bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid Annealing of Black ZnO Thin Films Prepared by Pulsed Laser Deposition
Authors: Polyakov B. , Petruhin A. , Grigorjeva L. , Kulis P. , Tale I.
Published: March 2009

Rapid Annealing of Black ZnO Thin Films Prepared by Pulsed Laser Deposition

ZnO thin films were deposited by pulsed laser deposition (fluence 2.2 J/cm2) in vacuum on different substrates kept at room temperature. This temperature allowed for fast film growing, however the as-prepared films had low transparency. To improve this optical property, keeping up at the same time the high electric conductivity of the films, post-annealing procedures in vacuum and in air were carried out. The influence of these procedures on the optical absorption, photoluminescence and electrical properties has been investigated. It is shown that the annealing in air improves only the transparency of such a film, however its conductivity decreases markedly. In turn, vacuum annealing for 3 min. at 600° C results in better transparency of the films, with their electric conductivity kept high.
Legacy Identities: A Tale of Repression and Redemption
Authors: Wood Thomaz , Caldas Miguel P.
Published: March 2009

The concept of organizational identity became a subject of interest within the academic milieu in the mid‐1980s. In this paper, we propose the construct of legacy identities, those persistent identities that, first, endure over time at different levels of expression and, second, are comprised of resilient ideals from the past that represent the perceived persistent character of what the organization used to be. This construct is derived from a case study that portrays the radical transformation of a former state‐owned Brazilian company that became a subsidiary of a North American firm and survived the crisis that originated from its parent company’s debacle. Building on data from the case study, we develop a framework that shows the salience of different identities through time in the company and seek to explain the dynamics underlying these changes.
A Visibility Project: Learning to See How Preservice Teachers Take Up Culturally Responsive Pedagogy
Authors: Gere Anne Ruggles , Buehler Jennifer , Dallavis Christian , Haviland Victoria Shaw
Published: March 2009

This study analyzes the ways in which raced consciousness inflects developing understandings of cultural responsiveness among preservice teachers whose preparation included responses to imaginative engagement with literary texts, interactions in an underresourced school, and exploration of key concepts of culturally responsive pedagogy. The authors analyze how this preparation created spaces that made the diverse and complex understandings of cultural responsiveness held by teacher candidates and instructors visible and how raced consciousness shaped these understandings. Findings suggest that incorporation of multicultural literary texts, continual interrogation of attitudes toward race and racism, and explicit engagement with raced consciousness fosters learning about how beginning teachers take up cultural responsiveness, given the persistent stereotypes and the raced consciousness that shape their language and perceptions.
Increasing Achievement by Focusing Grade-Level Teams on Improving Classroom Learning: A Prospective, Quasi-Experimental Study of Title I Schools
Authors: Saunders William M. , Goldenberg Claude N. , Gallimore Ronald
Published: March 2009

The authors conducted a quasi-experimental investigation of effects on achievement by grade-level teams focused on improving learning. For 2 years (Phase 1), principals-only training was provided. During the final 3 years (Phase 2), school-based training was provided for principals and teacher leaders on stabilizing team settings and using explicit protocols for grade-level meetings. Phase 1 produced no differences in achievement between experimental and comparable schools. During Phase 2, experimental group scores improved at a faster rate than at comparable schools and exhibited greater achievement growth over 3 years on state-mandated tests and an achievement index. Stable school-based settings, distributed leadership, and explicit protocols are key to effective teacher teams. The long-term sustainability of teacher teams depends on coherent and aligned district policies and practices.
Inflorescences contribute more than rosettes to lifetime carbon gain in Arabidopsis thaliana (Brassicaceae)
Authors: Earley Eric J. , Ingland Bronson , Winkler Jacob , Tonsor Stephen J.
Published: March 2009

A metamorphosis from rosette to inflorescence in many annuals shifts photosynthetic tissue from a two‐dimensional array in the soil boundary layer during cool months to a three‐dimensional structure in the troposphere as spring progresses. We propose that this shift allows escape from both self‐shading and an increasingly stressful boundary layer microclimate, permitting continued increases in growth. As a first step in exploring this hypothesis, we compared the lifetime C gain, water loss, and instantaneous water use efficiency (WUE) of five Arabidopsis thaliana genotypes by measuring gas exchange across the life cycle. On average, the inflorescence contributed 55% (± 5% SE) of lifetime C gain, but only 25% of lifetime water loss. Mean inflorescence WUE was nearly fourfold that of the rosette. The inflorescence continued to fix C after rosette senescence. The percentage inflorescence: total C gain varied among genotypes, from 36% to 93%. Genotypes differed in WUE for both structures. We suggest that local climates may have selected for divergence in these traits. For many annuals and winter annuals, understanding C and water budgets and their evolution must include measures of both rosette and inflorescence gas exchange.
Ecology of leaf teeth: A multi‐site analysis from an Australian subtropical rainforest
Authors: Royer Dana L. , Kooyman Robert M. , Little Stefan A. , Wilf Peter
Published: March 2009

Teeth are conspicuous features of many leaves. The percentage of species in a flora with toothed leaves varies inversely with temperature, but other ecological controls are less known. This gap is critical because leaf teeth may be influenced by water availability and growth potential and because fossil tooth characters are widely used to reconstruct paleoclimate. Here, we test whether ecological attributes related to disturbance, water availability, and growth strategy influence the distribution of toothed species at 227 sites from Australian subtropical rainforest. Both the percentage and abundance of toothed species decline continuously from riparian to ridge‐top habitats in our most spatially resolved sample, a result not related to phylogenetic correlation of traits. Riparian lianas are generally untoothed and thus do not contribute to the trend, and there is little association between toothed riparian species and ecological attributes indicating early successional lifestyle and disturbance response. Instead, the pattern is best explained by differences in water availability. Toothed species’ proportional richness declines with proximity to the coast, also a likely effect of water availability because salt stress causes physiological drought. Our study highlights water availability as an important factor impacting the distribution of toothed species across landscapes, with significance for paleoclimate reconstructions.
In vivo study of developmental programmed cell death using the lace plant (Aponogeton madagascariensis; Aponogetonaceae) leaf model system
Authors: Wright Harrison , van Doorn Wouter G. , Gunawardena Arunika H. L. A. N.
Published: March 2009

Programmed cell death (PCD) is required for many morphological changes, but in plants it has been studied in much less detail than in animals. The unique structure and physiology of the lace plant (Aponogeton madagascariensis) is well suited for the in vivo study of developmental PCD. Live streaming video and quantitative analysis, coupled with transmission electron microscopy, were used to better understand the PCD sequence, with an emphasis on the chloroplasts. Dividing, dumbbell‐shaped chloroplasts persisted until the late stages of PCD. However, the average size and number of chloroplasts, and the starch granules associated with them, declined steadily in a manner reminiscent of leaf senescence, but distinct from PCD described in the Zinnia tracheary element system. Remaining chloroplasts often formed a ring around the nucleus. Transvacuolar strands, which appeared to be associated with chloroplast transport, first increased and then decreased. Mitochondrial streaming ceased abruptly during the late stages of PCD, apparently due to tonoplast rupture. This rupture occurred shortly before the rapid degradation of the nucleus and plasma membrane collapse, in a manner also reminiscent of the Zinnia model. The presence of numerous objects in the vacuoles suggests increased macro‐autophagy before cell death. These objects were rarely observed in cells not undergoing PCD.
Unsanctioned aggression in rugby union: relationships among aggressiveness, anger, athletic identity, and professionalization
Authors: Maxwell J. P. , Visek A. J.
Published: March 2009

Aggressive players who intentionally cause injury to their opponents are common in many sports, particularly collision sports such as Rugby Union. Although some acts of aggression fall within the rules (sanctioned), others do not (unsanctioned), with the latter tending to be less acceptable than the former. This study attempts to identify characteristics of players who are more likely to employ unsanctioned methods in order to injure an opponent. Male Rugby Union players completed questionnaires assessing aggressiveness, anger, past aggression, professionalization, and athletic identity. Players were assigned to one of two groups based on self‐reported past unsanctioned aggression. Results indicated that demographic variables (e.g., age, playing position, or level of play) were not predictive of group membership. Measures of aggressiveness and professionalization were significant predictors; high scores on both indicated a greater probability of reporting the use of unsanctioned aggressive force for the sole purpose of causing injury or pain. In addition, players who had been taught how to execute aggressive illegal plays without detection were also more likely to report using excessive force to injure an opponent. Results provide further support that highly professionalized players may be more likely to use methods outside the constitutive rules of Rugby Union in order to intentionally injure their opponents. Results are discussed within the context of the increasing win‐at‐all‐cost attitude that is becoming more prevalent in sport and its implications for youth athletes. Aggr. Behav. 35:237–243, 2009. © 2009 Wiley‐Liss, Inc.
Identity issues in building an ESL community: The Puerto Rican experience
Authors: Morales Betsy , Blau Eileen K.
Published: March 2009

English has a unique status in Puerto Rico, giving rise to special challenges in building community and teaching English as a second language on the island. Identity is at the core of these issues.
Community in a hurry: Social contracts and social covenants in short‐term ESL courses
Authors: Martinsen Rob A.
Published: March 2009

This chapter provides an in‐depth look at the nature of community building in short‐term ESL courses. Examples of classroom practices are provided.
Complexity and community: Finding what works in workplace ESL
Authors: Brooks Ann K.
Published: March 2009

This chapter addresses the complexity of providing workplace ESL by identifying patterns of “best practices” in the related fields of human resource management, adult education, and training and development, all of which have a stake in workplace ESL and the integration of immigrant workers.
Children's memory for the duration of a paediatric consultation
Authors: Friedman William J. , Cederborg Ann‐Christin , Hultman Elin , Änghagen Olov , Magnusson Karin Fälth
Published: March 2009

To learn about children's ability to estimate the duration of an event many days after it occurred, 6–12‐year‐old children were asked to judge the amount of time (range 5–45 minutes) they spent in the treatment room as part of a paediatric visit. Judgements were made 1 week or 1 month after the visit occurred. Children showed an average error of about 13 minutes. Retention interval did not significantly affect estimates. Other judgements of the length of the interview itself (mean length 8 minutes) provided what may be the first data on children's ability to make immediate retrospective duration estimates. The results also include information about children's capacity to judge how long ago they visited the clinic. Copyright © 2009 John Wiley & Sons, Ltd.
Microcontact Printing: Limitations and Achievements
Authors: Perl András , Reinhoudt David N. , Huskens Jurriaan
Published: March 2009

Microcontact printing (µCP) offers a simple and low‐cost surface patterning methodology with high versatility and sub‐micrometer accuracy. The process has undergone a spectacular evolution since its invention, improving its capability to form sub‐100 nm SAM patterns of various polar and apolar materials and biomolecules over macroscopic areas. Diverse development lines of µCP are discussed in this work detailing various printing strategies. New printing schemes with improved stamp materials render µCP a reproducible surface‐patterning technique with an increased pattern resolution. New stamp materials and PDMS surface‐treatment methods allow the use of polar molecules as inks. Flat elastomeric surfaces and low‐diffusive inks push the feature sizes to the nanometer range. Chemical and supramolecular interactions between the ink and the substrate increase the applicability of the µCP process.
Effect of input excitation on the quality of empirical dynamic models for type 1 diabetes
Authors: Finan Daniel A. , Palerm Cesar C. , Doyle Francis J. , Seborg Dale E. , Zisser Howard , Bevier Wendy C. , Jovanovič Lois
Published: March 2009

Accurate prediction of future blood glucose trends has the potential to significantly improve glycemic regulation in type 1 diabetes patients. A model‐based controller for an artificial β‐cell, for example, would determine the most efficacious insulin dose for the current sampling interval given available input–output data and model predictions of the resultant glucose trajectory. The two inputs most influential to the glucose concentration are bolused insulin and meal carbohydrates, which in practice are often taken simultaneously and in a specified ratio. This linear dependence has adverse effects on the quality of linear dynamic models identified from such data. On the other hand, inputs with greater degrees of excitation may force the subject into extreme hypoglycemia or hyperglycemia, and thus may be clinically unacceptable. Inputs with good excitation that do not endanger the subject are shown to result in models that can predict glucose trends reasonably accurately, 1–2 h ahead. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Dispersed oil–water–gas flow through a horizontal pipe
Authors: Piela K. , Delfos R. , Ooms G. , Westerweel J. , Oliemans R.V.A.
Published: March 2009

An experimental study of three‐phase dispersed flow in a horizontal pipe has been carried out. The pressure drop over the pipe strongly increases with increasing bubble and drop volume fraction. Because of the presence of drops the transition from dispersed bubble flow to elongated bubble flow occurs at a lower gas volume fraction. The gas bubbles have no significant influence on the phase inversion process. However, phase inversion has a strong effect on the gas bubbles. Just before inversion large bubbles are present and the flow pattern is elongated bubble flow. During the inversion process the bubbles break‐up quickly and as the dispersed drop volume fraction after inversion is much lower than before inversion, a dispersed bubble flow is present after inversion. (When inversion is postponed to high dispersed phase fractions, the volume fraction of the dispersed phase can be as high as 0.9 before inversion and as low as 0.1 after inversion.) © 2009 American Institute of Chemical Engineers AIChE J, 2009
Maturity‐related differences in physical activity among 10‐ to 12‐year‐old girls
Authors: Drenowatz Clemens , Eisenmann Joey C. , Pfeiffer Karin A. , Wickel Eric E. , Gentile Douglas , Walsh David
Published: March 2009

Besides environmental and psycho‐social factors explaining the variation in physical activity levels during adolescence, some evidence suggests that biological processes are involved in regulating habitual daily physical activity and energy expenditure. The purpose of this study was to examine the influence of biological maturity status on physical activity. Chronological age, standing height, sitting height, and body mass were measured cross‐sectionally in 268 girls, aged 9.5 to 11.5 years. Biological maturity groups (Early, Average, Late) were created according to estimated age at peak‐height‐velocity (estAPHV). Habitual physical activity was determined with a pedometer (Yamax Digiwalker SW‐200) over a 7‐day period. Differences in steps/day across maturity groups were examined by ANCOVA, controlling separately for time the pedometer was worn, leg length, and body mass. Mean pedometer steps/day was 10,822 ± 2,639. As expected, body size varied by maturity status (e.g., early > average > late). Significant maturity group differences were found with early maturing girls showing lower activity levels compared to average or late maturers. These differences remained after controlling for time the pedometer was worn and leg length; however, the differences were no longer significant when controlling for body mass. The results suggest that biological maturity status influences physical activity levels in girls between 10 and 12 years of age but the relationship is not independent of body mass. Further research is needed to establish the complex inter‐relationships among adiposity, biological maturation, and energy expenditure during puberty. Am. J. Hum. Biol., 2010. © 2009 Wiley‐Liss, Inc.
Frequency of work‐related respiratory symptoms in workers without asthma
Authors: Chiry Samah , Boulet Louis‐Philippe , Lepage Johanne , Forget Amélie , Bégin Denis , Chaboillez Simone , Malo Jean‐Luc , Gérin Michel , Lemiere Catherine
Published: March 2009

Background

Clinicians are faced with subjects complaining of work‐related respiratory symptoms (WRS) without any evidence of asthma. We sought to assess the prevalence of subjects with WRS without asthma in a cohort of workers referred for possible work‐related asthma (WRA) as well as compare the characteristics and the work environment of subjects with WRS to subjects with WRA.

Methods

A prospective observational study of workers referred for possible WRA over a 1‐year period. Detailed medical and occupational questionnaires were administered. Pulmonary function tests as well as specific‐inhalation challenges were performed.

Results

One hundred twenty workers were investigated. Fifty‐one had WRA while 69 had WRS. The type and the severity of the respiratory symptoms were similar in both groups, except for wheezing which was more frequently reported in subjects with WRA (32 (62.7%)) than in subjects with WRS (16 (23.2%)) (P < 0.01). Both the workers with WRS and WRA were mainly employed in the manufacturing sector (64.7% (WRA) and 71% (WRS)). At the time of the first assessment 64.7% of subjects with WRA and 56.5% with WRS had left their workplace because of their bothersome respiratory symptoms.

Conclusions

Subjects with WRS without asthma represent a large proportion of the subjects assessed in clinics specialized in the field of WRA. Like subjects with WRA, the population with WRS is likely to represent a significant medical burden. The similarity of the symptoms between the WRA and the WRS groups emphasizes the need to perform a thorough and objective investigation to diagnose WRA. Am. J. Ind. Med. 52:447–454, 2009. © 2009 Wiley‐Liss, Inc.
Linkage disequilibrium mapping of the chromosome 6q21–22.31 bipolar I disorder susceptibility locus
Authors: Fan Jinbo , Ionita‐Laza Iuliana , McQueen Matthew B. , Devlin Bernie , Purcell Shaun , Faraone Stephen V. , Allen Michael H. , Bowden Charles L. , Calabrese Joseph R. , Fossey Mark D. , Friedman Edward S. , Gyulai Laszlo , Hauser Peter , Ketter Terence B. , Marangell Lauren B. , Miklowitz David J. , Nierenberg Andrew A. , Patel Jayendra K. , Sachs Gary S. , Thase Michael E. , Molay Francine B. , Escamilla Michael A. , Nimgaonkar Vishwajit L. , Sklar Pamela , Laird Nan M. , Smoller Jordan W.
Published: March 2009

We previously reported genome‐wide significant evidence for linkage between chromosome 6q and bipolar I disorder (BPI) by performing a meta‐analysis of original genotype data from 11 genome scan linkage studies. We now present follow‐up linkage disequilibrium mapping of the linked region utilizing 3,047 single nucleotide polymorphism (SNP) markers in a case–control sample (N = 530 cases, 534 controls) and family‐based sample (N = 256 nuclear families, 1,301 individuals). The strongest single SNP result (rs6938431, P = 6.72 × 10−5) was observed in the case–control sample, near the solute carrier family 22, member 16 gene (SLC22A16). In a replication study, we genotyped 151 SNPs in an independent sample (N = 622 cases, 1,181 controls) and observed further evidence of association between variants at SLC22A16 and BPI. Although consistent evidence of association with any single variant was not seen across samples, SNP‐wise and gene‐based test results in the three samples provided convergent evidence for association with SLC22A16, a carnitine transporter, implicating this gene as a novel candidate for BPI risk. Further studies in larger samples are warranted to clarify which, if any, genes in the 6q region confer risk for bipolar disorder. © 2009 Wiley‐Liss, Inc.
Genetic polymorphisms in the DRD2, DRD3, and SLC6A3 gene in elderly patients with delirium
Authors: van Munster Barbara C. , Yazdanpanah Mojgan , Tanck Michael W.T. , de Rooij Sophia E.J.A. , van de Giessen Elsmarieke , Sijbrands Eric J.G. , Zwinderman Aeilko H. , Korevaar Johanna C.
Published: March 2009

Dopamine excess appears to be critical in the final common pathway of delirium. The aim of this study was to investigate whether genetic polymorphisms in three dopamine‐related genes (the dopamine receptor 2 (DRD2), dopamine receptor 3 (DRD3), and the dopamine transporter (SLC6A3) gene) were associated with delirium. Patients aged 65 years and older acutely admitted to the medical department or to the surgical department following hip fracture were included. Delirium was diagnosed by the Confusion Assessment Method. Sixteen single nucleotide polymorphisms (SNPs) and one variable number of tandem repeats in the SLC6A3 gene, nine SNPs in the DRD2 gene, and six SNPs in the DRD3 gene were genotyped. Fifty percent of the 115 surgical patients and 34% of the 605 medical patients experienced delirium. Delirious patients were older and had more frequently pre‐existing functional and cognitive impairment (P < 0.001). After correction for multiple testing, one SNP in the SLC6A3 gene (rs393795) was associated with reduced risk of delirium (P = 0.032). Adjusted for age, cognitive impairment, and functional impairment, three SNPs in the DRD2 gene and seven SNPs in the SLC6A3 gene were associated with delirium; none of these associations was significant after correction for multiple testing. Variations in the SLC6A3 gene and possibly the DRD2 gene were associated with delirium. Although validation of these results is needed our results support a role for the dopamine transporter and dopamine receptor 2 in the pathogenesis of delirium. © 2009 Wiley‐Liss, Inc.
A broad spectrum of developmental delay in a large cohort of prolidase deficiency patients demonstrates marked interfamilial and intrafamilial phenotypic variability
Authors: Falik‐Zaccai Tzipora C. , Khayat Morad , Luder Anthony , Frenkel Pnina , Magen Daniella , Brik Riva , Gershoni‐Baruch Ruth , Mandel Hanna
Published: March 2009

Prolidase deficiency (PD) is a rare, pan‐ethnic, autosomal recessive disease with a broad phenotypic spectrum. Seventeen causative mutations in the PEPD gene have been reported worldwide. The purpose of this study is to characterize, clinically and molecularly, 20 prolidase deficient patients of Arab Moslem and Druze origin from 10 kindreds residing in northern Israel. All PD patients manifested developmental delay and facial dysmorphism. Typical PD dermatological symptoms, splenomegaly, and recurrent respiratory infections presented in varying degrees. Two patients had systemic lupus erythematosus (SLE), and one a novel cystic fibrosis phenotype. Direct DNA sequencing revealed two novel missense mutations, A212P and L368R. In addition, a previously reported S202F mutation was detected in 17 patients from seven Druze and three Arab Moslem kindreds. Patients homozygous for the S202F mutation manifest considerable interfamilial and intrafamilial phenotypic variability. The high prevalence of this mutation among Arab Moslems and Druze residing in northern Israel, and the presence of an identical haplotype along 500,000 bp in patients and their parents, suggests a founder event tracing back to before the breakaway of the Druze from mainstream Moslem society. © 2009 Wiley‐Liss, Inc.
COMT val158met influence on electroconvulsive therapy response in major depression
Authors: Domschke Katharina , Zavorotnyy Maxim , Diemer Julia , Nitsche Sarina , Hohoff Christa , Baune Bernhard T. , Deckert Juergen , Arolt Volker , Zwanzger Peter
Published: March 2009

There is strong evidence for a genetic contribution to the pathogenesis of depression, with the functional catechol‐O‐methyltransferase (COMT) val158met polymorphism having been suggested as a potential susceptibility factor. In the present study, the effect of COMT val158met on response to electroconvulsive therapy (ECT) was analyzed in a sample of 104 Caucasian patients (f = 71, m = 33) with pharmacologically treatment‐resistant Major Depression. The higher active COMT 158val allele was found to be associated with (1) higher pre‐ECT severity of depression and (2) better treatment response to ECT particularly regarding the core symptoms of depression as well as sleep‐related symptoms. These findings were restricted to the female subgroup of patients. In summary, the present study supports a potentially gender‐specific significant impact of COMT gene variation on electroconvulsive therapy response, with COMT 158val risk allele carriers suffering from more severe, pharmacologically less efficiently treatable depression and thus possibly deriving greater benefit from ECT in the first place. © 2009 Wiley‐Liss, Inc.
An association study of common variation at the MAPT locus with late‐onset Alzheimer's disease
Authors: Abraham Richard , Sims Rebecca , Carroll Liam , Hollingworth Paul , O'Donovan Michael C. , Williams Julie , Owen Michael J.
Published: March 2009

The MAPT gene that encodes Tau is located on chromosome 17q21, in a region, which has evolved to form two major haplotypes, H1 and H2. There is strong evidence that the H1 haplotype, and a sub‐haplotype (H1C), are overrepresented and associated with increased risk for the sporadic tauopathies, progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Both PSP and CBD cases display Tau pathology similar to Late‐Onset Alzheimer's Disease (LOAD). However, numerous association studies investigating the genetic involvement of MAPT in LOAD have generated conflicting results. Here we have used a large LOAD case–control sample to genotype SNPs that have been shown to define H1/H2 status and intra‐H1 variability. Single marker association analyses found no evidence that any of the SNPs are associated with risk of LOAD. When gender and APOE4 status were taken into account we observed suggestive association for SNP rs242557 (P = 0.02). Stratification of the sample revealed association with rs242557 only in APOE4 positive individuals (P = 0.01 recessive model), however this result would not survive multiple correction. There was no significant difference in H1/H2 haplotype distribution between cases and controls. We also tested the association of specific sub‐haplotypes on the H1 background and likewise results were negative. No effect was observed on disease age of onset for any of the markers studied. In summary, we find no evidence for allelic or haplotypic association, with SNPs in the MAPT gene and LOAD. SNP rs242557 is nominally significant in the APOE4 positive individuals. None of the SNPs studied modified AAO for LOAD. © 2009 Wiley‐Liss, Inc.
Radiation damage increases Purkinje neuron heterokaryons in neonatal cerebellum
Authors: Espejel Silvia , Romero Ricardo , Alvarez‐Buylla Arturo
Published: March 2009

Objective

Recent studies have shown that in radiated and bone marrow transplanted mice, bone marrow‐derived cells (BMDCs) fuse with Purkinje neurons resulting in the formation of binucleated heterokaryons. Here we investigated whether radiation plays a role in the formation of Purkinje neuron heterokaryons.

Methods

Fused cells were identified by reporter gene expression in mice, carrying floxed LacZ (R26R‐LacZ) in all cells and Cre in hematopoietic‐derived cells. Cell fusion was confirmed by the presence of two nuclei. The number of fused Purkinje neurons was studied in: 1) whole‐body radiated newborn and adult R26R‐LacZ mice, transplanted with bone marrow cells expressing Cre; 2) in newborn and adult mice that received different doses of radiation to the head; and 3) in radiated and non‐radiated newborns treated with a myeloablative drug before bone marrow transplantation.

Results

In neonatal, but not in adult cerebelleum, radiation—in a dose‐dependent manner—induces a dramatic increase in the number of fused Purkinje neurons.

Interpretation

Increase recruitment of BMDCs into the cerebellum, radiation damage to cerebellar cells, or both, increase the formation of fused Purkinje cells. BMDC‐Purkinje heterokaryons formation may reflect an endogeneous neuronal repair mechanism, or it could be a by‐product of radiation‐induced inflammation. In either case, fused Purkinje neurons increase following radiation damage in the developing cerebellum. The above observations reveal a novel consequence of head radiation in neonatal rodents. It will be interesting to determine if similar increase in the number of binucleated Purkinje neurons, occurs in children that receive radiation during early development. Ann Neurol 2009;66:100–109
White matter lesions volume and motor performances in the elderly
Authors: Soumaré Aïcha , Elbaz Alexis , Zhu Yicheng , Maillard Pauline , Crivello Fabrice , Tavernier Béatrice , Dufouil Carole , Mazoyer Bernard , Tzourio Christophe
Published: March 2009

Objectives

To investigate the cross‐sectional and longitudinal associations between performance‐based measures of motor function and volume of white matter lesions (WMLs), and to examine the influence of the localization of these lesions.

Methods

At baseline, motor performances (maximum walking speed, Tinetti gait and balance subscales) were assessed in 1,702 subjects aged 80 years or younger from the Dijon (France), France center of the Three‐City study. Volumes of WMLs lesions (total, periventricular, deep) were measured using an automated method of tissue segmentation and quantification of lesion size. At 8‐year follow‐up, walking speed was evaluated in 1,086 subjects.

Results

At baseline, mean and 95% confidence interval (CI) walking speed was lower in subjects with total volumes of WMLs ≥90th percentile (1.50 [1.45–1.55] m/s) than in subjects with lower volumes (1.56 [1.55–1.58] m/s; p = 0.004). Baseline total volumes of WMLs above the 90th percentile predicted walking speed decline during follow‐up (odds ratio [95% CI] for having the greatest walking speed decline = 2.3 [1.3–4.1], p = 0.006). Moreover, high volumes of periventricular but not deep WMLs were associated with slower walking speed at baseline (p = 0.005) and over time (p = 0.001), and with lower Tinetti gait subscore (p = 0.02).

Interpretation

Our study shows a cross‐sectional and longitudinal association between high total volumes of WMLs, in particular volumes above the 90th percentile, and impaired mobility. These associations were independent of several confounders, including cognition, and were mainly accounted for by volumes of periventricular WMLs. These findings support the hypothesis of a vascular contribution to motor decline in the elderly. Ann Neurol 2009;65:706–715
Pivotal studies of orphan drugs approved for neurological diseases
Authors: Mitsumoto Jun , Dorsey E. Ray , Beck Christopher A. , Kieburtz Karl , Griggs Robert C.
Published: March 2009

Objective

To identify design elements of clinical trials leading to US Food and Drug Administration approval of drugs for neurological diseases with and without orphan indications.

Methods

We used publicly available information to identify approvals for drugs for neurological diseases with an orphan indication (n = 19) and compared them with recent approvals for drugs for neurological diseases without an orphan indication (n = 20). We identified “pivotal trials” from drug labels and drug approval packages, and assessed them on four elements of clinical trial design: control, blinding, randomization, and size.

Results

All drugs for neurological diseases (100%) approved without an orphan indication included at least two randomized, double‐blind, placebo‐controlled trials. In comparison, 32% of drugs with an orphan indication had at least two such trials (p < 0.001) and 74% had at least one (p = 0.02). Thirty‐three pivotal trials were conducted for the 19 drugs approved with an orphan indication. Of the 33 trials, 11 (33%) did not use a placebo control, 9 (27%) were not double blind, and 4 (12%) were not randomized. Drugs approved without an orphan indication had more pivotal trials per drug (3.8 vs 1.7 trials; p < 0.001) and a larger mean trial size (506 vs 164 trial participants; p < 0.001).

Interpretation

The US Food and Drug Administration has approved orphan drugs for neurological diseases without randomized, doubled‐blind, placebo‐controlled pivotal trials. As orphan drug development grows, demand will likely increase for alternative designs for conducting adequate and well‐controlled studies to demonstrate drug efficacy. Ann Neurol 2009;66:184–190
Mild cognitive impairment in rapid eye movement sleep behavior disorder and Parkinson's disease
Authors: Gagnon Jean‐François , Vendette Mélanie , Postuma Ronald B. , Desjardins Catherine , Massicotte‐Marquez Jessica , Panisset Michel , Montplaisir Jacques
Published: March 2009

Objective

To investigate the frequency and subtypes of mild cognitive impairment (MCI) in idiopathic rapid eye movement sleep behavior disorder (RBD) and Parkinson's disease (PD) in association with RBD.

Methods

One hundred and twelve subjects without dementia or major depression including 32 idiopathic RBD patients, 22 PD patients with polysomnography‐confirmed RBD, 18 PD patients without RBD, and 40 healthy control subjects, underwent a comprehensive neuropsychological evaluation. We compared the proportion of patients with MCI between groups using standard diagnostic criteria.

Results

MCI was found in 50% of idiopathic RBD patients and 73% of PD patients with RBD. In contrast, only 11% of PD patients without RBD and 8% of control subjects had MCI. The presence of MCI was significantly greater in idiopathic RBD patients and PD patients with RBD than in PD patients without RBD and control subjects. PD patients with RBD also performed worse than idiopathic RBD patients on neuropsychological tests assessing visuoconstructional and visuoperceptual abilities.

Interpretation

In both its association with PD and its idiopathic form, RBD is an important risk factor for MCI. Except for visuoconstructional and visuoperceptual problems, RBD may be an important determinant of cognitive impairment in PD. Ann Neurol 2009;66:39–47
Solution Structure of a Locked Nucleic Acid Modified Quadruplex: Introducing the V4 Folding Topology
Authors: Nielsen Jakob T. , Arar Khalil , Petersen Michael
Published: March 2009

Scharfe Kurven: Die Struktur einer Telomersequenz aus Oxytricha nova, die mit einer konformativ festgelegten Nucleinsäure modifiziert wurde, unterscheidet sich durch ihre bemerkenswerte Faltung vom nativen O.‐nova‐Quadruplex. Jeder Guaninabschnitt bildet eine V‐Kurve, sodass der erste und vierte Guaninrest in derselben Tetrade liegen. Über den Tetraden ist das DNA‐Rückgrat scharf gekrümmt. Die Topologie wird durch ein Wechselspiel von Sequenz und Konformation definiert.

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Auf dem Weg zum integrierten chemischen Schaltkreis
Authors: Belder Detlev
Published: March 2009

Alles auf einem Chip: Aktuelle Entwicklungen in der Mikrofluidik machen es möglich, zwei Mikrofluidikbereiche – Mikrofluidik mit Tropfen und kontinuierliche Systeme – zu verbinden (siehe Bild). Dadurch rückt die Realisierung integrierter, komplexer Synthese‐ und Analyselabors auf einem Chip in greifbare Nähe; z. B. könnte man nach dem Baukastenprinzip mehrstufige Reaktionen zusammen mit Reinigung und Analytik auf einem Chip integrieren.

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Spinpolarisierte Strukturen und Festkörper‐NMR‐Spektroskopie paramagnetischer Verbindungen
Authors: Schmedt auf der Günne Jörn
Published: March 2009

Informationen über elektronische Spindichten und Kopplungsmechanismen paramagnetischer Verbindungen lassen sich mit hoher Empfindlichkeit und atomarer Auflösung durch Festkörper‐NMR‐Spektroskopie erhalten. Das Bild zeigt, wie die Hyperfeinaufspaltung durch Relaxation kollabiert. Welche Proben sind geeignet, welche Näherungen müssen gemacht werden?

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Fehlerkorrektur während der Proteinbiosynthese
Authors: Sprinzl Mathias
Published: March 2009

Korrigiert und aussortiert: Der Einbau einer falschen Aminosäure in eine wachsende Polypeptidkette führt zu einem Korrekturschritt, während dessen der Terminationsfaktor (RF1) das Peptid von der falsch gebundenen Peptidyl‐tRNA hydrolysiert (siehe Bild). Das fehlerhafte entstehende Polypeptid wird vom Ribosom freigesetzt und abgebaut.

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Biotin–Avidin as a Protease‐Responsive Cap System for Controlled Guest Release from Colloidal Mesoporous Silica
Authors: Schlossbauer Axel , Kecht Johann , Bein Thomas
Published: March 2009

Tell your guests when it's time to go: When avidin caps are attached to biotinylated colloidal mesoporous silica, the four subunits of the protein avidin can each bind to a biotin moiety attached to the surface (see picture). The resulting material is a promising candidate for the design of smart detergents or drug‐delivery systems. The caps can be opened to release guest molecules by controlled enzymatic hydrolysis of the protein.

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Solution‐Based Direct Growth of Organic Crystals on an Active Channel Region for Printable Bottom‐Contact Organic Field‐Effect Transistors
Authors: Hong Jung‐Pyo , Lee Seonghoon
Published: March 2009

The growth and self‐organization of organic crystals between a source (S) and drain (D) electrode by a method based on the use of a micropipette and isothermal evaporation of the solvent in a two‐liquid system led to the formation of organic‐crystal transistors (see polarized optical micrograph). The method is similar to ink‐jet printing and should be suitable for the fabrication of low‐cost and mass‐producible printed electronic devices.

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Hydrogen Bonding in Protic Ionic Liquids: Reminiscent of Water
Authors: Fumino Koichi , Wulf Alexander , Ludwig Ralf
Published: March 2009

Similarities and differences: Far‐infrared spectra of protic ionic liquids could be assigned to intermolecular bending and stretching modes of hydrogen bonds. The characteristics of the low‐frequency spectra resemble those of water. Both liquids form three‐dimensional network structures, but only water is capable of building tetrahedral configurations. EAN: ethylammonium nitrate, PAN: propylammonium nitrate, DMAN: dimethylammonium nitrate.

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Solution Structure of a Locked Nucleic Acid Modified Quadruplex: Introducing the V4 Folding Topology
Authors: Nielsen Jakob T. , Arar Khalil , Petersen Michael
Published: March 2009

Sharp curves: The structure of a locked nucleic acid modified telomeric sequence from Oxytricha nova displays a remarkable folding topology, distinct from the native O. nova quadruplex. Each guanine stretch folds back in a V‐shaped turn that puts the first and fourth guanines in the same tetrad, looping over a tetrad with a sharp turn in the DNA backbone, showing how subtle interplay between sequence and conformation defines the folding topology.

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Palladium‐Catalyzed Oxidative Intermolecular Difunctionalization of Terminal Alkenes with Organostannanes and Molecular Oxygen
Authors: Urkalan Kaveri Balan , Sigman Matthew S.
Published: March 2009

A cationic palladium complexcatalyzes the title transformations, which are thought to proceed via a π‐allyl or π‐benzyl intermediate. The regioselectivity of the reaction (1,2‐ or 1,1‐difunctionalization) depends on the type of terminal double bond (conjugated or nonconjugated) in the substrate (see scheme) and appears to be controlled by the relative rates of β‐hydride elimination and transmetalation. DMA=dimethylacetamide, Tf=triflyl.

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Supramolecular Chiral Transcription and Recognition by Mesoporous Silica Prepared by Chiral Imprinting of a Helical Micelle
Authors: Qiu Huibin , Inoue Yoshihisa , Che Shunai
Published: March 2009

Let′s twist again: The chirality of a helical propeller‐like micelle has been memorized by functional groups on the mesopore surface of chiral mesoporous silicas. Such imprinted supramolecular chirality can be transcripted to poly(propiolic acid) sodium salt and tetraphenylporphine tetrasulfonic acid (see picture), and recognized by B‐DNA.

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Spin‐Polarized Structures and Solid‐State NMR Spectroscopy of Paramagnetic Compounds
Authors: Schmedt auf der Günne Jörn
Published: March 2009

On an atomic scale and with high sensitivity, solid‐state NMR spectroscopy can provide information about the electronic spin density and coupling mechanisms in paramagnetic compounds. The picture shows how the hyperfine splitting collapses through relaxation. Insights into which compounds are suitable and which approximations have to be made are given.

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Synthesis of new phase transfer‐catalyzed free radical polymerization of ethyl methacrylate: A kinetic study
Authors: Sivapitchai Savitha , Umapathy M. J.
Published: March 2009

In this study, a new phase transfer catalyst has been synthesized and characterized, which is used for the study of kinetics and mechanism of the free radical polymerization of ethyl methacrylate. The reactions were carried out using peroxodisulfate as initiator in inert and unstirred condition at 60°C ± 1°C. The order with respect to monomer, initiator, and catalyst were found to be 1, 0.7, and 0.5, respectively. The rate of polymerization is independent of ionic strength and pH. Based on the results obtained, a mechanism has been proposed for the polymerization reactions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Viscoelastic behavior and submolecular level dynamic heterogeneity of hydrogen‐bonded polymer blends probed by dynamic FTIR spectroscopy
Authors: Huang He , Liu Qiong , Sun Tai , Chen Jun , Guo Wenjuan
Published: March 2009

Viscoelastic behavior and submolecular (functional group) level dynamic heterogeneity of hydrogen‐bonded poly(vinyl phenol)/poly(methyl acrylate) (PVPh/PMA) blends were investigated by using dynamic FTIR spectroscopy. It has been found that the viscoelastic behaviors of the blends, measured by the dynamic (in‐phase and quadrature) spectra of both “free” and hydrogen‐bonded carbonyl groups are dependent on the compositions, i.e., the Tg of the blends, and the degree of hydrogen bonding between the two components. In all the blends studied, elastic response of the hydrogen‐bonded carbonyl groups to the applied strain has been found. The free carbonyl groups respond differently to the applied strain in these blends. Essentially, elastic response of the free carbonyl groups to the applied strain is observed in blends with both a high Tg and a higher fraction (∼ 40%) of intermolecular hydrogen bonding between PVPh and PMA, and the submolecular level dynamic heterogeneity is suppressed. The free carbonyl group has a viscous component to its response, in blends having a lower fraction (∼ 20%) of hydrogen bonds, even at temperatures well below the thermal Tg of the blends, suggesting that there is a degree of submolecular level dynamic heterogeneity in these blends. Almost entirely viscous response of the free carbonyl group is found in blends whose Tg is close to room temperature and fraction of PVPh/PMA hydrogen bonds is very low. The results reported here suggest that dynamic FTIR has considerable potential for studying specific interactions and viscoelastic behaviors in hydrogen‐bonded polymer blends on submolecular level. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Trade‐off between immune stimulation and expression of storage protein genes
Authors: Lourenço Anete P. , Martins Juliana R. , Bitondi Márcia M.G. , Simões Zilá L.P.
Published: March 2009

Proteins stored in insect hemolymph may serve as a source of amino acids and energy for metabolism and development. The expression of the main storage proteins was assessed in bacterial‐challenged honey bees using real‐time (RT)‐PCR and Western blot. After ensuring that the immune system had been activated by measuring the ensuing expression of the innate immune response genes, defensin‐1 (def‐1) and prophenoloxidase (proPO), we verified the expression of four genes encoding storage proteins. The levels of vitellogenin (vg) mRNA and of the respective protein were significantly lowered in bees injected with bacteria or water only (injury). An equivalent response was observed in orally‐infected bees. The levels of apolipophorin II/I (apoLp‐II/I) and hexamerin (hex 70a) mRNAs did not significantly change, but levels of Hex 70a protein subunit showed a substantial decay after bacterial challenge or injury. Infection also caused a strong reduction in the levels of apoLp‐III transcripts. Our findings are consistent with a down‐regulation of the expression and accumulation of storage proteins as a consequence of activation of the immune system, suggesting that this phenomenon represents a strategy to redirect resources to combat injury or infection. © 2009 Wiley Periodicals, Inc.
Validation of psychometric research instruments: The case of information science
Authors: Kim Yong‐Mi
Published: March 2009

Instrument validation is a critical step that researchers should employ in order to ensure the generation of scientifically valid knowledge. Without it, the basis of research findings and the generalization of such are threatened. This is especially true in the social sciences, a discipline in which the majority of published articles utilize subjective instruments in the collection of data. Consequently, instrument validation has increasingly become common practice in the social sciences, yet implementation of this practice differs greatly among the social‐science disciplines. The assessment of instrument validation undertaken in this study attempts to provide guidance for reviewers, editors, authors, and readers, by offering various techniques of validity and analyzing the quality of a set of psychometric journal articles. In this research, six attributes of instrument validation areas are identified as validation protocol. The Journal of the American Society for Information Science and Technology (JASIST), which is widely recognized as a leading journal in the field of information science, was selected for examination to determine how well a set of research articles ranked in meeting instrument‐validation protocol. Findings show that while researchers are becoming increasingly attentive to certain validation issues, standards on validation processes and reporting might prove helpful. This paper identifies areas for improvement in the reporting of validity measures and offers ways for researchers to implement them.