bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble amyloid β-protein dimers isolated from Alzheimer cortex directly induce Tau hyperphosphorylation and neuritic degeneration
Authors: Jin Ming , Shepardson Nina , Yang Ting , Chen Gang , Walsh Dominic , Selkoe Dennis J.
Published: March 2011

Alzheimer disease is a major cause of cognitive failure, and a pathogenically related but more subtle process accounts for many cases of mild memory symptoms in older humans. Insoluble fibrillar plaques of amyloid β-proteins (Aβ) and neurofibrillary deposits of hyperphosphorylated tau proteins are the diagnostic lesions of AD, but their temporal mechanistic relationship has long been debated. The recent recognition that small, diffusible oligomers may be the principal bioactive form of Aβ raises the key question of whether these are sufficient to initiate cytoskeletal change and neurite degeneration. A few studies have examined the effects of oligomers of synthetic Aβ peptides of one defined length at supraphysiological concentrations, but the existence of such assemblies in the AD brain is not established. Here, we isolated Aβ dimers, the most abundant form of soluble oligomer detectable in the human brain, from the cortices of typical AD subjects and found that at subnanomolar concentrations, they first induced hyperphosphorylation of tau at AD-relevant epitopes in hippocampal neurons and then disrupted the microtubule cytoskeleton and caused neuritic degeneration, all in the absence of amyloid fibrils. Application of pure, synthetic dimers confirmed the effects of the natural AD dimers, although the former were far less potent. Knocking down endogenous tau fully prevented the neuritic changes, whereas overexpressing human tau accelerated them. Coadministering Aβ N-terminal antibodies neutralized the cytoskeletal disruption. We conclude that natural dimers isolated from the AD brain are sufficient to potently induce AD-type tau phosphorylation and then neuritic dystrophy, but passive immunotherapy mitigates this.
GPR124, an orphan G protein-coupled receptor, is required for CNS-specific vascularization and establishment of the blood–brain barrier
Authors: Cullen Mike , Elzarrad Mohammed K. , Seaman Steven , Zudaire Enrique , Stevens Janine , Yang Mi Young , Li Xiujie , Chaudhary Amit , Xu Lihong , Hilton Mary Beth , Logsdon Daniel , Hsiao Emily , Stein Erica V. , Cuttitta Frank , Haines Diana C. , Nagashima Kunio , Tessarollo Lino , St. Croix Brad
Published: March 2011

Every organ in the body requires blood vessels for efficient delivery of oxygen and nutrients, but independent vascular beds are highly specialized to meet the individual needs of specific organs. The vasculature of the brain is tightly sealed, with blood–brain barrier (BBB) properties developing coincident with neural vascularization. G protein-coupled receptor 124 (GPR124) (tumor endothelial marker 5, TEM5), an orphan member of the adhesion family of G protein-coupled receptors, was previously identified on the basis of its overexpression in tumor vasculature. Here, we show that global deletion or endothelial-specific deletion of GPR124 in mice results in embryonic lethality associated with abnormal angiogenesis of the forebrain and spinal cord. Expression of GPR124 was found to be required for invasion and migration of blood vessels into neuroepithelium, establishment of BBB properties, and expansion of the cerebral cortex. Thus, GPR124 is an important regulator of neurovasculature development and a potential drug target for cerebrovascular diseases.
The Nature of Dynamical Explanation
Authors: Zednik Carlos
Published: March 2011

The received view of dynamical explanation is that dynamical cognitive science seeks to provide covering-law explanations of cognitive phenomena. By analyzing three prominent examples of dynamicist research, I show that the received view is misleading: some dynamical explanations are mechanistic explanations and in this way resemble computational and connectionist explanations. Interestingly, these dynamical explanations invoke the mathematical framework of dynamical systems theory to describe mechanisms far more complex and distributed than the ones typically considered by philosophers. Therefore, contemporary dynamicist research reveals the need for a more sophisticated account of mechanistic explanation.
Reconceiving Eliminative Inference
Authors: Forber Patrick
Published: March 2011

Eliminative reasoning seems to play an important role in the sciences, but should it be part of our best theory of science? Statistical evidence, prevalent across the sciences, causes problems for eliminative inference, supporting the view that probabilistic theories of confirmation provide a better framework for reasoning about evidence. Here I argue that deductive elimination has an important inferential role to play in science, one that is compatible with probabilistic approaches to evidence. Eliminative inferences help frame testing problems, an essential step that determines the context for evaluating statistical evidence. I illustrate this process with examples from molecular evolutionary biology.
Bi-layer non-doped small-molecular white organic light-emitting diodes with high colour stability
Authors: Chen Shuming , Zhao Zujin , Wang Zhiming , Lu Ping , Gao Zhao , Ma Yuguang , Tang Ben Zhong , Kwok Hoi-Sing
Published: March 2011

Bi-layer non-doped white organic light-emitting diodes (WOLEDs) with hole-transporting layer 4-(4-(1,2,2-triphenylvinyl)phenyl)-7-(5-(4-(1,2,2-triphenylvinyl)phenyl)thiophen-2yl)benzo[c][1,2,5]thiadiazole (BTPETTD) as a red emitter and electron-transporting layer 4,4′-bis(1-phenyl-1H-phenanthro[9,10-d]imidazol-2-yl)biphenyl (DDPi) as a blue emitter are demonstrated. The blue emission is due to direct recombination of excitons in DPPi, while the red emission originates not only from the direct recombination of excitons in BTPETTD but also from a colour down-conversion process by absorbing blue emission and re-emitting red photons. The combination of blue emission and red emission yields an efficient and extremely stable white colour, regardless of driving voltages. In our demonstration, a bi-layer WOLED with an efficiency of 4.2 cd A−1 at 1000 cd m−2, 1931 Commision International de L'Eclairage coordinates of (0.31, 0.31) and a high colour rendering index of 92 over a wide range of driving voltages is obtained.
Characterization of the ion beam formed in a low magnetic field helicon mode
Authors: Lafleur T , Charles C , Boswell R W
Published: March 2011

An experimental characterization of the ion beam formed during a low magnetic field (<3 mT) helicon mode has been performed using a number of retarding field energy analysers, for pressures between 0.03 Pa < p
0 < 0.4 Pa in argon. The low-field helicon mode is formed over a narrow magnetic field range (1 mT < B
0 < 3 mT) using a single solenoid giving a strong diverging field, and is characterized by a distinct density peak. For pressures below about 0.3 Pa, an ion beam is observed in the downstream region of the plasma reactor, and its presence is directly correlated with that of the low-field mode, suggesting that the ion beam formation is induced by the appearance of the helicon mode. For the same pressure and rf power input, as the magnetic field is further increased, a second ion beam regime is observed for magnetic fields above 5 mT. In this second regime the plasma density is less than half that for the low-field mode, and the system seems most likely to be inductively coupled. A simple analytical model is developed to describe the general features and behaviour of the observed ion energy distribution functions as a function of the plasma potential profile and neutral gas pressure.
On zero-dimensionality and the connected component of locally pseudocompact groups
Authors: Dikranjan D. , Lukács Gábor
Published: March 2011

A topological group is locally pseudocompact if it contains a non-empty open set with pseudocompact closure. In this paper, we prove that if

G
G

is a group with the property that every closed subgroup of

G
G

is locally pseudocompact, then

G
0

G_0

is dense in the component of the completion of

G
G

, and

G

/

G
0

G/G_0

is zero-dimensional. We also provide examples of hereditarily disconnected pseudocompact groups with strong minimality properties of arbitrarily large dimension, and thus show that

G

/

G
0

G/G_0

may fail to be zero-dimensional even for totally minimal pseudocompact groups.
Hecke operators for non-congruence subgroups of Bianchi groups
Authors: Hamzeh Zarghani Saeid
Published: March 2011

We prove that the action of the Hecke operators on the cohomology of a finite index non-congruence subgroup

Γ
\Gamma

of a Bianchi group is essentially the same as the action of Hecke operators on the cohomology groups of

Γ
^

\hat {\Gamma }

, the congruence closure of

Γ
\Gamma

. This is a generalization of Atkin’s conjecture, first confirmed in a special case by Serre in

1987
1987

and proved in general by Berger in

1994
1994

.
Two remarks on the length spectrum of a Riemannian manifold
Authors: Schmidt Benjamin , Sutton Craig
Published: March 2011

We demonstrate that every closed manifold of dimension at least two admits smooth metrics with respect to which the length spectrum is not a discrete subset of the real line. In contrast, we show that the length spectrum of any real analytic metric on a closed manifold is a discrete subset of the real line. In particular, the length spectrum of any closed locally homogeneous space forms a discrete set.
Relating diameter and mean curvature for Riemannian submanifolds
Authors: Wu Jia-Yong , Zheng Yu
Published: March 2011

Given an

m
m

-dimensional closed connected Riemannian manifold

M
M

smoothly isometrically immersed in an

n
n

-dimensional Riemannian manifold

N
N

, we estimate the diameter of

M
M

in terms of its mean curvature field integral under some geometric restrictions, and therefore generalize a recent work of P. M. Topping in the Euclidean case (Comment. Math. Helv., 83 (2008), 539–546).
A nonconforming finite element method for fourth order curl equations in ℝ³
Authors: Zheng Bin , Hu Qiya , Xu Jinchao
Published: March 2011

In this paper we present a nonconforming finite element method for solving fourth order curl equations in three dimensions arising from magnetohydrodynamics models. We show that the method has an optimal error estimate for a model problem involving both

(
∇
×

)
2

(\nabla \times )^2

and

(
∇
×

)
4

(\nabla \times )^4

operators. The element has a very small number of degrees of freedom, and it imposes the inter-element continuity along the tangential direction which is appropriate for the approximation of magnetic fields. We also provide explicit formulae of basis functions for this element.
Mass-balanced randomization of metabolic networks
Authors: Basler Georg , Ebenhöh Oliver , Selbig Joachim , Nikoloski Zoran
Published: March 2011

Motivation: Network-centered studies in systems biology attempt to integrate the topological properties of biological networks with experimental data in order to make predictions and posit hypotheses. For any topology-based prediction, it is necessary to first assess the significance of the analyzed property in a biologically meaningful context. Therefore, devising network null models, carefully tailored to the topological and biochemical constraints imposed on the network, remains an important computational problem.

Results: We first review the shortcomings of the existing generic sampling scheme—switch randomization—and explain its unsuitability for application to metabolic networks. We then devise a novel polynomial-time algorithm for randomizing metabolic networks under the (bio)chemical constraint of mass balance. The tractability of our method follows from the concept of mass equivalence classes, defined on the representation of compounds in the vector space over chemical elements. We finally demonstrate the uniformity of the proposed method on seven genome-scale metabolic networks, and empirically validate the theoretical findings. The proposed method allows a biologically meaningful estimation of significance for metabolic network properties.

Contact:  basler@mpimp-golm.mpg.de; nikoloski@mpimp-golm.mpg.de

Supplementary Information:  Supplementary data are available at Bioinformatics online.
The Parrot as Paramour: Yourcenar's Amant Vert
Authors: Herdman Emma
Published: March 2011

This article argues that Marguerite Yourcenar's reference in
L'Œuvre au noir
to l'Amant Vert, the pet parrot belonging to Marguerite d'Autriche, should be read as contributing to the symbolism through which Yourcenar indicates Marguerite's bisexuality. The emergence and development of bisexuality as a theme in Yourcenar's characterization of Marguerite are first examined on their own terms. Next, this presentation of Marguerite is considered in the light of Yourcenar's sixteenth-century sources — Pierre Bourdeille, abbé de Brantôme's
Dames galantes
and Jean Lemaire de Belges's
Épîtres de l'Amant Vert
— in order to assess the historical validity of this presentation of parrots and of Marguerite d'Autriche. Finally, via reference to other sixteenth-century parrots, the article demonstrates that such symbolism is discernible in the sixteenth century, and therefore suggests that Yourcenar's Amant Vert is indicative of a highly perceptive and sensitive response to the period in which her novel is set.
From Fortune to Randomness in Seventeenth-Century Literature
Authors: Lyons John D.
Published: March 2011

This article proposes the view that during the course of the seventeenth century the concept of fortune in the Boethian mode, dominant in French literature during the Middle Ages, yielded to a new manner of conceiving the fortuitous. This new conception, still sometimes called ‘fortune’ but increasingly known as ‘hasard’, took the form of what we would call randomness. However, both the older and the newer ways of representing the fortuitous require awareness of individual human desire. In this study, Molière's
L'École des femmes
and two narratives by Marie-Madeleine de Lafayette,
Zayde
and
La Princesse de Clèves
, are considered with regard to the way the texts display chance either directly or indirectly. In conclusion, the article proposes the hypothesis that the shift from fortune to randomness in French literature is related to an increasing emphasis on what we call the reader's ‘identification’ with fictive characters.
Exit and entry of fishing vessels: an evaluation of factors affecting investment decisions in the North Sea English beam trawl fleet
Authors: Tidd Alex N. , Hutton Trevor , Kell Laurence T. , Padda Gurpreet
Published: March 2011

Tidd, A. N., Hutton, T., Kell, L. T., and Padda, G. 2011. Exit and entry of fishing vessels: an evaluation of factors affecting investment decisions in the North Sea English beam trawl fleet. – ICES Journal of Marine Science, 68: 961–971. A profitable fishery attracts additional effort (vessels enter), eventually leading to overcapacity and less profit. Similarly, fishing vessels exit depending on their economic viability (or reduced expectations of future benefits) or encouraged by schemes such as decommissioning grants and/or when there is consolidation of fishing effort within a tradable rights-based quota system (e.g. individual transferable quotas). The strategic decision-making behaviour of fishers in entering or exiting the English North Sea beam trawl fishery is analysed using a discrete choice model by integrating data on vessel characteristics with available cost data, decommissioning grant information, and other factors that potentially influence anticipated benefits or future risks. It is then possible to predict whether operators choose to enter, stay, exit, or decommission. Important factors affecting investment include vessel age and size, future revenues, operating costs (e.g. fuel), stock status of the main target species, and the impact of management measures (e.g. total allowable catches) and total fleet size (a proxy for congestion). Based on the results, the predicted marginal effects of each factor are presented and the impact of each is discussed in the context of policies developed to align fleet capacity with fishing opportunities.
Gamma‐glutamyl Transferase Is Strongly Associated With Degree of Overweight and Sex
Authors: Wiegand Susanna , Thamm Michael , Kiess Wieland , Körner Antje , Reinehr Thomas , Krude Heiko , Hoffmeister Ulrike , Holl Reinhard W ,   APV Study Group and the German Competence Network Adipositas
Published: March 2011

Gamma‐glutamyl transferase (GGT) is a marker for cardiovascular risk and an independent predictor of long‐term outcome in adults. Epidemiological data from pediatric cohorts are rare. We studied the association of GGT to body mass index as a standard deviation score, sex, and age in 68,415 children (age 11.7 ± 4.4 years; 48% boys; body mass index 27.2 ± 7.4 kg/m2; GGT measured in n = 23,955). GGT >50 U/L is strongly associated with extreme obesity (odds ratio 27.13, 95% confidence interval 15.07–48.85) and male sex (odds ratio 2.60, 95% confidence interval 2.03–3.31). GGT seems to be of clinical relevance and may be marketable as a surrogate in risk profiling for children with obesity.
Gastroesophageal Reflux in Young Children Treated for Esophageal Atresia: Evaluation With pH‐Multichannel Intraluminal Impedance
Authors: Catalano Pieralba , Di Pace Maria R , Caruso Anna M , Casuccio Alessandra , De Grazia Enrico
Published: March 2011

Objectives:

Gastroesophageal reflux (GER) and dismotility occur frequently after repair of esophageal atresia (EA). GER‐associated complications can manifest either early or later; then precocious diagnosis and treatment are essential. The aim of the study was to evaluate characteristics of GER and esophageal clearance in children treated for EA with distal tracheoesophageal fistula, using pH‐multichannel intraluminal impedance (pH‐MII).

Patients and Methods:

Twenty‐two children (ages 3–40 months) treated for EA at birth, and 20 normal children of similar age with suspected GER disease were included in the study. Impedance parameters were analyzed according to age and symptoms.

Results:

Reflux events were mainly nonacidic. About bolus exposure index, mean acid clearing time (MACT), and mean bolus clearing time (MBCT), a significant difference was found between 2 groups: the median MACT and MBCT were longer, with values of 281 and 39 seconds, respectively, in the EA group and 110 and 15 seconds in the control group (P < 0.0005).

Conclusions:

Our data show that in young patients the majority of refluxes are not acid. This implies that the incidence of GER may be underestimated if pH‐metry is used. The pH‐MII is an ideal test in children because it studies both GER with its characteristics and motility pattern. The quality of reflux does not seem to influence the onset of symptoms that are related to an impaired esophageal clearance. Hence, this technique could be useful to study patients treated for EA, avoiding the onset of complications.
Heat waves and phonon–wall collisions in nanowires
Authors: Jou D. , Sellitto A. , Alvarez F. X.
Published: March 2011

The dispersion relation of heat waves along nanowires is obtained, displaying the influence of the roughness of the walls. This knowledge may be useful for the development of new experimental techniques based on heat waves, complementary to current steady-state measurements, for the exploration of phonon–wall collisions in smooth and rough walls.
How parasitoid females produce sexy sons: a causal link between oviposition preference, dietary lipids and mate choice in
Nasonia
Authors: Blaul Birgit , Ruther Joachim
Published: March 2011

Sexual selection theory predicts that phenotypic traits used to choose a mate should reflect honestly the quality of the sender and thus, are often costly. Physiological costs arise if a signal depends on limited nutritional resources. Hence, the nutritional condition of an organism should determine both its quality as a potential mate and its ability to advertise this quality to the choosing sex. In insects, the quality of the offspring's nutrition is often determined by the ovipositing female. A causal connection, however, between the oviposition decisions of the mother and the mating chances of her offspring has never been shown. Here, we demonstrate that females of the parasitic wasp
Nasonia vitripennis
prefer those hosts for oviposition that have been experimentally enriched in linoleic acid (LA). We show by
13
C-labelling that LA from the host diet is a precursor of the male sex pheromone. Consequently, males from LA-rich hosts produce and release higher amounts of the pheromone and attract more virgin females than males from LA-poor hosts. Finally, males from LA-rich hosts possess three times as many spermatozoa as those from LA-poor hosts. Hence, females making the right oviposition decisions may increase both the fertility and the sexual attractiveness of their sons.
Candida albicans adhesin Als3p is dispensable for virulence in the mouse model of disseminated candidiasis
Authors: Cleary Ian A. , Reinhard Sara M. , Miller C. Lindsay , Murdoch Craig , Thornhill Martin H. , Lazzell Anna L. , Monteagudo Carlos , Thomas Derek P. , Saville Stephen P.
Published: March 2011

The presence of specific proteins, including Ece1p, Hwp1p and Als3p, distinguishes theCandida albicanshyphal cell wall from that of yeast-form cells. These proteins are thought to be important for the ability ofC. albicanscells to adhere to living and non-living surfaces and for the cell-to-cell adhesion necessary for biofilm formation, and also to be pivotal in mediatingC. albicansinteractions with endothelial cells. Using anin vitroflow adhesion assay, we previously observed that yeast cells bind in greater numbers to human microvascular endothelial cells than do hyphal or pseudohyphal cells. This is consistent with previous observations that, in a murine model of disseminated candidiasis, cells locked in the yeast form can efficiently escape the bloodstream and invade host tissues. To more precisely explore the role of Als3p in adhesion and virulence, we deleted both copies ofALS3in a wild-typeC. albicansstrain. In agreement with previous studies, ourals3Δ null strain formed hyphae normally but was defective in biofilm formation. WhilstALS3was not expressed in our null strain, hypha-specific genes such asECE1andHWP1were still induced appropriately. Both the yeast form and the hyphal form of theals3Δ strain adhered to microvascular endothelial cells to the same extent as a wild-type strain under conditions of flow, indicating that Als3p is not a significant mediator of the initial interaction between fungal cells and the endothelium. Finally, in a murine model of haematogenously disseminated candidiasis the mutantals3Δ remained as virulent as the wild-type parent strain.
Cognitive and neural determinants of response strategy in the dual-solution plus-maze task
Authors: De Leonibus Elvira , Costantini Vivian J. A. , Massaro Antonio , Mandolesi Georgia , Vanni Valentina , Luvisetto Siro , Pavone Flaminia , Oliverio Alberto , Mele Andrea
Published: March 2011

Response strategy in the dual-solution plus maze is regarded as a form of stimulus-response learning. In this study, by using an outcome devaluation procedure, we show that it can be based on both action-outcome and stimulus-response habit learning, depending on the amount of training that the animals receive. Furthermore, we show that deactivation of the dorso-medial and the dorso-lateral striatum with Botulinum neurotoxin A, mimicked or abolished, respectively, the effects of practice on the sensitivity of the response strategy to outcome devaluation. These findings have relevant implications for the understanding of the learning mechanisms underlying different overt behaviors in this widely used maze task.
Functional Diversity of Isoamylase Oligomers: The ISA1 Homo-Oligomer Is Essential for Amylopectin Biosynthesis in Rice Endosperm
Authors: Utsumi Yoshinori , Utsumi Chikako , Sawada Takayuki , Fujita Naoko , Nakamura Yasunori
Published: March 2011

Rice (Oryza sativa) endosperm has two isoamylase (ISA) oligomers, ISA1 homo-oligomer and ISA1-ISA2 hetero-oligomer. To examine their contribution to starch synthesis, expression of the ISA1 or ISA2 gene was differently regulated in various transgenic plants. Although suppression of ISA2 gene expression caused the endosperm to have only the homo-oligomer, no significant effects were detected on the starch phenotypes. In contrast, ISA2 overexpression led to endosperm having only the hetero-oligomer, and starch synthesis in the endosperm was drastically impaired, both quantitatively and qualitatively, because the starch was devoid of typical starch features, such as thermal and x-ray diffraction properties, and water-soluble highly branched maltodextrins were accumulated. In the ISA2 overexpressed line, about 60% to 70% of the ISA1-ISA2 hetero-oligomer was bound to starch, while the ISA homo- and hetero-oligomers from the wild type were mostly present in the soluble form at the early milking stage of the endosperm. Detailed analysis of the relative amounts of homo- and hetero-oligomers in various lines also led us to the conclusion that the ISA1 homo-oligomer is essential, but not the ISA1-ISA2 oligomer, for starch production in rice endosperm. The relative amounts of ISA1 and ISA2 proteins were shown to determine the ratio of both oligomers and the stoichiometry of both ISAs in the hetero-oligomer. It was noted when compared with the homo-oligomer that all the hetero-oligomers from rice endosperm and leaf and potato (Solanum tuberosum) tuber were much more stable at 40°C. This study provides substantial data on the structural and functional diversity of ISA oligomers between plant tissues and species.
Relative performance of common biochemical indicators in detecting cigarette smoking
Authors: Marrone Gina F. , Shakleya Diaa M. , Scheidweiler Karl B. , Singleton Edward G. , Huestis Marilyn A. , Heishman Stephen J.
Published: March 2011

Aims  Many cities have banned indoor smoking in public places. Thus, an updated recommendation for a breath carbon monoxide (CO) cut‐off is needed that optimally determines smoking status. We evaluated and compared the performance of breath CO and semiquantitative cotinine immunoassay test strips (urine and saliva NicAlert®) alone and in combination.

Design  Cross‐sectional study.

Setting  Urban drug addiction research and treatment facility.

Participants  Ninety non‐treatment‐seeking smokers and 82 non‐smokers.

Measurements  Participants completed smoking histories and provided breath CO, urine and saliva specimens. Urine and saliva specimens were assayed for cotinine by NicAlert® and liquid chromatography‐tandem mass spectrometry (LCMSMS).

Findings  An optimal breath CO cut‐off was established using self‐report and LCMSMS analysis of cotinine, an objective indicator, as reference measures. Performance of smoking indicators and combinations were compared to the reference measures. Breath CO ≥5 parts per million (p.p.m.) optimally discriminated smokers from non‐smokers. Saliva NicAlert® performance was less effective than the other indicators.

Conclusions  In surveys of smokers and non‐smokers in areas with strong smoke‐free laws, the breath carbon monoxide cut‐off that discriminates most effectively appears to be ≥5 p.p.m. rather than the ≥10 p.p.m. cut‐off often used. These findings may not generalize to clinical trials, regions with different carbon monoxide pollution levels or areas with less stringent smoke‐free laws.
Merapi (Java, Indonesia): anatomy of a killer volcano
Authors: Gertisser R. , Charbonnier S.J. , Troll V.R. , Keller J. , Preece K. , Chadwick J.P. , Barclay J. , Herd R.A.
Published: March 2011

Merapi is Indonesia's most dangerous volcano with a history of deadly eruptions. Over the past two centuries, the volcanic activity has been dominated by prolonged periods of lava dome growth and intermittent gravitational or explosive dome failures to produce pyroclastic flows every few years. Explosive eruptions, such as in 2010, have occurred occasionally during this period, but were more common in pre‐historical time, during which a collapse of the western sector of the volcano occurred at least once. Variations in magma supply from depth, magma ascent rates and the degassing behaviour during ascent are thought to be important factors that control whether Merapi erupts effusively or explosively. A combination of sub‐surface processes operating at relatively shallow depth inside the volcano, including complex conduit processes and the release of carbon dioxide into the magmatic system through assimilation of carbonate crustal rocks, may result in unpredictable explosive behaviour during periods of dome growth. Pyroclastic flows generated by gravitational or explosive lava dome collapses and subsequent lahars remain the most likely immediate hazards near the volcano, although the possibility of more violent eruptions that affect areas farther away from the volcano cannot be fully discounted. In order to improve hazard assessment during future volcanic crises at Merapi, we consider it crucial to improve our understanding of the processes operating in the volcano's plumbing system and their surface manifestations, to generate accurate hazard zonation maps that make use of numerical mass flow models on a realistic digital terrain model, and to utilize probabilistic information on eruption recurrence and inundation areas.
Rescue palaeontology
Authors: Edwards Dee , Williams Dave
Published: March 2011

A technique for replicating large rock outcrops has been developed so that casts of these surfaces can be archived in their present stage of preservation. Researchers can then study these casts in the laboratory under optimum lighting conditions, sometimes revealing new fossil evidence, while students and members of the public can be shown geological features that might otherwise be inaccessible to them.
The development and testing of a scale of Taiwanese caregiver meaning
Authors: Yen Wen‐Jiuan , Ma Wei‐Fen , Lu Ying‐Chi , Chang Ting , Lee Sheuan
Published: March 2011

Aims.  The purpose of this study was to develop and test a scale of Taiwanese caregiver meaning.

Background.  The meaning of care‐giving is defined as the beliefs one holds about oneself and the care‐giving experiences that affect adjustment to the care‐giving role. An existing tool, the Meaning in Care‐giving Scale, has been tested in Taiwan, but it showed that the construct validity was unreliable.

Design.  The study was a cross‐sectional study with purposive sampling.

Method.  The instrument was developed through 20 semi‐structured interviews of caregivers of mentally ill patients. A comparative method was used to analyse the text and field notes. According to the results, 29 items were designed and 318 caregivers of mentally ill patients were recruited from a psychiatric outpatient department in central Taiwan. Content and back direct content validity tests were conducted. Internal consistency, Chronbach’s alpha, was used to examine the reliability, and exploratory factor analysis was used to examine the construct validity.

Results.  Twenty items were kept after exploratory factor analysis. They represent four factors: the benefits of care‐giving, a belief in Karma, personal responsibility and a reflection on life. Cronbach’s alpha value for a subscale increased from 0·68–0·84, and the total scale was 0·84. A sixty per cent (59·55%) cumulative variance can be explained by four factors.

Conclusion.  A Taiwanese caregiver meaning can be considered a useful scale for assessing the meaning of care‐giving for Taiwanese caregivers of mentally ill patients. A good scale and instrument take years to develop. This study takes the first step to examine the structure of the scale, and it is worth continued testing, modification and improvements.

Relevance to clinical practice.  The scale of Taiwanese caregiver meaning was developed based on certain aspects of contemporary Taiwanese culture. It can be used to provide mental health professionals new counselling knowledge to assist caregivers of mentally ill patients to adjust to their circumstances.
Barriers to clinical leadership development: findings from a national survey
Authors: Fealy Gerard M , McNamara Martin S , Casey Mary , Geraghty Ruth , Butler Michelle , Halligan Phil , Treacy Margaret , Johnson Maree
Published: March 2011

Aims and objectives.  To describe self‐reported barriers to clinical leadership development among nurses and midwives in Ireland.

Background.  Effective clinical leadership is essential for optimising care and improving patient outcomes. Clinical leadership development is concerned with intrapersonal and interpersonal capabilities and is context bound. Barriers to clinical leadership development among nurses and midwives are associated with interdisciplinary and organisational factors, such as lack of influence in interdisciplinary care planning and policy.

Design.  A national postal survey of nurses and midwives was administered to a simple random sample of 3000 nurses and midwives in Ireland.

Method.  The method of data collection was the Clinical Leadership Analysis of Need Questionnaire (CLAN‐Q) Barriers Scale (CLAN‐QBS©), a self‐administered, self‐report questionnaire developed to measure the barriers to clinical leadership development.

Results.  Mean scores for the CLAN‐Q barriers subscales showed that barriers to clinical leadership development were perceived as lower in the dimension ‘quality care factors’, when compared with the dimensions ‘interdisciplinary relationships, recognition and influence’. Staff and other promotional grades differed significantly in self‐perceived barriers related to interdisciplinary working, influence and recognition of the disciplinary contribution.

Conclusions.  Differential experiences of barriers among higher and lower grades suggest that grade level may influence ability to negotiate work‐related and organisational barriers to clinical leadership development.

Relevance to clinical practice.  Overcoming the barriers to clinical leadership development requires attention to interdisciplinary relationships in the practicum and to the actual and perceived degree of relative influence that nurses and midwives have at wider departmental and organisational levels.
An initial look at the quality of life of Malaysian families that include children with disabilities
Authors: Clark M. , Brown R. , Karrapaya R.
Published: March 2011

Background  While there is a growing body of literature in the quality of life of families that include children with disabilities, the majority of research has been conducted in western countries. The present study provides an initial exploration of the quality of life of Malaysian families that include children with developmental/intellectual disabilities. Dynamics characterising Malaysian society are described as developments in social policy and service delivery that support persons with disabilities and their families.

Method  Questionnaire data were collected using the Family Quality of Life Survey – Short Version. Members of 52 families that included one or two children with disabilities were interviewed. Their responses provided their perceptions within six dimensions of family quality of life across the nine life domains assessed.

Results  Findings showed a consistent pattern of relatively strong perceived ‘importance’ ratings in each of life domains as compared to mean ratings for other family quality of life dimensions. Some dimensions of family quality of life, in particular ‘opportunities’, ‘initiative’ and ‘attainment’, demonstrated particularly strong associations with each other. Overall means of satisfaction with and attainment of family quality of life as well as global evaluations of quality of life and satisfaction all demonstrated significant associations, although each of these correlations accounted for less than 50% of the common variance.

Conclusions  The importance rating can be viewed as a determining factor in terms of quality of life, and it played a critical role in supporting attainment of, and satisfaction with, family quality of life, assuming opportunities, initiative and stability are adequate. The need for a broader sample including families that were not receiving services was noted. Future research questions based on the results of the current study and some of the dynamics impacting Malaysian society are also suggested.
Home literacy environments, interest in reading and emergent literacy skills of children with Down syndrome versus typical children
Authors: Ricci L.
Published: March 2011

Background  The present study examined home literacy environments, children's interest in reading and emergent literacy skills of pre‐school‐aged children with Down syndrome (DS; n = 20), school‐aged children with DS (n = 17) and typically developing children (n = 18) matched on chronological age with the younger DS group and mental age (MA) with the older DS group.

Method  Parents filled out questionnaires on their home literacy environments and their children's interest in reading. School‐aged children with DS and typical children were assessed on cognitive functioning, receptive vocabulary, alphabet knowledge, familiarity with print conventions and comprehension of meaning.

Results  School‐aged children with DS and typical children – as opposed to pre‐school‐aged children with DS – were exposed to more literacy‐rich home environments and had greater interest in reading. School‐aged children with DS also outperformed the MA‐matched typical group on letter and sight word knowledge and familiarity with print conventions.

Conclusions  Parents of children with DS tailor home literacy environments to their children's developmental levels. Confirming earlier studies, children with DS achieved some higher literacy skills than what was expected for their MA, emphasising the importance of early reading interventions for this population.
Life without the essential bacterial tRNAIle2–lysidine synthetase TilS: a case of tRNA gene recruitment in Bacillus subtilis
Authors: Fabret Céline , Dervyn Etienne , Dalmais Bérengère , Guillot Alain , Marck Christian , Grosjean Henri , Noirot Philippe
Published: March 2011

In eubacteria, the post‐transcriptional modification of the wobble cytidine of the CAU anticodon in a precursor tRNAIle2 to a lysidine residue (2‐lysyl‐cytidine, abbreviated as L) allows the amino acid specificity to change from methionine to isoleucine and the codon decoding specificity to shift from AUG to AUA. The tilS gene encoding the enzyme that catalyses this modification is widely distributed. However, some microbial species lack a tilS gene, indicating that an alternative strategy exists to accurately translate the AUA codon into Ile. To determine whether a TilS‐dependent bacterium, such as Bacillus subtilis, can overcome the absence of lysidine in its tRNAIle2 (CAU), we analysed the suppressor mutants of a tilS‐thermosensitive allele. These tilS‐suppressor mutants carry a substitution of the wobble guanosine into thymidine in one of the tRNAIle1 genes (the original GAT anticodon is changed to a TAT). In absence of TilS activity, the AUA codons are translated into isoleucine by the suppressor tRNAIle1, although a low level of AUA codons is also mistranslated into methionine. Results are in agreement with rare cases of eubacteria (and archaea), which naturally lack the tilS gene (or tiaS in archaea) but contain a tRNAIle2 gene containing a TAT instead of a CAT anticodon.
In Vitro Developmental Potential of Nuclear Transfer Embryos Cloned with Enucleation Methods using Pre‐denuded Bovine Oocytes
Authors: Jeon B‐G , Betts DH , King WA , Rho G‐J
Published: March 2011

Contents

Enucleation of a recipient oocyte is an important essential process in the procedure of somatic cell nuclear transfer (SCNT). The present study investigated a method for the improvement of enucleation efficiency. Oocytes were denuded of cumulus cells before the completion of nuclear maturation (pre‐denuded) after 12 h of culture at MI stage and subsequently cultured for additional 6 h until the completion of nuclear maturation and extrusion of the first polar body (PB1). The extrusion rate of PB1 was not significantly different in the pre‐denuded oocyte group, compared with control oocyte group matured for 18 h. However, the number of oocytes showing the metaphase II (MII) located just underneath the PB1 was significantly higher (p < 0.05) in the pre‐denuded oocyte group than those in control oocyte group. To test the effect of pre‐denuding on the enucleation rate and developmental potential of embryos to blastocyst stage, subsequent somatic cell nuclear transfer comparisons were made with three different methods of enucleation at MII stage using vital dyes (demicoline and Hoescht) or the PB1 (blind enucleation) to localize the chromosome plate. Enucleation rate of the oocytes with demicoline, Hoechst and pre‐denuding enucleation groups were significantly higher (p < 0.05) than those of blind enucleation groups. However, cleavage rate to two‐cell stage and, developmental rate to blastocyst and hatched blastocyst stage, the mean numbers of total and ICM cells in the SCNT embryos with Hoechst enucleation groups were significantly decreased (p < 0.05), compared to those of blind, demicoline and pre‐denuding enucleation groups. Moreover, the level of telomerase activity was also significantly (p < 0.05) decreased in SCNT blastocysts of Hoechst enucleation group, compared to those of blind, demicoline and pre‐denuding enucleation groups. Taken together, pre‐denuding enucleation group using pre‐denuded oocytes was a useful and simple enucleation method for bovine SCNT embryos.
The SOMERS Index: A simple instrument designed to predict the likelihood of rural career choice
Authors: Somers George T. , Jolly Brian , Strasser Roger P.
Published: March 2011

Objective:  The World Health Organization has drawn up a set of strategies to encourage health workers to live and work in remote and rural areas. A comprehensive instrument designed to evaluate the effectiveness of such programs has not yet been tested. Factors such as Stated rural intention, Optional rural training, Medical sub‐specialization, Ease (or self‐efficacy) and Rural Status have been used individually or in limited combinations. This paper examines the development, validity, structure and reliability of the easily‐administered SOMERS Index.

Design:  Limited literature review and cross‐sectional cohort study.

Setting:  Australian medical school.

Participants:  A total of 345 Australian undergraduate‐entry medical students in years 1 to 4 of the 5‐year course.

Main outcome measures:  Validity of the factors as predictors of rural career choice was sought in the international literature. Structure of the index was investigated through Principal Components Analysis and regression modelling. Cronbach's alpha was the test for reliability.

Results:  The international literature strongly supported the validity of the components of the index. Factor analysis revealed a single, strong factor (eigenvalue: 2.78) explaining 56% of the variance. Multiple regression modelling revealed that each of the other variables contributed independently and strongly to Stated Rural Intent (semi‐partial correlation coefficients range: 0.20–0.25). Cronbach's alpha was high at 0.78.

Conclusions:  This paper presents the reliability and validity of an index, which seeks to estimate the likelihood of rural career choice. The index might be useful in student selection, the allocation of rural undergraduate and postgraduate resources and the evaluation of programs designed to increase rural career choice.
Management of chronic Hepatitis B infection in the remote primary health care setting: The search for a suitable guideline
Authors: Cross Virginia , Larkins Sarah
Published: March 2011

Objective:  To identify a regionally appropriate guideline for the primary health care management of chronic Hepatitis B patients in the Torres Strait.

Design:  Literature review. PubMed (1950–November 2009), Nursing and allied health (CINAHL)‐CD (1982–November 2009), and the following databases accessed through INFORMIT: Australian Public Affairs Information Service – Health (1978–November 2009), Aboriginal and Torres Strait Health Bibliography (1900–November 2009), Health & Society Database (1980–November 2009), Health Collection (1980–November 2009), Meditext (1968–November 2009), and Rural and Remote Health Database (1966–January 2006) were searched over a 3‐month period from September to November 2009. An Internet search of relevant guidelines and recommendations from professional bodies such as the World Health Organization was also performed.

Setting:  Remote primary health care.

Outcome measures:  Initial searching identified 144 articles to include based on the provision of recommendations or guidelines for management of Hepatitis B at the primary care level. Included articles were then reviewed for their appropriateness to the remote primary health care setting against a set of five criteria determined at a consensus meeting of eight local medical officers.

Results:  Eleven articles were included for final review of which none met all five criteria of appropriateness for the remote primary health care setting.

Conclusions:  Guidelines need to recognize the difficulties of rural and remote practice and present practical alternatives to urban centred recommendations.
Atypical social development in neonatal intensive care unit survivors at 12 months
Authors: Yamada Yasumasa , Yoshida Futoshi , Hemmi Hayato , Ito Miharu , Kakita Hiroki , Yoshikawa Toru , Hishida Manabu , Iguchi Toshiyuki , Seo Tomoko , Nakanishi Keiko
Published: March 2011

Background:  Owing to advances in neonatal intensive care, many infants who are hospitalized in neonatal intensive care units (NICU) can survive and grow, and are referred to as NICU survivors. However, social development in NICU survivors has not been fully explored.

Methods:  To examine the social development of NICU survivors, a questionnaire consisting of the Modified Checklist for Autism in Toddlers (M‐CHAT) was used. The M‐CHAT was completed by the parents of either NICU survivors (n= 117) or normally delivered children (control group, n= 112) during their regular medical checkups at a corrected age of 12 months.

Results:  Ninety percent of NICU survivors and 63% of control children did not pass the M‐CHAT screen. As it was originally designed for children aged 18–30 months, failed M‐CHAT items could have been due to developmental issues and not due to autistic spectrum disorders. However, there was a significant difference in the total number of items failed between the two groups. In particular, many NICU survivors did not pass on M‐CHAT items, such as oversensitivity to noise, unusual finger movements, and attempts to attract attention. Concerning perinatal complications, infants with low birthweight and/or the need for respiratory support tended to have a higher number of failures on all M‐CHAT items.

Conclusions:  NICU survivors may have distinct developmental patterns of social communication, and should be followed up for assessment of social skills and neurological development.
Outside of the intensive care unit: the safety and effectiveness of an insulin–dextrose infusion protocol
Authors: Wong V. W. , Kok J. , Eason M.
Published: March 2011

A review of patients who were on an insulin–dextrose (I‐D) infusion protocol in general hospital wards over a 6‐month period was conducted to compare glycaemic control before, during and following I‐D infusion. Among the 34 cases identified, blood glucose levels during the period of I‐D infusion were significantly better than those before or after I‐D infusion. This I‐D infusion protocol was shown to be effective and safe in maintaining good glycaemic control for patients outside intensive care unit.