bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissemination biases in ecology: effect sizes matter more than quality
Authors: Barto E. Kathryn , Rillig Matthias C.
Published: August 2011

Publication and citation decisions in ecology are likely influenced by many factors, potentially including journal impact factors, direction and magnitude of reported effects, and year of publication. Dissemination bias exists when publication or citation of a study depends on any of these factors. We defined several dissemination biases and determined their prevalence across many sub‐disciplines in ecology, then determined whether or not data quality also affected these biases. We identified dissemination biases in ecology by conducting a meta‐analysis of citation trends for 3867 studies included in 52 meta‐analyses. We correlated effect size, year of publication, impact factor and citation rate within each meta‐analysis. In addition, we explored how data quality as defined in meta‐analyses (sample size or variance) influenced each form of bias. We also explored how the direction of the predicted or observed effect, and the research field, influenced any biases. Year of publication did not influence citation rates. The first papers published in an area reported the strongest effects, and high impact factor journals published the most extreme effects. Effect size was more important than data quality for many publication and citation trends. Dissemination biases appear common in ecology, and although their magnitude was generally small many were associated with theory tenacity, evidenced as tendencies to cite papers that most strongly support our ideas. The consequences of this behavior are amplified by the fact that papers reporting strong effects were often of lower data quality than papers reporting much weaker effects. Furthermore, high impact factor journals published the strongest effects, generally in the absence of any correlation with data quality. Increasing awareness of the prevalence of theory tenacity, confirmation bias, and the inattention to data quality among ecologists is a first step towards reducing the impact of these biases on research in our field.
Separating the effect of mechanisms shaping species‐abundance distributions at multiple scales in a subtropical forest
Authors: Cheng Jiajia , Mi Xiangcheng , Nadrowski Karin , Ren Haibao , Zhang Jintun , Ma Keping
Published: August 2011

Species abundance distributions (SADs) play an important role in the current dispute over mechanisms shaping community assembly. Niche theory assumes differential occurrence of species in different habitats while neutral theory emphasizes stochastic events and dispersal. The previous tests of niche and neutral models shaping SADs lead to the claim that SADs are not informative for inferring underlying processes. Using spatial statistical models in a fully mapped 24‐ha subtropical forest in China, we first demonstrate that one can not distinguish between the effect of habitat heterogeneity and dispersal limitation on SADs by inspecting whether the observed SADs fall within 95% confidence intervals of the simulated SADs. Subsequently, we demonstrate that SADs can be used to detect mechanisms shaping SADS by comparing alternative process‐based models using model selection techniques. We found that dispersal limitation explain SADs at smaller spatial scales, while the combination of niche and dispersal limitation explain SADs at larger scales. These processes are linked with the degree of conspecific aggregation, informing further attempts to refine and parameterize the statistical theory of sampling SADs.
Dietary niche and population dynamic feedbacks in a novel habitat
Authors: Agashe Deepa , Bolnick Daniel I.
Published: August 2011

Population dynamics and resource use are often intricately connected via density‐dependent intraspecific competition. However, experimental studies of concurrent change in population and resource use dynamics are scarce. In particular, the impact of factors such as genetic diversity, which can affect both population dynamics and competition, remains unexplored. Using stable isotope analysis and periodic population censuses, we quantified both diet and population dynamics in wheat‐adapted Tribolium castaneum (flour beetle) populations provided with an additional novel resource (corn). Populations were initiated with different levels of genetic variation for traits relevant to population growth and resource use (e.g. fecundity and survival).We found that high population size decreased subsequent corn use, and high corn use in turn lowered population size. Surprisingly, we did not detect a significant effect of founding genetic variation on resource niche expansion, although genetic variation increased overall population size and stability. In contrast, dietary niche expansion decreased both population size and stability. Finally, larval and adult niche dynamics were uncorrelated, suggesting that various life stages perceive or respond differentially to intraspecific competition and resource availability. Our experiments indicate that population performance in a novel habitat depends on stage‐specific interactions between resource use, standing genetic variation, and population size.
Intraspecific temperature dependence of the scaling of metabolic rate with body mass in fishes and its ecological implications
Authors: Ohlberger Jan , Mehner Thomas , Staaks Georg , Hölker Franz
Published: August 2011

Metabolism constitutes a fundamental property of all organisms. Metabolic rate is commonly described to scale as a power function of body size and exponentially with temperature, thereby treating the effects of body size and temperature independently. Mounting evidence shows that the scaling of metabolic rate with body mass itself depends on temperature. Across‐species analyses in fishes suggest that the mass‐scaling exponent decreases with increasing temperature. However, whether this relationship holds at the within‐species level has rarely been tested. Here, we re‐analyse data on the metabolic rates of four freshwater fish species, two coregonids and two cyprinids, that cover wide ranges of body masses and their naturally experienced temperatures. We show that the standard metabolic rate of the coregonids is best fit when accounting for a linear temperature dependence of the scaling of metabolic rate with body mass, whereas a constant mass‐scaling exponent is supported in case of the cyprinids. Our study shows that phenotypic responses to temperature can result in temperature‐dependent scaling relationships at the species level and that these responses differ between taxa. Together with previous findings, these results indicate that evolutionarily adaptive and phenotypically plastic responses to temperature affect the scaling of metabolic rate with body mass in fishes.
Field Measurements of Wave Characteristics on a Near‐Horizontal Shore Platform, Mahia Peninsula, North Island, New Zealand
Authors: OGAWA HIROKI , KENCH PAUL , DICKSON MARK
Published: August 2011

Waves are an important process responsible for the initiation and subsequent development of intertidal shore platforms. However, few field studies to date have described wave processes on shore platforms. A field experiment was conducted using an across‐shore array of wave gauges, including a directional sensor, on a near‐horizontal platform at Mahia Peninsula, North Island, New Zealand. Results show that the platform is very efficient in filtering wave energy at gravity wave frequencies (>0.05 Hz), with 40–80% reduction in wave height measured across the 140 m wide platform. By contrast, infragravity waves are present on the platform and increase in magnitude towards the cliff toe. Directional wave analysis indicates that wave reflection is mainly restricted to infragravity wave frequencies, demonstrating the differences in gravity and infragravity wave behaviour on the platform studied. Results indicate that, under fair weather conditions, the role of waves as an agent of cliff toe erosion is likely to be limited at present, although they are probably important for removing sediments accumulated at the cliff toe. The observed increase in infragravity wave energy towards the cliff toe implies that these long‐period waves may be important geomorphic agents on shore platforms.
Under the Magnifying Glass: An Examination of Fundamental Concepts in Mind, Brain, and Education
Authors: Pollack Courtney , Taevs Meghan
Published: August 2011

This special section explicitly introduces aspects of Mind, Brain, and Education (MBE) in order to help those new to the field develop a better understanding of and participate effectively in MBE. Researchers, policy makers, and practitioners who are already active in MBE will also benefit from the varied perspectives on MBE fundamentals to better understand key concepts in the field. The current issue includes two articles concerning communication in MBE: The article by Tina Grotzer outlines potential barriers to understanding scientific work, and the article by Rebecca Martin and Jennifer Groff presents examples of MBE collaborations in action. Subsequent articles will focus on interdisciplinary work and communication among various stakeholders to address meaningful questions in MBE.
Collaborations in Mind, Brain, and Education: An Analysis of Researcher–Practitioner Partnerships in Three Elementary School Intervention Studies
Authors: Martin Rebecca E. , Groff Jennifer S.
Published: August 2011

A reciprocal relationship informing both research and practice is one of the primary goals in the emerging field of Mind, Brain, and Education (MBE), yet the field has little documentation and analysis of such collaborations. In this article, we present case studies of three research–practice partnerships taking place between scientists and educators. By comparing and contrasting these three partnerships we expect to illuminate common characteristics, challenges, and benefits that come with doing MBE work.
Why Right‐Brain Teaching is Half‐Witted: A Critique of the Misapplication of Neuroscience to Education
Authors: Lindell Annukka K. , Kidd Evan
Published: August 2011

Educational tools claiming to use “right‐brain techniques” are increasingly shaping school curricula. By implying a strong scientific basis, such approaches appeal to educators who rightly believe that knowledge of the brain should guide curriculum development. However, the notion of hemisphericity (idea that people are “left‐brained” or “right‐brained”) is a neuromyth that was debunked in the scientific literature 25 years ago. This article challenges the validity of “right‐brain” teaching, highlighting the fact that neuroscientific research does not support its claims. Providing teachers with a basic understanding of neuroscience research as part of teacher training would enable more effective evaluation of brain‐based claims and facilitate the adoption of tools validated by rigorous independent research rather than programs based on pseudoscience.
Early Language Learning and Literacy: Neuroscience Implications for Education
Authors: Kuhl Patricia K.
Published: August 2011

The last decade has produced an explosion in neuroscience research examining young children's early processing of language that has implications for education. Noninvasive, safe functional brain measurements have now been proven feasible for use with children starting at birth. In the arena of language, the neural signatures of learning can be documented at a remarkably early point in development, and these early measures predict performance in children's language and pre‐reading abilities in the second, third, and fifth year of life, a finding with theoretical and educational import. There is evidence that children's early mastery of language requires learning in a social context, and this finding also has important implications for education. Evidence relating socioeconomic status (SES) to brain function for language suggests that SES should be considered a proxy for the opportunity to learn and that the complexity of language input is a significant factor in developing brain areas related to language. The data indicate that the opportunity to learn from complex stimuli and events are vital early in life, and that success in school begins in infancy.
Block Talk: Spatial Language During Block Play
Authors: Ferrara Katrina , Hirsh‐Pasek Kathy , Newcombe Nora S. , Golinkoff Roberta Michnick , Lam Wendy Shallcross
Published: August 2011

Spatial skills are a central component of intellect and show marked individual differences. There is evidence that variations in the spatial language young children hear, which directs their attention to important aspects of the spatial environment, may be one of the mechanisms that contributes to these differences. To investigate how play affects variations in language, parents and children were assigned to 1 of 3 conditions: free play with blocks, guided play, or play with preassembled structures (Study 1). Parents in the guided play condition produced significantly higher proportions of spatial talk than parents in the other two conditions, and children in the guided play condition produced significantly more spatial talk than those in the free play condition. Study 2 established baselines of spatial language during activities not involving spatial materials. Proportions of spatial words were lower than those in any of the conditions of Experiment 1. In sum, interaction with blocks naturally elicits elevated levels of spatial language, especially in the context of guided play, suggesting simple‐to‐execute educational interventions.
Individual Psychological Assessment: A Practice and Science in Search of Common Ground
Authors: Silzer Rob , Jeanneret Richard
Published: August 2011

During the past 30 years, individual psychological assessment (IPA) has gained in use and in value to organizations in the management of human resources. However, even though IPA is considered a core competency for industrial–organizational (I–O) psychology, its practice is not without critics. This article is written not only to address several criticisms of IPA but also to discuss a variety of issues that must be taken into consideration if IPA is to advance as a major component of the I–O scientist–practitioner model. We rely upon a working definition of IPA in general but, when possible, focus on executive assessment in particular, given its high level of complexity and growing popularity. We discuss the effectiveness of assessment practice, including the ongoing statistical versus clinical prediction argument and the difficulties with establishing validity. Although we are confident that IPA has many strong research and practice underpinnings, we also propose some important research questions, training guidelines, and opportunities for assessing psychologists to improve their practices.
High‐throughput molecular identification of fish eggs using multiplex suspension bead arrays
Authors: GLEASON LANI U. , BURTON RONALD S.
Published: August 2011

The location and abundance of fish eggs provide information concerning the timing and location of spawning activities and can provide fishery‐independent estimates of spawning biomass. However, the full value of egg and larval surveys is severely restricted because many species’ eggs and larvae are morphologically similar, making species‐level identification difficult. Recent efforts have shown that nearly all species of fish may be identified by mitochondrial DNA (mtDNA) sequences (e.g. via ‘DNA barcoding’). By taking advantage of a DNA barcode database, we have developed oligonucleotide probes for 23 marine fish species that produce pelagic eggs commonly found in California waters. Probes were coupled to fluorescent microspheres to create a suspension bead array. Biotin‐labelled primers were used to amplify the mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal rRNA genes from individual fish eggs. The amplicons were then hybridized to the bead array, and after the addition of a reporter fluorophore, samples were analysed by flow cytometry with Luminex 100 instrumentation. Probes specifically targeted eggs that are abundant and/or from morphologically indistinguishable species pairs. Results showed that the 33 different probes designed for this study accurately identified all samples when PCR was successful. Suspension bead arrays have a number of benefits over other methods of molecular identification; these arrays permit high multiplexing, simple addition of new probes, high throughput and lower cost than DNA sequencing. The increasing availability of DNA barcode data for numerous fish faunas worldwide suggests that bead arrays could be developed and widely used for fish egg, larval and tissue identifications.
Glaucoma costs in Denmark in treatment naive patients
Authors: Olsen Jens , Berdeaux Gilles , Skov Jesper
Published: August 2011

Purpose:  To describe the costs and providers of glaucoma treatment in Denmark.

Methods:  Analyses were based on National Register data. Glaucoma/OHT patients were identified by their first prescription for glaucoma medication (ATC‐codes) in the Danish Register of Medicinal Product Statistics 2002–2007. Patients had used no glaucoma medication for 6 months. Data for 2007 were sampled cross‐sectionally for a budgetary analysis of glaucoma (ICD10 code) medication and services consumed in the primary and secondary health care services. Patients were categorized according to their number of treatment changes.

Results:  The Danish annual incidence rate of glaucoma was estimated at 1.2 per 1000 adult persons. Thirty‐seven per cent of patients (men 44%, mean age 68 years; women 56%, mean age 71 years) persisted with their initial treatment regimen, 21% had changed to a second regimen, and 43% had experienced ≥3 regimens. Treatment costs increased with the number of sequential regimens. Annual glaucoma costs (health care sector perspective) were €305 for patients under their initial regimen, increasing to €740 with ≥3 regimens. Drug costs accounted for 57% of total cost.

Conclusions:  Drugs represented the major cost of glaucoma, and those costs increased, obviously, with the number of treatment changes.
Visual acuity and contrast sensitivity after posterior lamellar keratoplasty
Authors: Nielsen Esben , Hjortdal Jesper
Published: August 2011

Purpose:  It has previously been reported that patients who suffer from Fuchs’ endothelial dystrophy (Fuchs’ ED) have decreased contrast sensibility threshold. The removal of endothelial guttata by Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) surgery has also been demonstrated to decrease intraocular light scatter and improve contrast thresholds. The purpose of this study was to compare different visual qualities in patients that had undergone DSAEK surgery in one eye while having untreated Fuchs’ dystrophy in the other eye.

Methods:  Thirty‐two eyes of 16 patients with bilateral Fuchs’ ED who had DSAEK surgery performed in one eye were enrolled. Visual acuity at 100% contrast and contrast sensitivity (CS) as evaluated by a modified simulation of the Freiburg Acuity and Contrast Test, was measured in both eyes of each patient.

Results:  Snellen visual acuity improved in treated eyes from 0.66 ± 0.35 (SD) before surgery to 0.38 ± 0.18 after surgery (log MAR units; p < 0.01). In eyes with untreated Fuchs’ dystrophy, visual acuity was 0.46 ± 0.14. In a pairwise comparison, there was no difference in Snellen visual acuity between treated and nontreated eyes (p = 0.12). Contrast sensitivity was significantly better in DSAEK‐treated eyes compared with untreated eyes. Mean log CS in DSAEK‐treated eyes was 1.06 ± 0.25 compared with a mean log CS of 0.84 ± 0.16 in untreated eyes (p < 0.01). Fourteen of 16 patients (88%) reported that vision in their DSAEK‐treated eye had the best visual quality.

Conclusion:  In this study, using a paired design, we demonstrate improved CS in DSAEK‐operated eyes when compared with the other eye that had untreated Fuchs’ ED despite the fact that no difference in visual quality was detected with standard Snellen visual acuity. Contrast sensitivity appears to be superior to normal visual acuity measurements in the evaluation of overall visual quality after DSAEK.
Changes in vaulting of myopic and toric implantable collamer lenses in different lighting conditions
Authors: Lindland Are , Heger Hilde , Kugelberg Maria , Zetterström Charlotta
Published: August 2011

Purpose:  To evaluate the changes in vaulting of myopic and toric Implantable Collamer Lenses (ICLs) in different lighting conditions.

Methods:  Thirty‐seven eyes of 37 patients implanted with a myopic ICL and 26 eyes of 26 patients implanted with a toric ICL were examined using Visante optical coherence tomography (OCT) in photopic (257 lux) and mesopic (2 lux) conditions. Pupil diameter and distance changes between the ICL and adjacent intraocular structures were measured.

Results:  The mean horizontal pupillary diameters in mesopic conditions were 5.3 ± 0.9 (SD) mm. In photopic conditions, a mean decrease of –1.8 ± 0.6 mm [95% confidence interval (95% CI) −2.0 to −1.7; p < 0.0001] was observed. The mean distances between the ICL and the crystalline lens in mesopic conditions were 0.33 ± 0.17 mm. In photopic conditions, a mean decrease of −0.04 ± 0.06 mm (95% CI −0.05 to −0.02; p < 0.0001) in the ICL‐crystalline lens distance was found. There was a −0.02 ± 0.04 mm (95% CI −0.03 to −0.01; p = 0.0022) decrease in the anterior chamber depth and a 0.02 ± 0.06 mm (95% CI 0.002 to 0.032; p = 0.0275) increase in the distance between the cornea and the ICL. We found no difference in the change in vaulting between the two ICLs in different lighting conditions.

Conclusion:  There is a decrease in the central vaulting of myopic and toric ICLs in photopic conditions. This is due to both posterior movement of the ICL and anterior protrusion of the crystalline lens.
Ultrastructural and in vivo confocal microscopic evaluation of interface after Descemet’s Stripping Endothelial Keratoplasty in rabbits
Authors: Chen Minjie , Gong Lan , Xu Jianjiang , Zhu Wenqing , Devine Erin E.
Published: August 2011

Purpose:  To study healing at the donor–recipient interface after Descemet’s Stripping Endothelial Keratoplasty (DSEK) in rabbits by ultrastructural and in vivo confocal microscopic evaluation.

Methods:  The right eye of eight New Zealand White rabbits underwent DSEK. Postoperatively, each rabbit was subjected to routine slitlamp examination daily for 2 weeks and then weekly for 6 weeks. In vivo confocal microscopic evaluation was performed at 1, 2, 4 and 8 weeks. Two rabbits were randomly chosen at 1, 2, 4 and 8 weeks for transmission electron microscopic examination.

Results:  Interface haze decreased with each follow‐up visit. Activated keratocytes and associated cellular processes were evident throughout all the follow‐ups with in vivo confocal microscopy. Highly reflective particles were left at the interface until the end‐point of the study. Upon ultrastructural evaluation, increased rough‐surface endoplasmic reticulum in keratocytes, clefts, folds and retained Descemet’s membrane (DM) were found.

Conclusion:  Clefts lack of adherence at the interface and degenerated keratocyte may make up the highly reflective particles. In addition, retained DM does not appear to affect adhesion and very minimal healing is produced at the DM–stroma smooth interface, which permits better quality of vision in Descemet’s membrane endothelial keratoplasty.
Iranian Registry of Clinical Trials two years on and the timing of registrations
Authors: Solaymani‐Dodaran Masoud , Khalili Davood , Hosseini Hamed , Najafi Laily , Kamali Kourosh , Ranjbar Parvaneh , Tavakoli Hassan , Ostovar Afshin
Published: August 2011

The Iranian Registry of Clinical Trials (IRCT) was established as a primary registry on December 4 2008 and has registered over 1350 trials by June 2011. Many researchers are still unaware of the need for registration of trials before recruiting the first patient and the proportion of retrospectively registered trials is likely to grow until this awareness increases. We sought to investigate the timing of the registrations in IRCT and to explore strategies to overcome this. We used all data in the IRCT database and extracted the date of registration, as well as the dates for the start and the end of recruitment. We categorized trials into 4 groups: those registered before the start of patient enrolment, within 30 days of enrolment, after 30 days but before the end of recruitment, and after the end of recruitment. The proportion of trials in each category was calculated by calendar year.

The number of registered trials increased from 26 in the 3 months leading to 2009 to 181 in 2009, 772 in 2010 and 376 in the first 5 months of 2011 (estimate by end of year = 947). The proportions of trials registered after the end of patient recruitment were 55%, 58% and 62% in 2009, 2010 and 2011 respectively. On average, 6.4% of trials were registered within 30 days from the start of patient recruitment and 27% in the time between then and the end of recruitment.

The rapid increase in the number of registered trials is an indication of strong implementation of the registration policy. This comes partly at the expense of an increased proportion of retrospective registrations. While this may be understandable at the beginning, it is clearly not acceptable and measures should be adopted to increase the proportion of prospectively registered trials and to make trial registration an integral part of the research culture.
Life and Job Satisfaction as Predictors of the Incidence of Diabetes
Authors: Shirom Arie , Toker Sharon , Melamed Samuel , Berliner Shlomo , Shapira Itzhak
Published: August 2011

We studied the hypothesised effects of baseline levels of life satisfaction and of job satisfaction on the incidence of diabetes. Participants were 2,305 apparently healthy men and women who underwent routine health checks at two points in time, about 20 months apart. New cases of diabetes (N = 104) were defined based on fasting glucose value > 125, or glycosylated hemoglobin value > 6.5, or self‐reported physician diagnosis of diabetes and taking medications to treat it. Life satisfaction was measured using the scale constructed by Diener et al. (1985) while job satisfaction was assessed based on the Survey of Working Conditions. In the analyses, we controlled for socio‐demographic predictors, for known physiological and behavioral precursors of diabetes, and for depressive symptoms. There was support for our hypothesis that the higher the baseline levels of life satisfaction, the lower the incidence of diabetes. However, job satisfaction did not predict the incidence of diabetes. We obtained the same results when limiting the analysis to new cases of diabetes based on objective criteria only and when using as predictors both life and job satisfaction. We suggest that life satisfaction could be a protective factor reducing the risk of diabetes.
Knowledge and perceptions regarding oral and pharyngeal carcinoma among adult dental patients
Authors: Park JH , Slack‐Smith L , Smith A , Frydrych AM , O’Ferrall I , Bulsara M
Published: August 2011

Background:  The aim of this study was to assess awareness and knowledge of oral and pharyngeal carcinoma and risk perception for developing the cancer among adult patients attending a major dental centre in Perth. Influence of socio‐demographic factors on awareness, knowledge and perception was ascertained.

Methods:  A random sample of 120 potential participants over the age of 18 who attended the Oral Health Centre of Western Australia between 14 and 18 June 2010 were invited to participate in the survey. A total of 100 participants completed a face‐to‐face interview guided by a questionnaire.

Results:  Seventy‐two per cent of the participants had heard of oral and pharyngeal carcinoma. Sixteen per cent knew that both smoking and drinking increased the risk of oral and pharyngeal carcinoma and 49% knew at least one sign or symptom of the cancer. Language spoken at home, education, and employment influenced cancer awareness and knowledge. Sixty‐two per cent of the participants considered themselves not at risk of developing the cancer.

Conclusions:  The findings suggest that knowledge concerning oral and pharyngeal carcinoma in the community may be limited and educational strategies may be required to improve such knowledge.
Cardiovascular responses to different stages of restorative dental treatment unaffected by local anaesthetic type
Authors: Bispo CGC , Tortamano IP , Rocha RG , Francischone CE , Borsatti MA , da Silva JCB , Medeiros ACR
Published: August 2011

Background:  The aim of this study was to evaluate the cardiovascular effects of maxillary infiltration using 2% lidocaine with 1:100 000 adrenaline, 4% articaine with 1:200 000 adrenaline, and 4% articaine with 1:100 000 adrenaline in different stages during restorative dental procedures.

Methods:  Twenty healthy patients randomly received 1.8 mL of the three local anaesthetics. Systolic blood pressure, average blood pressure, diastolic blood pressure, and heart rate were evaluated by the oscillometric and photoplethysmograph methods in seven stages during the appointment.

Results:  Statistical analysis by ANOVA and Tukey tests of cardiovascular parameters did not show significant differences between the anaesthetic associations. There were significant differences for the parameters among different clinical stages.

Conclusions:  The variation of cardiovascular parameters was similar for lidocaine and articaine with both adrenaline concentrations and showed no advantage of one drug over the other. Cardiovascular parameters were influenced by the stages of the dental procedures, which showed the effect of anxiety during restorative dental treatment.
Oral plasmablastic lymphoma: a case report
Authors: Hewson I
Published: August 2011

Oral plasmablastic lymphoma is a rare malignancy that is associated with patients with HIV or other immunosuppression. This article describes a case of a patient with severe haemophilia A (<1% factor VIII) who had medically acquired HIV and hepatitis C, a CD4+ count of 192 cells/μL and a viral load of 33 200 copies/mL. The patient presented with a two‐month history of a firm swelling around a lower molar. The tooth was removed and the surrounding tissue biopsied. The importance of obtaining an early definitive diagnosis and seeking adequate medical treatment is discussed.
Single use of tetracycline with and without diclofenac sodium as local drug delivery in pocket therapy: a clinico‐microbiological study
Authors: Mohiuddin Khizer , Ravindra Shivamurthy , Ahmed Mohammed Gulzar , Murthy Sarvani , Smitha Byadarahalli Raju
Published: August 2011

Aim:  Local drug delivery is a non‐surgical method in the treatment of periodontitis. Different chemotherapeutic agents are used for local drug delivery; one such agent is tetracycline, a broad‐spectrum antibiotic. Recent studies have also shown that the use of non‐steroidal anti‐inflammatory drugs reduces pro‐inflammatory cytokines and acts as host modulator. Thus, an attempt was made to compare and evaluate the efficacy of tetracycline alone and in combination with diclofenac sodium as a local drug delivery.

Methods:  A total of 36 sites with chronic periodontitis were divided into three groups with 12 sites each (i.e. group A, antibiotics alone; group B, antibiotics in combination with non‐steroidal anti‐inflammatory drugs; and group C, control group). For all the groups, the following parameters (plaque index, papillary bleeding index, probing pocket depth, and microbial analysis) were assessed and statistically analyzed.

Results:  The antibiotic and non‐steroidal anti‐inflammatory drug combination group showed a statistically‐significant improvement in clinical parameters and a shift in microbial flora when compared to the group with antibiotics alone. However, the control group failed to show any statistically‐significant improvement.

Conclusion:  Antibiotics in combination with non‐steroidal anti‐inflammatory drugs are more efficient than using antibiotics alone as local drug delivery for the treatment of periodontal pockets.
Use of triple antibiotic paste in the treatment of large periradicular lesions
Authors: Taneja Sonali , Kumari Manju
Published: August 2011

Microorganisms are the possible source of endodontic lesions. The polymicrobial infection makes the sterilization of the root canal difficult. The following case report describes the non‐surgical endodontic treatment of teeth with a large periradicular lesion. First, an intracanal dressing of calcium hydroxide was given. Since the symptoms did not subside, the treatment protocol was changed. A triple antibiotic paste was used instead for 3 months. On follow up, teeth were clinically asymptomatic and radiographically showed healing of the periradicular lesion. The result of the case show that when most commonly‐used medicaments fail in eliminating the symptoms, then a triple antibiotic paste (metronidazole, ciprofloxacin, and minocycline) can be used clinically in the treatment of teeth with large periradicular lesions.
Cystic variant of calcifying epithelial odontogenic tumor
Authors: Channappa Niranjan Kochli , Krishnapillai Rekha , Rao Jyothi Bellur Madhava
Published: August 2011

The calcifying epithelial odontogenic tumor is a rare benign odontogenic neoplasm of the jaw. Clinically, calcifying epithelial odontogenic tumor manifests as an intraosseous lesion (central type) in the majority of cases (95%). Extraosseous or peripheral lesions account for less than 5% of cases. Calcifying epithelial odontogenic tumor can be associated with an impacted tooth and give a radiographic simulation of dentigerous cyst. Most calcifying epithelial odontogenic tumors are solid in nature, histopathologically, and might have few cyst‐like spaces within them. However, a true cystic calcifying epithelial odontogenic tumor is a rare possibility. We describe a case of a true cystic variant of calcifying epithelial odontogenic tumor in a 30‐year‐old male, which to our knowledge, is only the second reported case.
Plasmacytoma masquerading as an abscess
Authors: Nanda Kanwar Deep Singh , Bhargava Deepak , Sharma Bhudev , Dave Aparna
Published: August 2011

Plasma cell neoplasia is a lymphoid neoplastic proliferation of B cells and has been classified as multiple myeloma, solitary plasmacytoma, and extramedullary plasmacytoma. Extramedullary plasmacytoma is defined as neoplastic proliferation of plasma cells in the soft tissue. Extramedullary plasmacytoma of the head and neck is very uncommon tumors, representing approximately 0.4% of all head and neck malignancies; amongst them, plasmacytoma of the maxilla is extremely rare. We present a case of a 70‐year‐old male with swelling on the right middle third of the face, mimicking an abscess, but proven to be extramedullary plasmacytoma. This report discusses the clinical, radiographic, histological, and immunohistochemical features of extramedullary plasmacytoma.
Turbulent Mixed Convection Inside a Vertical Tube With Wetted Wall
Authors: Chesneau X. , Abide S. , Zeghmati B.
Published: August 2011

The authors present a numerical investigation of turbulent mixed convection inside a wetted—wall tube. The mixture air and water vapor flows downwards the vertical tube. Turbulent momentum, heat and mass transfer equations combined with a low Reynolds number model are discretized by using the finite volume method. The algebraic system equations deduced from this discretization are solved with the Thomas and Gauss algorithms. Results show that the evaporative cooling of the wetted wall and the air flow through the tube can be produced by low heat flux applied to the tube wall.
Effect of Cutoff Radius on the Surface Tension of Nanoscale Bubbles
Authors: Cosden Ian A. , Lukes Jennifer R.
Published: August 2011

Molecular dynamics simulations are performed to calculate the surface tension of bubbles formed in a metastable Lennard–Jones (LJ) argon fluid. The calculated normal and transverse pressure components are used to compute a surface tension which is compared to the surface tension computed from the Young–Laplace equation. Curvature effects on surface tension are investigated by performing various sized simulations ranging from 6912 to 256,000 LJ particles. The computed surface tension values differ depending on the calculation method for the smaller systems studied but the methods converge as the system size increases. Surface tension calculations on small bubbles may not be appropriate since the liquid farthest from the interface has yet to achieve the pressure profile of a homogeneous fluid. Density profiles, pressures, and calculated surface tensions are shown to have a strong dependence on the choice of the interaction cutoff radius. A cutoff radius of 8σ, significantly larger than that commonly used in the literature, is recommended for accurate calculations in liquid–vapor systems.
Three-Dimensional Numerical Study on Freezing Phase Change Heat Transfer in Biological Tissue Embedded With Two Cryoprobes
Authors: Zhao Fang , Chen Zhenqian
Published: August 2011

Biological tissues undergo complex phase change heat transfer processes during cryosurgery, and a theoretical model is preferable to forecast this heat experience. A mathematical model for phase change heat transfer in cryosurgery was established. In this model, a fractal treelike branched network was used to describe the complicated geometrical frame of blood vessels. The temperature distribution and ice crystal growth process in biological tissue including normal tissue and tumor embedded with two cryoprobes were numerically simulated. The effects of cooling rate, initial temperature, and distance of two cryoprobes on freezing process of tissue were also studied. The results show that the ice crystal grows more rapidly in the initial freezing stage (<600 s) and then slows down in the following process, and the precooling of cryoprobes has no obvious effect on freezing rate of tissue. It also can be seen that the distance of 10 mm between two cryoprobes produces an optimal freezing effect for the tumor size (20 mm × 10 mm) in the present study compared with the distances of 6 mm and 14 mm. The numerical results are significant in providing technical reference for application of cryosurgery in clinical medicine.
Elastoplastic Stress Analysis and Residual Stresses in Cylindrical Bar Under Combined Bending and Torsion
Authors: Kobelev V.
Published: August 2011

The excessive stresses during the coiling of helical springs could lead to breakage of the rod. Moreover, the high level of residual stress in the formed helical spring reduces considerably its fatigue life. For the practical estimation of residual and coiling stresses in the helical springs the analytical formulas are necessary. In this paper the analytical solution of the problem of elastic–plastic deformation of cylindrical bar under combined bending and torsion moments is found for a special nonlinear stress–strain law. The obtained solution allows the analysis of the active stresses during the combined bending and twist. Moreover, the residual stresses in the bar after springback are also derived in closed analytical form. The results of this analysis are applied to the actual engineering problem of determination of stresses during the manufacturing of helical coiled springs. A practically important example, describing the manufacturing of helical coiled spring is worked out to illustrate the simplicity achieved in determining the plasticization process and residual stresses. The obtained results match the reported measured values. The developed method does not require numerical simulation and is perfectly suited for programming of coiling machines, estimation of loads during manufacturing of cold-wounded helical springs and for dimensioning and wear calculation of coiling tools.
Machine Recognition of Laser Reflection From Gas Metal Arc Weld Pool Surfaces
Authors: Wang ZhenZhou , Zhang YuMing , Ma XiaoJi
Published: August 2011

The reflection of projected laser lines may be used to determine the three-dimensional geometry of the reflecting weld pool surface. However, for gas metal arc welding (GMAW), the transfer of the droplets into the weld pool makes the weld pool surface highly dynamic and fluctuating. The position and geometry of the local reflecting surface, which intercepts and reflects the projected laser changes rapidly. As a result, the reflection rays change their trajectories rapidly. The contrast of laser reflection with the background is much reduced and methods are needed to extract laser reflection from low contrast images. To this end, an image quality measurement method is proposed based on the number of the edge points to determine if an image may be further processed. The image to be processed is then modeled as a superposition of the laser reflection and arc radiation background. Methods have been proposed to remove the uneven distribution of the arc radiation background from the image, such that a global threshold is possible to segment the laser reflection lines. The set of the laser line points are then clustered to form separate laser lines. These laser lines are then modeled and the parameters in the models are used to validate each modeled line. Processing results verified the effectiveness of the proposed methods/algorithms in providing laser lines from low contrast images that are formed by laser reflection from a high dynamic gas metal arc weld pool surface.
Electroplastic Modeling of Bending Stainless Steel Sheet Metal Using Energy Methods
Authors: Salandro Wesley A. , Bunget Cristina , Mears Laine
Published: August 2011

Automotive manufacturers are continuously striving to meet economic demands by designing and manufacturing more efficient and better performing vehicles. To aid this effort, many manufacturers are using different design strategies such to reduce the overall size/weight of certain automotive components without compromising strength or durability. Stainless steel is a popular material for such uses (i.e., bumpers and fuel tanks), since it possesses both high strength and ductility, and it is relatively light for its strength. However, with current forming processes (e.g., hot working, incremental forming, and superplastic forming), extremely complex components cannot always be easily produced, thus, limiting the potential weight-saving and performance benefits that could be achieved otherwise. Electrically-assisted manufacturing (EAM) is an emerging manufacturing technique that has been proven capable of significantly increasing the formability of many automotive alloys, hence the “electroplastic effect”. In this technique, electricity can be applied in many ways (e.g., pulsed, cycled, or continuous) to metals undergoing different types of deformation (e.g., compression, tension, and bending). When applied, the electricity lowers the required deformation forces, increases part displacement or elongation and can reduce or eliminate springback in formed parts. Within this study, the effects of EAM on the bending of 304 Stainless Steel sheet metal will be characterized and modeled for different die widths and electrical flux densities. In previous works, EAM has proven to be highly successful on this particular material. Comparison of three-point bending force profiles for nonelectrical baseline tests and various EAM tests will help to illustrate electricity’s effectiveness. An electroplastic bending coefficient will be introduced and used for modeling an electrically-assisted (EA) bending process. Additionally, the springback reductions attained from EAM will be quantified and compared. From this work, a better overall understanding of the effects and benefits of EAM on bending processes will be explained.
Dynamic Process Modeling for Rotary Ultrasonic Machining of Alumina
Authors: Wu Jiaqing , Cong Weilong , Williams Robert E. , Pei Z. J.
Published: August 2011

Rotary ultrasonic machining (RUM) is a hybrid machining approach that combines two material removal mechanisms, namely, diamond grinding and ultrasonic machining. This paper presents the results of dynamic process modeling for RUM of alumina, as currently available literature mainly focuses on static parametric relationships. A stochastic modeling and analysis technique called data dependent systems (DDS) was used to study RUM generated surface profiles and cutting force signals. Variations in the data sets of surface profiles, for the entrance and exit segments of machined holes and for that of machined rods, and cutting force signals were modeled and decomposed to gain insight into the RUM process mechanism. The DDS wavelength decomposition of the surface profiles suggested that the major characteristic root wavelength had a positive correlation with feed rate, and the wavelength magnitude may be linked to the grain size of the workpiece material. The roughness of machined surfaces increased as the tool moved deeper due to reduced flushing efficiency. Surfaces on the machined rods were less sensitive to the input variables than the hole surfaces. Moreover, spindle speed and feed rate affected the cutting force significantly.
Emission mechanism of high current density scandia-doped dispenser cathodes
Authors: Wang Yiman , Wang Jinshu , Liu Wei , Zhang Xizhu , Li Lili
Published: August 2011

The emission mechanism of scandia-doped dispenser (SDD) cathodes is characterized based on systematic investigation of microstructure, surface behavior, evaporation, and emission. High current density SDD cathodes have been developed in recent years to meet the requirements of advanced vacuum electron devices. Space charge limited current densities of over 100 A/cm2 have been reliably reached at a temperature of 950 °Cb. SDD cathodes are composed of a tungsten matrix with submicron structure and uniformly dispersed materials containing Sc, Ba, Ca, Al, and O as nanosized particulates in the matrix. The authors conclude that the copious electron emission from this cathode type results from a layer of Ba–Sc–O on W formed after activation on top of the matrix. This layer is about 100 nm thick and maintains a stable composition over its lifespan. Its emission can be explained in terms of a semiconductor layer with characteristics that differ from a metal-like emission model. The Ba–Sc–O layer is formed by codiffusion of Sc, Ba, and O (generated inside the W-matrix) to the surface of the W-matrix during activation. Furthermore, this layer guarantees a low evaporation rate of emission-relevant materials and thus enables a longer lifespan.
Electrical characteristics of buried-Pt Schottky contacts on thin InP/InAlAs heterostructures
Authors: Shin Seung Heon , Song Jong-In , Jang Jae-Hyung , Park Sang-Duk , Bae Jeong-Woon , Yeom Geun-Young , Kim Tae-Woo
Published: August 2011

Schottky diodes were fabricated on the InP/InAlAs heterostructures where the thickness of the InP ranges from 0 to 7 nm. A Ne-based atomic layer etching technique was utilized for precise control of the thickness of the InP layer. After removing the part of the InP layer, Pt/Ti/Pt/Au multilayer metallization was evaporated to form a Schottky contact. Thermal annealing was then carried out to drive Pt into the device layer. The electrical characteristics of the Schottky diodes were analyzed to determine the effect of a thin InP layer on the performance of the Schottky diodes. Transmission electron microscopy (TEM) was also utilized to investigate the diffusion of the metal into the semiconductor heterostructures. The experimental results show that the 7-nm-thick Pt can pass through the 4-nm-thick InP layer and reach the InAlAs layer. A Schottky junction was effectively formed within InAlAs layer when the thickness of the InP layer was equal or less than 4 nm for the 7-nm-thick Pt bottom layer.