understand the barriers they encounter.

Background  Patient involvement in decision making about their health care has been the focus of much academic activity. Although significant conceptual and experimental work has been done, ISDM rarely occurs. Physician attitudes and lack of training are identified barriers.

Design  Qualitative analysis of transcripts of consultations and key informant group interviews.

Settings and participants  Six family physicians received training in the ISDM competencies. Audiotapes of office consultations were made before and after training. Transcripts of consultations were examined to identify behavioural markers associated with each competency and the range of expression of the competencies. The physicians attended group interviews at the end of the study to explore experiences of ISDM.

Results  The physicians liked the ISDM model and thought that they should put it into practice. Evidence from transcripts indicated they were able to elicit concerns, ideas and expectations (although not about management) and agree an action plan. They did not elicit preferences for role or information. They sometimes offered choices. They had difficulty achieving full expression of any of the competencies and integrating ISDM into their script for the medical interview. The study also identified a variety of competency‐specific barriers.

Conclusion  A major barrier to the practice of ISDM by motivated physicians appears to be the need to change well‐established patterns of communication with patients.
The interactions of phenytoin and its binding site in DI‐S6 segment of Na+channel voltage‐gated peptide by NMR spectroscopy and molecular modeling study
Authors: Lou B.‐S. , Lin T.‐H. , Lo C.‐Z.
Published: November 2006

Abstract: Nuclear magnetic resonance (NMR) spectra of a model peptide (BL‐DIS6), in the presence of anticonvulsant diphenyl drug, phenytoin (DPH), were measured to obtain the interactions between the selected drug and the model peptide. BL‐DIS6's sequence corresponds to the S6 segment in domain I of rat brain type IIA Na+‐channel. NMR studies have demonstrated that the magnitude of the chemical shifts of amide‐ andα‐protons can be used as a measurement of the complex stability and binding site of the peptide. Our NMR results propose a 310‐helical structure for BL‐DIS6, and suggest a binding cavity forDPHthat involves the hydrophobic particles of residues Ans‐7, Leu‐8, Val‐11, and Val‐12. Furthermore, molecular modeling was performed to provide a possible complex conformation that the phenyl portion ofDPHis accommodated in the proximity of the C‐terminal residues Ala‐11 and Val‐12, and simultaneously the heterocyclic amine ring ofDPHis perching at the residue Asn‐7 periphery and stabilizing the phenyl portion deep insertion into the peptide.
Tryptophan replacement in the nociceptin/orphanin FQ receptor ligand Ac‐RYYRWK‐NH2
Authors: Carra' G. , Calo' G. , Spagnolo B. , Guerrini R. , Arduin M. , Marzola E. , Trapella C. , Regoli D. , Salvadori S.
Published: November 2006

Abstract: In the present study we describe the in vitro pharmacological characterization of the nociceptin/orphanin FQ (N/OFQ) receptor (NOP) ligand Ac‐RYYRWK‐NH2and the synthesis and biological evaluation of 13 Trp5substituted Ac‐RYYRWK‐NH2analogs. Results indicate that Ac‐RYYRWK‐NH2behaves as a highly potent and selective partial agonist at the NOP receptors and that the whole indole moiety of the Trp5side chain is not required, being a phenyl‐ethyl side chain already sufficient for maintaining high potency.
Towards genetic markers in animal populations as biomonitors for human‐induced environmental change
Authors: Hoffmann Ary A. , Daborn Phillip J.
Published: November 2006

Genetic markers provide potentially sensitive indicators of changes in environmental conditions because the genetic constitution of populations is normally altered well before populations become extinct. Genetic indicators in populations include overall genetic diversity, genetic changes in traits measured at the phenotypic level, and evolution at specific loci under selection. While overall genetic diversity has rarely been successfully related to environmental conditions, genetically based changes in traits have now been linked to the presence of toxins and both local and global temperature shifts. Candidate loci for monitoring stressors are emerging from information on how specific genes influence traits, and from screens of random loci across environmental gradients. Drosophila research suggests that chromosomal regions under recent intense selection can be identified from patterns of molecular variation and a high frequency of transposable element insertions. Allele frequency changes at candidate loci have been linked to pesticides, pollutants and climate change. Nevertheless, there are challenges in interpreting allele frequencies in populations, particularly when a large number of loci control a trait and when interactions between alleles influence trait expression. To meet these challenges, population samples should be collected for longitudinal studies, and experimental programmes should be undertaken to link variation at candidate genes to ecological processes.
Thirty years of plant transformation technology development
Authors: Vain Philippe
Published: November 2006

Technology development is seminal to many aspects of basic and applied plant transgenic science. Through the development and commercialization of genetically modified crops, the evolution of plant transgenic technologies is also relevant to society as a whole. In this study, literature statistics were used to uncover trends in the development of these technologies. Publication volume and impact (citation) over the past 30 years were analysed with respect to economic zones, countries, species and DNA delivery method. This revealed that, following a dramatic expansion in the 1980s, publications focusing on the development of transgenic technology have been slowing down worldwide since the early mid‐1990s, except in a few leading Asian countries. The implications of these trends on the future of plant transgenic science as a whole are discussed.
PUBLIC ADMINISTRATION IN THE NETHERLANDS: EXPANSION, DIVERSIFICATION AND CONSOLIDATION
Authors: KICKERT WALTER J.M. , TOONEN THEO A.J.
Published: November 2006

The rise of Dutch administrative sciences is related to the post‐war expansion of the country’s welfare state. The growing welfare state needed scientific support for policy‐making and planning. Legal expertise alone was no longer sufficient. After the initial separation from administrative law, the post‐war policy and administrative sciences in The Netherlands were strongly oriented towards our American ‘big brother’. Since the 1980s, a growing self‐identity and self‐confidence has developed. The period from the late 1970s to the mid 1990s witnessed a steady expansion and diversification of Dutch PA sciences. The subject is now taught at 11 of the 13 Dutch universities. The enormous growth of the early 1990s is over, and student numbers have now stabilized – and at a substantial level, thus consolidating the position of PA departments in most universities. From the mid 1990s onwards Dutch administrative sciences have gone through a process of internationalization. Dutch PA sciences have as a result acquired a status of recognized quality in the international scientific community.
PUBLIC AND PRIVATE SECTOR MANAGERS OVER 20 YEARS: A TEST OF THE ‘CONVERGENCE THESIS’
Authors: POOLE MICHAEL , MANSFIELD ROGER , GOULD‐WILLIAMS JULIAN
Published: November 2006

This paper sets out to test the ‘convergence thesis’ in respect of managers in the public and private sectors in Britain. New Public Management (NPM) initiatives have had the objective of making managerial behaviour in public sector organizations more similar to that in the private sector. Based on unique national surveys undertaken in 1980, 1990 and 2000, using quite large random samples of fellows and members of the Chartered Management Institute (CMI), comparisons are made to investigate whether ‘convergence’ between public and private sector managers has actually occurred. The patterns are found to be complex and, although there are some signs of convergence, the two sectors continue to exhibit similarities, persistent differences and parallel movements evident in managerial attitudes, behaviour and experiences.
Collinsia sparsiflora in serpentine and nonserpentine habitats: using F2 hybrids to detect the potential role of selection in ecotypic differentiation
Authors: Wright Jessica W. , Stanton Maureen L.
Published: November 2006

Here we document phenotypic differences between serpentine and nonserpentine ecotypes of Collinsia sparsiflora, as well as patterns of selection in these contrasting soil habitats.

We transplanted the two parental ecotypes and experimental F2 hybrids into six field sites, and collected morphological, phenological and fitness data on emergent plants. To focus on edaphically mediated selection, rather than on pollinator‐mediated selection, we used pollinator‐exclusion cages.

Transplanted parentals of the two ecotypes showed genetic differentiation for floral traits, but not for phenological traits or cotyledon size. For the F2 hybrids growing on serpentine soils, there was significant directional selection on cotyledon size, flower size and flower shape. However, the pattern of selection did not differ significantly between serpentine and nonserpentine sites.

Overall, we did not see evidence for divergent selection on the two soil types. We conclude that differences in floral traits between the ecotypes do not reflect adaptation to physical conditions associated with soil type, and that there are unmeasured traits that must be contributing to ecotypic differentiation.
Blockade of Cue‐induced Brain Activation of Abstinent Alcoholics by a Single Administration of Amisulpride as Measured With fMRI
Authors: Hermann Derik , Smolka Michael N. , Wrase Jana , Klein Sabine , Nikitopoulos Jörg , Georgi Alexander , Braus Dieter F. , Flor Herta , Mann Karl , Heinz Andreas
Published: November 2006

Background: Once alcohol dependence is established, alcohol‐associated cues may induce dopamine release in the reward system, which is accompanied by alcohol craving and may lead to relapse. In cocaine addicts, dopamine release in the thalamus was positively correlated with cocaine craving. We tested the effects of the atypical dopamine D2/3 blocker amisulpride on cue‐induced brain activation in a functional magnetic resonance imaging (fMRI) paradigm.

Methods: Alcohol‐associated and neutral pictures were presented in a block design to 10 male abstinent alcoholics (1–3 weeks after detoxification) and 10 healthy men during fMRI. The fMRI scans were acquired before and 2 hours after the oral application of 400 mg amisulpride. Before and after each scan, alcohol craving was measured with visual analogue scales.

Results: Before the application of amisulpride, alcohol versus control cues elicited a higher blood oxygen level–dependent (BOLD) signal in the left frontal and orbitofrontal lobe, left cingulate gyrus, bilateral parietal lobe, and bilateral hippocampus in alcoholics compared with healthy controls. After amisulpride, alcoholics showed a reduced activation in the right thalamus compared with the first scan. Alcoholics no longer showed significant differences in their cue‐elicited BOLD response after amisulpride medication compared with medication‐free controls. Self‐reported craving was not affected by amisulpride medication.

Conclusions: Amisulpride medication was associated with reduced cue‐induced activation of the thalamus, a brain region closely connected with frontostriatal circuits that regulate behavior and may influence relapse risk.
Management of Cerebral Spinal Fluid Leak Complicating Spinal Cord Stimulator Implantation
Authors: Eldrige Jason S. , Weingarten Toby N. , Rho Richard H.
Published: November 2006

Abstract:  Accidental puncture of the dura mater with resultant leakage of cerebral spinal fluid (CSF) and development of postdural puncture headache (PDPH) is a known potential complication of percutaneous placement of spinal cord stimulator (SCS) leads. However, the implications and management strategies for this complication have not been thoroughly reported. We report two cases of SCS lead placement complicated by CSF leak and PDPH.
Prevalence of Contraindicated Medical Conditions and Use of Precluded Medications in Patients with Painful Neuropathic Disorders Prescribed Amitriptyline
Authors: Gore Mugdha , Dukes Ellen , Rowbotham David , Tai Kei‐Sing , Leslie Douglas L.
Published: November 2006

Abstract: Amitriptyline is a tricyclic antidepressant that is historically indicated and used to manage depression. More recently, due to clinical evidence demonstrating efficacy, it is often prescribed in the management of painful neuropathic disorders (PNDs). However, the amitriptyline label contains numerous preclusions (contraindications, warnings/precautions, drug interactions). Our objective was to measure the frequency of amitriptyline prescriptions in PND patients using the U.K. General Practice Research Database and assess whether any prescriptions were given to patients with preclusions listed in the product label. We identified a total of 13,546 patients (mean age 59 ± 16.2 years; 66.7% female) who had a diagnosis of a PND and received ≥1 prescription for amitriptyline between July 1998 and June 2001. Nearly half (46.7%) of PND patients prescribed amitriptyline had ≥1 preclusion for its use; 3.5% had ≥1 contraindication; 22% had ≥1 warning/precaution; and 33% received ≥1 medication with a potential for drug interactions with amitriptyline. Preclusions were more likely in women than in men (48.3% vs. 43.4%,P < 0.0001); their incidence increased with age (42.8%, 50.4%, 55.1%, and 52.3% among those ages <65, 65–74, 75–84, and 85+ years,P < 0.0001), and the number of patients with preclusions was the highest in the phantom limb pain group (67.4%) and lowest in the atypical facial pain group (42.9%),P < 0.001. The average daily amitriptyline doses (starting: 33.6 ± 32.4 mg; maintenance: 42.1 ± 39.9 mg) were low compared to those used for the treatment of depression. Results indicate that, in a significant number of cases, the existence of preclusions did not prevent the prescribing of amitriptyline. Our findings raise a potential concern about the way this medication is being used. However, the clinical significance of these data is, as yet, unclear. Although, in theory, adverse outcomes may have been associated with this practice, we could not confirm this with this database analysis.
Constrained Sintering of Silver Circuit Paste
Authors: Lin Yun‐Chiang , Jean Jau‐Ho
Published: November 2006

Densification kinetics and stress development during constrained sintering of a silver film on a rigid silicon substrate have been studied. Compared with free sintering, the sintering of constrained silver film exhibits a much lower densification and slower densification kinetics. The densification‐controlled mechanism changes from fast grain‐boundary diffusion kinetics for free sintering to slow lattice diffusion kinetics for constrained sintering. The in‐plane tensile stress developed during constrained sintering of silver film, measured using a noncontact laser‐scanning optical system, increases rapidly to a maximum level of 1.0–1.5 MPa initially, gradually decreases, and then becomes constant at 0.8–1.0 MPa. The maximum stress observed increases with increasing sintering temperature as a result of the faster densification rate. It is believed that the retardation of densification kinetics of constrained silver film is caused by a change in densification mechanism and the existence of in‐plane tensile stress.
Zirconia Nanoparticles Made in Spray Flames at High Production Rates
Authors: Mueller Roger , Jossen Rainer , Pratsinis Sotiris E. , Watson Mark , Akhtar M. Kamal
Published: November 2006

Synthesis of zirconia nanoparticles by flame spray pyrolysis (FSP) at high production rates is investigated. Product powder is collected continuously in a baghouse filter unit that is cleaned periodically by air‐pressure shocks. Nitrogen adsorption (BET), X‐ray diffractometry (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) are used to characterize the product powder. The effect of powder production rate (up to 600 g/h), dispersion gas flow rate, and precursor concentration on product particle size, crystallinity, morphology, and purity is investigated. The primary particle size of zirconia is controlled from 6 to 35 nm, while the crystal structure consists of mostly tetragonal phase (80–95 wt%), with the balance monoclinic phase at all process conditions. The tetragonal crystal size is close to the primary particle size, which indicates weak agglomeration of single crystals.
Method for Obtaining the Full Set of Linear Electric, Mechanical, and Electromechanical Coefficients and All Related Losses of a Piezoelectric Ceramic
Authors: Algueró Miguel , Alemany Carlos , Pardo Lorena , González Amador M.
Published: November 2006

A method based on the use of four piezoelectric resonances for three sample geometries is presented that allows one to obtain all the dielectric permittivities, compliances, and piezoelectric coefficients of a piezoelectric ceramic in complex form and, therefore, all related losses. Piezoelectric losses are responsible for heat generation and hysteresis in actuators. The method is applied to a Navy type II PZT‐based piezoelectric ceramic (PZT = lead zirconate titanate), for which the full set of linear electric, mechanical, and electromechanical coefficients is given in complex form. Full sets of coefficients for the available piezoceramics are required for exploiting all the possibilities of finite element analysis, both in fundamental research (mechanisms of degradation) and in development (element design). This numerical technique is necessary to explore arbitrary shapes provided by solid free‐form‐fabrication technologies.
Degradation of Bioactive Polydimethylsiloxane–CaO–SiO2–TiO2 and Poly(tetramethylene oxide)–CaO–TiO2 Hybrids in a Simulated Body Fluid
Authors: Kamitakahara Masanobu , Kawashita Masakazu , Miyata Noboru , Kokubo Tadashi , Nakamura Takashi
Published: November 2006

It has been shown that polydimethylsiloxane (PDMS)–CaO–SiO2–TiO2 and poly(tetramethylene oxide) (PTMO)–CaO–TiO2 hybrids form apatite on their surfaces in a simulated body fluid (SBF) and show mechanical properties similar to those of human cancellous bones. In the present study, changes, caused by soaking in SBF, were measured in the mechanical properties of PDMS–CaO–SiO2–TiO2 hybrids with different CaO and TiO2 contents and PTMO–CaO–TiO2 hybrids with different CaO contents. Significant decreases in the strength and strain at failure of the hybrids were observed for the PDMS–CaO–SiO2–TiO2 hybrids with high CaO or TiO2 contents and PTMO–CaO–TiO2 hybrids with a high CaO content after soaking in SBF for 4 w. This indicates that incorporation of a large amount of CaO component into the hybrids should result in the deterioration of the hybrids in the body environment.
Suitable Glass‐Ceramic Sealant for Planar Solid‐Oxide Fuel Cells
Authors: Sohn Sung‐Bum , Choi Se‐Young , Kim Gyeung‐Ho , Song Hue‐Sup , Kim Goo‐Dae
Published: November 2006

Various glass‐ceramics were prepared based on the BaO–Al2O3–B2O3–SiO2 system with the addition of La2O3, ZrO2, or NiO in an attempt to develop a suitable sealant for planar solid‐oxide fuel cells operating at 800°C. To estimate the applicability of these glasses as suitable sealants, their thermal and chemical stabilities as well as the crystallization behavior and bonding characteristics of their parent glasses were investigated. The thermal properties and crystallization behavior of the parent glasses were dependent on the type of additive used, and the bonding characteristics were strongly influenced by the B2O3/SiO2 value in the glass composition. Observation of microstructural change and chemical reaction at the glass‐ceramic/electrolyte interface confirmed that the prepared glass‐ceramics possessed long‐term stability during heat treatment at the operation temperature for up to 1000 h.
Depth‐Resolved Porosity Investigation of EB‐PVD Thermal Barrier Coatings Using High‐Energy X‐rays
Authors: Kulkarni Anand A. , Herman Herbert , Almer Jon , Lienert Ulrich , Haeffner Dean , Ilavsky Jan , Fang Stacy , Lawton Paul
Published: November 2006

Demands for designing prime reliant, energy‐efficient, and high‐performance thermal barrier coatings (TBCs) in gas turbines have led to a growing interest toward comprehensive microstructural characterization. Here we investigate the novel use of high‐energy X‐rays for small‐angle X‐ray scattering (SAXS), together with wide‐angle scattering and radiography, for the depth‐resolved characterization of TBCs grown by electron beam physical vapor deposition (EB‐PVD). The coating microstructure is found to consist of columns perpendicular to the substrate, extending through the thickness, with a [001] growth texture and significant intercolumnar porosity. In addition, overshadowing effects during deposition together with gas entrapment give rise to nanoscale intracolumnar porosity consisting of featherlike and globular pores. Radiography showed an increase in the total porosity, from 15% near the substrate to 25% near the coating surface, which is ascribed to an increase in the intercolumnar spacing at the top of the coating. By contrast, the small‐angle scattering studies, which are sensitive to fine features, showed the pore internal surface area to be greatest near the substrate.
Spark Plasma Sintering (SPS) of NASICON Ceramics
Authors: Lee Ji‐Sun , Chang Chae‐Myung , Lee Young IL , Lee Jong‐Heun , Hong Seong‐Hyeon
Published: November 2006

Spark plasma sintering (SPS) method was used to obtain dense NASICON ceramics with a high‐electrical conductivity, which was compared with conventional solid‐state sintering. The fully dense NASICON was achieved at a relatively low‐sintering temperature of 1100°C, whereas the apparent density of the specimen prepared by conventional sintering was 74% of the theoretical density. The highest conductivity of 1.8 × 10−3 Scm−1 at 25°C, which is comparable to the best value reported, was achieved using the SPS process. Considering the phase, density, and microstructure, it appears that there is more room for improved conductivity by controlling the amount of monoclinic zirconia and the resistive grain‐boundary glass phase.
Microwave Drilling of Ceramic Thermal‐Barrier Coatings
Authors: Jerby Eli , Thompson A. Mark
Published: November 2006

The microwave drill is a novel process for creating shaped holes in nonconductive materials. Its inherent material selectivity makes the microwave drill ideally suited for the controlled removal of ceramic coatings from underlying metallic substrates. In this paper, it is shown that the microwave drill process can drill through ceramic thermal barrier coatings (TBCs) to uncover an array of simulated cooling holes. The concept, apparatus, and procedure for successful drilling are described, and the potential for use in the production of advanced gas turbine components is discussed.
Mechanical Activation of Tetracalcium Phosphate
Authors: Gbureck Uwe , Barralet Jake E. , Hofmann Michael , Thull Roger
Published: November 2006

It was found that prolonged high‐energy ball‐milling of Hilgenstokite (tetracalcium phosphate, TTCP) resulted in a decrease in both particle and crystallite size, leading to a mechanical activation of the compound. This mechanically activated material demonstrated a high reactivity such that, in contrast to highly crystalline TTCP, a setting reaction with water to nanocrystalline hydroxyapatite (HA) and Ca(OH)2 could be achieved at 37°C. However, crystalline TTCP is practically unreactive at physiologic temperatures because of the formation of a thin HA layer on the particle surface preventing further reaction.
Development of WC–ZrO2 Nanocomposites by Spark Plasma Sintering
Authors: Basu Bikramjit , Lee Jong‐Heun , Kim Doh‐Yeon
Published: November 2006

In the present work, we report the processing of ultrahard tungsten carbide (WC) nanocomposites with 6 wt% zirconia additions. The densification is conducted by the spark plasma sintering (SPS) technique in a vacuum. Fully dense materials are obtained after SPS at 1300°C for 5 min. The sinterability and mechanical properties of the WC–6 wt% ZrO2 materials are compared with the conventional WC–6 wt% Co materials. Because of the high heating rate, lower sintering temperature, and short holding time involved in SPS, extremely fine zirconia particles (∼100 nm) and submicrometer WC grains are retained in the WC–ZrO2 nanostructured composites. Independent of the processing route (SPS or pressureless sintering in a vacuum), superior hardness (21–24 GPa) is obtained with the newly developed WC–ZrO2 materials compared with that of the WC–Co materials (15–17 GPa). This extremely high hardness of the novel WC–ZrO2 composites is expected to lead to significantly higher abrasive‐wear resistance.
Results of the PETHEMA ALL‐96 trial in elderly patients with Philadelphia chromosome‐negative acute lymphoblastic leukemia
Authors: Sancho Juan‐Manuel , Ribera Josep‐Maria , Xicoy Blanca , Morgades Mireia , Oriol Albert , Tormo Mar , Potro Eloy del , Debén Guillermo , Abella Eugenia , Bethencourt Concepción , Ortín Xavier , Brunet Salut , Ortega‐Rivas Fernando , Novo Andrés , López Ramón , Hernández‐Rivas Jesús‐María , Sanz Miguel‐Angel , Feliu Evarist ,   on behalf of the PETHEMA Group, Barcelona, Spain
Published: November 2006

Background and aim: Only 20–30% of elderly patients with acute lymphoblastic leukemia (ALL) are enrolled in clinical trials because of co‐morbid disorders or poor performance status. We present the results of treatment of Philadelphia chromosome‐negative (Ph−) ALL patients over 55 yr treated in the PETHEMA ALL‐96 trial. Patients and methods: From 1996 to 2006, 33 patients 55 yr with Ph− ALL were included. Induction therapy was vincristine, daunorubicin, prednisone, asparaginase, and cyclophosphamide over 5 weeks. Central nervous system (CNS) prophylaxis involved triple intrathecal (IT) therapy, 14 doses over the first year. Consolidation‐1 included mercaptopurine, methotrexate, teniposide and cytarabine, followed by one consolidation‐2 cycle similar to the induction cycle. Maintenance consisted of mercaptopurine and methotrexate up to 2 yr in complete remission (CR) with monthly reinduction cycles (vincristine, prednisone and asparaginase) during the first year. Results: Median (range) age was 65 yr (56–77). Phenotype (30 patients): early‐pre‐B 7, common/pre‐B 18, T 5. Cytogenetics (28 patients): normal 12, complex 10, t(4;11) 2 and other 4. CR was achieved in 19/33 (57.6%) patients, early death occurred in 12 (36.4%) and 2 (6%) were resistant. Overall survival and disease‐free survival probabilities (2 yr, 95% CI) were 39% (21%–57%) and 46% (22%–70%), respectively (median follow up of 24 months). Removal of asparaginase and cyclophosphamide from the induction decreased induction death (OR 0.119, CI 95% 0.022–0.637, P = 0.013) and increased survival (20% vs. 52%, P = 0.05). Conclusions: The prognosis of elderly Ph− ALL patients is poor. In this study, less intensive induction decreased toxic death, allowing delivery of planned consolidation therapy and increased survival probability.
Tumor necrosis factor promoter gene polymorphism associated with increased susceptibility to non‐Hodgkin's lymphomas
Authors: Bel Hadj Jrad Besma , Chatti Amel , Laatiri Adnene , Ahmed Slim Ben , Romdhane Abdelaziz , Ajimi Salem , Chouchane Lotfi
Published: November 2006

The tumor necrosis factor (TNF) is a pro‐inflammatory cytokine involved in the severity of different immune‐regulated diseases including autoimmune, infectious, and malignant diseases. Chronic immune system stimulation could be a potential etiologic factor in these diseases. Given the determining role of TNF acting early in the immune response, we investigated the effect of an inherited genetic polymorphism at TNF promoter (−308A/G) on a predisposition to non‐Hodgkin's lymphoma (NHL). The genotype distribution was determined in 194 patients with NHL and 160 age‐ and sex‐matched population‐based controls. The comparison of the −308TNF genotypes between the NHL patients and the controls showed a significant excess of A/A genotype that is previously associated with higher TNF production. Indeed, the A/A genotype is present in 7.7% of the cases, but in only 2.5% of the controls. This genotype is associated with a significant increased risk of NHL (odds ratio = 3.63, P = 0.028). These results indicate that the genetic polymorphism which could lead to an increased TNF production or a neighboring gene within the MHC region may influence the susceptibility to NHL in Tunisian population. Other epidemiologic studies carried out in both the Tunisian population and elsewhere are needed to confirm this finding.
Fall about laughing: A case of laughter syncope
Authors: Bragg Matthew J
Published: November 2006

Laughter syncope is an unusual but recognized form of situational syncope likely to have a similar pathophysiological origin to tussive syncope. There are few case reports of this syndrome in the literature. Patients, as in this case, might present initially to the ED, and laughter should be considered among the numerous differentials for syncope.
State of play: Clearing the thoracolumbar spine in blunt trauma victims
Authors: Howes Marten C , Pearce Andrew P
Published: November 2006

Introduction:  The present article reviews the clinical and imaging clearance of the thoracic and lumbar spines of blunt trauma victims and the evolution of these strategies with the use of new imaging technologies.

Methods:  A comprehensive literature search was performed, and articles identified were critically appraised

Results:  Twenty papers were identified, 12 directly comparing computed tomography screening with plain X‐rays. Evidence‐based protocols are presented. The evolution of imaging strategies in response to new technology is described.

Conclusions:  Thoracolumbar spine screening is best done using reformatted images acquired when scanning the chest and abdomen of high‐risk multi‐trauma patients. If computed tomography is not clinically indicated for investigation of other injuries then plain films are the first line investigation.
Development and implementation of an education and credentialing programme to provide safe paediatric procedural sedation in emergency departments
Authors: Babl Franz , Priestley Stephen , Krieser David , Miller Joanne , Tully Melissa , Spicer Maureen , McGowan Vicki , Dilla Natashia
Published: November 2006

Objective: In the conduct of paediatric procedural sedation (PPS) within the ED the combination of powerful drugs, variable competency levels and high staff turnover carry the potential for sedation‐associated adverse events. Yet, currently, there is no set programme for education and accreditation of ED staff in PPS. We set out to develop such a programme.

Methods: We outline the development process of a comprehensive multidisciplinary PPS programme and present its key educational elements (sedation manual, lecture, treatment order form and checklist, parent information handout) and credentialing through multiple‐choice questions and competency assessments. We describe issues associated with the implementation of the programme at a metropolitan mixed ED and the ED of a major tertiary paediatric centre.

Results: Since its inception a total of 294 emergency staff have either completed or have partially completed the programme. Staff feedback showed that the majority of staff scored the elements of the programme as very good to excellent, and felt that their sedation skills had improved and their practice was safer. The development and implementation of the PPS programme raised many issues and posed a number of challenges. We describe the strategies we used to overcome such challenges and barriers.

Conclusion: We present the development and implementation of a comprehensive PPS programme for emergency staff. As a result of the multicentre development process involving a community and a tertiary paediatric ED the programme will likely have broad applicability in different types of ED caring for children.
Avian influenza: A pandemic waiting in the wings?
Authors: Hampson Alan W
Published: November 2006

Recent widespread outbreaks of avian influenza and, associated with these a growing number of human infections with a high mortality rate, have raised concerns that this might be the prelude to a severe pandemic of human influenza. As a background to these concerns the present article reviews influenza as a human disease, its origins and the involvement of other species, properties of the influenza viruses and the current status of influenza prevention and control.