bluuebunny/crossref_metadata_2025 huggingface dataset:
Left handed dispersion of a stack of subwavelength hole metal arrays at terahertz frequencies
Authors: Croënne Charles , Garet Frédéric , Lheurette Éric , Coutaz Jean-Louis , Lippens Didier
Published: April 2009

We report on the electromagnetic response of a stack of subwavelength hole metal arrays. The samples were designed for exhibiting left handed dispersion branches under normal incidence, and their transmissivities were optimized via the fabrication of elliptical-shaped holes. They are constituted of benzocyclobutene layers with tens of micron thicknesses and submicron-thick gold films patterned by photolithography. Experimental evidence, achieved by time-domain terahertz spectroscopy and supported by full wave simulations, of a ground left handed dispersion branch is found around 0.45 THz. The insertion losses are −3 dB for a five-layer structure, this good level being explained by the matching of the impedance.
Microstrip superconducting quantum interference device radio-frequency amplifier: Effects of negative feedback on input impedance
Authors: Mück M. , Hover D. , Sendelbach S. , McDermott R.
Published: April 2009

We present the results of measurements of the scattering parameters of microstrip amplifiers (MSAs) based on the dc superconducting quantum interference device. The amplifier input impedance is poorly matched to typical transmission line impedances, resulting in high input return loss around −2 dB. We show that negative feedback can lower the MSA input impedance to achieve a robust match to 50 Ω. In the presence of capacitive and inductive feedback, the input return loss of the MSA can be reduced below −10 dB, opening the door to the practical use of the MSA for a variety of demanding applications.
Relative importance of fuel management, ignition management and weather for area burned: evidence from five landscape - fire - succession models
Authors: Cary Geoffrey J. , Flannigan Mike D. , Keane Robert E. , Bradstock Ross A. , Davies Ian D. , Lenihan James M. , Li Chao , Logan Kimberley A. , Parsons Russell A.
Published: April 2009

The behaviour of five landscape fire models (CAFÉ, FIRESCAPE, LAMOS(HS), LANDSUM and SEM-LAND) was compared in a standardised modelling experiment. The importance of fuel management approach, fuel management effort, ignition management effort and weather in determining variation in area burned and number of edge pixels burned (a measure of potential impact on assets adjacent to fire-prone landscapes) was quantified for a standardised modelling landscape. Importance was measured as the proportion of variation in area or edge pixels burned explained by each factor and all interactions among them. Weather and ignition management were consistently more important for explaining variation in area burned than fuel management approach and effort, which were found to be statistically unimportant. For the number of edge pixels burned, weather and ignition management were generally more important than fuel management approach and effort. Increased ignition management effort resulted in decreased area burned in all models and decreased number of edge pixels burned in three models. The findings demonstrate that year-to-year variation in weather and the success of ignition management consistently prevail over the effects of fuel management on area burned in a range of modelled ecosystems.
The melanin-concentrating hormone system modulates cocaine reward
Authors: Chung Shinjae , Hopf F. Woodward , Nagasaki Hiroshi , Li Chun-Ying , Belluzzi James D. , Bonci Antonello , Civelli Olivier
Published: April 2009

Drug addiction is mediated by complex neuronal processes that converge on the shell of the nucleus accumbens (NAcSh). The NAcSh receives inputs from the lateral hypothalamus (LH), where self-stimulation can be induced. Melanin-concentrating hormone (MCH) is produced mainly in the LH, and its receptor (MCH1R) is highly expressed in the NAcSh. We found that, in the NAcSh, MCH1R is coexpressed with dopamine receptors (D1R and D2R), and that MCH increases spike firing when both D1R and D2R are activated. Also, injecting MCH potentiates cocaine-induced hyperactivity in mice. Mice lacking MCH1R exhibit decreased cocaine-induced conditioned place preference, as well as cocaine sensitization. Using a specific MCH1R antagonist, we further show that acute blockade of the MCH system not only reduces cocaine self-administration, but also attenuates cue- and cocaine-induced reinstatement. Thus, the MCH system has an important modulatory role in cocaine reward and reinforcement by potentiating the dopaminergic system in the NAcSh, which may provide a new rationale for treating cocaine addiction.
Childhood poverty, chronic stress, and adult working memory
Authors: Evans Gary W. , Schamberg Michelle A.
Published: March 2009

The income–achievement gap is a formidable societal problem, but little is known about either neurocognitive or biological mechanisms that might account for income-related deficits in academic achievement. We show that childhood poverty is inversely related to working memory in young adults. Furthermore, this prospective relationship is mediated by elevated chronic stress during childhood. Chronic stress is measured by allostatic load, a biological marker of cumulative wear and tear on the body that is caused by the mobilization of multiple physiological systems in response to chronic environmental demands.
Quality of evidence for perceptual decision making is indexed by trial-to-trial variability of the EEG
Authors: Ratcliff Roger , Philiastides Marios G. , Sajda Paul
Published: April 2009

A fundamental feature of how we make decisions is that our responses are variable in the choices we make and the time it takes to make them. This makes it impossible to determine, for a single trial of an experiment, the quality of the evidence on which a decision is based. Even for stimuli from a single experimental condition, it is likely that stimulus and encoding differences lead to differences in the quality of evidence. In the research reported here, with a simple “face”/“car” perceptual discrimination task, we obtained late (decision-related) and early (stimulus-related) single-trial EEG component amplitudes that discriminated between faces and cars within and across conditions. We used the values of these amplitudes to sort the response time and choice within each experimental condition into more-face-like and less-face-like groups and then fit the diffusion model for simple decision making (a well-established model in cognitive psychology) to the data in each group separately. The results show that dividing the data on a trial-by-trial basis by using the late-component amplitude produces differences in the estimates of evidence used in the decision process. However, dividing the data on the basis of the early EEG component amplitude or the times of the peak amplitudes of either component did not index the information used in the decision process. The results we present show that a single-trial EEG neurophysiological measure for nominally identical stimuli can be used to sort behavioral response times and choices into those that index the quality of decision-relevant evidence.
Plastid production of protein antibiotics against pneumonia via a new strategy for high-level expression of antimicrobial proteins
Authors: Oey Melanie , Lohse Marc , Scharff Lars B. , Kreikemeyer Bernd , Bock Ralph
Published: March 2009

Plastid transformation has become an attractive tool in biotechnology. Because of the prokaryotic nature of the plastid's gene expression machinery, expression elements (promoters and untranslated regions) that trigger high-level foreign protein accumulation in plastids usually also confer high expression in bacterial cloning hosts. This can cause problems, for example, when production of antimicrobial compounds is attempted. Their bactericidal activity can make the cloning of the corresponding genes in plastid transformation vectors impossible. Here, we report a general solution to this problem. We have designed a strategy (referred to as toxin shuttle) that allows the expression in plastids of proteins that are toxic to
Escherichia coli
. The strategy is based on blocking transcription in
E. coli
by bacterial transcription terminators upstream of the gene of interest, which subsequently are excised
in planta
by site-specific recombination. We demonstrate the applicability of the strategy by the high-level expression in plastids (to up to 30% of the plant's total soluble protein) of 2 phage-derived protein antibiotics that are toxic to
E. coli
. We also show that the plastid-produced antibiotics efficiently kill pathogenic strains of
Streptococcus pneumoniae
, the causative agent of pneumonia, thus providing a promising strategy for the production of next-generation antibiotics in plants.
Unconventional ligand activation of herpesvirus entry mediator signals cell survival
Authors: Cheung Timothy C. , Steinberg Marcos W. , Oborne Lisa M. , Macauley Matthew G. , Fukuyama Satoshi , Sanjo Hideki , D'Souza Claire , Norris Paula S. , Pfeffer Klaus , Murphy Kenneth M. , Kronenberg Mitchell , Spear Patricia G. , Ware Carl F.
Published: March 2009

The herpesvirus entry mediator (HVEM; TNFRSF14) activates NF-κB through the canonical TNF-related cytokine LIGHT, serving as a costimulatory pathway during activation of T cells. HVEM also functions as a ligand for the Ig superfamily members B and T lymphocyte attenuator (BTLA) and CD160, both of which limit inflammatory responses initiated by T cells. Emerging evidence indicates BTLA also promotes T cell survival, but its structural differences from LIGHT intimate BTLA is unlikely to function as an activator of HVEM. We demonstrate here that BTLA, CD160, and herpes simplex virus envelope glycoprotein D (gD) function as activating ligands for HVEM, promoting NF-κB activation and cell survival. Membrane-expressed BTLA and CD160, as well as soluble dimeric receptor surrogates BTLA-Fc and gD-Fc specifically activated HVEM-dependent NF-κB. BTLA and CD160 engagement induced recruitment of TNF receptor-associated factor 2 (TRAF2), but not TRAF3, to HVEM that specifically activated the RelA but not the RelB form of NF-κB in a mucosal epithelial tumor cell line. Moreover,Btla−/−T cells survived poorly following activation but were rescued with BTLA-Fc, indicating HVEM-BTLA bidirectional signaling may serve as a critical cell-survival system for lymphoid and epithelial cells.
Bilingual and biliteracy practices
Authors: Haneda Mari , Monobe Gumiko
Published: March 2009

In this paper, we report the findings of our qualitative inquiry conducted with two male and two female sojourner students in their early teens living in the United States. Sojourner students, an under-researched population in literacy studies, refers to expatriate children who reside and study abroad for a number of years because of their parents’ jobs and who anticipate eventual return to their home country. Our participants were Japanese sojourner students. Drawing on multiple sources of data, including the students’ literacy logs that documented their reading and writing activities in Japanese and English, interview transcripts, and literacy artifacts, we investigated what kind of literacy practices they engaged in outside school and what developing bilingual and biliterate competences meant to them as individuals. Our findings indicate that (a) although the four students spent much time on academic literacy in Japanese and English outside school, they also had active literate lives of their own; and (b) gender affected not only how they perceived their competencies in the two languages but also how they allocated their time outside school to engage in literacy practices in each language. While there is little investigation of this student population from the perspective of gender, we suggest that it is an important issue to take into account in future research.
A Multisite Randomized Trial of Social Norms Marketing Campaigns to Reduce College Student Drinking: A Replication Failure
Authors: DeJong William , Schneider Shari Kessel , Towvim Laura Gomberg , Murphy Melissa J. , Doerr Emily E. , Simonsen Neal R. , Mason Karen E. , Scribner Richard A.
Published: April 2009

A 14-site randomized trial tested the effectiveness of social norms marketing (SNM) campaigns, which present accurate student survey data in order to correct misperceptions of subjective drinking norms and thereby drive down alcohol use. Cross-sectional student surveys were conducted by mail at baseline and at posttest 3 years later. Hierarchical linear modeling was applied to examine multiple drinking outcomes, taking into account the nonindependence of students grouped in the same college. Controlling for other predictors, having a SNM campaign was not significantly associated with lower perceptions of student drinking levels or lower self-reported alcohol consumption. This study failed to replicate a previous multisite randomized trial of SNM campaigns, which showed that students attending institutions with a SNM campaign had a lower relative risk of alcohol consumption than students attending control group institutions (W. DeJong et al. J Stud Alcohol. 2006;67:868–879). Additional research is needed to explore whether SNM campaigns are less effective in campus communities with relatively high alcohol retail outlet density.
Efficacy of a Brief Intervention to Improve Emergency Physicians’ Smoking Cessation Counseling Skills, Knowledge, and Attitudes
Authors: Bernstein Steven L. , Boudreaux Edwin D. , Cabral Lisa , Cydulka Rita K. , Schwegman David , Larkin Gregory L. , Adams Annette L. , McCullough Lynne B. , Rhodes Karin V.
Published: April 2009

The objective of this study was to test whether a brief educational/administrative intervention could increase tobacco counseling by emergency physicians (EPs). Pre-/post-study at eight emergency departments (EDs) with residency programs were carried out. EPs received a 1-hour lecture on the health effects of smoking and strategies to counsel patients. After the lecture, cards promoting a national smokers’ quitline were placed in EDs, to be distributed by providers. Providers completed pre-/ post-intervention questionnaires. Patients were interviewed pre-/post-intervention to assess provider behavior. Two hundred eighty-seven EPs were enrolled. Post-intervention, providers were more likely to consider tobacco counseling part of their role, and felt more confident in counseling. Data from 1168 patient interviews and chart reviews showed that, post-intervention, providers were more likely to ask patients about smoking, make a referral, and document smoking counseling. Post-intervention, 30% of smokers were given a Quitline referral card. An educational intervention improved ED-based tobacco interventions. Controlled trials are needed to establish these results’ durability.
Humanoid Robot RH‐1 for Collaborative Tasks: A Control Architecture for Human‐Robot Cooperation
Authors: Monje Concepción A. , Pierro Paolo , Balaguer Carlos
Published: April 2009

The full‐scale humanoid robot RH‐1 has been totally developed in the University Carlos III of Madrid. In this paper we present an advanced control system for this robot so that it can perform tasks in cooperation with humans. The collaborative tasks are carried out in a semi‐autonomous way and are intended to be put into operation in real working environments where humans and robots should share the same space. Before presenting the control strategy, the kinematic model and a simplified dynamic model of the robot are presented. All the models and algorithms are verified by several simulations and experimental results.
Analysis of Physical Human–Robot Interaction for Motor Learning with Physical Help
Authors: Ikemoto Shuhei , Minato Takashi , Ishiguro Hiroshi
Published: April 2009

In this paper, we investigate physical human–robot interaction (PHRI) as an important extension of traditional HRI research. The aim of this research is to develop a motor learning system that uses physical help from a human helper. We first propose a new control system that takes advantage of inherent joint flexibility. This control system is applied on a new humanoid robot called CB2. In order to clarify the difference between successful and unsuccessful interaction, we conduct an experiment where a human subject has to help the CB2 robot in its rising‐up motion. We then develop a new measure that demonstrates the difference between smooth and non‐smooth physical interactions. An analysis of the experiment’s data, based on the introduced measure, shows significant differences between experts and beginners in human–robot interaction.
Assembly of multiprotein complexes that control genome function
Authors: Dinant Christoffel , Luijsterburg Martijn S. , Höfer Thomas , von Bornstaedt Gesa , Vermeulen Wim , Houtsmuller Adriaan B. , van Driel Roel
Published: April 2009

Live-cell imaging studies aided by mathematical modeling have provided unprecedented insight into assembly mechanisms of multiprotein complexes that control genome function. Such studies have unveiled emerging properties of chromatin-associated systems involved in DNA repair and transcription.
A new model for binding of kinesin 13 to curved microtubule protofilaments
Authors: Mulder Anke M. , Glavis-Bloom Alex , Moores Carolyn A. , Wagenbach Michael , Carragher Bridget , Wordeman Linda , Milligan Ronald A.
Published: April 2009

Kinesin motor proteins use adenosine triphosphate hydrolysis to do work on microtubules (MTs). Most kinesins walk along the MT, but class 13 kinesins instead uniquely recognize MT ends and depolymerize MT protofilaments. We have used electron microscopy (EM) to understand the molecular interactions by which kinesin 13 performs these tasks. Although a construct of only the motor domain of kinesin 13 binds to every heterodimer of a tubulin ring, a construct containing the neck and the motor domain occupies alternate binding sites. Likewise, EM maps of the dimeric full-length (FL) protein exhibit alternate site binding but reveal density for only one of two motor heads. These results indicate that the second head of dimeric kinesin 13 does not have access to adjacent binding sites on the curved protofilament and suggest that the neck alone is sufficient to obstruct access. Additionally, the FL construct promotes increased stacking of rings compared with other constructs. Together, these data suggest a model for kinesin 13 depolymerization in which increased efficiency is achieved by binding of one kinesin 13 molecule to adjacent protofilaments.
Fluorescence changes reveal kinetic steps of muscarinic receptor–mediated modulation of phosphoinositides and Kv7.2/7.3 K+ channels
Authors: Jensen Jill B. , Lyssand John S. , Hague Chris , Hille Bertil
Published: March 2009

G protein–coupled receptors initiate signaling cascades. M1 muscarinic receptor (M1R) activation couples through Gαq to stimulate phospholipase C (PLC), which cleaves phosphatidylinositol 4,5-bisphosphate (PIP2). Depletion of PIP2 closes PIP2-requiring Kv7.2/7.3 potassium channels (M current), thereby increasing neuronal excitability. This modulation of M current is relatively slow (6.4 s to reach within 1/e of the steady-state value). To identify the rate-limiting steps, we investigated the kinetics of each step using pairwise optical interactions likely to represent fluorescence resonance energy transfer for M1R activation, M1R/Gβ interaction, Gαq/Gβ separation, Gαq/PLC interaction, and PIP2 hydrolysis. Electrophysiology was used to monitor channel closure. Time constants for M1R activation (<100 ms) and M1R/Gβ interaction (200 ms) are both fast, suggesting that neither of them is rate limiting during muscarinic suppression of M current. Gαq/Gβ separation and Gαq/PLC interaction have intermediate 1/e times (2.9 and 1.7 s, respectively), and PIP2 hydrolysis (6.7 s) occurs on the timescale of M current suppression. Overexpression of PLC accelerates the rate of M current suppression threefold (to 2.0 s) to become nearly contemporaneous with Gαq/PLC interaction. Evidently, channel release of PIP2 and closure are rapid, and the availability of active PLC limits the rate of M current suppression.
Control of voltage-gated K+ channel permeability to NMDG+ by a residue at the outer pore
Authors: Wang Zhuren , Wong Nathan C. , Cheng Yvonne , Kehl Steven J. , Fedida David
Published: March 2009

Crystal structures of potassium (K+) channels reveal that the selectivity filter, the narrow portion of the pore, is only ∼3-Å wide and buttressed from behind, so that its ability to expand is highly constrained, and the permeation of molecules larger than Rb+ (2.96 Å in diameter) is prevented. N-methyl-d-glucamine (NMDG+), an organic monovalent cation, is thought to be a blocker of Kv channels, as it is much larger (∼7.3 Å in mean diameter) than K+ (2.66 Å in diameter). However, in the absence of K+, significant NMDG+ currents could be recorded from human embryonic kidney cells expressing Kv3.1 or Kv3.2b channels and Kv1.5 R487Y/V, but not wild-type channels. Inward currents were much larger than outward currents due to the presence of intracellular Mg2+ (1 mM), which blocked the outward NMDG+ current, resulting in a strong inward rectification. The NMDG+ current was inhibited by extracellular 4-aminopyridine (5 mM) or tetraethylammonium (10 mM), and largely eliminated in Kv3.2b by an S6 mutation that prevents the channel from opening (P468W) and by a pore helix mutation in Kv1.5 R487Y (W472F) that inactivates the channel at rest. These data indicate that NMDG+ passes through the open ion-conducting pore and suggest a very flexible nature of the selectivity filter itself. 0.3 or 1 mM K+ added to the external NMDG+ solution positively shifted the reversal potential by ∼16 or 31 mV, respectively, giving a permeability ratio for K+ over NMDG+ (PK+/PNMDG+) of ∼240. Reversal potential shifts in mixtures of K+ and NMDG+ are in accordance with PK+/PNMDG+, indicating that the ions compete for permeation and suggesting that NMDG+ passes through the open state. Comparison of the outer pore regions of Kv3 and Kv1.5 channels identified an Arg residue in Kv1.5 that is replaced by a Tyr in Kv3 channels. Substituting R with Y or V allowed Kv1.5 channels to conduct NMDG+, suggesting a regulation by this outer pore residue of Kv channel flexibility and, as a result, permeability.
A Qualitative Exploration of Reasons for Poor Hand Hygiene Among Hospital Workers Lack of Positive Role Models and of Convincing Evidence That Hand Hygiene Prevents Cross-Infection
Authors: Erasmus V. , Brouwer W. , van Beeck E. F. , Oenema A. , Daha T. J. , Richardus J. H. , Vos M. C. , Brug J.
Published: April 2009

Objective.

To study potential determinants of hand hygiene compliance among healthcare workers in the hospital setting.

Design.

A qualitative study based on structured-interview guidelines, consisting of 9 focus group interviews involving 58 persons and 7 individual interviews. Interview transcripts were subjected to content analysis.

Setting.

Intensive care units and surgical departments of 5 hospitals of varying size in the Netherlands.

Participants.

A total of 65 nurses, attending physicians, medical residents, and medical students.

Results.

Nurses and medical students expressed the importance of hand hygiene for preventing of cross-infection among patients and themselves. Physicians expressed the importance of hand hygiene for self-protection, but they perceived that there is a lack of evidence that handwashing is effective in preventing cross-infection. All participants stated that personal beliefs about the efficacy of hand hygiene and examples and norms provided by senior hospital staff are of major importance for hand hygiene compliance. They further reported that hand hygiene is most often performed after tasks that they perceive to be dirty, and personal protection appeared to be more important for compliance that patient safety. Medical students explicitly mentioned that they copy the behavior of their superiors, which often leads to noncompliance during clinical practice. Physicians mentioned that their noncompliance arises from their belief that the evidence supporting the effectiveness of hand hygiene for prevention of hospital-acquired infections is not strong.

Conclusion.

The results indicate that beliefs about the importance of self-protection are the main reasons for performing hand hygiene. A lack of positive role models and social norms may hinder compliance.
A framework for modelling fish and shellfish responses to future climate change
Authors: Hollowed Anne Babcock , Bond Nicholas A. , Wilderbuer Thomas K. , Stockhausen William T. , A'mar Z. Teresa , Beamish Richard J. , Overland James E. , Schirripa Michael J.
Published: April 2009

Hollowed, A. B., Bond, N. A., Wilderbuer, T. K., Stockhausen, W. T., A'mar, Z. T., Beamish, R. J., Overland, J. E., and Schirripa, M. J. 2009. A framework for modelling fish and shellfish responses to future climate change. – ICES Journal of Marine Science, 66: 1584–1594. A framework is outlined for a unified approach to forecasting the implications of climate change on production of marine fish. The framework involves five steps: (i) identification of mechanisms underlying the reproductive success, growth, and distribution of major fish and shellfish populations, (ii) assessment of the feasibility of downscaling implications of climate scenarios derived from Intergovernmental Panel on Climate Change (IPCC) models for regional ecosystems to select and estimate relevant environmental variables, (iii) evaluation of climate model scenarios and select IPCC models that appear to provide valid representations of forcing for the region of study, (iv) extraction of environmental variables from climate scenarios and incorporation into projection models for fish and shellfish, and (v) evaluation of the mean, variance, and trend in fish and shellfish production under a changing ecosystem. This framework was applied to forecast summer sea surface temperature in the Bering Sea from 2001 to 2050. The mean summer surface temperature was predicted to increase by 2°C by 2050. The forecasting framework was also used to estimate the effects of climate change on production of northern rock sole (Lepidopsetta polyxystra) through projected changes in cross-shelf transport of larvae in the Bering Sea. Results suggest that climate change will lead to a modest increase in the production of strong year classes of northern rock sole.
Effects of prey concentration, light regime, and parental origin on growth and survival of herring larvae under controlled experimental conditions
Authors: Folkvord Arild , Høie Hans , Johannessen Arne , Solbakken Turid
Published: April 2009

Folkvord, A., Høie, H., Johannessen, A., and Solbakken, T. 2009. Effects of prey concentration, light regime, and parental origin on growth and survival of herring larvae under controlled experimental conditions. – ICES Journal of Marine Science, 66: 1702–1709. Experiments were undertaken to study the combined effects of environmental (prey concentration and photoperiod) and genetic (parental spawning season) factors on growth and survival of herring larvae. During the experimental period, constant prey concentrations were maintained at one of the two nominal levels, under either a spring or an autumn light regime. Eggs of one autumn-spawning North Sea Buchan female herring were fertilized either with cryopreserved sperm from three Norwegian spring-spawning males or with fresh sperm from three Buchan males. Larvae of the two groups (the hybrids marked with alizarin) were mixed in replicated treatment tanks, thus ensuring identical environmental conditions. Mean larval growth rates were mostly influenced by food availability, but the hybrids grew significantly faster than the pure autumn-spawned offspring. In addition, the hybrids experienced a survival advantage at low prey concentrations. Hybrid survival was also somewhat better at high prey concentrations under a spring photoperiod than the corresponding group under an autumn photoperiod, suggesting a possible genetic adaptation to seasonal light conditions. The experiment documents the viability beyond first-feeding of offspring from parents with different spawning periods. The results are discussed in relation to herring metapopulation structure.
Low variation but strong population structure in mitochondrial control region of the plains topminnow, Fundulus sciadicus
Authors: Li C. , Bessert M. L. , Macrander J. , Ortí G.
Published: April 2009

The plains topminnow Fundulus sciadicus is a freshwater killifish endemic to the Great Plains of North America. Rising concerns for future viability of this species have prompted recent changes in its conservation status. In this study, the results of a range‐wide population genetic survey based on the sequence of entire mitochondrial control region (CR) are presented. A total of 181 fish were collected from 11 sites in Nebraska and 10 sites in Missouri spanning the distribution range of the species. Seven polymorphic sites were found in the 966 base pairs of the CR, and only nine unique haplotypes were detected among all fish. Phylogenetic analysis and statistical parsimony networks identified two distinct clades. The first included fish in the Osage, Gasconade and Spring River drainages in Missouri, while the second included individuals from Nebraska and the Lamine River in Missouri, although the Lamine River is much closer to the other Missouri sites than to the Nebraska sites. Pair‐wise FST and average population distances indicated that populations from most drainages are genetically distinct, as 93% of the total molecular variance was attributed to among‐drainage effects. Four sites within the main distributions of this species and a highly disjunct site from the south‐western portion of the range are suggested as potential targets for conservation.
Evidence of two contrasting brown trout Salmo trutta populations spatially separated in the River Borne (France) and shift in management towards conservation of the native lineage
Authors: Caudron A. , Champigneulle A. , Guyomard R.
Published: April 2009

A multidisciplinary study was made of brown trout Salmo trutta in the Borne River, a typical fast‐flowing mountain stream in the Northern French Alps, in the geographical range of the Mediterranean lineages (ML). Information on (1) the proportion of stocked fluoro‐marked fish in the angling harvest, (2) the introgression of introduced DNA microsatellite alleles into the native gene pool and (3) the demography of the population in situ in autumn revealed two contrasting populations separated by a physical barrier to upstream migration. A native S. trutta population (c. 10 000 adults) lives downstream of the barrier and is characterized by a large frequency of ML alleles (82–97%) and high densities (43–55 fish 100 m−2). This population is maintained predominantly by natural recruitment of juveniles (51–82%). In contrast, the upstream population is characterized by a large frequency of Atlantic lineage (AL) alleles (78–100%) and low densities (1–2 fish 100 m−2) and appears to be maintained by restocking (90–100%). The origins of these sharply contrasting populations appear to reflect isolation by an impassable barrier, catastrophic flooding, a downstream gradient in water quality, stocking and fishing pressure. The native downstream population has been resilient to large sudden floods and to intensive stockings of domesticated AL fish. The results of this study justify a shift in management towards conservation and rehabilitation of the native population.
Temporal effective size estimates of a managed walleye Sander vitreus population and implications for genetic‐based management
Authors: Franckowiak R. P. , Sloss B. L. , Bozek M. A. , Newman S. P.
Published: April 2009

The goal of this research was to use the long‐term fishery data set and DNA from archived scales of walleye Sander vitreus in Escanaba Lake, WI, U.S.A., to improve the understanding of the underlying mechanism(s) influencing genetic diversity in naturally recruiting populations. The introduced population of S. vitreus in Escanaba Lake has a low mean effective population size (NE) between 124·6 and 185·5 despite a mean census size (NC) of 4659 (NE/NCc. 0·04), suggesting an accelerated rate of genetic drift between 1952 and 2002. These values are smaller than the median NE range of several studies suggesting typical NE/NC ratios of 0·11–0·16 in a wide range of taxa. NE increased steadily during the past two sampled decades (1992 and 2002) and was consistent with a lowering of the variance in S. vitreus reproductive success, possibly linked to a large, sustained exploitation (mean 28%) rate. Variance in reproductive success is one of the most important factors influencing NE in species, like S. vitreus, which have a potential for large fecundities and large juvenile mortalities (type III survivorship). The NB estimates across six sequential cohorts (age classes of S. vitreus, assayed from 1994 to 1999) was consistent with estimates of NE reported for 1992–2002. These results, coupled with in‐depth census and exploitation data, show that the genetic characteristics of Escanaba Lake S. vitreus have changed substantially and that management activities, such as supplemental stocking and harvest practices, have profoundly influenced the genetic dynamics of S. vitreus in this lake.
Shallow genetic and morphological divergence among seaperches in the South Pacific (family Scorpaenidae; genus Helicolenus)
Authors: Smith P. J. , Struthers C. D. , Paulin C. D. , McVeagh S. M. , Daley R. K.
Published: April 2009

The phylogenetic relationships among populations of seaperch, Helicolenus spp., in the south‐west Pacific were examined with mtDNA markers. Parts of the cytochrome b gene [459 base pair (bp)] and the control region (448 bp) were sequenced in 58 specimens from the south‐west Pacific and four specimens of Helicolenus lengerichi from Chile. Only one clade was recognized in New Zealand coastal waters, despite a wide range of colour morphs. This clade also occurred in the mid Tasman Sea on the Norfolk Ridge and around Tasmania and Victoria. A second sympatric clade was identified around Tasmania and Victoria and to the west of New Zealand. A third allopatric clade was identified to the north of New Zealand and in deep water on the Chatham Rise and a fourth clade on the Foundation Seamounts and the Louisville Ridge. Helicolenus lengerichi from Chile formed a fifth clade. Assuming a molecular clock, the clades were estimated to have diverged c. 0·7–2·6 million years ago. Only two clades, around Tasmania and Victoria, were separated using morphology, colour (in live) and dorsal‐fin soft ray counts and were confirmed as Helicolenus percoides and Helicolenus barathri. Two characters, orbit diameter and colour variation, previously used to identify two species in New Zealand waters were unreliable characters for species discrimination. Principle component analyses of 11 morphological measures from 67 individuals did not delineate the clades. A canonical discriminant analysis was able to separate four of the five clades, but mean discriminate probabilities were low (77·6%), except for the five Chilean specimens of H. lengerichi (100%).
Evaluation of insulin resistance in obese women with and without acanthosis nigricans
Authors: SADEGHIAN Giti , ZIAIE Hengameh , AMINI Masoud , ALI NILFROUSHZADEH Mohhamad
Published: March 2009

Acanthosis nigricans is characterized by hyperpigmented velvety plaques of body folds and neck. Insulin could be a responsible factor in the pathogenesis of this condition and hyperinsulinemia: a consequence of insulin resistance stimulates the formation of these characteristic plaques. In this study, insulin resistance was compared in obese women with and without acanthosis nigricans. This was a cross‐sectional study. Sixty‐six obese women (32 patients with acanthosis nigricans and 34 patients without acanthosis nigricans) were selected randomly. Levels of fasting serum insulin and fasting blood glucose were measured in both groups and insulin resistance was determined using homeostasis model assessment. Glucose tolerance test also was performed for all of participants. Five (15.6%) patients with acanthosis nigricans and no (0%) patient without acanthosis nigricans had insulin resistance (P < 0.05). Six (18.7%) patients with acanthosis nigricans and one (2.9%) patient without acanthosis nigricans had impaired glucose tolerance test (P < 0.05). The mean levels of fasting serum insulin were 15.7 ± 8.7 and 12.2 ± 4.1 µm/mL (P < 0.05) and the mean values of insulin resistance index were 3.5 ± 1.9 and 2.6 ± 0.9 µm/mL between patients with and without acanthosis nigricans, respectively (P < 0.05). In Iranian obese women, acanthosis nigricans is a marker of insulin resistance.
Risks and side‐effects of intrathecal morphine combined with spinal anaesthesia: a meta‐analysis
Authors: Gehling M. , Tryba M.
Published: March 2009

Intrathecal morphine is often used for postoperative analgesia after surgery. We performed a meta‐analysis to obtain more detailed information on the frequency of side‐effects in patients receiving intrathecal morphine in combination with spinal anaesthesia compared with placebo treated patients. We clustered the analysis to patients receiving placebo, less than morphine 0.3 mg (M < 0.3), or equal to or more than morphine 0.3 mg (M ≥ 0.3) and calculated the risk ratios of morphine vs placebo. Twenty‐eight studies investigating 46 morphine groups vs placebo were included. A total of 790 patients with intrathecal morphine and 524 patients who received placebo were analysed. Compared with placebo the lower dose of morphine resulted in an increase of nausea (RR 1.4, 95% CI 1.1–1.7), vomiting (RR 3.1, 95% CI 1.5–6.4) and pruritus (RR 1.8, 95% CI 1.4–2.2). The higher dose resulted in an increased risk ratio for pruritus (RR 5.0, 95% CI 2.9–8.6), but not nausea (RR 1.2, 95% CI 0.9–1.6) or vomiting (RR 1.3, 95% CI 0.9–1.9). Overall, intrathecal morphine did not increase respiratory depression. However, the higher dose of intrathecal morphine was associated with more episodes of respiratory depression (7/80) compared with the lower dose (2/247). Intrathecal morphine is associated with a mild increase in side‐effects. With a dose < 0.3 mg we found there were no more episodes of respiratory depression than in placebo patients who received systemic opioid analgesia.
HIPK2 is involved in cell proliferation and its suppression promotes growth arrest independently of DNA damage
Authors: Iacovelli S. , Ciuffini L. , Lazzari C. , Bracaglia G. , Rinaldo C. , Prodosmo A. , Bartolazzi A. , Sacchi A. , Soddu S.
Published: March 2009

Introduction/objectives:  The serine/threonine kinase homeodomain‐interacting protein kinase 2 (HIPK2) is a co‐regulator of an increasing number of transcription factors and cofactors involved in DNA damage response and development. We and others have cloned HIPK2 as an interactor of the p53 oncosuppressor, and have studied the role of this interaction in cell response to stress. Nevertheless, our original cloning of HIPK2 as a p53‐binding protein, was aimed at discovering partners of p53 involved in cell differentiation and development, still controversial p53 functions. To this aim, we used p53 as bait in yeast two‐hybrid screening of a cDNA library from mouse embryo (day 11 postcoitus) when p53 is highly expressed.

Methods and results: In this study, we directly explored whether HIPK2 and p53 cooperate in cell differentiation. By measuring HIPK2 expression and activity in skeletal muscle and haemopoietic differentiation, we observed inverse behaviour of HIPK2 and p53 – excluding cooperation activity of these two factors in this event. However, by HIPK2 depletion experiments, we showed that drastic HIPK2 suppression promotes cell‐cycle arrest by induction of the cyclin‐dependent kinase inhibitor p21Waf‐1/Cip‐1. HIPK2 activity is independent of DNA damage and takes place in cell‐cycle‐arresting conditions, such as terminal differentiation, growth factor deprivation, and G0 resting.

Conclusions:  HIPK2 was found to be involved in cell‐cycle regulation dependent on p21Waf‐1/Cip‐1 and independent of DNA damage.
Functional stability of stream‐dwelling microbial decomposers exposed to copper and zinc stress
Authors: DUARTE SOFIA , PASCOAL CLÁUDIA , CÁSSIO FERNANDA
Published: March 2009

1. We investigated the resistance of aquatic microbial decomposers to Cu and Zn stress and their ability to recover after release from metal exposure, by examining leaf mass loss, fungal reproduction and microbial biomass and diversity.

2. Alder leaves, colonised in a reference stream, were exposed in microcosms to copper (Cu) or zinc (Zn), alone or in mixtures, with metals added together or sequentially (at day 0 or after 10 days). After 20 days, half of the microcosms were released from metals.

3. Leaf mass loss and fungal reproduction were reduced in most metal treatments, and the structure of fungal and bacterial communities was altered as indicated by identification of conidia and DNA fingerprinting based on denaturing gradient gel electrophoresis. Metals reduced the biomass of bacteria, but not that of fungi.

4. After release from metal stress, the structure of fungal communities became similar to that of control, and a recovery of microbial activity seemed to occur as shown by the lack of differences in leaf mass loss, bacterial biomass and fungal reproduction between control and metal treatments.
Medication errors in an intensive care unit
Authors: Bohomol Elena , Ramos Lais Helena , D’Innocenzo Maria
Published: April 2009

Title.  Medication errors in an intensive care unit.

Aim.  This paper is a report of a study to investigating the incidence types and causes of medication errors (MEs) and the consequences for patients.

Background.  Medication errors are a common problem in hospitals around the world, including those in Brazil.

Method.  An exploratory, quantitative survey design was used and 44 adult inpatients were studied over a 30‐day period in 2006. Three different methods were employed: anonymous self‐reports, staff interviews and review of patient prescriptions.

Findings.  A total of 305 MEs was observed. The mean (sd) number was 6·9 (6·8) per patient. The numbers of MEs per day differed statistically significantly between the two groups with length of stay in the intensive care unit of <1 week and more than 1 week, respectively, with mean (sd) of 0·4 (0·38) vs. 0·73 (0·39) The most frequent types were: omission (71·1%), wrong time of administration (11·5%), and prescribing errors (4·6%). The main causes were: medication not available in the hospital (41%); pharmacy stocking and delivery problems (16·3%); transcription errors (11%). No death was directly related to any ME.

Conclusion.  There is a need to develop a culture of safety and quality in patient care. An understanding of the profile of ME types and frequencies in an institution is fundamental to raise awareness and implement measures to avoid them. Structural and procedural changes in hospital organization, with a focus on the efficacy, efficiency, and effectiveness of the medication system are needed to reduce MEs.
Qualitative case study methodology in nursing research: an integrative review
Authors: Anthony Susan , Jack Susan
Published: April 2009

Title.  Qualitative case study methodology in nursing research: an integrative review.

Aim.  This paper is a report of an integrative review conducted to critically analyse the contemporary use of qualitative case study methodology in nursing research.

Background.  Increasing complexity in health care and increasing use of case study in nursing research support the need for current examination of this methodology.

Data sources.  In 2007, a search for case study research (published 2005–2007) indexed in the CINAHL, MEDLINE, EMBASE, PsychINFO, Sociological Abstracts and SCOPUS databases was conducted. A sample of 42 case study research papers met the inclusion criteria.

Methods.  Whittemore and Knafl’s integrative review method guided the analysis.

Results.  Confusion exists about the name, nature and use of case study. This methodology, including terminology and concepts, is often invisible in qualitative study titles and abstracts. Case study is an exclusive methodology and an adjunct to exploring particular aspects of phenomena under investigation in larger or mixed‐methods studies. A high quality of case study exists in nursing research.

Conclusion.  Judicious selection and diligent application of literature review methods promote the development of nursing science. Case study is becoming entrenched in the nursing research lexicon as a well‐accepted methodology for studying phenomena in health and social care, and its growing use warrants continued appraisal to promote nursing knowledge development. Attention to all case study elements, process and publication is important in promoting authenticity, methodological quality and visibility.
Carers’ and nurses’ appraisals of needs of nursing home placement for frail older in Norway
Authors: Fjelltun Aud‐Mari Sohini , Henriksen Nils , Norberg Astrid , Gilje Fredricka , Normann Hans Ketil
Published: April 2009

Aims and objectives.  The aim of this paper was to explore carers’ and nurses’ appraisals concerning if and when nursing home placement for frail older people awaiting placement was needed and to illuminate ethical issues involved in decisions regarding nursing home placement.

Background.  Requesting nursing home placement can be a complicated decision for carers, causing feelings of failure, anxiety and guilt. After the necessity of nursing home care is determined, the names of the older people are put on waiting lists. While waiting, home health care provides support services. Even with this care, many of the older people and their carers face difficult life situations.

Design.  This is a descriptive and comparative cross‐sectional study using qualitative methods.

Methods.  The convenience sample (n = 36) comprised 11 carers of older people on a nursing home placement waiting list in Norway and 11 nurses caring for these older people. Every one willingly participated in interviews that were transcribed and analysed by qualitative content analysis.

Results.  Various similarities and differences between nurses’ and carers’ appraisals were found. Complex ethical issues of justice, equality, autonomy, beneficence and justifiability in nursing were involved in decision making concerning nursing home placement. Four categories constructed were: ‘appraising nursing home to be the level of care needed’, ‘appraising the older people as able to continue living at home’, ‘being ambivalent about nursing home placement’ and ‘being sceptical about use of coercion regarding nursing home placement’.

Conclusions.  Not all of the older people awaiting nursing home placements could be placed in nursing homes when beds became available. The situations were complex and involved ethical issues.

Relevance to clinical practice.  Despite insufficient resources in home health care, providing appropriate support for older people and their carers means that nurses have to consider individual concerns in each situation, cooperate with carers, respect their appraisals of needs and argue for the timely nursing home placement of older people.