bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factor Analysis for Ranked Data with Application to a Job Selection Attitude Survey
Authors: Yu Philip L. H. , Lam K. F. , Lo S. M. 
Published: June 2005

SummaryFactor analysis is a powerful tool to identify the common characteristics among a set of variables that are measured on a continuous scale. In the context of factor analysis for non-continuous-type data, most applications are restricted to item response data only. We extend the factor model to accommodate ranked data. The Monte Carlo expectation–maximization algorithm is used for parameter estimation at which the E-step is implemented via the Gibbs sampler. An analysis based on both complete and incomplete ranked data (e.g. rank the top q out of k items) is considered. Estimation of the factor scores is also discussed. The method proposed is applied to analyse a set of incomplete ranked data that were obtained from a survey that was carried out in GuangZhou, a major city in mainland China, to investigate the factors affecting people's attitude towards choosing jobs.
Transcript profiling of Eucalyptus xylem genes during tension wood formation
Authors: Paux Etienne , Carocha Víctor , Marques Cristina , Mendes de Sousa António , Borralho Nuno , Sivadon Pierre , Grima‐Pettenati Jacqueline 
Published: June 2005

Summary

Tension wood formed in response to gravitational force is a striking example of the plasticity of angiosperm wood. In this study our goal was to characterize the early changes in gene expression during tension wood formation in Eucalyptus.
Using cDNA array technology, transcript profiling of 231 genes preferentially expressed in differentiating Eucalyptus xylem was followed from 6 h to 1 wk of a tension time course of artificially bent Eucalyptus trees.
196 genes were differentially regulated between control and bent trees, some exhibiting distinctive expression patterns related to changes in secondary cell wall structure and composition. For instance, expression of a cellulose synthase gene was well correlated with the appearance of the G‐layers. Cluster correlation analysis revealed differential regulation of lignin biosynthetic genes and may also be used to help infer the function of unknown gene products.
Eucalyptus wood transcriptome analysis during tension wood formation not only provided new clues into the transcriptional regulatory network of genes preferentially expressed in xylem, but also highlighted candidate genes responsible for the genetic and environmentally induced variation of wood quality traits.
Short‐term physiological and developmental responses to nitrogen availability in hybrid poplar
Authors: Cooke Janice E. K. , Martin Timothy A. , Davis John M. 
Published: June 2005

Summary

Nitrogen fertilization induces dramatic changes in the growth and development of plants, including forest trees. In this study we examined short‐term responses of hybrid poplar, Populus balsamifera ssp. trichocarpa × deltoides, to N fertilization.
Glasshouse‐grown saplings subjected to limiting, intermediate, and luxuriant levels of ammonium nitrate over a 28 d time course demonstrated rapid changes to whole‐plant architecture and biomass accumulation. Nitrogen‐associated shifts in allocation occurred in temporally distinct stages. Nitrogen availability modulated parameters that affect carbon gain, including light‐saturated net photosynthesis and leaf area. These parameters were affected by N‐induced changes to leaf maturation and senescence. Leaf area was also affected by N‐induced sylleptic branch development.
Genes encoding vegetative storage proteins and starch biosynthetic enzymes exhibited contrasting patterns of expression under differential N availability. A gene encoding a previously uncharacterized putative pectin methylesterase inhibitor displayed expression patterns comparable to the starch biosynthetic genes.
The results of this study illustrate the phenotypic plasticity that P. balsamifera ssp. trichocarpa × deltoides exhibits in response to differential N availability.
The transcriptome of Populus in elevated CO2
Authors: Taylor Gail , Street Nathaniel R. , Tricker Penny J. , Sjödin Andreas , Graham Laura , Skogström Oskar , Calfapietra Carlo , Scarascia‐Mugnozza Giuseppe , Jansson Stefan 
Published: June 2005

Summary

The consequences of increasing atmospheric carbon dioxide for long‐term adaptation of forest ecosystems remain uncertain, with virtually no studies undertaken at the genetic level. A global analysis using cDNA microarrays was conducted following 6 yr exposure of Populus × euramericana (clone I‐214) to elevated [CO2] in a FACE (free‐air CO2 enrichment) experiment.
Gene expression was sensitive to elevated [CO2] but the response depended on the developmental age of the leaves, and < 50 transcripts differed significantly between different CO2 environments. For young leaves most differentially expressed genes were upregulated in elevated [CO2], while in semimature leaves most were downregulated in elevated [CO2].
For transcripts related only to the small subunit of Rubisco, upregulation in LPI 3 and downregulation in LPI 6 leaves in elevated CO2 was confirmed by anova. Similar patterns of gene expression for young leaves were also confirmed independently across year 3 and year 6 microarray data, and using real‐time RT–PCR.
This study provides the first clues to the long‐term genetic expression changes that may occur during long‐term plant response to elevated CO2.
Does glutathione metabolism have a role in the defence of poplar against zinc excess?
Authors: Di Baccio Daniela , Kopriva Stanislav , Sebastiani Luca , Rennenberg Heinz 
Published: June 2005

Summary

Transition metals such as zinc (Zn) are essential micronutrients for many physiological processes, but they become toxic at elevated levels. Zinc is one of the most abundant trace heavy metals present in agro‐ecosystems.
Populus spp. have been suggested as good candidates for using to study the removal and/or immobilization of environmental organic and inorganic pollutants. In order to understand the physiological and biochemical bases of this assumption for Zn, plants of Populus deltoides × P. nigra (P. × euramericana) were grown in hydroponics with different concentrations of Zn [1 µm (control), and 1, 5 and 10 mm] in the nutrient solution.
Shoot biomass decreased at 5 and 10 mm Zn, while the Zn content of young leaves increased progressively with increasing Zn concentration (1–10 mm). Total glutathione (GSH+GSSG) content was reduced with increasing Zn concentration, while the contribution of oxidized to total glutathione increased. Despite these observations, semiquantitative reverse transcription–polymerase chain reaction (RT–PCR) revealed that the gene expression of GSH reductase (GR, chloroplastic and cytosolic isoform) and γ‐glutamylcysteine synthetase (γ‐ECS) increased in young leaves of poplars treated with excess Zn.
We conclude that GSH synthesis, consumption and redox status play a central role in the response of poplars to high concentrations of Zn.
CFF thresholds: relation to macular pigment optical density
Authors: Hammond Billy R. , Wooten Billy R. 
Published: June 2005

AbstractPurpose:  Only two small studies have evaluated the relation between individual differences in macular pigment (MP) levels and visual health prior to retinal disease. In this study, we assess the relation between MP and a general measure of visual health, the critical flicker fusion (CFF) threshold.Methods:  A total of 134 subjects were assessed. CFF values were determined psychophysically using a 570 nm, circular 1‐degree test field centrally fixated. MP optical density was measured using flicker photometry and a 1‐degree circular 458 nm test field centrally fixated. Personal characteristics were determined by questionnaire.Results:  Similar to past studies, we found a significant decline in CFF values with age (r = −0.56). There was a significant positive relationship (r = 0.30, p < 0.001) between MP density and CFF values that was independent of age.Conclusions:  These results are consistent with a protective effect of MP on visual health across the lifespan.
The effect of apparent depth in pictorial images on accommodation
Authors: Busby Alan , Ciuffreda Kenneth J. 
Published: June 2005

AbstractThe purpose of this study was to investigate the effect of the apparent depth of pictorial images on accommodation. Steady‐state accommodation was assessed objectively while viewing eight pictorial stimuli containing varying degrees of monocular cues to depth. Sixteen young adult subjects were tested monocularly with accommodation either in the closed‐loop or open‐loop mode. Pictorial depth cues significantly influenced the mean level of accommodation under some of the open‐loop conditions in which blur feedback was rendered ineffective. For nearly all stimuli and viewing modes, the mean accommodative responses were biased in the perceptually‐appropriate direction, but they were larger in the open‐loop condition. Apparent depth cues did not significantly affect accommodation under closed‐loop viewing conditions, presumably because blur feedback markedly dampened any perceptually‐driven influences. Consistent with current models of accommodation, and several earlier studies, perceptually‐based accommodation had only a secondary effect on the overall accommodative response level under naturalistic viewing conditions, with blur dominating.
Treating Early Versus Treating Mild: Timing of Migraine Prescription Medications Among Patients With Diagnosed Migraine
Authors: Foley Kathleen A. , Cady Roger , Martin Vincent , Adelman James , Diamond Merle , Bell Christopher F. , Dayno Jeffrey M. , Hu X. Henry 
Published: June 2005

Introduction.—Although research suggests that early treatment of migraine headache when the pain is mild results in better outcomes for patients, many patients delay taking their acute‐migraine medication until their headaches are moderate or severe. Understanding when and why patients use their migraine medications is an important first step to improve migraine management.Methods.—A prospective observational study, conducted at a major national retail pharmacy chain with stores across the United States between April 2001 and November 2002, enrolled men and women between 18 and 55 years of age with a physician diagnosis of migraine with or without aura. Baseline data on 690 patients included patient demographics, migraine history, medication use, tendency to avoid or delay treatment of a migraine attack, and reasons for delaying treatment. Reasons for delaying treatment were assessed via a checklist of nine potential reasons. In the follow‐up survey completed after treatment of the next migraine attack, patients reported the timing of medication use in relation to pain onset and the severity of the migraine headache at the time they took the medication.Results.—Despite the severity of their typical migraine attacks, approximately 49% of the respondents answered, “yes” to the question, “Do you often avoid or delay taking your migraine medications when you start to experience a migraine attack?” The two most common rationales for avoiding or delaying treatment were “wanting to wait and see if it is really a migraine attack” (69%) followed by “only want to take medications if it is a severe attack” (46%). In the follow‐up survey, regardless of medication used, about 85% of patients did not treat their next migraine attack until the headache pain was moderate or severe, although 74% treated within 1 hour of pain onset.Conclusion.—These results suggest that patients with migraine often delay their treatment until they have identified their attack as a migraine. In addition, while many patients treated their follow‐up headache early, they did not treat when the pain was mild. This suggests that there is an opportunity for physicians to educate their migraine patients on how to differentiate migraine from other headache types and about when and how to use their acute‐migraine medication.
Cortical Inhibition Is Reduced in Chronic and Episodic Migraine and Demonstrates a Spectrum of Illness
Authors: Aurora Sheena K. , Barrodale Patricia , Chronicle Edward P. , Mulleners Wim M. 
Published: June 2005

Background.—The pathophysiological relationship between episodic migraine and chronic migraine is not fully understood. We aimed to examine transcranial magnetic stimulation (TMS) indices of cortical excitability in patients with episodic migraine (EM) and probable chronic migraine (PCM), and matched controls.Methods.—Cortical excitability was assessed at baseline with two well‐established methods: phosphene thresholds (PT) and magnetic suppression of perceptual accuracy (MSPA) profiles. Five EM patients, five PCM patients, and five normal controls participated in the main study. In addition, two patients were reassessed after 30 days of treatment with topiramate.Results.—Both PT and MPSA measures were consistent in indicating a continuum of excitability across the three groups: PCM patients had the highest excitability, followed by EM, then controls. In the two treated patients MPSA profiles appeared to normalize at a 100 mg dosage.Conclusions.—Patients with PCM appear to be characterized by very high cortical excitability. This may contribute to their greatly increased attack frequency. TMS‐based methods will be important for future research examining the evolution of chronic migraine from episodic migraine over time.
Patients' Management of Migraine and Chronic Daily Headache: A Study of the Members of the Migraine Action Association (United Kingdom)
Authors: Peters Michele , Abu‐Saad Huda Huijer , Robbins Ian , Vydelingum Vasso , Dowson Andrew , Murphy Margaret 
Published: June 2005

Background.—Many strategies are available to treat and prevent migraine and chronic daily headache (CDH). Broadly these strategies can be divided into four groups, including (i) health care consultations, (ii) medication and alternative remedies, (iii) general (acute and prophylactic) strategies, and (iv) social support.Objective.—This study aimed to compare headache management between migraine (MO), migraine with aura (MA), and those with CDH over the last 12 months.Design.—A postal questionnaire was sent to 887 members of the Migraine Action Association (MAA). The response rate was 60.5% (n = 537), and 438 questionnaires were included in the analysis. Migraine (n = 117) and MA (n = 239) patients were classed according to the International Headache Society (IHS). CDH (n = 82) was diagnosed when respondents had 15 or more headache days per month. Descriptive tests, analysis of variances (ANOVAs), χ2, and Kruskal‐Wallis tests were used for statistical analysis (P < .05).Results.—The three groups did not differ in age, gender, ethnicity, level of education, and employment status. Significant differences in management strategies between the groups were found in the number of respondents who had consulted headache specialists (P= .002) and neurologists (P= .004), the number and types of acute medications (eg, triptans, P= .002), the use of antidepressants (P= .004), and some acute and prophylactic avoidance techniques. Although, no significant differences between the groups were found in the use of other health professionals (eg, GP), alternative health professionals, general acute management, and the use of social support, they all actively used these strategies.Conclusions.—The respondents of this study were active users of management strategies that are based on a combination of health care consultations, medication and alternative remedies, general management, and social support. In comparison to previous findings, the respondents in this study frequently reported higher use of management strategies (such as the use of triptans), which may be related to this group of patients being better informed about headache management than those with headache within the general population. Thus, the findings may not be representative for the general population, but they give an indication of the influence and importance of headache‐related education carried out by patient organizations such as the MAA.
The Classification of Chronic Daily Headache in Adolescents—A Comparison Between the Second Edition of the International Classification of Headache Disorders and Alternative Diagnostic Criteria
Authors: Bigal Marcelo E. , Rapoport Alan M. , Tepper Stewart J. , Sheftell Fred D. , Lipton Richard B. 
Published: June 2005

Objectives.—To compare the second edition of the International Classification of Headache Disorders (ICHD‐2) and the Silberstein‐Lipton (S‐L) criteria in the classification of adolescents with chronic daily headache (CDH).Methods.—We reviewed the clinical records and the headache diaries of 170 adolescents (13 to 17 years) seen between 1998 and 2003 at a headache center. Relevant information was transferred to a standardized form that included operational criteria for the ICHD‐2. CDH subtypes were classified according the criteria proposed by S‐L into transformed migraine (TM) with (TM+) and without medication overuse (TM−), chronic tension‐type headache (CTTH), new daily persistent headache (NDPH), and hemicrania continua (HC).Results.—From the 69 patients with TM− according the S‐L criteria, most (71%) could be classified as chronic migraine (CM), while a minority of patients required a combination of diagnosis, mainly migraine and CTTH (14.4%). Of the patients with TM+, just 39.6% met the criteria for probable CM (PCM) with probable medication overuse (PMO). If instead of 15 migraine days per month, we considered 15 or more days of migraine or probable migraine, 84% of the subjects with TM− and 68.7% of those with TM+ could be classified. Of the 27 subjects classified as NDPH without medication overuse according to the S‐L system, the majority (51.2%) were also classified as NDPH according the ICHD‐2. Interestingly, three (11.1% of the subjects with NDPH without medication overuse) were classified as CM in the ICHD‐2 because these patients had an abrupt onset of 15 or more days of migraine per month. All patients with NDPH with medication overuse according to the S‐L criteria required a combination of diagnoses in the ICHD‐2. All subjects with CTTH received a single diagnosis in both classification systems.Conclusions.—(i) Among adolescents with TM, the majority (58.1%) could be classified as CM, according to the ICHD‐2. These results were driven by TM without medication overuse. (ii) If the ICHD‐2 criteria for CM are revised to require 15 days of migraine or probable migraine, the proportion of patients with TM− who meet the criteria for CM increases from 71% to 84%; for TM+, the proportion with probable chronic migraine and PMO increases from 30% to 68%. (iii) About half of the patients with NDPH according to the S‐L criteria have too many migraine features to meet ICHD‐2 criteria for NDPH.
Gaze Deviation from Contralateral Pseudoperiodic Lateralized Epileptiform Discharges (PLEDs)
Authors: Kaplan Peter W. 
Published: June 2005

Summary:  Pseudoperiodic lateralized epileptiform discharges (PLEDs) usually produce “negative” neurologic findings. This contrasts with seizures which typically induce cortical activation with “positive” clinical manifestations. Gaze preference may arise from ipsilateral frontal eye fields (FEFs) damage because of the unopposed action of an intact contralateral FEF. Epileptic nystagmus (EN) and gaze deviation (GD) can also occur with focal temporo‐parieto‐occipital or hemispheric seizures in awake or obtunded patients.A patient with old right frontal and parieto‐temporal cerebral infarctions manifested leftward gaze preference and deviation (without nystagmus) while alert and talking. Digitized EEG demonstrated PLEDs at ∼1 Hz over the right fronto‐central region, without electrographic seizures.This report illustrates that PLEDs without seizures may excite frontal regions proximate to the FEFs to produce contraversive gaze preference in an awake patient, and discusses putative mechanisms. Gaze deviation, in this case, was the principal clinical feature of PLEDs.
Short‐term Effects of Kainic Acid on CA1 Hippocampal Interneurons Differentially Vulnerable to Excitotoxicity
Authors: Sanon Nathalie , Carmant Lionel , Emond Martine , Congar Patrice , Lacaille Jean‐Claude 
Published: June 2005

Summary:  Purpose: We sought to identify the inhibitory interneurons of the rat hippocampal CA1 region selectively vulnerable in the kainic acid (KA) model of temporal lobe epilepsy and to determine whether their selective vulnerability could be due to differential short‐term KA effects. Methods: We quantified vulnerable interneurons in stratum oriens‐alveus (O/A) by using immunohistochemistry for glutamic acid decarboxylase (GAD), parvalbumin (PV), and somatostatin (SS) after KA injections in rats, and then compared in normal slices the effects of KA on interneurons either in O/A (vulnerable to KA) or in strata radiatum and lacunosum‐moleculare (R/LM) (resistant to KA) by using whole‐cell recording and calcium imaging. Results: GAD‐, PV‐ and SS‐positive cells in O/A were decreased after KA treatment in P20 and P30 rats. Both short (1‐min) and long (10‐min) applications of KA produced similar tetrodotoxin (TTX)‐insensitive membrane depolarization and decrease in input resistance in O/A and R/LM interneurons. KA responses were antagonized by CNQX and GYKI52466, suggesting AMPA receptor activation. KA also generated a similar increase in intracellular Ca2+ in O/A and R/LM interneurons, which was antagonized by CNQX and GYKI52466. Conclusions: The selective vulnerability of GAD‐, PV‐, and SS‐immunopositive O/A interneurons in the KA model may not arise from cell‐specific short‐term membrane effects or calcium responses induced by KA, but from other glutamate receptor‐mediated excitotoxic processes.
Periventricular White Matter Flumazenil Binding and Postoperative Outcome in Hippocampal Sclerosis
Authors: Hammers Alexander , Koepp Matthias J. , Brooks David J. , Duncan John S. 
Published: June 2005

Summary:  Purpose: In patients with hippocampal sclerosis (HS), anterior temporal lobe resection offers the possibility of a long‐lasting suppression of seizures in two thirds of patients. White matter (WM) [11C]flumazenil volume of distribution (FMZ‐Vd) reflects the number of neuronal cell bodies in WM. Our objective was to correlate WM FMZ‐Vd in patients with unilateral HS and postsurgical outcome. Methods: We performed [11C]FMZ‐PET in 15 patients with refractory mesial temporal lobe epilepsy (mTLE) and a quantitative MRI diagnosis of unilateral HS subsequently histologically verified in all cases. Median follow‐up was 7 years (range, 6–9 years). Metabolite‐corrected arterial plasma input functions and spectral analysis were used to generate parametric images of [11C]FMZ‐Vd. Statistical parametric mapping (SPM99) with explicit masking was used to investigate the entire brain volume including WM. Results: Eight patients had Engel class IA outcome (completely seizure free since surgery), and seven were not seizure free. Comparison of seizure‐free patients with those who continued to have seizures after surgery revealed areas of increased FMZ binding around the posterior horns of the ipsilateral (z = 3.7) and contralateral (z = 2.7) ventricles in those with suboptimal outcomes. Conclusions: Preoperative [11C]FMZ‐PET can detect periventricular increases of WM FMZ binding, implying heterotopic neurons in WM, in patients with mTLE. The presence of such increases correlates with a poorer outcome.