bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of interspecific interference competition in character displacement and the evolution of competitor recognition
Authors: Grether Gregory F. , Losin Neil , Anderson Christopher N. , Okamoto Kenichi 
Published: August 2009

AbstractThe extent to which interspecific interference competition has contributed to character evolution is one of the most neglected problems in evolutionary biology. When formerly allopatric species come into secondary contact, aggressive interactions between the species can cause selection on traits that affect interspecific encounter rates (e.g. habitat preferences, activity schedules), competitor recognition (e.g. colouration, song), and fighting ability (e.g. weaponry, body size). We define agonistic character displacement (ACD) as the process of phenotypic evolution in a population caused by interference competition with one or more sympatric species and which results in shifts in traits that affect the rate, intensity or outcome of interspecific aggression. After clarifying the relationships between ACD and other evolutionary processes that may occur when species come into secondary contact, we develop an individual‐based, quantitative genetic model to examine how traits involved in competitor recognition would be expected to evolve under different secondary contact scenarios. Our simulation results show that both divergence and convergence are possible outcomes, depending on the intensity of interspecific exploitative competition, the costs associated with mutualversusunilateral recognition, and the extent of phenotypic differences prior to secondary contact. We then devise a set of eight criteria for evaluating putative examples of ACD and review the empirical literature to assess the strength of existing evidence and to identify promising avenues for future research. Our literature search revealed 33 putative examples of ACD across insects, fishes, bats, birds, lizards, and amphibians (15 divergence examples; 18 convergence examples). Only one example satisfies all eight criteria for demonstrating ACD, but most case studies satisfy four or more criteria. The current state of the evidence for ACD is similar to the state of the evidence for ecological character displacement just 10 years ago. We conclude by offering suggestions for further theoretical and empirical research on ACD.
A proof‐of‐principle gel‐free proteomics strategy for the identification of predictive biomarkers for the onset of pre‐eclampsia
Authors: Blankley RT , Gaskell SJ , Whetton AD , Dive C , Baker PN , Myers JE 
Published: August 2009

Objective  Progress in the prevention and treatment of women at risk of pre‐eclampsia (PE) still remains hindered by the lack of clinical screening tools that can accurately predict which mothers are at risk. The identification and validation of predictive biomarkers is therefore seen as a critical milestone towards improved healthcare provision and the clinical testing of new therapeutic strategies. Gel‐free proteomic technologies offer the capability of analysing hundreds of plasma proteins simultaneously, but as yet these methods have not been applied to pregnancy complications. To assess the feasibility of such an approach to plasma biomarker research in pregnancy we have applied the technique to samples from women with PE to gestation‐matched controls.Sample  Pooled plasma samples taken at time of disease from women with PE (n = 23) and gestation‐matched controls (n = 23).Methods  Proteomics strategy for relative quantification of proteins using mass spectrometry.Results  We identified several differences, including elevated levels of endoglin, PAPP‐A and PSG1 in PE plasma. Increased levels of endoglin were validated using immunoassay analysis of individual plasma samples.Conclusions  Although at a relatively early stage, this mass spectrometry‐based approach shows promise as a tool to identify global protein changes in plasma. The application of these methods to pre‐disease samples is the next step in the identification of clinically useful biomarkers.
The more you introduce the more you get: the role of colonization pressure and propagule pressure in invasion ecology
Authors: Lockwood Julie L. , Cassey Phillip , Blackburn Tim M. 
Published: August 2009

AbstractAim We argue that ‘propagule pressure’, a key term in invasion biology, has been attributed at least three distinct definitions (with usage of a related term causing additional confusion). All of the definitions refer to fundamental concepts within the invasion process, with the result that the distinct importance of these different concepts has been at best diluted, and at worst lost.Location Global.Methods We reviewed pertinent literature on propagule pressure to resolve confusion about different uses of the term ‘propagule pressure’ and we introduced a new term for one variant, colonization pressure. We conducted a computer simulation whereby the introduction of species is represented as a simple sampling process to elucidate the relationship between propagule and colonization pressure.Results We defined colonization pressure as the number of species introduced or released to a single location, some of which will go on to establish a self‐sustaining population and some of which will not. We subsequently argued that colonization pressure should serve as a null hypothesis for understanding temporal or spatial differences in exotic species richness, as the more species that are introduced, the more we should expect to establish. Finally, using a simple simulation, we showed that propagule pressure is related to colonization pressure, but in a non‐linear manner.Main conclusion We suggest that the nature of the relationship between propagule pressure and colonization pressure, as well as the efficacy of various proxy measures of each, require more detailed exploration if invasion ecology is to continue to develop into a more predictive science.
The effectiveness of questionnaires in the determination of Contact Lens Induced Dry Eye
Authors: Michel M. , Sickenberger W. , Pult H. 
Published: August 2009

AbstractPurpose:  This study investigates how well the recently introduced Ocular Comfort Index (OCI) and the more established McMonnies Dry Eye Index are able to detect contact lens induced dry eye (CLIDE).Methods:  Seventy volunteer contact lens wearers (mean age = 28.7 ± 8.0; 52 female, 18 male) were grouped as CLIDE positive or CLIDE negative depending on three sets of criteria: Method I: objective (tear meniscus height, lid parallel conjunctival folds, phenol red thread test and tear break‐up time); Method II: objective and/or subjective [contact lens dry eye questionnaire (CLDEQ)] (i.e. being positive by Method I and/or Method III); Method III: subjective (CLDEQ). Symptoms were measured using the McMonnies Dry Eye Index and the OCI. Discrimination was analysed by the receiver operating characteristic (ROC) curves; positive predictive values (PPV) and cut‐off values were calculated.Results:  ROC results for Methods I and II were statistically significant only for the McMonnies (p = 0.008; p < 0.001; respectively). In Method III ROC results were statistically significant for both the McMonnies (p = 0.001) and OCI (p = 0.005). The McMonnies showed the best prediction of Method I [0.646/10.5 (PPV/cut‐off value)], while the OCI gave the best predictability in Method III only (0.518/30.6).Conclusion:  A McMonnies scoring of ≥10.5 or an OCI scoring of ≥30.6 indicates CLIDE. The McMonnies performs better in prediction of CLIDE than the OCI.
Glial cell factors and the outer blood retinal barrier
Authors: Constable Paul A. , Lawrenson John G. 
Published: August 2009

AbstractThe retinal pigment epithelium is an important barrier to drug transport as well as contributing to the normal functioning of the photoreceptors. The contributions of glial cells in the retina to the maintenance and development of this barrier is important. There is evidence that retinal secreted factors play a role in the induction and maintenance of the outer blood retinal barrier. One possible source of such factors are the retinal glial cells, astrocytes and Müller cells, which may influence tight junction formation and maturation. The aim of this study was to examine the changes in the trans‐epithelial resistance (TER), as a measure of barrier integrity, on cell lines of epithelial origin (ECV304 and ARPE‐19) following co‐culture with glial cell lines (C6 and MIO‐M1) or with the addition of medium conditioned by these cells. One cell line, ECV304, showed a significant increase in the TER in response to glial secreted factors whilst ARPE‐19 did not. This finding suggests that ECV304 responds well to glial factors and may be useful for further studies of the factors that affect tight junction formation through glial cell induction in vitro.
A versatile optoelectronic aid for low vision patients
Authors: Peláez‐Coca María Dolores , Vargas‐Martín Fernando , Mota Sonia , Díaz Javier , Ros‐Vidal Eduardo 
Published: August 2009

AbstractThe purpose of this work is to describe a versatile optoelectronic aid for low vision rehabilitation based on reconfigurable hardware. This aid is easily adaptable to diverse pathologies (with different associated processing tasks) and to the progression of the visual impairment. This platform has a mobile configuration that uses a see‐through head‐mounted display (Nomad). We have implemented different types of vision enhancement on this versatile platform, and briefly summarize here their computational costs (in terms of hardware resource requirements). We have evaluated two representative capabilities of this aid (Augmented View and digital zoom) with measurements of visual acuity, contrast sensitivity and visual field. We have tested the Nomad head‐mounted display and the Augmented View modality, in eight subjects with retinitis pigmentosa: the digital zoom was tested in six low vision subjects and nine normally‐sighted subjects. We show that the Nomad display with Augmented View configuration does not impair the residual vision; and that there is an increase in visual acuity (VA) with the digital zoom configuration. The major advantage of this platform is that it can easily embed different image processing tasks and since it is based on a FPGA device, it can be specifically configured to tasks requiring real‐time processing.
The importance of grating orientation in contrast sensitivity following refractive surgery
Authors: Tahir Humza J. , Parry Neil R. A. , Brahma Arun , Ikram Khalid , Murray Ian J 
Published: August 2009

AbstractHigher‐order aberrations degrade visual performance when the pupil is large, particularly in eyes that have abnormally high amounts of aberrations, such as those that have undergone refractive surgery. Geometrical optics predicts that asymmetrical aberrations such as coma can produce orientation selective effects, much like uncorrected astigmatism. Coma is also one of the main aberrations to increase following refractive surgery. Orientation may therefore be an important parameter when testing grating based contrast sensitivity, particularly in refractive surgery patients. Contrast sensitivity to four orientations of a 12 cycles deg−1 sine wave grating was measured in normals (n = 34) and refractive surgery patients (n = 12). In over a third of normal subjects the higher‐order aberrations produced a significant orientation‐specific change in contrast sensitivity (13 out of 34 eyes, p < 0.05). No significant differences existed in the aberrations between those that displayed orientation‐selective changes and those that did not. In subjects who underwent refractive surgery those that displayed orientation selective changes had significantly higher amounts of overall aberrations and also higher amounts of primary coma than those that did not. These results indicate that grating orientation is an important factor when assessing the effects of higher‐order aberrations on contrast sensitivity.
Role of glaciohydraulic supercooling in the formation of stratified facies basal ice: Svínafellsjökull and Skaftafellsjökull, southeast Iceland
Authors: COOK SIMON J. , ROBINSON ZOE P. , FAIRCHILD IAN J. , KNIGHT PETER G. , WALLER RICHARD I. , BOOMER IAN 
Published: August 2009

Cook, S. J., Robinson, Z. P., Fairchild, I. J., Knight, P. G., Waller, R. I. & Boomer, I. 2009: Role of glaciohydraulic supercooling in the formation of stratified facies basal ice: Svínafellsjökull and Skaftafellsjökull, southeast Iceland. Boreas, 10.1111/j.1502‐3885.2009.00112.x. ISSN 0300‐9483.There is need for a quantitative assessment of the importance of glaciohydraulic supercooling for basal ice formation and glacial sediment transfer. We assess the contribution of supercooling to stratified facies basal ice formation at Svínafellsjökull and Skaftafellsjökull, southeast Iceland, both of which experience supercooling. Five stratified basal ice subfacies have previously been identified at Svínafellsjökull, but their precise origins have not been determined. Analysis of stratified basal ice stable isotope compositions (δ18O and δD), spatial distribution and physical characteristics demonstrates that two subfacies present at both glaciers are consistent with supercooling. These ‘supercool’ subfacies account for 42% of stratified facies exposed at Svínafellsjökull, although estimates at Skaftafellsjökull are precluded by limited basal ice exposure. Owing to their high debris contents, supercooling‐related facies contribute a debris flux of 4.8 to 9.6 m3 m−1 a−1 at Svínafellsjökull (83% of the stratified facies debris flux). Other stratified subfacies, formed by non‐supercooling processes, account for 58% of the stratified basal ice at Svínafellsjökull, but only contribute a debris flux of 1.0 to 2.0 m3 m−1 a−1 (17% of the stratified facies debris flux). We conclude that supercooling has a significant role in glacial sediment transfer, although in stratified basal ice formation its role is less significant at these locations than has been reported elsewhere.
Development and Pilot Testing of Computerized Order Entry Algorithms for Geriatric Problems in Nursing Homes
Authors: Colón‐Emeric Cathleen S. , Schmader Kenneth E. , Twersky Jack , Kuchibhatla Maragantha , Kellum Sally , Weinberger Morris 
Published: August 2009

OBJECTIVES: To develop order entry algorithms for five common nursing home problems and to test their acceptance, use, and preliminary effect on nine quality indicators and resource utilization.DESIGN: Pre–post, quasi‐experimental study.SETTING: Two Department of Veterans Affairs nursing homes.PARTICIPANTS: Randomly selected residents (N=265) with one or more target conditions and 42 nursing home providers.INTERVENTION: Expert panels developed computerized order entry algorithms based on clinical practice guidelines. Each was displayed on a single screen and included an array of diagnostic and treatment options and means to communicate with the interdisciplinary team.MEASUREMENTS: Medical records were abstracted for the 6 months before and after deployment for quality indicators and resource utilization.RESULTS: Despite positive provider attitudes toward the computerized order entry algorithms, their use was infrequent and varied according to condition: falls (73.0%), fever (9.0%), pneumonia (8.0%), urinary tract infection (7.0%), and osteoporosis (3.0%). In subjects with falls, trends for improvements in quality measures were observed for six of the nine measures: measuring orthostatic blood pressure (17.5–30.0%, P=.29), reducing neuroleptics (53.8–75.0%, P=.27), reducing sedative‐hypnotics (16.7–50.0%, P=.50), prescription of calcium (22.5–32.5%, P=.45), vitamin D (20.0–35.0%, P=.21), and external hip protectors (25.0–47.5%, P=.06). Little improvement was observed in the other conditions (documentation of vital signs, physical therapy referrals, or reduction of benzodiazepines or antidepressants). There was no change in resource utilization.CONCLUSION: Computerized order entry algorithms were used infrequently, except for falls. Further study may determine whether their use leads to improved care.
Pain, Functional Limitations, and Aging
Authors: Covinsky Kenneth E. , Lindquist Karla , Dunlop Dorothy D. , Yelin Edward 
Published: August 2009

OBJECTIVES: To examine the relationship between functional limitations and pain across a spectrum of age, ranging from mid life to advanced old age.DESIGN: Cross‐sectional study.SETTING: The 2004 Health and Retirement Study (HRS), a nationally representative study of community‐living persons aged 50 and older.PARTICIPANTS: Eighteen thousand five hundred thirty‐one participants in the 2004 HRS.MEASUREMENTS: Participants who reported that they were often troubled by pain that was moderate or severe most of the time were defined as having significant pain. For each of four functional domains, subjects were classified according to their degree of functional limitation: mobility (able to jog 1 mile, able to walk several blocks, able to walk one block, unable to walk one block), stair climbing (able to climb several flights, able to climb one flight, not able to climb a flight), upper extremity tasks (able to do 3, 2, 1, or 0), and activity of daily living (ADL) function (able to do without difficulty, had difficulty but able to do without help, need help).RESULTS: Twenty‐four percent of participants had significant pain. Across all four domains, participants with pain had much higher rates of functional limitations than subjects without pain. Participants with pain were similar in terms of their degree of functional limitation to participants 2 to 3 decades older. For example, for mobility, of subjects aged 50 to 59 without pain, 37% were able to jog 1 mile, 91% were able to walk several blocks, and 96% were able to walk one block without difficulty. In contrast, of subjects aged 50 to 59 with pain, 9% were able to jog 1 mile, 50% were able to walk several blocks, and 69% were able to walk one block without difficulty. Subjects aged 50 to 59 with pain were similar in terms of mobility limitations to subjects aged 80 to 89 without pain, of whom 4% were able to jog 1 mile, 55% were able to walk several blocks, and 72% were able to walk one block without difficulty. After adjustment for demographic characteristics, socioeconomic status, comorbid conditions, depression, obesity, and health habits, across all four measures, participants with significant pain were at much higher risk for having functional limitations (adjusted odds ratio (AOR)=2.85, 95% confidence interval (CI)=2.20–3.69, for mobility; AOR=2.84, 95% CI=2.48–3.26, for stair climbing; AOR=3.96, 95% CI=3.43–4.58, for upper extremity tasks; and AOR=4.33; 95% CI=3.71–5.06, for ADL function).CONCLUSION: Subjects with pain develop the functional limitations classically associated with aging at much earlier ages.
Comparison of the Marginal Fit of Pressable Ceramic to Metal Ceramic Restorations
Authors: Holden Jason E. , Goldstein Gary R. , Hittelman Eugene L. , Clark Elizabeth A. 
Published: August 2009

Abstract Purpose: The aim of this in vitro study was to compare the marginal adaptation of a pressed ceramic material, when used with and without a metal substructure, to a traditional feldspathic porcelain‐fused‐to‐metal restoration with a porcelain butt margin. Materials and Methods: A maxillary central incisor typodont tooth was prepared with a 1.5 mm 360° shoulder with rounded internal line angle, and 30 polyether impressions were made. Dies were poured in type IV dental stone, and 30 restorations were fabricated: 10 metal ceramic restorations (MCR) with porcelain butt joints, 10 pressed to metal restorations (PTM), and 10 all‐ceramic restorations (PCR). All restorations were evaluated on their respective dies at 45× magnification using an Olympus SZX‐12, measurements of the marginal openings were made, and ANOVA and Scheffé post hoc tests were used to evaluate the data. Results: The mean marginal opening was 72.2 ± 5.9 μm for MCR, 49.0 ± 5.9 μm for PTM, and 55.8 ± 5.9 μm for PCR. The post hoc tests showed that there was a statistical difference between the marginal adaptation of the PTM and MCR groups (p < 0.05). There was no significant difference in marginal adaptation between the PTM and the PCR groups, or the PCR and the MCR groups. Conclusions: The PTM group demonstrated a smaller mean marginal opening than the MCR group. The mean marginal openings of all three groups were within a clinically acceptable range.
A novel rapid and effective donor arm disinfection method
Authors: McDonald Carl , McGuane Siobhan , Thomas Julia , Hartley Stephen , Robbins Steve , Roy Anjana , Verlander Neville , Barbara John 
Published: August 2009

BACKGROUND: The aim of the study was to derive a donor arm disinfection technique that was rapid, but with a disinfection efficacy equivalent to a previous “best‐practice” technique. This method consisted of a two‐stage procedure with an initial application of 70% isopropyl alcohol and then 2% tincture of iodine (IATI). The total time for the IATI method was 2 minutes in duration. A rapid technique (1 min in duration) was needed to obviate potential problems due to increased donor waiting time, had the IATI method been implemented at blood donation sessions.STUDY DESIGN AND METHODS: A direct swabbing and plating technique was used to enumerate bacteria present before and after disinfection. In total, seven methods were evaluated.RESULTS: The chlorhexidine/alcohol applicator (CAA) disinfection device containing 1.5 mL of 2% chlorhexidine gluconate and 70% isopropyl alcohol (99.91% reduction; confidence limits, 99.55%, 99.98%) was shown to have equivalent disinfection efficacy as the IATI method (99.89% reduction; confidence limits, 99.36%, 99.98%; p = 0.86). Procedural time for the 1.5‐mL CAA method was 1 minute thereby avoiding potential problems of increased donor waiting time, inherent in the IATI 2‐minute procedure at blood donation sessions.CONCLUSIONS: The 1.5‐mL CAA disinfection method offers blood services a rapid and effective donor arm disinfection procedure. In 2006, the 1.5‐mL CAA procedure was implemented throughout the entire English blood service for all donations.
In vitro reaction of human osteoblasts on alumina‐toughened zirconia
Authors: Kohal Ralf J. , Baechle Maria , Han Jung S. , Hueren Dennis , Huebner Ute , Butz Frank 
Published: August 2009

AbstractObjectives: Alumina toughening enhances the mechanical properties of zirconia ceramics but the biocompatibility of this material has rarely been addressed. In this study, we examined the osteoblast response to alumina‐toughened zirconia (ATZ) with different surface topographies.Material and methods: Human osteoblasts isolated from maxillary biopsies of four patients were cultured and seeded onto disks of the following substrates: ATZ with a machined surface, airborne‐particle abraded ATZ, airborne‐particle abraded and acid etched ATZ. Airborne‐particle abraded and acid etched titanium (SLA) and polystyrene disks served as a reference control. The surface topography of the various substrates was characterized by profilometry (Ra, Rp−v) and scanning electron microscopy (SEM). Cell proliferation, cell‐covered surface area, alkaline phophatase (ALP) and osteocalcin production were determined. The cell morphology was analyzed on SEM images.Results: The surface roughness of ATZ was increased by airborne‐particle abrasion, but with the Ra and Rp−v values showing significantly lower values compared with SLA titanium (Mann‐Whitney U‐test P<0.05). The proliferation assay revealed no statistically significant differences between the ATZ substrates, SLA titanium and polystyrene (Kruskal–Wallis test, P>0.05). All substrates were densely covered by osteoblasts. ALP and osteocalcin production was similar on the examined surfaces. Cell morphology analysis revealed flat‐spread osteoblasts with cellular extensions on all substrates.Conclusions: These results indicate that ATZ may be a viable substrate for the growth and differentiation of human osteoblasts. Surface modification of ATZ by airborne‐particle abrasion alone or in combination with acid etching seems not to interfere with the growth and differentiation of the osteoblasts.