bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering animal models of dystonia
Authors: Oleas Janneth , Yokoi Fumiaki , DeAndrade Mark P. , Pisani Antonio , Li Yuqing
Published: July 2013

Dystonia is a neurological disorder characterized by abnormal involuntary movements that are prolonged and often cause twisting and turning. Several genetically modified worms, fruit flies, and rodents have been generated as models of genetic dystonias, in particular DYT1, DYT11, and DYT12 dystonias. Although these models do not show overt dystonic symptoms, the rodent models exhibit motor deficits in specialized behavioral tasks, such as the rotarod and beam‐walking tests. For example, in a rodent model of DYT12 dystonia, which is generally stress triggered, motor deficits are observed only after the animal is stressed. Moreover, in a rodent model of DYT1 dystonia, the motor and electrophysiological deficits can be rescued by trihexyphenidyl, a common anticholinergic medication used to treat dystonic symptoms in human patients. Biochemically, the DYT1 and DYT11 animal models also share some similarities to patients, such as a reduction in striatal D2 dopamine receptor and binding activities. In addition, conditional knockout mouse models for DYT1 and DYT11 dystonia demonstrate that loss of the causal dystonia‐related proteins in the striatum leads to motor deficits. Interestingly, loss of the DYT1 dystonia causal protein in Purkinje cells shows an improvement in motor performance, suggesting that gene therapy targeting of the cerebellum or intervention in its downstream pathways may be useful. Finally, recent studies using DYT1 dystonia worm and mouse models led to a potential novel therapeutic agent, which is currently undergoing clinical trials. These results indicate that genetic animal models are powerful tools to elucidate the pathophysiology and to further develop new therapeutics for dystonia. © 2013 Movement Disorder Society
Comparative biology of sperm factors and fertilization‐induced calcium signals across the animal kingdom
Authors: Kashir Junaid , Deguchi Ryusaku , Jones Celine , Coward Kevin , Stricker Stephen A.
Published: July 2013

Fertilization causes mature oocytes or eggs to increase their concentrations of intracellular calcium ions (Ca2+) in all animals that have been examined, and such Ca2+ elevations, in turn, provide key activating signals that are required for non‐parthenogenetic development. Several lines of evidence indicate that the Ca2+ transients produced during fertilization in mammals and other taxa are triggered by soluble factors that sperm deliver into oocytes after gamete fusion. Thus, for a broad‐based analysis of Ca2+ dynamics during fertilization in animals, this article begins by summarizing data on soluble sperm factors in non‐mammalian species, and subsequently reviews various topics related to a sperm‐specific phospholipase C, called PLCζ, which is believed to be the predominant activator of mammalian oocytes. After characterizing initiation processes that involve sperm factors or alternative triggering mechanisms, the spatiotemporal patterns of Ca2+ signals in fertilized oocytes or eggs are compared in a taxon‐by‐taxon manner, and broadly classified as either a single major transient or a series of repetitive oscillations. Both solitary and oscillatory types of fertilization‐induced Ca2+ signals are typically propagated as global waves that depend on Ca2+ release from the endoplasmic reticulum in response to increased concentrations of inositol 1,4,5‐trisphosphate (IP3). Thus, for taxa where relevant data are available, upstream pathways that elevate intraoocytic IP3 levels during fertilization are described, while other less‐common modes of producing Ca2+ transients are also examined. In addition, the importance of fertilization‐induced Ca2+ signals for activating development is underscored by noting some major downstream effects of these signals in various animals. Mol. Reprod. Dev. 80: 787–815, 2013. © 2013 Wiley Periodicals, Inc.
The biology of the germ line in echinoderms
Authors: Wessel Gary M. , Brayboy Lynae , Fresques Tara , Gustafson Eric A. , Oulhen Nathalie , Ramos Isabela , Reich Adrian , Swartz S. Zachary , Yajima Mamiko , Zazueta Vanessa
Published: July 2013

The formation of the germ line in an embryo marks a fresh round of reproductive potential. The developmental stage and location within the embryo where the primordial germ cells (PGCs) form, however, differs markedly among species. In many animals, the germ line is formed by an inherited mechanism, in which molecules made and selectively partitioned within the oocyte drive the early development of cells that acquire this material to a germ‐line fate. In contrast, the germ line of other animals is fated by an inductive mechanism that involves signaling between cells that directs this specialized fate. In this review, we explore the mechanisms of germ‐line determination in echinoderms, an early‐branching sister group to the chordates. One member of the phylum, sea urchins, appears to use an inherited mechanism of germ‐line formation, whereas their relatives, the sea stars, appear to use an inductive mechanism. We first integrate the experimental results currently available for germ‐line determination in the sea urchin, for which considerable new information is available, and then broaden the investigation to the lesser‐known mechanisms in sea stars and other echinoderms. Even with this limited insight, it appears that sea stars, and perhaps the majority of the echinoderm taxon, rely on inductive mechanisms for germ‐line fate determination. This enables a strongly contrasted picture for germ‐line determination in this phylum, but one for which transitions between different modes of germ‐line determination might now be experimentally addressed. Mol. Reprod. Dev. 81: 679–711, 2014. © 2014 Wiley Periodicals, Inc.
Free‐breathing phase contrast MRI with near 100% respiratory navigator efficiency using k‐space‐dependent respiratory gating
Authors: Akçakaya Mehmet , Gulaka Praveen , Basha Tamer A. , Ngo Long H. , Manning Warren J. , Nezafat Reza
Published: July 2013

Purpose

To investigate the efficacy of a novel respiratory motion scheme, where only the center of k‐space is gated using respiratory navigators, versus a fully respiratory‐gated acquisition for three‐dimensional flow imaging.

Methods

Three‐dimensional flow images were acquired axially using a gradient echo sequence in a volume, covering the ascending and descending aorta, and the pulmonary artery bifurcation in 12 healthy subjects (33.2 ± 15.8 years; five men). For respiratory motion compensation, two gating and tracking strategies were used with a 7‐mm gating window: (1) All of k‐space acquired within the gating window (fully gated) and (2) central k‐space acquired within the gating window, and the remainder of k‐space acquired without any gating (center gated). Each scan was repeated twice. Stroke volume, mean flow, peak velocity, and signal‐to‐noise‐ratio measurements were performed both on the ascending and on the descending aorta for all acquisitions, which were compared using a linear mixed‐effects model and Bland–Altman analysis.

Results

There were no statistical differences between the fully gated and the center‐gated strategies for the quantification of stroke volume, peak velocity, and mean flow, as well as the signal‐to‐noise‐ratio measurements. Furthermore, the proposed center‐gated strategy had significantly shorter acquisition time compared to the fully gated strategy (13:19 ± 3:02 vs. 19:35 ± 5:02, P < 0.001).

Conclusions

The proposed novel center‐gated strategy for three‐dimensional flow MRI allows for markedly shorter acquisition time without any systematic variation in quantitative flow measurements in this small group of healthy volunteers. Magn Reson Med 71:2172–2179, 2014. © 2013 Wiley Periodicals, Inc.
Relaxation by amplitude modulation: A rapid T1 measurement method
Authors: Zou Xiaowei , Brown Truman R.
Published: July 2013

Purpose

A novel longitudinal relaxation time (T1) measurement method using complex amplitude modulation is presented.

Theory

The method applies a series of inversion pulses to the imaged region in accordance with a binary modulation sequence. The longitudinal magnetization acquired in a given pulse repetition time (TR) interval is the sum of the individual longitudinal magnetization recovered during each previous TR interval, weighted by T1 decay factors and the combined effect of all the radiofrequency pulses they have experienced. The demodulated signal for each voxel is an exponential curve with a decaying rate determined by T1 and the acquisition flip angle θ.

Methods

Sequences using a 15‐cycle pseudorandom binary code were implemented on Siemens 3T Trio with standard gradient echo readout and multislice gradient echo‐planar imaging. The sequences were tested on T1 phantoms and human and compared against inversion recovery method.

Results

Our studies on phantoms and a human volunteer show that T1 estimated from this method is very accurate and well reproducible. The average scan time is ∼1.6 s per slice (full k‐space gradient echo‐planar imaging with matrix size 128 × 128).

Conclusion

The current protocol is almost twice as fast as two fastest existing methods. Optimizing protocols and incorporating common acceleration techniques will make it even faster. Magn Reson Med 71:2155–2165, 2014. © 2013 Wiley Periodicals, Inc.
Quantified intermediate water oxygenation history of the NE Pacific: A new benthic foraminiferal record from Santa Barbara basin
Authors: Ohkushi K. , Kennett J. P. , Zeleski C. M. , Moffitt S. E. , Hill T. M. , Robert C. , Beaufort L. , Behl R. J.
Published: July 2013

The oxygen minimum zone (OMZ) of the late Quaternary California margin experienced abrupt and dramatic changes in strength and depth in response to changes in intermediate water ventilation, ocean productivity, and climate at orbital through millennial time scales. Expansion and contraction of the OMZ is exhibited at high temporal resolution (107–126 year) by quantitative benthic foraminiferal assemblage changes in two piston cores forming a vertical profile in Santa Barbara Basin (569 m, basin floor; 481 m, near sill depth) to 34 and 24 ka, respectively. Variation in the OMZ is quantified by new benthic foraminiferal groupings and new dissolved oxygen index based on documented relations between species and water‐mass oxygen concentrations. Foraminiferal‐based paleoenvironmental assessments are integrated with principal component analysis, bioturbation, grain size, CaCO3, total organic carbon, and δ13C to reconstruct basin oxygenation history. Fauna responded similarly between the two sites, although with somewhat different magnitude and taxonomic expression. During cool episodes (Younger Dryas and stadials), the water column was well oxygenated, most strongly near the end of the glacial episode (17–16 ka; Heinrich 1). In contrast, the OMZ was strong during warm episodes (Bølling/Allerød, interstadials, and Pre‐Boreal). During the Bølling/Allerød, the OMZ shoaled to <360 m of contemporaneous sea level, its greatest vertical expansion of the last glacial cycle. Assemblages were then dominated by Bolivina tumida, reflecting high concentrations of dissolved methane in bottom waters. Short decadal intervals were so severely oxygen‐depleted that no benthic foraminifera were present. The middle to late Holocene (6–0 ka) was less dysoxic than the early Holocene.
Early pregnancy failure as a training tool for chorionic villus sampling
Authors: Nicholas Sara , Orzechowski Kelly , Potti Sushma , Baxter Jason , Berghella Vincenzo , Weiner Stuart
Published: July 2013

Objectives

The goal of this study is to evaluate the success of a training program in chorionic villus sampling (CVS) of early pregnancy failure (EPF) for maternal‐fetal medicine (MFM) fellows.

Methods

We conducted a retrospective review of a new training program in CVS for MFM fellows. Women with EPF up to 13 weeks estimated gestational age were offered inclusion in our program and counseled on alternatives. Transcervical CVS was performed for both fellow education and cytogenetic diagnosis. The primary outcome was a successful diagnosis, and the secondary outcome was cell growth by fellow experience.

Results

Thirty‐nine patients diagnosed with EPF from December 2011 to March 2013 underwent CVS. Villi obtained via CVS yielded a diagnosis in 62% of cases. CVS samples with successful karyotype had more villi but were otherwise similar. CVS by experience showed a trend towards increased success and villi volume after the first five procedures. Abnormal results were obtained in 72% of cases, 15% of which led to changes in care.

Conclusion

CVS of EPF is an option for the training of MFM fellows as it was acceptable to most patients, and the majority of CVS specimens yielded a karyotype diagnosis. © 2013 John Wiley & Sons, Ltd.
Influence of electrospinning parameters on poly(hydroxybutyrate) electrospun membranes fiber size and distribution
Authors: Correia Daniela M. , Ribeiro Clarisse , Ferreira José C.C. , Botelho Gabriela , Ribelles José Luis Gomez , Lanceros‐Méndez Senentxu , Sencadas Vitor
Published: July 2013

Poly(hydroxybutyrate) (PHB) obtained from sugar cane waste was dissolved in a blend of chloroform and dimethylformamide (DMF) and electrospun at 40°C. By adding DMF to the solution, the electrospinning process for the PHB polymer becomes more stable, allowing complete polymer crystallization during the jet travelling between the tip and the grounded collector. The influence of processing parameters on fiber size and distribution was systematically studied. It was observed that an increase of tip inner diameter promotes a decrease of the fiber average size and a broader distribution. Conversely, an increase of the electric field and flow rate produces an increase of fiber diameter until a maximum of ∼2.0 µm but for electric fields higher than 1.5 kV cm−1, a decrease of the fiber diameter was observed. Polymer crystalline phase seems to be independent of the processing conditions and a crystallinity degree of 53% was found. Moreover, thermal degradation of the as‐spun membrane occurs in single step degradation with activation energy of 91 kJ mol−1. Furthermore, MC‐3T3‐E1 cell adhesion was not inhibited by the fiber mats preparation, indicating their potential use for biomedical applications. POLYM. ENG. SCI., 54:1608–1617, 2014. © 2013 Society of Plastics Engineers
Barriers and facilitators to effective communication experienced by patients with malignant lymphoma at all stages after diagnosis
Authors: van Bruinessen Inge Renske , van Weel‐Baumgarten Evelyn M. , Gouw Hans , Zijlstra Josée M. , Albada Akke , van Dulmen Sandra
Published: July 2013

Objective

This study aims to gain insight into patient‐perceived communication barriers and facilitators at different stages after the diagnosis of malignant lymphoma. We have detected patterns to explain when these factors influence communication predominantly.

Method

A qualitative approach was applied, derived from the context mapping framework. A total of 28 patients completed a set of assignments about their experiences with provider‐patient communication during medical consultations. Subsequently, these patients and nine companions shared their experiences during a semistructured (group) interview, which was recorded on audiotape. The audiotapes and assignments were analysed with MAXQDA software.

Results

From the patients' viewpoint, communicating effectively appears to depend on their own attributes (e.g. emotions), the health care professionals' attributes (e.g. attitude) and external factors (e.g. time pressure). Three patient communication states were identified: (i) overwhelmed, passive; (ii) pro‐active, self‐motivated; and (iii) proficient, empowered. Patients seem to behave differently in the three communication states.

Conclusions

This study lists patient‐perceived communication barriers and facilitators and identifies three different communication states, which indicate when certain barriers and facilitators are encountered.

Practical implications

These findings may support health care professionals to tailor the provision of support and information and remove communication barriers accordingly. Additionally, they provide input for interventions to support patients in effective communication. Copyright © 2013 John Wiley & Sons, Ltd.
Injection and temperature dependent carrier recombination rate and diffusion length in freestanding CVD diamond
Authors: Ščajev Patrik , Gudelis Vytautas , Tallaire Alexandre , Barjon Julien , Jarašiūnas Kęstutis
Published: July 2013

We applied time‐resolved nonlinear optical techniques for investigation of carrier recombination and diffusion processes in a 420 μm thick CVD diamond, relatively free from structural and point defects. Injection of 1015–1017 cm−3 carrier density by two‐photon excitation and monitoring free carrier absorption decay in 80–800 K range provided lifetime of 720 ns at T ≥ 300 K. At low temperatures, a linear increase of the carrier recombination rate with the injection level was fitted by an effective bimolecular recombination coefficient B = 10−11–10−9 cm3 s−1 and attributed to the impact of excitons and biexcitons, contributing to phonon‐assisted indirect Auger recombination. At high temperatures, increase of recombination rate was governed by Coulomb enhanced direct Auger process with a 520 meV threshold. An ambipolar carrier mobility with its peak value of ∼1500 cm2 V−1 s−1 at room temperature was determined by transient grating technique at ∼2 × 1015 cm−3 excess carrier density. A strong decrease of mobility at higher injections revealed the role of carrier‐carrier scattering, exciton formation and bandgap renormalization. The simultaneous measurements of carrier lifetime and diffusivity provided carrier diffusion length, which varied in a 1–50 μm range, depending on injection and temperature.
Crystallite size dependent carrier recombination rate and thermal diffusivity in undoped and boron doped CVD diamond layers
Authors: Ščajev P. , Nargelas S. , Jarašiūnas K. , Kisialiou I. , Ivakin E. , Deferme W. , D'Haen J. , Haenen K.
Published: July 2013

Carrier dynamics under interband carrier injection conditions (213 nm) was studied in undoped and boron‐doped microcrystalline diamond layers with different grain size. The grain size, determined by scanning electron microscopy and electron backscattered diffraction, varied from 130 μm on the growth side to ∼1–2 μm on the nucleation side of a 1.0 mm‐thick undoped layer. Carrier lifetimes measured by differential transmittivity (DT) technique varied from 1 to 4 ns on the growth side to ∼220 ps on the nucleation side. Also the carrier diffusivity was found higher on the growth side. The B‐doped layer with 40 μm grain size at the growth side exhibited 380 ps carrier lifetime, which decreased to 130 ps on the nucleation side. Even shorter lifetimes (∼100–200 ps and ∼10 ps, correspondingly) were revealed in this layer by differential reflectivity decay due to impact of subsurface defects. Therefore we conclude that the recombination rate in presence of large grains is dominated by bulk non‐radiative traps, as diffusion time of carriers to reach grain boundaries is much longer (few μs). An impact of grain boundaries to recombination is expected in case of smaller grains. Thermal grating decay provided values of thermal diffusivity Dth in the range of 12–6 cm2 s−1, respectively, on the growth and nucleation side of the layers, and its decrease with reduction of grain size was attributed to phonon scattering on grain boundaries.
Optical/electrical correlations in ZnO: The plasmonic resonance phase diagram
Authors: Look D. C. , Droubay T. C. , Chambers S. A.
Published: July 2013

The Drude equation for dielectric constant ϵ(E) depends on four parameters: ϵ∞, effective mass m*, optical mobility µopt, and optical carrier concentration nopt. By solving this equation at ϵ(Eres) = 0, we obtain a relationship between µopt and nopt at constant plasmonic resonance energy Eres [or wavelength λres (µm) = 1.2395/Eres (eV)]. A family of µopt versus nopt curves covering a range of λres values (including the limiting wavelength λres = ∞) constitutes a plasmonic resonance phase diagram (PRPD) for a semiconductor defined by only ϵ∞ and m*. The PRPD is a convenient instrument that allows an immediate prediction of λres from Hall‐effect measurements of µH and nH. We apply the PRPD analysis to a series of ten ZnO samples grown by pulsed laser deposition at 200 °C in an ambient of 33%H2:67%Ar and annealed in 25 °C steps for 10 min in air at various temperatures from 400 to 600 °C. For the samples annealed at 550 °C or lower, the µH/nH points yield predicted values of λres that range from 1.07 to 2.80 µm; however, the 575 and 600 °C samples are predicted to have no resonance at all. Reflectance curves for the eight samples annealed up to 550 °C decrease slowly from 6 eV down to about Eres = 0.5–1.15 eV, and then increase rapidly for E < Eres. In contrast, there is no such resonance‐related increase for the 575 and 600 °C samples. Satisfactory agreement is found between the reflectance minima and the Hall‐effect‐predicted values of λres.
Investigation of the robustness of two models for assessing synergy in pre‐clinical drug combination studies
Authors: Whitehead Anne , Su Ting‐Li , Thygesen Helene , Sperrin Matthew , Harbron Chris
Published: July 2013

Pre‐clinical studies may be used to screen for synergistic combinations of drugs. The types of in vitro assays used for this purpose will depend upon the disease area of interest. In oncology, one frequently used study measures cell line viability: cells placed into wells on a plate are treated with doses of two compounds, and cell viability is assessed from an optical density measurement corrected for blank well values. These measurements are often transformed and analysed as cell survival relative to untreated wells. The monotherapies are assumed to follow the Hill equation with lower and upper asymptotes at 0 and 1, respectively. Additionally, a common variance about the dose–response curve may be assumed. In this paper, we consider two models for incorporating synergy parameters. We investigate the effect of different models of biological variation on the assessment of synergy from both of these models. We show that estimates of the synergy parameters appear to be robust, even when estimates of the other model parameters are biased. Using untransformed measurements provides better coverage of the 95% confidence intervals for the synergy parameters than using transformed measurements, and the requirement to fit the upper asymptote does not cause difficulties. Assuming homoscedastic variances appears to be robust. The added complexity of determining and fitting an appropriate heteroscedastic model does not seem to be justified. Copyright © 2013 John Wiley & Sons, Ltd.
Bayesian methods for design and analysis of safety trials
Authors: Price Karen L. , Amy Xia H. , Lakshminarayanan Mani , Madigan David , Manner David , Scott John , Stamey James D. , Thompson Laura
Published: July 2013

Safety assessment is essential throughout medical product development. There has been increased awareness of the importance of safety trials recently, in part due to recent US Food and Drug Administration guidance related to thorough assessment of cardiovascular risk in the treatment of type 2 diabetes. Bayesian methods provide great promise for improving the conduct of safety trials. In this paper, the safety subteam of the Drug Information Association Bayesian Scientific Working Group evaluates challenges associated with current methods for designing and analyzing safety trials and provides an overview of several suggested Bayesian opportunities that may increase efficiency of safety trials along with relevant case examples. Copyright © 2013 John Wiley & Sons, Ltd.
A hybrid approach to achieving both marginal and conditional balances for stratification variables in sequential clinical trials
Authors: Lin Yunzhi , Su Zheng
Published: July 2013

Various methods exist in the literature for achieving marginal balance for baseline stratification variables in sequential clinical trials. One major limitation with balancing on the margins of the stratification variables is that there is an efficiency loss when the primary analysis is stratified. To preserve the efficiency of a stratified analysis one recently proposed approach balances on the crossing of the stratification variables included in the analysis, which achieves conditional balance for the variables. A hybrid approach to achieving both marginal and conditional balances in sequential clinical trials is proposed, which is applicable to both continuous and categorical stratification variables. Numerical results based on extensive simulation studies and a real dataset show that the proposed approach outperforms the existing ones and is particularly useful when both additive and stratified models are planned for a trial. Copyright © 2013 John Wiley & Sons, Ltd.
REVISION OF THE BIOLOGICAL MONITORING WORKING PARTY (BMWP) SCORE SYSTEM: DERIVATION OF PRESENT‐ONLY AND ABUNDANCE‐RELATED SCORES FROM FIELD DATA
Authors: Paisley M. F. , Trigg D. J. , Walley W. J.
Published: July 2013

The Biological Monitoring Working Party (BMWP) score system was introduced in 1980 to provide an index of river water quality for England and Wales based on aquatic macroinvertebrates. The score allocated to each taxon was set by a group of expert river biologists on the basis of their collective experience of the taxon's sensitivity to organic pollution. This paper describes an objective reappraisal of these subjectively derived scores by the statistical analysis of a large and comprehensive database of field data. Two different methods of using biological and environmental data were evaluated as a basis for revising BMWP scores, both of which accounted for variations in site type. One method, Modified New Walley–Hawkes (MNWH), used a modified average score per taxon (MASPT) as its ranking metric and required analyses performed on separated data sets divided into three site types. The other method used the environmental quality index based on MASPT (EQIMASPT) to provide its ranking metric. Both of these methods involved the use of modified BMWP values for Oligochaeta and Chironomidae for reasons that are explained. Following evaluation, the MNWH method was chosen to derive present‐only and abundance‐related scores for the BMWP taxa, 19 additional taxa mostly from the order Diptera, and 16 extra taxa resulting from the splitting of eight BMWP composite taxa. The MNWH scores were generally in keeping with those derived in an earlier study, except for a few rare taxa that were represented by few samples in that study. The UK Regulatory Authorities intend adopting a new index based on the MNWH scores, and this is given in two appendices. Copyright © 2013 John Wiley & Sons, Ltd.
Morphological feature extraction for statistical learning with applications to solar image data
Authors: Stenning David C. , Lee Thomas C. M. , van Dyk David A. , Kashyap Vinay , Sandell Julia , Young C. Alex
Published: July 2013

Many areas of science are generating large volumes of digital image data. In order to take full advantage of the high‐resolution and high‐cadence images modern technology is producing, methods to automatically process and analyze large batches of such images are needed. This involves reducing complex images to simple representations such as binary sketches or numerical summaries that capture embedded scientific information. Using techniques derived from mathematical morphology, we demonstrate how to reduce solar images into simple ‘sketch’ representations and numerical summaries that can be used for statistical learning. We demonstrate our general techniques on two specific examples: classifying sunspot groups and recognizing coronal loop structures. Our methodology reproduces manual classifications at an overall rate of 90% on a set of 119 magnetogram and white light images of sunspot groups. We also show that our methodology is competitive with other automated algorithms at producing coronal loop tracings and demonstrate robustness through noise simulations. © 2013 Wiley Periodicals, Inc. Statistical Analysis and Data Mining, 2013
Linguistic Challenges in Mendelian Genetics: Teachers’ Talk in Action
Authors: THÖRNE KARIN , GERICKE NIKLAS M. , HAGBERG MARIANA
Published: July 2013

This study investigates Swedish teachers’ use of language when teaching Mendelian genetics in compulsory school. The primary objective of the study is to explore how teachers use the related concepts gene, allele, and anlag (a Swedish variant of the German word anlage) and how these are related to trait, central relations that have been identified as problematic in genetics education. Four teachers were recorded while teaching genetics. The empirical data consist of 45 recorded lessons. The teachers’ verbal communications were analyzed using a linguistic framework called thematic pattern analysis. The results showed a predominant use of the word anlag over gene, whereas there was a total lack of use of the word allele. The word anlag was used to mean both gene and trait. Anlag was also used as a synonym for allele. The teachers’ language conveyed four categories of meanings regarding the gene‐to‐trait relationship: genes control traits, are identified by traits, have traits, or are traits. This study thus highlights several linguistic challenges in the teaching of Mendelian genetics that might affect students’ learning. Moreover, the study exemplifies how a linguistics methodology can be used to investigate science teaching. © 2013 Wiley Periodicals, Inc. Sci Ed 97:695–722, 2013
Mental Well‐Being Mediates the Relationship between Perceived Stress and Perceived Health
Authors: Teh Hui Chian , Archer Josephine A. , Chang Weining , Chen SH Annabel
Published: July 2013

The association between stress and health has been well researched in the past; however, comparatively few mediators have been tested to understand the underlying mechanism. With increasing awareness on mental well‐being, this study evaluated the relationship between perceived stress and perceived health and examined mental well‐being as a mediator. Two‐hundred undergraduates aged 21 to 26 years completed the English Perceived Stress Scale, Health Status Questionnaire and Asian Mental Well‐Being Scale that assess perceived stress, perceived health and mental well‐being, respectively. Factor analysis and structural equation modelling on the Perceived Stress Scale replicated the reported two‐factor structure after excluding an insignificant item. Linear multiple regression analyses indicated that perceived stress was negatively associated with perceived health. Results showed that mental well‐being partially mediated the relationship between perceived stress and perceived health, although it is acknowledged that this association could be bidirectional. Findings from the present study suggest that future research could focus on reducing stress and improving mental well‐being to alleviate the effect of stress on health. Copyright © 2013 John Wiley & Sons, Ltd.
Modelling for Insight: The Case of Dementia in Singapore
Authors: Thompson James P. , Riley Crystal M. , Eberlein Robert L.
Published: July 2013

Many nations have rapidly ageing populations and consequently face important health care policy issues, including a need to address the care and treatment of individuals afflicted with ageing‐related dementia. To help inform policymakers in Singapore concerned with dementia, we constructed a system dynamics model that represents changing population characteristics, incidence and prevalence of dementia, and a population‐level natural history of this pernicious condition. In the model‐building process, we encountered an unexpected simulation outcome that led to valuable insights. This article (i) describes how a difference between measured census data and the simulated population led to improvements in our population modelling, (ii) introduces a novel and generalizable means to simulate how the prevalence of mild, moderate, and severe dementia is likely to change over the next 20 years, and (iii) provides a comparison between two means of prevalence projection. Copyright © 2013 John Wiley & Sons, Ltd.
Finite element modeling and parametric analysis of timber–steel hybrid structures
Authors: Li Zheng , He Minjuan , Lam Frank , Li Minghao , Ma Renle , Ma Zhong
Published: July 2013

This paper presents finite element modeling and a parametric analysis of prototype timber–steel hybrid structures, which are composed of steel moment‐resisting frames and infill wood‐frame shear walls. A user‐defined element was developed to model the behavior of the infill wood shear walls based on the concept of pseudo‐nail model. The element was implemented as a subroutine in a finite element software package abaqus. The model was verified by reversed cyclic test results and further used in a parametric analysis to investigate the lateral performance of timber–steel hybrid shear walls with various structural configurations. The results showed that the infill wall was quite effective within small drift ratios, and the elastic lateral stiffness of the hybrid shear wall increased when a stronger infill wall was used. In order to ensure the structural efficiency of the hybrid shear wall system, it is beneficial to use relatively strong timber–steel bolted connections to make sure the shear force can be transferred effectively between the steel frame and the infill wall. Copyright © 2013 John Wiley & Sons, Ltd.
Drawing Their Way Into Writing: Culturally and Linguistically Diverse Students Finding Voice Through Mini‐Novelas
Authors: Wessels Stephanie , Herrera Socorro G.
Published: July 2013

Writing can be a difficult task for many students in today's classrooms; however, for students who are culturally and linguistically diverse (CLD), writing can be especially difficult. These students often are in the process of developing their facility with the English language, and they possess cultural backgrounds that differ from those of many of their peers and teachers. In addition to these challenges, they face the typical difficulties of selecting ideas to write about for their stories. One way to tap into the cultural backgrounds of Spanish‐speaking CLD students is through the use of a strategy called the mini‐novela. A mini‐novela allows students to initially draw their stories and then write an accompanying narrative. It also allows students to use their cultural knowledge and the process of visualization as bridges to images and words that transform writing into a personally relevant, meaningful experience.
Young Learners and Lexical Awareness: Children's Engagement With Wordlists and Concordances
Authors: MacGregor Alex
Published: July 2013

Sinclair (1991) found that lexical analysis can be overcomplicated, yet Johns (1994) called for investigation into whether corpus analysis can motivate beginners and near‐beginners. The findings of this research suggest that young EFL learners can enjoy using corpus analysis tools (wordlists and concordances) to identify, classify, and generalize about English. The teacher‐researcher developed a series of classroom activities in which students created wordlists and discovered and recorded collocations. Quantitative data gathered over 1 year from yes/no and ranking questions indicate that students found the activities enjoyable, and 230 write‐in comment sheets provided qualitative data that support the motivational impact of the activities. Findings suggest that as corpora, particularly of children's language, are created and expanded upon, it is vital that classroom activities developed to target meaningful young learner language present this relevant language in an enjoyable, engaging manner.
The Impact of 3 exotic, invasive grasses in the Southeastern United States on wildlife
Authors: Barnes Thomas G. , DeMaso Stephen J. , Bahm Matt A.
Published: July 2013

Little is known about the impacts and effects of exotic, invasive grasses on wildlife in the Southeast United States. We selected 3 species of exotic grasses common to the Southeast and review the literature on their regional distribution, ecosystem impacts, wildlife impacts, and management. These grasses have the potential to harm indigenous wildlife species, such as northern bobwhite (Colinus virginianus), that need grasslands with a shrub component for nesting, brood‐rearing, and loafing. These exotic, invasive grasses are sod‐forming in nature, typically forming dense monotypic stands that provide little bare ground and have low plant species and insect diversity. Furthermore, it appears that wildlife do not prefer to consume these plant species. Control is often difficult and usually requires the use of herbicides in combination with mechanical treatment, such as disking, to provide adequate habitat. Attempts should be encouraged to convert these idle grasslands to a mixture of native grasses and forbs to make stands more suitable for wildlife species. We provide suggestions for future research and management needs regarding exotic, invasive grasses and wildlife in the Southeast United States. © 2013 The Wildlife Society.
Ternary Phase Diagram of β‐Sitosterol–γ‐Oryzanol–Canola Oil
Authors: AlHasawi F. M. , Rogers M. A.
Published: July 2013

β‐Sitosterol and γ‐oryzanol have been shown to form unique structures in canola oil that have the potential to act as saturated and trans fat replacers [1–7]. The ternary phase, reported herein, illustrates numerous interesting physical systems. At high canola oil ratios with low β‐sitosterol and γ‐oryzanol concentrations, the system has a crystal structure capable of mimicking fat crystal networks. Four mesophases are identified based on Bragg's ratios using small angle X‐ray scattering. Two mesophases are lamellar crystals, one is the cubic P phase, and the fourth is an amorphous material due to the low solids content. Wide‐angle X‐ray further subcategorized the phases based on polymorphic divisions of the hydrocarbon side chain packing. In all, six distinct phases are reported, ranging from lamellar crystals, to liquid crystals to what appears to be a lipid glass.
The Role of Peracetic Acid in Bloodmeal Decoloring
Authors: Hicks Talia M. , Verbeek C. J. R. , Lay M. C. , Manley‐Harris M.
Published: July 2013

Hydrogen peroxide (HP) can degrade soluble heme, forming yellow or colorless degradation products. Thermal treatment during bloodmeal production changes the conformation of oxyhemoglobin trapping heme in hydrophobic protein regions or forms methemoglobin (metHb) heme which catalytically removes HP. As a result, HP can only degrade a portion of the heme present in bloodmeal leading to poor decoloring. Equilibrium peracetic acid (PAA) solutions can effectively decolor bloodmeal. This work assessed the ability of PAA to decolor bloodmeal and the mechanism by which it occurs. The inability of HP to decolor bloodmeal is determined by the fact that it is unable to permanently degrade metHb heme, or hydrophobically trapped heme. Addition of organic acids to HP led to significant swelling of the protein chains but also to poorer decoloring and lower HP consumption compared to PAA. This suggested that in the case of PAA solutions, where bleaching was facile, the reason PAA solutions are capable of decoloring bloodmeal was due to the action of the PAA molecule against heme, whereas HP and acetic (ethanoic) acid played only minor roles in total bleaching. The decolored protein powder has reduced odor and whiter color, and is suitable for applications such as bioplastics.
Evidence-based practice for individuals or groups: let’s make a difference
Authors: De Groot M. , Van der Wouden J. M. , Van Hell E. A. , Nieweg M. B.
Published: July 2013

The aim of applying science into practice is to deliver high-quality health care.
Thinking about teaching the necessary accompanying skills, a distinction can be made
between using evidence for individual patient care and using scientific knowledge for
the development of protocols or guidelines for groups of patients or professionals. In
this paper, these two ways of applying science into practice are being considered. We
plea for explicating the differences between the individual patient and a group of
patients or professionals when applying scientific knowledge in the decision-making
process. The acknowledgment of these differences facilitates the teaching of the
accompanying competences and different CanMEDS roles.
Reversal effect of monoisoamyl dimercaptosuccinic acid (MiADMSA) for arsenic and lead induced perturbations in apoptosis and antioxidant enzymes in developing rat brain
Authors: Sannadi Saritha , Kadeyala Praveen Kumar , Gottipolu Rajarami Reddy
Published: July 2013

Oxidative stress (OS) has been implicated in the pathophysiology of many neurodegenerative disorders. Several studies have shown that exposure to arsenic (As) and lead (Pb) produces oxidative stress, one of the most noted molecular mechanisms for the neurotoxicity of these metals. In the present study, we examined the effect of combined exposure to these metals (As and Pb) on the activity levels of antioxidant enzymes and apoptotic marker enzymes in brain regions (cerebral cortex, hippocampus and cerebellum) of rats at postnatal day (PND) 21, 28 and 3 months age and compared the toxicity levels with individual metals (As or Pb). Further, we also evaluated the therapeutic efficacy of a chelating agent, monoisoamyl dimercaptosuccinic acid (MiADMSA) against arsenic and lead induced developmental neurotoxicity. Pregnant rats were exposed to sodium meta‐arsenite (50 ppm) and lead acetate (0.2%) individually, and in combination (As = 25 ppm + Pb = 0.1%) via drinking water throughout perinatal period (GD 6 to PND 21). MiADMSA (50 mg/kg, orally through gavage) was given for three consecutive days to the PND 18 pups (i.e., PND 18 to PND 20). Exposure to metal mixture resulted in a significant decrease in the activity levels of antioxidant enzymes such as manganese‐superoxide dismutase (Mn‐SOD), Cu/Zn superoxide dismutase (Cu/Zn‐SOD), catalase (CAT) and glutathione peroxidase (GPx) while the malondialdehyde (MDA) levels and mRNA expression levels of caspase‐3 and caspase‐9 were significantly increased in all the three brain regions. The observed alterations were greater with exposure to metal mixture than individual metals (As or Pb) and the changes were more prominent at PND 28 and greater in cerebral cortex than hippocampus and cerebellum. Interestingly, chelation therapy with MiADMSA showed significant recovery in antioxidant enzymes, lipid peroxidation and gene expression levels of caspase‐3 and caspase‐9. From these findings, it can be concluded that combined exposure to As and Pb showed an additive effect on antioxidant enzymes than individual metal exposure and chelation therapy with MiADMSA significantly reversed the As and Pb induced apoptosis and oxidative stress, a major contributing factor to neurotoxicity.
Increasing Price Transparency: Implications of Consumer Price Posting for Consumers’ Haggling Behavior and a Seller's Pricing Strategies
Authors: Zhang Xubing , Jiang Bo
Published: July 2013

In an attempt to gain a better position in haggling, consumers often seek a seller's pricing information (e.g., whether the posted price is negotiable, the discount and transaction prices) before going to that seller. Although traditionally difficult to obtain, such information is becoming increasingly available due to consumer price posting (CPP), whereby consumers post and share their purchase price information on the Internet. In this analytical study, we consider a market in which a seller, who chooses between a fixed price policy and a haggling policy, serves two types of consumers who differ in their willingness to pay and haggling costs. We explore how CPP can affect consumers’ behavior and the seller's pricing strategies (i.e., pricing policy and the associated prices). In the absence of CPP, our model features a two-sided uncertainty: the seller does not know individual consumer's type and thus may find it optimal to use a haggling policy to price discriminate consumers, whereas consumers do not readily observe the seller's cost type and pricing policy, and thus are uncertain whether their haggling will be fruitful. In the presence of CPP, consumers’ uncertainty about the seller's pricing policy is resolved. Because CPP can improve price transparency, inhibit consumers’ acceptance of a posted price and spur price haggling, it seems apparent that it should benefit consumers and hurt the seller. However, our analysis shows that CPP can lead to fewer purchases, higher prices and even a greater seller profit. It further shows that although CPP surely increases information accessibility, it can also reduce the amount of information available to consumers. These results are in sharp contrast to the conventional wisdom in the literature.
Implantable sensors for heart failure monitoring
Authors: Shasha Liu P. , Tse Hung‐Fat
Published: July 2013

Over the last decade, there has been a surge in the implantations of devices for cardiac resynchronization therapy (CRT), with increasing recognition of their value in the management of medically refractory heart failure (HF). With this exponential growth, the need to offer the best quality of care after implantation has entailed an increase in healthcare spending. Frequent in‐office follow‐ups are limited by the immense healthcare cost, while emergency hospitalizations for acute decompensation of HF further contribute to the burden.

Implantable sensors in the CRT device offer a unique opportunity for continuous monitoring of a patient's clinical HF status by measuring cardiac rhythm, intracardiac pressures, cardiac events, and physical activity, as well as detecting any device malfunction. Detecting early signs of a deteriorating clinical condition allows prompt preemptive medical intervention to optimize HF management. As a result, not only healthcare professionals will benefit from a reduction in hospitalizations and routine in‐office follow‐ups, but also patients will benefit from efficient management of their HF. This review highlights the latest available device‐based remote monitoring systems and the most up‐to‐date evidence for the use of remote monitoring in CRT.
Implantable devices in the electromagnetic environment
Authors: Santini Luca , Forleo Giovanni B. , Santini Massimo
Published: July 2013

In the last few years we are witnessing a dramatic increase in the number of CIEDs implanted. At the same time new emitters are constantly entering the marketplace and more and more medical procedures are based on electromagnetic fields as well. Therefore, the topic of the interaction of CIEDs with the EMI is a real, actual and challenging one. In the non‐medical environment several types of devices may be intentional or non‐intentional sources of EMI. Most of the studies reported in literature focused on mobile phones, metal detectors, as well as on headphones or digital players, but many other instruments and tools may generate electromagnetic fields. In the medical environment most of the attention is paid to MRI and recently new PM and MRI conditional ICDs have been developed and launched in the market, but the risk of interaction is present also with ionizing radiation, electrical nerve stimulation and electrosurgery. Pacemaker/ICD manufacturers are incorporating state of the art technology to make implantable devices less susceptible to EMI. However, patients and emitter manufacturers should be aware that limitations exist and that there is not complete immunity to EMI.