bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of combined strength and kick coordination training on soccer kick biomechanics in amateur players
Authors: Manolopoulos E. , Papadopoulos C. , Kellis E.
Published: January 2006

The aim of this study was to examine the effect of a soccer (strength and technique) training program on kinematics and electromyographic (EMG) muscle activity during a instep kick. Ten amateur soccer players (aged 19.9±0.4 years, body mass 74.8±9.1 kg, height 177.4±6.7 cm) constituted the experimental group (EG) whereas 10 players (age 21.6±1.3 years, weight 71.5±6.7 kg, height 175.2±3.4 cm) served as controls (CG). The EG followed a 10‐week soccer‐specific training program combining strength and technique exercises. All participants performed an instep soccer kick using a two‐step approach while three‐dimensional data and EMG from six muscles of swinging and support legs were recorded prior to and after training. Maximum isometric leg press strength, 10‐m sprint performance and maximum speed performance on a bicycle ergometer were also measured. Analysis of variance designs with repeated measures showed that the EG improved significantly (P<0.05) maximum ball speed, the linear velocity of the foot, ankle and angular velocity of all joints during the final phase of the kick. Training had insignificant effects on EMG values, apart from an increase in the averaged EMG of the vastus medialis whereas maximum isometric strength and sprint times significantly improved after training (P<0.05). The present results suggest that the application of the training programs using soccer‐specific strength exercises would be particularly effective in improving of soccer kick performance.
Exercise‐induced rib stress fractures: potential risk factors related to thoracic muscle co‐contraction and movement pattern
Authors: Vinther A. , Kanstrup I.‐L. , Christiansen E. , Alkjær T. , Larsson B. , Magnusson S. P. , Ekdahl C. , Aagaard P.
Published: January 2006

The etiology of exercise‐induced rib stress fractures (RSFs) in elite rowers is unclear. The purpose of the study was to investigate thoracic muscle activity, movement patterns and muscle strength in elite rowers. Electromyographic (EMG) and 2‐D video analysis were performed during ergometer rowing, and isokinetic muscle strength was measured in seven national team rowers with a history of RSF and seven matched controls (C).

RSF displayed a higher velocity of the seat in the initial drive phase (RSF: 0.25±0.03, 0.25 (0.15–0.33) m/s vs C: 0.15±0.06, 0.18 (−0.11–0.29) m/s P=0.028) (Mean±SEM, median and range). Further, RSF had greater co‐contraction of m. serratus anterior and m. trapezius in the mid‐drive phase (RSF: 47.5±3.4, 48.5 (35.8–60.2)% EMG signal overlap vs C: 30.8±6.5, 27.0 (11.2–61.6)%P=0.043). In addition, the RSF subjects showed a lower knee‐extension to elbow‐flexion strength ratio (RSF: 4.2±0.22, 4.3 (3.5–5.1) vs C: 4.8±0.16, 5.0 (4.2–5.3) P=0.043), indicating stronger arms relative to legs compared with controls. In conclusion, increased thoracic muscle co‐contraction, altered movement patterns and reduced leg/arm strength ratio were observed in the RSF subjects, which may all predispose toward an increased risk of RSF.
Voluntary activation and central activation failure in the knee extensors in young women and men
Authors: Miller M. , Holmbäck A. M. , Downham D. , Lexell J.
Published: January 2006

Quadriceps muscle weakness is common after knee injuries. This weakness is caused, in part, by reduced voluntary activation (VA) because of central activation failure (CAF). Superimposed electrical stimulation techniques are used to assess VA and to detect CAF. The aim of this study was to assess VA during knee extension in young healthy women and men, and to evaluate subjective discomfort from the electrical stimulation. The quadriceps muscle in six young healthy women (mean age 22 years) and six young healthy men (mean age 29 years) was stimulated during maximal voluntary contractions using a 100 Hz pulse train. Data were collected from two test sessions separated by 6–8 days and each session comprised of two trials. A visual analog scale for pain (VAS‐pain) was used to evaluate subjective discomfort. Overall, young healthy, moderately active men and women did have the ability to fully activate their knee extensors isometrically, but they did not achieve full activation on every trial. In those trials where a CAF was detected, the degree was small (mean less than 2%), and did not vary between the two test sessions. Subjective discomfort was generally moderate and tolerable (mean VAS‐pain score 35 mm). These results will assist the clinical assessment of muscle weakness following a knee injury and facilitate the design and evaluation of appropriate rehabilitation interventions.
Whole‐body fat oxidation determined by graded exercise and indirect calorimetry: a role for muscle oxidative capacity?
Authors: Nordby P. , Saltin B. , Helge J. W.
Published: January 2006

During whole‐body exercise, peak fat oxidation occurs at a moderate intensity. This study investigated whole‐body peak fat oxidation in untrained and trained subjects, and the presence of a relation between skeletal muscle oxidative enzyme activity and whole‐body peak fat oxidation. Healthy male subjects were recruited and categorized into an untrained (N=8, VO2max 3.5±0.1 L/min) and a trained (N=8, VO2max 4.6±0.2 L/min) group. Subjects performed a graded exercise test commencing at 60 W for 8 min followed by 35 W increments every 3 min. On a separate day, muscle biopsies were obtained from vastus lateralis and a 3 h bicycle exercise test was performed at 58% of VO2max. Whole‐body fat oxidation was calculated during prolonged and graded exercise from the respiratory exchange ratio using standard indirect calorimetry equations. Based on the graded exercise test, whole‐body peak fat oxidation was determined. The body composition was determined by DEXA.

Whole‐body peak fat oxidation (250±25 and 462±33 mg/min) was higher (P<0.05) and occurred at a higher (P<0.05) relative workload (43.5±1.8% and 49.9±1.2% VO2max) in trained compared with untrained subjects, respectively. Muscle citrate synthase activity and β‐hydroxy‐acyl‐CoA‐dehydrogenase activity were higher (49% and 35%, respectively, P<0.05) in trained compared with untrained subjects. Both lean body mass and maximal oxygen uptake were significantly correlated to whole‐body peak fat oxidation (r2=0.57, P<0.001), but leg muscle oxidative capacity was not correlated to whole‐body peak fat oxidation.

In conclusion, whole‐body peak fat oxidation occurred at a higher relative exercise load in trained compared with untrained subjects. Whole‐body peak fat oxidation was not significantly related to leg muscle oxidative capacity, but was related to lean body mass and maximal oxygen uptake. This may suggest that leg muscle oxidative activity is not the main determinant of whole‐body peak fat oxidation.
FGF signalling in craniofacial development and developmental disorders
Authors: Nie X , Luukko K , Kettunen P
Published: January 2006

The Fgf signalling pathway is highly conserved in evolution and plays crucial roles in development. In the craniofacial region, it is involved in almost all structure development from early patterning to growth regulation. In craniofacial skeletogenesis, the Fgf signal pathway plays important roles in suture and synchondrosis regulation. Mutations of FGF receptors relate to syndromatic and non‐syndromatic craniosynostosis. The Fgf10/Fgfr2b signal loop is critical for palatogenesis and submandibular gland formation. Perturbation of the Fgf signal is a possible mechanism of palatal cleft. Fgf10 haploinsufficiency has been identified as the cause of autosomal dominant aplasia of lacrimal and salivary glands. The Fgf signal is also a key regulator of tooth formation: in the absence of Fgfr2b tooth development is arrested at the bud stage. Fgfr4 has recently been identified as the key signal mediator in myogenesis. In this review, these aspects are discussed in detail with a focus on the most recent advances.
Cephalometric evaluation of condylar and mandibular growth modification: a review
Authors: Shen G , Darendeliler MA
Published: January 2006

Structured Abstract

Authors – Shen G, Darendeliler MA

Objective – Based on a wealth of orthodontic archives, this work aims to review the cephalometric analysis systems that can identify the changes in condylar and mandibular position as well as growth direction in response to bite jumping therapy.

Design – Numerous cephalometric approaches were screened to testify their feasibility and reliability in accurately depicting the growth modification of the condyle and the mandible. The critical assessment of the working mechanisms of these cephalometric methods was elaborated to help build up the rationale and justification for their clinical use.

Results – 1) The changes in condylar and mandibular size, position and growth direction can be identified by using lateral cephalograms with closed‐mouth or open‐mouth posture. 2) With superimposition methods where the anatomical structures for superimposition registration must be stable and reproducible, the growth modification of the condyle and the mandible between two time‐points is qualitatively demonstrated in a diagram if reference lines are not constructed. The growth modification can be quantitatively identified if the reference lines are created. 3) With non‐superimposition methods, the size and position of the condyle and the mandible are separately identified for each time‐pint by relating them to the stable reference structures. The growth modification between two time‐pints is evaluated by comparing the two separate measurements.

Conclusion – The application of a standardized and well designed cephalometric evaluation system may reduce the bias that attribute to the arbitrariness of the clinical effects of bite jumping functional appliances.
Parental craniofacial morphology in cleft lip with or without cleft palate as determined by cephalometry: a meta‐analysis
Authors: Weinberg SM , Maher BS , Marazita ML
Published: January 2006

Structured Abstract

Authors – Weinberg SM, Maher BS, Marazita ML

Objective – To integrate findings from previous cephalometric studies comparing the craniofacial complex of unaffected parents with cleft lip with or without cleft palate (CL/P) children to controls with no history of the disease.

Design – Meta‐analysis of case‐control cephalometric data.

Inclusion criteria – Studies were selected if the unaffected parents of children with CL/P were included and were not combined with parents of children with isolated CP; quantitative data were obtained through cephalometry; the cephalometric variables used were not unique to a study; a case‐control design was used; and the means and standard deviations for all variables were reported or could be calculated for both the experimental and the control group.

Outcome measure – Using raw data obtained from nine studies, mean weighted effect sizes with 95% confidence intervals were calculated for 28 cephalometric variables (mothers and fathers combined) or 18 variables (mothers and fathers separately). Heterogeneity statistics for the effect sizes were also calculated.

Results – In general, unaffected parents of children with CL/P possessed significantly wider interorbital, nasal cavity and upper facial dimensions, narrower cranial vaults, longer cranial bases, longer and more protrusive mandibles, shorter upper faces and longer lower faces compared with controls. Increased width of the nasal cavity was the most robust finding. Significant effect size heterogeneity was observed in roughly half of the variables examined.

Conclusion – Unaffected parents of children with CL/P are characterized by a suite of consistent, yet subtle, craniofacial differences, which could indicate an underlying genetic liability.
Alkaline phosphatase activity in gingival crevicular fluid during canine retraction
Authors: Batra P , Kharbanda OP , Duggal R , Singh N , Parkash H
Published: January 2006

Structured Abstract

Authors –  Batra P, Kharbanda OP, Duggal R, Singh N, Parkash H

Objectives –  The aim of the study was to investigate alkaline phosphatase activity in the gingival crevicular fluid (GCF) during orthodontic tooth movement in humans.

Setting and Sample Population –  Postgraduate orthodontic clinic. Ten female patients requiring all first premolar extractions were selected and treated with standard edgewise mechanotherapy.

Experimental Variable –  Canine retraction was done using 100 g sentalloy springs. Maxillary canine on one side acted as experimental site while the contralateral canine acted as control.

Outcome Measure –  Gingival crevicular fluid was collected from mesial and distal of canines before initiation of canine retraction (baseline), immediately after initiation of retraction, and on 1st, 7th, 14th and 21st day and the alkaline phosphatase activity was estimated.

Results –  The results show significant (p < 0.05) changes in alkaline phosphatase activity on the 7th, 14th and 21st day on both mesial and distal aspects of the compared experimental and control sides. The peak in enzyme activity occurred on the 14th day of initiation of retraction followed by a significant fall in activity especially on the mesial aspect.

Conclusions –  The study showed that alkaline phosphatase activity could be successfully estimated in the GCF using calorimetric estimation assay kits. The enzyme activity showed variation according to the amount of tooth movement.
Early Treatment of Cavernositis Resulted in Erectile Function Preservation
Authors: Shamloul Rany , Kamel Ihab
Published: January 2006

Introduction

Some of the more common complications of intracavernous injection (ICI) therapy include pain and prolonged erections. Rare reported complications include intracorporeal needle breakage and postinjection cavernositis.

Aim

We report a case of early management of postinjection cavernositis resulting in preservation of erectile function with no angulation.

Methods

A 53-year-old male with no history of diabetes mellitus presented to our department with a small painful penile swelling 36 hours after ICI of 15 µg prostaglandin E1. Clinical, laboratory, and ultrasound assessments suggested the occurrence of cavernositis. Surgical debridement, abscess drainage, and antibiotics resulted in marked improvement. Follow-up showed normal erectile function with minimal scarring.

Conclusions

Timely management of cavernositis can help prevent loss of erectile function. Stringent supervision of patients, after adequate ICI training, together with drug prescription, is essential.
Evidence for linkage and association between autoimmune thyroid diseases and the 18q12–q21 region in a large Tunisian family
Authors: Hadj Kacem H. , Rebai A. , Kaffel N. , Abid M. , Ayadi H.
Published: January 2006

Many studies have shown linkage between IDDM6 locus on 18q12–q21 chromosome and several autoimmune diseases, suggesting that it might harbour susceptibility genes common to autoimmunity. Using 12 families deriving from a large Tunisian multiplex family (the Akr family) from which 38 people were affected with autoimmune thyroid diseases (AITD), and 193 unrelated AITD patients, tested against 100 healthy subjects, we tried to replicate the positive results previously reported for the IDDM6. Akr members were genotyped with eight microsatellite markers harbouring the IDDM6 region. Multipoint non‐parametric linkage analysis have shown a clear peak values of NPL score around D18S41 marker (Z = 3.72, P = 0.0001). Family‐based association test (FBAT) and transmission disequilibrium test (TDT) have confirmed linkage results. In particular, a significant association with allele 3 of D18S41 and allele 2 of D18S57 markers was found. Case–control studies, using one intragenic microsatellite (locus CTG18.1) marker in the immunoglobulin transcription factor (ITF2) gene, a 5′ flanking AC repeat of the anti‐apoptotic BCL‐2 gene as well as two SNPs at positions +52 and +1955 from transcription start site of BCL‐2, showed no significant association between neither genes and AITD. Our study is the first replication of the 18q12–q21 chromosome region as a potential candidate to AITD genetic susceptibility. The Akr family has shown evidence for linkage between IDDM6 locus and AITD. Moreover, case–control study does not support the involvement of ITF2 and BCL2 genes in AITD pathogenesis.
Global distribution of a novel trinucleotide microsatellite polymorphism (ATA)n in intron 8 of the SLC11A1 gene and susceptibility to pulmonary tuberculosis
Authors: Awomoyi A. , Sirugo G. , Newport M. J. , Tishkoff S.
Published: January 2006

We identified a novel trinucleotide (ATA)n repeat polymorphism in intron 8 of SLC11AI, a candidate gene for susceptibility to tuberculosis (TB) infection. We characterized the frequency of this polymorphism in 485 individuals originating from eight globally diverse human populations and compared the distribution of (ATA)n alleles in 146 adults and in 80 cord blood samples from newborns in the Gambian population. Lastly, we tested for association of this microsatellite with pulmonary TB in 318 TB cases and 146 controls in the Gambian population. We found no significant difference in frequency or distribution of alleles in adult and cord blood samples, and we found no significant association between this marker and pulmonary TB.
The role of HLA molecules in susceptibility to chronic rheumatic heart disease
Authors: Kudat H. , Telci G. , Sozen A. B. , Oguz F. , Akkaya V. , Ozcan M. , Atilgan D. , Carin M. , Guven O.
Published: January 2006

Only a small fraction of the streptococcal pharyngitis progress to rheumatic carditis, which implies that environmental, host and microbial factors interact to cause an aberrant immune response against the antigens of the microorganism that cross‐react with cardiac tissues. Although there are numerous studies and a general consensus on the relation between human leucocyte antigen (HLA) class II antigens and rheumatic heart disease (RHD), the details and the culprit antigens are still controversial. The study was undertaken to examine 100 patients with chronic RHD and 100 controls for HLA class I and class II antigens for differences in prevalence. All samples were typed at the HLA‐DRB1/3/4/5 and DQB1 loci by the sequence‐specific primer (PCR‐SSP) method at low resolution. For HLA class I antigens, HLA‐B13 frequency was marginally increased in patients with RHD compared to controls without reaching statistical significance. For class II antigens, RHD patients had higher frequencies for HLA‐DRB1*01 (RHD 24%, controls 10%), DRB1*04 (RHD 35%, controls 26%), DRB1*07 (RHD 18%, controls 11%) and HLA‐DQB1*02 (RHD 32%, controls 17%) without reaching statistical significance, and significantly lower frequencies for DRB1*13 (Pc < 0.003, OR: 5.69), DRB5* (Pc < 0.003, OR: 33) and DRB3* (Pc = 0.03, OR: 2.66) compared to controls. It was concluded that host, microbial and environmental factors collude to create acute rheumatic fever (RF) and chronic rheumatic valve disease. The HLA‐DRB1*13, DRB5* and DRB3* were protective against the development of rheumatic valve damage.
Ethics of international clinical research collaboration — the experience of AlloStem
Authors: Chaplin C.
Published: January 2006

This paper examines the ethics of international clinical collaboration in stem cell research by focusing on the AlloStem project. AlloStem is an international research programme, financed by the European Union under the Sixth Framework Programme, with the aim of advancing the use of stem cells in treating leukaemia and other haematological diseases. Several areas of ethical importance are explored. Research justification and the need to consider both deontological and teleological aspects are examined. Ethical sensitivity in research and the requirement to respond to areas of ethical concern identified by the European Commission, such as the involvement of human beings, the use of human tissue, and the use of animals are also explored. Ethical issues around project structure and management, such as ethical standardization in international research, and achieving set targets are discussed. The ethical importance of dissemination of findings and teaching in clinical research is also considered. Finally, the distribution of benefits is addressed and the importance of distributive justice is emphasized.
Metric Damping of MDOF Systems in High Transient Motion
Authors: Al Majid A. , Allezy A. , Dufour R.
Published: January 2006

This paper deals with damping due to transient motion in the case of multi-degree-of-freedom (MDOF) system. The main aim of this research is to make the method presented by the authors in a previous paper available for MDOF systems. An method based on relativity concepts is developed in order to identify and evaluate a metric damping due to time-varying forcing frequency. An additional dimension for each degree of freedom (DOF) is introduced. The variational problem of the metric of a Riemannian space gives the geodesic equations, i.e., equations of motion that, after time integration carried out with several types of numerical schemes, permit one to predict the forced transient response of a 3-DOF system. The proposed metric approach makes the experimental results correspond with the simulated results.
Determination of Ultrasound Phase Velocity in Trabecular Bone Using Time Dependent Phase Tracking Technique
Authors: Lin Wei , Mittra Erik , Qin Yi-Xian
Published: January 2006

Ultrasound velocity is one of the key acoustic parameters for noninvasive diagnosis of osteoporosis. Ultrasound phase velocity can be uniquely measured from the phase of the ultrasound signal at a specified frequency. Many previous studies used fast Fourier transform (FFT) to determine the phase velocity, which may cause errors due to the limitations of FFT. The new phase tracking technique applied an adaptive tracking algorithm to detect the time dependent phase and amplitude of the ultrasound signal at a specified frequency. This overcame the disadvantages of FFT to ensure the accuracy of the ultrasound phase velocity. As a result, the new method exhibited high accuracy in the measurement of ultrasound phase velocity of two phantom blocks with the error less than 0.4%. 41 cubic trabecular samples from sheep femoral condyles were used in the study. The phase velocity of the samples using the new method had significantly high correlation to the bulk stiffness of the samples (r=0.84) compared to the phase velocity measured using fast Fourier transform FFT (r=0.14). In conclusion, the new method provided an accurate measurement of the ultrasound phase velocity in bone.
3D Finite Element Model of Meniscectomy: Changes in Joint Contact Behavior
Authors: Zielinska Barbara , Haut Donahue Tammy L.
Published: January 2006

The goal of this study is to quantify changes in knee joint contact behavior following varying degrees of the medial partial meniscectomy. A previously validated 3D finite element model was used to simulate 11 different meniscectomies. The accompanying changes in the contact pressure on the superior surface of the menisci and tibial plateau were quantified as was the axial strain in the menisci and articular cartilage. The percentage of medial meniscus removed was linearly correlated with maximum contact pressure, mean contact pressure, and contact area. The lateral hemi-joint was minimally affected by the simulated medial meniscectomies. The location of maximum strain and location of maximum contact pressure did not change with varying degrees of partial medial meniscectomy. When 60% of the medial meniscus was removed, contact pressures increased 65% on the remaining medial meniscus and 55% on the medial tibial plateau. These data will be helpful for assessing potential complications with the surgical treatment of meniscal tears. Additionally, these data provide insight into the role of mechanical loading in the etiology of post-meniscectomy osteoarthritis.
A New Drift-Flux Model for Particle Transport and Deposition in Human Airways
Authors: Wang J. B. , Lai Alvin C. K.
Published: January 2006

Particle deposition and transport in human airways is frequently modeled numerically by the Lagrangian approach. Current formulations of such models always require some ad hoc assumptions, and they are computationally expensive. A new drift-flux model is developed and incorporated into a commercial finite volume code. Because it is Eulerian in nature, the model is able to simulate particle deposition patterns, distribution and transport both spatially and temporally. Brownian diffusion, gravitational settling, and electrostatic force are three major particle deposition mechanisms in human airways. The model is validated against analytical results for three deposition mechanisms in a straight tube prior to applying the method to a single bifurcation G3-G4. Two laminar flows with Reynolds numbers 500 and 2000 are simulated. Particle concentration contour, deposition pattern, and enhancement factor are evaluated. To demonstrate how the diffusion and settling influence the deposition and transport along the bifurcation, particle sizes from 1nmto10μm are studied. Different deposition mechanisms can be combined into the mass conversation equation. Combined deposition efficiency for the three mechanisms simultaneously was evaluated and compared with two commonly used empirical expressions.
Flow and Thrombosis at Orifices Simulating Mechanical Heart Valve Leakage Regions
Authors: Fallon Anna M. , Shah Nisha , Marzec Ulla M. , Warnock James N. , Yoganathan Ajit P. , Hanson Stephen R.
Published: January 2006

Background: While it is established that mechanical heart valves (MHVs) damage blood elements during leakage and forward flow, the role in thrombus formation of platelet activation by high shear flow geometries remains unclear. In this study, continuously recalcified blood was used to measure the effects of blood flow through orifices, which model MHVs, on the generation of procoagulant thrombin and the resulting formation of thrombus. The contribution of platelets to this process was also assessed. Method of Approach: 200, 400, 800, and 1200μm orifices simulated the hinge region of bileaflet MHVs, and 200, 400, and 800μm wide slits modeled the centerline where the two leaflets meet when the MHV is closed. To assess activation of coagulation during blood recirculation, samples were withdrawn over 0-47min and the plasmas assayed for thrombin-antithrombin-III (TAT) levels. Model geometries were also inspected visually. Results: The 200 and 400μm round orifices induced significant TAT generation and thrombosis over the study interval. In contrast, thrombin generation by the slit orifices, and by the 800 and 1200μm round orifices, was negligible. In additional experiments with nonrecalcified or platelet-depleted blood, TAT levels were markedly reduced versus the studies with fully anticoagulated whole blood (p<0.05). Conclusions: Using the present method, a significant increase in TAT concentration was found for 200 and 400μm orifices, but not 800 and 1200μm orifices, indicating that these flow geometries exhibit a critical threshold for activation of coagulation and resulting formation of thrombus. Markedly lower TAT levels were produced in studies with platelet-depleted blood, documenting a key role for platelets in the thrombotic process.
Two-Phase Computerized Planning of Cryosurgery Using Bubble-Packing and Force-Field Analogy
Authors: Tanaka Daigo , Shimada Kenji , Rabin Yoed
Published: January 2006

Background : Cryosurgery is the destruction of undesired tissues by freezing, as in prostate cryosurgery, for example. Minimally invasive cryosurgery is currently performed by means of an array of cryoprobes, each in the shape of a long hypodermic needle. The optimal arrangement of the cryoprobes, which is known to have a dramatic effect on the quality of the cryoprocedure, remains an art held by the cryosurgeon, based on the cryosurgeon’s experience and “rules of thumb.” An automated computerized technique for cryosurgery planning is the subject matter of the current paper, in an effort to improve the quality of cryosurgery. Method of Approach: A two-phase optimization method is proposed for this purpose, based on two previous and independent developments by this research team. Phase I is based on a bubble-packing method, previously used as an efficient method for finite element meshing. Phase II is based on a force-field analogy method, which has proven to be robust at the expense of a typically long runtime. Results: As a proof-of-concept, results are demonstrated on a two-dimensional case of a prostate cross section. The major contribution of this study is to affirm that in many instances cryosurgery planning can be performed without extremely expensive simulations of bioheat transfer, achieved in Phase I. Conclusions: This new method of planning has proven to reduce planning runtime from hours to minutes, making automated planning practical in a clinical time frame.
Comparison of the Linear Finite Element Prediction of Deformation and Strain of Human Cancellous Bone to 3D Digital Volume Correlation Measurements
Authors: Zauel R. , Yeni Y. N. , Bay B. K. , Dong X. N. , Fyhrie D. P.
Published: January 2006

The mechanical properties of cancellous bone and the biological response of the tissue to mechanical loading are related to deformation and strain in the trabeculae during function. Due to the small size of trabeculae, their motion is difficult to measure. To avoid the need to measure trabecular motions during loading the finite element method has been used to estimate trabecular level mechanical deformation. This analytical approach has been empirically successful in that the analytical models are solvable and their results correlate with the macroscopically measured stiffness and strength of bones. The present work is a direct comparison of finite element predictions to measurements of the deformation and strain at near trabecular level. Using the method of digital volume correlation, we measured the deformation and calculated the strain at a resolution approaching the trabecular level for cancellous bone specimens loaded in uniaxial compression. Smoothed results from linearly elastic finite element models of the same mechanical tests were correlated to the empirical three-dimensional (3D) deformation in the direction of loading with a coefficient of determination as high as 97% and a slope of the prediction near one. However, real deformations in the directions perpendicular to the loading direction were not as well predicted by the analytical models. Our results show, that the finite element modeling of the internal deformation and strain in cancellous bone can be accurate in one direction but that this does not ensure accuracy for all deformations and strains.
Rotor Vibration Measurements Using Laser Doppler Vibrometry: Essential Post-Processing for Resolution of Radial and Pitch/Yaw Vibrations
Authors: Halkon Ben J. , Rothberg Steve J.
Published: January 2006

Laser Doppler vibrometry is now a well established technique enabling noncontact vibration measurements in the most challenging of environments. Rotor vibration measurements are often highlighted as a major application of laser vibrometers due to their noncontact operation and inherent immunity to shaft runout. In such measurements, resolution of the individual axial and torsional vibration components is possible via particular arrangement of the laser beam(s). Resolution of the radial or pitch/yaw vibration components, however, can only be achieved by essential post-processing of the data from simultaneous orthogonal measurements. This paper describes the principle and rigorous examination of a novel, dedicated resolution algorithm enabling, for the first time, real-time post-processing of the outputs from standard commercial instruments. The system performed well, even in the presence of noise and other typical measurement errors, and was implemented successfully in an engine vibration study.
Grazing and Chaos in a Periodically Forced, Piecewise Linear System
Authors: Luo Albert C. J.
Published: January 2006

The criteria for the grazing bifurcation of a periodically forced, piecewise linear system are developed and the initial grazing manifolds are obtained. The initial grazing manifold is invariant. The grazing flows are illustrated to verify the analytic prediction of grazing. The mechanism of the strange attractors fragmentation caused by the grazing is discussed, and an illustration of the fragmentized strange attractor is given through the Poincaré mapping. This fragmentation phenomenon exists extensively in nonsmooth dynamical systems. The mathematical structure of the fragmentized strange attractors should be further developed.
Structronics and Actuation of Hybrid Electrostrictive/Piezoelectric Thin Shells
Authors: Tzou H. S. , Chai W. K. , Arnold S. M.
Published: January 2006

Certain ferroelectric materials possess dual electrostrictive and piezoelectric characteristics, depending on their specific Curie temperatures. The nonlinear electro-mechanical effect of electrostrictive materials provides stronger actuation performance as compared with that of piezoelectric materials. Due to the complexity of the generic ferroelectric actuators, micro-electromechanics, structure-electronic (structronic) coupling and control characteristics of hybrid electrostrictive/piezoelectric dynamic systems deserve an in-depth investigation. In this study, dynamic electro-mechanical system equations and boundary conditions of hybrid electrostrictive/piezoelectric double-curvature shell continua are derived using the energy-based Hamilton’s principle, elasticity theory, electrostrictive/piezoelectric constitutive relations, and Gibb’s free energy function. These governing equations clearly reveal the coupling of electrostrictive, piezoelectric, and elastic fields and characteristics change triggered by the Curie temperature. The electric terms are used to manipulate and to control the static/dynamic behavior of hybrid electrostrictive/piezoelectric shells. To apply the hybrid shell system equations to other geometries, simplification procedures using two Lamé parameters and two radii of curvature are demonstrated in two cases: A hybrid electrostrictive/piezoelectric conical shell and a hybrid electrostrictive/piezoelectric toroidal shell. Following the same procedures, one can apply the generic system equations to other common geometries, e.g., beams, arches, plates, rings, cylindrical shells, spherical shells, etc., or specific materials, e.g., electrostrictive or piezoelectric, and further evaluate their electromechanical characteristics and actuation/control effectiveness.
Organisational injustice and impaired cardiovascular regulation among female employees
Authors: Elovainio M , Kivimäki M , Puttonen S , Lindholm H , Pohjonen T , Sinervo T
Published: January 2006

Objectives:To examine the relation between perceived organisational justice and cardiovascular reactivity in women.

Methods:The participants were 57 women working in long term care homes. Heart rate variability and systolic arterial pressure variability were used as markers of autonomic function. Organisational justice was measured using the scale of Moorman. Data on other risk factors were also collected.

Results:Results from logistic regression models showed that the risk for increased low frequency band systolic arterial pressure variability was 3.8–5.8 times higher in employees with low justice than in employees with high justice. Low perceived justice was also related to an 80% excess risk of reduced high frequency heart rate variability compared to high perceived justice, but this association was not statistically significant.

Conclusions:These findings are consistent with the hypothesis that cardiac dysregulation is one stress mechanism through which a low perceived justice of decision making procedures and interpersonal treatment increases the risk of health problems in personnel.
A higher risk of congenital anomalies in the offspring of personnel who served aboard a Norwegian missile torpedo boat
Authors: Mageroy N , Mollerlokken O J , Riise T , Koefoed V , Moen B E
Published: January 2006

Background:In the 1990s, congenital anomalies were reported among children whose fathers had served aboard a Norwegian missile torpedo boat (MTB). The Royal Norwegian Navy asked the University of Bergen to look into this problem as one part of a general health and work environment surveillance.

Aims:To estimate any increased risk of having children with congenital anomalies and having stillborn children among the offspring of workers that had served aboard the MTB and to investigate possible differences in exposure and other risk factors between these groups.

Methods:Data from a cross-sectional study among all current employees of the Norwegian Navy (n = 2265, response rate 58%) were analysed.

Results:The prevalence ratio of having a child with congenital malformations associated with working on the ship was 4.0 (95% CI 1.9 to 8.6). The prevalence ratio of having a child who was stillborn or died within one week was 4.1 (95% CI 1.7 to 9.9).

Conclusion:Service aboard the MTB was associated with an increased risk of having children with congenital birth defects and having children that were stillborn. The causes of these findings are unknown.
Airborne occupational exposures and risk of oesophageal and cardia adenocarcinoma
Authors: Jansson C , Plato N , Johansson A L V , Nyrén O , Lagergren J
Published: January 2006

Background:The reasons for the increasing incidence of and strong male predominance in patients with oesophageal and cardia adenocarcinoma remain unclear. The authors hypothesised that airborne occupational exposures in male dominated industries might contribute.

Methods:In a nationwide Swedish population based case control study, 189 and 262 cases of oesophageal and cardia adenocarcinoma respectively, 167 cases of oesophageal squamous cell carcinoma, and 820 frequency matched controls underwent personal interviews. Based on each study participant’s lifetime occupational history the authors assessed cumulative airborne occupational exposure for 10 agents, analysed individually and combined, by a deterministic additive model including probability, frequency, and intensity. Furthermore, occupations and industries of longest duration were analysed. Relative risks were estimated by odds ratios (OR), with 95% confidence intervals (CI), using conditional logistic regression, adjusted for potential confounders.

Results:Tendencies of positive associations were found between high exposure to pesticides and risk of oesophageal (OR 2.3 (95% CI 0.9 to 5.7)) and cardia adenocarcinoma (OR 2.1 (95% CI 1.0 to 4.6)). Among workers highly exposed to particular agents, a tendency of an increased risk of oesophageal squamous cell carcinoma was found. There was a twofold increased risk of oesophageal squamous cell carcinoma among concrete and construction workers (OR 2.2 (95% CI 1.1 to 4.2)) and a nearly fourfold increased risk of cardia adenocarcinoma among workers within the motor vehicle industry (OR 3.9 (95% CI 1.5 to 10.4)). An increased risk of oesophageal squamous cell carcinoma (OR 3.9 (95% CI 1.2 to 12.5)), and a tendency of an increased risk of cardia adenocarcinoma (OR 2.8 (95% CI 0.9 to 8.5)), were identified among hotel and restaurant workers.

Conclusions:Specific airborne occupational exposures do not seem to be of major importance in the aetiology of oesophageal or cardia adenocarcinoma and are unlikely to contribute to the increasing incidence or the male predominance.
Household exposure to pesticides and risk of childhood acute leukaemia
Authors: Menegaux F , Baruchel A , Bertrand Y , Lescoeur B , Leverger G , Nelken B , Sommelet D , Hémon D , Clavel J
Published: January 2006

Objectives:To investigate the relation between childhood acute leukaemia and household exposure to pesticides.

Methods:The study included 280 incident cases of acute leukaemia and 288 controls frequency matched on gender, age, hospital, and ethnic origin. The data were obtained from standardised face to face interviews of the mothers with detailed questions on parental occupational history, home and garden insecticide use, and insecticidal treatment of pediculosis. Odds ratios were estimated using unconditional regression models including the stratification variables parental socioeconomic status and housing characteristics.

Results:Acute leukaemia was observed to be significantly associated with maternal home insecticide use during pregnancy (OR = 1.8, 95% CI 1.2 to 2.8) and during childhood (OR = 1.7, 95% CI 1.1 to 2.4), with garden insecticide use (OR = 2.4, 95% CI 1.3 to 4.3), and fungicide use (OR = 2.5, 95% CI 1.0 to 6.2) during childhood. Insecticidal shampoo treatment of pediculosis was also associated with childhood acute leukaemia (OR = 1.9, 95% CI 1.2 to 3.3).

Conclusion:The results reported herein support the hypothesis that various types of insecticide exposure may be a risk factor for childhood acute leukaemia. The observed association with insecticidal shampoo treatment of pediculosis, which has never been investigated before, requires further study.
Relationship of fat mass and serum estradiol with lower extremity bone in persons with chronic spinal cord injury
Authors: Bauman William A. , Spungen Ann M. , Wang Jack , Pierson Richard N. , Schwartz Ernest
Published: January 2006

In the spinal cord injury (SCI) population, a relationship between adiposity and leg bone has not been reported, nor one between serum estradiol and leg bone mass. A cross-sectional, comparative study of 10 male pairs of monozygotic twins discordant for SCI was performed. Relationships were determined among bone mineral density (BMD), bone mineral content (BMC), lean mass, fat mass, and serum sex steroids. In the twins with SCI, significant relationships were evident between leg BMD or BMC with total body percent fat ( r2 = 0.49, P < 0.05; r2 = 0.45, P = 0.05), leg fat mass ( r2 = 0.76, P < 0.0005; r2 = 0.69, P = 0.005), and serum estradiol ( r2 = 0.40, P = 0.05; r2 = 0.37, P = 0.05). By stepwise regression analysis, in the twins with SCI, leg fat mass was found to be the single most significant predictor of leg BMD or BMC ( F = 12.01, r2 = 0.76, P = 0.008; F = 50.87, r2 = 0.86, P < 0.0001). In the able-bodied twins, leg lean mass correlated with leg BMD and BMC ( r2 = 0.58, P = 0.01; r2 = 0.87, P = 0.0001). By use of within-pair differences, significant correlations were found for leg lean mass loss with leg BMD loss ( r2 = 0.56, P = 0.01) or leg BMC loss ( r2 = 0.64, P = 0.0005). In conclusion, in twins with SCI, significant correlations were observed between fat mass and leg BMD or BMC as well as between serum estradiol values and leg BMD. The magnitude of the leg muscle mass loss was correlated with the magnitude of bone loss.
Expression of canonical transient receptor potential (TRPC) proteins in human glomerular mesangial cells
Authors: Sours Sherry , Du Juan , Chu Shaoyou , Ding Min , Zhou Xin J. , Ma Rong
Published: January 2006

Mesangial cells are located within glomerular capillary loops and contribute to the physiological regulation of glomerular hemodynamics. The function of mesangial cells is controlled by a variety of ion channels in the plasma membrane, including nonselective cation channels, receptor-operated Ca2+channels, and recently identified store-operated Ca2+channels. Although the significance of these channels has been widely acknowledged, their molecular identities are still unknown. Recently, the members of the canonical transient receptor potential (TRPC) protein family have been demonstrated to behave as cation channels. The present study was performed to identify the isoforms of endogenous TRPC proteins in human mesangial cells (HMCs) and their interactions. Western blotting showed that TRPC1, 3, 4, and 6 were expressed in cultured HMCs. Consistently, immunofluorescent confocal microscopy revealed specific stainings for TRPC1, 3, 4, and 6 with predominant intracellular localization. However, TRPC5 and 7 were not detectable at protein level by either Western blotting or immunofluorescent staining. The expression of TRPC1, 3, 4, and 6 was also observed in rat and human glomeruli using fluorescent immunohistochemistry. Furthermore, coimmunoprecipitation experiments and immunofluorescent double staining displayed that TRPC1 had physical interaction with TRPC4 and 6, while no interactions were detected among other isoforms of TRPCs. Ca2+fluorescent ratiometry measurement showed that store-operated Ca2+entry in HMCs was significantly reduced by knocking down TRPC1, but enhanced by overexpressing TRPC1. These results suggest that HMCs specifically express isoforms of TRPC1, 3, 4, and 6 proteins. These isoforms of TRPCs might selectively assemble to form functional complexes.
A1adenosine receptor knockout mice are protected against acute radiocontrast nephropathy in vivo
Authors: Lee H. Thomas , Jan Michael , Bae Soo Chan , Joo Jin Deok , Goubaeva Farida R. , Yang Jay , Kim Mihwa
Published: January 2006

The role of renal A1adenosine receptors (A1AR) in the pathogenesis of radiocontrast nephropathy is controversial. We aimed to further elucidate the role of A1AR in the pathogenesis of radiocontrast nephropathy and determine whether renal proximal tubule A1AR contribute to the radiocontrast nephropathy. To induce radiocontrast nephropathy, A1AR wild-type (WT) or knockout (KO) mice were injected with a nonionic radiocontrast (iohexol, 1.5–3 g iodine/kg). Some A1WT mice were pretreated with 8-cyclopentyl-1,3-dipropylxanthine (DPCPX; a selective A1AR antagonist) before iohexol injection. A1AR contribute to the pathogenesis of radiocontrast nephropathy in vivo as the A1WT mice developed significantly worse acute renal failure, more renal cortex vacuolization, and had lower survival 24 h after iohexol treatment compared with the A1KO mice. DPCPX pretreatment also protected the A1WT mice against radiocontrast-induced acute renal failure. No differences in renal cortical apoptosis or inflammation were observed between A1WT and A1KO mice. To determine whether the proximal tubular A1AR mediate the direct renal cytotoxicity of radiocontrast, we treated proximal tubules in culture with iohexol with or without 2-chloro- N6-cyclopentyladenosine (a selective A1AR agonist) or DPCPX pretreatment. We also subjected cultured proximal tubule cells overexpressing A1AR or lacking A1AR to radiocontrast injury. Iohexol caused a direct dose-dependent reduction in proximal tubule cell viability as well as proliferation. Neither the A1AR agonist nor the antagonist treatment affected proximal tubule viability or proliferation. Moreover, overexpression or lack of A1AR failed to impact the iohexol toxicity on proximal tubule cells. Therefore, we conclude that radiocontrast causes acute renal failure via mechanisms dependent on A1AR; however, renal proximal tubule A1AR do not contribute to the direct tubular toxicity of radiocontrast.