bluuebunny/crossref_metadata_2025 huggingface dataset:
Simplified Methods of Implant Treatment in the Edentulous Lower Jaw: A 3‐Year Follow‐Up Report of a Controlled Prospective Study of One‐Stage versus Two‐Stage Surgery and Early Loading
Authors: Engquist Bo , Åstrand Per , Anzén Bengt , Dahlgren Simon , Engquist Eva , Feldmann Hartmut , Karlsson Ulf , Nord Per‐Gunnar , Sahlholm Sten , Svärdström Pia
Published: August 2006

Background:

Interest in the use of one‐stage surgery and immediate loading of oral implants has lately been increasing.

Purpose:

The aim of this study was to compare the 3‐year results of one‐stage surgery versus two‐stage surgery, early loading versus loading after a 3‐month healing period, and the use of one‐piece implants versus the use of two‐piece implants.

Materials and Methods:

The study included 108 patients with edentulous mandibles. Each patient was treated with four Brånemark System® implants (Nobel Biocare AB, Göteborg, Sweden) and with full fixed prostheses. Patients were consecutively treated and were distributed in four groups: group A (one‐stage surgery), group B (control group with two‐stage surgery), group C (one‐piece implants), and group D (early loading). In groups A and B Brånemark Standard implants and standard abutments were used. In group C the conical one‐piece Brånemark implant was used, and in group D the patients had Brånemark System Mk III implants together with multiunit abutments. All patients were observed for 3 years.

Results:

Of the 432 inserted implants, 24 were lost. Survival rates in the three experimental groups ranged from 93.2 to 93.3% whereas the survival rate in group B (the control group with two‐stage surgery) was 97.5%. The differences between the groups were not statistically significant. The changes in marginal bone level were measured from fixture insertion to the final follow‐up at 3 years. The bone loss in group D (early loading) was significantly less than in group B (the control group) whereas there were no differences in marginal bone change between the other groups.

Conclusions:

Early loading seemed to give good results in the anterior part of the mandible. The survival rate of the early‐loaded implants did not significantly differ from that of implants inserted with the conventional two‐stage procedure, but the mean marginal bone loss around the surviving implants was less with early loading.
An Antibacterial Surface on Dental Implants, Based on the Photocatalytic Bactericidal Effect
Authors: Suketa Naoki , Sawase Takashi , Kitaura Hideki , Naito Mariko , Baba Koumei , Nakayama Koji , Wennerberg Ann , Atsuta Mitsuru
Published: August 2006

Background:

It is well known that the moderately roughened surfaces of dental implants enhance direct bone‐implant contact. However, rough implant surfaces, as compared to smooth surfaces, are thought to pose a higher risk of bacterial infection when exposed to the oral cavity.

Purpose:

This study was focused on evaluating the photocatalytic bactericidal effects of anatase titanium dioxide (TiO2) on gram‐negative anaerobic bacteria known to be associated with perümplantitis.

Materials and Methods:

A film of photocatalytic anatase TiO2 was added onto the surface of commercially pure titanium disks by plasma source ion implantation (PSII) followed by annealing. The photocatalytic properties of the film were confirmed by the degradation of methylene blue. Actinobacillus actinomycetemcomitans and Fusobacterium nucleatum cells were incubated anaerobically and seeded on the disk. The disks were then exposed to ultraviolet A (UVA) illumination from black light in an anaerobic environment. After illumination, the number of viable cells was counted in terms of colony‐forming units.

Results:

The anatase TiO2 film added by the PSII method and annealing exhibited a strong photocatalytic reaction under UVA illumination. The viability of both types of bacteria on the photocatalytic TiO2 film was suppressed to less than 1% under UVA illumination within 120 minutes.

Conclusion:

The bactericidal effect of the TiO2 photocatalyst is of great use for sterilizing the contaminated surface of dental implants.
Tissue Engineering with Recombinant Human Bone Morphogenetic Protein‐2 for Alveolar Augmentation and Oral Implant Osseointegration: Experimental Observations and Clinical Perspectives*
Authors: Wikesjö Ulf M. E. , Polimeni Giuseppe , Qahash Mohammed
Published: August 2006

Surgical placement of oral implants is governed by the prosthetic design and by the morphology and quality of the alveolar bone. Nevertheless implant placement often appears difficult, if at all possible, due to aberrations of the alveolar ridge. Hence prosthetically dictated implant positioning often entails augmentation of the alveolar ridge and adjoining structures. In this review we discuss recent observations of the biologic potential, clinical relevance, and perspectives of application of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) technologies for alveolar bone augmentation and oral implant osseointegration. Using discriminating critical‐size supraalveolar defects and clinical modeling in dogs, we show that rhBMP‐2 has a substantial potential for augmenting alveolar bone and supporting osseointegration of titanium oral implants. Moreover, using clinical modeling, we demonstrate re‐osseointegration in advanced periimplantitis defects and long‐term functional loading of titanium oral implants placed into rhBMP‐2‐induced bone. Our studies suggest that inclusion of rhBMP‐2 for alveolar bone augmentation and oral implant fixation will not only enhance the predictability of existing clinical protocol but also allow new approaches to these procedures.
Simplified Treatment of the Atrophic Posterior Maxilla via Immediate/Early Function and Tilted Implants: A Prospective 1‐Year Clinical Study
Authors: Calandriello Roberto , Tomatis Massimiliano
Published: August 2006

Background:

Posterior maxillae are often difficult to treat owing to the sinus antrum. Placing implants in remaining bone regions in the atrophic maxilla, without performing sinus grafting, is a challenge. Immediate function adds to this challenge.

Purpose:

The purpose of this study was to suggest and evaluate a simplified treatment concept for the rehabilitation of the atrophic maxilla using tilted implants subjected to immediate/early function.

Materials and Methods:

Eighteen patients were included in the study. Sixty implants were placed to support 19 fixed partial or full‐arch prostheses. Immediate/early function was applied. The patients were followed for a minimum of 1 year after prosthesis connection. Stability measurements and radiographic evaluation of the change of the marginal bone level were performed.

Results:

One axial and one tilted implant failed in one patient, giving a cumulative survival rate of 96.7%. No failure of provisional prostheses occurred. The mean marginal bone resorption recorded after 1 year was low (0.82 mm for axial implants and 0.34 mm for tilted implants).

Conclusion:

The results of the present study suggest that tilted implants placed in immediate function may be a viable treatment approach for the rehabilitation of the atrophied maxilla. Simplified treatment procedures, reduced surgical invasion, shorter treatment time, and reduced costs constitute some of the benefits for the patient and the clinician.
The Human Bone–Oxidized Titanium Implant Interface: A Light Microscopic, Scanning Electron Microscopic, Back‐Scatter Scanning Electron Microscopic, and Energy‐Dispersive X‐Ray Study of Clinically Retrieved Dental Implants
Authors: Schüpbach Peter , Glauser Roland , Rocci Antonio , Martignoni Massimiliano , Sennerby Lars , Lundgren AnnaKarin , Gottlow Jan
Published: August 2006

Background:

Surface modification of titanium implants by anodic oxidation may lead to enhanced bone integration. For instance, in vivo studies have demonstrated formation of more bone contacts in less time than for turned control implants. In addition, oxidized implants have shown a higher resistance to torque forces, indicating a strong interlock between bone and the oxide layer. However, the structure of the oxidized titanium‐bone interface in high resolution is not known.

Purpose:

The aim of the study was to analyze the human bone‐oxidized titanium interface at a high‐resolution level. Of particular interest was the relationship between bone tissue and the pores of the surface oxide.

Materials and Methods:

Twelve clinically retrieved implants with an oxidized surface (TiUnite™, Nobel Biocare AB, Göteborg, Sweden) were used. Seven were regular dental implants and five were experimental mini‐implants and had been subjected to immediate, early, or no loading. They were retrieved after 5 to 9 months of healing and were processed and analyzed using light microscopy, scanning electron microscopy (SEM) in normal and back‐scatter (BS‐SEM) modes, and energy‐dispersive x‐ray (EDX) analysis techniques.

Results:

Bone formation was observed to occur from adjacent bone structures toward the implant surface, and it was evident that bone formation had occurred at the implant surface. SEM, BS‐SEM, and EDX revealed that mineralized bone had grown into the pores of the surface oxide layer, including pores with small diameters (< 2 μm).

Conclusions:

The clinically retrieved oxidized implants showed evidence of bone growth into the pores of the surface oxide layer. The findings indicate the establishment of a strong interlock between the bone and the oxidized titanium implant, which is suggested to be beneficial for clinical performance.
Periimplant Soft Tissue Barrier at Experimental One‐Piece Mini‐implants with Different Surface Topography in Humans: A Light‐Microscopic Overview and Histometric Analysis
Authors: Glauser Roland , Schüpbach Peter , Gottlow Jan , Hämmerle Christoph H. F.
Published: August 2006

Background:

Following connection to the oral cavity, osseointegrated dental implants and surrounding tissues are exposed to microbiologic and biomechanical challenges. The establishment of a firm functional periimplant soft tissue barrier (PSTB) is considered to be important to protect the implant's interface from invasion of bacteria. The current knowledge on the histologic architecture of the PSTB is mainly based on animal experiments.

Purpose:

The aim of this study was to histologically characterize the PSTB formed in humans around experimental one‐piece mini‐implants with different surface topography.

Materials and Methods:

Five patients received a total of 12 experimental titanium, one‐piece mini‐implants with an oxidized (n = 4), an acid‐etched (n = 4), or a machined (n = 4) surface distal to therapeutic implants. Following transmucosal healing of 8 weeks and at abutment connection of the regular implants, the mini‐implants were harvested with a layer of surrounding hard and soft tissue. The specimens were fixed and processed for histologic sectioning according to standard procedures. The most central bucco‐oral section cut in the long axis was used for morphologic analyses of the PSTB. The vertical soft tissue morphology was quantified using histometric measurements.

Results:

The overall height of the soft tissue, that is, the biologic width, was around 4 to 4.5 mm and consisted of an epithelial and a supracrestal connective tissue barrier. The junctional epithelium established the attachment to the implant surface, whereas the collagen fibers and fibroblasts of the connective tissue seal were oriented parallel to the implant. The epithelial attachment was shorter at the oxidized and acid‐etched surfaces compared with the machined surfaces. Accordingly, the oxidized and acid‐etched mini‐implants exhibited a longer zone of connective tissue seal.

Conclusion:

The periimplant soft tissue formed at the experimental one‐piece mini‐implants in humans was of a character similar to that described in animal studies. The oxidized and acid‐etched implants revealed less epithelial downgrowth and longer connective tissue seal than machined implants.
Stimulation of Directed Bone Growth at Oxidized Titanium Implants by Macroscopic Grooves: An In Vivo Study
Authors: Hall Jan , Miranda‐Burgos Patricia , Sennerby Lars
Published: August 2006

Background:

The influence of thread design at the millimeter level and surface topography at the micrometer level on bone integration and the stability of dental implants have been studied extensively. However, less is known about the influence of implant structures in the range of 50 to 200 μm.

Purpose:

The present in vivo investigation was undertaken to study if bone formation and implant stability were influenced by 110 (S1) and 200 (S3) μm‐wide and 70 μm‐deep grooves positioned at a thread flank of oxidized titanium implants.

Materials and Methods:

Eighteen rabbits and oxidized titanium implants (3.75 mm in diameter and 7 mm long) were used in the study. Nine rabbits received three control implants and three test implants with a 110 μm‐wide groove added to one thread flank. The remaining nine rabbits received three control implants and three test implants with a 200 μm‐wide groove. The animals were followed for 6 weeks. Removal torque (RTQ) tests were applied to two of the implants in each leg. The remaining implant per leg was retrieved for histology. The degree of bone fill within the grooves and corresponding bone formation at the opposing surfaces, the bone area within the threads, and the degree of bone‐implant contact were calculated for each implant.

Results:

The histologic analyses revealed an affinity for bone formation within the grooves. The RTQ tests showed that the peak RTQ was approximately 30% higher for the S1 implants compared with control implants without a groove. The difference was statistically significant (p < .05) for tibial and pooled implants. A similar but smaller and not statistically significant effect, approximately 8%, was measured for the S3 implants. The histomorphometric measurements confirmed the observed affinity of bone for the grooves. For S1 implants, 78.7 ± 15.8% of the grooves were filled with bone, whereas only 46.2 ± 27% of the corresponding flank surface showed the presence of bone (p < .05). The corresponding figures for S3 and control implants were 72.7 ± 25.1% and 48.5 ± 13.6%, respectively (p < .05). The degrees of bone‐implant contact and bone area within the threads were similar for test and control implants.

Conclusion:

It is concluded that 110 and 200 μm‐wide and 70 μm‐deep grooves at oxidized implant surfaces stimulated bone to preferentially form within and along the groove in the rabbit model. The 110 μm‐wide groove was shown to increase the resistance to shear forces significantly. It is suggested that implants with such a groove may be one way to optimize implant stability in suboptimal clinical conditions.
Immediate/Early Function of Brånemark System® TiUnite™ Implants in Fresh Extraction Sockets in Maxillae and Posterior Mandibles: An 18‐Month Prospective Clinical Study
Authors: Vanden Bogaerde Leonardo , Rangert Bo , Wendelhag Inger
Published: August 2006

Background:

The advantages of placing implants in fresh extraction sockets and putting them in immediate/early function are many. A predicable protocol opens the possibility of performing a single surgical procedure, giving the patient a temporary prosthesis immediately, and minimizing the shrinkage of hard tissue and soft tissue recession.

Purpose:

The aim of the present study was to develop a strict protocol for and to evaluate the feasibility of immediate/early function on implants placed in fresh extraction sockets located in maxillae and posterior mandibles, including defects around the implants treated according to a regenerative procedure.

Materials and Methods:

Nineteen patients were treated after tooth extraction according to an immediate function protocol and were observed for 18 months. Fifty Mk IV TiUnite™ (Nobel Biocare AB, Göteborg, Sweden) implants were installed in partially edentulous areas in maxillae (n = 17) and posterior mandibles (n = 5). Implants were installed directly into the alveoli, and the temporary prostheses were connected immediately after surgery (n= 11) or within 7 days, that is, an “early function” procedure (n = 11). Thirteen implants did not require any type of regenerative procedure, whereas the remaining 37 implants had filling with autogenous bone, 4 of which also had a resorbable membrane. Standardized intraoral radiographs were taken for evaluation of marginal bone level, and 38 of the implants were systematically checked by resonance frequency analysis.

Results:

All patients were followed for 18 months, and none of the 50 implants failed. However, one implant showed signs of failure after 6 weeks, but once the occlusal load was removed, the implant regained its stability completely, no longer demonstrated symptoms, and could be used successfully for prosthetic rehabilitation. The mean value of the implant stability quotient was 60 at baseline (range 45–75) and 63 after 6 months (range 46–75). The marginal bone resorption was 0.9 mm (SD 1.1 mm; n = 48) 18 months after implant insertion (1 year after final prosthesis).

Conclusion:

The immediate placement of implants into fresh extraction sockets combined with immediate/early function procedures seems to be a safe and reliable procedure when using a strict protocol.
Symmetry of non‐carious cervical lesions in canines and premolars
Authors: Maseki Toshio , Tanaka Hisayoshi
Published: August 2006

Objectives:  Clinically non‐carious cervical lesions (NCCLs) are frequently seen. The aim of this study was to investigate the relationship between the shape and symmetry of NCCLs, wear of cuSPS and triangular ridge, and the curvature of the tooth root.

Methods:  One hundred and twenty‐nine extracted human upper canine teeth and 274 extracted human upper premolar teeth with NCCLs were used in this study. The specimens were studied using photographs and three‐dimensional scanning.

Results:  Asymmetric NCCL was observed in 69.0% of the canines and 44.5% of the premolars. Wear of cusp and lingual ridges was observed in 82.9% and 93.0% of the canines, respectively. Wear of the buccal cusp and buccal triangular ridge was observed in 85.4% and 89.8% of the premolars, respectively. On the other hand, the wear of lingual cusp and lingual triangular ridge was observed in 89.1% and 93.8% of the premolars, respectively. The curvature of the root was observed in 48.1% of the canines and 43.4% of the premolars.

Conclusions:  There was no relationship between the symmetry of NCCLs, and the wear of cuSPS and triangular ridges for either canines or premolars. Although there was a relationship (p < 0.05) between the symmetry of NCCL and the curvature of the root in the canines, no relationship was observed between the symmetry of NCCL and the curvature of the root in the premolars.
The effect of age on the function of the masticatory system – an electromyographical analysis
Authors: Galo Rodrigo , Vitti Mathias , Santos Carla Moreto , Hallak Jaime Eduardo Cecílio , Regalo Simone Cecílio Hallak
Published: August 2006

Background:  Old age is the last stage of human life and, unfortunately, the ageing rhythm of the oral cavity and masticatory system seems to be rather accelerated. Hence, there is a reduction in the amount of food ingested, establishing the imbalance of nutritional phenomena.

Objective:  To assure a better quality of life for the elderly, it is necessary to understand their masticatory system.

Materials and methods:  An electromyographical analysis of the masticatory system in 10 individuals aged between 60–75 years (group 1) and 10 between 23–30 years old (group 2) was carried out. The analysis was performed using a MyoSystem‐Br1 electromyographer with differential active electrodes. The test was registered during positioning and functional conditions, such as chewing, and the muscles assessed were the temporalis and masseter. Data were normalised by maximum voluntary contraction (MVC), and the results were analysed statistically using independent t‐test during the comparison between groups.

Results:  Statistical significance (p ≤ 0.05) was found in the analysis of various activities, in which the elderly showed greater electromyographical activity values relative to their MVC during the different mandibular positions, such as left laterality. While the elderly subjects revealed values of 30% relative to their MVC, the young revealed 10%. However, during masticatory activities, the elderly revealed values of up to 79%, and the young of 108%, relative to their MVC, such as when they are chewing peanuts.

Conclusion:  It could be concluded that the elderly show hyperactivity of masticatory musculature during posture maintenance and a slight hypoactivity of this musculature during chewing when analysed side by side with young individuals.
Effects of Perinatal Combined Exposure to 1,1‐Dichloro‐2,2 bis (p‐chlorophenyl) ethylene and Tributyltin on Male Reproductive System
Authors: Makita Yuji , Omura Minoru
Published: August 2006

Abstract: Prenatal or early postnatal exposure to some synthetic chemicals may affect the later reproductive system of the offspring. There may also be unique responses observed due to exposure to combinations of chemicals that are not observed when the chemicals are present individually. 1,1‐Dichloro‐2,2 bis (p‐chlorophenyl) ethylene (p,p′‐DDE) is a persistent metabolite of DDT and tributyltin (TBT) compounds are used primarily as antifouling agents, as they exert biocidal actions. p,p′‐DDE and TBT are ubiquitously distributed in the environment. Oral p,p′‐DDE and TBT intake through marine products is demonstrated to be high in Japan. Consequently, the foetus and neonate are supposed to be exposed much more to p,p′‐DDE and TBT via the maternal body. Therefore, effects of perinatal exposure to p,p′‐DDE and/or TBT on the reproductive system after maturation have been investigated in rat male offspring of dams orally administered 125 ppm p,p′‐DDE (approximately 10 mg/kg) and 25 ppm TBT (approximately 2 mg/kg) during the gestational and lactational period. In this study, growth retardation attributed to TBT has sustained in rat male offspring after perinatal exposure. However, perinatal exposure to p,p′‐DDE and TBT failed to affect the male reproductive organs and sperm parameters in matured male offspring.
Normalized lengthening peak torque is associated with temporal twitch characteristics in elderly women but not young women
Authors: Cannon J. , Kay D. , Tarpenning K. M. , Marino F. E.
Published: August 2006

Aim:  To determine if greater normalized torque during maximal effort lengthening actions in elderly women compared with young women is related to age‐associated adjustments in neural activation and/or contractile function.

Methods:  The right knee extensors of 14 young women (21–30 years) and 12 elderly women (65–78 years) were assessed for isometric, shortening and lengthening peak torque, electromyography (EMG) activity, and isometric twitch contractile properties. Knee extensor contractile tissue volume was determined using magnetic resonance imaging. Normalized torque was determined as peak torque per unit of knee extensor contractile tissue volume.

Results:  Normalized torque during the isometric and shortening actions was similar between age groups (P > 0.05); however, lengthening normalized torque was significantly higher for the elderly women (P < 0.05). In the young women, a significant relationship existed between normalized torque and EMG for all muscle actions (P < 0.05), while no association was found between normalized torque and temporal twitch characteristics for any muscle action (P > 0.05). In the elderly women, a significant relationship existed between normalized torque and EMG for the isometric and shortening muscle actions (P < 0.05), but not for lengthening normalized torque and EMG (P > 0.05). Furthermore, no association existed between isometric and shortening normalized torque, and temporal twitch characteristics in the elderly women (P > 0.05); however, a significant relationship existed between lengthening normalized torque, and the rate of relaxation and contraction duration (P < 0.05).

Conclusions:  The greater capacity to develop lengthening peak torque relative to contractile tissue volume in the elderly women appeared to be associated with age‐related adjustments in the temporal twitch characteristics rather than neural activation.
Chest wall kinematics, respiratory muscle action and dyspnoea during arm vs. leg exercise in humans
Authors: Romagnoli I. , Gorini M. , Gigliotti F. , Bianchi R. , Lanini B. , Grazzini M. , Stendardi L. , Scano G.
Published: August 2006

Aim:  We hypothesize that different patterns of chest wall (CW) kinematics and respiratory muscle coordination contribute to sensation of dyspnoea during unsupported arm exercise (UAE) and leg exercise (LE).

Methods:  In six volunteer healthy subjects, we evaluated the volumes of chest wall (Vcw) and its compartments, the pulmonary apposed rib cage (Vrc,p), the diaphragm‐abdomen apposed rib cage (Vrc,a) and the abdomen (Vab), by optoelectronic plethysmography. Oesophageal, gastric and trans‐diaphragmatic pressures were simultaneously measured. Chest wall relaxation line allowed the measure of peak rib cage inspiratory muscle, expiratory muscle and abdominal muscle pressures. The loop Vrc,p/Vrc,a allowed the calculation of rib cage distortion. Dyspnoea was assessed by a modified Borg scale.

Results:  There were some differences and similarities between UAE and LE. Unlike LE with UAE: (i) Vcw and Vrc,p at end inspiration did not increase, whereas a decrease in Vrc,p contributed to decreasing CW end expiratory volume; (ii) pressure production of inspiratory rib cage muscles did not significantly increase from quiet breathing. Not unlike LE, the diaphragm limited its inspiratory contribution to ventilation with UAE with no consistent difference in rib cage distortion between UAE and LE. Finally, changes in abdominal muscle pressure, and inspiratory rib cage muscle pressure predicted 62% and 41.4% of the variability in Borg score with UAE and LE, respectively (P < 0.01).

Conclusion:  Leg exercise and UAE are associated with different patterns of CW kinematics, respiratory muscle coordination, and production of dyspnoea.
Risk perception among older South Asian people in the UK with type 2 diabetes
Authors: Macaden Leah , Clarke Charlotte L.
Published: August 2006

Aim.  To report on a study which developed a knowledge of the experiences of South Asian people with diabetes in the UK in relation to socio‐cultural and dietary practices, religion and ageing influences on the perception and understanding of risks.

Background.  South Asian people have enhanced vulnerability to poor health as a result of diabetes. Risk perception and management is culturally mediated, yet imperative to the behaviour adjustments required for diabetes management.

Method.  A grounded theory study with data collected by focus group with ethnic health development workers and individual interviews with 20 older people with diabetes. Where necessary, interpreters were involved in data collection.

Findings.  A number of issues influence the perception of risk among South Asian older people with diabetes: beliefs about its cause, perceived severity and its visibility, food and its social function, religion and beliefs about external control over their life span and diabetes management. People weighed up the risks in making decisions about issues such as dietary management and the emphasis placed on diabetes as a pathology.

Conclusion.  Good risk communication will maintain the current trend of improving patient's choice and self‐management in health care, and there is a need for this to be sensitive to the particular issues faced by South Asians with diabetes in the UK.
Restraint removal: tension between protective custody and human rights
Authors: Koch Susan , Nay Rhonda , Wilson Jacinda
Published: August 2006

Aims and objectives.  To describe the culture of an aged care facility relating to restraint use and provide insight into the process of changing to minimal restraint care.

Background.  In 1999, the accreditation process for residential aged care facilities (This term has been used in Australia since around 1997 and replaces the terms ‘nursing homes’ and ‘hostels’) in Australia was extended to include a review of restraint use, with the view to minimization. As using restraint had traditionally been viewed as acceptable, it was expected that there would be tensions involved for staff making the transition to providing minimal restraint care.

Design.  The research was situated within the qualitative paradigm and guided by symbolic interactionism, grounded theory, and case study.

Methods.  Data were collected through observation of instances of restraint, individual interviews with staff, and document analysis.

Results.  The transition to minimal restraint care was associated with tensions for staff. Whilst efforts had been made to make the facility restraint‐free, bedrails were still in evidence, and were not necessarily viewed by staff as constituting restraint.

Conclusions.  Nurses may experience a tension between human rights and duty of care when adopting restraint‐minimization practices.

Relevance to clinical practice.  Tensions may be alleviated by adopting a universal definition of restraint, acquiring physical resources and new skills in care delivery and modifying staff, resident and family attitudes towards the delivery of care.
A Comparative Study of Supported TiO2 as Photocatalyst in Water Decontamination at Solar Pilot Plant Scale
Authors: Kus Mahmut , Gernjak Wolfgang , Ibáñez Pilar Fernández , Rodríguez Sixto Malato , Gálvez Julián Blanco , Icli Siddik
Published: August 2006

The degradation of gallic acid and imidacloprid with supported Millennium PC500 and Degussa P25 TiO2 is reported. TiO2 particles were immobilized using a titanium sol-solution and direct deposition on glass supports. The film characterization was done by x-ray diffraction, scanning electron microscopy, and atomic force microscopy, and degradation of organic compounds was monitored by high-performance liquid chromatography, total organic carbon analyzer, and ion chromatography. The experiments were performed under sunlight in compound parabolic collector plants with flat supports inside the glass tubes. Photocatalytic activity of the films was compared and identified. Although sol-gel coatings had better mechanical properties, mineralization was observed to be approximately five times slower than paste-deposited films. Photoactivity of the films decreased with silver deposition due to the nature of the organic compounds. The rate constants were calculated to be between 2×10−1 and 6×10−2mgm2∕kJ for organic compounds, and 6×10−2 and 6×10−3 for total organic carbon.
CVT Rolling Traction Drives—A Review of Research Into Their Design, Functionality, and Modeling
Authors: Akehurst S. , Parker D. A. , Schaaf S.
Published: August 2006

In this paper we detail a review of the current state of published work regarding the modeling of rolling traction drive Continuously Variable Transmissions (CVTs). An overview of CVTs operating by traction through small contact areas is performed, the layouts and kinematics of leading examples are reviewed, including the factors affecting design optimization. Properties of the traction contacts are considered in detail, with particular attention to elastohydrodynamic lubrication and asperity contact. Factors affecting the traction coefficient are reviewed and fundamental empirical predictions are contrasted with modern modeling computations. Finally measurements of the rheology of traction fluids are considered, leading to a definition of ideal properties and the development of proprietary fluids.
Product Design Selection With Preference and Attribute Variability for an Implicit Value Function
Authors: Maddulapalli A. K. , Azarm S.
Published: August 2006

An important aspect of engineering product design selection is the inevitable presence of variability in the selection process. There are mainly two types of variability: variability in the preferences of the decision maker (DM) and variability in attribute levels of the design alternatives. We address both kinds of variability in this paper. We first present a method for selection with preference variability alone. Our method is interactive and iterative and assumes only that the preferences of the DM reflect an implicit value function that is differentiable, quasi-concave and non-decreasing with respect to attributes. The DM states his/her preferences with a range (due to the variability) for marginal rate of substitution (MRS) between attributes at a series of trial designs. The method uses the range of MRS preferences to eliminate “dominated designs” and then to find a set of “potentially optimal designs.” We present a payload design selection example to demonstrate and verify our method. Finally, we extend our method for selection with preference variability to the case where the attribute levels of design alternatives also have variability. We assume that the variability in attribute levels can be quantified with a range of attribute levels.
Topology and Dimensional Synthesis of Compliant Mechanisms Using Discrete Optimization
Authors: Lu Kerr-Jia , Kota Sridhar
Published: August 2006

A unified approach to topology and dimensional synthesis of compliant mechanisms is presented in this paper as a discrete optimization problem employing both discrete (topology) and continuous (size) variables. The synthesis scheme features a design parameterization method that treats load paths as discrete design variables to represent various topologies, thereby ensuring structural connectivity among the input, output, and ground supports. The load path synthesis approach overcomes certain design issues, such as “gray areas” and disconnected structures, inherent in previous design schemes. Additionally, multiple gradations of structural resolution and a variety of configurations can be generated without increasing the number of design variables. By treating topology synthesis as a discrete optimization problem, the synthesis approach is incorporated in a genetic algorithm to search for feasible topologies for single-input single-output compliant mechanisms. Two design examples, commonly seen in the compliant mechanisms literature, are included to illustrate the synthesis procedure and to benchmark the performance. The results show that the load path synthesis approach can effectively generate well-connected compliant mechanism designs that are free of gray areas.
Design of a Passive Gravity-Balanced Assistive Device for Sit-to-Stand Tasks
Authors: Fattah Abbas , Agrawal Sunil K. , Catlin Glenn , Hamnett John
Published: August 2006

A sit-to-stand assist device can serve the needs of people suffering from muscle weakness due to age or disabilities that make sit-to-stand a difficult functional task. The objective of this paper is to design a passive gravity-balancing assist device for sit-to-stand motion. In our study, it has been shown that the contribution to the joint torques by the gravitational torque is dominant during sit-to-stand motion. On the basis of this result, a gravity balanced assistive device is proposed. This passive device uses a hybrid method to identify the center-of-mass of the system using auxiliary parallelograms first. Next, appropriate springs are connected to the device to make the total potential energy of the system due to the gravity and the springs constant during standing up. A demonstration prototype with the underlying principles was fabricated to test the feasibility of the proposed design. The prototype showed gravity balancing and was tested by the authors. This prototype will be modified appropriately for clinical testing.
Kinematic Synthesis for Finitely Separated Positions Using Geometric Constraint Programming
Authors: Kinzel Edward C. , Schmiedeler James P. , Pennock Gordon R.
Published: August 2006

This paper presents an original approach to the kinematic synthesis of planar mechanisms for finitely separated positions. The technique, referred to here as geometric constraint programming, uses the sketching mode of commercial parametric computer-aided design software to create kinematic diagrams. The elements of these diagrams are parametrically related so that when a parameter is changed, the design is modified automatically. Geometric constraints are imposed graphically through a well-designed user interface, and numerical solvers integrated into the software solve the relevant systems of equations without the user explicitly formulating those equations. This allows robust algorithms for the kinematic synthesis of a wide variety of mechanisms to be “programmed” in a straightforward, intuitive manner. The results provided by geometric constraint programming exhibit the accuracy and repeatability achieved with analytical synthesis techniques, while simultaneously providing the geometric insight developed with graphical synthesis techniques. The key advantages of geometric constraint programming are that it is applicable to a broad range of kinematic synthesis problems, user friendly, and highly accessible. To demonstrate the utility of the technique, this paper applies geometric constraint programming to three examples of the kinematic synthesis of planar four-bar linkages: Motion generation for five finitely separated positions, path generation for nine finitely separated precision points, and function generation for four finitely separated positions.
Identifying and Counting the Number of Mechanisms From Kinematic Chains Subject to Design Constraints
Authors: Yan Hong-Sen , Hung Chih-Ching
Published: August 2006

An approach is presented, based on combinatorial theory, for the complete enumeration of nonisomorphic mechanisms precisely from kinematic chains. And, based on the permutation groups, the concept of the generating function, and Polya’s Theory, mathematical expressions are derived for counting the number of the identified mechanisms subject to the design constraints of the adjacent/incident relationship among links, joints, or links and joints. Examples are provided to illustrate the proposed approach. The results of this work can instead of the observation method to inspect the isomorphism for mechanisms; furthermore, all nonisomorphic mechanisms can be obtained exactly and systematically.
Response to Comment on "Gene Regulatory Networks and the Evolution of Animal Body Plans"
Authors: Erwin Douglas H. , Davidson Eric H.
Published: August 2006

Contrary to Coyne's assertions, our paper did not advocate a macromutational innovation of phyla but considered the consequences of the introduction of developmental constraints for the evolution of gene regulatory networks based on recent empirical studies of gene regulatory networks.
How and Why Do Insects Migrate?
Authors: Holland Richard A. , Wikelski Martin , Wilcove David S.
Published: August 2006

Countless numbers of insects migrate within and between continents every year, and yet we know very little about the ultimate reasons and proximate mechanisms that would explain these mass movements. Here we suggest that perhaps the most important reason for insects to migrate is to hedge their reproductive bets. By spreading their breeding efforts in space and time, insects distribute their offspring over a range of environmental conditions. We show how the study of individual long-distance movements of insects may contribute to a better understanding of migration. In the future, advances in tracking methods may enable the global surveillance of large insects such as desert locusts.
Magnetic Fields in the Formation of Sun-Like Stars
Authors: Girart Josep M. , Rao Ramprasad , Marrone Daniel P.
Published: August 2006

We report high-angular-resolution measurements of polarized dust emission toward the low-mass protostellar system NGC 1333 IRAS 4A. We show that in this system the observed magnetic field morphology is in agreement with the standard theoretical models of the formation of Sun-like stars in magnetized molecular clouds at scales of a few hundred astronomical units; gravity has overcome magnetic support, and the magnetic field traces a clear hourglass shape. The magnetic field is substantially more important than turbulence in the evolution of the system, and the initial misalignment of the magnetic and spin axes may have been important in the formation of the binary system.
On Smell and Scientific Practice
Authors: Solomon Miriam
Published: August 2006

The Secret of Scent
. Adventures in Perfume and the Science of Smell.
By Luca Turin
. Faber and Faber, London, 2006. 217 pp. £12.99. ISBN 0-571-21537-8. Forthcoming from Ecco, New York. ISBN 0-06-113383-3.

A biophysicist and perfume critic describes his obsession with olfaction and his controversial theory that we smell primarily by detecting the vibrational frequency of molecules.
Weather-related patterns of fruit abscission mask patterns of frugivory
Authors: Bartuszevige Anne M. , Hughes Michael R. , Bailer A. John , Gorchov David L.
Published: August 2006

Previous studies on frugivory in temperate bird-dispersed plants have concluded that fleshy fruits are removed more rapidly in cold than in warm winters. However, these studies do not distinguish between fruit abscission and frugivory. The implicit assumption that fruit loss reflects frugivory may not be valid; fruit abscission may be important and respond differently to weather. During two winters, we measured fruit loss from an invasive shrub ( Lonicera maackii (Rupr.) Herder) using fruit traps. We examined the effects of temperature and precipitation on fruit retention on shrubs and fruit abscission. In the first year of our study, there was no effect of temperature or precipitation on fruit retention. In the second year, both warmer temperatures and lower precipitation resulted in more fruit retention. In both years, fruit abscission was greater during periods of cold temperatures and high precipitation. These findings suggest that weather-dependent “frugivory” reported for other bird-dispersed plants may actually reflect patterns of abscission.
Experimental demonstration of floral allocation costs in Crepis tectorum
Authors: Andersson Stefan
Published: August 2006

Information on floral resource costs is fundamental for understanding how selection operates on floral morphology. In this study, I explored the cost of maturing flowers in a self-incompatible population of the ligulate composite Crepis tectorum L. by experimentally manipulating floral investment and then monitoring the response in reproductive effort. Plants on which the heads were removed during the initial stage of ligule expansion had a higher reproductive effort than plants whose heads were removed immediately after flower maturation, and the latter plants had a higher reproductive effort than plants on which all flowers were permitted to set fruit. Judging from biomass estimates and the magnitude of the observed tradeoffs, the amount of resources allocated to maturing flowers was about half as great as the amount of resources devoted to fruit maturation. These and other results suggest that floral tradeoffs may exert negative selection on floral size variables.
Sources of spatial and temporal heterogeneity in the colonization of an alpine krummholz environment by the weedy subalpine plant Chamerion angustifolium (fireweed)
Authors: Dona Amy J. , Galen Candace
Published: August 2006

Plant–plant interactions may increase or reduce the impact of abiotic stress on species' distributions, depending on the balance between competition and facilitation. We report on the role of a willow ( Salix ) shrub canopy in mediating the importance of drought stress for performance at seedling and adult life stages of the herbaceous wildflower, Chamerion angustifolium L. (fireweed). Willows form the vegetative boundary (krummholz) between subalpine and alpine life zones in the Rocky Mountains. Chamerion angustifolium is a weedy pioneer species common in subalpine vegetation and advancing upward into the krummholz in the central Rocky Mountains. A mosaic of soil moisture variation dictated spatial patterns of seed germination and seedling survival in C. angustifolium in the absence of willows. However, willows restricted the capacity of C. angustifolium to exploit natural patches of soil moisture during establishment. Seed germination, seedling survival, and net establishment success increased markedly with soil water supply in the open, but not under the willow canopy. For mature plants, willows restricted photosynthesis at the peak of the growing season when rainfall was frequent, but ameliorated the daily decline in leaf water status under drought late in the season. Results suggest that the impact of willows on desiccation stress in alpine populations of fireweed varies with life history stage and phenology.
Simulated weathering of dinosaur tracks and the implications for their characterization
Authors: Henderson Donald M
Published: August 2006

Digital models of the tracks of bipedal theropod and ornithopod dinosaurs, and the quadrupedal tracks of a sauropod, were computationally eroded to investigate the effects of erosion on the shapes, sizes, and diagnostic details of fossil tracks. Narrow and (or) angular details, such as claw marks, interdigital ridges, and internal ridges, are removed early in erosion, creating the potential for misidentification of eroded theropod tracks as those of ornithopods. However, with the erosion models presented here, all tracks retain their basic shapes as indicated by the relative constancy of their interdigital angles and by the relative constancy of their footlength:footwidth ratios. Surface lengths of tracks did not increase significantly with erosion, so that dinosaurian hip height and speed estimates derived from trackways would not be greatly in error if based on eroded surface tracks. Synthetic undertracks from the surface tracks were also produced using information from published physical models of track formation. The differences between a weathered surface track and a freshly exposed, simulated undertrack are sufficient so that the two model tracks would not be confused. Large, rounded tracks are much better at retaining their characteristics than small, angular tracks, with the implication that large tracks may be over-represented in the fossil record, but they may be more reliably attributed to the appropriate trackmaker. This would bias estimates of dinosaur taxonomic diversity and body size ranges based on trackway evidence.
The effects of isolation and colonization history on the genetic structure of marine-relict populations of Atlantic cod (Gadus morhua) in the Canadian Arctic
Authors: Hardie David C , Gillett Roxanne M , Hutchings Jeffrey A
Published: August 2006

The genetic consequences of extended periods at low population size are fundamental to the conservation of depleted species such as the Atlantic cod (Gadus morhua). We compared microsatellite genetic variability among cod populations in Canadian Arctic lakes with that of Gilbert Bay resident and inshore cod from eastern Canada. The Arctic populations had the lowest genetic diversity and were the most strongly genetically structured and distinct. By contrast, eastern Canadian samples expressed high allelic diversity and were not significantly genetically structured or distinct relative to each other, whereas Gilbert Bay resident cod were intermediate to the Arctic and eastern Canadian groups. Our results are consistent with the hypothesis that the Arctic populations were colonized between 8000 and 5000 years ago and have experienced little or no gene flow since that time. Despite isolation at the extreme of the species' range, the Arctic populations have retained relatively high heterozygosities and high genetic effective population sizes relative to census sizes (Ne–Ncratios). Potential explanations for this include the absence of fishing pressure, allowing for the persistence of large, highly fecund individuals, as well as biotic (e.g., absence of planktivores) and abiotic (e.g., low environmental stochasticity) factors in the Arctic lakes that minimize individual variance in reproductive success.