bluuebunny/crossref_metadata_2025 huggingface dataset:
The Politics of Public Policy in Ghana
Authors: Kpessa Michael W.
Published: February 2011

This article examines the trajectories and approaches to public policy making in Africa. Using process tracing interlaced with analysis of historical records, secondary literature, and elite interviews, the article shows that since the 1990s, policy making in some African countries, especially Ghana, has been witnessing a gradual shift away from bureaucratic approaches to policy making to the ones that directly engage the citizenry through consultation and open public participation. The article shows that this shift to citizenry participation is largely due to an emphasis in the development literature on good governance broadly defined to include public participation, and the view of civil society as a platform for social transformation. The article provides a step-by-step analysis of strategies used in recent social security reforms in Ghana to illustrate this change in approach to public policy, and shows that public participation approach to policy making is fraught with several structural challenges and impediments that not only privilege elites’ preferences over the unorganized rural dwellers but also questions some of the fundamental principles of the good governance mantra.
Beyond the “Geography of Terrorism and Terror of Geography” Thesis
Authors: Ogundiya Ilufoye Sarafa
Published: February 2011

The Niger Delta predicament has fascinated academic curiosity and intellectual nosiness in the recent time. Thus, several analytical frameworks and theoretical postulations have been adopted in the explanation of the Niger Delta quandary. One of the competing explanations is the “geography of terrorism or terror of geography” thesis which construed the inauspicious geography and murky topography of the region as a major factor that precipitates development tragedy. The article argues that beyond the terror of geography thesis is the endemic political and bureaucratic corruption that has engulfed the Nigerian political system at all levels of government. To buttress this contention, the article has gathered and analyzed the allocation to Niger Delta states, relative to states in other geopolitical zones, for a period of five years, from 2004 to 2008, and concludes that the problem with Niger Delta is not only a problem of resource allocation and a problem of geography, but majorly a problem of endemic political and bureaucratic corruption.
Best Practices for Evaluation of Bone Marrow in Nonclinical Toxicity Studies
Authors: Reagan William J. , Irizarry-Rovira Armando , Poitout-Belissent Florence , Bolliger Anne Provencher , Ramaiah Shashi K. , Travlos Greg , Walker Dana , Bounous Denise , Walter Gail ,   Bone Marrow Working Group of ASVCP/STP
Published: February 2011

This manuscript is intended to provide a best practice approach to accurately and consistently assess toxicant-induced bone marrow effects of test articles. In nonclinical toxicity studies, complete blood count data in conjunction with the histological examination of the bone marrow are recommended as the foundation for assessing the effect of test articles on the hematopoietic system. This approach alone can be used successfully in many studies. However, in some situations it may be necessary to further characterize effects on the different hematopoietic lineages, either by cytological or flow cytometric evaluation of the bone marrow. Both modalities can be used successfully, and which one is selected will depend on the expertise, preference of the facility, and the nature of the change in the bone marrow. Other specialized techniques such as clonogenic assays or electron microscopy are used rarely to further characterize hematotoxicity. The indications and techniques to successfully employ histological, cytological, or flow cytometric evaluation as well as clonogenic assays and electron microscopy are reviewed.
Managing the Voices: Athlete Self-Talk as a Dialogic Process
Authors: Tovares Alla V.
Published: February 2011

Studies in sport psychology focus on “self-talk” as a motivational and instructional tool to enhance athletic performance. This article (re)conceptualizes self-talk as a dialogic phenomenon that is foundational to the construction of athletic identity. Through a detailed analysis of athletes’ oral and written narratives, the author demonstrates how Bakhtin’s internal polemic not only adds to the current understanding of athlete self-talk but also offers a productive lens for investigating how athletes display, perform, and construct identities. The analysis extends current conceptualizations of athlete self-talk, which provides a nuanced understanding of how athletes manage those internal voices that affect athletic performance.
Sport, Language, and Culture: Issues and Intersections
Authors: Meân Lindsey J. , Halone Kelby K.
Published: February 2011

This article introduces a special issue on sport, language, and culture.We briefly outline the individual, social, and cultural significance of sport, asserting it as an important site for scholarly theory and research. But sport is a dynamic site that occurs across multiple levels (individuals, teams, organizations, locales, cultures, and nations). We argue that language, representations, and other discursive practices are pivotal for the construction and enactment of sport across these multiple levels. Of the many interconnections and intersections of sport, language, and culture, we further contend that identities and media are crucial; and it is these that provide a resonating link between the articles that comprise the special issue.
Situating Sport, Language, and Culture as a Site for Intellectual Discussion
Authors: Halone Kelby K. , Meân Lindsey J.
Published: February 2011

The articles in this special issue provide an opportunity to illustrate how the domain of “sport, language, and culture” can become a burgeoning site for future intellectual discussion. We extend this discussion by offering frameworks that (a) suggestively characterize how these articles collectively speak to issues of sport, language, and culture and (b) provide a template for the future development of transdisciplinary theory and research. The special issue provides a unique opportunity to appropriately illustrate how diversity in intellectual perspective and disciplinary approach is necessary for productively creating a unified domain of scholarly interest.
The Power of Stereotypes: Anchoring Images Through Language in Live Sports Broadcasts
Authors: Desmarais Fabrice , Bruce Toni
Published: February 2011

Televised sport offers a rich context for investigating the processes that influence particular uses of language. Here, the authors consider how pressure on sport commentators to connect with audiences results in reliance on preestablished narratives that draw heavily on stereotypes. They investigate how television sport commentators negotiate tensions between stereotypes of a particular country’s playing style and on-field action that challenges those stereotypes. Their interdisciplinary approach—drawing from social psychology, communication, media studies, sport studies, and cultural studies—provides a textual analysis of New Zealand commentary in a pivotal Rugby World Cup game between France and New Zealand. The authors identify three different ways in which national stereotypes lead commentators to produce interpretations that do not always accurately represent the action on the field. They conclude that sport commentary in an international context operates to create and reinscribe symbolic differences between nations, even in the face of visual evidence that is ambiguous or actively contradicts the words used to describe it. The analysis demonstrates how powerfully national stereotypes influence commentators’ representational choices.
The embodied organization of a real-time fetus: The visible and the invisible in prenatal ultrasound examinations
Authors: Nishizaka Aug
Published: February 2011

Through an analysis of videotaped interactions between healthcare professionals and pregnant women during ultrasound prenatal examinations in Japan, I explore some aspects of sequence organization in which an ultrasound real-time fetus is organized. The ultrasound demonstration of the fetal condition is an intrinsically interactional and distributed achievement. The ultrasound fetus is constructed as a real-time object in a particular technological environment; in this environment, the participants’ orientations to spatially separated operational fields, that is, the monitor screen and the woman’s abdomen, are exhibited and integrated in the actual course of interaction. In conclusion, the fundamental relation between organizational lived work in a technological environment and the observable features of technology will be suggested.
Genomic designation: How genetics can delineate new, phenotypically diffuse medical categories
Authors: Navon Daniel
Published: February 2011

This paper reports and discusses ‘genomic designation’ as a way of classifying people. In genomic designation the object of biomedical analysis — and the concomitant medical category that is subject to scientific, clinical, and social action — is delineated on a genomic basis, while the phenotype is decentralized and tabulated post factum. Unlike prominent sociological concepts such as biosociality or geneticization, where genetic proclivities for or explanations of phenotypic categories affect social processes, genomic designation treats characteristics of the genome as the essential referent of new categories of illness. I outline the relevant sociological literature and the shift to what Nikolas Rose has called the ‘molecular gaze’ before explicating the concept of genomic designation and its half-century history. I use 22q13 Deletion/Phelan—McDermid syndrome as an example of genomic designation: investigations into the deletion of genetic material at site q13 on the 22nd chromosome preceded and made practicable the delineation of a syndrome more than a decade later, even though the associated phenotype is not distinct enough for diagnosis. Finally, I discuss the implications of this turn to ‘rigidly designate’ kinds of people according to observations made at the level of the genome and outline directions for future research.
Use of the tapered double-cantilever beam geometry for fracture toughness measurements and its application to the quantification of self-healing
Authors: Brown E N
Published: February 2011

The successful invention of self-healing polymer composites a decade ago necessitated a methodology to quantify the ability of the material to heal and recover structural properties following damage. Healing efficiency was defined as the ratio of healed to virgin fracture toughness, η =  KIChealed/ KICvirgin. Early work took advantage of the crack length independence offered by a tapered double-cantilever beam (TDCB) fracture geometry to simplify calculation of healing efficiency to the ratio of healed to virgin critical loads, η =  PChealed/ PCvirgin. The current work investigates the application of the TDCB geometry and three common geometries utilized in the broader fracture literature (the compact tension (CT), single-edge notch bend (SENB), and single-edge notch tension (SENT) geometries) to the measurement of healing efficiency. While the TDCB geometry simplifies the calculation of healing efficiency because the crack lengths do not need to be accounted for, it is shown that if the virgin and healed crack lengths are not accurately accounted when using the CT, SENB, and SENT geometries, errors in calculated healing efficiency can be several hundred per cent. The TDCB geometry is reviewed at length, including the underlying theory and experimental calibration and validation of TDCB geometry.
Stress fields due to inclined notches and shoulder fillets in shafts under torsion
Authors: Zappalorto M , Lazzarin P
Published: February 2011

Closed-form expressions of the stress fields in notched rounded bars subjected to torsion are obtained. The notch profile is mathematically described according to Neuber’s conformal mapping z = ( u +  iv) q, which gives parabolic and hyperbolic profiles depending on q. The notch axis is inclined with respect to the rounded bar axis. This condition results in two eigenvalue functions: the former is associated with the antisymmetric stress field and gives a stress distribution of asymptotic nature when the notch radius is equal to zero. Conversely, the latter is associated with the symmetric stress field and results in a non-singular stress distribution. This specific condition has been noted in the literature only rarely, where only the antisymmetric part of the stress field is discussed in detail. Theoretical results are compared with numerical data as determined from two models weakened by a parabolic notch and a hyperbolic notch, both notches having the local axis inclined to 45° with respect to the bar longitudinal axis. The agreement is found to be satisfactory.
A Novel Imaging Method for Osteochondral Lesions of the Talus—Comparison of SPECT-CT With MRI
Authors: Leumann André , Valderrabano Victor , Plaass Christian , Rasch Helmut , Studler Ueli , Hintermann Beat , Pagenstert Geert I.
Published: February 2011

Background: Magnetic resonance imaging (MRI) is the current standard in noninvasive diagnostics of osteochondral lesions (OCLs) of the talus. Single-photon emission computed tomography–computed tomography (SPECT-CT) is a new technique that displays different imaging qualities. The influence of the aforementioned diagnostic information on treatment decision making in talar OCLs is not known.

Purpose: The aim of the study was to evaluate SPECT-CT in comparison with MRI for image interpretation and decision making in OCLs of the talus.

Study Design: Case series; Level of evidence, 4.

Methods: Magnetic resonance imaging and SPECT-CT of 25 patients (average age, 32 years; range, 18-69 years) were analyzed by 3 independent orthopaedic surgeons blinded to the study. Raters had to analyze images for predefined criteria of cartilage, subchondral bone plate, and subchondral bone, including bone marrow edema on MRI and scintigraphic activity on SPECT-CT. For MRI alone, SPECT-CT alone, and their combination, the treatment decision had to be defined.

Results: In comparison with MRI alone, treatment decision making changed in 48% of the cases with SPECT-CT alone and 52% with SPECT-CT and MRI combined. While cartilage showed good correlation for interpretation between MRI and SPECT-CT, the subchondral bone plate and subchondral bone showed substantial differences. Poor intrarater correlation highlighted the different information provided by the 2 imaging techniques. Poor interrater correlation showed a high heterogeneity in the treatment decision making of OCLs.

Conclusion: Compared with MRI, SPECT-CT provides additional information and influences the decision making of OCL treatment. For thorough diagnostic evaluation in OCLs, performing both MRI and SPECT-CT is recommended. Further clinical investigation is needed to see if SPECT-CT in addition to MRI results in improved treatment outcomes.
Structural polymer composite materials for muscle-skeletal diagnostic systems
Authors: Pernice M.F. , Annicchiarico D. , Petriccione A. , De Tommaso G. , Meo M. , Antonucci V. , Zarrelli M.
Published: February 2011

The aim of the study presented herein was to investigate the possibility of employing composites in the production of medical diagnostic equipments, and their advantages in terms of costs and performances. In particular, the patient-positioning system of a magnetic resonance apparatus, comprising two elements, the bed tables, and the footrest, was examined with the main goal of enabling a wider range of population to be tested, thanks to a full re-designing of their item. An extensive variety of composites were investigated, in order to select a combination of matrix and reinforcement able to satisfy the specific requirements in terms of magnetic transparency, structural behavior, manufacturing features, and costs. Glass fiber composites were selected and characterized by experimental tests. The patient-positioning system was completely re-designed and analyzed by finite elements method; design optimization led to a simplified structure, offering a series of advantages such as light weight, manoeuvrability, thickness reduction, and cost-saving processes. Final full-scale prototypes were realized and tested according to the Medical Security procedures, achieving as main results not only a reduction of the total production cost, but also an increase in the percentage of people that can be scanned by this magnetic resonance apparatus.
Effects of temperature, seawater and impact on the strength, stiffness, and life of sandwich composites
Authors: Singh Abhendra K. , Davidson Barry D.
Published: February 2011

A study was conducted to determine the effects of subzero temperatures, seawater saturation, and low velocity impact on the flexural strength, stiffness, and life of sandwich composites. Specimens were tested statically and in fatigue using a four-point bending arrangement that included a combined metal and rubber load pad that spanned the inner loading heads and which prevented any local crushing damage. Both undamaged and impact damaged specimens were tested in room temperature (RT) dry, RT seawater saturated, -20°C dry, and -20°C seawater saturated environments. The impact energy level was chosen to produce damage that was observable, yet did not produce excessive permanent deformation. The primary results were that reducing the temperature tended to increase stiffness, strength, and fatigue life. Seawater saturation had minimal effects on strength, stiffness, or life, but influenced the static failure mode. Impact damage had little effect on the static results, but caused a significant loss in fatigue life. These results demonstrate that static test results cannot be used to infer fatigue behaviors, and indicate the need for the accurate determination of material and structural responses across the full range of expected usage environments.
Swedish Health Care Professionals’ View of Frailty in Older Persons
Authors: Gustafsson Susanne , Edberg Anna-Karin , Dahlin-Ivanoff Synneve
Published: February 2011

There is a paucity of research literature concerning frailty in older persons from the health care professionals’ perspective. Consequently, the purpose of this study was to elucidate health care professionals’ view of frailty in older persons. An explorative, qualitative design was selected and four focus groups comprising 21 health care professionals were conducted, audiotaped, transcribed verbatim, and analyzed. Frailty was found to consist of seven dimensions: “being bodily weak and ill,” “being negatively influenced by personal qualities,” “lacking balance in everyday activities,” “being dependent in everyday life,” “not being considered important,” “being hindered by the physical milieu and defective community service,” and “having an inadequate social network.” The results showed that health care professionals’ view of frailty in older persons differed from the current state of knowledge on frailty. This implies that the seven dimensions found to constitute frailty could contribute to a more comprehensive understanding of the concept.
Roles, Responsibilities, and Concerns of Paraeducators
Authors: Fisher Mary , Pleasants Stacia L.
Published: February 2011

The purpose of this survey study was to obtain descriptive information about job situations of special education paraeducators from paraeducators across one state and determine their perceptions regarding roles, current issues identified in the literature, and other issues of concern. Of particular interest was whether perceptions varied based on (a) paraeducator assignment (one-to-one or group) or (b) time in general education settings. More than 1,800 paraeducators responded. Findings supported previous studies based on smaller samples. Problematic issues previously associated with one-to-one paraeducators in general education settings were reported as concerns by both one-to-one and group paraeducators who spent all or most of their day in self-contained settings. Discussion centers on the importance of “paraeducator voice” in efforts to address broader issues of inclusive schooling, clarification of paraeducators as instructional team members, and better understandings situated in practice of the paraeducator role as an effective intervention alternative sometimes for students with individualized education programs.
Influenza A 2009 (H1N1) Virus in Admitted and Critically Ill Patients
Authors: Miller Andrew C. , Subramanian Ramanand A. , Safi Farnaz , Sinert Richard , Zehtabchi Shahriar , Elamin Elamin M.
Published: February 2011

Introduction: The influenza A 2009 (H1N1) virus is a pandemic respiratory infection commanding international attention. More information is needed on patient demographics, illness severity, and risk indicators. Methods: A total of 43 patients with H1N1 influenza A 2009 presenting to 2 urban academic medical centers during the first wave were assessed for demographics, triage vital signs, hemograms, and serum chemistries including lactate. Chest X-rays were assessed for infiltrate or effusion. Illness severity markers were recorded including anion gap (AG), strong ion gap (SIG), systemic inflammatory response syndrome score, shock index, confusion, uremia, respiratory rate, blood pressure, and age >= 65 years (CURB-65) score, and pneumonia severity index. Subgroup analysis was performed on asthmatic, pregnant, and intensive care unit (ICU) versus non-ICU patients. Results: Eighty-one percent of patients were women. Pregnancy (34.8%), asthma (39.5%), diabetes mellitus (18.6%), and sickle cell (6.98%) were the most frequent comorbidities. In all, 91% had positive influenza nasopharyngeal direct antigen test, while 9% tested positive only by viral culture or real-time reverse transcriptase polymerase chain reaction (rRT-PCR); 14% required ICU admission; and 20.8% had infiltrate on chest X-ray. A trend toward greater incidence of ICU admission existed among patients with elevated SIG ( P = .08), however contrary to our prior studies in noninfluenza patients, an elevated SIG in the presence of normal AG and lactate measurements did not correlate with ICU admission. Conclusion: A high percentage of patients with H1N1 presented with underlying comorbid conditions including asthma and pregnancy. Traditional markers of pneumonia severity including CURB-65 score, Pneumonia Severity Index (PSI), serum lactate, and AG did not correlate with ICU admission in patients with H1N1. Strong ion gap effectively identified significant acid−base disturbances not identified by lactate or AG, however the trend of greater ICU admission rates among patients with elevated SIG did not reach statistical significance. Further study is needed to identify clinical tools to aid in risk-stratifying H1N1 patients.
Consumerism and the Crisis: Wither ‘the American Dream’?
Authors: Ivanova Maria N.
Published: February 2011

Starting with an inquiry into the socio-material foundations of American-style consumer capitalism as it emerged under Fordism and evolved under neoliberalism, this article seeks to outline the origins of the present economic crisis and the possible implications for the future of consumerism. The article argues that the ongoing crisis in the USA is not a regular cyclical downturn but signifies the end of finance-driven consumer capitalism as an accumulation regime whose key features can be summed up as debt-financed mass consumption of largely offshore produced goods and ‘wealth creation’ through rapidly appreciating asset values. The crisis qualifies as systemic in that various disproportionalities of the capitalist mode of production have resurfaced at the same time. While debt-driven consumer capitalism seems damaged to the extent of being no longer operable, the contours of a ‘post-consumerist’ future are not yet in sight.
The Effects of Exhaust Back Pressure on Conventional and Low-Temperature Diesel Combustion
Authors: Cong S , Garner C P , McTaggart-Cowan G P
Published: February 2011

Modern diesel engines are seeing increasing system and after-treatment complexity which can lead to significant increases in the exhaust back pressure (EBP). This increases the amount of trapped residuals, raising the charge temperature but reducing the oxygen concentration. In this work, these effects of the EBP on diesel engine performance and emissions under conventional and low-temperature diesel combustion (LTC) regimes were investigated.

Increasing the EBP resulted in higher pumping work for both combustion modes. While for conventional diesel combustion the effect of the EBP on combustion and emissions were not significant, for LTC the higher back pressures influenced the combustion and emissions formation processes. At low-load conditions, the increase in the charge temperature advanced combustion; at intermediate-load conditions, the reduction in the oxygen concentration delayed it. Smoke emissions were significantly reduced by a higher back pressure at intermediate-load conditions.
Analysis of the Vehicle Brake Judder Problem by Employing a Simplified Source—Path—Receiver Model
Authors: Duan C , Singh R
Published: February 2011

An analytical formulation of the brake judder problem caused by disc thickness variation is described by using a simplified source—path—receiver model. Eigenvalue analysis is first conducted to determine the transfer mechanism from the brake source to the steering-wheel receiver. Calculations show that the peak vibration levels of the steering wheel are seen when the rotational frequency of the tyre coincides with the resonant frequency of the transfer path; in this case, only the first-order disc thickness variation is considered. The effects of two key parameters, associated with the source and the path respectively, are analytically and computationally studied. Analysis suggests that the lower pad stiffness and/or the higher bushing stiffness should effectively reduce the vibration levels. Finally, a new vibration control concept is proposed that modulates the actuation pressure; it is based on an approximate solution for the angular displacement of the disc in the model developed here. Preliminary work indicates that this concept could be very effective in reducing the receiver vibration level without sacrificing the brake performance.
On-Board Measurements of Particulate Matter Emissions from a Passenger Train
Authors: Fridell E , Björk A , Ferm M , Ekberg A
Published: February 2011

A number of measurements of particle emission from railways are presented. The measurements featured a particle instrument mounted in a compartment under a Regina train. The particles were probed in a volume between the coaches. The measurements were done in two campaigns and provide information on how the particle emissions vary with driving patterns.

The measurements showed elevated particle concentrations when the train was running. Further, sharp peaks in the particle concentration were observed. It was noted that these peaks coincided with retardation of the train. However, there are also retardations where no peaks were observed. This can be explained from the two parallel breaking systems, one with regenerative breaking and one with mechanical breaks that are present on the Regina train. It is suggest that the observed peaks coincide with the use of the mechanical breaks. It was not possible to fully establish that increased particle concentration coincides with curvature of the rail, even though this was indicated in parts of the data.

The size-resolved data showed maxima for the smallest fraction (350 nm) for the number distribution.
Optimal design of metro automatic train operation speed profiles for reducing energy consumption
Authors: Domínguez M , Fernández A , Cucala A P , Lukaszewicz P
Published: February 2011

Trains equipped with automatic train operation (ATO) systems are operated between stations according to the speed commands they receive from balises. These commands define a particular speed profile and running time, with associated energy usage (consumption). The design of speed profiles usually takes into account running times and comfort criteria, but not energy consumption criteria. In this article, a computer-aided procedure for the selection of optimal speed profiles, including energy consumption, which does not have an effect on running times, is presented. To this end, the equations and algorithms that define the train motion and ATO control have been modelled and implemented in a very detailed simulator. This simulator includes four independent modules (ATO, motor, train dynamics, and energy consumption), an automatic generator of every possible profile and a graphical assistant for the selection of speed commands in accordance with decision theory techniques. The results have been compared with measured data in order to adjust and validate the simulator. The implementation of this new procedure in the Madrid underground has led to a 13 per cent of energy saving. As a result, the decision has been taken to redesign all the ATO speed profiles on this underground.
First Principles Analysis of Heat Exchanger Concepts and Designs for a Closed CO2 Brayton Cycle with Regeneration for a Lunar Fission to Surface Power System
Authors: Crawford D , Jerred N , Chang D , Jaiswal A , Reddy S , Howe S
Published: February 2011

The overall scope of this article is to develop and investigate different heat exchanger concepts for a closed CO2 Brayton power cycle with regeneration that is part of the fission to surface power system (FSPS) concept from NASA, designed to function as a lunar outpost. The heat exchangers investigated are designed with the goal of utilizing ‘off the shelf technology’ and a sub-goal to ensure the heat exchangers designed are integrated into the FSPS as a whole. The FSP system utilizes two streams as the hot and cold sources: 850K sodium and potassium eutectic (NaK) stream from a nuclear reactor and 375K water stream cooled in titanium radiator piping as the cold source, which must be kept as a liquid. The thermodynamics and heat exchanger parameters were modelled and calculated using chemical process simulation software. The power delivered is 10kW electric per power conversion unit. There are three heat exchangers investigated as possible options for the NaK—CO2 hot side heat exchanger. When compared with a shell-and-tube heat exchanger, the compact heat exchangers are a better choice because they provide a lower mass system and a smaller footprint.
Planetary Protection and Mars Sample Return
Authors: Bridges J C , Guest M
Published: February 2011

Mars sample return (MSR) mission planning requires a high level of planetary protection in order to break the chain of contact between Mars and the terrestrial biosphere. As a focus of MSR is the search for life, it is also imperative that a minimal amount of terrestrial contamination is taken to Mars on the mission. For these reasons, spacecraft cleaning of up to Viking levels will be needed, adding to the cost and complexity of the mission. Experience gained in Mars missions in the USA and Europe including and after Viking will be used. New technologies such as sample sealing in Mars orbit are also required. The recent identification of special regions on Mars where liquid water may have been present within the recent geological past has led to a revision of planetary protection constraints for missions such as MSR which might wish to visit them. Approximately 500g (five to eight samples) are envisaged in the first MSR within the 2020s. This requires a sample receiving facility to assess the threat to the terrestrial biosphere prior to analyses of the samples by the wider scientific community. This will be operated at biohazard level 4 — the highest level. Long-term curation of returned samples has planetary protection constraints but also challenges in maintaining the pristine nature of the samples as far as possible as they are moved from the oxidizing, reactive Mars surface to Earth.
Application of a magnetic dipole modelling approach to the problem of tracking a capsule endoscope
Authors: Wang X , Meng M Q-H
Published: February 2011

This paper shows that a small cylindrical permanent magnet enclosed inside a capsule can be used as a marker in endoscopy procedures. A modelling approach that treats the magnetic marker as a magnetic dipole is presented and an efficient, non-invasive, and low-cost localization method to track the capsule is proposed. A sensor array consisting of 16 magneto-resistive sensors is used to measure the magnetic field at multiple predetermined positions. The position and orientation parameters of the marker are calculated by minimizing the error between calculated and measured values of the field. The Levenberg-Marquardt optimization method is used to solve the inverse magnetic problem. Results are presented that show that the method is accurate and can be used for real-time tracking. The technique is applicable in environments that do not contain ferromagnetic materials as is the case for the human body.
Flexural and torsional rigidity of colonoscopes at room and body temperatures
Authors: Hellier D , Albermani F , Evans B , de Visser H , Adam C , Passenger J
Published: February 2011

A series of experiments have been conducted to determine the flexural and torsional rigidity of an Olympus colonoscope CF-140S and torsional rigidity of a Pentax colonoscope EC-3870 and the dependency of these properties on temperature and on the presence of loops. Along the length of the colonoscope, the flexural rigidity of the Olympus colonoscope varied between 260 and 400 Ncm2 and the torsional rigidity varied between 68 and 88 Ncm2/deg, with an average of 76 Ncm2/deg for tests involving 0.86 Nm of anticlockwise torque. Results show a significant decrease of 10 per cent in torsional rigidity between clockwise and anticlockwise torque. For the Pentax colonoscope flexural rigidity was not tested; its torsional rigidity varied between 34 and 76 Ncm2/deg, with an average of 46 Ncm2/deg for tests involving 0.43 Nm of anticlockwise torque. An increase in temperature of the Olympus colonoscope from 24 to 37 °C reduced the flexural rigidity by an average of 17 per cent and torsional rigidity by an average of 7 per cent. A right-handed loop caused a significant increase in flexural rigidity, but other looping configurations had no significant influence.
Determination of bone density distribution in proximal femur by using the 3D orthotropic bone adaptation model
Authors: Sarikanat M , Yildiz H
Published: February 2011

Most of the models developed and presented in the literature about bone remodelling assume bone as isotropic material. During this study, a structural model which has orthotropic bone properties is developed to simulate bone behaviour under mechanical loads. For a three-dimensional finite element modelling of proximal femoral bone, a computer code was written to investigate bone property changes owing to mechanical loads. The bone density distribution was determined after stress analysis was carried out in an iterative method. At every time step the bone properties were calculated depending on density change. Additionally, the effects of the bone remodelling parameters and sensors on numerical results were investigated. The most realistic bone density distribution in the proximal femur is obtained with strain energy density sensor. Generally initial bone density values do not have any effect on density distribution but at the low iteration numbers they may have some effects. Lastly, the density distribution of proximal femoral bone is more realistic for the dead zone size less than 0.35 and the stimulus value less than 2500.
Common theoretical basis for horizontal-axis wind and normal zero reaction gas turbines
Authors: Ntoko N-M
Published: February 2011

A relationship is obtained between the performance parameters of a blade ring of an axial wind turbine and corresponding ones of a normal stage of a zero reaction axial gas turbine. This has been achieved by recognizing and using mean axial velocity as a common parameter for defining the characteristic specific speed for the two types of turbines. Then on the basis of a constant value of the axial interference factor of 1/3, expressions for wind turbine power coefficient, tangential interference factor, and the relative outlet flow angle are obtained.
Availability (exergy) analysis in a thermal energy storage system with the phase change materials arranged in series
Authors: Keshavarz A , Mehrabian M A , Abolghasemi M , Mostafavi A
Published: February 2011

In this article, a thermal energy storage system is studied from the irreversibility point of view. The system consists of some phase change materials arranged in series. The phase change materials are located in the annular space between two concentric cylinders while the working fluid is flowing in the inner cylinder. Charging and discharging processes occur periodically. The conservation equations of energy for the working fluid and the phase change materials are solved numerically. The numerical results are validated when compared with available experimental results. The effect of different physical and geometrical factors on the irreversibility of the system is studied. The results show that the number of phase change materials and their arrangement have great influence on the irreversibility of the system. The temperature distribution inside the phase change materials affects the availability of the system. The proper arrangement of the phase change materials can reduce the irreversibility or increase the availability of the system.
Computational analysis of dynamic architecture
Authors: Chaudhry H N , Hughes B R
Published: February 2011

Dynamic architecture is a term devised for a new generation of off-grid high-rise structures that rotate. The proposed structures contain wind turbines between floors which are used to generate the power to rotate the floors and for consumption by residents. This study analyses the capabilities of this system in comparison with the standard vertical arrangement of a wind turbine. A performance analysis of the WinWind 3.0 MW wind turbine is performed. Data from the Dubai Meteorological Services were collected and analysed in conjunction with the performance analysis of this wind turbine. Furthermore computational fluid dynamic modelling was carried out and analysed for comparison. The results demonstrated that the standard horizontal orientation of a wind turbine yielded 80 per cent more power. The proposed horizontal orientation requires 46 turbines to generate enough power to sustain the consumption of the building.
Energy, economic, and environmental analysis of combined heating and power-organic Rankine cycle and combined cooling, heating, and power-organic Rankine cycle systems
Authors: Hueffed A K , Mago P J
Published: February 2011

Combined heating and power (CHP) and combined cooling, heating, and power (CCHP) systems generate electricity and usable heat on-site from one fuel source while organic Rankine cycles (ORC) generate power from low-temperature heat sources. During the operation of CHP and CCHP systems, there are many instances when the recovered exhaust heat is greater than the required thermal load of the building. In these situations, an ORC can be used to capture the excess heat in order to produce additional electricity. Therefore, combining an ORC system with a CHP system (CHP-ORC) or a CCHP system (CCHP-ORC) can further increase the fuel utilization of the system, thereby reducing the operational costs, primary energy consumption (PEC), and carbon dioxide emissions (CDE). This article examines the economic, energetic, and environmental performance of CHP-ORC and CCHP-ORC systems under the operational strategies of follow the electric load (FEL) and follow the electric load with the option of turning off (FEL/OFF) for the city of Boulder, Colorado. Their performance is compared to a stand-alone CHP and CCHP system, respectively, between systems, and to a reference building. Results show that under the FEL operation, the addition of an ORC to either the CHP or CCHP system lowered the operational costs, PEC, and CDE by about 12 per cent, 13 per cent, and 17 per cent, respectively, from the standalone system. In addition, only when the systems operate FEL/OFF strategy minimizing cost or PEC, the cost and PEC could be reduced below the levels of the reference building.
Research and development of a semi-hermetic reciprocating compressor for transcritical CO2 refrigeration cycle
Authors: Ma Y , Zhang B , Hwang Y H , Peng X Y , Xing Z W
Published: February 2011

A semi-hermetic reciprocating compressor was designed and developed for the transcritical carbon dioxide (CO2) refrigeration cycle. In addition, a mathematical model was established to simulate the thermodynamic process in this transcritical CO2 compressor. The internal leakage, heat transfer, and flows through the suction/discharge valves together with the valve motion were taken into account in the model. In order to evaluate the overall performance of the developed compressor, a test rig was built to measure the volumetric efficiency, isentropic efficiency, and coefficient of performance (COP), and also recorded the pressure—volume diagram. The calculated indicated power deviated by 4.16 per cent from the measured one, and the maximum deviations of the isentropic and volumetric efficiencies were −2.86 per cent and 4.87 per cent, respectively. Both the calculated and measured data showed that the compressor had a cooling COP of 2.0—3.2. As the pressure ratio increased from 2.3 to 3.5, the volumetric and isentropic efficiencies ranged from 0.70 to 0.86 and from 0.62 to 0.66, respectively. The recorded p— V diagram indicated that the power losses associated with the suction and discharge processes accounted for 4.6 per cent and 6.8 per cent of the total indicated power, respectively. The validated model can be used to investigate the thermodynamic process of the reciprocating CO2 compressor with the aim of enhancing the compressor efficiency.
Depilatory Agents intoxication and factors contributing to its mortality: A 9-year review
Authors: Farzaneh Esmaeil , Mostafazadeh Babak , Zamani Nasim , Eskandari Armen , Emamhadi Mohammadali
Published: February 2011

Poisoning with depilatory agents is a rather uncommon entity in western countries. In this study, we describe poisoning with a corrosive arsenic-based depilatory agent (CABD) and factors related to its mortality in a poisoning center in Tehran. In a retrospective study, the medical records of all patients with CABD intoxication who attended the emergency ward of Loghman-Hakim hospital, the only poisoning center in Tehran, over a 9-year period between 2000 and 2009 were reviewed. The majority of patients were men (78.7%, n = 122 vs. women: 21.3%, n = 33). The mean age was 35.55 ± 16.68 years. Mean time of arrival to hospital was 3.63 hours (SD = 4.07). The mortality rate was 5.8% and increased significantly with higher amounts of ingestion and delay in arrival to hospital. CABD poisoning may be lethal if not treated promptly and correctly. Restriction or, if not practical, reduction of harmful components of this substance should be considered.
Capsaicin may induce breast cancer cell death through apoptosis-inducing factor involving mitochondrial dysfunction
Authors: Chang HC , Chen ST , Chien SY , Kuo SJ , Tsai HT , Chen DR
Published: February 2011

The majority of breast cancer patients are resistant to chemotherapy or radiotherapy due to the down-regulation or lack of caspase-3 expression. Capsaicin was found to inhibit cancer cell growth in caspase-3-deficient human breast cancer cells. This study aimed to investigate the growth-inhibitive effect of capsaicin and its mechanisms in human breast cancer cell lines, MCF-7 and BT-20. The results showed that cell viability decreased in a dose-dependent manner in both the caspase-3-deficient and non-deficient cells through inducing cell apoptosis and arresting the cell cycle in the S phase. Capsaicin significantly decreased mitochondria membrane potential, induced the cleavage of PARP-1, and decreased procaspase-7 expression in both cells. Apoptosis-inducing factor (AIF) was distinctly released from mitochondria and translocated into the cytoplasm and nucleus in MCF-7 cells (52.9%), but not in BT-20 cells (2%) after treatment with 200 μM of capsaicin for 24 hours. Capsaicin inhibited breast cancer cell growth through inducing cell apoptosis and cell cycle arrest in the S phase. This apoptotic effect could be induced through the mitochondrial pathway, and PARP-1 subsequently cleaved by activation of caspase-7. The application of capsaicin in clinical therapy could be useful for breast cancer patients.
Lipid patterns in the saliva of smoking young adults
Authors: Palmerini CA , Saccardi C , Ferracci F , Arienti S
Published: February 2011

Salivary lipids are important for the maintenance of oral cavity health. Elevated salivary lipid levels are associated with an increase of caries incidence, plaque development, calculus formation and periodontal disease. However, the regulation of lipid salivary levels is scarcely known. Cigarette smoke is considered a risk factor for oral cavity diseases. We study how cigarette smoke may affect the secretion of salivary lipids. To this purpose, we determine the salivary levels of cholesterol and of glycerolipids in saliva sampled from smokers and non-smokers at various times of day. We observe an increase of glycerophospholipid and a decrease of cholesterol levels in the smokers’ saliva collected at 10 p.m. On the other hand, unsaturated fatty acids in chief phospholipids of saliva are lower in smokers at 7 a.m. Therefore, for the first time, we demonstrate that cigarette smoke induces variations of saliva lipid pattern in young people even moderately smoking.
Sodium sulfite aggravated allergic sensitization and airway inflammation in mite allergen sensitized BALB/c mice
Authors: Lin Heng-Kuei , Tsai Jaw-Ji , Wen Mei-Chin , Tsai Ming-Chin , Chen Ciao-Jin , Fu Lin-Shien
Published: February 2011

Sulfur dioxide is a typical air pollutant. Sulfite, which is formed at the bronchial mucosa from inhaled sulfur dioxide, might play a role in the exacerbation of asthma. In this study, we investigated the effects of sodium sulfite and its interaction with a house dust mite ( Dermatophagoides pteronyssinus, Der p) on allergic sensitization and airway inflammation. BALB/c mice were divided into four groups: control ( n = 10), mite intranasal (mIN, n = 12), sodium sulfite intranasal (sIN, n = 12) and mIN + sIN ( n = 12). In non-control groups, the mice were sensitized on day 8 and day 15 with mite allergen subcutaneously. Mite allergen was then administrated intranasally from day 15 to day 22 in mIN and mIN+sIN groups. Sodium sulfite was administrated in sIN and mIN + sIN groups intranasally from day 1 to day 22. Plasma Der p-specific IgE, IgG2a, lung histopathology and cytokine levels (IL-5 and IFN-γ) were analyzed. In comparison between mIN (or sIN) and mIN + sIN group, Der p-specific IgE levels were significantly higher in mIN + sIN group ( p < 0.01). Besides, Der p-specific IgG2a level was significantly lower in mIN + sIN group than mIN (or sIN) group ( p < 0.01). The peribronchiolar, alveolar and total inflammatory scores were increased in the mIN + sIN group comparing with the control group ( p < 0.05, p < 0.01, p < 0.01, respectively). Lung supernatant in mIN + sIN group has higher IL-5/IFN-γ ratio than control, mIN or sIN group (all p < 0.05). Our study concluded sodium sulfite may enhance allergic sensitization as well as airway inflammation in mite allergen sensitized BALB/c mice.