bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blepharokymographic Analysis of Eyelid Motion in Bell's Palsy
Authors: Choi Seung‐Ho , Yoon Tae Hyun , Lee Kwang‐Sun , Ahn Joong Ho , Chung Jong Woo 
Published: February 2007

AbstractObjective: To present characteristics of eyelid motion measured by blepharokymography in Bell's palsy patients and to discuss possible roles and limitations of blepharokymography.Study Design. Retrospective analysis.Methods: The study included 72 patients with Bell's palsy who presented to the Department of Otolaryngology at Asan Medical Center, Seoul, Korea, between April 2002 and March 2005, and who underwent both electroneuronography and blepharokymography. Parameters of eyelid motion were measured using revised blepharokymography. Correlations between blepharokymography and electroneuronography or House‐Brackmann grade were examined by Spearman rank correlation and Kendall's τ‐b correlation, respectively.Results: Compared with the normal side, all parameters of eyelid motion except opening time were decreased on the palsy side, with peak closing velocity showing the greatest difference (40.2%). On average, paralytic eyelids moved down 6.5 mm in 277 ms with a peak velocity of 55.4 mm/s, whereas normal eyelids moved down 9.7 mm in 214 ms, with a peak velocity of 142.6 mm/s. Subtle paralytic eyelid motion or “lid lag” could be objectively documented by blepharokymography to have longer and gentler downward slopes in displacement curves. Most blepharokymographic parameters correlated with ocular electroneuronography and House‐Brackmann grade.Conclusions: Slow or incomplete closure of paralytic eyelids can be graphically and numerically analyzed by blepharokymography. Blepharokymography may be useful for evaluating status, predicting prognosis, and assessing effects of rehabilitative procedures, including gold weight implants in patients with facial palsy.
Gene expression profiling in a mouse model of Helicobacter‐induced gastric cancer
Authors: Takaishi Shigeo , Wang Timothy C. 
Published: February 2007

We have previously reported that a synergistic interaction between hypergastrinemia and Helicobacter felis (H. felis) infection accelerates gastric carcinogenesis in mice, but the precise mechanism for this interaction has not been clarified. Consequently, we undertook an oligonucleotide cDNA microarray study to investigate changes in gene expression in this model system. Male hypergastrinemic transgenic (INS‐GAS) mice with 6‐months H. felis infection were compared with three different age, strain and gender‐matched control groups: (i) INS‐GAS mice without H. felis infection; (ii) non‐transgenic FVB/N mice with H. felis infection; and (iii) non‐transgenic FVB/N mice without H. felis infection. Complementary RNA derived from whole stomach were hybridized to the Affymetrix GeneChip murine U74Av2 array. Among 12 000 cDNA spotted on each chip, 35 cDNA were upregulated and 41 cDNA were downregulated more than twofold in H. felis‐infected INS‐GAS mice compared with all three control groups. Expression changes were validated in 12 selected genes by northern hybridization and/or quantitative real‐time reverse transcription polymerase chain reaction (RT‐PCR). Confirmed upregulated genes included Reg I, amphiregulin, MMP‐10, MMP‐13, claudin‐7 and chitinase 3‐like 1, while confirmed downregulated genes included H/K‐ATPase alpha and beta subunits, intrinsic factor, somatostatin, galectin‐2 and apolipoprotein A‐I. Immunohistochemical analysis of MMP‐10, amphiregulin, H/K‐ATPase beta subunit and galectin‐2 confirmed these expression changes at the protein level, and MMP‐10 was mainly detected in stromal cells of submucosal region, while the other three genes were expressed in gastric epithelial cells. Taken together, gene expression profiling of this mouse model may provide novel insights into Helicobacter‐induced gastric carcinogenesis. (Cancer Sci 2007; 98: 284–293)
Courtship displays in anurans and lizards: theoretical and empirical contributions to our understanding of costs and selection on males due to female choice
Authors: SULLIVAN BRIAN K. , KWIATKOWSKI MATTHEW A. 
Published: February 2007

Summary

Male frogs and toads expend considerable energy and experience potential predation risk while calling in breeding aggregations; similarly, male lizards display behaviourally and exhibit striking colour patterns during courtship interactions. These apparently costly displays of male anuran amphibians and squamate reptiles have been argued to play an important role in mate selection by females. Although female preferences for male display traits under controlled conditions have been documented for both taxonomic groups, directional selection on male displays has rarely been adequately assessed under natural conditions.
We discuss theoretical and empirical considerations of display costs in the context of sexual selection due to female preferences in anurans and lizards. We review experimental evidence of female preferences for apparently costly displays by males and estimation of selection on male traits due to female choice in the field in these taxonomic groups.
Evidence of female preferences for apparently costly display traits is not uncommon for thoroughly studied populations, and there is some field evidence of significant selection on these traits in at least one well studied group: prolonged breeding toads. Studies have been hampered by confusion over the definitions of costs, difficulty in adequately describing variation in male displays, and overly simplistic approaches to documentation of female preferences.
Future work should include recognition of variation in definitions of cost in relation to male display behaviour, acknowledgement that female choice may be based on multiple male characteristics, and that considerable effort, including documentation of consistency in male behaviour, is required before inferences regarding the importance of female choice in sexual selection can be drawn.
Risk factors for developing apical periodontitis in a general population
Authors: Kirkevang L.‐L. , Væth M. , Hörsted‐Bindslev P. , Bahrami G. , Wenzel A. 
Published: February 2007

AbstractAim  To identify and describe individual and tooth‐specific factors associated with the incidence or the persistence of apical periodontitis (AP) in a general population.Methodology  In 1997, 616 randomly selected individuals had a full‐mouth radiographic survey. In 2003, 77% of the participants returned for a new full‐mouth radiographic examination. All teeth were assessed individually and data recorded for caries, marginal bone level, and tooth restorations. Multiple logistic regression analyses were performed to identify predictors of AP in the individual. Conditional logistic regression analyses were used to identify risk factors for development of AP in a tooth. Independent variables included a number of individual and tooth‐specific variables.Results  Root fillings, coronal restorations, primary carious lesions, and reduced marginal bone level were associated with the incidence of AP in the individual. In teeth, the quality and presence of a coronal restoration was associated with the incidence of AP, and presence of a root filling also increased the risk of developing AP. Furthermore, an increased risk of developing AP was seen in relation to primary carious lesions, reduced marginal bone level, and molar teeth. The quality of the root filling was not associated with the incidence of AP, but the results suggest an association between the quality of the root filling and the healing of AP.Conclusions  Results from the present study demonstrate that it is important to provide high quality dental restorations to minimize the risk of pulpal infection. The clinical focus, in relation to the incidence of AP, should be on improving the quality of the coronal restoration. The quality of a root filling was not associated with the incidence of AP, but may be of importance in relation to healing of AP.
Evaluation of a reflective learning intervention to improve critical thinking in novice nurses
Authors: Forneris Susan Gross , Peden‐McAlpine Cynthia 
Published: February 2007

Abstract Title. Evaluation of a reflective learning intervention to improve critical thinking in novice nurses Aim.  This paper reports a study to determine if a reflective contextual learning intervention would improve novice nurses’ critical thinking skills during the first 6 months of their practice.Background.  Nursing research evaluating the development of critical thinking in novice nursing practice is limited. The continual struggle by nurse educators to improve critical thinking demonstrates the need for innovative educational interventions that assist in the development of critical thinking as novice nurses enter into practice.Method.  This small case study was conducted in the United States of America in 2004 with six student/preceptor dyads. The contextual learning intervention was the case through which the novice nurses’ critical thinking were analysed using Stake's phases of data analysis. Specific questions (i.e. novice nurses’ use of reflection, context, dialogue, time) guided the analysis. Repeating patterns were coded and isolated and later collapsed/enhanced as the analysis moved forward.Findings.  Three main themes describe the novice nurses’ development of critical thinking: (1) influence of anxiety and power on critical thinking; putting pieces together; (2) questioning as critical thinking: sequential thinking to contextual thinking; and (3) emergence of the intentional critical thinker.Conclusion.  Used as a reflective practicum, contextual learning can be a model of clinical learning in nursing education that develops the contextual, reflective nature of critical thinking.
Does location matter? A study of the public’s preferences for surgical care provision
Authors: Schwappach David L. B. , Strasmann Thomas J. 
Published: February 2007

AbstractObjectives  As in other countries, office‐based surgeons, outpatient clinics and hospitals in Germany are in increasing competition to each other. However, little is known about potential patients’ preferences for surgical care provision. The aim of this study was to investigate the general publics’ preferences towards location and other attributes of surgical treatment.Methods  An economic evaluation technique, discrete choice analysis, was administered in a survey to a sample of a German general public Internet panel, representative in terms of age, gender and education. Responders were asked to choose their preferred provider of surgical care in a series of pairwise choices, defined by five attributes. Regression analysis was used to quantify preferences towards characteristics of care and to calculate utilities of treatment scenarios. The strength of preferences and the rate at which participants were willing to trade among attributes were estimated.Results  The response rate was 76% (n = 1134). ‘Specialization and experience of provider’ was the single most important attribute, followed by ‘waiting times’ and ‘staff continuity’. Subjects traded a 4‐week waiting time to obtain surgery at a highly specialized institution. Responders favoured outpatient clinics over office‐based and inpatient surgery, but ‘location of care’ preferences were only weak. Whether participants had undergone surgery in the past had only minor effect on their preferences.Conclusions  Potential patients base their choice between providers mainly on characteristics of care delivery and not location of care. The competition between and among providers of surgical care of different types of institutional organization will be determined by what is offered to patients.
A new measurement technique reveals rapid post‐illumination changes in the carbon isotope composition of leaf‐respired CO2
Authors: BARBOUR MARGARET M. , MCDOWELL NATE G. , TCHERKEZ GUILLAUME , BICKFORD CHRISTOPHER P. , HANSON DAVID T. 
Published: February 2007

ABSTRACTWe describ an open leaf gas exchange system coupled to a tunable diode laser (TDL) spectroscopy system enabling measurement of the leaf respiratory CO2 flux and its associated carbon isotope composition (δ13CRl) every 3 min. The precision of δ13CRl measurement is comparable to that of traditional mass spectrometry techniques. δ13CRl from castor bean (Ricinus communis L.) leaves tended to be positively related to the ratio of CO2 produced to O2 consumed [respiratory quotient (RQ)] after 24–48 h of prolonged darkness, in support of existing models. Further, the apparent fractionation between respiratory substrates and respired CO2 within 1–8 h after the start of the dark period was similar to previous observations. In subsequent experiments, R. communis plants were grown under variable water availability to provide a range in δ13C of recently fixed carbohydrate. In leaves exposed to high light levels prior to the start of the dark period, CO2 respired by leaves was up to 11‰ more enriched than phloem sap sugars within the first 10–15 min after plants had been moved from the light into the dark. The 13C enrichment in respired CO2 then decreased rapidly to within 3–7‰ of phloem sap after 30–60 min in the dark. This strong enrichment was not observed if light levels were low prior to the start of the dark period. Measurements of RQ confirmed that carbohydrates were the likely respiratory substrate for plants (RQ > 0.8) within the first 60 min after illumination. The strong 13C enrichment that followed a high light‐to‐dark transition coincided with high respiration rates, suggesting that so‐called light‐enhanced dark respiration (LEDR) is fed by 13C‐enriched metabolites.
Effects of hydraulic architecture and spatial variation in light on mean stomatal conductance of tree branches and crowns
Authors: EWERS B. E. , OREN R. , KIM H.‐S. , BOHRER G. , LAI C.‐T. 
Published: February 2007

ABSTRACTIn aPinus taedaL. (loblolly pine) plantation, we investigated whether the response to vapour pressure deficit (D) of canopy average stomatal conductance (GS) calculated from sap flux measured in upper and lower branches and main stems follows a hydraulically modelled response based on homeostasis of minimum leaf water potential (ΨL). We tested our approach over a twofold range of leaf area index (L; 2–4 m2 m−2) created by irrigation, fertilization, and a combination of irrigation and fertilization relative to untreated control. We found thatGSscaled well from leaf‐level porometery [porometry‐based stomatal conductance (gs)] to branch‐estimated and main stem‐estimatedGS. The scaling from branch‐ to main stem‐estimatedGSrequired using a 45 min moving average window to extract the diurnal signal from the large high‐frequency variation, and utilized a light attenuation model to weigh the contribution of upper and lower branch‐estimatedGS. Our analysis further indicated that, regardless ofL, lower branch‐estimatedGSrepresented most of the main stem‐estimatedGSin this stand. We quantified the variability in both upper and lower branch‐estimatedGSby calculating the SD of the residuals from a moving average smoothed diurnal. A light model, which incorporated penumbral effects on vertical distribution of direct light, was employed to estimate the variability in light intensity at each canopy level in order to explain the increasing SD of both upper and lower branch‐estimatedGSwith light. The results from the light model showed that the upper limit of the variability in individual branch‐estimatedGScould be attributed to incoming light, but not the variation below that upper limit. A porous medium model of water flow in trees produced a pattern of variation below the upper limit that was consistent with the observed variability in branch‐estimatedGS. Our results indicated that stems acted to buffer leaf‐ and branch‐level variation and might transmit a less‐variable water potential signal to the roots.
Structural and functional characterization of ferredoxin‐NADP+‐oxidoreductase using knock‐out mutants of Arabidopsis
Authors: Lintala Minna , Allahverdiyeva Yagut , Kidron Heidi , Piippo Mirva , Battchikova Natalia , Suorsa Marjaana , Rintamäki Eevi , Salminen Tiina A. , Aro Eva‐Mari , Mulo Paula 
Published: February 2007

SummaryIn Arabidopsis thaliana, the chloroplast‐targeted enzyme ferredoxin‐NADP+‐oxidoreductase (FNR) exists as two isoforms, AtLFNR1 and AtLFNR2, encoded by the genes At5g66190 and At1g20020, respectively. Both isoforms are evenly distributed between the thylakoids and soluble stroma, and they are separated by two‐dimensional electrophoresis in four distinct spots, suggesting post‐translational modification of both isoforms. To reveal the functional specificity of AtLFNR1, we have characterized the T‐DNA insertion mutants with an interrupted At5g66190 gene. Absence of AtLFNR1 resulted in a reduced size of the rosette with pale green leaves, which was accompanied by a low content of chlorophyll and light‐harvesting complex proteins. Also the photosystem I/photosystem II (PSI/PSII) ratio was significantly lower in the mutant, but the PSII activity, measured as the FV/FM ratio, remained nearly unchanged and the excitation pressure of PSII was lower in the mutants than in the wild type. A slow re‐reduction rate of P700 measured in the mutant plants suggested that AtLFNR1 is involved in PSI‐dependent cyclic electron flow. Impaired function of FNR also resulted in decreased capacity for carbon fixation, whereas nitrogen metabolism was upregulated. In the absence of AtLFNR1, we found AtLFNR2 exclusively in the stroma, suggesting that AtLFNR1 is required for membrane attachment of FNR. Structural modeling supports the formation of a AtLFNR1–AtLFNR2 heterodimer that would mediate the membrane attachment of AtLFNR2. Dimer formation, in turn, might regulate the distribution of electrons between the cyclic and linear electron transfer pathways according to environmental cues.
Opposite diel patterns of nitrogen fixation associated with salt marsh plant species (Spartina foliosaandSalicornia virginica) in southern California
Authors: Moseman Serena M. 
Published: February 2007

AbstractIn marine wetlands, nitrogen fixation is a potentially important nutrient source for nitrogen‐limited primary producers, but interactions between nitrogen fixers and different vascular plant species are not fully understood. Nitrogen fixation activity was compared in sediments vegetated by three plant species,Spartina foliosa,Salicornia virginica, andSalicornia bigeloviiin the Kendall Frost Reserve salt marsh in Mission Bay (CA). This study addressed the effects of plant type, day and night conditions, and sediment depths on nitrogen fixation. Higher rates of nitrogen fixation were associated withS. foliosathan with either of the twoSalicorniaspp., which are known to compete more effectively thanSpartinafor exogenous nitrogen in the salt marsh environment. Rates of nitrogen fixation, determined by acetylene reduction, in sediments vegetated byS. virginicawere low during the day (7.7 ± 1.2 μmol C2H4 m−2 h−1) but averaged 13 ± 6.6 μmol C2H4 m−2 h−1at night, with particularly high rates in samples from locations with visible cyanobacterial mats. The opposite diel pattern was found for sediments containingS. foliosaplants, in which average daytime and nighttime rates of nitrogen fixation were 62 ± 23 and 21 ± 15 μmol C2H4 m−2 h−1, respectively. ForS. foliosa, nitrogenase activity of rinsed roots and different sediment sections (0–1, or 4–5 cm depths) were measured. Although nitrogen fixation rates in vegetated sediment samples were substantial, all but one of rinsedS. foliosaroot samples (n = 12) and subsurface sediments at 4–5 cm depths failed to show nitrogen fixation activity after 2 h, suggesting that the most active nitrogen fixers in these systems likely reside in surface sediments. Further, nitrogenase activity in shaded and unshadedS. foliosasamples did not differ, suggesting that nitrogen fixers may not rapidly respond to changes in plant photosynthetic activity. Average nitrogen fixation rates inS. foliosa‐vegetated samples from the Mission Bay salt marsh were on the same order as those of highly productive Atlantic coast marshes, and this microbially‐mediated nitrogen source may be similarly substantial in other Mediterranean wetlands. Sediment abiotic variables seem to exert greater control upon nitrogen fixation activity than the effects of particular plant species. Nonetheless, dominant plant species may differ substantially in their reliance on nitrogen fixation as a nutrient source, with potentially important consequences for wetland conservation and restoration.
A genetic diversity analysis of wild Lespedeza populations based on morphological characters, allozyme and RAPD methods
Authors: Zhang J. Y. , Yuan Q. H. , Meng Y. Q. , Li X. L. , Nan Z. B. , Wang Y. R. , Zhang W. S. 
Published: February 2007

AbstractGenetic variability within and among 14 Chinese natural populations of Lespedeza Michx. Used mainly for wildlife food and cover and for erosion control was evaluated on the basis of morphological characteristics, allozyme markers and random amplified polymorphic DNAs (RAPDs). All methods disclosed a high degree of allelic heterogeneity among samples, also revealing a high degree of gene diversity. Genetic variation among populations was higher for RAPD than for enzyme loci. Correlation between morphological, allozyme and RAPD distance matrices were calculated by Mantel’ tests. There was a little disparity between the three level's distances on population relationships. However, there is a weak significant correlation (P < 0.001) between morphology and allozyme distances as well as morphology and RAPD distances, and the test of this correlation is very high.
Resolving Risk? Marriage and Creative Conjugality
Authors: Jackson Cecile 
Published: February 2007

ABSTRACTThe idea of rural women as risk‐averse food producers has been powerful and persistent and constitutes one of our most enduring generalizations. This contribution begins with some critical thoughts about the prevalent consensus on women and risk behaviour and goes on to discuss some counter examples of risk‐taking women farmers in Zimbabwe and Zambia. It argues that risk behaviours of these kinds are strongly related to the character of marriage and forms of conjugality, and considers more broadly how insurance and dependence are gendered. There is a danger of overdrawing, and exclusively emphasizing, household and marriage as sites of gender subordination and thereby losing sight of the value to women of domestic groups and the existence of class‐based solidarities and emotional investments, across gender, which are intertwined with gender subordinations. To recognize these (and other) positive aspects of institutions of kinship and marriage, without simultaneously endorsing subordination, requires a focus on change and women's agency within such institutions, and the happy thought that there is no such thing as the status quo. This study therefore considers myths made within different but overlapping contexts; first the idea of women as reliably risk averse (as well as disadvantaged in access to insurance) which holds sway in international development organizations and some gender analysis; and second, the myth of households as composed of entirely separate individuals with opposed gender interests, in which marriage is predominantly a contract legitimating the exploitation of women. Marriage works as a safety net for women in many contexts, as a form of insurance, but it may become an impediment to accumulation — a feature shared with other social security institutions.