bluuebunny/crossref_metadata_2025 huggingface dataset:
The levels of measles antibodies in Nigerian children aged 0–12 months and its relationship with maternal parity
Authors: Eghafona N. O. , Ahmad A. A. , Odama L. E. , Onuora C. , Gosham L. T. , Emejuaiwe S. O. , Woghiren E. I.
Published: October 2009

Six hundred and fifty-seven children aged between 0 and 12 months were randomly chosen and studied for measles antibody titres by the haemagglutination inhibition (HAI) test. The results showed significant variations in HAI antibody titres. Children between 0–3 months showed high measles HAI antibody titres which declined to a trough between 4 and 0 months. A rise in HAI antibody titre was observed from 10 to 12 months age. Multiparity and higher age in the mothers were noted as probable factors influencing the titres of measles HAI antibody in children. The results indicated that with increased maternal parity, measles HAI antibody titres in the children declined.
Shigellosis due to occupational contact with non-human primates
Authors: Kennedy F. M. , Astbury J. , Needham J. R. , Cheasty T.
Published: October 2009

A small cluster of dysenteric illness, due to Shigella flexneri, was identified among technical assistants of a primate research unit. All of the affected individuals had been in regular contact with a colony of cynomolgus macaque monkeys, one of which was known to have suffered from acute haemorrhagic colitis in the preceding few weeks. Four monkeys were found to be excreting S. flexneri bacilli of identical antigen type (lb) to that isolated from the human cases. Investigation of working practices revealed the potential for inadvertent faecooral spread and the need to improve existing control methods. We conclude that this small outbreak of shigellosis represents a primate-associated occupational zoonosis. The risk may not be fully appreciated by handlers or their doctors.
Adherence to HEp-2 cells and enteropathogenic potential of Aeromonas spp.
Authors: Grey P. A. , Kirov S. M.
Published: October 2009

Aeromonas strains (total = 60) of clinical, water and food origin were tested for adherence to HEp-2 cells. Environmental strains were selected (except for A. caviae) to include primarily those expressing other virulence-associated properties. Adhesion was markedly species-dependent (A. veronii biotype sobria, 15 of 20 [58%], A. caviae, 4 of 12 [33%] and A. hydrophila, 2 of 8 [11%]). A. veronii biotype sobria were adhesive, irrespective of source (62 and 54% for clinical and environmental strains, respectively). Adherent strains of this species were enterotoxin-positive and most (13 of 15) grew at 43 °C. A. caviae isolated from clinical specimens contained a higher proportion (75%) of adherent strains than environmental strains (13%). Virulent subsets of A. veronii biotype sobria and A. caviae are adherent to HEp-2 cells. The HEp-2 assay is a useful model for investigating mechanisms of adherence and enteropathogenicity of virulent Aeromonas species.
Different seroprevalences of antibodies against Neisseria meningitidis serogroup A and Haemophilus influenzae type b in Sudanese and Swedish children
Authors: Salih M. A. M. , Fredlund H. , Hugosson S. , Bodin L. , Olcén P.
Published: October 2009

Sampling of sera from 202 Sudanese and 124 Swedish children 1–14 years of age was conducted at the end of the 1980s presenting an opportunity to compare the seroprevalence of anti-Neisseria meningitidis (MC) serogroup A antibodies in an area immediately before outbreak of an epidemic (Sudan 1988) with a low endemic area (Sweden). An ELISA antibody assay was developed for detection of antibodies against capsular polysaccharide of MC serogroup A and Haemophilus influenzae type b (Hib). Serum antibody against MC serogroup A was found significantly more frequently in Sudanese than in Swedish children. This indicates that factors other than herd immunity, as measured by serum antibodies against MC serogroup A polysaccharide, are important for avoidance of an MC serogroup A epidemic. The seroprevalence of Hib antibodies was, in contrast, significantly higher in Swedish than in Sudanese children, especially for 5–9-year-old children. A possible explanation may be the different systems of day-care of children in the two countries.
The age of infection with varicella-zoster virus in St Lucia, West Indies
Authors: Garnett G. P. , Cox M. J. , Bundy D. A. P. , Didier J. M. , Catharine J. St.
Published: October 2009

Sera from an age-stratified sample of 1810 people from the Caribbean island of St Lucia were tested for antibodies against varicella-zoster virus. The results indicate that very few infections occur in childhood, which agrees with clinical survey data from other tropical countries, but contrasts with the observed high case rate in children in temperate countries. The alternative hypotheses which may explain these results are discussed, and it is suggested that high ambient temperatures interfere with the transmission of the virus. Irrespective of the cause, the pattern of varicella incidence observed has important implications for any vaccination policy adopted in tropical countries.
Staphylococcus aureus strains of type 95. Spread of a single clone
Authors: Rosdahl V. T. , Witte W. , Musser M. , Jarløv J. O.
Published: October 2009

Staphylococcus aureus strains of type 95 in Denmark have increased to a frequency of 20% of the total S. aureus population. A clonal origin and possible subdivision of these strains have been discussed. In the present investigation 35 epidemiologically unrelated S. aureus strains of type 95 as well as reference strains of other types have been analysed by other typing techniques including lectintyping, multilocus enzyme electrophoresis and pulsed-field gel electrophoresis of genomic restriction fragments. No subdivision could be achieved based on any of these methods and a clonal origin seems therefore possible.
Seroepidemiology of cryptosporidiosis in children in Papua New Guinea and Australia
Authors: Groves V. J. , Lehmann D. , Gilbert G. L.
Published: October 2009

Enzyme immunoassays (EIA) were used to measure serum antibodies to Cryptosporidium in four immunocompetent adults with recent proven cryptosporidial infection, 379 healthy children and 73 adult volunteers in Melbourne, Australia, and 205 children in Papua New Guinea (PNG) (47 healthy children; 158 with pneumonia). Antibodies peaked 3–6 weeks after infection and fell to baseline within a few months. A high level (5000 EIA units/ml) or a significant change between paired sera, of IgG or IgM, were taken as evidence of recent infection and found in 24% of PNG children and in 8% of children and 5% of adults in Melbourne. Among PNG children with pneumonia who had high cryptosporidial antibody levels, those with measles (6/8) were significantly more likely (P = 0·002) to have diarrhoea than the remainder (4/28). Symptomatic cryptosporidiosis may be associated with transient immune suppression due to viral infection. This study indicates that serological surveys can contribute to an understanding of the epidemiology of cryptosporidosis.
The Epidemiology of bat rabies in New York State, 1988–92
Authors: Childs J. E. , Trimarchi C. V. , Krebs J. W.
Published: October 2009

In 1993 New York and Texas each reported a human rabies case traced to a rare variant of rabies virus found in an uncommon species of bat. This study examined the epidemiology of bat rabies in New York State. Demographic, species, and animal-contact information for bats submitted for rabies testing from 1988–92 was analysed.

The prevalence of rabies in 6810 bats was 4·6%. Nearly 90% of the 308 rabid bats identified to species were the common big brown bat(Eptesicus fuscus), which comprised 62% of all submissions. Only 25 submissions were silver-haired bats(Lasionycterus noctivagans), the species associated with the two 1993 human cases of rabies, and only two of these bats were positive. Rabies was most prevalent in female bats, in bats submitted because of human or animal contact, and in animals tested during September and October.

These results highlight the unusual circumstances surrounding the recent human rabies cases in the United States. A species of bat rarely encountered by humans, and contributing little to the total rabies cases in bats, has been implicated in the majority of the indigenously acquired human rabies cases in the United States. The factors contributing to the transmission of this rare rabies variant remain unclear.
Hepatitis C virus infection in Iceland: a recently introduced bloodborne disease
Authors: Löve A. , Stanzeit B.
Published: October 2009

This study demonstrates a very high prevalence of antibodies to hepatitis C virus among Icelandic intravenous (i.v.) drug users. Of 152 identified i.v. drug users 95 (63%) were shown to have antibodies to the hepatitis C virus. In contrast the seroprevalence in the general Icelandic population is low, (0·2%). Almost all cases of hepatitis C virus infection in Iceland are due to i.v. drug use or to use of infected blood or blood products. Sporadic cases with unexplained modes of transmission, a significant portion of hepatitis C infections elsewhere, are virtually non-existent in Iceland. The results of this study are consistent with the hypothesis that the sporadic community-acquired cases could be caused by blood transfer due to bites from insect vectors such as mosquitoes which are not found in Iceland.
Tobacco smoking in older people
Authors: Allen SC
Published: October 2009

Smoking remains prevalent in elderly people in the UK and similar countries. The adverse health effects of current smoking continue to accumulate in old age and stopping smoking in old age confers benefits on function, morbidity and mortality. Many elderly people wish to stop smoking and many are successful. Structured support from health and social care workers improves quit rates and nicotine replacement therapy can be an effective aid to smoking cessation in old age. Doctors and other healthcare staff should use the opportunities of patient contact to encourage older smokers to quit. Cognitive impairment is a barrier to successful smoking cessation.
Two chants in the Byzantine Rite for Holy Saturday
Authors: Harris Simon
Published: October 2009

Among the ten celebrations of the Mass of St Basil in the Orthodox Church during the year are the conclusions to the three Vesper services immediately before the three major feasts of Christmas, Epiphany and Easter. Two of these Vesper services – those for Christmas Eve and the Eve of Epiphany – are of particular musical interest since they contain psalms with troparia or antiphons, for both of which the entire music can be transcribed from thirteenth-century manuscripts, so that these two services can be celebrated with what are, almost certainly, the oldest known complete examples of Byzantine psalm singing. From a recent paper of mine on these psalms, it can be gathered that they are examples of what is known as ‘responsorial psalmody’, the psalm itself being sung by a soloist, and the attached troparion by a choir of trained singers or psaltae. In both services they occur as punctuations of a series of readings, appearing in each case after the third and the sixth reading. On the Eve of Epiphany we should perhaps expect to find further psalms after the ninth and twelfth readings, since the series extends to thirteen readings in modern service books and to twelve in the early Middle Ages; yet no such psalms appear now or seem ever to have been sung at this point. And similarly, on Holy Saturday, when according to the ancient Jerusalem cursus twelve readings were given, to be extended in Constantinople to fifteen, no equivalents seem to have been performed at any point.
White matter diffusivity predicts memory in patients with subjective and mild cognitive impairment and normal CSF total tau levels
Authors: GRAMBAITE RAMUNE , STENSET VIDAR , REINVANG IVAR , WALHOVD KRISTINE B. , FJELL ANDERS M. , FLADBY TORMOD
Published: October 2009

Subjective and mild cognitive impairment (SCI and MCI) are etiologically heterogeneous conditions. This poses problems for assessment of pathophysiological mechanisms and risk of conversion to dementia. Neuropsychological, imaging, and cerebrospinal fluid (CSF) findings serve to distinguish Alzheimer’s disease (AD) and other etiological subgroups. Tau-molecules stabilize axonal microtubuli; high CSF total tau (T-tau) reflects ongoing axonal damage consistent with AD. Here, we stratify patients by CSF T-tau pathology to determine if memory network diffusion tensor imaging (DTI) predicts memory performance in the absence of elevated T-tau. We analyzed neuropsychological test results, hippocampus volume (HcV) and white matter diffusivity in 45 patients (35 with normal T-tau). The T-tau pathology group showed more hippocampus atrophy and memory impairment than the normal T-tau group. In the T-tau normal group: (1) memory was related with white matter diffusivity [fractional anisotropy (FA) and radial diffusivity (DR)], and (2) FA of the genu corpus callosum was a unique predictor of variance for verbal learning, and HcV did not contribute to this prediction. The smaller sample size in the T-tau pathology group precludes firm conclusions. In the normal T-tau group, white matter tract and memory changes may be associated with normal aging, or with non-tau related pathological mechanisms. (JINS, 2010,16, 58–69.)
Cognitive reserve as a moderator of postconcussive symptoms in children with complicated and uncomplicated mild traumatic brain injury
Authors: FAY TARYN B. , YEATES KEITH OWEN , TAYLOR H. GERRY , BANGERT BARBARA , DIETRICH ANN , NUSS KATHRYN E. , RUSIN JEROME , WRIGHT MARTHA
Published: October 2009

The occurrence of postconcussive symptoms (PCS) following mild traumatic brain injury (TBI) in children may depend on cognitive reserve capacity. This prospective, longitudinal study examined whether the relationship between mild TBI and PCS is moderated by cognitive ability, which served as a proxy for cognitive reserve. Participants included 182 children with mild TBI and 99 children with orthopedic injuries (OI), ranging from 8 to 15 years of age when injured. Mild TBI were classified as complicated (n= 32) or uncomplicated (n= 150) depending on whether they were associated with trauma-related intracranial abnormalities on magnetic resonance imaging. PCS were assessed initially within 3 weeks of injury, and again at 1, 3, and 12 months post injury. The initial assessment also included standardized tests of children’s cognitive skills and retrospective parent ratings of pre-injury symptoms. Hierarchical linear modeling indicated that ratings of PCS were moderated jointly by cognitive ability and injury severity. Children of lower cognitive ability with a complicated mild TBI were especially prone to cognitive symptoms across time according to parents and to high acute levels of PCS according to children’s self-ratings. Cognitive reserve is an important moderator of the outcomes of mild TBI in children and adolescents. (JINS, 2010,16, 94–105.)
The grammaticalization and subjectification of adverbial -ingclauses (converb clauses) in English
Authors: KILLIE KRISTIN , SWAN TORIL
Published: October 2009

The present article discusses the development of adverbial -ingclauses, so-called ‘converb clauses’, in English. We argue that Middle English does not have a category of truly subordinate adverbial clauses in -ing, but that such clauses have developed on the basis of semi-coordinate -ingclauses denoting an accompanying circumstance or exemplification/specification. In the course of the Middle English period, such clauses began to be reinterpreted as clauses expressing adverbial relations such as time, condition, cause, purpose, etc. Another likely source of converb clauses is participial relative clauses. We see the development of converb clauses as an instance of grammaticalization, as it involves the development of a grammatical means of expressing a rhetorical function, viz. the ‘Nucleus-Satellite’ relation (Mathiessen & Thompson 1988). This grammaticalization process also involves subjectification, given that the source constructions are propositional, while time and cause clauses have textual and expressive functions/meanings. The grammaticalization process was probably also fed by other participial structures – notably the progressive and the gerund, which were being grammaticalized at the same time – and also nonclausal adverbial structures.
Shetland Scots as a new dialect: phonetic and phonological considerations
Authors: KNOOIHUIZEN REMCO
Published: October 2009

The dialect of Scots spoken in the Shetland Islands has been variously described as a language shift variety, acquired when the islanders abandoned their native Norn for Scots from the sixteenth century onwards, or a continuation of the dialects brought to Shetland by Scottish immigrants in the same period. More recently, Millar (2008) discussed the origins of Shetland Scots in a theory of new-dialect formation (Trudgill 2004), which allows for a combination of earlier explanations. In this article, I give a systematic analysis of the phonetics and phonology of Early Shetland Scots in comparison to Norn and mainland Scots dialects. The Shetland Scots data are largely consistent with theoretical expectations, lending further support to the new-dialect reading of the dialect's diachronic development.
Using tracer observations to reduce the uncertainty of ocean diapycnal mixing and climate–carbon cycle projections
Authors: Schmittner Andreas , Urban Nathan M. , Keller Klaus , Matthews Damon
Published: October 2009

What is the uncertainty of climate–carbon cycle projections in response to anthropogenic greenhouse gas emissions, and how can we reduce this uncertainty? We address this question by quantifying the ability of available ocean tracer observations to constrain the values of diapycnal diffusivity in the pelagic ocean (Kv), a key uncertain parameter representing sub‐grid‐scale diapycnal (vertical) mixing in physical circulation models. We show that model versions with weak mixing (i.e., low Kv) lead to higher projections of atmospheric CO2 and larger global warming than do models with vigorous mixing. Slower heat uptake and slower carbon uptake by the oceans contribute about equally to the accelerated warming in the low‐mixing models. A Bayesian data‐model fusion method is developed to quantify the likelihood of different structural and parametric model choices given an array of observed 20th century ocean tracer distributions. These spatially resolved observations provide strong limits on the upper value of Kv, whereas global metrics used in previous studies, such as the historical evolution of global average surface air temperature, global ocean heat uptake, or atmospheric CO2 concentration, provide only poor constraints. We compare different methods to quantify the probability of a particular diffusivity value given the observational constraints. One‐dimensional, globally horizontally averaged data result in sharper probability density functions compared with the full 3‐D fields. This perhaps unexpected result opens up an avenue to objectively determine the optimal degree of aggregation at which model predictions have skill, and at which observations are most helpful in constraining model parameters. Our best estimate for Kv in the pelagic pycnocline is around 0.05–0.2 cm2/s, in agreement with earlier independent estimates based on tracer dispersion experiments and turbulence microstructure measurements.
Morphological evolution of the Venice lagoon: Evidence from the past and trend for the future
Authors: Carniello Luca , Defina Andrea , D'Alpaos Luigi
Published: October 2009

During the last century, the Venice lagoon, Italy, has been experiencing a general degradation consisting of the deepening of tidal flats and the reduction of salt marsh areas. A conceptual model describing the long‐term evolution of such lagoons has recently been proposed. According to the model, the long‐term degradation consists of two steps: an initial salt marsh deterioration phase followed by a tidal flat erosion phase. In this work we test the long‐term evolution model through the analysis of four different bathymetries of the Venice lagoon during the last century (1901, 1932, 1970, and 2003). The result of the analysis confirms that the recent past morphological evolution of the Venice lagoon has actually followed the proposed model and highlights a slower erosive trend characterizing the northern part of the lagoon compared to the moderately rapid erosion affecting the central southern part. This result enables us to infer the likely future evolution of the Venice lagoon as long as the present forcing conditions are maintained.
Thermal evolution of the Sisters shear zone, southern New Zealand; Formation of the Great South Basin and onset of Pacific‐Antarctic spreading
Authors: Kula Joseph , Tulloch Andy J. , Spell Terry L. , Wells Michael L. , Zanetti Kathleen A.
Published: October 2009

The separation of Zealandia from West Antarctica was the final stage in the Cretaceous breakup of the Gondwana Pacific margin. Continental extension resulting in formation of the Great South Basin and thinning of the Campbell Plateau leading to development of the Pacific‐Antarctic spreading ridge was partially accommodated along the Sisters shear zone. This east‐northeast striking brittle‐ductile structure exposed along the southeast coast of Stewart Island, New Zealand, is a greenschist facies extensional shear zone that separates a hanging wall of chloritic, brecciated granites, and undeformed conglomerate from a footwall of mylonitic Carboniferous and Early Cretaceous granites. This complex structure exhibits bivergent kinematics and can be subdivided into a northern and southern segment. The 40Ar/39Ar thermochronology indicates that cooling of the shear zone footwall began at ∼94 Ma with accelerated cooling over the interval ∼89–82 Ma. Structural and thermochronological data indicate a spatial and temporal link between the Sisters shear zone, initial sedimentation within the offshore Great South Basin, extension of the Campbell Plateau, and initiation of the Pacific‐Antarctic spreading ridge.
Interseismic pore compaction suppresses earthquake occurrence and causes faster apparent fault loading
Authors: Mitsui Yuta , Hirahara Kazuro
Published: October 2009

Physical and chemical processes operating on faults during interseismic periods are important for earthquake generation. In this study, we focus on pore compaction within fault zones driven by chemical kinetic effects. One established model of compaction causes an increase of pore fluid pressure almost linearly with time, if fluid diffusion is neglected. We introduced it into a simple numerical model for earthquake cycles and found that this effect can drastically change the recurrence of earthquakes: (1) It gradually stabilizes the fault and eventually suppresses earthquake occurrence (2) It surprisingly causes faster “apparent” fault loading. Furthermore, we developed an expression for the “apparent” loading velocity and checked that it is consistent with the results of numerical calculations. We also extended the expression for the “apparent” loading velocity to include the effect of pore dilatancy. This “apparent” loading would not only appear in a simple elastic system with a single degree of freedom, but also in complicated systems that involve simulations of realistic earthquake cycles.
Influence of bin time and excitation intensity on fluorescence lifetime distribution and blinking statistics of single quantum dots
Authors: Lee Der-Hau , Yuan Chi-Tsu , Tachiya M. , Tang Jau
Published: October 2009

In this study of single CdSe/ZnS quantum dots in a polymethyl methacrylate (PMMA) matrix, we report narrowing of fluorescence lifetime distribution with increased bin time or excitation intensity mostly due to statistical variance of photon counts per bin and Auger relaxation. We also observed saturation for the excitation intensity dependence of the exponential bending rate for the blinking statistics for quantum dots in PMMA but not on glass.
Radiation stability of CsBr:Eu needle image plates
Authors: Batentschuk M. , Neudert S. , Weidner M. , Osvet A. , Struye L. , Tahon J.-P. , Leblans P.
Published: October 2009

Needle image plates (NIPs) based on CsBr:Eu are a good alternative to the BaFBr:Eu powder image plates due to their higher sensitivity and improved spatial resolution. The x-ray radiation stability of the NIPs produced by Agfa Gevaert was investigated and it was found that the radiation stability of the optimized NIPs is as high as that of the commercial CsI:Tl single crystals and much higher than reported in literature for the CsBr:Eu NIPs. The dependence of the sensitivity of the NIPs on the accumulated dose was determined for three different types of x-ray irradiation. It is shown that degradation of the sensitivity starts at about 10 Gy and it is the strongest for the most hard x-ray beam. If the energy absorbed by a NIP is taken into account, the degradation does not depend on the hardness of the applied x-ray beam. It is suggested that the main reason for the observed high radiation stability of the CsBr:Eu NIPs is the use of the oxygen-free Eu2+-containing precursor CsEuBr3 for the doping in the manufacturing process.
Practical efficiency limits in organic photovoltaic cells: Functional dependence of fill factor and external quantum efficiency
Authors: Servaites Jonathan D. , Ratner Mark A. , Marks Tobin J.
Published: October 2009

We evaluate practical power conversion efficiency limits (ηlim) in bulk-heterojunction organic photovoltaic (BHJ OPV) cells and how the field dependence of exciton dissociation affects cell efficiencies. We treat the fill factor limit as a function of the donor-acceptor lowest unoccupied molecular orbital offset energy (ELLO), calculating how this limit varies with decreasing ELLO. We also evaluate OPV external quantum efficiency as a function of wavelength from the optical transmittance and internal quantum efficiency limitations. For a given ELLO, we numerically optimize donor bandgap and ηlim and show that ηlim>10% should be possible for hypothetical OPV systems generating free charge carriers efficiently at ELLO∼0.3–0.4 eV. Current BHJ OPVs with low ELLO values appear to be limited to cell efficiencies of ∼5% largely as a consequence of incomplete exciton dissociation.
Intermolecular potential energy surface and second virial coefficients for the nonrigid water-CO dimer
Authors: Wheatley Richard J. , Harvey Allan H.
Published: October 2009

A seven-dimensional potential energy surface is calculated for the interaction of water and carbon monoxide using second-order Møller–Plesset theory, coupled-cluster theory, and extrapolated intermolecular perturbation theory. The effects of stretching the CO molecule and bending the water molecule are included. The minimum energy structure of the water-CO dimer changes from an H–C hydrogen bond to an H–O hydrogen bond when the CO bond length increases by less than 10 pm from its equilibrium value. Second virial coefficients for the water-CO interaction are calculated for a wide range of temperatures and compared with the limited experimental data. Allowing the CO bond length and water bond angle to vary has little effect on the second virial coefficients.
Field-structured composites for efficient, directed heat transfer
Authors: Martin James E. , Gulley G.
Published: October 2009

Thermally conductive composites are needed for a variety of applications, especially as thermal interface materials. Unfortunately, the addition of even highly conductive particles to a polymer raises its conductivity only slightly and incurs a commensurate increase in the viscosity of the prepolymer resin. Meaningful increases in the thermal conductivity of the final composite require a filled resin that has the rheology of a typical paste. In this paper, we report on the use of uniaxial, biaxial, and triaxial ac magnetic fields to organize thermally conductive magnetic particles into structures that conduct heat more efficiently. Experimental results are compared to an extension of the Maxwell–Eucken theory that takes into account spatial correlations between particles. Both theory and experiment show that the thermal conductivity of field-structured composites increases essentially linearly with particle loading, and that the enhancement is significantly greater than that of unstructured composites. The measured conductivity enhancements are found to be comparable to the enhancements in magnetic permeability of these composites and are far less than the enhancements in the electrical conductivity. These results indicate the value of field structuring in enhancing the performance of a thermal interface material and show that particle percolation is not a critical factor in achieving high performance.
Influence of mechanical stress on the correlation between grain boundaries and dipole relaxation in polycrystalline C60
Authors: Cui Guanglei , Gu Min , Tang Tong B.
Published: October 2009

Dielectric spectroscopy was performed on uniaxially compacted C60 pellets at selected frequencies from 1 kHz to 1 MHz as the temperature rose from 100 to 530 K. A new dielectric relaxation with activation energy of 2.45±0.05 eV was discerned, but which disappeared when the pellet was heated a second time. Dipoles relaxation accompanying orientational glass transition was observed at lower temperatures as asymmetrical loss peaks, showing departure from Debye behavior, but correlation among the oscillators decreased during the second heating cycle, and the activation energy was also reduced. We analyze the asymmetrical peaks with the help of Ngai's correlated-state model, and suggest that residual stresses in the pressed pellets enhance the correlation between grain boundary motion and the reorientational jumps of C60 molecules.
Exact ground state Monte Carlo method for Bosons without importance sampling
Authors: Rossi M. , Nava M. , Reatto L. , Galli D. E.
Published: October 2009

Generally “exact” quantum Monte Carlo computations for the ground state of many bosons make use of importance sampling. The importance sampling is based either on a guiding function or on an initial variational wave function. Here we investigate the need of importance sampling in the case of path integral ground state (PIGS) Monte Carlo. PIGS is based on a discrete imaginary time evolution of an initial wave function with a nonzero overlap with the ground state, which gives rise to a discrete path which is sampled via a Metropolis-like algorithm. In principle the exact ground state is reached in the limit of an infinite imaginary time evolution, but actual computations are based on finite time evolutions and the question is whether such computations give unbiased exact results. We have studied bulk liquid and solid H4e with PIGS by considering as initial wave function a constant, i.e., the ground state of an ideal Bose gas. This implies that the evolution toward the ground state is driven only by the imaginary time propagator, i.e., there is no importance sampling. For both phases we obtain results converging to those obtained by considering the best available variational wave function (the shadow wave function) as initial wave function. Moreover we obtain the same results even by considering wave functions with the wrong correlations, for instance, a wave function of a strongly localized Einstein crystal for the liquid phase. This convergence is true not only for diagonal properties such as the energy, the radial distribution function, and the static structure factor, but also for off-diagonal ones, such as the one-body density matrix. This robustness of PIGS can be traced back to the fact that the chosen initial wave function acts only at the beginning of the path without affecting the imaginary time propagator. From this analysis we conclude that zero temperature PIGS calculations can be as unbiased as those of finite temperature path integral Monte Carlo. On the other hand, a judicious choice of the initial wave function greatly improves the rate of convergence to the exact results.
Ferromagnetic Sc-doped AlN sixfold-symmetrical hierarchical nanostructures
Authors: Lei W. W. , Liu D. , Zhu P. W. , Chen X. H. , Zhao Q. , Wen G. H. , Cui Q. L. , Zou G. T.
Published: October 2009

Sc-doped AlN (AlN:Sc) sixfold-symmetrical hierarchical nanostructures were grown by direct current (dc) arc discharge plasma method using the direct reaction of Al and Sc metals with N2 gas. Energy-dispersive x-ray spectroscopy, x-ray diffractometry, and Raman spectra analysis clearly showed that Sc was doped in the AlN hierarchical nanostructures. The magnetization curves indicate the existence of room-temperature ferromagnetic behavior. The saturation magnetization and the coercive fields (Hc) of the AlN:Sc nanostructures are about 0.04 emu g−1 and 200 Oe, respectively. The results reveal that Sc is a potential nonmagnetic dopant for preparing diluted magnetic semiconductor nanomaterials.
Suspended metal wire array as a thermoacoustic sound source
Authors: Niskanen A. O. , Hassel J. , Tikander M. , Maijala P. , Grönberg L. , Helistö P.
Published: October 2009

We demonstrate that a suspended metal wire array can be used to produce high-pressure sound waves over a wide spectrum using the thermoacoustic effect. We fabricated air-bridge arrays containing up to 2×105 wires covering an area of a few square centimeters. The supporting silicon wafer was isotropically plasma etched to release the wires thereby avoiding heat contact with the substrate. Sound pressure levels reaching 110 dB at a distance of 8 cm were demonstrated near 40 kHz in free field. The devices are also able to reproduce music and speech. They have potential for applications especially in the ultrasound range.
Growth and properties of chemical solution deposited BiInO3–PbTiO3 films
Authors: Ko S. W. , Yeo H. G. , Trolier-McKinstry S.
Published: October 2009

The dielectric, ferroelectric, and piezoelectric properties of chemical solution deposited xBiInO3–(1−x)PbTiO3 (0.10≤x≤0.35) thin films on platinized silicon substrates were investigated. Using a PbTiO3 seed layer, phase pure xBiInO3–(1−x)PbTiO3 (0.10≤x≤0.35) thin films were prepared. For a 470 nm thick 0.15BiInO3–0.85PbTiO3 film, the room temperature permittivity was 650, while the dielectric loss tangent was below 2%. The coercive field and remanent polarization were 73 kV/cm and 22 μC/cm2, respectively. The ferroelectric transition temperatures of the xBiInO3–(1−x)PbTiO3 (x=0.10–0.20) films were all in excess of 550 °C. For x=0.15, the e31,f piezoelectric coefficient was −2.7 C/m2.
The Question of Scale in Housing-Led Regeneration: Tied to the Neighbourhood?
Authors: Pinnegar Simon
Published: October 2009

Despite recognition of the fluid, interconnected nature of urban drivers and outcomes operating across a variety of spatial scales, the use of area-based initiatives in urban regeneration and renewal policy continues to fix space in order to identify scope, determine legitimacy, and clarify accountability. Even if multiple scales are acknowledged in policy discourse and strategy, actual boundaries defining a policy's geography of interest have typically focused on the neighbourhood. The emergence of citywide or subregional regeneration initiatives, such as England's Housing Market Renewal pathfinder programme and Philadelphia's Neighborhood Transformation Initiative, have been accompanied by different considerations as to how space is negotiated and enrolled both in strategic and in delivery terms. Using these ‘market shaping’ initiatives as a basis for discussion, I seek to add to debates regarding the tensions tied up in fixing space from the practical perspective of programme implementation. While a partial defence of boundary setting is offered, the influence and impact of scale arising from the delimitation of space are seen as crucial factors in determining how complex initiatives sustain their rationale and deliver in practice. Exploring the challenges created by the disjuncture between the spaces of strategic thinking and the impact of those policies as experienced on the ground, the paper concludes by offering some perspectives as to why the neighbourhood retains a pervasive hold within regeneration policy as the point of mediation between the local and global.
Effects of perennial species on the demography of annual grass weeds in pastures subject to seasonal drought and grazing
Authors: Tozer K. N. , Chapman D. F. , Cousens R. D. , Quigley P. E. , Dowling P. M. , Kearney G. A. , Cameron C. A.
Published: October 2009

A field experiment was established in a southern Australian temperate pasture to investigate the effects of identity and proximity of perennial grasses on the demography of the annual grasses Vulpia spp. (V. myuros, V. bromoides) and Hordeum leporinum (barley grass). Annual grasses were grown either alone or in mixtures, at different distances from rows of Dactylis glomerata (cocksfoot) and Phalaris aquatica (phalaris). Dactylis had a greater suppressive effect than Phalaris on Vulpia and Hordeum. Biomass, tiller production, and panicle production of annual grasses increased linearly with increasing distance from the perennial row. Tiller and panicle production were greater for Vulpia than Hordeum. The estimated rate of population growth (λ) for annual grasses was greater in Phalaris than in Dactylis and in Vulpia than in Hordeum, and increased with sowing distance from perennial grass rows. It was estimated that λ, when seeds were sown directly adjacent to a row of perennial grasses, was 1 and 0.4 for Vulpia and Hordeum, respectively, within Dactylis stands, and 7 and 3, respectively, within Phalaris stands. However, 15 cm from the row, λ reached 50 and 39 for Vulpia and Hordeum, respectively, within Phalaris stands, and 39 and 16, respectively, within Dactylis stands. In grazed, dryland pastures, perennial competition alone is therefore unlikely to prevent population growth of annual grasses, especially in systems heavily disturbed by grazing or drought. However, Dactylis showed more promise than Phalaris in limiting the abundance of these weeds.
Re-inventing model-based decision support with Australian dryland farmers. 3. Relevance of APSIM to commercial crops
Authors: Carberry P. S. , Hochman Z. , Hunt J. R. , Dalgliesh N. P. , McCown R. L. , Whish J. P. M. , Robertson M. J. , Foale M. A. , Poulton P. L. , van Rees H.
Published: October 2009

Crop simulation models relevant to real-world agriculture have been a rationale for model development over many years. However, as crop models are generally developed and tested against experimental data and with large systematic gaps often reported between experimental and farmer yields, the relevance of simulated yields to the commercial yields of field crops may be questioned. This is the third paper in a series which describes a substantial effort to deliver model-based decision support to Australian farmers. First, the performance of the cropping systems simulator, APSIM, in simulating commercial crop yields is reported across a range of field crops and agricultural regions. Second, how APSIM is used in gaining farmer credibility for their planning and decision making is described using actual case studies.
Information was collated on APSIM performance in simulating the yields of over 700 commercial crops of barley, canola, chickpea, cotton, maize, mungbean, sorghum, sugarcane, and wheat monitored over the period 1992 to 2007 in all cropping regions of Australia. This evidence indicated that APSIM can predict the performance of commercial crops at a level close to that reported for its performance against experimental yields. Importantly, an essential requirement for simulating commercial yields across the Australian dryland cropping regions is to accurately describe the resources available to the crop being simulated, particularly soil water and nitrogen.
Five case studies of using APSIM with farmers are described in order to demonstrate how model credibility was gained in the context of each circumstance. The proposed process for creating mutual understanding and credibility involved dealing with immediate questions of the involved farmers, contextualising the simulations to the specific situation in question, providing simulation outputs in an iterative process, and together reviewing the ensuing seasonal results against provided simulations.
This paper is distinct from many other reports testing the performance and utility of cropping systems models. Here, the measured yields are from commercial crops not experimental plots and the described applications were from real-life situations identified by farmers. A key conclusion, from 17 years of effort, is the proven ability of APSIM to simulate yields from commercial crops provided soil properties are well characterised. Thus, the ambition of models being relevant to real-world agriculture is indeed attainable, at least in situations where biotic stresses are manageable.
Difference in yield and persistence among perennial forages used by the dairy industry under optimum and deficit irrigation
Authors: Neal J. S. , Fulkerson W. J. , Lawrie R. , Barchia I. M.
Published: October 2009

Perennial ryegrass (Lolium perenne L.) is the dominant forage grazed by dairy cows in Australia; however, poor persistence has led to an increasing interest in alternative forages. This study was conducted to identify more productive and/or persistent perennial forage species than perennial ryegrass. We evaluated 15 perennial forages under optimum irrigation (I1) and 2 nominated deficit irrigation (I2, 66% of irrigation water applied to I1; I3, 33% of irrigation water applied to I1) regimes, over 3 years at Camden, NSW (34°3′S, 150°39′E), on a brown Dermosol in a warm temperate climate. The forages were: perennial ryegrass, cocksfoot (Dactylis glomerata L.), phalaris (Phalaris aquatica L.), prairie grass (Bromus catharticus M. Vahl), tall fescue (Schedonorus phoenix (Scop.) Holub), kikuyu (Pennisetum clandestinum Hochst. ex. chiov.), paspalum (Paspalum dilatatum Poir.), birdsfoot trefoil (Lotus corniculatus L.), lucerne (Medicago sativa L.), red clover (Trifolium pratense L.), strawberry clover (Trifolium fragiferum L.), sulla (Hedysarum coronarium L.), white clover (Trifolium repens L.), chicory (Cichorium intybus L.), and plantain (Plantago lanceolata L.).
Under non-limiting conditions of water and fertility, tall fescue, kikuyu, and prairie grass had the highest mean annual yield over the 3 years of this experiment (24.8–25.5 t dry matter (DM)/ha), which was significantly greater (P < 0.05) than perennial ryegrass (21.1 t DM/ha). Kikuyu was significantly higher than all forages under the extreme I3 deficit irrigation treatment, with mean annual yields of 17.0 t DM/ha. In contrast, the mean yield of white clover was significantly lower (P < 0.05) than of any other forage at only 5.0 t DM/ha, a 70% decline in yield compared with I1. Lucerne was the most tolerant species to deficit irrigation, with a mean annual yield decline (P < 0.05) between the I1 and I3 treatment of only 22%. This study has shown that there are large differences in the relative yield potential of forages and, importantly, indicates the possibility of increasing yield of perennial forages by at least 2-fold on commercial farms, by improving water, and fertiliser management. However, while yield is an important criterion for choosing dairy forages, it is only one factor in a complex system, and choice of forages must be considered on a whole-farm basis and include water-use efficiency, nutritive value, costs of production, and risk.
Keratins and protein synthesis: the plot thickens
Authors: Kellner Juliane C. , Coulombe Pierre A.
Published: October 2009

In addition to protecting epithelial cells from mechanical stress, keratins regulate cytoarchitecture, cell growth, proliferation, apoptosis, and organelle transport. In this issue, Vijayaraj et al. (2009. J. Cell Biol. doi:10.1083/jcb.200906094) expand our understanding of how keratin proteins participate in the regulation of protein synthesis through their analysis of mice lacking the entire type II keratin gene cluster.
Logically rectangular finite volume methods with adaptive refinement on the sphere
Authors: Berger Marsha J. , Calhoun Donna A. , Helzel Christiane , LeVeque Randall J.
Published: October 2009

The logically rectangular finite volume grids for two-dimensional partial differential equations on a sphere and for three-dimensional problems in a spherical shell introduced recently have nearly uniform cell size, avoiding severe Courant number restrictions. We present recent results with adaptive mesh refinement using the G
eo
C
law
software and demonstrate well-balanced methods that exactly maintain equilibrium solutions, such as shallow water equations for an ocean at rest over arbitrary bathymetry.
Kimura’s disease mimicking an earlobe keloid
Authors: Yeh S. W. , Lee W. R. , Hu C. H. , Tsai H. H.
Published: October 2009

Kimura’s disease (KD) is a rare chronic inflammatory disorder of unknown aetiology. It usually presents as soft-tissue masses predominantly in the head or neck region. We report a case of an asymptomatic tumour on the left earlobe mimicking a keloid. The tumour was histopathologically diagnosed as KD. This case suggests the importance of conducting skin biopsies of keloidal lesions on head and neck regions, particularly in patients who have peripheral eosinophilia and increased IgE levels.
Testing the influence of local forest canopy clearing on phenotypic variation in Trinidadian guppies
Authors: Schwartz Amy K. , Hendry Andrew P.
Published: October 2009

1. Factors contributing to the maintenance of phenotypic variation in nature are often difficult to determine. Secondary sexual traits might be particularly interesting in this regard due to the interaction they experience between multiple selective agents. One way to examine such effects is to monitor populations following environmental change. Human‐caused changes can be particularly useful here because they often involve an abrupt and extreme alteration of specific habitat features. This alteration can then precipitate phenotypic plasticity, changes in adaptive landscapes, and modified evolutionary trajectories. The consequences of habitat manipulations on local populations can therefore improve our understanding of phenotypic variation in complex ecological systems.

2. We took advantage of a human‐caused environmental disturbance to examine factors influencing phenotypic variation in Trinidadian guppies (Poecilia reticulata). Differences in canopy cover along the stream have been hypothesized to explain some of this variation, but this has been hard to test directly. We here attempt a direct test of this hypothesis by monitoring changes in guppy size and colour following a dramatic decrease in canopy cover due to tree removal for agricultural activity.

3. Although male and female body size increased following canopy clearing, little change was observed in the overall amount of melanin‐based colours, carotenoid‐based colours, and structural colours on males. We further compared phenotypes before and after canopy clearing at the disturbed site to those from two nearby reference sites that are at extreme ends of canopy cover. Overall, variation in colour was attributed to differences among sites, irrespective of canopy differences. We also found considerable temporal variation in some colour elements at a given site.

4. Our results suggest that differences in light availability do not cause rapid and dramatic changes in guppy colour. The substantial unexplained variation must therefore be due to factors other than canopy (measured here) and predation regime (all sites were ‘low‐predation’). Because of the multiple and complex interactions involved in the expression and maintenance of sexually selected traits, our study emphasizes the need for a better understanding of both the genetic and environmental sources of co‐variation between sexual ornaments and preferences.