bluuebunny/crossref_metadata_2025 huggingface dataset:
Using localised weather files to assess overheating in naturally ventilated offices within London's urban heat island
Authors: Demanuele C , Mavrogianni A , Davies M , Kolokotroni M , Rajapaksha I
Published: September 2011

Urban environments typically experience increased average air temperatures compared to surrounding rural areas – a phenomenon referred to as the Urban Heat Island (UHI). The impact of the UHI on comfort in naturally ventilated buildings is the main focus of this article. The overheating risk in urban buildings is likely to be exacerbated in the future as a result of the combined effect of the UHI and climate change.

In the design of such buildings in London, the usual current practice is to view the use of one generic weather file as being adequate to represent external temperatures. However, the work reported here demonstrates that there is a considerable difference between the overheating performance of a standard building at different sites within London. This implies, for example, that a building may wrongly pass or fail criteria used to demonstrate compliance with building regulations as a result of an inappropriate generic weather file being used. The work thus has important policy implications.

Practical application: The Greater London Authority has recently developed, with the Chartered Institute of Building Services Engineers, guidance for developers to address the risk of overheating in buildings via the provision of weather files for London relating to three zones. While such an initiative is welcomed, it may be that a weather file tailored to the building location would be preferable. Of course, this would add further complexity to the process and a view would have to be taken as the viability of such an approach. The work presented in this article, however, suggests that serious consideration should be given to the use of tailored weather data for regulatory purposes.
An analysis of heat insulation efficiency of building outer skins used for green building
Authors: Hou W-S , Chuang T-F , Hsieh E-C , Chang Y-H
Published: September 2011

In general, the poor thermal insulation of building materials usually causes elevated room temperature, which not only reduces the comfort of the environment but also adds extra loading to the air conditioner. The objective of this study is to investigate the heat insulation efficiencies of building outer skins used for green building. A total of 25 types of multi-layer cladding materials and 9 types of single-layer skin materials made in Taiwan along with 4 types of overseas multi-layer skin materials were tested using the hot box method (HBM). The above data were then adopted to calculate the heat-insulation ability, vapor transmission volume and heat gain cooling load. Besides, the costs of the above materials were also collected to provide useful information for green building industry to select the most proper skin materials in considering both the material performance and costs. The analysis results suggest that the ‘k’ group (paint-baked metal plate + 2” 100 k rock wool + paint-baked metal plate) exhibits the best heat-insulating capacity, which is 67.0%. However, Item 15 (colour corrugated steel plate + conventional steel bearing plate + calcium silicate board) presents the smallest moisture-permeable amount at 0.001 g/h. Besides, Item ‘13’ exhibits the smallest cooling load, which is 1.8 W. From the above, it is shown that superior heat-insulating performance does not necessarily mean better moisture permeability resistance. The skin material which presents superior moisture permeability resistance does not always present a higher cooling load. For this reason, the appropriate skin materials should be selected by matching with the climatic environment where the building is located. Moreover, the decrement of CO2 emissions caused by transportation is also another key point which the green building industry should consider.

Practical application: The objectives of this research are to investigate the heat insulation efficiencies of building outer skins used in the green buildings. The heat capacity, moisture-permeable resistance, solar heat gain cooling load and costs of the building outer skins frequently used in Taiwan have been calculated and collected in this study. Therefore, the engineers and building industry can choose the most suitable materials with the help of the above information.
Combination of Voice Therapy and Antireflux Therapy Rapidly Recovers Voice‐Related Symptoms in Laryngopharyngeal Reflux Patients
Authors: Park Jun‐Ook , Shim Mi‐Ran , Hwang Yeon‐Shin , Cho Kwang‐Jae , Joo Young‐Hoon , Cho Jung‐Hae , Nam Inn‐Chul , Kim Min‐Sik , Sun Dong‐Il
Published: September 2011

Objective

Patients with laryngopharyngeal reflux frequently experience voice‐related symptoms. This study was designed to investigate the effectiveness of combined voice and medical therapy in comparison with medical therapy alone in the improvement of voice‐related symptoms and parameters in patients with laryngopharyngeal reflux.

Study Design

Concurrent nonrandomized comparative trial.

Setting

Otolaryngology department at a university hospital.

Subjects and Methods

In this prospective study, 100 patients diagnosed with laryngopharyngeal reflux with voice symptoms were divided into 2 groups: 50 patients were treated with medication alone, and 50 were treated with medication plus voice therapy. The following data were recorded before treatment and at 1, 2, and 3 months posttreatment: reflux symptom index (RSI), reflux finding score (RFS), voice handicap index (VHI), perceptual analysis, and acoustic analysis. The numbers of patients showing clinically significant reductions in these parameters were compared between groups using the following cutoff values: change in RSI ≥5, change in RFS ≥3, change in VHI ≥15, and change in grade, roughness, breathiness, asthenia, and strain scale (GRBAS) ≥1.

Results

Significantly more patients in the study group showed a clinically significant change in RSI, VHI, and GRBAS score at the 1‐, 2‐, and 3‐month follow‐up evaluations. No clinically significant change in RFS was achieved in either group at 1 or 2 months, but a significantly greater change was achieved in the study group at 3 months.

Conclusions

Voice therapy may help to restore reversible mucosal change secondary to acidic reflux, inducing rapid resolution of symptoms and shortening of the treatment period.
Vocabulary intervention for school-age children with language impairment: A review of evidence and good practice
Authors: Steele Sara C , Mills Monique T
Published: September 2011

The purpose of this article is to provide evidence to support direct vocabulary intervention practices for primary school-age children with language impairment (LI). A rationale for providing direct vocabulary intervention for children with LI is outlined by reviewing typical and atypical vocabulary acquisition, evidence of instructional strategies from research in mainstream and special education is summarized, and suggestions for vocabulary intervention activities that facilitate deep word knowledge are provided. Suggestions for choosing appropriate vocabulary, using strategies during direct intervention, and conducting activities that increase depth of vocabulary knowledge, are included.
Colourful semantics: A clinical investigation
Authors: Bolderson Sarah , Dosanjh Christine , Milligan Claudine , Pring Tim , Chiat Shula
Published: September 2011

Children with language difficulties often omit verbs and grammatical elements and fail to complete sentences. Bryan (1997) described ‘colourful semantics’, a therapy she used to treat a 5-year-old boy. The therapy uses colour coding to highlight the predicate argument structure of sentences. This study further tested the therapy’s effectiveness by assessing the progress of six 5- and 6-year-olds receiving it under clinical conditions. The children were assessed on the Renfrew Action Picture Test (RAPT), the Bus Story, the Test of the Reception of Grammar (TROG) and an informal verb assessment. They were assessed again after a 9-week baseline without therapy and then treated twice weekly for 8 weeks after which a final assessment was carried out. A clinician who did not know the children conducted the second and third assessments. RAPT information and grammar scores and the Bus Story information and mean sentence length scores all improved during therapy but not in the baseline. These results obtained under clinical conditions are encouraging and warrant a larger study of this approach.
Does colour affect the quality or quantity of children’s stories elicited by pictures?
Authors: Schneider Phyillis , Rivard Reane , Debreuil Buffy
Published: September 2011

The current study investigated the effect of colour vs. black-and-white pictures on the stories children told using the pictures as stimuli. Participants were 22 preschool children aged 4—6 (M = 59.98, SD = 7.52) attending day-care centres in a Western Canadian city. Two story sets of five pictures each, depicting stories with similar structure, were used as stimuli. Two versions of each story were made, one in colour and one in black and white. Each child was presented with one of the stories in colour and the other in black and white; versions and stories were counterbalanced across children. Stories were analysed for differences in content using story grammar, in amount using total number of words used in telling the story, and in vocabulary variety using number of different words used. Children were also asked which of the two stories they had preferred and why they preferred that story. Results indicated that stories children told did not differ on any of the variables; children told stories that were similar in content, length, and word variety regardless of whether the pictures used to elicit stories were in colour or black and white. When asked which story they preferred, roughly equal numbers of children expressed a preference for each version; when asked why that story was preferred, only four children ascribed it to colour, while the majority of children gave content-related reasons for their preference. We conclude that colour or lack thereof in picture stimuli does not appear to affect stories told by preschool children who are typically developing.
Dancing to two tunes: Multi-entity roles in the family business succession process
Authors: Lam Wing
Published: September 2011

While some studies of family business focus on the succession process, very few have tried to understand it as an interactive, dynamic social process. The multi-entity roles that family business members play simultaneously during the social process have been largely ignored. The findings of this longitudinal ethnographic study highlight the inconsistency between the expressed attitudes, perceptions, plans and actual behaviours of family business members. In-depth discourse analysis and observation shed light on their underlying values, needs and hidden agendas, which have a major impact on the operation, success or failure of the business. This study has major implications for business founders and successors to understand their own roles in the succession process. It also has practical value for professional managers to understand the challenges and opportunities in the process of family business succession. It is important for policymakers to understand why family business succession fails, so that appropriate public policies can be introduced to support family businesses.
State-directed political assassination in Israel: A political hypothesis
Authors: Gazit Nir , Brym Robert J
Published: September 2011

Extant theories explain reasonably well why the Israeli state exercises a given level of violence against substate actors. Based on economic or sociological models of human action, these theories attribute the level of state violence, respectively, to the narrow cost-benefit calculations of state officials or the institutionally embedded norms that govern their deliberations. The strength of such theories notwithstanding, this article argues that they fail to account for the willingness of Israeli officials to order the assassination of high-ranking political opponents during the second intifada, or Palestinian uprising against Israel. This article’s analysis of published sources concerning the assassination of Hamas leaders Ahmed Yassin and Ismail Abu Shanab and of interviews with 74 Israeli counterterrorist experts suggests that the decision to engage in state-directed political assassination in the period 2000–5 was based less on narrow calculations and institutionally specific norms than on identifiable political contingencies. Specifically, the second intifada appears to have led many Israeli decision-makers to favour creating chaos in the Palestinian political system, a goal that was well served by the policy of political assassination. The policy’s effect was to forestall the founding of a viable, independent Palestinian state.
Privacy pragmatism and streetscape video surveillance in Canada
Authors: Hier Sean P , Walby Kevin
Published: September 2011

This article contributes to international debates about public-area streetscape video surveillance by assessing the Canadian policy context. Based on findings from an ongoing empirical investigation, the authors argue that Canada’s pragmatic policy framework enables surveillance advocates and adversaries to selectively endorse privacy protection principles institutionalized in best practice protocols. The authors explain their findings in relation to the international literature on video surveillance policy diffusion and privacy.
What are cancer patients’ experiences and preferences for the provision of written information in the palliative care setting? A focus group study
Authors: Tomlinson Kim , Barker Stephanie , Soden Katie
Published: September 2011

Background:

Whilst there is a wide range of literature pertaining to the need for excellent verbal communication within the palliative care setting, there is a paucity of research designed to identify the written informational needs of such patients.

Aim:

To identify the experiences and wishes of patients known to a specialist palliative care service in England with regards to written information. We considered both generalizable written information (such as leaflets, books and internet resources) as well as individualized information (for example, copies of letters given to patients).

Design:

Five focus group discussions were recorded and transcribed for analysis.

Setting/participants:

The focus groups took place at one specialist palliative care unit in England. Twenty-two patients with cancer over the age of 18 years were recruited.

Results:

Inductive, realist thematic analysis of the data set was performed. Themes have been broadly categorized into three main areas: (i) patients’ views on the role of written information, (ii) their experiences of written information in different formats, and (iii) their thoughts on what written information they would most value.

Conclusions:

Written information needs for this patient group vary greatly, sometimes in ways which can be predicted. Using a patient-centred approach to elicit information around an individual’s coping strategies, desire for knowledge and empowerment may be helpful. The data supports a proactive approach to making available (to those who want them) clear, concise and attractive leaflets.
Group Climate and Empathy in a Sample of Incarcerated Boys
Authors: van der Helm G. H. P. , Stams G. J. J. M. , van der Stel J. C. , van Langen M. A. M. , van der Laan P. H.
Published: September 2011

This study examined the influence of group climate on empathy in a Dutch youth correctional facility in a sample of 59 incarcerated delinquent boys. Higher levels of empathy have been shown to be associated with less delinquent and more prosocial behaviour and may therefore be vital for successful rehabilitation and recidivism reduction. Although empathy was originally considered to be a trait, recent neurobiological research has shown that empathy has state-like properties in that levels of empathy change in response to the social environment. This study showed that differences in group climate were associated with cognitive empathy in juvenile delinquents but not with affective empathy. It is speculated that inmates’ state-depressive feelings and anxiety could diminish the effects of prison group climate on affective empathy. The discussion focuses on group dynamics in youth correctional facilities. A positive prison group climate in a youth correctional facility could turn out to be a major factor contributing to effectiveness of secure institutional treatment.
A Simple Evaluation of Anterior Cruciate Ligament Femoral Tunnel Position
Authors: Illingworth Kenneth David , Hensler Daniel , Working Zachary Mark , Macalena Jeffrey Alexander , Tashman Scott , Fu Freddie H.
Published: September 2011

Background: Postoperative determination of tunnel position after anterior cruciate ligament (ACL) reconstruction can be challenging.

Hypothesis: The femoral tunnel angle and inclination angle are reliable methods for evaluating tunnel position after ACL reconstruction while aiding in determining whether an ACL reconstruction falls outside an anatomic range as defined on 3-dimensional (3D) computed tomography (CT).

Study Design: Cohort study (diagnosis); Level of evidence, 3.

Methods: Fifty patients were included who received single-bundle ACL reconstructions with postoperative flexion weightbearing radiographs, magnetic resonance imaging (MRI), and CT scans. Femoral tunnel angles were determined from posterior-to-anterior postoperative radiographs, and inclination angles were determined from sagittal MRI. The ACL reconstructions were grouped by surgical technique, transtibial (TT) or tibial tunnel independent (TTI), and as either falling inside or outside an anatomic range on 3D CT.

Results: Patients with tunnel positions within an anatomic range, as previously defined, had a larger femoral tunnel angle (39.3° ± 4.2°) and smaller inclination angle (49.5° ± 2.7°) than patients who fell outside an anatomic range (17.2° ± 12.5° and 62.3° ± 7.8°, respectively) ( P < .001). Patients in the TTI group had a larger femoral tunnel angle (37.6° ± 9.30°) and smaller inclination angle (51.8° ± 6.5°) than those in the TT group (14.2° ± 9.3° and 63.5° ± 7.2°, respectively) ( P < .001). Posterior-to-anterior femoral tunnel position was negatively correlated with femoral tunnel angle ( P < .001, r = .78) and positively correlated with inclination angle ( P < .001, r = .74). Based on a receiver operating characteristic (ROC) curve, a femoral tunnel angle of 32.7° (100% sensitivity and 85% specificity) and inclination angle of 55° (100% sensitivity and 87.5% specificity) were determined to distinguish ACL reconstructions that fell either within or outside an anatomic range on 3D CT.

Conclusion: Femoral tunnel angle and inclination angle can be reliably determined from both posterior-to-anterior radiographs and sagittal MRI and provide a useful metric for characterizing femoral tunnel position.
In-Shoe Plantar Pressures Within Ankle-Foot Orthoses
Authors: Kearney Rebecca S. , Lamb Sarah E. , Achten Juul , Parsons Nicholas R. , Costa Matthew L.
Published: September 2011

Background: Advances in the management of Achilles tendon rupture have led to the development of immediate weightbearing protocols. These vary regarding which ankle-foot orthoses (AFOs) are used and the number of inserted heel wedges used within them.

Purpose: This study was conducted to evaluate plantar pressure measurements and temporal gait parameters within different AFOs, using different numbers of heel wedges.

Study Design: Controlled laboratory study.

Methods: Fifteen healthy participants were evaluated using 3 different AFOs, with 4 different levels of inserted heel wedges. Therefore, a total of 12 conditions were evaluated, in a sequence that was randomly allocated to each participant. Pressure and temporal gait parameters were measured using an in-shoe F-Scan pressure system, and range of movement was measured using an electrogoniometer.

Results: Ankle-foot orthoses that were restrictive in design, combined with a higher number of inserted heel wedges, reduced forefoot pressures, increased heel pressures, and decreased the amount of time spent in the terminal stance and preswing phase of the gait cycle ( P = .029, .002, and .001).

Conclusion: The choice of AFO design and the number of inserted heel wedges have a significant effect on plantar pressure measurements and temporal gait parameters. The implications of these changes need to be applied to the clinical management of acute Achilles tendon ruptures. This clinical management requires a balance between protected weightbearing and functional loading, requiring further research within a clinical context.

Clinical Relevance: The biomechanical data from this research imply that a carbon-fiber AFO, with 1 heel raise, protects against excessive dorsiflexion while facilitating the restoration of near-normal gait parameters. This could lead to an accelerated return to function, avoiding the effects of disuse atrophy. This is in contrast to the rigid rocker-bottom AFO design with a greater number of heel-wedge inserts. However, research within a clinical context would be required to ascertain if these biomechanical advantages translate into a functional benefit for patients. The results should also be considered in relation to the amount of force a healing Achilles tendon can withstand.
Biomechanical Evaluation of Knee Joint Laxities and Graft Forces After Anterior Cruciate Ligament Reconstruction by Anteromedial Portal, Outside-In, and Transtibial Techniques
Authors: Sim Jae Ang , Gadikota Hemanth R. , Li Jing-Sheng , Li Guoan , Gill Thomas J.
Published: September 2011

Background: Recently, anatomic anterior cruciate ligament (ACL) reconstruction is emphasized to improve joint laxity and to potentially avert initiation of cartilage degeneration. There is a paucity of information on the efficacy of ACL reconstructions by currently practiced tunnel creation techniques in restoring normal joint laxity.

Study Design: Controlled laboratory study.

Hypothesis: Anterior cruciate ligament reconstruction by the anteromedial (AM) portal technique, outside-in (OI) technique, and modified transtibial (TT) technique can equally restore the normal knee joint laxity and ACL forces.

Methods: Eight fresh-frozen human cadaveric knee specimens were tested using a robotic testing system under an anterior tibial load (134 N) at 0°, 30°, 60°, and 90° of flexion and combined torques (10-N·m valgus and 5-N·m internal tibial torques) at 0° and 30° of flexion. Knee joint kinematics, ACL, and ACL graft forces were measured in each knee specimen under 5 different conditions (ACL-intact knee, ACL-deficient knee, ACL-reconstructed knee by AM portal technique, ACL-reconstructed knee by OI technique, and ACL-reconstructed knee by TT technique).

Results: Under anterior tibial load, no significant difference was observed between the 3 reconstructions in terms of restoring anterior tibial translation ( P > .05). However, none of the 3 ACL reconstruction techniques could completely restore the normal anterior tibial translations ( P < .05). Under combined tibial torques, both AM portal and OI techniques closely restored the normal knee anterior tibial translation ( P > .05) at 0° of flexion but could not do so at 30° of flexion ( P < .05). The ACL reconstruction by the TT technique was unable to restore normal anterior tibial translations at both 0° and 30° of flexion under combined tibial torques ( P < .05). Forces experienced by the ACL grafts in the 3 reconstruction techniques were lower than those experienced by normal ACL under both the loading conditions.

Conclusion: Anterior cruciate ligament reconstructions by AM portal, OI, and modified TT techniques are biomechanically comparable with each other in restoring normal knee joint laxity and in situ ACL forces.

Clinical Relevance: Anterior cruciate ligament reconstructions by AM portal, OI, and modified TT techniques result in similar knee joint laxities. Technical perils and pearls should be carefully considered before choosing a tunnel creating technique.
Concepts of Infidelity Among African American Emerging Adults
Authors: Eyre Stephen L. , Flythe Michelle , Hoffman Valerie , Fraser Ashley E.
Published: September 2011

In this study, we used an exploratory methodology to determine what cultural models African American emerging adults use to understand infidelity/cheating. Cultural models are defined as “cognitive schema[s] that [are] intersubjectively shared by a social group” (D’Andrade, 1987, p. 112). We interviewed 144 participants ages 19-22 from three geographically distal sites. Qualitative analysis was conducted using NUDIST and In Vivo Analysis, a form of Grounded Theory. Among those in a main (dyadic) relationship, 37% of females and 57% of males stated they had been unfaithful to their main partner during the past month. We identify five cultural models defining 1) the nature of infidelity, 2) reasons for infidelity, 3) techniques for managing side (extra-dyadic) partners, 4) means of investigating suspected infidelity, and 5) condom use in main and side relationships. Our findings suggest that stressing condom use in side partner relationships may be a particularly effective means of HIV/STI prevention in this high-risk population.
Immersing Students in the Culture of Disability Through Service Learning
Authors: Santos Rosa Milagros , Ruppar Andrea L. , Jeans Laurie M.
Published: September 2011

This article provides a description of service learning implemented in an introductory special education course focused on the culture of disability. Collaborating with liaisons from five community service organizations, students provided services to individuals with disabilities in a variety of projects across two semesters. Communication and collaboration at all phases of the project were essential to ensuring that service learning was salient to the organization and meaningful to the students. The students presented a final report about their service-learning project and individually submitted a paper reflecting on their experience. Pre- and post-ratings of students’ perspectives of the culture of disability were gathered. Students reported increased knowledge related to course content, and all participants reported satisfaction with the projects. Strategies that proved successful in assisting students accomplish their project goals are discussed. Recommendations for the use of service learning in personnel preparation of future special educators are presented.
Special Educators and Nonsuicidal Self-Injurious Behavior
Authors: Jasper Andrea D. , Morris Carrie Wachter
Published: September 2011

Nonsuicidal self-injurious behavior (NSSIB) is one of the most perplexing and challenging behaviors special educators come across in their schools. Thus, there is a need for special educators to be equipped with information regarding NSSIB to help identify students with disabilities who engage in these behaviors and provide them with appropriate support or referrals. This study examined the effectiveness of training received by 390 special educators on NSSIB and their self-efficacy regarding the training. Results revealed that although many special educators serve students who engage in self-injurious behaviors, many did not receive training on how to implement strategies for students who self-injure. Those special educators who received training were more confident in their abilities to work with students who self-injured compared with those special educators who did not receive training. Implications, limitations, and future research areas are discussed.
Prediction of ovalling frequency for FRP chimney liners with circumferential stiffeners
Authors: Li Shidong , Eisenman Jeffrey D , Mikulec Darryl
Published: September 2011

ASTM D 5364 requires that the lowest ovalling frequency of a fiberglass reinforced plastic chimney liner shall not be less than 2 Hz. From engineering practices and numerical experiments, the authors find that the frequency calculated in accordance with ASTM D 5364 deviates considerably from results using finite element analysis (FEA). A modified equation has been proposed in this article to better evaluate the lowest ovalling frequency for FRP chimney liners.
Surface morphology, mechanical and tribological properties of blended deproteinized natural and polyisoprene rubbers
Authors: Nasir RM , El-Tayeb NSM
Published: September 2011

The morphology, and mechanical and tribological properties of deproteinized natural rubber with constant viscosity (DPNR) and synthetic cis-1, 4 polyisoprene vulcanizates (IR2200) using ISAF220 carbon black (CB) blends were studied in various ratios: 100/0, 75/25, 50/50, 25/75 and 0/100. Results for different operating test conditions under applied normal load, sliding speed and sliding distance were analyzed. The experimental results showed that the addition of CB (30 phr.) has significantly affected the wear and frictional performance of both DPNR-CV and IR2200 by decreasing the abrasion weight loss by more than 80% compared with the unfilled DPNR and IR2200. Adding 30 phr CB decreases the abrasion weight loss to more than 70%. The surface topography of micro-scales abrasion was characterized by scanning electron microscopy (SEM). Using SEM micrographics, the influence of blend ratios on wear mechanisms and spacing imprinted abrasion patterns was highlighted.
Banana fiber-reinforced polypropylene nanocomposites: Effect of fiber treatment on mechanical, thermal, and dynamic-mechanical properties
Authors: Biswal Manoranjan , Mohanty Smita , Nayak Sanjay K
Published: September 2011

Banana fiber-reinforced nanocomposites were fabricated by melt mixing in a twin-screw extruder followed by compression molding in this study. Maleic anhydride polypropylene copolymer (MA-g-PP) was used as a compatibilizer to increase the compatibility between the PP matrix, clay, and banana fiber to enhance exfoliation of organoclay and dispersion of fibers into the polymer matrix. Variation in mechanical, thermal, and physico-mechanical properties with the addition of banana fiber into the PP nanocomposites was investigated. It was observed that presence 3 wt% of nanoclay and 5 wt% MA-g-PP within PP matrix results in an increase in tensile and flexural strengths by 41.3%, and 45.6%, respectively, compared with virgin PP due to the high aspect ratio of clay stacks in the fully exfoliated nanocomposites. Further, incorporation of 30 wt% banana fiber in PP nanocomposites system increases the tensile and flexural strengths to the tune of 27.1%, and 15.8%, respectively. The morphology of fiber-reinforced PP nanocomposites has been examined using scanning and transmission electron microscopies. Significant enhancement in thermal stability of nanocomposites was also observed due to the presence of nanoclay under thermogravimetric analysis. Dynamic mechanical analysis tests revealed an increase in storage modulus ( E′) and damping factor (tan δ), conforming the strong interaction between nanoclay/banana fiber and MA-g-PP in the fiber-reinforced nanocomposites systems.
On the numerical simulation of injection molding processes with integrated textile fiber reinforcements
Authors: Niedziela Dariusz , Tröltzsch Jürgen , Latz Arnulf , Kroll Lothar
Published: September 2011

In the present article, the polymer melt impregnation of textile fiber reinforcements in an injection molding process is explored theoretically and experimentally. Simplifying the numerical simulation of the thermoplastic melt flow behavior a specific mold with integrated single-glass fiber bundle was developed and used for experimental fill studies with thermoplastic melt. The polymer melt impregnation of the fiber bundle in the injection molding process is modeled and calculated with Complex Rheology Polymer Solver (CoRheoPol), a simulation tool developed at Fraunhofer Institut fŭr Techno- und Wirtschaftsmathematik by the present authors. Navier-Stokes and Navier-Stokes-Brinkman equations are used to describe the melt flow in a pure fluid region and porous media, considering the non-Newtonian flow behavior of thermoplastic melts. Experimental and numerical results are compared determining the filling fronts and fiber impregnation of the injection molded test samples. A clear relationship between the degree of impregnation, verified by magnified photomicrograph, and the position of flow front can be detected. A good correlation of simulated and experimental flow fronts against the degree of filling of the mold is observed too. The differences in macroscopic flow behavior between the cavity with and without an integrated fiber bundle with respect to the impregnation process can be simulated with high accuracy.
Assessing Espoused Goals in Private Family Firms Using Content Analysis
Authors: McKenny Aaron F. , Short Jeremy C. , Zachary Miles A. , Payne G.Tyge
Published: September 2011

Understanding how private family firms gauge performance is of great interest to family business scholars. Unfortunately, finding comparable data to understand differences in the performance of such firms is challenging. This study draws from the organizational identity literature to show how private family firms communicate different goals in publicly available organizational narratives. The authors illustrate a process using content analysis that allows family business scholars to create a comparative data set that captures both normative and utilitarian goals using website and press release narratives from a sample of Australian firms.
Revolution, Interrupted: Gender and Microfinance in Nicaragua
Authors: Haase Dwight
Published: September 2011

Now reaching over 100 million families, the burgeoning microcredit movement has come to play a dominant role in the international development agenda. This is especially true in Nicaragua, where microcredit has supplanted the Sandinistas’ more radical approaches to poverty alleviation and women’s empowerment. Survey and focus group data from borrowers with seven prominent Nicaraguan microfinance institutions show that women benefit less than men from microcredit because they get smaller loans and they invest those loans in less lucrative businesses. Also, these women are constrained by household responsibilities. These findings call into question neoliberal notions that market forces can solve societal problems such as gender inequality.
The Crisis of US Hegemony in the Era of Obama: Four Views from Latin America
Authors: Buono R.A. Dello
Published: September 2011

The unraveling of the Washington Consensus in Latin America is part of a broader decline of US hegemony in the region and beyond. Four distinct approaches by Latin American analysts from Argentina, Chile, Mexico, and Cuba are introduced that examine different aspects of this decline. It is argued that any serious analysis of regional hegemony must include consideration of the interrelationship between economic and military factors; the emergent modalities of exercising hegemony such as free trade agreements; the power structure of the hegemonic state; and the broader context of the global political economy.
The United States and Latin America: Beyond Free Trade
Authors: Figueredo Darío Salinas
Published: September 2011

Trade policies have long been configured into the history of Latin America. In virtually all such policies, US interests can be readily discerned. Recent experiences in a neoliberal context have witnessed a rearrangement of interests, forces, and scenarios at the global level. The weakening of the role of the state in allocating resources and in defining national agendas has been notable. Wherever proposals for democratization have appeared and have sought to distance themselves from hegemonic policies, the issues of free trade and commerce begin to reveal important aspects of interrelationship between development, regional integration, cooperation, and security.
Taxonomy for child well-being indicators: A framework for the analysis of the well-being of children
Authors: Ben-Arieh Asher , Frønes Ivar
Published: September 2011

Recent years have brought a dramatic rise in the number of efforts to measure and monitor the status of children. Yet, despite numerous efforts and reports with ‘Child indicators’ in the title, the field of social child indication is fragmented and lacking a unifying taxonomy. The more ambitious the analysis and the more elaborate the statistics, the stronger the need for a common language used by all. This article tries to suggest such a taxonomy.
‘You could just ignore me’: Situating peer exclusion within the contingencies of girls’ everyday interactional practices
Authors: Svahn Johanna , Evaldsson Ann-Carita
Published: September 2011

The present article approaches the phenomenon of indirect bullying through detailed analysis of the interactional practices that a group of preadolescent girls make use of as they reconstruct the social organization of their peer group, the effect being that one girl is eventually excluded. The data are drawn from ethnography combined with video recordings of the girls’ peer group interactions in a Swedish elementary school, during one school year. The interactional data cover three different periods of the exclusion process. Overall, the study highlights how processes of social exclusion are situated within the flow of subtle and seemingly innocent actions that are embedded in ordinary everyday interactional peer group practices.
Shape design of the deep-drawing preform for manufacturing of automobile drum clutch hubs
Authors: Park J H , Kim S G , Park Y C , Song X G
Published: September 2011

A large variety of metal forming processes is required in manufacturing for automotive applications. Traditionally, the design process for metal forming tools is based on trial-and-error and on the skill of experienced die-makers. This approach results in high development cost and long lead-times. Especially, the drum clutch requires tight dimensional accuracy in inside diameter and gear shape because it is used as the main component for the automatic transmission. The drum clutch investigated in this study is formed in five forming steps, which are first deep drawing, second deep drawing, restriking, embossing, and Grob processes. Dimensional accuracy of the final products greatly depends upon how much more accurate pre-form is manufactured in the previous forming processes before the Grob process. The deep drawing, restriking, and embossing processes in which the pre-form is formed are very important and decisive steps. Thus in some cases, excessive strain by these operations causes dimensional inaccuracy and cracks initiated from the base and wall of the product.

Based on the above background, the objective of this study is to optimize the pre-form shape and tooling so that excessive thinning and crack formation are avoided while a sharp corner radius and flatness are obtained. Process variables such as the punch shapes both of first and second deep drawing, and punch angle were selected to evaluate the deformation characteristics. The optimum parameters were determined from forming simulations using commercial finite element method codes, DEFORM-2D, specifically developed for metal forming simulation. Finally, experiments for the whole drum clutch forming processes were carried out to verify the optimized forming parameters and the analytical results.
Predicting the survival rate of mouse embryonic stem cells cryopreserved in alginate beads
Authors: Sambu S , Xu X , Ye H , Cui Z F
Published: September 2011

Stem cell cryopreservation in three-dimensional (3D) scaffolds may offer better protection to cells leading to higher survival rates. However, it introduces heterogeneity in cryoprotective agent (CPA) concentrations, durations of exposure to CPA, and freezing and thawing rate within constructs. This paper applies a mathematical model which couples the mass transport of dimethyl sulphoxide (DMSO) in a cell-seeded spherical construct and cell membrane transport into mouse embryonic stem cells (mESCs) to predict overall cell survival rate (CSR) based on CPA equilibrium exposure times ( tE) and concentrations. The effect of freeze-concentration is also considered. To enable such a prediction, a contour plot was constructed using experimental data obtained in cryopreservation of cell suspensions with DMSO at a cooling rate of 1 °C/min. Thereafter, the diffusion in the alginate bead and the membrane transport of CPA was numerically simulated. Results were mapped onto the survival rate contours yielding ‘predicted’ CSR. The effects of loading time, hindrance, construct radius, and CPA concentration on predicted CSR were examined. From these results, an operation window with upper and lower tE of 12–19 min (for 0.6 mm radius beads and 1.4 M DMSO) yielded an overall viability of 60 per cent. The model predictions and the best experimental cryopreservation results with encapsulated mESCs were in agreement. Hence, optimization based on post-thaw CSR can accelerate the identification of cryopreservation protocols and parameters for maximizing cell survival.
The tribological behaviour of different clearance MOM hip joints with lubricants of physiological viscosities
Authors: Hu X Q , Wood R J K , Taylor A , Tuke M A
Published: September 2011

Clearance is one of the most influential parameters on the tribological performance of metal-on-metal (MOM) hip joints and its selection is a subject of considerable debate. The objective of this paper is to study the lubrication behaviour of different clearances for MOM hip joints within the range of human physiological and pathological fluid viscosities. The frictional torques developed by MOM hip joints with a 50 mm diameter were measured for both virgin surfaces and during a wear simulator test. Joints were manufactured with three different diametral clearances: 20, 100, and 200 µm. The fluid used for the friction measurements which contained different ratios of 25 per cent newborn calf serum and carboxymethyl cellulose (CMC) with the obtained viscosities values ranging from 0.001 to 0.71 Pa s. The obtained results indicate that the frictional torque for the 20 µm clearance joint remains high over the whole range of the viscosity values. The frictional torque of the 100 µm clearance joint was low for the very low viscosity (0.001 Pa s) lubricant, but increased with increasing viscosity value. The frictional torque of the 200 µm clearance joint was high at very low viscosity levels, however, it reduced with increasing viscosity. It is concluded that a smaller clearance level can enhance the formation of an elastohydrodynamic lubrication (EHL) film, but this is at the cost of preventing fluid recovery between the bearing surfaces during the unloaded phase of walking. Larger clearance bearings allow a better recovery of lubricant during the unloaded phase, which is necessary for higher viscosity lubricants. The selection of the clearance value should therefore consider both the formation of the EHL film and the fluid recovery as a function of the physiological viscosity in order to get an optimal tribological performance for MOM hip joints. The application of either 25 per cent bovine serum or water in existing in vitro tribological study should also be revised to consider the relevance of clinic synovial fluid viscosities and to avoid possible misleading results.
Computational model of an infant brain subjected to periodic motion simplified modelling and bayesian sensitivity analysis
Authors: Batterbee D C , Sims N D , Becker W , Worden K , Rowson J
Published: September 2011

Non-accidental head injury in infants, or shaken baby syndrome, is a highly controversial and disputed topic. Biomechanical studies often suggest that shaking alone cannot cause the classical symptoms, yet many medical experts believe the contrary. Researchers have turned to finite element modelling for a more detailed understanding of the interactions between the brain, skull, cerebrospinal fluid (CSF), and surrounding tissues. However, the uncertainties in such models are significant; these can arise from theoretical approximations, lack of information, and inherent variability. Consequently, this study presents an uncertainty analysis of a finite element model of a human head subject to shaking. Although the model geometry was greatly simplified, fluid-structure-interaction techniques were used to model the brain, skull, and CSF using a Eulerian mesh formulation with penalty-based coupling. Uncertainty and sensitivity measurements were obtained using Bayesian sensitivity analysis, which is a technique that is relatively new to the engineering community. Uncertainty in nine different model parameters was investigated for two different shaking excitations: sinusoidal translation only, and sinusoidal translation plus rotation about the base of the head. The level and type of sensitivity in the results was found to be highly dependent on the excitation type.
The biomechanical effect of changes in cancellous bone density on synthetic femur behaviour
Authors: Nicayenzi B , Shah S , Schemitsch E H , Bougherara H , Zdero R
Published: September 2011

Biomechanical researchers increasingly use commercially available and experimentally validated synthetic femurs to mimic human femurs. However, the choice of cancellous bone density for these artificial femurs appears to be done arbitrarily. The aim of the work reported in this paper was to examine the effect of synthetic cancellous bone density on the mechanical behaviour of synthetic femurs. Thirty left, large, fourth-generation composite femurs were mounted onto an Instron material testing system. The femurs were divided evenly into five groups each containing six femurs, each group representing a different synthetic cancellous bone density: 0.08, 0.16, 0.24, 0.32, and 0.48 g/cm3. Femurs were tested non-destructively to obtain axial, lateral, and torsional stiffness, followed by destructive tests to measure axial failure load, displacement, and energy. Experimental results yielded the following ranges and the coefficient of determination for a linear regression ( R2) with cancellous bone density: axial stiffness (range 2116.5–2530.6 N/mm; R2 = 0.94), lateral stiffness (range 204.3–227.8 N/mm; R2 = 0.08), torsional stiffness (range 259.9–281.5 N/mm; R2 = 0.91), failure load (range 5527.6–11 109.3 N; R2 = 0.92), failure displacement (range 2.97–6.49 mm; R2 = 0.85), and failure energy (range 8.79–42.81 J; R2 = 0.91). These synthetic femurs showed no density effect on lateral stiffness and only a moderate influence on axial and torsional stiffness; however, there was a strong density effect on axial failure load, displacement, and energy. Because these synthetic femurs have previously been experimentally validated against human femurs, these trends may be generalized to the clinical situation. This is the first study in the literature to perform such an assessment.
Numerical investigation of vortex generators to reduce cross-passage flow phenomena in compressor stator end-walls
Authors: Ortmanns J , Pixberg C , Gümmer V
Published: September 2011

The numerical results presented in this article demonstrate the ability of single-vortex generators to reduce the cross-passage secondary flow in a high-turning stator vane passage. The sensitivities of the induced vortex flow are determined in an initial study by varying the geometrical parameters. The visualization of the flow patterns and the determination of the stator vane performance show that the efficiency and the working range can be increased by applying single-vortex generators. The vortex generator design has to achieve a balance between the magnitude of vorticity induced to reduce the secondary flow phenomena and the additional losses associated with the produced vortex flow.