bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling, Analysis, and Optimal Design of the Automotive Transmission Ball Capsule System
Authors: Song Xingyong , Zulkefli Mohd Azrin Mohd , Sun Zongxuan , Miao Hsu-Chiang
Published: February 2010

Clutch shift control is critical for the performance and fuel economy of automotive transmissions, including both automatic and hybrid transmissions. Among all the factors that influence clutch shift control, clutch fill and clutch engagement are crucial to realize a fast and smooth clutch shift. When the clutch is not engaged, the fluid held by the centrifugal force inside of the clutch chamber, which introduces additional pressure that will affect the subsequent clutch fill and engagement processes, should be released. To realize this function, a ball capsule system is introduced and mounted on the clutch chamber. When the clutch chamber is ready to be filled for engagement, the ball capsule needs to close quickly and remain closed until the clutch is disengaged. It is also desirable to have an appropriate closing velocity for the ball capsule to minimize noise and wear. In this paper, the ball capsule dynamics is modeled, in which the derivation of the ball capsule throttling area is considered novel and critical because of its asymmetrical nature. Through this, the ball capsule’s intrinsic positive feedback structure is also revealed, which is considered to be the key to realize a fast response. Moreover, through the system dynamics analysis, the slope angle of the capsule is found to be an effective control parameter for system performance and robustness. To this end, the optimal shape of the capsule is designed using dynamic programming to achieve the desired performance.
Influence of Ring Gear Rim Thickness on Planetary Gear Set Behavior
Authors: Kahraman A. , Ligata H. , Singh A.
Published: February 2010

In this study, results of an experimental and theoretical study on the influence of rim thickness of the ring gear on rim deflections and stresses and planet load sharing of a planetary gear set are presented. The experimental study consists of measurement of ring gear deflections and strains for gear sets having various numbers of planets, different ring gear rim thicknesses, as well as various carrier pinhole position errors. Root and hoop strain gauges and displacement probes are placed at various locations so that the variations due to external splines of the stationary ring gear can also be quantified. A family of quasistatic deformable-body models of the test planetary gear sets is developed to simulate the experiments. The predictions and measurements are compared with the assessment of the accuracy of the models within wide ranges of parameters. The influence of rim thickness on ring gear stresses and deflections and planet load sharing are quantified together with the interactions between the rim flexibility and the spline conditions. The results from this study confirm that the ring gear deflections and the ring gear support conditions must be included in the design process as one of the major factors.
Mechanical Engineering Design Complexity Metrics: Size, Coupling, and Solvability
Authors: Summers Joshua D. , Shah Jami J.
Published: February 2010

Developing objective measures for evaluating and measuring the complexity of design would facilitate (1) empirical studies that require the use of equivalent but different design problems, (2) the development of design curriculums, and (3) the comparison of computer aided design automation tools. This paper surveys and evaluates different approaches to defining complexity in design for the design problem, process, and product. Three fundamental aspects to complexity are identified, size, coupling, and solvability, and expanded with respect to the three elements of design, problem, process, and product. Alternative methods for measuring these characteristics of the design are based on computational, information, and traditional design views of complexity. A method of measuring size as it relates to complexity is proposed for measuring the information content of design. A second method is proposed for decomposing a graph-based representation of design that provides a measure of the interconnectedness as it relates to complexity. Finally, two methods are proposed for determining the solvability complexity of design based on the effort involved and the degree of freedom of design. These measures are developed specifically for parametric and geometric problems as found in the embodiment design, but these principles may be applied beyond this.
Reliability-Based Optimal Design and Tolerancing for Multibody Systems Using Explicit Design Space Decomposition
Authors: Arenbeck Henry , Missoum Samy , Basudhar Anirban , Nikravesh Parviz
Published: February 2010

This paper introduces a new approach for the optimal geometric design and tolerancing of multibody systems. The approach optimizes both the nominal system dimensions and the associated tolerances by solving a reliability-based design optimization (RDBO) problem under the assumption of truncated normal distributions of the geometric properties. The solution is obtained by first constructing the explicit boundaries of the failure regions (limit state function) using a support vector machine, combined with adaptive sampling and uniform design of experiments. The use of explicit boundaries enables the treatment of systems with discontinuous or binary behaviors. The explicit boundaries also allow for an efficient calculation of the probability of failure using importance sampling. The probability of failure is subsequently approximated over the whole design space (the nominal system dimensions and the associated tolerances), thus making the solution of the RBDO problem straightforward. The proposed approach is applied to the optimization of a web cutter mechanism.
A QFT Framework for Antiwindup Control Systems Design
Authors: Moreno J. C. , Baños A. , Berenguel M.
Published: February 2010

The paper is devoted to the robust stability problem of linear time invariant feedback control systems with actuator saturation, especially in those cases with potentially large parametric uncertainty. The main motivation of the work has been twofold: First, most of the existing robust antiwindup techniques use a conservative plant uncertainty description, and second, previous quantitative feedback theory (QFT) results for control systems with actuator saturation are not suitable to achieve robust stability specifications when the control system is saturated. Traditionally, in the literature, this type of problems has been solved in terms of linear matrix inequalities (LMIs), using less structured uncertainty descriptions as given by the QFT templates. The problem is formulated for single input single output systems in an input-output (I/O) stability sense, and is approached by using a generic three degrees of freedom control structure. In this work, a QFT-based design method is proposed in order to solve the robust stability problem of antiwindup design methods. The main limitation is that the plant has poles in the closed left half plane, and at most, has one integrator. The work investigates robust adaptations of the Zames–Falb stability multipliers result, and it may be generalized to any compensation scheme that admits a decomposition as a feedback interconnection of linear and nonlinear blocks (Lur’e type system), being antiwindup systems as a particular case. In addition, an example will be shown, making explicit the advantages of the proposed method in relation to previous approaches.
Differentially Flat Designs of Underactuated Mobile Manipulators
Authors: Ryu Ji-Chul , Sangwan Vivek , Agrawal Sunil K.
Published: February 2010

This paper presents a methodology for design of mobile vehicles, mounted with underactuated manipulators operating in a horizontal plane, such that the combined system is differentially flat. A challenging question of how to perform point-to-point motions in the state space of such a highly nonlinear system, in spite of the absence of some actuators in the arm, is answered in this paper. We show that, by appropriate inertia distribution of the links and addition of torsion springs at the joints, a range of underactuated designs is possible, where the underactuated mobile manipulator system is differentially flat. The differential flatness property allows one to efficiently solve the problem of trajectory planning and feedback controller design for point-to-point motions in the state space. The proposed method is illustrated by the example of a mobile vehicle with an underactuated three-link manipulator.
A Dynamic Model of an Electropneumatic Valve Actuator for Internal Combustion Engines
Authors: Ma Jia , Zhu Guoming G. , Schock Harold
Published: February 2010

This paper presents a detailed model of a novel electropneumatic valve actuator for both engine intake and exhaust valves. The valve actuator’s main function is to provide variable valve timing and variable lift capabilities in an internal combustion engine. The pneumatic actuation is used to open the valve and the hydraulic latch mechanism is used to hold the valve open and to reduce valve seating velocity. This combination of pneumatic and hydraulic mechanisms allows the system to operate under low pressure with an energy saving mode. It extracts the full pneumatic energy to open the valve and use the hydraulic latch that consumes almost no energy to hold the valve open. A system dynamics analysis is provided and followed by mathematical modeling. This dynamic model is based on Newton’s law, mass conservation, and thermodynamic principles. The air compressibility and liquid compressibility in the hydraulic latch are modeled, and the discontinuous nonlinearity of the compressible flow due to choking is carefully considered. Provision is made for the nonlinear motion of the mechanical components due to the physical constraints. Validation experiments were performed on a Ford 4.6 l four-valve V8 engine head with different air supply pressures and different solenoid pulse inputs. The simulation responses agreed with the experimental results at different engine speeds and supply air pressures.
Modified Maximum Entropy Fuzzy Data Association Filter
Authors: Tafti Abdolreza Dehghani , Sadati Nasser
Published: February 2010

The problem of fuzzy data association for target tracking in a cluttered environment is discussed in this paper. In data association filters based on fuzzy clustering, the association probabilities of tracking filters are reconstructed by utilizing the fuzzy membership degree of the measurement belonging to the target. Clearly in these filters, the fuzzy clustering method has an important role; better approach causes better precision in target tracking. Recently, by using the information theory, the maximum entropy fuzzy data association filter (MEF-DAF), as a fast and efficient algorithm, is introduced in literature. In this paper, by modification of a fuzzy clustering objective function, which is prepared for using in target tracking, a modified maximum entropy fuzzy data association filter (MMEF-DAF) is proposed. The MMEF-DAF has a better performance in case of single and multiple target tracking than MEF-DAF, and the other known algorithms such as probabilistic data association filter and the hybrid fuzzy data association filter. Using Monte Carlo simulations, the superiority of the proposed algorithm in comparison with the previous ones is demonstrated. Simply, less computational cost and suitability for real-time applications are the main advantages of the proposed algorithm.
Online Identification and Stochastic Control for Autonomous Internal Combustion Engines
Authors: Malikopoulos Andreas A. , Papalambros Panos Y. , Assanis Dennis N.
Published: February 2010

Advanced internal combustion engine technologies have afforded an increase in the number of controllable variables and the ability to optimize engine operation. Values for these variables are determined during engine calibration by means of a tabular static correlation between the controllable variables and the corresponding steady-state engine operating points to achieve desirable engine performance, for example, in fuel economy, pollutant emissions, and engine acceleration. In engine use, table values are interpolated to match actual operating points. State-of-the-art calibration methods cannot guarantee continuously the optimal engine operation for the entire operating domain, especially in transient cases encountered in the driving styles of different drivers. This article presents brief theory and algorithmic implementation that make the engine an autonomous intelligent system capable of learning the required values of controllable variables in real time while operating a vehicle. The engine controller progressively perceives the driver’s driving style and eventually learns to operate in a manner that optimizes specified performance criteria. A gasoline engine model, which learns to optimize fuel economy with respect to spark ignition timing, demonstrates the approach.
Consideration of Demographics and Variance in Regression Approaches to Estimating Body Dimensions for Spatial Analysis of Design
Authors: Nadadur Gopal , Parkinson Matthew B.
Published: February 2010

A common objective in designing for human variability is to consider the variability in body size and shape of the target user population. Since anthropometric data specific to the user population of interest are seldom available, the variability is approximated. This is done in a number of ways, including the use of data from populations that are well-documented (e.g., the military), proportionality constants, and digital human models. These approaches have specific limitations, including a failure to consider the effects of lifestyle and demography, resulting in products, tasks, and environments that are inappropriately sized for the actual user population, causing problems with safety, fit, and performance. This paper explores a regression-based approach in a context where the demographic distributions of descriptors (e.g., race/ethnicity, age, and fitness) are dissimilar for the database and target population. Also examined is a stratified regression model involving the development of independent anthropometry-estimation models for each racial group. When using regression with residual variance, stratification on the predictor demographics to obtain estimates of gender, stature, and BMI distributions is shown to be sufficiently robust for usual database-target population combinations. Consideration of demographic variables in development of the regression model provides marginal improvement, but could be appropriate in specific situations.
Unified Approach to Cycloid Drive Profile, Stress, and Efficiency Optimization
Authors: Sensinger Jonathon W.
Published: February 2010

Cycloid drives are compact, efficient speed reducers. In this paper, a unified set of equations is presented to optimize their design. The conceptual framework and profile design are described. Sources and effects of tolerance are then introduced, including profile reduction, backlash and torque ripple, and maximum gear-ratio. Equations for stress, efficiency, and moment of inertia are provided.
An Enhanced CMM Model for the Accurate Prediction of Steady-State Performance of CVT Chain Drives
Authors: Carbone G. , De Novellis L. , Commissaris G. , Steinbuch M.
Published: February 2010

The paper deals with the theoretical and experimental evaluation of the performance of a continuously variable transmission chain drive in steady-state conditions. We propose an enhanced version of the Carbone–Mangialardi–Mantriota (CMM) model, to accurately predict the slip behavior and the traction performance of the variator. To achieve this objective, it is necessary to accurately estimate the elastic displacements of the pulley. The determination of the actual pulley deformation allows to obtain a better estimation of the sliding velocities between the pins and the pulley surfaces and, therefore, to calculate the amount of total slip between the primary and secondary pulleys with a higher degree of accuracy. In contrast to multibody models, the approach presented here has a very simple formulation and results in an easy implementation, which allows a complete and fast evaluation of the variator working points. The theoretical results are discussed and critically compared with experimental data. The comparison confirms the validity of the CMM approach in a large range of clamping forces, speed ratios and torque loads.
Mathematical Modeling and Simulation of the External and Internal Double Circular-Arc Spiral Bevel Gears for the Nutation Drive
Authors: Yao Ligang , Gu Bing , Haung Shujuan , Wei Guowu , Dai Jian S.
Published: February 2010

The purpose of this paper is to propose a pair of external and internal spiral bevel gears with double circular-arc in the nutation drive. Based on the movement of nutation, this paper develops equations of the tooth profiles for the gear set, leading to the mathematical modeling of the spiral bevel gear with a constant helical angle gear alignment curve, enabling the tooth surface to be generated, and permitting the theoretical contacting lines to be produced in light of the meshing function. Simulation and verification are carried out to prove the mathematical equations. Numerical control (NC) simulation of machining the external and internal double circular-arc spiral bevel gears is developed, and the spiral gears were manufactured on a NC milling machine. The prototype of the nutation drive is illustrated in the case study at the end of this paper.
Quantum turbulence at room temperature
Authors: Llaguno C. , Muriel A.
Published: February 2010

The authors explain the multilevel turbulent nitrogen data of a Hinkle pipe experiment at 25 °C using the Muriel molecular theory of turbulence and the quantum rotational energy spectrum of nitrogen. As a result, they generalize the scope of quantum turbulence at superfluid helium temperature to include room temperature turbulence data for nitrogen.
SUMOylation Mediates the Nuclear Translocation and Signaling of the IGF-1 Receptor
Authors: Sehat Bita , Tofigh Ali , Lin Yingbo , Trocmé Eric , Liljedahl Ulrika , Lagergren Jens , Larsson Olle
Published: February 2010

Attachment of SUMO lets insulin-like growth factor receptors act as transcriptional regulators in the nucleus.
Challenging the Gβγ Paradigm
Authors: Gough Nancy R.
Published: February 2010

In the budding yeast
Kluyveromyces lactis
, the β subunit of the G protein can function without the γ subunit in the mating response.
Do Pathogen Sensors Make You Fat?
Authors: Wong Wei
Published: February 2010

A kinase with a role in the detection of RNA-based viruses also responds to metabolic stress.
Glucocorticoid Receptor DNA Binding Decoy Is a Gas
Authors: Garabedian Michael J. , Logan Susan K.
Published: February 2010

By mimicking a DNA response element, a noncoding RNA inhibits glucocorticoid receptor activity.
Synthesis of zirconocene silsesquioxane complexes and their ethene polymerization activity in systems with methylaluminoxane
Authors: Varga Vojtech , Pinkas Jiří , Gyepes Róbert , Štěpnička Petr , Horáček Michal , Bastl Zdeněk , Mach Karel
Published: February 2010

Protocols for obtaining defined zirconocene complexes with polyhedral oligomeric silsesquioxanes with mono-, di-, and trisilanol functionality (SIPOSS, DIPOSS, and TRIPOSS) were established. The TRIPOSS silanolates binding one zirconocene and one chlorozirconocene moiety, [{(c-C5H9)7Si7O9O3}Zr2Cl(η5-C5H4R)4] (1, R = Bu; 2, R = H), were obtained by reacting the silanol with the respective zirconocene dichloride and triethylamine in CH2Cl2 in a 1.0:3.0:3.0 molar ratio, an excess of the zirconocene dichloride being required to suppress intramolecular dehydration of TRIPOSS. The related SIPOSS complex, [{(c-C5H9)7Si8O12O}2Zr(η5-C5H4Bu)2] (3), was prepared similarly at the stoichiometric ratio of [ZrCl2(η5-C5H4Bu)2]/ SIPOSS/NEt3 equal to 1.0:2.0:2.0. When employed in the 1.0:1.0:1.0 ratio, the same reagents afforded only the impure complex [{(c-C5H9)7Si8O12O}ZrCl(η5-C5H4Bu)2] (4), contaminated with 3 and unreacted [ZrCl2(η5-C5H4Bu)2]. Finally, the zirconocene complexes with SIPOSS and DIPOSS moiety, [{(c-C5H9)7Si8O12O}2Zr(η5-C5H5)2] (5) and [(c-C5H9)7Si7O9(OSiMe3)O2}- Zr(η5-C5H5)2] (6), respectively, were obtained by reacting [ZrMe2(η5-C5H5)2] with stoichiometric amounts of the appropriate silanols. All complexes were characterized by 1H, 13C, 29Si NMR and IR spectra, and by elemental analysis from XPS spectra. Preliminary ethene polymerization experiments showed that compounds 5 or 6 when combined with an excess of methylaluminoxane were nearly as active as [ZrCl2(η5-C5H5)2] whereas compound 2 was by about one order of magnitude less active.
Systemic inflammatory response syndrome in diseases of the skin
Authors: Thomas Molly , Peter John Victor , Williams Abhilasha , Job Victoria , George Renu
Published: February 2010

Background

A number of dermatological conditions present with features of systemic inflammatory response syndrome (SIRS). This study evaluated the incidence and outcome of SIRS in patients with dermatological diseases.

Study design

Prospective cohort study.

Results

Patients admitted to a university hospital with a skin disease and fulfilling at least two SIRS criteria were included. The primary outcome measure was mortality. Secondary outcomes included incidence of multiple organ dysfunction syndrome (MODS), sepsis, severe sepsis and shock. Over 14 months, 2765 inpatients with skin related problems were examined. These included 721 patients admitted directly to the dermatology ward and 2044 patients referred from other departments within the hospital, with cutaneous manifestations. The incidence of SIRS in this cohort was 2.4% (n=67). The mean (SD) age was 32.6 (19.7) years with a male:female ratio of 1.2:1. Cutaneous adverse drug reaction (CADR) was the most common cause of SIRS (35.8%). During hospitalisation, 37 patients (55.2%) developed sepsis, 23 (34.4%) MODS, 15 (22.4%) severe sepsis and 6 (9%) shock. Methicillin sensitive Staphylococcus aureus was the most common skin isolate (41.4%) and Enterococcus the most common blood isolate. Overall mortality was 15% (10/67). Older age, low albumin, MODS, severe sepsis and shock were associated with an increased risk of death (p<0.03). Positive blood cultures, liver or lung involvement were also significantly associated with increased mortality (p<0.01).

Conclusion

The incidence of SIRS was low in dermatological diseases. In this cohort, CADR was the most common cause of SIRS. Patients who developed sepsis or MODS had a poor outcome.
Does the timing of comorbidity affect colorectal cancer survival? A population based study
Authors: Shack Lorraine G , Rachet Bernard , Williams Evelyn M I , Northover John M A , Coleman Michel P
Published: February 2010

Objectives

Comorbid conditions in colorectal cancer patients can influence both clinical eligibility for treatment and survival. We aimed to evaluate the effect of comorbidity on 1 year survival from colorectal cancer, and to assess whether this effect varied with the timing of the comorbidity in relation to the cancer diagnosis.

Study design and setting

A population based cohort of 29 563 colorectal cancer patients diagnosed between 1997 and 2004 in the North West of England was evaluated. The excess hazard of death up to 1 year after diagnosis was estimated using deprivation and region specific life tables to adjust for background mortality. Results were adjusted for age and stage at diagnosis.

Results

Comorbid conditions diagnosed during the period 18 to 6 months before the diagnosis of colorectal cancer were strongly associated with lower survival at 1 year. Stage and age remained the strongest predictors of cancer related mortality even after adjustment for comorbidity.

Conclusions

Administrative data provide a good estimate of the prevalence of most comorbid conditions but may be biased for some comorbid conditions that can be contra-indicators for cancer treatment. The time window in which a comorbid condition occurs in relation to the cancer diagnosis should be taken into account. Adjustment should be carried out, where possible, to provide more robust and clinically appropriate comparisons of population based cancer patient survival.
Early dietary exposures and feeding practices: role in pathogenesis and prevention of allergic disease?
Authors: Jennings S , Prescott S L
Published: February 2010

Immune dysregulation has become a hallmark of the modern era. This has led to an epidemic of disease states that result from failed immune surveillance and inappropriate or maladaptive immune responses to self-antigens (autoimmunity) and environmental antigens (allergy). Although environmental change is clearly implicated, the specific causes are still unconfirmed. Any hope to reverse such immune dysfunction must be based on a clearer understanding of the causal pathways and the environmental factors that may be driving the concerning surge in disease rates. This review explores the role of modern dietary changes that, through their known documented immune effects, may play a role in either promoting or preventing disease. Food allergen avoidance has been largely unsuccessful, and most expert bodies no longer recommend delayed complementary feeding or the avoidance of any specific allergenic foods, unless symptoms develop and allergy is confirmed. Rather, focus has shifted to other factors that may influence the ability to develop immune tolerance. There is now evidence that specific nutrients, such as folate, have the capacity to promote an allergic phenotype by epigenetically altering gene expression during early development. A number of other dietary factors including n-3 polyunsaturated fatty acids, oligosaccharides, probiotics, vitamin D, retinoic acid and other antioxidants may also clearly influence immune function and immune development. This review summarises the current evidence, recommendations and future directions in the context of allergy, with the aim of highlighting the need to further investigate the role of diet and nutrition in disease pathogenesis and prevention.
Survey of major complications of intercostal chest drain insertion in the UK
Authors: Harris Ann , O’Driscoll B Ronan , Turkington Peter M
Published: February 2010

Background

Following reports from the National Patient Safety Agency of deaths and serious harm from intercostal chest drains (ICD) we conducted a national survey among chest physicians of their experience of harm associated with ICD.

Methods

A questionnaire was sent to 198 UK chest physicians at 148 acute hospital trusts, enquiring about current practice and any adverse incidents related to chest drains from 2003 to 2008.

Results

101 of 148 trusts (68%) replied. 67 trusts reported at least one major incident involving ICD insertion. 31 Cases of ICD misplacement were reported with seven deaths. Misplaced drains were inserted in liver (10), peritoneal space (6), heart (5), spleen (5), subclavian vessels (2), colon (1), oesophagus (1) and inferior vena cava (1). 47 cases of serious lung or chest wall injuries with eight deaths and six cases of ICD placement on the wrong side with two deaths were reported. The guidewire was lost in the pleural cavity in three cases. 22 of 101 trusts required written patient consent before ICD insertion. 11 trusts had a training policy. 16 trusts had patient information literature for this procedure. The seniority of doctors permitted to insert ICDs was as follows: 30% any doctor; 27% at least 1 year post qualification; 32% at least 2 years, 11% at least 4 years.

Conclusions

67% of responding trusts had encountered major complications of ICD. The survey raised concerns about training and consent. The National Patient Safety Agency has made recommendations to address these risks which are also addressed in the 2009 update of the British Thoracic Society Pleural Disease Guideline.
Role of implantable cardioverter defibrillators in non-ischaemic dilated cardiomyopathy
Authors: Scott Paul A , Roberts Paul R
Published: February 2010

Patients with non-ischaemic dilated cardiomyopathy (NICM) are at significant risk of sudden cardiac death. Multiple randomised trials have shown that implantable cardioverter defibrillators (ICDs) reduce mortality in high-risk patients with NICM. However, despite this, the National Institute for Health and Clinical Excellence specifically excluded patients with NICM from its updated guidance concerning ICD use. This lack of guidance poses clear problems for both clinicians managing patients with NICM and those who commission healthcare services. This review aims to help guide clinicians in this difficult, high-cost and high-risk area.
Endobronchial ultrasound guided transbronchial needle aspiration
Authors: Medford A R L , Bennett J A , Free C M , Agrawal S
Published: February 2010

Staging for non-small cell lung cancer (NSCLC) requires accurate assessment of the mediastinal lymph nodes which determines treatment and outcome. As radiological staging is limited by its specificity and sensitivity, it is necessary to sample the mediastinal nodes. Traditionally, mediastinoscopy has been used for evaluation of the mediastinum especially when radical treatment is contemplated, although conventional transbronchial needle aspiration (TBNA) has also been used in other situations for staging and diagnostic purposes. Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) offers a minimally invasive alternative to mediastinoscopy with additional access to the hilar nodes, a better safety profile, and it removes the costs and hazards of theatre time and general anaesthesia with comparable sensitivity, although the negative predictive value of mediastinoscopy (and sample size) is greater. EBUS-TBNA also obtains larger samples than conventional TBNA, has superior performance and theoretically is safer, allowing real-time sampling under direct vision. It can also have predictive value both in sonographic appearance of the nodes and histological characteristics. EBUS-TBNA is therefore indicated for NSCLC staging, diagnosis of lung cancer when there is no endobronchial lesion, and diagnosis of both benign (especially tuberculosis and sarcoidosis) and malignant mediastinal lesions. The procedure is different than for flexible bronchoscopy, takes longer, and requires more training. EBUS-TBNA is more expensive than conventional TBNA but can save costs by reducing the number of more costly mediastinoscopies. Revenue based tariff systems have been slow to reflect the innovation of techniques such as EBUS-TBNA. In the future, endobronchial ultrasound may have applications in airways disease and pulmonary vascular disease.
Diagnostic utility of anti-Ro52 detection in systemic autoimmunity
Authors: Dugar Manish , Cox Sally , Limaye Vidya , Gordon Tom Paul , Roberts-Thomson Peter John
Published: February 2010

Objectives

To determine the prevalence and diagnostic utility of monospecific anti-Ro52 (defined as an immune response against Ro-52 antigen in the absence of reactivity to Ro-60 antigen) reactivity in selected autoimmune diseases.

Study design

Stored diagnostic non-consecutive serum samples obtained from patients with systemic lupus erythematosus (SLE), primary Sjögren’s syndrome (pSS), systemic sclerosis, idiopathic inflammatory myopathies (IIM), rheumatoid arthritis, primary biliary cirrhosis and mixed essential cryoglobulinaemia were analysed by line immunoassay to detect the presence of anti-Ro52 and other autoantibodies.

Results

Monospecific anti-Ro52 reactivity was found in 51 (12.7%) of the 402 samples tested. Anti-Ro52 was the most common serological marker in patients with IIM (35/147, 23.8%) and co-occurred with anti-Jo1 (10/18, 55.6%; p=0.02). The prevalence of anti-Ro52 reactivity was significantly more than anti-Ro60 reactivity in patients with IIM, systemic sclerosis, primary biliary cirrhosis, mixed essential cryoglobulinemia and pSS. The mean signal intensity of anti-Ro52 reactivity was significantly higher in pSS than SLE and associated with rheumatoid factor positivity. The mean signal intensity of anti-Ro52 correlated with anti-Ro60 and anti-La in pSS and SLE.

Conclusions

Monospecific anti-Ro52 reactivity is not disease specific but may be of importance in patients with IIM. Furthermore, as anti-Ro52 reactivity is more prevalent than anti-Ro60 reactivity in certain autoimmune conditions, specific testing for their distinction in clinical practice is recommended.
THE INNARDS OF AN INSTANTON
Authors: TONG DAVID
Published: February 2010

Instantons are composed of partons.
SOLITONS IN TWO-DIMENSIONAL ANTI-DE SITTER SPACE
Authors: TER VELDHUIS TONNIS
Published: February 2010

Soliton solutions in a scalar field theory defined on an AdS1+1 background space-time are investigated. An analytic soliton solution is obtained in a polynomial model, and the classical soliton mass is calculated. The fluctuation spectrum around the soliton solution is determined, and the one-loop quantum correction to the soliton mass is computed in the semi-classical approximation.
QUANTUM STRINGS IN AdS5 × S5 AND GAUGE–STRING DUALITY
Authors: TSEYTLIN A. A.
Published: February 2010

We review some recent progress in understanding the spectrum of energies/dimensions of strings/operators in AdS5 × S5 – planar [Formula: see text] super Yang-Mills correspondence. We consider leading strong coupling corrections to the energy of lightest massive string modes in AdS5 × S5, which should be dual to members of the Konishi operator multiplet in the SYM theory. This determines the general structure of strong-coupling expansion of the anomalous dimension of the Konishi operator. We use 1-loop results for semiclassical string states to extract information about the leading coefficients in this expansion.
CHIRAL SYMMETRY AND HOLOGRAPHIC MODELS OF THE BARYON: TESTING HOLOGRAPHIC MODELS OF THE BARYON WITH MODEL-INDEPENDENT RELATIONS
Authors: COHEN THOMAS D.
Published: February 2010

A model-independent relation for the long-distance behavior of baryon form factors in the large Nc and chiral limits is introduced and used to probe the consistency of various models of the baryon including recently proposed holographic models. This relation is satisfied by the Skyrme model and all other 4D semiclassical chiral soliton models. The "bottom-up" Pomarol-Wulzer holographic model which treats baryons as 5D Skyrmions also satisfies the relation. However, the "top down" holographic model treating baryons as instantons in the Sakai-Sugimoto model fails to satisfy the relation. This failure can ultimately be traced to the imposition of a scale separation in the model between the curvature scale and the KK scale; such a scale separation has no counterpart in QCD.
UNPARTICLE PHYSICS
Authors: GEORGI HOWARD
Published: February 2010

Misha Shifman knows much more about conformal symmetry than I do, but I have been thinking hard about it, and I thought it would be fun to present some of my ideas as a little birthday present.
NATURE OF MICROSCOPIC BLACK HOLES AND GRAVITY IN THEORIES WITH PARTICLE SPECIES
Authors: DVALI GIA
Published: February 2010

Relying solely on unitarity and the consistency with large-distance black hole physics, we derive model-independent properties of the microscopic black holes and of short-distance gravity in theories with N particle species. In this class of theories black holes can be as light as [Formula: see text] and be produced in particle collisions above this energy. We show, that the micro black holes must come in the same variety as the species do, although their label is not associated with any conserved charge measurable at large distances. In contrast with big Schwarzschildian ones, the evaporation of the smallest black holes is maximally undemocratic and is biased in favor of particular species. With an increasing mass the democracy characteristic to the usual macro black holes is gradually regained. The lowest possible mass above which black holes become Einsteinian is [Formula: see text]. This fact uncovers the new fundamental scale (below the quantum gravity scale) above which gravity changes classically, and the properties of black holes and gravity are such as if some extra dimensions open up, although no such input exists in the theory. Our observations indicate that geometry of space may be an emergent concept following from large number of species and the consistency with macro black hole physics. We apply our findings to the phenomenological properties of the micro black holes that can be observed at LHC for large N. Extrapolating our findings to small N, one may ask whether the existence of quark and lepton flavors is already an evidence for emergent extra dimensions at short distances.
MODAL ANALYSIS AND DAMPING MEASUREMENT OF THE HEAD ARM ASSEMBLY OF A SMALL FORM FACTOR HARD DISK DRIVE
Authors: SHI B. J. , GU B. , SHU D. W. , JIN T. H.
Published: February 2010

As non-traditional applications of hard disk drives (HDDs) emerge, the interest in the effects of shock and vibration on small form factor (SFF) drives has come into currency due to the increasingly hostile environments encountered in the usage of the portable computer as well as the application in consumer devices. In this paper, the dynamic characteristics of an SFF drive were investigated using both experimental and numerical techniques, including modal analysis and damping measurement of the head arm assembly (HAA) of the drive. A finite element (FE) model of the HAA was created to perform numerical analysis. The FE model was verified and modified according to numerical results and experimental results. It is found that numerical results of the HAA in it free state and those in its preloading state coincide well with those of experiments, and/or those by other researchers.
FIBER-CONTINUOUS PILLAR-BOARD BIOCOMPOSITE STRUCTURE IN TUMBLEBUG ELYTRA
Authors: CHEN B. , YUAN Q. , FAN J. H. , WANG J. G. , LUO J.
Published: February 2010

The observation of scanning electron microscope (SEM) showed that Tumblebug elytra consist of almost parallel upper and lower cuticles. Both of which are a kind of chitin-fiber-reinforced composite. There is a kind of chitin-fiber-reinforced composite pillars between the upper and lower cuticles, which support and connect the upper and lower cuticles uprightly. More careful observation showed that the chitin fibers in the pillars smoothly extend to the upper and lower composite cuticles forming a kind of fiber-continuous pillar-board composite (FCPBC) structure. Based on the observation, two kinds of pillar-board composite structure specimens, respective with continuous and discontinuous glass fibers, were fabricated with molding and felting processes. The rupture strengths of the two kinds of the specimens were tested and compared. It showed that the rupture strength of the specimens of the FCPBC structure is markedly larger than that of the specimens of the fiber-discontinuous pillar-board composite (FDPBC) structure. At last, the experimental result was analyzed for illumining the mechanism of the FCPBC structure in the enhancement of the strength.
SHOCK PULSE AMPLITUDE AND WIDTH EFFECTS ON THE SHOCK RESPONSE OF AN OPERATIONAL DISK DRIVE
Authors: GU BIN , SHU DONGWEI , SHI BAOJUN
Published: February 2010

The interest in the effects of shock on HDDs has come into currency due to the reduction of the flying height of the head/disk interface and the increasingly hostile environments encountered in the usage of many consumer electronics and portable devices. This paper discusses the shock pulse amplitude and width effects on the shock response of an operational disk drive. The drive is subjected to half sine acceleration shock pulse with varying amplitude and width. A finite element model of the hard disk drive is developed in the commercially available finite element package, ANSYS/LSDYNA. The air bearing between the disk and the slider is modeled by nonlinear springs. The contact between the disk and the slider is also considered. It is found that the shock response of the drive is sensitive to both the shock pulse amplitude and width.
CORE-TUBE MORPHOLOGY OF MULTIWALL CARBON NANOTUBES
Authors: SATO MOTOHIRO , SHIMA HIROYUKI , IIBOSHI KOHTAROH
Published: February 2010

The present paper investigates the cross-sectional morphology of Multiwalled Carbon Nanotubes (MWNTs) restrained radially and circumferentially by an infinite surrounding elastic medium, subjected to uniform external hydrostatic pressure. In this study, a two-dimensional plane strain model is developed, assuming no variation of load and deformation along the tube axis. We find some characteristic cross-sectional shapes from the elastic buckling analysis. The effect of the surrounded elastic medium on the cross-sectional shape which occurs due to pressure buckling is focused on by the comparison with the shape for no elastic medium case in our discussion. It is suggested that in no embedded elastic medium cases, the cross-sectional shapes of inner tubes maintain circle or oval; on the other hand, an embedded medium may cause inner tube corrugation modes especially when the number of shells for MWNTs is small.
VOID GROWTH AND INTERACTION IN A SOFT MATERIAL
Authors: WONG W. H. , GUO T. F. , CHENG L.
Published: February 2010

Void growth and interaction in a soft material is explored numerically in this work in a three-dimensional context. Discrete initially spherical voids are explicitly modeled ahead of a crack front under small-scale yielding. While a multiple void interaction mechanism can be identified in our study, computations show a qualitatively similar void growth exhibited for the initial void volume fractions considered, f0 = 0.1% and 1%. Extensive void growth in the damage process zone are observed upon application of load, with the resultant deformed voids taking on a prolated void shape. A micromechanical analysis of void growth is also carried out and the numerical results suggest a failure mechanism in the soft material not attributed to void coalescence but by a mechanism analogous to tearing.
Anion Effect of Zinc Source on Chemically Deposited ZnS(O,OH) Films
Authors: Ernits K. , Muska K. , Danilson M. , Raudoja J. , Varema T. , Volobujeva O. , Altosaar M.
Published: February 2010

The study on the anion effect of different Zn sources—Zn, ZnCl2, ZnI2, Zn and ZnSO4—on the chemical deposition of ZnS(O,OH) films revealed that the growth rate and composition of the ZnS(O,OH) layer depend on the instability constant (pK) value of the corresponding Zn‐complex Zn(L) n in the chemical bath solution. In the region of pKZn(NH3)2+ > pKZn(L)n the ZnS(O,OH) film′s growth rate and ZnS concentration in films increased with the increasing pK value of the used Zn salt complex up to the pK value of the complex and decreased in the region where pKZn(NH3)2+ < pKZn(L)n. The band gap values (around 3.6 eV in most cases) of deposited ZnS(O,OH) films did not depend on the Zn precursor′s instability constant, the ZnS(O,OH) film from zinc nitrate containing bath has higher band gap energy (Eg = 3.8 eV). The maximum efficiency of CISSe and CZTSSe monograin layer solar cells was gained with ZnS(O,OH) buffer layer deposited from CBD solution containing Zn as Zn source, which provided the highest growth rate and ZnS concentration in the ZnS(O,OH) film on glass substrates.
Delayed Presentation of a Giant Ascending Aortic Aneurysm following Aortic Valve Replacement
Authors: Göncü Tugrul , Sezen Mustafa , Ari Hasan , Tiryakioglu Osman , Yumun Gündüz , Yavuz Senol
Published: February 2010

Giant ascending aortic aneurysm formation following aortic valve replacement is rare. A 28-year-old man who underwent aortic valve replacement with a prosthetic valve for aortic regurgitation secondary to congenital bicuspid aortic valve about 10 years ago was diagnosed with a giant ascending aortic aneurysm about 16 cm in diameter in follow-up. The aneurysm was resected leaving the functional old mechanical prosthesis in place and implanted a 34-mm Hemashield woven graft, associated with the left and right coronary artery button implantation. Histological findings of the aortic aneurysm wall showed cystic medial necrosis. The postoperative course was uneventful and postoperative examination demonstrated good surgical results.
Impact of Scoring Single or Multiple Occlusal Lesions on Estimates of Diagnostic Accuracy of the Visual ICDAS-II System
Authors: Jablonski-Momeni Anahita , Ricketts David N. J. , Heinzel-Gutenbrunner Monika , Stoll Richard , Stachniss Vitus , Pieper Klaus
Published: February 2010

Carious lesions can occur at different sites on the occlusal surfaces of teeth and may differ in appearance and severity. This study aimed to evaluate how estimates of reproducibility and accuracy of ICDAS-II were affected when all lesions on occlusal surfaces, or only a representative lesion, were scored. 100 permanent teeth with 1–4 investigation sites on the occlusal surface were examined visually by four examiners. Serial sections of the teeth were assessed for lesion depth. Intra- and interexaminer reproducibility (weighted kappa values), sensitivity, and specificity were calculated for all investigation sites and for a randomly selected site per tooth. Comparing the kappa values for the whole sample and the independent sites, no effect or only a small effect was found. Comparing the areas under the ROC-curves no effect could be shown. Examining multiple sites on teeth leads to results comparable to when a single independent site is chosen per tooth.
Epidemiology of HPV in HIV-Positive and HIV-Negative Fertile Women in Cameroon, West Africa
Authors: Desruisseau Andrew J. , Schmidt-Grimminger Delf , Welty Edith
Published: February 2010

Background. HPV types vary by country and HIV status. There are no data on the prevalent HPV genotypes from Cameroon.Methods. We conducted a cross-sectional, observational study on 65 Cameroonian women. Samples were sent for HPV genotyping and Thin Prep analyses.Results. 41 out of 61 samples tested (67.2%) had HPV subtypes detected. The most common high risk types encountered were: 45 (24.6%) and 58 (21.5%). HIV-positive women were more likely to test positive for any HPV (P=.014), have more than one HPV subtype (P=.003), and to test positive for the high risk subtypes (P=.007). Of those with high risk HPV, HIV-positive women were more likely to have Thin Prep abnormalities than HIV-negative women (P=.013).Conclusions. Oncogenic HPV subtypes 45 and 58 were more prevalent than those subtypes carried in the quadrivalent vaccine. Further studies are needed to assess whether the current vaccine will be effective in this region.
Electronically Tunable Dual‐Input Integrator Employing a Single CDBA and a Multiplier: Voltage Controlled Quadrature Oscillator Design
Authors: Nandi R. , Kar Mousiki , Das Sagarika
Published: February 2010

A new dual‐input differential input active integrator using a current differencing buffered amplifier (CDBA) is proposed. A multiplier element is appropriately used in the circuit whose control voltage (Vc) tunes the integrator time constant (τ) electronically. The design of a voltage controlled quadrature oscillator (VCQO) based on the proposed integrator had been satisfactorily implemented. A new type of measurement for the tuning error of the oscillator based on the Nyquist plot is presented that shows an error of only 2% atfo≈ 1 MHz with Total Harmonic Distortion (THD) less than 3%.
On the Nusselt Solution of a Nonisothermal Two‐Fluid Inclined Film Flow
Authors: Socolowsky Jürgen
Published: February 2010

Nonisothermal viscous two‐fluid flows occur in numerous kinds of coating devices. The corresponding mathematical models often represent two‐dimensional free boundary
value problems for the Navier‐Stokes equations or their modifications. In the present paper we
are concerned with a particular problem of coupled heat and mass transfer. Marangoni convection
is incorporated, too. The solvability of a corresponding stationary problem is discussed. The
obtained results generalize previous results for a similar isothermal problem.