bluuebunny/crossref_metadata_2025 huggingface dataset:
Carrier transport mechanisms of nonvolatile write-once-read-many-times memory devices with InP–ZnS core-shell nanoparticles embedded in a polymethyl methacrylate layer
Authors: Ham Jung Hoon , Oh Do Hyun , Cho Sung Hwan , Jung Jae Hun , Kim Tae Whan , Ryu Eui Dock , Kim Sang Wook
Published: March 2009

Current-voltage (I-V) curves at 300 K for Al/InP–ZnS nanoparticles embedded in a polymethyl methacrylate layer/Al devices showed electrical bistability for write-once-read-many-times (WORM) memory devices. From the I-V curves, the ON/OFF ratio for the device with InP–ZnS nanoparticles was significantly larger than that for the device without InP–ZnS nanoparticles, indicative of the existence of charge capture in the InP nanoparticles. The estimated retention time of the ON state for the WORM memory device was more than 10 years. The carrier transport mechanisms for the WORM memory devices are described by using several models to fit the experimental I-V data.
Deep ultraviolet photoluminescence of Tm-doped AlGaN alloys
Authors: Nepal N. , Zavada J. M. , Lee D. S. , Steckl A. J. , Sedhain A. , Lin J. Y. , Jiang H. X.
Published: March 2009

The ultraviolet (UV) photoluminescence (PL) properties of Tm-doped AlxGa1−xN (0.39≤x≤1) alloys grown by solid-source molecular beam epitaxy were probed using above-bandgap excitation from a laser source at 197 nm. The PL spectra show dominant UV emissions at 298 and 358 nm only for samples with x=1 and 0.81. Temperature dependence of the PL intensities of these emission lines reveals exciton binding energies of 150 and 57 meV, respectively. The quenching of these UV emissions appears related to the thermal activation of the excitons bound to rare-earth structured isovalent (RESI) charge traps, which transfer excitonic energy to Tm3+ ions resulting in the UV emissions. A model of the RESI trap levels in AlGaN alloys is presented.
Dislocation core effect scattering in a quasitriangle potential well
Authors: Xu Xiaoqing , Liu Xianglin , Yang Shaoyan , Liu Jianming , Wei Hongyuan , Zhu Qinsheng , Wang Zhanguo
Published: March 2009

A theory of scattering by charged dislocation lines in a quasitriangle potential well of AlxGa1−xN/GaN heterostructures is developed. The dependence of mobility on carrier sheet density and dislocation density is obtained. The results are compared with those obtained from a perfect two-dimensional electron gas and the reason for discrepancy is given.
Cathodoluminescence study of dislocation-related luminescence from small-angle grain boundaries in multicrystalline silicon
Authors: Lee Woong , Chen Jun , Chen Bin , Chang Jiho , Sekiguchi Takashi
Published: March 2009

Dislocation-related luminescence from small-angle grain boundaries (SA-GBs) in multicrystalline Si was investigated by cathodoluminescence. D3 and D4 emissions were detected at SA-GBs with a misorientation angle of around 1°–1.5°, and D1 and D2 at SA-GBs with a misorientation angle of around 2°–2.5°. Electron beam-induced current investigations indicate that the former SA-GBs possess only shallow energy levels, while the latter possess both deep and shallow levels. The origins of D-line luminescence at SA-GBs are discussed in terms of dislocation structures.
Kinetically controlled, adhesiveless transfer printing using microstructured stamps
Authors: Kim Tae-Ho , Carlson Andrew , Ahn Jong-Hyun , Won Sang Min , Wang Shuodao , Huang Yonggang , Rogers John A.
Published: March 2009

This letter describes the physics and application of an approach to transfer printing that uses stamps with microstructures of relief embossed into their surfaces. Experimental measurement of velocity-dependent adhesive strength as a function of relief geometry reveals key scaling properties and provides a means for comparison to theoretical expectation. Formation of transistor devices that use nanoribbons of silicon transfer printed directly onto glass substrates without adhesive layers demonstrates the use of this type of approach for a high-performance (mobilities >325 cm2/V s and on/off ratios >105) single crystal silicon on glass technology.
Tomographic study of atomic-scale redistribution of platinum during the silicidation of Ni0.95Pt0.05/Si(100) thin films
Authors: Adusumilli Praneet , Lauhon Lincoln J. , Seidman David N. , Murray Conal E. , Avayu Ori , Rosenwaks Yossi
Published: March 2009

Atom-probe tomography was utilized to study the distribution of Pt after silicidation of a solid-solution Ni0.95Pt0.05 thin film on Si(100). Direct evidence of Pt short-circuit diffusion via grain boundaries, Harrison’s type-B regime, is found after silicidation to form (Ni0.99Pt0.01)Si. This underscores the importance of interfacial phenomena for stabilizing this low-resistivity phase, providing insights into the modification of NiSi texture, grain size, and morphology caused by Pt. Platinum segregates at the (Ni0.99Pt0.01)Si/Si(100) interface, which may be responsible for the increased resistance of (Ni0.99Pt0.01)Si to agglomeration. The relative shift in work function between as-deposited and annealed states is greater for Ni(Pt)Si than for NiSi.
Localized modes in capped single-walled carbon nanotubes
Authors: Savin Alexander V. , Kivshar Yuri S.
Published: March 2009

We study numerically small-amplitude oscillations in capped single-walled carbon nanotubes and predict the existence of surface modes localized at capped tips of the nanotubes. These modes are similar to the surface Tamm states found in solids and optics at the edges of truncated lattices.
Body elimination attitude family resemblance in Kuwait
Authors: Al‐Fayez Ghenaim , Awadalla Abdelwahid , Arikawa Hiroko , Templer Donald I. , Hutton Shane
Published: March 2009

The purpose of the present study was to determine the family resemblance of attitude toward body elimination in Kuwaiti participants. This study was conceptualized in the context of the theories of moral development, importance of cleanliness in the Muslim religion, cross‐cultural differences in personal hygiene practices, previous research reporting an association between family attitudes and body elimination attitude, and health implications. The 24‐item Likert‐type format Body Elimination Attitude Scale—Revised was administered to 277 Kuwaiti high school students and 437 of their parents. Females scored higher, indicating greater disgust, than the males. Moreover, sons' body elimination attitude correlated more strongly with fathers' attitude (r = .85) than with that of the mothers (r = .64). Daughters' attitude was similarly associated with the fathers' (r = .89) and the mothers' attitude (r = .86). The high correlations were discussed within the context of Kuwait having a collectivistic culture with authoritarian parenting style. The higher adolescent correlations, and in particular the boys' correlation with fathers than with mothers, was explained in terms of the more dominant role of the Muslim father in the family. Public health and future research implications were suggested. A theoretical formulation was advanced in which “ideal” body elimination attitude is relative rather than absolute, and is a function of one's life circumstances, one's occupation, one's culture and subculture, and the society that one lives in.
A test of theory of planned behavior in Korea: Participation in alcohol‐related social gatherings
Authors: Park Hee Sun , Lee Dong Wook
Published: March 2009

Two studies are reported using the theory of planned behavior (TPB) to predict and explain joining and not joining alcohol‐related social gatherings among Korean undergraduates in various engineering majors. Specifically, considering that the attitudinal component of TPB is behavioral‐outcome‐based, the current study investigated whether the outcomes of engaging in a behavior and of not engaging in a behavior would similarly predict intentions to engage in a behavior and intentions to not engage in a behavior. The current study also examined whether intentions to engage and intentions to not engage would be significantly related to self‐reported behavior a week later. Participants in Study 1 reported TPB components (attitudes toward behavior, subjective norms, perceived behavioral control, and behavioral intentions) concerning joining alcohol‐related social gatherings. Participants in Study 2 reported TPB components concerning not joining alcohol‐related social gatherings. Additionally, a week later, the participants in both studies reported their participation in alcohol‐related social gatherings from the past week. Generally, the results showed that the TPB components were significantly associated with undergraduates' intentions to join and intentions to not join. Specifically, conversation‐related attitudes and senior–junior relationship‐related attitudes were significantly related to intentions to join, and only group‐related attitudes were significantly related to intentions to not join. Intentions to join and intentions to not join were not significantly related to self‐reported behavior of joining alcohol‐related social gatherings a week later. The findings from the current research provide some evidence that joining or not joining alcohol‐related social gatherings may not be mere behavioral opposites, predictable by the presence or absence of the same behavioral outcomes. These two aspects of the behavior may require assessment of different behavioral outcomes or different assessments of the same behavioral outcomes.
Semantic publishing: the coming revolution in scientific journal publishing
Authors: SHOTTON David
Published: March 2009

Recent developments in Web technology can be used for semantic enhancement of scholarly journal articles, by aiding publication of data and metadata and providing ‘lively’ interactive access to content. Such semantic enhancements are already being undertaken by leading STM publishers, and automated text processing will help these enhancements become affordable and routine. Publisher, editor, and author all have primary roles in that process; an incremental approach is needed. Publication of data and metadata to the Web make possible added‐value ‘ecosystem services‘; semantic publishing will bring substantial benefits to scholarly communication.
Scholarly journal information‐seeking and reading patterns of faculty at five US universities
Authors: KING Donald W. , TENOPIR Carol , CHOEMPRAYONG Songphan , WU Lei
Published: March 2009

Surveys at five US universities show that faculty read articles for research, teaching, writing, and other purposes; the largest number of readings is for research. The time spent reading scholarly articles (an estimated average of 132 hours and 240 articles per year) demonstrates their value to faculty's work; over one‐third of readings are reported to be absolutely essential, and to affect the reader's purpose in many ways, including helping to improve results, or to broaden or change the focus. Faculty prefer print for personal subscriptions, although library electronic collections provide a majority of readings, and most readings from library collections are from electronic sources; older articles are also more commonly from electronic library collections. Faculty use a variety of means to find articles, including browsing and searching, the latter particularly for research purposes, and to locate older articles. Faculty members who publish more, or who have won awards, read more articles on average than their less productive or successful colleagues.
Consistent male–male paternity differences across female genotypes
Authors: Sherman Craig D. H , Wapstra Erik , Olsson Mats
Published: March 2009

In a recent paper, we demonstrated that male–female genetic relatedness determines male probability of paternity in experimental sperm competition in the Peron's tree frog (
Litoria peronii
), with a more closely related male outcompeting his rival. Here, we test the hypothesis that a male–male difference in siring success with one female significantly predicts the corresponding difference in siring success with another female. With male sperm concentration held constant, and the proportion of viable sperm controlled statistically, the male–male difference in siring success with one female strongly predicted the corresponding difference in siring success with another female, and alone explained more than 62 per cent of the variance in male–male siring differences. This study demonstrates that male siring success is primarily dictated by among-male differences in innate siring success with less influence of male–female relatedness.
The demography of range boundaries versus range cores in eastern US tree species
Authors: Purves Drew W
Published: March 2009

Regional species–climate correlations are well documented, but little is known about the ecological processes responsible for generating these patterns. Using the data from over 690 000 individual trees I estimated five demographic rates—canopy growth, understorey growth, canopy lifespan, understorey lifespan and per capita reproduction—for 19 common eastern US tree species, within the core and the northern and southern boundaries, of the species range. Most species showed statistically significant boundary versus core differences in most rates at both boundary types. Differences in canopy and understorey growth were relatively small in magnitude but consistent among species, being lower at the northern (average −17%) and higher at the southern (average +12%) boundaries. Differences in lifespan were larger in magnitude but highly variable among species, except for a marked trend for reduced canopy lifespan at the northern boundary (average −49%). Differences in per capita reproduction were large and statistically significant for some species, but highly variable among species. The rate estimates were combined to calculate two performance indices:R0(a measure of lifetime fitness in the absence of competition) was consistently lower at the northern boundary (average −86%) whereasZ*(a measure of competitive ability in closed forest) showed no sign of a consistent boundary–core difference at either boundary.
The effect of sterilizing diseases on host abundance and distribution along environmental gradients
Authors: Antonovics Janis
Published: March 2009

This study analyses the effect of host-specific pathogens on range restriction of their hosts across environmental gradients at population margins. Sterilizing diseases can limit host range by causing large reductions in population size in what would otherwise be the central area of a species range. Diseases showing frequency-dependent transmission can also pull back a population from its disease-free margin. A wide range of disease prevalence versus abundance patterns emerge which often differ from the classical expectation of increasing prevalence with increasing abundance. Surprisingly, very few empirical studies have investigated the dynamics of disease across environmental gradients or at range limits.
Testing evolutionary hypotheses about species borders: patterns of genetic variation towards the southern borders of two rainforestDrosophilaand a related habitat generalist
Authors: van Heerwaarden Belinda , Kellermann Vanessa , Schiffer Michele , Blacket Mark , Sgrò Carla M , Hoffmann Ary A
Published: March 2009

Several evolutionary hypotheses help explain why only some species adapt readily to new conditions and expand distributions beyond borders, but there is limited evidence testing these hypotheses. In this study, we consider patterns of neutral (microsatellite) and quantitative genetic variation in traits in three species ofDrosophilafrom themontiumspecies group in eastern Australia. We found little support for restricted or asymmetrical gene flow in any species. In rainforest-restrictedDrosophila birchii, there was evidence of selection for increased desiccation and starvation resistance towards the southern border, and a reduction in genetic diversity in desiccation resistance at this border. No such patterns existed forDrosophila bunnanda, which has an even more restricted distribution. In the habitat generalistDrosophila serrata, there was evidence for geographic selection for wing size and development time, although clinal patterns for increased cold and starvation resistance towards the southern border could not be differentiated from neutral expectations. These findings suggest that borders in these species are not limited by low overall genetic variation but instead in two of the species reflect patterns of selection and genetic variability in key traits limiting borders.
Emergence of cooperation in public goods games
Authors: Kurokawa Shun , Ihara Yasuo
Published: March 2009

Evolution of cooperation has been a major issue in evolutionary biology. Cooperation is observed not only in dyadic interactions, but also in social interactions involving more than two individuals. It has been argued that direct reciprocity cannot explain the emergence of cooperation in large groups because the basin of attraction for the ‘cooperative’ equilibrium state shrinks rapidly as the group size increases. However, this argument is based on the analysis of models that consider the deterministic process. More recently, stochastic models of two-player games have been developed and the conditions for natural selection to favour the emergence of cooperation in finite populations have been specified. These conditions have been given as a mathematically simple expression, which is called the one-third law. In this paper, we investigate a stochastic model of
n
-player games and show that natural selection can favour a reciprocator replacing a population of defectors in the
n
-player repeated Prisoner's Dilemma game. We also derive a generalized version of the one-third law (the {2/[
n
(
n
+1)]}

1/(
n
−1)

law). Additionally, contrary to previous studies, the model suggests that the evolution of cooperation in public goods game can be facilitated by larger group size under certain conditions.
Testing limits to adaptation along altitudinal gradients in rainforest
Drosophila
Authors: Bridle Jon R , Gavaz Sedef , Kennington W. Jason
Published: March 2009

Given that evolution can generate rapid and dramatic shifts in the ecological tolerance of a species, what prevents populations adapting to expand into new habitat at the edge of their distributions? Recent population genetic models have focused on the relative costs and benefits of migration between populations. On the one hand, migration may limit adaptive divergence by preventing local populations from matching their local selective optima. On the other hand, migration may also contribute to the genetic variance necessary to allow populations to track these changing optima. Empirical evidence for these contrasting effects of gene flow in natural situations are lacking, largely because it remains difficult to acquire. Here, we develop a way to explore theoretical models by estimating genetic divergence in traits that confer stress resistance along similar ecological gradients in rainforest
Drosophila
. This approach allows testing for the coupling of clinal divergence with local density, and the effects of genetic variance and the rate of change of the optimum on the response to selection. In support of a swamping effect of migration on phenotypic divergence, our data show no evidence for a cline in stress-related traits where the altitudinal gradient is steep, but significant clinal divergence where it is shallow. However, where clinal divergence is detected, sites showing trait means closer to the presumed local optimum have more genetic variation than sites with trait means distant from their local optimum. This pattern suggests that gene flow also aids a sustained response to selection.
Mode of transmission and the evolution of arbovirus virulence in mosquito vectors
Authors: Lambrechts Louis , Scott Thomas W
Published: March 2009

The traditional assumption that vector-borne pathogens should evolve towards a benign relationship with their arthropod vectors has been challenged on theoretical grounds and empirical evidence. However, in the case of arboviruses (arthropod-borne viruses), although a number of investigators have reported experimental evidence for virus-induced vector mortality, others have failed to detect any significant impact. Whether this variation in the observed level of arbovirus virulence depends on biological traits or experimental design is unclear. Here, we perform a meta-analysis of studies across a range of mosquito–virus systems to show that, overall, arboviruses do reduce the survival of their mosquito vectors, but that the magnitude of the effect depends on the vector/virus taxonomic groups and the mode of virus transmission. Alphaviruses were associated with highest virulence levels in mosquitoes. Horizontal transmission (intrathoracic inoculation or oral infection) was correlated with significant virus-induced mortality, whereas a lack of adverse effect was found forAedesmosquitoes infected transovarially by bunyaviruses—a group of viruses characterized by high natural rates of vertical transmission in their enzootic vectors. Our findings are consistent with the general prediction that vertically transmitted pathogens should be less virulent than those transmitted horizontally. We conclude that varying degrees of virulence observed among vector–virus systems probably reflect different selective pressures imposed on arboviruses that are primarily transmitted horizontally versus vertically.
The evolution of judgement bias in indirect reciprocity
Authors: Rankin Daniel J , Eggimann Franziska
Published: March 2009

Indirect reciprocity is a form of reciprocity where help is given to individuals based on their reputation. In indirect reciprocity, bad acts (such as not helping) reduce an individual's reputation while good acts (such as helping) increase an individual's reputation. Studies of indirect reciprocity assume that good acts and bad acts are weighted equally when assessing the reputation of an individual. As different information can be processed in different ways, this is not likely to be the case, and it is possible that an individual could bias an actor's reputation by putting more weight to acts of defection (not helping) than acts of co-operation (helping) or
vice versa
. We term this difference ‘judgement bias’, and build an individual-based model of image scoring to investigate the conditions under which it may evolve. We find that, if the benefits of co-operation are small, judgement bias is weighted towards acts perceived to be bad; if the benefits are high, the reverse is true. Our result is consistent under both scoring and standing strategies, and we find that allowing judgement bias to evolve increases the level of co-operation in the population.
A sphenodontine (Rhynchocephalia) from the Miocene of New Zealand and palaeobiogeography of the tuatara (
Sphenodon
)
Authors: Jones Marc E.H , Tennyson Alan J.D , Worthy Jennifer P , Evans Susan E , Worthy Trevor H
Published: March 2009

Jaws and dentition closely resembling those of the extant tuatara (
Sphenodon
) are described from the Manuherikia Group (Early Miocene; 19–16 million years ago, Mya) of Central Otago, New Zealand. This material is significant in bridging a gap of nearly 70 million years in the rhynchocephalian fossil record between the Late Pleistocene of New Zealand and the Late Cretaceous of Argentina. It provides the first pre-Pleistocene record of Rhynchocephalia in New Zealand, a finding consistent with the view that the ancestors of
Sphenodon
have been on the landmass since it separated from the rest of Gondwana 82–60 Mya. However, if New Zealand was completely submerged near the Oligo-Miocene boundary (25–22 Mya), as recently suggested, an ancestral sphenodontine would need to have colonized the re-emergent landmass
via
ocean rafting from a currently unrecorded and now extinct Miocene population. Although an Early Miocene record does not preclude that possibility, it substantially reduces the temporal window of opportunity. Irrespective of pre-Miocene biogeographic history, this material also provides the first direct evidence that the ancestors of the tuatara, an animal often perceived as unsophisticated, survived in New Zealand despite substantial local climatic and environmental changes.
Methylation of estrogen receptor 1 in colorectal adenomas is not age‐dependent, but is correlated with K‐ras mutation
Authors: Horii Joichiro , Hiraoka Sakiko , Kato Jun , Saito Shunsuke , Harada Keita , Fujita Hideyuki , Kaji Eisuke , Yamamoto Kazuhide
Published: March 2009

The promoter region of estrogen receptor 1 (ESR1) has been shown to be methylated in normal colorectal mucosa in an age‐dependent manner. However, the methylation of this region in colorectal tumors has not sufficiently been investigated. The methylation status of ESR1 in 105 colorectal adenoma tissues was examined by MethyLight and presented as the percentage of methylated references (PMR). Factors that affect the PMR of ESR1 in adenomas were determined using parameters including patient age, sex, past history of malignancy, family history of colorectal cancer, smoking and drinking habits, clinical characteristics of adenomas (location, size, macroscopic appearance, and histology), and K‐ras mutation. Multiple linear regression revealed that the PMR was not correlated with patient age. K‐ras mutation was significantly correlated with the higher methylation status of ESR1 in adenoma (t‐value = 3.21, P = 0.0018), whereas alcohol exposure was significantly correlated with lower methylation status (t‐value = –2.37, P = 0.02). Because methylation of O6‐methylguanine DNA methyltransferase (MGMT) has been reported to be correlated with K‐ras G‐to‐A transition, methylation of ESR1 was compared with that of MGMT with regard to K‐ras mutation. Contrary to expectations, methylation of MGMT was not significantly correlated with K‐ras G‐to‐A transition, but that of ESR1 was strongly correlated with K‐ras G‐to‐A transition. Thus, the methylation status of ESR1 in adenomas was not correlated with patient age, but was associated with K‐ras mutation, suggesting that methylation of ESR1 in tumors functions differently from that in normal colon mucosa. (Cancer Sci 2009; 100: 1005–1011)
Shear stress induces internalization of E‐cadherin and invasiveness in metastatic oesophageal cancer cells by a Src‐dependent pathway
Authors: Lawler Karen , O'Sullivan Gerald , Long Aideen , Kenny Dermot
Published: March 2009

Metastatic disease is dependent on tumor cell migration through the venous and lymphatic systems and requires dynamic rearrangement of adherens junctions. Endocytosis of cadherins is a key mechanism to dynamically arrange adherens junctions, signaling, and motility in tumor cells; however, the role of shear in regulating this process in metastatic cells is unknown. In this study, the role of shear in regulating cell surface expression of E‐cadherin was investigated. We found that exposure to venous shear (shear rate, 200/s) induced internalization of E‐cadherin in adherent metastatic oesophageal tumor cells (OC‐1 tumor cell line). Internalized E‐cadherin was found localized to Rab5‐positive endosomes and was not present in lysosomes. As the Src family of tyrosine kinase have been implicated in regulating cadherin expression, we investigated the role of shear in regulating E‐cadherin through Src activity. Pretreatment of OC‐1 cells with the specific Src kinase inhibitor 4‐amino‐5‐ (4‐methylphenyl)‐7‐(t‐butyl)pyrazolo[3,4‐d]pyrimidine (PP1) prevented shear‐induced internalization of E‐cadherin. Direct measurement of Src activity (phosphorylation on Y416) showed that Src is activated in sheared OC‐1 cells and that the shear‐induced increase in phospho‐Src is inhibited by the presence of PP1. Moreover, we show that shear stress significantly increased the invasive capacity of OC‐1 cells (P < 0.001), a process inhibited by the presence of PP1. These results indicate a novel role for shear in regulating the endocytosis of E‐cadherin and invasiveness in metastatic cells. (Cancer Sci 2009; 100: 1082–1087)
Towards ground truthing exploration in the central Arctic Ocean: a Cenozoic compaction history from the Lomonosov Ridge
Authors: O'Regan M. , Moran K. , Baxter C. D. P. , Cartwright J. , Vogt C. , Kölling M.
Published: March 2009

The Integrated Ocean Drilling Program's Expedition 302, the Arctic Coring Expedition (ACEX), recovered the first Cenozoic sedimentary sequence from the central Arctic Ocean. ACEX provided ground truth for basin scale geophysical interpretations and for guiding future exploration targets in this largely unexplored ocean basin. Here, we present results from a series of consolidation tests used to characterize sediment compressibility and permeability and integrate these with high‐resolution measurements of bulk density, porosity and shear strength to investigate the stress history and the nature of prominent lithostratigraphic and seismostratigraphic boundaries in the ACEX record. Despite moderate sedimentation rates (10–30 m Myr−1) and high permeability values (10−15–10−18 m2), consolidation and shear strength measurements both suggest an overall state of underconsolidation or overpressure. One‐dimensional compaction modelling shows that to maintain such excess pore pressures, an in situ fluid source is required that exceeds the rate of fluid expulsion generated by mechanical compaction alone. Geochemical and sedimentological evidence is presented that identifies the Opal A–C/T transformation of biosiliceous rich sediments as a potential additional in situ fluid source. However, the combined rate of chemical and mechanical compaction remain too low to fully account for the observed pore pressure gradients, implying an additional diagenetic fluid source from within or below the recovered Cenozoic sediments from ACEX. Recognition of the Opal A–C/T reaction front in the ACEX record has broad reaching regional implications on slope stability and subsurface pressure evolution, and provides an important consideration for interpreting and correlating the spatially limited seismic data from the Arctic Ocean.
Effects of a mandibular advancement device on the upper airway morphology: a cephalometric analysis
Authors: DOFF M. H. J. , HOEKEMA A. , PRUIM G. J. , Van Der HOEVEN J. H. , De BONT L. G. M. , STEGENGA B.
Published: March 2009

Summary  The aims of this study were to assess changes in the upper airway morphology associated with an oral appliance in situ in patients suffering from the obstructive sleep apnoea–hypopnoea syndrome and to relate these changes to treatment response. Changes in upper airway morphology as a result of an oral appliance were assessed in 52 patients with obstructive sleep apnoea–hypopnoea syndrome by means of cephalometric analysis. Lateral cephalograms were taken at baseline and after 2–3 months of treatment. Baseline and follow‐up cephalograms were traced twice and cephalometric variables were compared. The predictive value of changes in upper airway morphology for the treatment response was evaluated in univariate and multivariate regression analyses. Oral appliance therapy resulted in an increased posterior airway space at the level of the second vertebra, the uvular tip and the base of the tongue. The increase of the posterior airway space at the level of the second vertebra and the uvular tip were the best predictors for relative improvement of the apnoea–hypopnoea index. However, the predictive value for treatment response of these cephalometric upper airway changes should be interpreted with caution.
Drugs and blood transfusions: dogma‐ or evidence‐based practice?
Authors: Murdock J. , Watson D. , Dorée C. J. , Blest A. , Roberts M. M. , Brunskill S. J.
Published: March 2009

summary There is a lack of consensus on the safety of the coadministration of drugs and red blood cells (RBCs). A systematic review was undertaken to establish the evidence base for this question and assess how the evidence may be translated into present clinical day practice. Comprehensive searches of MEDLINE, EMBASE, CINAHL, the Cochrane Library and hand searching of transfusion journals, guidelines and websites identified 12 relevant papers: 11 in‐vitro experiments and 1 case report. Data on incidences of haemolysis and agglutination following coadministration were extracted and analysed. Overall findings suggest that iron chelators (two papers), antimicrobials (three papers) and lower doses of opioids (three papers) are safe to coadminister with RBCs. Haemolysis was observed with higher doses of opioids (three papers). Transposition of these findings to clinical practice is limited because of the lack of clinical applicability of in‐vitro experiments and diversity in how, and what, clinical outcome measures were used. Further evidence from true clinical settings would be required to inform clinical practice on the efficacy and safety of the coadministration of drugs and RBCs.
Towards better blood transfusion – recruitment and training
Authors: Hill Q. A. , Hill A. , Allard S. , Murphy M. F.
Published: March 2009

summary Recent national initiatives in blood transfusion safety in the UK have created the need for an expansion in haematologists subspecializing (wholly or in part) in transfusion medicine. In 2008, there are 62 transfusion consultants in the UK, but only 42 are full time, and only 19 have hospital sessions. Despite the need for expansion, recruitment appears difficult. The English blood transfusion service, National Health Service Blood and Transplant (NHSBT), is undergoing major reconfiguration, and the current practice of transfusion training for haematology specialists primarily at blood centres with little or no hospital training is not sustainable or desirable. Delivering a high‐quality transfusion programme to haematology trainees is best achieved through an increased emphasis on hospital‐based training. Improved research opportunities, joint NHSBT/hospital posts and a separate subspecialty training curriculum may stimulate interest in transfusion medicine.
Association of Filaggrin loss‐of‐function‐mutations with atopic dermatitis and asthma in the Early Treatment of the Atopic Child (ETAC) population
Authors: Müller Sebastian , Marenholz Ingo , Lee Young‐Ae , Sengler Claudia , Zitnik Simona Eva , Griffioen Rupino W. , Meglio Paolo , Wahn Ulrich , Nickel Renate
Published: March 2009

Many candidate gene studies for atopic dermatitis (AD) and associated phenotypes have been conducted so far, but replication of significant results has been a major problem. Two loss of function polymorphisms FLG R501X‐ and 2282del4, in the Filaggrin (FLG) gene encoding for an epidermal barrier protein were recently identified. They were reported to be predisposing factors for AD and concomitant asthma. Several groups confirmed the initial results in independent populations. The aim of this study is to further investigate the importance of these FLG variants in the development of AD and subsequent asthma symptoms in pre‐school children, we investigated children and parents of the Early Treatment of the Atopic Child (ETAC)‐trial. We genotyped 496 children and 488 parents of the ETAC population for the two FLG variants, evaluating an association by family based analysis (transmission disequilibrium test). We found a highly significant association of the FLG null variants R501X‐ and 2282del4 with AD (combined genotype p < 0.0001) and asthma (combined genotype p < 0.0001). The replication and its statistical significance underlines the importance of the FLG polymorphisms and the importance of the skin barrier function in the development of AD and subsequent asthma.
A case of disseminated histoplasmosis following autologous stem cell transplantation for Hodgkin's lymphoma: an initial misdiagnosis with a false‐positive serum galactomannan assay
Authors: Jones O. , Cleveland K.O. , Gelfand M.S.
Published: March 2009

Abstract: Systemic histoplasmosis is uncommonly reported in patients who have undergone bone marrow or solid organ transplantation. Diagnosis of systemic histoplasmosis in recipients of transplants may be hampered by lack of consideration of this infection in the differential diagnosis and may be confounded by conflicting information from other testing performed to evaluate for opportunistic infections in this population. We report successful treatment of a case of disseminated histoplasmosis in a patient with Hodgkin's lymphoma who had undergone autologous stem cell transplantation. The diagnosis was delayed by the finding of a positive serum galactomannan assay.
Mycophenolic acid inhibits PMA‐induced activation of the neutrophil respiratory burst
Authors: Jüttner B. , Bencel M. , Weißig A. , Studzinski A. , Stenger K. , Scheinichen D.
Published: March 2009

Abstract: Mycophenolate mofetil (MMF) is commonly used in immunosuppressive regimens for solid organ transplantation. There is evidence that the hydrolyzed active agent mycophenolic acid (MPA) causes the endothelial depletion of intracellular guanosine 5′‐triphosphate (GTP) levels. This depletion may cause inactivation of nicotinamide adenine dinucleotide phosphate oxidase. The purpose of the present study was to examine the impact of MPA on the neutrophil respiratory burst and phagocytic activity using flow cytometry. In whole blood of healthy volunteers, 2 different doses of MPA (1 and 10 μmol/L) did not alter hydrogen peroxide production of neutrophils induced by receptor‐dependent activators. In contrast, MPA inhibits the protein kinase C (PKC)‐mediated hydrogen peroxide production by phorbol 12‐myristate 13‐acetate (PMA) in a time‐dependent manner (negative: 21.17 ± 1.64 vs. 120 min: 14.46 ± 1.28 mean fluorescence intensity, incubation with 1 μmol/L MPA). In conclusion, our results corroborated that the neutrophil respiratory burst activity of healthy volunteers, induced by either formyl‐methionyl‐leucylphenylalanine (fMLP), priming with tumor necrosis factor alpha followed by fMLP or Escherichia coli and neutrophil phagocytic capacity, were not significantly affected after MPA treatment. We also could demonstrate that the hydrogen peroxide production of neutrophils decreased in response to the PKC activator PMA in a time‐dependent manner.
Searching for DNA markers for milk production and composition on chromosome 6 in sheep
Authors: Árnyasi M. , Komlósi I. , Lien S. , Czeglédi L. , Nagy S. , Jávor A.
Published: March 2009

Several milk protein polymorphisms are potential tools for selection in dairy ruminants. However, research results for dairy sheep are not as conclusive as those for goats or cattle and are often controversial. The main objective of this study was to find and later use molecular genetic markers in selection to improve milk production and milk composition in Awassi ewes. Chromosome 6 was chosen because several studies have reported the presence of significant quantitative trait loci (QTL) affecting milk production traits on ovine and bovine chromosome 6. Altogether, genotypes for 13 microsatellite loci were determined for 258 ewes, which were purebred Awassi or Awassi‐Merino crosses. Phenotypic data were lactation yield of milk, milk fat, protein and lactose (kg), average milk protein and fat percentage and average somatic cell count. Five out of the 13 microsatellites showed significant association with at least one of the examined traits.
Transitional credit modelling and its relationship to market value at risk: an Australian sectoral perspective
Authors: Allen David E. , Powell Robert
Published: March 2009

Internal credit risk modelling is important for banks for the calculation of capital adequacy in terms of the Basel Accords, and for the management of sectoral exposure. We examine Credit Value at Risk (VaR), Conditional Credit Value at Risk (Credit CVaR) and the relationship between market and credit risk. Significant association is found between different Credit CVaR methods, and between market and credit risk. Simpler Credit CVaR methods are found to be viable alternatives to more complex methodology. The relationship between market and credit risk is used to develop a new model that allows banks to incorporate industry risk into transition modelling, without macroeconomic analysis.
Leveraged superannuation
Authors: Dunn Peter , Francis Scott , Hall Jason
Published: March 2009

Rules governing superannuation investments are made with respect to investment‐specific risks, rather than overall portfolio risks. In particular, legislation prohibits borrowing except in specific circumstances and on a non‐recourse basis. We model the distribution of leveraged portfolio outcomes for a representative investor, accounting for their age‐earnings profile, differing taxation of dividends, capital gains and franking credits, and the volatility of equity returns and interest rates. With explicit portfolio modelling, there is no need to categorize specific investments as ‘too risky’ on a stand‐alone basis. We show that leverage is likely to enhance retirement outcomes for investors with low risk aversion.
Developmental “Roots” in Mature Biological Knowledge
Authors: Goldberg Robert F. , Thompson-Schill Sharon L.
Published: March 2009

Young children tend to claim that moving artifacts and nonliving natural kinds are alive, but neglect to ascribe life to plants. This research tested whether adults exhibit similar confusions when verifying life status in a speeded classification task. Experiment 1 showed that undergraduates encounter greater difficulty (reduced accuracy and increased response times) in determining life status for plants, relative to animals, and for natural and moving nonliving things, relative to artifacts and nonmoving things. Experiment 2 replicated these effects in university biology professors. The professors showed a significantly reduced effect size for living things, as compared with the students, but still showed greater difficulty for plants than animals, even as no differences from the students were apparent in their responses to nonliving things. These results suggest that mature biological knowledge relies on a developmental foundation that is not radically overwritten or erased with the profound conceptual changes that accompany mastery of the domain.
Gaze-Triggered Orienting as a Tool of the Belongingness Self-Regulation System
Authors: Wilkowski Benjamin M. , Robinson Michael D. , Friesen Chris Kelland
Published: March 2009

Social-psychological theories of belongingness self-regulation suggest that when one's need for interpersonal relationships is not being met, one begins to monitor the social environment more closely. Presumably, this serves to increase awareness of the likelihood of social acceptance versus rejection and to inform later social decision-making processes. The current investigation tested whether low belongingness increases a particular form of social monitoring that has recently been documented in the cognitive literature: gaze-triggered orienting. Low belongingness was operationalized either in terms of low trait self-esteem (Studies 1a and 1b) or in terms of the priming of rejection-related thoughts ( Study 2 ). Across the studies, the normal tendency to orient attention in accordance with another individual's eye gaze was augmented under conditions of low belongingness. However, belongingness had no influence on a nonsocial form of orienting. The results are discussed in terms of their implications for theories of belongingness self-regulation and social attention.
Phonetics and phonology in Gallo‐Romance palatalisation
Authors: Buckley Eugene
Published: March 2009

Palatalisation of the velars /k, in Gallo‐Romance applied not just before the usual front vowels /i, e, ɛ/ but also, famously, before the low vowel /a/. Various scenarios have been proposed regarding the phonetic realisation of /a/ and its relation to palatalisation. I argue that /a/ was allophonically fronted to [æ] in stressed open syllables, where the vowel eventually merged with /ɛ, e/. Here the palatalisation was phonetically motivated. But due to the relationship of fronted [æ] to the phonemic category /a/, the triggering environment was extended to other tokens of /a/, including non‐fronted instances in closed syllables. Here the motivation was the abstract phonological connection between the different surface realisations of /a/.
Bootstrap prediction intervals in state–space models
Authors: Rodriguez Alejandro , Ruiz Esther
Published: March 2009

Abstract.  Prediction intervals in state–space models can be obtained by assuming Gaussian innovations and using the prediction equations of the Kalman filter, with the true parameters substituted by consistent estimates. This approach has two limitations. First, it does not incorporate the uncertainty caused by parameter estimation. Second, the Gaussianity of future innovations assumption may be inaccurate. To overcome these drawbacks, Wall and Stoffer [Journal of Time Series Analysis (2002) Vol. 23, pp. 733–751] propose a bootstrap procedure for evaluating conditional forecast errors that requires the backward representation of the model. Obtaining this representation increases the complexity of the procedure and limits its implementation to models for which it exists. In this article, we propose a bootstrap procedure for constructing prediction intervals directly for the observations, which does not need the backward representation of the model. Consequently, its application is much simpler, without losing the good behaviour of bootstrap prediction intervals. We study its finite‐sample properties and compare them with those of the standard and the Wall and Stoffer procedures for the local level model. Finally, we illustrate the results by implementing the new procedure to obtain prediction intervals for future values of a real time series.
A parametric estimation method for dynamic factor models of large dimensions
Authors: Kapetanios George , Marcellino Massimiliano
Published: March 2009

Abstract.  The estimation of dynamic factor models for large sets of variables has attracted considerable attention recently, because of the increased availability of large data sets. In this article we propose a new parametric methodology for estimating factors from large data sets based on state–space models and discuss its theoretical properties. In particular, we show that it is possible to estimate consistently the factor space. We also conduct a set of simulation experiments that show that our approach compares well with existing alternatives.
Neuromedin U: physiology, pharmacology and therapeutic potential
Authors: Budhiraja S. , Chugh A.
Published: March 2009

Neuromedin U (NmU), a multifunctional neuropeptide, belongs to a family of neuropeptides, the neuromedins. It is ubiquitously distributed with highest levels found in the gastrointestinal tract and pituitary. The conservation of structural elements of NmU across species, the widespread distribution of NmU and its receptors throughout the body point to a fundamental role in key physiological processes. Two G protein coupled receptors for NmU have been cloned NmU R1 and NmU R2. NmU R1 is expressed pre‐dominantly in the periphery especially the gastrointestinal tract whereas NmU R2 is expressed pre‐dominantly in the central nervous system. Current evidence suggests a role of NmU in pain, in regulation of feeding and energy homeostasis, stress, cancer, immune mediated inflammatory diseases like asthma, inflammatory diseases, maintaining the biological clock, in the regulation of smooth muscle contraction in the gastrointestinal and genitourinary tract, and in the control of blood flow and blood pressure. With the development of drugs selectively acting on receptors and knockout animal models, exact pathophysiological roles of NmU will become clearer.