bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of the supplier selection model—a case study in the advanced technology industry
Authors: Chan F T S , Chan H K
Published: April 2011

Because of the pressure of globalization in the last two decades, outsourcing activities has become an important strategic decision so that supplier selection is a prime concern. In fact, the selection problem is more crucial for the manufacturers of sophisticated semiconductor assembly equipments, as it is a multi-item, multi-person and multi-criterion decision problem. Among the reported literature, the analytic hierarchy process (AHP) has been recognized as an appropriate tool to tackle the said problem. In this paper, a case study is reported to illustrate an innovative model which adopts AHP and quality management system principles in the development of the supplier selection model. The proposed model can provide not only a framework for the organization to select supplier but also capability to deploy the company strategy to suppliers. Added to this, it also has flexibility to respond to the changing needs of the organization due to dynamic business environment. Through an illustration of the proposed model, it is found that the supplier selection problem can be solved in a structural and timely manner.
Machine buffer sizing based on the theory of constraint principles and the tabu search technique
Authors: Apolloni S , Lando M , Savino M
Published: April 2011

In the last few years, firms’ efforts have been directed towards improvement in the manufacturing cycle, lead times reduction and quality assurance, due to the ever-increasing time-to-market and quality requirements. In this context to achieve better results in terms of shop floor scheduling and lead time reduction, many scheduling approaches have been developed, but most of these fall short of achieving good results because they do not identify clearly where and how much inventory should be employed (e.g. Davis proposed a heuristic for determining work in process inventories in a flow line). This paper deals with problems of work-in-progress (WIP) inventory management, describing an approach based on the combinatorial problem related to WIP size and location on the shop floor, which is a function of buffer sizes in each operation of the production process. The proposed model has been tested in an aeronautical firm where a relevant growth in the output rate level has been achieved using four WIP buffers with a total inventory of 50 batches.
Effects of hard turning on the fatigue life of ball bearings
Authors: Jacobson M , Gunnberg F
Published: April 2011

The purpose of this paper is to examine how the fatigue life of ball bearings is affected by hard turning. Two different batches of 6309 deep-groove ball bearings were manufactured. The batches had identical balls, cages, and outer rings. The inner rings were soft machined and heat treated in the same way. The inner rings were subsequently processed in two different ways; one batch was ground and honed and the other was hard turned and honed. The bearings were then assembled, and tests were conducted on test rigs designed for bearings. The purpose of the test was to determine the fatigue life of the bearings by means of the inner ring. Based on the results it can be concluded that hard turning improves the fatigue life of ball bearings.
Numerical investigations of performance optimization using variable guide vanes in a multistage compressor of a 6 MW gas turbine engine
Authors: White N. M. , Tourlidakis A , Elder R. L.
Published: April 2011

There is a common requirement in the process, oil, and gas turbine industries for high performance axial flow compressors operating over a wide range of mass flow rate and rotational speed at high efficiency. The trend has been for greater blade loading (pressure rise per stage) and increased efficiency, which are typically achieved through sophisticated, computational fluid dynamics designs. This can, however, lead to other performance compromises, especially for off-design operation where surge margin becomes an important parameter. The objective of this work was to investigate the possibility of using alternative means to gain performance improvements by the intelligent use of variable geometry, which may permit design objectives to be better achieved. Results are presented for an axial flow compressor of a 6 MW industrial gas turbine engine, where a numerical optimization algorithm has been applied to the problem of obtaining optimum performance at design and off-design steady-state operating conditions.
Experimental study on the damage of a 125 MW steam turbine rotor
Authors: Wang Kun , Shuhong Huang , Yanping Zhang , Jidong Lu
Published: April 2011

A study on the damage of a 125 MW steam turbine rotor was carried out through a series of experiments. The unit was in service from May 1992. After 10 years of operation, the integrity of the rotor was threatened by material deterioration caused by fatigue and creep damage at certain critical locations. In this study, sophisticated thermoplastic finite element analysis (FEA) was employed to establish the transient strain/stress and temperature fields of the rotor during the experiments. Based on the results of the FEA and damage-evaluating model, the life loss of the rotor was evaluated and the residual service life of the rotor calculated. The study concluded that changing the running schedule threatened the safety and reliability of the turbine rotor and would reduce its service life, but five more years of safe operation of the rotor could be guaranteed. Some operational suggestions are also presented in this paper, which help to decrease damage during operation.
Operating characteristics of an air-source heat pump under frosting/defrosting conditions
Authors: He Z , Peng X , Xing Z , Shu P
Published: April 2011

This paper presents an experimental investigation on the behavior of an air-source heat pump operating under frosting/defrosting conditions. Dynamic data of parameters, such as the frost layer thickness, compressor suction/discharge pressures, fin temperature, heating capacity, power consumption, and fan electric current, were acquired during the test. Based on these experimental data, the operating characteristics of the heat pump under frosting/defrosting conditions were analysed, and the influence of frosting/defrosting on the performance and reliability of the heat pump was investigated. It was shown that a critical frost layer thickness existed, below which the heat pump presented no noticeable parameter changes. When the frost layer grew above the critical value, the compressor discharge pressure increased rapidly with a slight decrease in the suction pressure, but the shaft power remained almost unchanged. However, due to the increase in airflow resistance, the airflow rate dropped and the fan electric current increased abruptly, leading to fan performance deterioration and a reduction in the system heating capacity. At 50 per cent nominal airflow rate, the frost layer formed later and grew slower than at the nominal airflow rate. Under defrosting conditions, the suction pressure experienced a large drop, which led to frequent on-off switching of the compressor due to pressures falling beneath the low-level limit. This could be avoided by recirculating a portion of the high pressure gas in the compressor receiver back to the compressor inlet through a pipe fitted with a solenoid valve controller.
Influence of taper, Reynolds number and Mach number on the secondary flow field of a highly loaded turbine cascade
Authors: Duden A , Fottner L
Published: April 2011

The meridional divergence of low-pressure turbines has a strong influence on their secondary flow field. This paper describes experimental and numerical investigations on two highly loaded linear turbine cascades with the same blade profile and stacking but with parallel end walls and divergently tapered end walls respectively. The effects of taper, Reynolds number (1.2 × 105, 5 × 105) and Mach number (0.30, 0.59, 0.80) are discussed. Data were obtained using pneumatic probes, pressure tappings and surface flow visualizations. Calculations were performed with the three-dimensional Navier—Stokes solver BTOB3D. The investigations show a strong influence of the taper on the pressure distribution and an unexpected high rise in secondary loss. In both cascades the secondary loss coefficient rises with reduced Reynolds number and Mach number respectively.
Evaluation of implicit numerical methods for building energy simulation
Authors: Crowley M E , Hashmi M S J
Published: April 2011

The stability of numerical methods used for finite difference thermal modelling of buildings is discussed. A known instability in a commonly used process is described and alternative numerical methods with suitable stability properties are identified. With a view to selecting the optimum numerical method, the building energy simulation problem is characterized mathematically and appropriate implicit solvers are compared on the basis of accuracy and computational effort using a building-related test problem prepared for this purpose. A recently developed numerical method with the necessary strong stability is found to possess higher computational efficiency than methods frequently used in this application and it is recommended for inclusion in building energy simulation software.
Qualitative research meets the ghost of Pythagoras
Authors: Michell Joel
Published: April 2011

The issue of qualitative versus quantitative methods is rooted first and foremost in the character of the phenomena investigated and not in an investigator’s methodological preferences. If the phenomenon under investigation is non-quantitative, then it cannot be studied successfully by attempting to use quantitative methods because trying to impose quantitative concepts upon qualitative phenomena misrepresents them. If the target articles provide any guide, these truths are ignored as much by psychologists wanting to mix quantitative with qualitative methods as by mainstream quantitative researchers. These articles display both the power of the modernist fantasy that measurement is always a discretionary choice of any investigator and the power of the persistent delusion that psychological attributes must be measurable. In psychology, as ever, the ghost of Pythagoras rules.
Using numerical data in explicitly interpretive, contextual inquiry: A “practical discourse” framework and examples from Engeström’s research on activity systems
Authors: Yanchar Stephen C.
Published: April 2011

This article discusses the potential contribution of certain types of numerical data to explicitly interpretive, contextual inquiry (i.e., inquiry commonly associated with the use of “practical discourse” and “qualitative” methods) and extends an earlier argument on this topic. Three example studies that clarify this earlier argument, drawn from the research program of Yrjö Engeström, are presented. These examples provide concrete demonstrations of two principal ways in which Engeström used numerical data, in conjunction with data accrued through more traditional qualitative forms of inquiry (e.g., phenomenography, discourse analysis), to offer explicitly interpretive, contextual accounts of practical human action within dynamic “activity systems.”
Political clientelism and professional baseball in Taiwan: The merger between the two leagues in 2003
Authors: Lee Ping-Chao
Published: April 2011

This article examines the clientelistic relations which underpinned the activities of Taiwan’s society in the field of the professional baseball system. It highlights the significance of political clientelism as a key characteristic of the strategic environment which provides political and business groups and individuals space to pursue their interests. The article concludes that the continued existence of political clientelism, which has survived for decades, is unlikely to terminate, but rather emerge in new forms of social regulation, fostered and/or constrained by the social and economic structures of Taiwan’s society, where sport is inevitably subsumed.
Modeling the collagen fibril network of biological tissues as a nonlinearly elastic material using a continuous volume fraction distribution function
Authors: Shirazi Reza , Vena Pasquale , Sah Robert L. , Klisch Stephen M.
Published: April 2011

Despite distinct mechanical functions, biological soft tissues have a common microstructure in which a ground matrix is reinforced by a collagen fibril network. The microstructural properties of the collagen network contribute to continuum mechanical tissue properties that are strongly anisotropic with tensile-compressive asymmetry. In this study, a novel approach based on a continuous distribution of collagen fibril volume fractions is developed to model fibril reinforced soft tissues as nonlinearly elastic and anisotropic material. Compared with other approaches that use a normalized number of fibrils for the definition of the distribution function, this representation is based on a distribution parameter (i.e. volume fraction) that is commonly measured experimentally while also incorporating pre-stress of the collagen fibril network in a tissue natural configuration. After motivating the form of the collagen strain energy function, examples are provided for two volume fraction distribution functions. Consequently, collagen second-Piola Kirchhoff stress and elasticity tensors are derived, first in general form and then specifically for a model that may be used for immature bovine articular cartilage. It is shown that the proposed strain energy is a convex function of the deformation gradient tensor and, thus, is suitable for the formation of a polyconvex tissue strain energy function.
On mechanically induced degradation of fiber-reinforced hyperelastic materials
Authors: Baek Seungik , Pence Thomas J.
Published: April 2011

A finite strain model for the mechanical degradation of composite materials with multiple families of fine reinforcing fibers is developed and studied. At any instant of time the matrix material may or may not be degrading with all, some, or none of the interpenetrating fibers also undergoing degradation. This multi-component description of damage is governed by coupled differential equations when more than one damage mechanism is active. These differential equations, and the threshold values of the strain invariants that activate the damage process, emerge naturally from a general framework that describes the response of dissipative systems under a maximum rate of dissipation postulate. In this context we then study uniaxial loadings when either a constant stretch or a constant force is suddenly applied to the composite. It is found that the initial type of degradation (e.g. degrading fibers in a non-degrading matrix) may transition to an alternative type of degradation (e.g. the degradation of all constituents) at some finite time into the process. A rich variety of material and load-dependent transition possibilities are systematically uncovered using a combination of asymptotic and numerical techniques. The resulting macroscopic behavior as the material weakens involves relaxation and creep phenomena that are formally similar to viscoelastic material behavior in solids even though the underlying processes are significantly different. Describing implants and tissue constructs containing biodegradable polymers is one possible area of application.
Testing Hypothesized Psychosocial Mediators
Authors: Okechukwu Cassandra A. , Krieger Nancy , Sorensen Glorian , Li Yi , Barbeau Elizabeth M.
Published: April 2011

Only a few of the interventions that target blue-collar workers have conducted formal analysis to evaluate the specific attributes of their intervention that are associated with success or failure. This study examined the role of dual hazard and decisional balance in the MassBUILT smoking cessation intervention. The authors conducted sets of multivariable linear and logistic regressions that examined if (a) the intervention was associated with changes in the psychosocial variables and (b) increase in psychosocial variables was associated with increase in smoking cessation. As hypothesized by the theoretical basis of the study, higher scores on both of the psychosocial variables were significantly associated with smoking cessation. However, the intervention did not change decisional balance and decreased dual hazard. The variables examined were important but were not mediators of the MassBUILT intervention and this could have contributed to the significant relapse in smoking among study participants.
Spacing organization: non-representational theory and performing organizational space
Authors: Beyes Timon , Steyaert Chris
Published: April 2011

This article connects to and extends the attempts to bring space back into critical organizational theory, which, we argue, has mainly been based on the socio-spatial perspective as pioneered by Henri Lefebvre. Taking issue with the various ways in which Lefebvre’s work can be interpreted, we develop an alternative route. Adopting a mode of non-representational theorizing as outlined in human geography, we propose the concept of ‘spacing’, which orients the understanding of organizational space towards its material, embodied, affective and minor configurations. In discussing the consequences of such a performative approach to space for the practice and craft of organizational scholarship, we argue that our conceptual opening entails a move from representational strategies of extracting representations of the (organizational) world from the world to embodied apprehensions of the everyday performing of organizational space. What can be termed the enactment of organizational geographies in slow motion is inspired and illustrated by the video ‘The Raft’ conceived by the artist Bill Viola.
Homing in on excellence: Dimensions of appraisal in Center of Excellence program evaluations
Authors: Hellström Tomas
Published: April 2011

Excellence has become a watchword for goal setting and assessment in science and technology policy. While the concept has been around for many years in its commonsense meaning, it is now explicitly used for science governance; however, so far little work has been done to detail, operationalize and systematize the dimensions of value present in academic evaluators’ use of the concept. This article is based on a close reading of a mid-term evaluation of several centers of excellence in Sweden, the goal of which is to achieve a detailed understanding of the evaluative components of the concept. By applying template analysis to evaluation documents, seven main components, largely referring to the organizational/institutional aspects of excellence were identified. These are analyzed and used to provide insights for evaluation scholars and practitioners into the tensions and possibilities present in the excellence concept.
Modern Languages in the United Kingdom
Authors: Coleman James A.
Published: April 2011

The article supplies an overview of UK modern languages education at school and university level. It attends particularly to trends over recent years, with regard both to numbers and to social elitism, and reflects on perceptions of language learning in the wider culture and the importance of gaining wider recognition of the value of languages education.
Combined Direct Repair and Inline Inflow Stenting in the Management of Aortoiliac Disease Extending Into the Common Femoral Artery
Authors: Sharafuddin Melhem J. , Kresowik Timothy F. , Hoballah Jamal J. , Nicholson Rachael M. , Sharp William J.
Published: April 2011

Purpose: Describe a hybrid approach to simplify management of complex aortoiliac occlusive disease (AIOD) extending into the common femoral artery (CFA). Methods: Retrospective review of 56 patients who underwent hybrid management of AIOD extending into CFA between January 2003 and February 2007. Two distinct hybrid approaches were compared: Inline (iliac stenting continuous with an open CFA reconstruction, 38 limbs in 37 patients) and tandem (noncontiguous stenting of an upstream iliac segment, 20 limbs in 19 patients). The median follow-up duration was 15 ± 12 months in the inline group and 24 ± 12 months in the tandem group. Results: Technical success was achieved in all but 1 procedure. Clinical and hemodynamic responses to the interventions and limb loss rates were comparable in both groups. Survival table analysis showed no significant difference between inline and tandem reconstructions. Conclusions: Inline stenting represents a lesser invasive revascularization choice in complex AIOD with contiguous involvement of the CFA.
Delayed Complications of Inferior Vena Cava Filters: Case Report and Literature Review
Authors: Shang Eric K. , Nathan Derek P. , Carpenter Jeffrey P. , Fairman Ronald M. , Jackson Benjamin M.
Published: April 2011

Inferior vena cava (IVC) filters are frequently placed to prevent pulmonary embolism in patients in whom anticoagulation is contraindicated or ineffective. Delayed erosion of the filter into adjacent vital structures is a rare complication. We report 3 complications of IVC filters managed with both surgical and endovascular therapies. A review of the available literature addresses incidence of delayed IVC filter complications, the approach to these problems, and the role of retrievable IVC filters.
Complicated Acute Type B Thoracic Aortic Dissections: Endovascular Treatment For Visceral Malperfusion And Pseudoaneurysms
Authors: Naughton Peter A. , Garcia-Toca Manuel , Matsumura Jon S. , Rodriguez Heron E. , Morasch Mark D. , Resnick Scott A. , Eskandari Mark K.
Published: April 2011

Purpose: Morbidity and mortality of acute type B thoracic aortic dissections remain alarmingly high. Endoluminal options are promising. Methods: A single-center 5-year review of 17 acute type B aortic dissections complicated by visceral malperfusion (11) or pseudoaneurysm formation (6) treated with endovascular intervention. Interventional techniques included endografting (15) and/or percutaneous fenestration (4). Median follow-up is 28 months (range 0-76 months). Results: Median age was 55 years; 30-day death, stroke, and paraplegia rates were 0%, 17.6%, and 5.9%. Success reversing visceral ischemia or sealing a pseudoaneurysm was 100%. Cross-sectional imaging demonstrated that the false lumen was thrombosed in 9 patients, partially thrombosed in 6 patients. Late events include 1 delayed proximal type I endoleak, 1 delayed rupture of the thoracic aorta requiring successful emergent open surgical repair, and 2 unrelated late deaths. Conclusion: Endovascular approaches to type B dissections presenting with visceral malperfusion and/or pseudoaneurysm can achieve acceptable early results.
Ultrasound Accelerated Catheter Directed Thrombolysis for Pulmonary Embolus and Right Heart Thrombus Secondary to Transvenous Pacing Wires
Authors: Amankwah Kwame S. , Seymour Keri , Costanza Michael J. , Gahtan Vivian
Published: April 2011

Acute pulmonary embolism is associated with a significant number of deaths each year, which are commonly attributed to deep venous thrombosis of the lower extremity. Pulmonary embolism due to right-sided cardiac thrombus associated with transvenous wires is a rare occurrence. Treatment considerations have been systemic anticoagulation with heparin or systemic thrombolytic therapy. A unique case of a patient with symptomatic PE and extensive atrial and ventricle thrombus formation associated with transvenous pacing wires treated with ultrasound accelerated catheter directed thrombolysis is presented.
Incidence and Survival Outcome Following Femoral Artery Reconstruction During Endovascular Abdominal Aortic Aneurysm Repair
Authors: Twine Christopher P. , Wood Andrew , Gordon Andrew , Hill Susan , Whiston Richard , Williams Ian M.
Published: April 2011

Background: Planned or unplanned reconstruction of the common femoral artery (femoro-femoral crossover and/or patch closure) may be required following endovascular abdominal aortic aneurysm repair (EVAR) stent graft deployment for arterial closure or maintenance of limb perfusion. The aim of this study was to examine the incidence of common femoral artery reconstruction (FAR) following EVAR and examine the effect on patient survival. Methods: A total of 178 patients undergoing EVAR were studied retrospectively. Results: In all, 31 patients (17.4%) underwent FAR; 16 (51.6%) femoro-femoral crossover, and 15 (48.4%) endarterectomy and patch closure. All cause survival in patients undergoing FAR was significantly poorer than those undergoing direct closure (P = .010).A total of 3 factors: the need for FAR (hazard ratio [HR] = 0.435, P = .006), chronic obstructive pulmonary disease ([COPD] HR = 0.424, P = .002), and abdominal aortic aneurysm (AAA) size (HR = 1.414, P = .005) were significantly and independently associated with survival on forward conditional analysis. Conclusions: Femoral artery reconstruction was performed in almost 1 in 5 patients undergoing EVAR and associated with decreased survival. Multidisciplinary teams should be aware of these findings when planning EVAR, especially in borderline candidates.
The use of group sequential, information-based sample size re-estimation in the design of the PRIMO study of chronic kidney disease
Authors: Pritchett Yili , Jemiai Yannis , Chang Yuchiao , Bhan Ishir , Agarwal Rajiv , Zoccali Carmine , Wanner Christoph , Lloyd-Jones Donald , Cannata-Andía Jorge B , Thompson Taylor , Appelbaum Evan , Audhya Paul , Andress Dennis , Zhang Wuyan , Solomon Scott , Manning Warren J , Thadhani Ravi
Published: April 2011

Background Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies.

Purpose PRIMO ( Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease.

Methods Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis.

Limitations If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making.

Conclusions The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.
Did the Global War on Terror end the CNN effect?
Authors: Bahador Babak
Published: April 2011

While the Global War on Terror (GWOT) aimed to eradicate terrorists, it also allegedly claimed another casualty — independent media coverage of foreign policy — a key component of the CNN effect. To many analysts of this media effect, the launch of the GWOT clarified foreign policy priorities, much like the Cold War era. From this perspective, the media, which enjoyed relative freedom in their foreign policy coverage in the 1990s, became subservient to the state again after 9/11. This article challenges this conventional wisdom by first arguing that the media’s foreign news agenda did not significantly change with the GWOT. However, problems with the notion of independent media framing, which existed in the 1990s, continued post-9/11. The article offers a nuanced understanding of the CNN effect that places the media’s influence within the existing foreign policy decision-making structure. It also shows how the CNN effect can be a sustainable concept regardless of changing international security environments.
Media selectivity and the other side of the CNN effect: the consequences of not paying attention to conflict
Authors: Hawkins Virgil
Published: April 2011

Most of the world’s conflicts take place largely unreported by the media, and the deadliest conflicts are among those ignored. If we assume that the media do have the power to influence policy responses to conflict, it follows that, by ignoring conflict, the media contribute to the lack of policy response. This article suggests that a major consequence of this effect is unchecked conflict-related death tolls (mostly indirect deaths caused by sickness and starvation) since little progress is made in achieving conflict resolution, the waging of the conflict is unrestrained, and relatively little humanitarian aid is forthcoming. With so few chosen conflicts and so many ‘off the radar’ stealth conflicts, the stakes of such media choices are high. This article focuses on this other side of the CNN effect, examining just how selectively and disproportionately the media cover conflict, and on the consequences of the lack of attention.
Attitudes of General Practitioner Registrars and Their Trainers Toward Obesity Prevention in Adults
Authors: Aucott Lorna Sharman , Riddell Rebecca E. , Smith W. Cairns S.
Published: April 2011

Obesity prevalence in developed countries is around 25% and rising. Prevention is beginning to receive attention. In the United Kingdom, general practice provides services to most of the population; on average, a patient is seen 4 times a year. Doctors’ attitudes toward obesity prevention have not been well documented. Objectives: Obtain doctors’ views toward obesity prevention and determine any differences between registrars and their trainers. Methods: During 2006-2007, a postal questionnaire was sent to all general practitioner registrars in Scotland and their trainers. The questions included individual details, opinions about current obesity prevention strategies, and facts about current obesity prevention practices. Results: Of those targeted (103 registrars, 91 trainers), 51% responded, representing 5% of all general practitioners in Scotland. Most agreed obesity and its prevention were important. However, more experienced practitioners were less convinced as to whether primary care could or should help with obesity prevention. Individual change was viewed as important, whereas primary care screening was of least importance. Conclusion: As the largest survey on doctors’ attitudes about obesity prevention, these results indicate that obesity and its prevention are important but that there are concerns and differences between registrars and trainers, in that trainers are more neutral about their agreement. A multifaceted approach building on current good practices of general practitioners with support from other specialty care providers may help to minimize the risk of alienation, fear, and resistance to primary care involvement for both treatment and prevention of obesity. However, resources and training would be necessary, along with methods to protect the doctor/patient relationship.
Histone modification enhances the effectiveness of IL-13 receptor targeted immunotoxin in murine models of human pancreatic cancer
Authors: Fujisawa Toshio , Joshi Bharat H , Puri Raj K
Published: April 2011

Background

Interleukin-13 Receptor α2 (IL-13Rα2) is a tumor-associated antigen and target for cancer therapy. Since IL-13Rα2 is heterogeneously overexpressed in a variety of human cancers, it would be highly desirable to uniformly upregulate IL-13Rα2 expression in tumors for optimal targeting.

Methods

We examined epigenetic regulation of IL-13Rα2 in a murine model of human pancreatic cancer by Bisulfite-PCR, sequencing for DNA methylation and chromatin immunoprecipitation for histone modification. Reverse transcription-PCR was performed for examining changes in IL-13Rα2 mRNA expression after treatment with histone deacetylase (HDAC) and c-jun inhibitors. In vitro cytotoxicity assays and in vivo testing in animal tumor models were performed to determine whether HDAC inhibitors could enhance anti-tumor effects of IL-13-PE in pancreatic cancer. Mice harboring subcutaneous tumors were treated with HDAC inhibitors systemically and IL-13-PE intratumorally.

Results

We found that CpG sites in IL-13Rα2 promoter region were not methylated in all pancreatic cancer cell lines studied including IL-13Rα2-positive and IL-13Rα2-negative cell lines and normal cells. On the other hand, histones at IL-13Rα2 promoter region were highly-acetylated in IL-13Rα2-positive but much less in receptor-negative pancreatic cancer cell lines. When cells were treated with HDAC inhibitors, not only histone acetylation but also IL-13Rα2 expression was dramatically enhanced in receptor-negative pancreatic cancer cells. In contrast, HDAC inhibition did not increase IL-13Rα2 in normal cell lines. In addition, c-jun in IL-13Rα2-positive cells was expressed at higher level than in negative cells. Two types of c-jun inhibitors prevented increase of IL-13Rα2 by HDAC inhibitors. HDAC inhibitors dramatically sensitized cancer cells to immunotoxin in the cytotoxicity assay in vitro and increased IL-13Rα2 in the tumors subcutaneously implanted in the immunodeficient animals but not in normal mice tissues. Combination therapy with HDAC inhibitors and immunotoxin synergistically inhibited growth of not only IL-13Rα2-positive but also IL-13Rα2-negative tumors.

Conclusions

We have identified a novel function of histone modification in the regulation of IL-13Rα2 in pancreatic cancer cell lines in vitro and in vivo. HDAC inhibition provides a novel opportunity in designing combinatorial therapeutic approaches not only in combination with IL-13-PE but with other immunotoxins for therapy of pancreatic cancer and other cancers.
Optical identification of electronic state levels of an asymmetric InAs/InGaAs/GaAs dot-in-well structure
Authors: Zhou Xiaolong , Chen Yonghai , Xu Bo
Published: April 2011

We have studied the electronic state levels of an asymmetric InAs/InGaAs/GaAs dot-in-well structure, i.e., with an In0.15Ga0.85As quantum well (QW) as capping layer above InAs quantum dots (QDs), via temperature-dependent photoluminescence, photo-modulated reflectance, and rapid thermal annealing (RTA) treatments. It is shown that the carrier transfer via wetting layer (WL) is impeded according to the results of temperature dependent peak energy and line width variation of both the ground states (GS) and excited states (ES) of QDs. The quenching of integrated intensity is ascribed to the thermal escape of electron from the dots to the complex In0.15Ga0.85As QW + InAs WL structure. Additionally, as the RTA temperature increases, the peak of PL blue shifts and the full width at half maximum shrinks. Especially, the intensity ratio of GS to ES reaches the maximum when the energy difference approaches the energy of one or two LO phonon(s) of InAs bulk material, which could be explained by phonon-enhanced inter-sublevels carrier relaxation in such asymmetric dot-in-well structure.

PACS: 73.63.Kv; 73.61.Ey; 78.67.Hc; 81.16.Dn
Organic nanofibers integrated by transfer technique in field-effect transistor devices
Authors: Tavares Luciana , Kjelstrup-Hansen Jakob , Thilsing-Hansen Kasper , Rubahn Horst-Günter
Published: April 2011

The electrical properties of self-assembled organic crystalline nanofibers are studied by integrating these on field-effect transistor platforms using both top and bottom contact configurations. In the staggered geometries, where the nanofibers are sandwiched between the gate and the source-drain electrodes, a better electrical conduction is observed when compared to the coplanar geometry where the nanofibers are placed over the gate and the source-drain electrodes. Qualitatively different output characteristics were observed for top and bottom contact devices reflecting the significantly different contact resistances. Bottom contact devices are dominated by contact effects, while the top contact device characteristics are determined by the nanofiber bulk properties. It is found that the contact resistance is lower for crystalline nanofibers when compared to amorphous thin films. These results shed light on the charge injection and transport properties for such organic nanostructures and thus constitute a significant step forward toward a nanofiber-based light-emitting device.
Protein kinase C-α signals P115RhoGEF phosphorylation and RhoA activation in TNF-α-induced mouse brain microvascular endothelial cell barrier dysfunction
Authors: Peng Jing , He Fang , Zhang Ciliu , Deng Xiaolu , Yin Fei
Published: April 2011

Background

Tumor necrosis factor-α (TNF-α), a proinflammatory cytokine, is capable of activating the small GTPase RhoA, which in turn contributes to endothelial barrier dysfunction. However, the underlying signaling mechanisms remained undefined. Therefore, we aimed to determine the role of protein kinase C (PKC) isozymes in the mechanism of RhoA activation and in signaling TNF-α-induced mouse brain microvascular endothelial cell (BMEC) barrier dysfunction.

Methods

Bend.3 cells, an immortalized mouse brain endothelial cell line, were exposed to TNF-α (10 ng/mL). RhoA activity was assessed by pull down assay. PKC-α activity was measured using enzyme assasy. BMEC barrier function was measured by transendothelial electrical resistance (TER). p115RhoGEF phosphorylation was detected by autoradiography followed by western blotting. F-actin organization was observed by rhodamine-phalloidin staining. Both pharmacological inhibitors and knockdown approaches were employed to investigate the role of PKC and p115RhoGEF in TNF-α-induced RhoA activation and BMEC permeability.

Results

We observed that TNF-α induces a rapid phosphorylation of p115RhoGEF, activation of PKC and RhoA in BMECs. Inhibition of conventional PKC by Gö6976 mitigated the TNF-α-induced p115RhoGEF phosphorylation and RhoA activation. Subsequently, we found that these events are regulated by PKC-α rather than PKC-β by using shRNA. In addition, P115-shRNA and n19RhoA (dominant negative mutant of RhoA) transfections had no effect on mediating TNF-α-induced PKC-α activation. These data suggest that PKC-α but not PKC-β acts as an upstream regulator of p115RhoGEF phosphorylation and RhoA activation in response to TNF-α. Moreover, depletion of PKC-α, of p115RhoGEF, and inhibition of RhoA activation also prevented TNF-α-induced stress fiber formation and a decrease in TER.

Conclusions

Taken together, our results show that PKC-α phosphorylation of p115RhoGEF mediates TNF-α signaling to RhoA, and that this plays a critical role in signaling F-actin rearrangement and barrier dysfunction in BMECs.
Gastrointestinal toxicity of vorinostat: reanalysis of phase 1 study results with emphasis on dose-volume effects of pelvic radiotherapy
Authors: Bratland Åse , Dueland Svein , Hollywood Donal , Flatmark Kjersti , Ree Anne H
Published: April 2011

Background

In early-phase studies with targeted therapeutics and radiotherapy, it may be difficult to decide whether an adverse event should be considered a dose-limiting toxicity (DLT) of the investigational systemic agent, as acute normal tissue toxicity is frequently encountered with radiation alone. We have reanalyzed the toxicity data from a recently conducted phase 1 study on vorinostat, a histone deacetylase inhibitor, in combination with pelvic palliative radiotherapy, with emphasis on the dose distribution within the irradiated bowel volume to the development of DLT.

Findings

Of 14 eligible patients, three individuals experienced Common Terminology Criteria of Adverse Events grade 3 gastrointestinal and related toxicities, representing a toxicity profile vorinostat has in common with radiotherapy to pelvic target volumes. For each study patient, the relative volumes of small bowel receiving radiation doses between 6 Gy and 30 Gy at 6-Gy intervals (V6-V30) were determined from the treatment-planning computed tomography scans. The single patient that experienced a DLT at the second highest dose level of vorinostat, which was determined as the maximum-tolerated dose, had V6-V30 dose-volume estimates that were considerably higher than any other study patient. This patient may have experienced an adverse radiation dose-volume effect rather than a toxic effect of the investigational drug.

Conclusions

When reporting early-phase trial results on the tolerability of a systemic targeted therapeutic used as potential radiosensitizing agent, radiation dose-volume effects should be quantified to enable full interpretation of the study toxicity profile.

Trial registration

ClinicalTrials.gov: NCT00455351
Introduction to this special section: Geoscientists Without Borders
Authors: Beasley Craig J. , Pellerin Louise , van der Kruk Jan , Jacobs Rhonda
Published: April 2011

Neither introduction nor motivation are required for this special section of The Leading Edge dedicated to the SEG Foundation's program Geoscientists Without Borders (GWB). Natural disasters such as earthquakes, tsunamis, volcanic eruptions, killer storms, landslides, and other natural disasters occur all too frequently. People across the planet struggle to provide themselves the basic necessities of life such as water, food, and energy. While we, as geophysicists, cannot control nature or eliminate the human condition, it is possible for us to play a role in mitigating these problems and improving human lives. We can all contribute as individuals, but the goal of GWB is larger: to effect long-term and sustainable aid to people in need through technology transfer and training involving the next generation of geoscientists.
Assessing geohazards near Kingston, Jamaica: Initial results from chirp profiling
Authors: Hornbach Matthew J. , Mann Paul , Frohlich Cliff , Ellins Kathy , Brown Lyndon
Published: April 2011

Kingston, Jamaica, the capital of the Caribbean island nation of Jamaica, is prone to infrequent but devastating earthquakes and tsunamis, yet the locations of the faults responsible for generating these geohazards are poorly known. The city rests precariously at the western terminus of the Enriquillo Plantain Garden Fault (EPGF)—the same fault that ruptured during the 12 January 2010 Haiti earthquake, destroying Port-au-Prince and killing about 250,000 people (Figure 1 inset). Like Haiti, Jamaica has experienced a significant earthquake every few hundred years; however, the exact frequency and location of large earthquakes across Jamaica remain unclear. In the past 300 years, Jamaica has experienced at least two earthquakes (in 1692 and 1907) comparable to the 2010 Haiti earthquake and, like Haiti, these earthquakes caused significant loss of life, triggered tsunamis, slope failure, and caused widespread ground liquefaction (e.g., Sloane, 1694; Tabor, 1920). The 1907 earthquake killed ∼1000 people in Kingston. The 1692 earthquake completely destroyed Port Royal, a city then notorious as a haven for privateers and as the Western Hemisphere's center for slaving operations.
Recognizing stakeholders in the design of effective community-level geophysics programs
Authors: Moysey Stephen
Published: April 2011

Despite the challenges involved in implementing “humanitarian geophysics” projects, the potential impact of these projects is vast—particularly for engaging the public and encouraging a new and diverse generation of students to pursue careers in geophysics. Established programs like Engineers without Borders and emerging programs like Geoscientists Without Borders (GWB), which is administered through the SEG Foundation, provide unprecedented opportunities for geoscientists to become engaged in projects with a humanitarian focus. Many of us are excited by the prospect of using our knowledge and skills to make impacts on communities in a direct and immediate way. As scientists, it is easy for us to focus on addressing the technical issues of a project, such as selecting appropriate measurement methods and overcoming the daunting logistics of field operations—particularly if the project is in a foreign country. To create effective programs, however, it is equally important for us to consider nontechnical issues in the planning phase of a project, such as the role of stakeholders.
An introduction to this special section: Offshore technology
Authors: Knobloch Charles
Published: April 2011

From 1–5 May 2011, SEG will again cosponsor the Offshore Technology Conference, commonly known this year as OTC.11, the world's foremost event for the development of offshore resources in the fields of drilling, exploration, production, and environmental protection. OTC, founded in 1969, is now held annually at Reliant Center in Houston.
Missing and duplicate sample phenomenon in marine seismic data recording: Causes and quality-control procedures for its detection
Authors: Vidal David , Alarcón Pablo , Deiros Diego
Published: April 2011

Modern marine seismic data acquisition systems are typically assumed to be robust and error-free in operation. This paper discusses a case history where that assumption was false due to a combination of ocean currents, improper system setup, and overheating on the recording instruments.
Sex Differences in Lipid and Lipoprotein Metabolism: It's Not Just about Sex Hormones
Authors: Wang Xuewen , Magkos Faidon , Mittendorfer Bettina
Published: April 2011

It is commonly thought that sex hormones are important regulators of plasma lipid kinetics and are responsible for sexual dimorphism in the plasma lipid profile. Here we discuss the findings from studies evaluating lipid and lipoprotein kinetics in men and women in the context of what we know about the effects of exogenous sex hormone administration, and we conclude that it is more complicated than that. It has become clear that normal physiological alterations in the hormonal milieu (i.e. due to menopause or throughout the menstrual cycle) do not significantly affect plasma lipid homeostasis. Furthermore, parenterally administered estrogens have either no effect or only very small beneficial effects, whereas orally administered estrogens raise plasma triglyceride concentrations—a phenomenon that is not consistent with the observed sex differences and likely results from the hepatic “first-pass effect.” The effects of progestogens and androgens mimic only in part the differences in plasma lipids between men and women. Thus, the underlying physiological modulators of plasma lipid metabolism responsible for the differences between men and women remain to be elucidated.
An Optimal Constraint Programming Approach to the Open-Shop Problem
Authors: Malapert Arnaud , Cambazard Hadrien , Guéret Christelle , Jussien Narendra , Langevin André , Rousseau Louis-Martin
Published: April 2011

This paper presents an optimal constraint programming approach for the open-shop scheduling problem, which integrates recent constraint propagation and branching techniques with new upper bound heuristics. Randomized restart policies combined with nogood recording allow us to search diversification and learning from restarts. This approach is compared with the best-known metaheuristics and exact algorithms, and it shows better results on a wide range of benchmark instances.