bluuebunny/crossref_metadata_2025 huggingface dataset:
A common visual metric for approximate number and density
Authors: Dakin Steven C. , Tibber Marc S. , Greenwood John A. , Kingdom Frederick A. A. , Morgan Michael J.
Published: November 2011

There is considerable interest in how humans estimate the number of objects in a scene in the context of an extensive literature on how we estimate the density (i.e., spacing) of objects. Here, we show that our sense of number and our sense of density are intertwined. Presented with two patches, observers found it more difficult to spot differences in either density or numerosity when those patches were mismatched in overall size, and their errors were consistent with larger patches appearing both denser and more numerous. We propose that density is estimated using the relative response of mechanisms tuned to low and high spatial frequencies (SFs), because energy at high SFs is largely determined by the number of objects, whereas low SF energy depends more on the area occupied by elements. This measure is biased by overall stimulus size in the same way as human observers, and by estimating number using the same measure scaled by relative stimulus size, we can explain all of our results. This model is a simple, biologically plausible common metric for perceptual number and density.
Crumbs regulates rhodopsin transport by interacting with and stabilizing myosin V
Authors: Pocha Shirin Meher , Shevchenko Anna , Knust Elisabeth
Published: November 2011

The evolutionarily conserved Crumbs (Crb) complex is crucial for photoreceptor morphogenesis and homeostasis. Loss of Crb results in light-dependent retinal degeneration, which is prevented by feeding mutant flies carotenoid-deficient medium. This suggests a defect in rhodopsin 1 (Rh1) processing, transport, and/or signaling, causing degeneration; however, the molecular mechanism of this remained elusive. In this paper, we show that myosin V (MyoV) coimmunoprecipitated with the Crb complex and that loss of crb led to severe reduction in MyoV levels, which could be rescued by proteasomal inhibition. Loss of MyoV in crb mutant photoreceptors was accompanied by defective transport of the MyoV cargo Rh1 to the light-sensing organelle, the rhabdomere. This resulted in an age-dependent accumulation of Rh1 in the photoreceptor cell (PRC) body, a well-documented trigger of degeneration. We conclude that Crb protects against degeneration by interacting with and stabilizing MyoV, thereby ensuring correct Rh1 trafficking. Our data provide, for the first time, a molecular mechanism for the light-dependent degeneration of PRCs observed in crb mutant retinas.
Absence of magnetism in Cr-doped In2O3: a case study of phase separation versus phase formation
Authors: Gaur Anand P S , Sahoo Satyaprakash , Katiyar R K , Rinaldi C , Scott J F , Katiyar R S
Published: November 2011

Bulk ceramic Cr-doped In2O3 have been prepared using a solid-state reaction method at two different annealing temperatures. Room-temperature ferromagnetic behaviour is observed for all the compositions prepared at relatively low temperature. But from the Raman study the ferromagnetic oxide phase of CrO2 was identified. On the other hand, samples prepared at relatively high temperature show no detectable secondary phases as confirmed by x-ray diffraction and Raman study, but also no ferromagnetism. With increase in Cr content the paramagnetism state is merely enhanced. This is a strong indication that reports of ferromagnetism in Cr : In2O3 are due to a second phase, probably CrO2.
Evanescent coupling in buried planar waveguide arrays written by a femtosecond laser in neodymium-doped yttrium lithium fluoride (Nd : YLiF4)
Authors: Liu Xiaoyu , Qu Shiliang , Tan Yang , Chen Feng
Published: November 2011

We report on the fabrication of buried planar waveguide arrays in neodymium-doped yttrium lithium fluoride (Nd : YLiF4) by femtosecond laser writing. With optimized fabrication parameters, the individual waveguide modes are coupled to each other through the evanescent tails of adjacent guided fields, while the coupling constant is calculated to be 1.18 cm−1 at 633 nm based on coupled-mode theory, which shows good agreement with the experiment results. Micro-luminescence spectra reveal that the Nd3+ fluorescence properties are not significantly affected by the waveguide formation processing, which indicates a fairly good potential for further laser actions in a compact device.
The study of dislocation dynamics in thermally aged Fe–1%Cu–C alloys by internal friction measurements
Authors: Minov B , Dupré L , Konstantinović M J
Published: November 2011

The effect of copper precipitation and the role of carbon in the dislocation dynamics of thermally aged Fe–1%Cu–C alloys are studied by measuring the internal friction coefficient of non-deformed and cold-worked samples in the temperature range from 100 to 600 K. In non-deformed samples we observe a complex behaviour of the Snoek-relaxation peak intensity, which indicates the existence of carbon redistribution governed by the copper precipitation. In cold-worked samples, the behaviour of dislocation-related relaxation processes is explained through an increase in hardening due to copper precipitation at early precipitation stages, and through the carbon redistribution which seems to play a major role in the alloy softening at later precipitation stages.
Quantitative 3D refractive index decrement reconstruction using single-distance phase-contrast tomography data
Authors: Chen R C , Rigon L , Longo R
Published: November 2011

X-ray propagation-based phase-contrast imaging is an attractive phase-sensitive imaging technique that has found applications in many research fields. Here, we report the investigations of a method which can quantitatively reconstruct in 3D the refractive index decrement of a quasi-homogeneous object using single-distance phase-contrast tomography data. The method extends the Born-type approximation phase-retrieval algorithm, which is based on the phase-attenuation duality (ε = δ/β, with constant ε) and suitable for homogeneous objects, to tomography and we study its application to quasi-homogeneous objects. The noise performance and the phase-attenuation duality influences of the method are also investigated. In simulation, the method allows us to quantitatively reconstruct the 3D refractive index decrement for quasi-homogeneous and weakly absorbing samples and it performs well in the practical noise situation. Furthermore, it shows a substantial contrast increase and successfully distinguishes different materials in a quasi-homogeneous and weakly absorbing sample from experimental data, even with inappropriate ε value.
Identification and Characterization of a Novel Gene, hshB, in Xanthomonas oryzae pv. oryzicola Co-Regulated by Quorum Sensing and clp
Authors: Zhao Yancun , Qian Guoliang , Fan Jiaqin , Yin Fangqun , Zhou Yijin , Liu Chunhui , Shen Qin , Hu Baishi , Liu Fengquan
Published: November 2011

Virulence factors of Xanthomonas oryzae pv. oryzicola, the causal agent of bacterial leaf streak in rice, are regulated by a diffusible signal factor (DSF)-dependent quorum-sensing (QS) system. In this study, a novel pathogenicity-related gene, Xoryp_010100018570 (named hshB), of X. oryzae pv. oryzicola was characterized. hshB encodes a hydrolase with a putative signal peptide, which is a homolog of imidazolonepropionase. Bioinformatic analysis showed that hshB is relatively conserved in the genus Xanthomonas but the homologous gene of hshB was not found in X. oryzae pv. oryzae. Reverse-transcription polymerase chain reaction (PCR) analysis showed that hshB and its upstream gene, Xoryp_010100018565 (named hshA), are co-transcribed in X. oryzae pv. oryzicola. Subsequent experimental results indicated that mutation of hshB remarkably impaired the virulence, extracellular protease activity, extracellular polysaccharide production, growth in minimal medium, and resistance to oxidative stress and bismerthiazol of X. oryzae pv. oryzicola. Mutation of clp, encoding a global regulator, resulted in similar phenotypes. Real-time PCR assays showed that hshB transcription is positively regulated by clp and DSF, and induced by poor nutrition. Our study not only found a novel gene hshB regulated by DSF-dependent QS system and clp but also showed that hshB was required for virulence of X. oryzae pv. oryzicola.
Time-Dependent Infectivity and Flexible Latent and Infectious Periods in Compartmental Models of Plant Disease
Authors: Cunniffe N. J. , Stutt R. O. J. H. , van den Bosch F. , Gilligan C. A.
Published: November 2011

Compartmental models have become the dominant theoretical paradigm in mechanistic modeling of plant disease and offer well-known advantages in terms of analytic tractability, ease of simulation, and extensibility. However, underlying assumptions of constant rates of infection and of exponentially distributed latent and infectious periods are difficult to justify. Although alternative approaches, including van der Plank's seminal discrete time model and models based on the integro-differential formulation of Kermack and McKendrick's model, have been suggested for plant disease and relax these unrealistic assumptions, they are challenging to implement and to analyze. Here, we propose an extension to the susceptible, exposed, infected, and removed (SEIR) compartmental model, splitting the latent and infection compartments and thereby allowing time-varying infection rates and more realistic distributions of latent and infectious periods to be represented. Although the model is, in fact, more general, we specifically target plant disease by demonstrating how it can represent both the van der Plank model and the most commonly used variant of the Kermack and McKendrick (K & M) model (in which the infectivity response is delay Gamma distributed). We show how our reformulation retains the numeric and analytic tractability of SEIR models, and how it can be used to replicate earlier analyses of the van der Plank and K & M models. Our reformulation has the advantage of using elementary mathematical techniques, making implementation easier for the nonspecialist. We show a practical implication of these results for disease control. By taking advantage of the easy extensibility characteristic of compartmental models, we also investigate the effects of including additional biological realism. As an example, we show how the more realistic infection responses we consider interact with host demography and lead to divergent invasion thresholds when compared with the “standard” SEIR model. An ever-increasing number of analyses purportedly extract more biologically realistic invasion thresholds by adding additional biological detail to the SEIR model framework; we contend that our results demonstrate that extending a model that has such a simplistic representation of the infection dynamics may not, in fact, lead to more accurate results. Therefore, we suggest that modelers should carefully consider the underlying assumptions of the simplest compartmental models in their future work.
Association between the Apolipoprotein E4 and Postoperative Cognitive Dysfunction in Elderly Patients Undergoing Intravenous Anesthesia and Inhalation Anesthesia
Authors: Cai Yingmin , Hu Haitao , Liu Pengbin , Feng Gaifeng , Dong Weijiang , Yu Bing , Zhu Yulin , Song Jinxin , Zhao Minggang
Published: November 2011

Background

Intravenous and inhalation anesthesia are commonly used in the clinical setting. Recovery of cognitive function in elderly patients after surgery has received increased attention. In this study, the authors compared recovery of cognitive function in patients after different anesthesia techniques, and investigated which technique is safer. The authors also explored association between apolipoprotein E4 and postoperative cognitive dysfunction in patients undergoing general anesthesia.

Methods

A total of 2,000 patients were equally and randomly divided into intravenous and inhalation anesthesia groups. Total intravenous and inhalation anesthesia were used. Within 10 days after surgery, cognitive function was assessed daily using the Mini-Mental State Examination (MMSE). Restriction fragment length polymorphism of apolipoprotein E gene was analyzed. The primary outcome was MMSE score, frequency distribution of apolipoprotein E alleles and genotypes. P < 0.01 was used as statistically significant.

Results

MMSE score in inhalation preoperative baseline group significantly decreased at day 3 after surgery compared with the preoperational and intravenous anesthesia group. The proportion of patients scoring less than 25 points was significantly greater in the inhalation anesthesia group than in the intravenous anesthesia group at 3 days after surgery. In the inhalation anesthesia group, the decrease in MMSE score was closely related with apolipoprotein E ε4 allele. In the intravenous anesthesia group, the decrease in MMSE score was not correlated with apolipoprotein E ε4 allele.

Conclusions

There was a strong association between the apolipoprotein E ε4 and postoperative cognitive dysfunction in elderly patients undergoing inhalation anesthetics.
Phenotypic variation and associated predation risk of juvenile common carpCyprinus carpio
Authors: Weber M. J. , Rounds K. D. , Brown M. L.
Published: November 2011

Juvenile common carpCyprinus carpiowere collected from 10 lakes with variable predator abundance over 4 months to evaluate if morphological defences increased with increasing predation risk.Cyprinus carpiodorsal and pectoral spines were longer and body depth was deeper when predators were more abundant, with differences becoming more pronounced from July to October. To determine if morphological plasticity successfully reduced predation risk, prey selection of largemouth bassMicropterus salmoidesforaging on deep‐ and shallow‐bodiedC. carpiowas evaluated in open and vegetated environments. Predators typically selected deep‐ over shallow‐bodied phenotypes in open habitats and neutrally selected both phenotypes in vegetated habitats. When exposed to predators, shallow‐bodiedC. carpiophenotypes shoaled in open habitat, whereas deep‐bodied phenotypes occupied vegetation. Although deep‐bodied phenotypes required additional handling time, shallow‐bodied phenotypes were more difficult to capture. These results suggest that juvenileC. carpiogradually develop deeper bodies and larger spines as predation risk increases. Morphological defences made it more difficult for predators to consume these prey but resulted in higher vulnerability to predation in some instances.
C‐Type natriuretic peptide forms in adult hyperthyroidism: correlation with thyroid hormones and markers of bone turnover
Authors: Schouten Belinda J. , Prickett Timothy C. , Hunt Penelope J. , Richards A. Mark , Geffner Mitchell E. , Olney Robert C. , Espiner Eric A.
Published: November 2011

Context  Plasma C‐type natriuretic peptide (CNP) forms correlate with linear growth velocity in juveniles. In hyperthyroid children, plasma CNP products fall in parallel with height velocity and thyroid hormones (TH) as euthyroidism is restored. The effect of TH on CNP forms after completion of endochondral growth is unknown.

Objective  To determine the effect of restoring euthyroidism on plasma CNP forms and bone turnover markers (BTMs) in hyperthyroid adults.

Design and setting  We performed a prospective observational study in 20 adults (19 women) with acquired hyperthyroidism before and during carbimazole treatment.

Intervention and main outcomes  Blood levels of CNP, amino‐terminal propeptide of CNP (NTproCNP), TH and BTMs – bone‐specific alkaline phosphatase, osteocalcin, procollagen type 1 amino‐terminal propeptide and type 1 collagen C‐telopeptide (CTx) – were measured before and during the first 6 months of carbimazole treatment and correlations determined.

Results  Both CNP and NTproCNP were significantly correlated with TH at baseline. As in children, decreases in CNP forms were closely associated with fall in TH. Significant associations were found between CNP forms and CTx.

Conclusions  CNP production from tissues other than endochondral cartilage is responsive to TH. Strong temporal links with markers of bone resorption suggest that CNP may also participate in bone remodelling in the adult skeleton.
FGF23 contributes to insulin sensitivity in obese adolescents – preliminary results
Authors: Wojcik Malgorzata , Dolezal‐Oltarzewska Katarzyna , Janus Dominika , Drozdz Dorota , Sztefko Krystyna , Starzyk Jerzy B.
Published: November 2011

Fibroblast growth factor‐23 (FGF23) is a hormonal regulator of circulating phosphate and vitamin D levels. Recent investigations revealed that besides a key role in the pathogenesis of calcium–phosphorus disorders, in some patients FGF23 may be an indicator of cardiovascular complications. As a ‘hormone‐like’ factor, it may also be involved in some metabolic processes, especially in the metabolism of glucose and fat. Its potential contribution to metabolic syndrome (MS) development has not been confirmed yet.

Objective  The study was to examine the possible correlations between FGF23 serum levels and body composition, blood pressure and selected parameters of glucose, insulin and fat metabolism in adolescents with simple obesity.

Patients and design  In 68 (35 female) adolescents (mean age 13·9 years) with simple obesity [mean BMI SDS 4·9 (95% CI 4·4–5·4)], the levels of FGF23, total cholesterol, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol and triglycerides were measured. Standard oral glucose tolerance tests were performed with the assessment of fasting and after 120′ postload glucose and insulin levels; the insulin resistance index HOMA‐IR was calculated.

Results  Regardless of gender, there was a significant inverse correlation between FGF23 and fasting insulin level (r = −0·3), as well as HOMA‐IR (r = −0·29). Multiple regression model showed the independent association between FGF23 and HOMA‐IR.

Conclusion  FGF23 seems to be a novel factor contributing to insulin sensitivity. Further investigations are needed to define its role in the development of MS.
Limited effects of dominant ants on assemblage species richness in three Amazon forests
Authors: BACCARO FABRICIO BEGGIATO , DE SOUZA JORGE LUIZ P. , FRANKLIN ELIZABETH , LEMES LANDEIRO VICTOR , MAGNUSSON WILLIAM E.
Published: November 2011

1. Ants are highly interactive organisms and dominant species are considered to be able to control the species richness of other ants via competitive exclusion. However, depending on the scale studied, inter‐specific competition may or may not structure biological assemblages. To date, ant dominance–richness relationships have only been studied in small sample units, where a few dominant colonies could plausibly control most of the sample unit.

2. We conducted a comprehensive survey of terrestrial ant assemblages using bait, pitfall, and litter‐sorting methods in three sites in Brazilian Amazonia. Using a spatially structured rarefaction approach, based on sampling units with linear dimensions ranging from 25 to 250 m, the mesoscale patterns of ant dominance–richness relationships (sampling units covering hundreds of meters separated by kilometers) were investigated.

3. Interference–competition models (parabolic or negative linear relationships between species richness and the abundance of dominant ants) tended to be more frequent in smaller sample units or in assemblages sampled with interactive methods, such as baits. Using more inclusive sampling methods, the relationship was generally asymptotic rather than parabolic, with no reduction in species diversity because of the presence of dominants. Random co‐occurrence patterns of species within sites support the interpretation of a limited role for present‐day competition in structuring these assemblages.

4. Competition from dominant species may reduce species richness in small areas, especially when artificial baits are used, but appears to be less important than environmental constraints in determining ant species richness across scales of hectares and greater in these Amazon forests.
Assessing risks of pine wood nematode Bursaphelenchus xylophilus transfer between wood packaging by simulating assembled pallets in service
Authors: Sousa E. , Naves P. , Bonifácio L. , Henriques J. , Inácio M. L. , Evans H.
Published: November 2011

The risks of Bursaphelenchus xylophilus (pine wood nematode) transfer in relation to wood material were assessed. Combinations of infested and non‐infested adjacent boards, long‐blocks and blocks of Pinus pinaster, simulating assembled pallets, were assessed. For the recipient wood, pieces with natural moisture content (MC), heat‐treatment (56°C for 30 min in the core) and kiln‐drying to <20% MC were tested, along with in‐service boards from pallets. Donor and recipient wood materials were kept in direct contact at 25°C or 10°C, with nine replicates per treatment. Bursaphelenchus xylophilus was found to transfer rapidly at 25°C when the wood had an MC above fibre‐saturation point (>30%). Nematode reproduction was rapid and sustained, gradually declining to zero at 40 weeks. Bursaphelenchus xylophilus did not transfer to kiln‐dried or to in‐service wood with an MC below fibre‐saturation point, or to wood at 10°C. The key factors determining nematode transfer were the ambient temperature, the nematode load of the donor wood and the MC of the recipient wood, with a ‘barrier’ of 20% MC below which it becomes unsuitable for nematode transfer. This finding indicates that there is a limited risk of spread of B. xylophilus in treated and untreated solid wood packaging materials.
Another role for the VW molecule
Authors: ALEDORT L. M.
Published: November 2011

Summary.  My comments on the implication of the vW molecule in down‐regulating the immunogenicity of factor VIII.
Detection of potentially pathogenic Aeromonas isolates from ready‐to‐eat seafood products by PCR analysis
Authors: Pinto Angela Di , Terio Valentina , Pinto Pietro Di , Tantillo Giuseppina
Published: November 2011

This study provides data on the prevalence of potentially pathogenic Aeromonas spp. in ready‐to‐eat (RTE) seafood products by evaluating the occurrence of Aeromonas spp. and the presence of virulence‐associated genes. Aeromonas spp. was detected in 57/81 (70.3%) RTE seafood samples. Specifically, Aeromonas spp. was highlighted in 19/21 (90.5%) sushi, in 18/21 (85.7%) sea salad, 11/12 (91.7%) surimi and 9/12 (75%) peeled shrimp samples. Aeromonas spp. was not observed in marinated anchovies and octopus salad samples. Then, PCRs aimed at the hlyA, aerA, alt and ast genes, encoding, respectively, haemolysin A, aerolysin, aeromonas labile temperature cytotonic enterotoxin and aeromonas stable temperature cytotonic enterotoxin, demonstrated a widespread distribution of these genes among Aeromonas isolates. The results underline the need to implement an adequate control plan performing an intensive and continuous monitoring to guarantee the human health.
Purification, characterisation and application of α‐l‐rhamnosidase from Penicillium citrinum MTCC‐8897
Authors: Yadav Sarita , Yadav Vinita , Yadav Sudha , Yadav Kapil D.S.
Published: November 2011

An α‐l‐rhamnosidase secreted by Penicillium citrinum MTCC‐8897 has been purified to homogeneity from the culture filtrate of the fungal strain using ammonium sulphate precipitation and cation‐exchange chromatography on carboxymethyl cellulose. The sodium dodecyl sulphate/polyacrylamide gel electrophoresis analysis of the purified enzyme gave a single protein band corresponding to the molecular mass 51.0 kDa. The native polyacrylamide gel electrophoresis also gave a single protein band confirming the enzyme purity. The Km and Vmax values of the enzyme for p‐nitrophenyl α‐l‐rhamnopyranoside were 0.36 mm and 22.54 μmole min−1 mg−1, respectively, and kcat value was 17.1 s−1 giving kcat/Km value of 4.75 × 104 m−1 s−1. The pH and temperature optima of the enzyme were 7.0 and 60 °C, respectively. The purified enzyme liberated l‐rhamnose from naringin, rutin, hesperidin and wine, indicating that it has biotechnological application potential for the preparation of l‐rhamnose and other pharmaceutically important compounds from natural glycosides containing terminal α‐l‐rhamnose and also in the enhancement of wine aroma.
Characterisation of natural honey proteins: implications for the floral and geographical origin of honey
Authors: Mohammed Seif Eldin A. , Azim M. Kamran
Published: November 2011

Characterisation of honey proteins has been considered advantageous for differentiating floral and geographical origin of honey. We analysed protein profiles of multi‐ and mono‐floral honey samples from different regions and harvest dates. The molecular masses of chromatographic peaks were in the range of 10–>200 kDa. Owing to comparable molecular masses, interesting correlation between profiles of honey proteins reported earlier and observed in this study could be established. Chromatograms of honey proteins revealed three novel peaks of molecular masses ∼220, 129 and 26 kDa. Statistical analysis of peak areas showed that the 84‐kDa peak was different among all honey samples and the 220‐kDa peak was important for differentiation between multi‐ and mono‐floral honey samples. Chromatograms of several‐year‐old honey samples were different from fresh samples because of depletion of high molecular mass peaks that indicated in situ proteolysis. The results supported the notion of applying gel filtration as cost‐effective and robust technique for honey protein characterisation.
Impacts of climate, host and landscape factors on Culicoides species in Scotland
Authors: PURSE B. V. , FALCONER D. , SULLIVAN M. J. , CARPENTER S. , MELLOR P. S. , PIERTNEY S. B. , MORDUE (LUNTZ) A. J. , ALBON S. , GUNN G. J. , BLACKWELL A.
Published: November 2011

Culicoides biting midges (Diptera: Ceratopogonidae) vector a wide variety of internationally important arboviral pathogens of livestock and represent a widespread biting nuisance. This study investigated the influence of landscape, host and remotely‐sensed climate factors on local abundance of livestock‐associated species in Scotland, within a hierarchical generalized linear model framework. The Culicoides obsoletus group and the Culicoides pulicaris group accounted for 56% and 41%, respectively, of adult females trapped. Culicoides impunctatus Goetghebuer and C. pulicaris s.s. Linnaeus were the most abundant and widespread species in the C. pulicaris group (accounting for 29% and 10%, respectively, of females trapped). Abundance models performed well for C. impunctatus, Culicoides deltus Edwards and Culicoides punctatus Meigen (adjusted R2: 0.59–0.70), but not for C. pulicaris s.s. (adjusted R2: 0.36) and the C. obsoletus group (adjusted R2: 0.08). Local‐scale abundance patterns were best explained by models combining host, landscape and climate factors. The abundance of C. impunctatus was negatively associated with cattle density, but positively associated with pasture cover, consistent with this species' preference in the larval stage for lightly grazed, wet rush pasture. Predicted abundances of this species varied widely among farms even over short distances (less than a few km). Modelling approaches that may facilitate the more accurate prediction of local abundance patterns for a wider range of Culicoides species are discussed.
Lipoprotein biosynthesis by prolipoprotein diacylglyceryl transferase is required for efficient spore germination and full virulence of Bacillus anthracis
Authors: Okugawa Shu , Moayeri Mahtab , Pomerantsev Andrei P. , Sastalla Inka , Crown Devorah , Gupta Pradeep K. , Leppla Stephen H.
Published: November 2011

Bacterial lipoproteins play a crucial role in virulence in some Gram‐positive bacteria. However, the role of lipoprotein biosynthesis in Bacillus anthracis is unknown. We created a B. anthracis mutant strain altered in lipoproteins by deleting the lgt gene encoding the enzyme prolipoprotein diacylglyceryl transferase, which attaches the lipid anchor to prolipoproteins. 14C‐palmitate labelling confirmed that the mutant strain lacked lipoproteins, and hydrocarbon partitioning showed it to have decreased surface hydrophobicity. The anthrax toxin proteins were secreted from the mutant strain at nearly the same levels as from the wild‐type strain. The TLR2‐dependent TNF‐α response of macrophages to heat‐killed lgt mutant bacteria was reduced. Spores of the lgt mutant germinated inefficiently in vitro and in mouse skin. As a result, in a murine subcutaneous infection model, lgt mutant spores had markedly attenuated virulence. In contrast, vegetative cells of the lgt mutant were as virulent as those of the wild‐type strain. Thus, lipoprotein biosynthesis in B. anthracis is required for full virulence in a murine infection model.
Influence of Recovery Methods and Extenders on Bull Epididymal Spermatozoa Quality
Authors: Turri F , Madeddu M , Gliozzi TM , Gandini G , Pizzi F
Published: November 2011

Contents

The aim of this study was to compare the effects of two extraction methods in combination with two different extenders in bull epididymal sperm collection. Testes from 23 sexually mature Limousine bulls were collected at the abattoir. Epididymal sperm recovery was performed using both the float‐up (FL) and the retrograde flushing (RF) technique. Within extraction methods, half testes were processed with a Tris egg yolk extender and half with a Tris egg yolk‐free extender. Sperm concentration, motility, viability and morphology were evaluated. Sperm concentration was not significantly different between methods. Flushing technique was significantly better than the FL method in terms of sperm quality, considering total motility (80.3 ± 2.3% vs 71.6 ± 2.0%, p < 0.001, respectively) and viability (84.5 ± 1.5% vs 77.2 ± 1.3%, p < 0.001, respectively). Egg yolk influenced positively motility and morphology in the FL method, whereas decreased viability in flushed samples. Results suggest the use of the RF technique to collect cattle epididymal sperm.
Developmentally programmed, RNA‐directed genome rearrangement in Tetrahymena
Authors: Mochizuki Kazufumi
Published: November 2011

Developmentally programmed genome rearrangement has been observed in a variety of eukaryotes from vertebrates to worms to protists, and it provides an interesting exception to the general rule of the constancy of the genome. DNA elimination in the ciliated protozoan Tetrahymena is one of the most well‐characterized programmed genome rearrangement events. DNA elimination in the newly formed macronucleus of Tetrahymena is epigenetically regulated by the DNA sequence of the parental macronucleus. Dicer‐produced, Piwi‐associated small RNAs mediate this epigenetic regulation, probably through a whole‐genome comparison of the germline micronucleus to the somatic macronucleus. However, a correlation between small RNAs and programmed genome rearrangement could not be detected in the worm Ascaris suum. Therefore, different types of eukaryotes may have developed unique solutions to perform genome rearrangement.
Reflections on the practice of facilitating group‐based antenatal education: Should a midwife wear a uniform in the hospital setting?
Authors: Wisanskoonwong Peeranan , Fahy Kathleen , Hastie Carolyn
Published: November 2011

Wisanskoonwong P, Fahy K, Hastie C. International Journal of Nursing Practice 2011; 17: 628–635

Reflections on the practice of facilitating group‐based antenatal education: Should a midwife wear a uniform in the hospital setting?

The first author of this paper, a Thai midwife, conducted a feminist action research project aimed at collaboratively developing a model for group‐based antenatal education in Thailand. Should a midwife wear a uniform when facilitating midwife‐led group‐based antenatal education sessions in the hospital setting? This paper reports on a single example of reflection in and on midwifery practice that aimed to answer the guiding question. The practice and reflection occurred over a number of months at the beginning of the feminist action research project. The midwife should wear normal clothes when facilitating group‐based antenatal education as a symbol of equality in power relationships within the group. When power relationships between women and the midwife are equalized, women are more able to take responsibility for their health as they are less likely to defer to the ‘expert’. Reflection in and on practice is a powerful tool to allow the midwife to understand and change her own practice as required to meet those goals. Self‐change is a critical first step because there can be no change in the way maternity care is provided without each midwife being willing to be self‐aware and open to appropriate self‐change.
Developing risk management behaviours for nurses through medication incident analysis
Authors: Johnson Maree , Tran Duong Thuy , Young Helen
Published: November 2011

Johnson M, Tran DT, Young H. International Journal of Nursing Practice 2011; 17: 548–555

Developing risk management behaviours for nurses through medication incident analysis

The aim of this study was to define risk management behaviours related to medication safety. Mixed methods were used to analyze 318 nursing related medication incidents reported in an Australian metropolitan hospital. Most incidents did not result in patient harm (93%). Omission of medications was the most frequent often related to patient absences from the unit or nurses failing to sign for medications. Thematic analysis resulted in the Medication Safety Subscales including 29 behavioural statements within three domains—administering medications, storage and management of medications, managing adverse events related to medications. The Medication Safety Subscales can be used by managers, educators and clinicians to reinforce the importance of medication safety. Early action by nurses may reduce patient injury.
Fuels or microclimate? Understanding the drivers of fire feedbacks at savanna–forest boundaries
Authors: HOFFMANN WILLIAM A. , JACONIS SUSAN Y. , MCKINLEY KRISTEN L. , GEIGER ERIKA L. , GOTSCH SYBIL G. , FRANCO AUGUSTO C.
Published: November 2011

The higher flammability of tropical savanna, compared with forest, plays a critical role in mediating vegetation‐environment feedbacks, alternate stable states, and ultimately, the distribution of these two biomes. Multiple factors contribute to this difference in flammability, including microclimate, fuel amount and fuel type. To understand this transition in flammability, we studied fuel characteristics and microclimate across eight savanna–forest boundaries in south‐central Brazil. At each boundary, the environment was monitored for one week with automated measurements of near‐surface wind speed, air temperature, relative humidity and presence of dew. Manual measurements were performed to quantify fuel amounts and fuel moisture. These data were used to parameterize the fire behaviour model BehavePlus5 in order to simulate fire behaviour over the savanna–forest boundary. There were strong gradients across the boundary in all variables with the exception of total fuel load. During the day, savannas had higher wind speed and air temperature, and lower relative humidity and fuel moisture than forests. Although fuel loads were similar in savanna and forest, savanna was characterized by lower fuel bulk density, largely because of the presence of grasses. Based on these measurements, the fire behaviour model predicted savanna fires to be faster, more intense, and with greater flame lengths, relative to forest. A sensitivity analysis indicated that the primary cause of these differences was the low fuel bulk density characteristic of grassy fuels, with lesser contributions from wind speed, fuel moisture and total fuel load. These results indicate that the dominance of grassy fuels is the primary cause of the high flammability of savanna.
Ergonomic port placement in laparoscopic colorectal surgery
Authors: Muhlmann M. D. , Rodrigues S. J. , Wong S. W.
Published: November 2011

Aim  Port placement in laparoscopic surgery has important ergonomic implications. A manipulation angle (MA) of 60° has been shown to maximize task efficiency. We calculated the MA used during various stages of both right hemicolectomy (RH) and high anterior resection (AR).

Method  We compared two methods of port placement for each operation. RH‐PP1 included ports in the left iliac fossa and left upper quadrant. RH‐PP2 included ports suprapubically and in the left iliac fossa. We calculated the MA of each of these methods in mobilizing both the caecum and hepatic flexure. AR‐PP1 included ports in the right iliac fossa and right upper quadrant. AR‐PP2 included ports suprapubically and in the right iliac fossa. We calculated the MA of each of these methods in mobilizing the splenic flexure, descending–sigmoid junction and the recto–sigmoid junction.

Results  For RH‐PP1, the mean MA for mobilizing the caecum and hepatic flexure was 38° and 52°, respectively. For RH‐PP2, the mean MA for mobilising the caecum and hepatic flexure was 58° and 44°, respectively. For AR‐PP1, the mean MA for mobilizing the splenic flexure, the descending–sigmoid junction and the recto–sigmoid junction was 77°, 41° and 18°, respectively. For AR‐PP2, the mean MA for mobilizing the splenic flexure, the descending–sigmoid junction and the recto–sigmoid junction was 40°, 56° and 34°, respectively.

Conclusion  There are no two port placements that will allow for an ideal MA at every stage of mobilization for either right‐ or left‐sided resection.
Sources of Continuity and Change in Activity Level in Early Childhood
Authors: Saudino Kimberly J.
Published: November 2011

Actigraphs and parent and observer ratings were used to explore genetic influences on continuity and change in activity level (AL) in early childhood. Over 300 pairs of twins wore actigraphs for a 48‐hr period in the home and laboratory at ages 2 and 3. AL was genetically influenced at both ages with little evidence of differential heritability across age. For all measures, genetic influences contributed to phenotypic continuity. With the exception of the actigraph measure of AL in the home, new genetic effects emerged at age 3 indicating that genetic factors influence both continuity and change in AL in early childhood. Nonshared environmental influences were also a source of change in AL across the transition from infancy to early childhood.
A genotype–phenotype analysis of the 8q22.1 variant in migraine with aura
Authors: Esserlind A.‐L. , Kirchmann M. , Hauge A. W. , Le H. , Olesen J.
Published: November 2011

Background and purpose:  Although the genetics of familial hemiplegic migraine are being unraveled, this is not the case for the prevalent types of migraine. However, a recent genome wide association study (GWAS) reported an association of the single nucleotide polymorphism (SNP) rs1835740 and migraine. The aim of this study is to evaluate the association of clinical characteristics in migraine with aura (MA) with the newly discovered minor allele A of rs1835740 at 8q22.1.

Methods:  Participants were recruited from the Danish Headache Center and from specialist practices during the periods 1999–2002 and 2005–2006, and diagnosed according to the International Classification of Headache Disorders (ICHD‐II) using a validated physician‐conducted semi‐structured interview. A large number of clinical characteristics were systematically determined. Caucasians of Danish ancestry diagnosed with MA and successfully genotyped for the SNP rs1835740 were included. Patients with hemiplegic migraine were excluded. Blood samples were collected for extraction of genomic DNA and genotyped for the common susceptibility variant rs1835740.

Results:  Six hundred and ninety one successfully genotyped MA patients with substantial description of their clinical characteristics were included. Two hundred and fifty one were heterozygous and 40 were homozygote for the variant marker. Carriers of the rs1835740 variant showed a non‐significant tendency towards having a higher frequency of aura symptoms and a non‐significant tendency towards milder migraine headache characteristics and fewer accompanying symptoms. These tendencies were not increased in homozygote carriers.

Conclusion:  None of the clinical characteristics of MA were significantly influenced by the common susceptibility variant on 8q22.1.
Leadership in Interorganizational Networks: A Literature Review and Suggestions for Future Research
Authors: Müller‐Seitz Gordon
Published: November 2011

The present review is an investigation of the ways in which interorganizational networks coordinate their activities for the benefit of all parties. In this context ‘interorganizational networks’ consist of three or more separate, collaborating entities, and the question of their leadership has been well researched in a number of disciplines. Its interest to economic actors is growing. However, the findings of studies that have focused on leadership in such networks are somewhat incoherent. As demonstrated in the present review, this incoherence largely results from the consideration of different forms of network (e.g. hierarchical vs heterarchical), levels of analysis (e.g. organizational vs network), and terms used to describe the phenomena (e.g. governance or orchestration, quite apart from leadership). Against this background, the present review contributes to the body of knowledge on this topic in two main areas. First, the literature is reviewed in order to provide an overview of the key characteristics of forms of network and levels of analysis. Moreover, the view that leadership in such networks influences all members in order to ‘make things happen’ is suggested. Secondly, future avenues of research are identified in order to stimulate progress in this important area of study.
GENDER CONTEXT OF PERSONALISM IN BIOETHICS
Authors: AMZAT JIMOH , GRANDI GIOVANNI
Published: November 2011

Personalism is one of the philosophical perspectives which hold that the reality in person and the human person has the highest intrinsic value. This paper makes reference to Louis Janssens' eight criteria in adequate consideration of the human person but further argues that there is need to consider people as situated agents especially within gender relational perspectives. The paper identifies gender as an important social construction that shapes the consideration of the human persons within socio‐spatial spheres. The main crux of the paper is that there is a gender context of personalism and this has profound implications for bioethical agendas. Gender is part of the human condition, especially when we philosophically or sociologically engage the notion of equity and equality within the social system, because social realities in the relational perspective are not impartial, impersonal and equal. Gender does not determine morality but it plays a role in morality and expectations from moral agents. Women have been categorised as a sociological group because their integrity, freedom/autonomy and dignity (which are basic concerns of bioethics) are capable of being threatened. A gender perspective provides important incentives for moral theory which searches for possible conceptual imbalances or blind spots in ethical reflections. The paper refers to Sen's faces of gender inequality and expands on the notion that natality inequality is one of the fundamental levels of gender inequality, which in turn is the primary starting agenda in bioethics. The paper avers that the recognition of the fundamental importance of gender to the organization of social reality and the development of personal identities have important practical implications for bioethics.
The impact of inflammatory bowel disease post‐liver transplantation for primary sclerosing cholangitis
Authors: Joshi Deepak , Bjarnason Ingvar , Belgaumkar Ajay , O'Grady John , Suddle Abid , Heneghan Michael A. , Aluvihare Varuna , Rela Mohammed , Heaton Nigel , Agarwal Kosh
Published: November 2011

Background

An association between primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) is well recognized. However, the disease course of IBD following liver transplantation (LT) for PSC remains ill‐defined.

Aims and methods

We aimed to assess the impact of IBD in patients that had undergone LT for PSC to help identify risk factors for flare and to assess the impact of IBD on graft survival.

Results

110 patients underwent LT for PSC (Oct 1990‐Aug 2009) at King's College Hospital. 74 (67%) patients had concurrent IBD and 36 had PSC alone prior to transplant. 39 patients developed IBD (flare of IBD and de‐novo) post transplant. Cumulative risk for IBD at 1‐, 2‐, 5‐ and 10‐years was 16%, 24%, 38% and 72% respectively. Flare of IBD occurred in 33 patients with a mean time to flare of 30 ± 28 months. De‐novo IBD occurred in 6 patients (all UC). Mean time to diagnosis was 29 ± 25 months. Multivariate cox‐regression analysis identified active IBD at time of LT as a significant predictor of graft failure post LT (HR 10, CI 3‐39, P = 0.001) and smoking at time of transplantation and subsequent cessation predictive of recurrent IBD post transplantation (HR 17, 2‐180, P = 0.02).

Conclusion

In conclusion, smoking at time of LT was predictive of flare of IBD and active IBD at time of transplantation had a significant effect on graft survival. Medical therapy needs to be maximised in the pre‐LT period. Patients with poorly controlled IBD refractory to medical therapy should be considered for colectomy at time of transplantation.
High cell density attenuates reactive oxygen species: Implications for in vitro assays
Authors: Kim Dennis P. , Yahav Jonathan , Sperandeo Michael , Maloney Lauren , McTigue Monica , Lin Fubao , Clark Richard A.F.
Published: November 2011

In vitro cell‐based assays are an essential and universally used step in elucidation of biological processes as well as in drug development. However, results obtained depend on the validity of protocols used. This statement certainly pertains to in vitro assays of oxidative stress. The holy grail of in vitro models is reliability and predictability of outcomes that relate to a single variable like addition of hydrogen peroxide or xanthine oxidase. Without such validated outcomes, comparison of results among different laboratories is not possible. Achieving this goal requires a thorough understanding of the complex interplay between the cells, their environment, and the experimental assays. Furthermore, as this knowledge is attained, it must be disseminated and used to update and standardize existing protocols. Here, we confirm and extend the effect of pyruvate and cell density on in vitro oxidative stress assays. Cell viability was assessed using a colorimetric assay measuring the reduction of a tetrazolium salt (XTT) into a colored formazan dye. Extracellular hydrogen peroxide concentrations were measured using the foxp3 assay. We confirmed a previously reported finding that pyruvate, a common ingredient in cell culture media, acts as an extracellular scavenger of reactive oxygen species. We also demonstrated that cell density directly correlates with resistance to oxidative stress in tissue culture. It is theorized that the protective effect due to cell density predominantly relates to intracellular factors such as reduced glutathione and extracellular factors such as catalase.