bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrothermal alteration and tectonic evolution of an intermediate‐ to fast‐spreading back‐arc oceanic crust: Late Ordovician Solund‐Stavfjord ophiolite, western Norway
Authors: Fonneland‐Jorgensen Hege , Furnes Harald , Muehlenbachs Karlis , Dilek Yildirim
Published: December 2005

Abstract  The Solund‐Stavfjord ophiolite complex (SSOC) in western Norway represents a remnant of the Late Ordovician oceanic lithosphere, which developed in an intermediate‐ to fast‐spreading Caledonian back‐arc basin. The internal architecture and magmatic features of its crustal component suggest that the SSOC has a complex, multistage sea floor spreading history in a supra‐subduction zone environment. The youngest crustal section associated with the propagating rift tectonics consists of a relatively complete ophiolite pseudostratigraphy, including basaltic volcanic rocks, a transition zone between the sheeted dyke complex and the extrusive sequence, sheeted dykes, and high‐level isotropic gabbros. Large‐scale variations in major and trace element distributions indicate significant remobilization far beyond that which would result from magmatic processes, as a result of the hydrothermal alteration of crustal rocks. Whereas K2O is strongly enriched in volcanic rocks of the extrusive sequence, Cu and Zn show the largest enrichment in the dyke complex near the dyke–volcanic transition zone or within this transition zone. The δ18O values of the whole‐rock samples show a general depletion structurally downwards in the ophiolite, with the largest and smallest variations observed in volcanic rocks and the transition zone, respectively. δ18O values of epidote–quartz mineral pairs indicate 260–290°C for volcanic rocks, 420°C for the transition zone, 280–345°C for the sheeted dyke complex and 290–475°C for the gabbros. The 87Sr/86Sr isotope ratios show the widest range and highest values in the extrusive rocks (0.70316–0.70495), and generally the lowest values and the narrowest range in the sheeted dyke complex (0.70338–0.70377). The minimum water/rock ratios calculated show the largest variations in volcanic rocks and gabbros (approximately 0–14), and generally the lowest values and range in the sheeted dyke complex (approximately 1–3). The δD values of epidote (−1 to −12‰), together with the δ18O calculated for Ordovician seawater, are similar to those of present‐day seawater. Volcanic rocks experienced both cold and warm water circulation, resulting in the observed K2O‐enrichment and the largest scatter in the δ18O values. As a result of metal leaching in the hot reaction zone above a magma chamber, Zn is strongly depleted in the gabbros but enriched in the sheeted dyke complex because of precipitation from upwelling of discharged hydrothermal fluids. The present study demonstrates that the near intact effect of ocean floor hydrothermal activity is preserved in the upper part of the SSOC crust, despite the influence of regional lower greenschist facies metamorphism.
Origin of layering in cumulate gabbros in the Oman ophiolite: Insights from magnetic susceptibility measurements in the Wadi Sadm area
Authors: Kawamura Kiichiro , Hosono Takahiro , Allawati Huda Mohamed , Ogawa Yujiro , Taniguchi Hidetsugu
Published: December 2005

Abstract  Magnetic susceptibility and the anisotropy of magnetic susceptibility were measured on an 800‐cm‐thick succession of cumulate gabbro in the Sadm area of the Oman ophiolite. The section contained three distinct cumulate units. The susceptibility tends to decrease upward in each from a melanocratic layer (several tens of centimeters thick) to a leucocratic layer (a few meters thick). The susceptibility decreases in accordance with the decreasing number of magnetite grains, which are the alteration product mainly of olivine minerals. This suggests the cyclic downward accumulation of olivine in the cumulate gabbro. The apparent strain deduced from the patterns of magnetic and grain fabrics was the result mostly of simple shear, so that the layering of gabbro is understood to be formed primarily by a crystal cumulus process followed by simple shear deformation.
ADDICTION AND AUTONOMY: CAN ADDICTED PEOPLE CONSENT TO THE PRESCRIPTION OF THEIR DRUG OF ADDICTION?
Authors: FODDY BENNETT , SAVULESCU JULIAN
Published: December 2005

It is often claimed that the autonomy of heroin addicts is compromised when they are choosing between taking their drug of addiction and abstaining. This is the basis of claims that they are incompetent to give consent to be prescribed heroin. We reject these claims on a number of empirical and theoretical grounds. First we argue that addicts are likely to be sober, and thus capable of rational thought, when approaching researchers to participate in research. We reject behavioural evidence purported to establish that addicts lack autonomy. We present an argument that extrinsic forces must be irresistible in order to make a choice non‐autonomous. We argue that heroin does not present such an irresistible force. We make a case that drug‐oriented desires are strong regular appetitive desires, which do not compromise consent. Finally we argue that an addict's apparent desire to engage in a harmful act cannot be construed as evidence of irrational or compulsive thought. On these arguments, a sober heroin addict must be considered competent, autonomous and capable of giving consent. More generally, any argument against legalisation of drugs or supporting infringement of the liberty of those desiring to take drugs of addiction must be based on considerations of harm and paternalism, and not on false claims that addicts lack freedom of the will.
Inter‐Firm R&D Networks: the Importance of Strategic Network Capabilities for High‐Tech Partnership Formation1
Authors: Hagedoorn John , Roijakkers Nadine , Van Kranenburg Hans
Published: December 2005

We examine the role of different network capabilities of companies that influence the formation of R&D partnerships in pharmaceutical biotechnology. Strategic network capabilities, specifically centrality‐based capabilities and the efficiency with which companies choose their partners, are found to facilitate the formation of new partnerships. Unlike general experience with partnering, these strategic network capabilities play a crucial role in enabling companies to continue to interact with other companies through partnerships in a complex network setting.
It's the Culture, Stupid! New Labour's Progressive Consensus
Authors: LEGGETT WILL
Published: December 2005

For New Labour to achieve the 'progressive consensus' to which it aspires, it needs to develop a transformative, cultural politics. This would engage in a battle of hearts and minds with the electorate, seeking to shape its preferences rather than accommodating them. Much of the accumulated criticism of New Labour focuses on its failure to develop an overarching political narrative to fulfil this task. However, critics have also shown that New Labour does have a definite vision of the type of society and individual it is constructing in the face of social change. Unfortunately for progressives, this is based on an image of the acquisitive individual, culturally conservative community and a fatalistic understanding of modernisation. Entrenching a progressive consensus requires a political strategy that resonates with contemporary experiences of social change, while showing how it can be steered in more progressive directions.
Can the Democrats Win Again?
Authors: AVERY LAWRENCE
Published: December 2005

After losing two successive elections, debate has raged within the Democratic party over how to win back power without comprising the principles which the party has long stood for. This article explores the reasons why the Democrats were unable to defeat George W. Bush in 2004, despite the numerous problems of the incumbent' first term, and asks what lessons the Democrats can learn from their defeat. The second half of the article focuses on what issues and policies the Democrats should concentrate and what strategies the party should adopt in order to improve its image and broaden its popular appeal ahead of the 2008 election.
Managing Regulatory Risks and Defining the Parameters of Blame: A Focus on the Australian Prudential Regulation Authority
Authors: BLACK JULIA
Published: December 2005

Risk‐based regulation is a new arrival in the lexicon of risk and regulation. Regulators in Australia, Canada, and the UK have begun developing systems and processes to assess the probability and impact of compliance failures by regulated firms, and to adjust their relationship with firms accordingly. This article explores the motivations for, and key elements of, the risk‐based frameworks of one of those regulators, the Australian Prudential Regulation Authority (APRA). It broadens out from this case study to argue first, that risk‐based regulation goes hand in hand with the technique of “meta” regulation, the regulation of the firm's own internal self regulation, and will both fuel and be fueled by any trend towards the latter. Second, it argues that risk‐based frameworks are not risk‐free: whilst they seek to manage risks they inevitably introduce their own. Third, risk‐based regulatory frameworks have the potential both to expose and obscure key sociopolitical and socioeconomic choices as to the amount or types of regulatory failures that an agency will tolerate, and which in effect it is requiring society to tolerate. “Risk based frameworks” are attempt to define what are acceptable “failures” and what are not, and thus to define the parameters of blame.
The US Dollar and the Trade Deficit: What Accounts for the Late 1990s?*
Authors: Hunt Benjamin , Rebucci Alessandro
Published: December 2005

Based on a version of the IMF's global economy model set up to analyse macroeconomic interdependence between the United States and the rest of the world, this paper asks to what extent accelerating productivity growth in the United States may have contributed to the US real exchange rate appreciation and the trade balance deterioration witnessed in the second half of the 1990s. The paper concludes that productivity is only part of this story. A portfolio preference shift in favour of US assets, possibly triggered by faster productivity growth, and some uncertainty and learning about the persistence of both shocks are needed to match the data more satisfactorily.
Poly (ɛ‐caprolactone) Grafted With Nano‐structured Chitosan Enhances Growth of Human Dermal Fibroblasts
Authors: Chung Tze‐Wen , Wang Yen‐Zen , Huang Yi‐You , Pan Chin‐I , Wang Shoei‐Shen
Published: December 2005

Abstract:  Polyester films are modified with their bioactivity for tissue engineering by grafting a nano‐structured bioactive material, nano‐structured chitosan (nano‐CS), on a model polymer, poly (ɛ‐caprolactone) (PCL). The nano‐CS was duplicated using a solvent‐etched PCL mold and then grafted onto PCL using a selected solvent. The structure of the nano‐CS/PCL surface was characterized using an atomic force microscope to observe the topography and determine the roughness. The centerline average roughness, Ra, of the surface of the nano‐CS/PCL film is 106.0 ± 4.0 nm whereas that of the surface of the CS‐grafted PCL film (CS/PCL) is 3.6 ± 0.4 nm. The latter is therefore very smooth. CS is known to swell following hydration, so the Ra values were determined again after immersion for 12 h in phosphate buffered saline. Although the centerline average roughness of the nano‐CS/PCL was lower, it still markedly exceeded that of the CS/PCL film. Cells grown on nano‐CS/PCL, CS/PCL, nano‐structured PCL (nano‐PCL), and PCL films were observed by fluorescent staining and analyzed by MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazolium bromide) viability assay following 3 and 7 days of culture, to evaluate the effects of the design on the growth of fibroblasts. The viability assay of the cells reveals that the growth rate of cells on both CS/PCL and nano‐CS/PCL films significantly exceeds (P < 0.001) those of PCL and nano‐PCL films on both cultural days. Additionally, the growth rate and proliferation of fibroblasts on nano‐CS/PCL films significantly exceed (P < 0.001) those on CS/PCL films after both periods of culturing, suggesting that the bioactive surface following a nano‐structured treatment promotes the growth rate of cells. However, nano‐PCL films do not have the same effects as nano‐CS/PCL films do. In conclusion, a novel biomaterial, nano‐CS/PCL, is developed by grafting a nano‐structured bioactive surface, CS, onto the PCL surface to promote the the growth rate of fibroblasts. This work elucidates a new concept for designing films or scaffolds for tissue engineering—the grafting of nano‐structured bioactive biomaterials to the films or scaffolds to promote the growth of cells.
Effects of the anti‐androgen finasteride on 5α‐reductase activity in human gingival fibroblasts in response to minocycline
Authors: Soory M. , Virdi H.
Published: December 2005

Abstract. In addition to their antimicrobial properties, tetracyclines have anti‐inflammatory and pro‐anabolic effects on the reparatory potential of connective tissue and bone. The physiologically active androgen 5α‐dihydrotestosterone(DHT) implicated in matrix synthesis is formed in gingivae from androgen substrates. The aim of this investigation is to study the androgen metabolic response of gingivae to minocycline, in the presence or absence of the anti‐androgen finasteride. Chronically inflamed gingival tissue derived from 12 subjects aged 30–50years and passaged fibroblasts derived from this source, were used for the experiments. Duplicate incubations were performed in Eagle's MEM with 14C‐testosierone/14C‐4‐androstenedione in the presence or absence of minocycline (5–60 μg/ml) or finasteride for 24 h. The androgen substrate 14C‐testosteronewas metabolised mainly to DHT and 4‐androstenedione, while 14C‐4‐andros‐tenedione was converted mainly to DHT and testosterone. Minocycline at 20–30 μg/ml stimulated the formation of these metabolites from both substrates by 13–25%. In the tissue incubations there were 3‐ and 2‐fold increases in DHT and 4‐androstenedione formation (n=12; p<0.01). The anti‐androgen finasteride caused significant inhibition of 5α‐reductase activity on both substrates at 0.1 & 1.0 μg/ml with total inhibition at 10 & 50 μg/ml (n=3; p<0.01). Minocycline‐induced stimulation of 5α‐reductase activity was also inhibited by finasteride (n=4; p<0.02). Since finastcride inhibition of 5α‐reductase activity is specific for the type 2 isoenzyme associated with anabolic functions of target tissue, this enzyme activity may contribute to some of the cited anabolic tissue responses to minocycline.
The inhibitory effect of combining chlorhexidine and hydrogen peroxide on 3‐day plaque accumulation
Authors: Dona B. L. , Gründemann L. J. M. M. , Steinfort J. , Timmerman M. F. , van der Weijden G. A.
Published: December 2005

Abstract. In a blind, randomised, 4‐cell, cross‐over study, the effect of rinsing with a perborate solution (1.9 g sodiumperborate‐monohydrate dissolved in 30 ml water bocasan. Oral‐B$$) on the vivo plaque‐inhibiting effect of 0.12$$ chlorhexidme (Oral‐B$$) was examined. After a thorough professional prophylaxis including interdental cleaning. 12 subjects started to rinse according to 4 different regimens: regimen (C‐P‐C): chlorhexidine in the morning, perborate at noon and chlorhexidine in the evening: regimen (CP‐CP): chlorhexidine immediately followed by perborate in the morning and in the evening: regimen (PC‐PC): perborate immediately followed by chlorhexidine in the morning and in the evening: regimen (C‐C): chlorhexidine in the morning and in the evening No further oral hygiene measures were allowed for the next 72 h. After 72 h. the subjects were scored for plaque, and a washout period of 4 days followed: cross‐over was randomly assigned according to a Latin square design. Following this procedure, all subjects went through all 4 regimens. The regimens C‐P‐C and PC‐PC resulted in significantly lower plaque‐scores. 0.27 and 0.28 respectively, than regimen C‐C (0.40). For the regimen CP‐CP, the plaque‐score was 0.28. which was not significantly different from the C‐C regimen. The results suggest a positive interaction between chlorhexidine and hydrogen peroxide. Rinsing with a combination of 0.12% chlorhexidine (Oral‐B$$) and a perborate solution (bocasan Oral‐B$$) can result in more effective short‐term plaque growth inhibition than rinsing with chlorhexidine alone.
Local delivery of chemotherapeutic agents in periodontal therapy: Has its time arrived?1
Authors: Finkelman Richard D. , Williams Ray C.
Published: December 2005

Abstract. The concept of locally‐delivering chemotherapeutic agents to the periodontal pocket as a method to treat periodontal disease has been studied for over 20 years. A number of locally‐delivered chemotherapeutic agents in periodontal therapy are either currently available or under investigation. Clinical efficacy derives from sustained‐release technology to maintain an effective concentration of drug within the periodontal pocket for a clinically relevant length of time. Studied drugs have mainly been antimicrobials, both antibiotics and antiseptics. Most agents have been tested as adjuncts to scaling and root planing: a few have been studied as stand‐alone monotherapies. Collectively, the data indicate that the use of locally‐delivered antimicrobials as adjuncts results in a significant increase in the reduction of probing depth compared with scaling and root planing alone. In other trials, results in reducing probing depth following the use of stand‐alone locally‐delivered antimicrobials have been equivalent to those of scaling and root planing over a specified time. This Symposium was organized to present the current slate‐of‐the‐art with regard to the use of locally delivered antimicrobials in the treatment of periodontal disease, 5 experts in the field who have had considerable experience in studying locally‐delivered antimicrobials presented data. These speakers reviewed the clinical findings regarding efficacy of 5 different antimicrobial agents. An ensuing panel discussion was to consider treatment recommendations for locally‐delivered antimicrobials.
Local delivery of terracycline: from concept to clinical application*
Authors: Tonetti Mauizio S.
Published: December 2005

Abstract. This manuscript reviews the development over the last 20 years of the evidence supporting the clinical application of a controlled delivery device for the treatment of human periodontitis. The device is a monolithic ethylene vinyl‐acetate fibre loaded with 25% w/w tetracycline HCl (tetracycline fibre). It releases tetracycline at a steady state rate of 2μg/cm‐h and results in the maintenance of essentially constant, highly‐effective concentrations of tetracycline at the site of action. A series of controlled, randomised, single‐blind, phase‐III clinical trials including a total of 463 patients has indicated that (1) tetracycline fibres result in significantly better outcomes than the scaling and root planning positive control: (2) combination of tetracycline fibres with subgingival mechanical debridement results in significant improvement over debridement alone. Evidence from these studies had led to approval of this treatment modality by the US Food and Drug Administration and by the European Union Regulatory Bodies. A clinical usage study involving 2711 subjects treated by 68 clinicians in Europe and North American indicated that the magnitude of the observed clinical outcomes is clinically relevant and that adverse events were rarely observed. A variety of clinical investigations aimed at the optimal incorporation of tetracycline fibres in a treatment strategy provided guidance in case selection. Cost of therapy and concerns of unnecessary usage of antibiotics should be considered. It is nonetheless concluded that combination of tetracycline fibres with mechanical debridement represents a documented treatment alternative, the application of which may offer clinical benefits to many patients.
The effectiveness of different root debridement modalities in open flap surgery
Authors: Huerzeler M.B. , Einsele F.T. , Leupolz M. , Kerkhecker U. , Strub J. R.
Published: December 2005

Abstract. It is unclear what degree of roughness or smoothness result from use of hand instruments alone in comparison to the use of hand instruments in combination with other aids and how it may effect the grade of cleanliness. The aim of this study was to determine in vivo whether the combination of hand instruments with other aids can increase the effectiveness of root debridement. 11 patients with holpless 4 mandibular incisors were involved in this study. After elevating a lingual and buccal mucoperiosteal flap, the 4 incisors were randomly treated with either: (1) no treatment (control); (2) 5‐niin scaling (method 1); (3) 4‐min scaling and 1‐min instrumentation with a perio‐diamond bur (15 μm) (method 2); (4) 3‐min scaling, 1‐min instrumentation with a perio‐diamond bur (15 μm) and 1 min with an air abrasive system (method 3). The cleanliness of the surface was determined using the method of Eschler and ‐Rapley. The degree of roughness (Ra and Rt) were measured with a laser beam (computer supported optical surface sensor system). In addition, an SEM analysis was performed. With regard to the remaining calculus (surface cleanliness), method 3 yielded significantly better results than the other 2 methods. The roughness analyses also exhibited that method 3 is superior to methods 1 and 2. The qualitative results of the SEM investigations demonstrated the most homogenous and smooth surfaces with method 3. Root debridement in vivo was most significant using a combination of different treatment modalities (i. e., curettes, perio‐diamond bur and air abrasive system).
Long‐term effects of root‐resective therapy in furcation‐involved molars
Authors: Carnevale G. , Pontoriero R. , di Febo G.
Published: December 2005

Abstract. The present investigation was designed to evaluate the long‐term effect of root‐resective therapy in the treatment of furcation‐involved molars. The patient sample included 72 patients, 21–62 years of age, who presented periodontal lesions in the posteriors segments of the mouth including furcation involvement of various degrees. After an initial examination, each patient was subjected to a series of full‐mouth scaling and root planing. They were recalled 1–3 months later for a presurgical examination and subsequently underwent the corrective phase of therapy. During the surgical procedure, the furcation‐involved teeth were subjected to root‐resective therapy in conjunction with osseous recontouring and apically positioned flaps (test sites). A surgical procedure identical to the test procedure was performed in the non‐furcation‐involved teeth (control sites) with the exception of the root resection. At the completion of the active phase of treatment, 175 test and 175 control sites were available for the study. After a period of 6 months of healing and plaque control supervision following surgical procedures, the patients were recalled for a baseline examination. They were then enrolled in a maintenance program including professional tooth cleaning every 2–6 months. The patients were re‐examined 3, 5 and 10 years post‐operativety. The results of the assessments demonstrated that the survival rate, during the 10‐year period of observation, reached 93% at test and 99% at control sites. The positive treatment outcome at the root‐resected, furcation‐involved teeth as well as al non‐furcation‐involved teeth was probably the consequence of the reestablishment of a tissue morphology favorable for oral hygiene and careful plaque control by the patients.
The rôle of a dentine‐bonding agent in reducing cervical dentine sensitivity
Authors: Ide M. , Morel A. D. , Wilson R. F. , Ashley F. P.
Published: December 2005

Abstract. This double‐blind split‐mouth trial with 16 adult patients investigated the ability of a dentine bonding agent (DBA) to reduce cervical dentine sensitivity. Following stimulation of pairs of teeth by conventional tactile and air blast stimuli, together with controlled evaporative and cold fluid stimuli, sensitivity was recorded using tactile threshold, visual‐analogue scale (VAS) and short‐form McGill pain questionnaire (SFMPQ), prior to and 1 week following treatment with DBA. Prior to assessment, subjects recorded their perceived overall sensitivity using VAS and SFMPQ. Application of each stimulus was separated by 10 min. Sensitivity was recorded by a clinician blinded to the treatment status of each tooth. The control tooth was treated by applying DBA to coronal enamel. Dietary information was collected after the post‐treatment assessment. There was a significant (p<0.05) improvement in tactile threshold and air flow and air blast VAS scores, together with reductions in sensitivity to evaporative stimuli when assessed by SFMPQ. Treatment response was not influenced by the subjects’age, gender, diet, use of fluoride‐containing or silica‐based toothpastes or fluoride mouthwashes, or a history of previous sensitivity treatment. It is concluded that topical application of DBA is an effective way to reduce cervical dentine sensitivity.
Flossing behaviour in English adolescents
Authors: Macgregor I. D. M. , Balding J. W. , Regis D.
Published: December 2005

Abstract. The aim of this study was to investigate the relation between flossing behaviour and other health, cleanliness and social behaviours in adolescents. Data from a survey of 41142, 12–16‐year‐old children from 244 secondary schools throughout England were analysed to obtain information about flossing frequency, dental attendance and recalled advice about flossing, and some general cleanliness and social behaviours. Subjects completed a questionnaire, anonymously, in class during normal school hours. Flossing frequency was found to change with age, its use becoming less frequent from age 12 through age 16 years. There was a significant relationship between flossing frequency and the time since the last dental attendance, the more recent attenders flossing more frequently, 6% of subjects recalled receiving advice about flossing at their last dental attendance and higher proportions of those who used floss recalled such advice, compared with non‐flossers. Flossing frequency was also found to correlate positively with frequencies of washing hands after visiting the lavatory and bathing, and having a current friend of the opposite gender. There was only a small association between smoking habit and flossing, and only in school years 8 and 10: subjects most committed to smoking used floss slightly more frequently than those who did not smoke. Factor analysis showed evidence of gender differences in perceptions of flossing. Males equated use of floss with health‐related behaviours while females associated flossing more with cleanliness behaviours. This finding is consistent with gender differences in toothbrushing behaviour reported in previous studies. The present study provides further insights into the history of dental flossing.
Instrumentation of furcation with modified sonic sealer inserts A study on manikins (II)
Authors: Kocher Thomas , Tersic‐Orth Bärbel , Plagmann Hans‐Christian
Published: December 2005

Abstract. We developed a sonic sealer tip with an ellipsoid diamond‐coated bud and contra‐angulated shafts to overcome problems resulting from furcation anatomy. In this study, extracted molars were instrumented in a dummy model without any replicated soft tissues using 3 different instrumentation methods (i) curettes, (ii) diamond‐coated sonic sealer tips with normal handle and (iii) diamond‐coated sonic sealer tips in 2 handles with varying power levels. 15 extracted upper and lower molars were instrumented using each of the 3 instrumentation types. Following debridement, loss of substanee and % of furcation area instrumented were assessed. In both upper and lower molars, significantly more surface area was instrumented in one instrumentation run with diamond‐coated tips than with curettes. Substance loss was greater with diamond‐coated lips than with hand instruments. In conclusion, an effective debridement of the furcation roof seems only possible with odontoplasty. Clinical evaluation of this approach to root debridement is needed.
Effect of mechanical toothbrush stimulation on gingival microcirculatory functions in inflamed gingiva of dogs
Authors: Tanaka M. , Hanioka T. , Kishimoto M. , Shizukuishi S.
Published: December 2005

Abstract. The effect of mechanical toothbrush stimulation on gingival microcirculatory functions was examined with and without removal of supragingival plaque in inflamed gingiva of 6 dogs. After removal of the ligatures, 4 treatment modalities: mechanical stimulation by vibration (MS), removal of supragingival plaque (PR), combination (MS + PR) and no treatment (NT), were administered to each quadrant for 2 weeks. Both quadrants with plaque removal showed a marked decrease in the gingival index score, while slight and moderate decreases were observed in NT and MS quadrants, respectively. Changes in gingival crevicular fluid flow, pocket oxygen tension and hemoglobin oxygen saturation in the gingival were significant in the MS, PR and MS + PR quadrants. Significant treatment‐by‐time effects were found for all of the parameters of microcirculatory function between NT and MS quadrants, and gingival crevicular fluid flow between PR and MS + PR quadrants, respectively. These findings suggest that mechanical stimulation with a toothbrush may offer an additional benefit to gingival microcirculatory functions in inflamed gingiva.
Effects of proximal vertical destructions on periodontal status and healing in adjacent proximal sites with horizontal destruction
Authors: Ehnevid Helge , Jansson Leif
Published: December 2005

Abstract. The purpose of the study was to investigate if the presence of vertical destruction in proximal sites influences periodontal status and healing in adjacent sites in the same proximal space without vertical destruction. The investigation was conducted as a retrospective study on a 3‐year consecutive referral population of periodontitis‐prone patients based on full‐mouth oral radiographic examinations, probing pocket depth registrations and plaque scores. The analyses were performed by using regression analyses on a final sample of 1169 (periodontal status) and 1051 (periodontal healing) proximal sites in 163 patients. The relative radiographic attachment level (RRAL) in proximal horizontal sites did not depend on the type of destruction, vertical or horizontal, in the adjacent proximal sites. However, after non‐surgical treatment, pocket‐depth reduction in proximal sites with horizontal destruction was significantly reduced in the presence of a vertical destruction in the adjacent proximal site compared to the corresponding sites adjacent to a horizontal defect. It was concluded that marginal periodontal healing in proximal sites with horizontal destruction is impaired by the presence of a vertical destruction in the adjacent proximal site.
Semi‐automated measurement of motility of human subgingival microflora by image analysis
Authors: Ojima M. , Tamagawa H. , Hayashi N. , Hanioka T. , Shizukuishi S.
Published: December 2005

Abstract. The purpose of this investigation was to quantitatively estimate bacterial motility by image analysis, and to apply this method for the measurement of motility of human subgingival microflora. We developed a semi‐automated method for the quantification of bacterial motility using video microscopy, digitization and image processing. Moving images of both authentic bacterial samples and clinical samples were recorded using a phase contrast microscope with a high speed (l/100 s) shutter camera. The motility was evaluated by measuring the total number of pixels remaining after the subtraction of 2 serial video images. The total number of pixels was significantly correlated with both the sum of the velocity of each bacterial cell and the number of motile bacteria on the same original images. Motility of subgingival microflora from 140 clinical samples tested was measured at 0 pixels to 3600 pixels, whereas the effect of Brownian movement was less than 150 pixels. The motility of subgingival microflora estimated with this image analysis system did not differ much from objective judgments by the naked eyes of experts. These results suggest that a semi‐automated image analysis system may be useful in the evaluation of the motility of human subgingival microflora.
A possible association of α1‐antitrypsin deficiency with the periodontal condition in adults
Authors: Fokkema Schelte J. , Timmerman Mark F. , van der Weijden Fridus A. , Wolffe Gordon N. , Renggli Heinz H.
Published: December 2005

Abstract. α1‐antitrypsin (α1AT) is a serum inhibitor of several neutrophil‐derived proteolytic enzymes, the serine proteinases. In certain individuals, a deficiency of this enzyme inhibitor is present, whereby only 10 to 20% of the normal concentration is present in the circulation. The purpose of this study was to evaluate the influence of this α1AT deficiency on the periodontal condition in a case control study 10 patients aged 20–50 years with a mean age of 32 and showing a deficiency of αlAT were randomly selected from a national data bank, which contains persons known to be affected with the αlAT deficiency state. Control subjects were matched for age, gender and socio‐economic status. Full periodontal charting on all subjects was performed on 6 sites per tooth, including probing attachment level, probing depth, bleeding on probing and a plaque score. Analysis of the data revealed no differences with regard to attachment loss between the two groups. The deficiency group showed 9.3% pockets ≥5 mm and the matched control group 5.9%. When these results were covariated with plaque scores, the deficiency group appeared to have a higher number of sites with probing depths ≥5 mm.
A controlled multicenter study of adjunctive use of tetracycline periodontal fibers in mandibular class II furcations with persistent bleeding
Authors: Tonetti M. S. , Cortellini P. , Carnevale G. , Cattabriga M. , de Sanctis M. , Prato G. P. Pini
Published: December 2005

Abstract. The aim of this randomized single‐blind multicenter controlled clinical trial was to clinically evaluate the effectiveness of adjunctive local controlled drug delivery in the control of bleeding on probing in mandibular class II furcations during maintenance care. 127 patients presenting with a class II mandibular furcation with bleeding on probing were included in the study. They had been previously treated for periodontitis and were participating in supportive care programs in periodontal speciality practices. Treatments consisted of scaling and root planing with oral hygiene instructions (control) and scaling and root planing and oral hygiene combined with local controlled drug delivery with tetracycline fibers (test). The following outcomes were evaluated at baseline and 3 and 6 months after therapy at the furcation site: bleeding on controlled force probing (BOP), probing pocket depth (PD) and clinical attachment levels (CAL). Levels of oral hygiene and smoking status were also assessed. Both test and controls resulted in significant improvements of BOP and PD at 3 and 6 months. The test treatment, however, resulted in significantly better improvements: BOP decreased by 52% in the control group and by 70% in the test group at 3 months; at 6 months, however, the difference was no longer significant. The test treatment resulted in a 0.5 mm greater reduction of PD than the control at 3 months, the improvement was highly significant but its duration did not extend until the 6 months evaluation. No differences were observed in terms of changes in CAL. These data indicate that addition of tetracycline fibers to mechanical therapy alone resulted in improved control of periodontal parameters during periodontal maintenance of class II mandibular furcations. Short duration of the effect, however, requires further investigations to optimize conservative treatment of these challenging defects.
Biochemical Microarrays for Studying Chemical Biology Interaction: DiscoveryDotTM Technology
Authors: Horiuchi Kurumi Y. , Wang Yuan , Ma Haiching
Published: December 2005

DiscoveryDotTM is a novel solution‐phase technology for chemical compound microarrays which has been validated for several targets (e.g. serine proteases, cysteine proteases, metalloproteinases, histone deacetylases, phosphatases and various kinases) of significance for drug discovery. The historical context of microarrays and the advantages of the DiscoveryDotTM technology are highlighted. The success of this chemical microarray technology will provide unprecedented possibility and capability for parallel functional analysis of hundreds of thousands of chemical compounds.
Expression and biophysical properties of Kv1 channels in supragranular neocortical pyramidal neurones
Authors: Guan D. , Lee J. C. F. , Tkatch T. , Surmeier D. J. , Armstrong W. E. , Foehring R. C.
Published: December 2005

Potassium channels are extremely diverse regulators of neuronal excitability. As part of an investigation into how this molecular diversity is utilized by neurones, we examined the expression and biophysical properties of native Kv1 channels in layer II/III pyramidal neurones from somatosensory and motor cortex. Single‐cell RT‐PCR, immunocytochemistry, and whole cell recordings with specific peptide toxins revealed that individual pyramidal cells express multiple Kv1 α‐subunits. The most abundant subunit mRNAs were Kv1.1 > 1.2 > 1.4 > 1.3. All of these subunits were localized to somatodendritic as well as axonal cell compartments. These data suggest variability in the subunit complexion of Kv1 channels in these cells. The α‐dendrotoxin (α‐DTX)‐sensitive current activated more rapidly and at more negative potentials than the α‐DTX‐insensitive current, was first observed at voltages near action potential threshold, and was relatively insensitive to holding potential. The α‐DTX‐sensitive current comprised about 10% of outward current at steady‐state, in response to steps from −70 mV. From −50 mV, this percentage increased to ∼20%. All cells expressed an α‐DTX‐sensitive current with slow inactivation kinetics. In some cells a transient component was also present. Deactivation kinetics were voltage dependent, such that deactivation was slow at potentials traversed by interspike intervals during repetitive firing. Because of its kinetics and voltage dependence, the α‐DTX‐sensitive current should be most important at physiological resting potentials and in response to brief stimuli. Kv1 channels should also be important at voltages near threshold and corresponding to interspike intervals.
Differential polyamine sensitivity in inwardly rectifying Kir2 potassium channels
Authors: Panama Brian K. , Lopatin Anatoli N.
Published: December 2005

Recent studies have shown that Kir2 channels display differential sensitivity to intracellular polyamines, and have raised a number of questions about several properties of inward rectification important to the understanding of their physiological roles. In this study, we have carried out a detailed characterization of steady‐state and kinetic properties of block of Kir2.1–3 channels by spermine. High‐resolution recordings from outside‐out patches showed that in all Kir2 channels current–voltage relationships display a ‘crossover’ effect upon change in extracellular K+. Experiments at different concentrations of spermine allowed for the characterization of two distinct shallow components of rectification, with the voltages for half‐block negative (V11/2) and positive (V21/2) to the voltage of half‐block for the major steep component of rectification (V01/2). While V11/2 and V21/2 voltages differ significantly between Kir2 channels, they were coupled to each other according to the equation V11/2−V21/2= constant, strongly suggesting that similar structures may underlie both components. In Kir2.3 channels, the V21/2 was ∼50 mV positive to V01/2, leading to a pattern of outward currents distinct from that of Kir2.1 and Kir2.2 channels. The effective valency of spermine block (Z0) was highest in Kir2.2 channels while the valencies in Kir2.1 and Kir2.3 channels were not significantly different. The voltage dependence of spermine unblock was similar in all Kir2 channels, but the rates of unblock were ∼7‐fold and ∼16‐fold slower in Kir2.3 channels than those in Kir2.1 and Kir2.2 when measured at high and physiological extracellular K+, respectively. In all Kir2 channels, the instantaneous phase of activation was present. The instantaneous phase was difficult to resolve at high extracellular K+ but it became evident and accounted for nearly 30–50% of the total current when recorded at physiological extracellular K+. In conclusion, the data are consistent with the universal mechanism of rectification in Kir2 channels, but also point to significant, and physiologically important, quantitative differences between Kir2 isoforms.
Topographic organization in the auditory brainstem of juvenile mice is disrupted in congenital deafness
Authors: Leao Richardson N. , Sun Hong , Svahn Katarina , Berntson Amy , Youssoufian Monique , Paolini Antonio G. , Fyffe Robert E. W. , Walmsley Bruce
Published: December 2005

There is an orderly topographic arrangement of neurones within auditory brainstem nuclei based on sound frequency. Previous immunolabelling studies in the medial nucleus of the trapezoid body (MNTB) have suggested that there may be gradients of voltage‐gated currents underlying this tonotopic arrangement. Here, our electrophysiological and immunolabelling results demonstrate that underlying the tonotopic organization of the MNTB is a combination of medio‐lateral gradients of low‐and high‐threshold potassium currents and hyperpolarization‐activated cation currents. Our results also show that the intrinsic membrane properties of MNTB neurones produce a topographic gradient of time delays, which may be relevant to sound localization, following previous demonstrations of the importance of the timing of inhibitory input from the MNTB to the medial superior olive (MSO). Most importantly, we demonstrate that, in the MNTB of congenitally deaf mice, which exhibit no spontaneous auditory nerve activity, the normal tonotopic gradients of neuronal properties are absent. Our results suggest an underlying mechanism for the observed topographic gradient of neuronal firing properties in the MNTB, show that an intrinsic neuronal mechanism is responsible for generating a topographic gradient of time‐delays, and provide direct evidence that these gradients rely on spontaneous auditory nerve activity during development.
Effect of inspiratory muscle work on peripheral fatigue of locomotor muscles in healthy humans
Authors: Romer Lee M. , Lovering Andrew T. , Haverkamp Hans C. , Pegelow David F. , Dempsey Jerome A.
Published: December 2005

The work of breathing required during maximal exercise compromises blood flow to limb locomotor muscles and reduces exercise performance. We asked if force output of the inspiratory muscles affected exercise‐induced peripheral fatigue of locomotor muscles. Eight male cyclists exercised at ≥ 90% peak O2 uptake to exhaustion (CTRL). On a separate occasion, subjects exercised for the same duration and power output as CTRL (13.2 ± 0.9 min, 292 W), but force output of the inspiratory muscles was reduced (−56%versus CTRL) using a proportional assist ventilator (PAV). Subjects also exercised to exhaustion (7.9 ± 0.6 min, 292 W) while force output of the inspiratory muscles was increased (+80%versus CTRL) via inspiratory resistive loads (IRLs), and again for the same duration and power output with breathing unimpeded (IRL‐CTRL). Quadriceps twitch force (Qtw), in response to supramaximal paired magnetic stimuli of the femoral nerve (1–100 Hz), was assessed pre‐ and at 2.5 through to 70 min postexercise. Immediately after CTRL exercise, Qtw was reduced −28 ± 5% below pre‐exercise baseline and this reduction was attenuated following PAV exercise (−20 ± 5%; P < 0.05). Conversely, increasing the force output of the inspiratory muscles (IRL) exacerbated exercise‐induced quadriceps muscle fatigue (Qtw=−12 ± 8% IRL‐CTRL versus−20 ± 7% IRL; P < 0.05). Repeat studies between days showed that the effects of exercise per se, and of superimposed inspiratory muscle loading on quadriceps fatigue were highly reproducible. In conclusion, peripheral fatigue of locomotor muscles resulting from high‐intensity sustained exercise is, in part, due to the accompanying high levels of respiratory muscle work.
Parallelism in Planar Manipulators: A Measure
Authors: Rao A. C.
Published: December 2005

Parallelism can be associated with every closed kinematic chain or its representative graph. Parallelism throws light on work space, rigidity, speed ratios (mechanical advantage), etc., and is of great help in selecting multi degree-of-freedom (dof) chains for robotic applications. Numerous distinct chains with the same number of links and dof exist. The extent of parallelism differs from chain to chain and hence a numerical measure is necessary to quantify the same so that the designer gains insight simply based on the structure without having to actually design all the distinct chains before selecting the best chain for the specified task. To the author’s knowledge, no measure is available in graph theory to quantify the extent of parallelism and the present work is an attempt in this direction.
Multistage Aspects and Unsteady Effects of Stator and Rotor Clocking in an Axial Turbine With Low Aspect Ratio Blading
Authors: Behr T. , Porreca L. , Mokulys T. , Kalfas A. I. , Abhari R. S.
Published: December 2005

This paper presents the outcome of a recent study in clocking-related flow features and multistage effects occurring in high-pressure turbine blade geometries. The current investigation deals with an experimentally based systematic analysis of the effects of both stator-stator and rotor-rotor clocking. Due to the low aspect ratio of the turbine geometry, the flow field is strongly three-dimensional and is dominated by secondary flow structures. The investigation aims to identify the flow interactions involved and the associated effects on performance improvement or degradation. Consequently a three-dimensional numerical analysis has been undertaken to provide the numerical background to the test case considered. The experimental studies were performed in a two-stage axial research turbine facility. The turbine provides a realistic multi-stage environment, in which both stator blade rows and the two rotors can be clocked relative to each other. All blade rows have the same blade number count, which tends to amplify clocking effects. Unsteady and steady measurements were obtained in the second stage using fast response aerodynamic probes and miniature pneumatic five-hole probes. The current comprehensive investigation has shown that multistage and unsteady flow effects of stator and rotor clocking in low aspect ratio turbines are combined in a nonlinear fashion caused by axial and radial redistribution of low energy fluid. The integral result of clocking on stage efficiency is compensated by competing loss generating mechanisms across the span.