bluuebunny/crossref_metadata_2025 huggingface dataset:
Virtual Brokerage and Closure
Authors: Shen Cuihua , Monge Peter , Williams Dmitri
Published: August 2012

This study proposes a structural approach to examining online bridging and bonding social capital in a large virtual world. It tests the effects of individual players’ network brokerage and closure on their task performance and trust of other players. Bridging social capital is operationalized as brokerage, the extent to which one is tied to disconnected others, and bonding social capital as closure, the extent to which one is embedded in a densely connected group. Social networks were constructed from behavioral server logs of EverQuest II, a Massively Multiplayer Online Game. Results provided strong support for the structural model, demonstrating that players’ network brokerage positively predicted their task performance in the game and players embedded in closed networks were more likely to trust each other.
The Intersection of Gender and Ethnic Identities in the Cuzco–Machu Picchu Tourism Industry
Authors: Ypeij Annelou
Published: August 2012

A large number of local people work in the lowest echelons of the tourist market in the Cuzco–Machu Picchu region. An examination of three groups—indigenous women who pose for tourists’ cameras in the village of Pisac, male tour guides who work on the Inca Trail, and women weavers in the village of Chinchero—reveals the ways in which ethnicity, gender, and tourism work are interrelated. In particular, it shows that ethnic identity should not be limited to indigenousness and women. Both indigenous people and mestizos, women and men use their ethnic identities in their tourism work. Further, it calls into question the division between staged and real identities that is often made in tourism studies, suggesting that tourism work has become an integral part of these people’s lives, social relations, and identities whether tourists are present or not.

Un gran número de gente local trabaja en los eslabones inferiores del marcado turístico en la región Cuzco–Machu Picchu. Un examen de tres grupos—mujeres indígenas quienes posan para las cámaras de los turistas en la aldea de Pisac, hombres quienes fungen como guías turísticos en el camino Inca, y mujeres tejedoras en la aldea de Chincheros—revelan las formas por las cuales la etnia, género, y el empleo turístico están interrelacionados. En particular se demuestra que la identidad étnica no se puede limitar al indigenismo y las mujeres. Tanto los indígenas como mestizos, tanto mujeres como hombres usan su identidad indígena en su trabajo turístico. Además se cuestiona la división entre identidad efectuada y real que tanto se hace en los estudios del turismo, sugiriendo que el empleo turístico se ha convertido en parte integral de la vida de estas gentes, relaciones sociales e identidades estén o no presentes los turistas.
Synchronization of complex dynamical networks under time delays with occurrence probabilities
Authors: Yan Youyun
Published: August 2012

This paper studies synchronization of complex dynamical networks where time-varying coupling delays and the node with time-varying delay are considered. The occurrence probability of each coupling time delay is considered. Synchronization conditions are derived in terms of linear matrix inequalities. An example is provided to illustrate the effectiveness and applicability of the proposed method.
Synchrony in the onset of mental state understanding across cultures? A study among children in Samoa
Authors: Mayer Andreas , Träuble Birgit E.
Published: August 2012

The development of false belief understanding in Samoa was investigated in two studies testing more than 300 children. Children’s understanding was assessed with a change of location task. The results of study 1 suggest that Samoan children improve gradually and slowly, with no succeeding majority before 8 years of age. One third of the 10–13-year-olds still failed. Study 2 used a different translation among 55 children from 4–8 years of age and supports the former results. These findings speak for the cultural variability of theory of mind development and provide the first cross-cultural continuous survey on false belief understanding of children older than 5 years of age with a large sample in a place where mental states are no suitable object for conjecture.
Spirituality and Common Dyadic Coping
Authors: Austin Jennifer L. , Falconier Mariana K.
Published: August 2012

This study examined whether spirituality and dyadic coping protected partners from becoming psychologically aggressive toward each other using secondary, cross-sectional data from a sample of 104 Latino couples living in the Washington, D.C. metropolitan area. The model tested was based on Bodenmann’s Systemic Transactional model and incorporated an Actor–Partner Interdependence Model approach. Structural equation modeling results indicated that each partner’s spirituality had a direct negative effect on their own psychological aggression and a direct positive effect on their own supportive dyadic coping and the couple’s common dyadic coping. Each partner’s spirituality also had an indirect effect on both partners’ psychological aggression through increases in the couple’s common dyadic coping. Supportive dyadic coping was not found to mediate the relation between spirituality and psychological aggression. Limitations of the study as well as clinical, programmatic, and research implications are discussed.
Correlates of Emotional Support and Negative Interaction Among African Americans and Caribbean Blacks
Authors: Lincoln Karen D. , Taylor Robert Joseph , Chatters Linda M.
Published: August 2012

This study explores the relationship of family and demographic factors to the frequency of receiving emotional support and the frequency of engaging in negative interactions with family members (i.e., criticism, burden, and being taken advantage of). The study uses the ambivalence framework and data from the National Survey of American Life, a national sample of African Americans and Caribbean Blacks (Caribbean Blacks). Overall, no significant differences were found between African Americans and Caribbean Blacks in the frequency of emotional support or negative interaction; several significant correlates (e.g., age, family closeness) were found for both groups. However, a number of unique associations were also demonstrated (e.g., marital status, frequency of family contact), indicating differences in the ways that these variables operate within the two populations. These and other findings are discussed in relation to the ambivalence framework and subgroup differences in family phenomena within the Black population.
Acute Otitis Media in Infants
Authors: Sibbald Andrés D.
Published: August 2012

Acute otitis media has changed conceptually from being a feared infection with severe complications to a modest disease that should be treated for symptomatic relief but often without immediate antimicrobials. This holds true for infants and children with nonsevere forms of the illness if the parents and the clinician agree to a strategy of watchful waiting with easy access for follow‐up. Accurate otologic examination is critical for disease recognition, but the initial choice of treatment must also consider the general impact that the disease produces in each individual patient. The appraisal of the symptoms that characterize the illness in a child, matched with the otoscopic intensity of the disease, provide a comprehensive estimation of overall severity that many experts have used for research. The perspectives examined in this article and the schematic construct that proposes considering disease and illness independently may help to bring the current paradigm of acute otitis media into everyday pediatric practice as a model for a more rational and personalized management of each patient.
Readability Assessment of Patient Education Materials on Major Otolaryngology Association Websites
Authors: Eloy Jean Anderson , Li Shawn , Kasabwala Khushabu , Agarwal Nitin , Hansberry David R. , Baredes Soly , Setzen Michael
Published: August 2012

Objective

Various otolaryngology associations provide Internet‐based patient education material (IPEM) to the general public. However, this information may be written above the fourth‐ to sixth‐grade reading level recommended by the American Medical Association (AMA) and National Institutes of Health (NIH). The purpose of this study was to assess the readability of otolaryngology‐related IPEMs on various otolaryngology association websites and to determine whether they are above the recommended reading level for patient education materials.

Study Design and Setting

Analysis of patient education materials from 9 major otolaryngology association websites.

Methods

The readability of 262 otolaryngology‐related IPEMs was assessed with 8 numerical and 2 graphical readability tools. Averages were evaluated against national recommendations and between each source using analysis of variance (ANOVA) with post hoc Tukey’s honestly significant difference (HSD) analysis. Mean readability scores for each otolaryngology association website were compared.

Results

Mean website readability scores using Flesch Reading Ease test, Flesch‐Kincaid Grade Level, Coleman‐Liau Index, SMOG grading, Gunning Fog Index, New Dale‐Chall Readability Formula, FORCAST Formula, New Fog Count Test, Raygor Readability Estimate, and the Fry Readability Graph ranged from 20.0 to 57.8, 9.7 to 17.1, 10.7 to 15.9, 11.6 to 18.2, 10.9 to 15.0, 8.6 to 16.0, 10.4 to 12.1, 8.5 to 11.8, 10.5 to 17.0, and 10.0 to 17.0, respectively. ANOVA results indicate a significant difference (P <. 05) between the websites for each individual assessment.

Conclusion

The IPEMs found on all otolaryngology association websites exceed the recommended fourth‐ to sixth‐grade reading level.
Retrospective analysis of outcome data with regards to the use of Phisio®-, Bioline®- or Softline®-coated cardiopulmonary bypass circuits in cardiac surgery
Authors: Reser D , Seifert B , Klein M , Dreizler T , Hasenclever P , Falk V , Starck C
Published: August 2012

Background: Numerous cardiopulmonary bypass circuits with various coatings designed to reduce the inflammatory response and to provide better hemocompatibility are available. The aim of this study was to compare the effect of phosphorylcholine-coated, albumin-heparin-coated and synthetic polymer-coated perfusion tubing systems on patient outcome. Methods: We performed a retrospective database review of elective patients between January 1st 2010 and December 31st 2010. Demographics, preoperative, operative, postoperative data and follow-up were collected and statistically analysed. Results: We identified 201 patients and formed three groups: Group 1 with phosphorylcholine coating (n=133), Group 2 with albumin-heparin coating (n=32) and Group 3 synthetic polymer coating (n=36). Mean age was 68±11years, additive Euroscore 5.8±2.7. In-hospital outcomes were comparable between the groups without statistically significant differences. The overall 30-day and 1-year late survival were 98.5% and 96.7±1.9%, respectively. Conclusions: Our findings suggest that in-hospital and follow-up outcomes are comparable in cardiac surgery patients after using either phosphorylcholine-coated, albumin-heparin-coated or synthetic polymer-coated circuits during cardiopulmonary bypass.
Community food growing and the role of women in the alternative economy in Tower Hamlets
Authors: Metcalf Kate , Minnear Julia , Kleinert Tabitha , Tedder Victoria
Published: August 2012

Women’s Environmental Network organises support and training for community gardens within East London. This practitioners’ perspective will consider some of the ways in which this helps to gain local resilience to economic and cultural pressures as well as creating greater access to green spaces.
A randomized controlled pilot study assessing the feasibility of combined motor–cognitive training and its effect on gait characteristics in the elderly
Authors: de Bruin Eling D , van het Reve Eva , Murer Kurt
Published: August 2012

Objective:

(1) To develop a motor–cognition training programme; (2) to evaluate the ability to recruit and retain elderly people; (3) to assess the effects of the interventions.

Design:

Pilot randomized controlled trial.

Setting:

Assisted living facility.

Participants:

Sixteen subjects (11 female) living in an assisted living facility were randomized to a motor or motor–cognition group.

Interventions:

Both groups received machine-driven strength training and balance exercises for 45 minutes, twice weekly, for 12 weeks. In addition, the motor–cognition group received computerized training for attention 3–5 times per week for 10 weeks.

Main outcome measures:

Baseline and post-intervention (12 weeks) assessments focused on recruitment, attrition and adherence. Secondary outcome measures assessed dual-task costs of gait (velocity, cadence, step time, step length), expanded timed get-up-and-go, falls efficacy and reaction time.

Results:

Of 35 subjects initially approached, 16 started and 14 completed the study, resulting in 46% recruitment, 19% attrition and >80% adherence rates. There is more evidence of altered levels in the motor–cognitive treatment group with significant differences in average change for fear of falling ( P = 0.017) and foot reaction time ( P = 0.046). No statistical significance was reached for gait parameters.

Conclusions:

Motor–cognition training is feasible and shows trends to stronger improvement in walking and reaction time. The application in a main study is deemed feasible. A minimum of ±55 subjects per group are required to achieve a power of 80% at the 5% level of significance based on step length and considering the expectable attrition rate in a required larger scale study.
Chinese adaptation and validation of the patellofemoral pain severity scale
Authors: Cheung Roy TH , Ngai Shirley PC , Lam Priscillia L , Chiu Joseph KW , Fung Eric YH
Published: August 2012

Objective:

This study validated the Patellofemoral Pain Severity Scale translated into Chinese.

Design and setting:

The Chinese Patellofemoral Pain Severity Scale was translated from the original English version following standard forward and backward translation procedures recommended by the International Society for Pharmacoeconomics and Outcomes Research. The survey was then conducted in clinical settings by a questionnaire comprising the Chinese Patellofemoral Pain Severity Scale, Kujala Scale and Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index.

Subjects:

Eighty-four Chinese reading patients with patellofemoral pain were recruited from physical therapy clinics.

Main measures:

Internal consistency of the translated instrument was measured by Cronbach alpha. Convergent validity was examined by Spearman rank correlation coefficient (rho) tests by comparing its score with the validated Chinese version of the Kujala Scale and the WOMAC Osteoarthritis Index while the test–retest reliability was evaluated by administering the questionnaires twice.

Results:

Cronbach alpha values of individual questions and their overall value were above 0.85. Strong association was found between the Chinese Patellofemoral Pain Severity Scale and the Kujala Scale (rho = -0.72, p < 0.001). Moderate correlation was also found between Chinese Patellofemoral Pain Severity Scale with the WOMAC Osteoarthritis Index (rho = 0.63, p < 0.001). Excellent test–retest reliability (Intraclass correlation coefficient = 0.98) was demonstrated.

Conclusions:

The Chinese translated version of the Patellofemoral Pain Severity Scale is a reliable and valid instrument for patients with patellofemoral pain.
Use of Electron Microscopy to Classify Canine Perivascular Wall Tumors
Authors: Palmieri C. , Avallone G. , Cimini M. , Roccabianca P. , Stefanello D. , Salda L. Della
Published: August 2012

The histologic classification of canine perivascular wall tumors (PWTs) is controversial. Many PWTs are still classified as hemangiopericytomas (HEPs), and the distinction from peripheral nerve sheath tumors (PNSTs) is still under debate. A recent histologic classification of canine soft tissue sarcomas included most histologic types of PWT but omitted those that were termed undifferentiated. Twelve cases of undifferentiated canine PWTs were evaluated by transmission electron microscopy. The ultrastructural findings supported a perivascular wall origin for all cases with 4 categories of differentiation: myopericytic (n = 4), myofibroblastic (n = 1), fibroblastic (n = 2), and undifferentiated (n = 5). A PNST was considered unlikely in each case based on immunohistochemical expression of desmin and/or the lack of typical ultrastructural features, such as basal lamina. Electron microscopy was pivotal for the subclassification of canine PWTs, and the results support the hypothesis that canine PWTs represent a continuum paralleling the phenotypic plasticity of vascular mural cells. The hypothesis that a subgroup of PWTs could arise from a pluripotent mesenchymal perivascular wall cell was also considered and may explain the diverse differentiation of canine PWTs.
Measurement and calculation of adiabatic surface temperature in a full-scale compartment fire experiment
Authors: Byström Alexandra , Cheng Xudong , Wickström Ulf , Veljkovic Milan
Published: August 2012

Adiabatic surface temperature is an efficient way of expressing thermal exposure. It can be used for bridging the gap between fire models and temperature models, as well as between fire testing and temperature models. In this study, a full-scale compartment fire experiment with wood crib fuel was carried out in a concrete building. Temperatures were measured with plate thermometers and ordinary thermocouples. Five plate thermometers and five thermocouples with a diameter of 0.25 mm were installed at different positions. These two different temperature devices recorded different temperatures, especially near the floor surface. The adiabatic surface temperature was derived by a heat balance analysis from the plate thermometer measurements. The thermal inertia of the plate thermometer was taken into account to correct the measured results. In addition, the fire experiment scenario was also simulated with fire dynamics simulator. The fire source was specified as a given heat release rate, which was calculated from the measured mass loss rate of the wood fuel. The adiabatic surface temperatures at these measuring positions were simulated by the fire dynamics simulator model and compared with the experimental adiabatic surface temperatures. The comparative results showed that fire dynamics simulator predicted the adiabatic surface temperature accurately during the steady-state period.
Effect of partial substitution of aluminum hydroxide with colemanite in fire retarded low-density polyethylene
Authors: Isitman Nihat A , Kaynak Cevdet
Published: August 2012

Metal hydroxides have long been considered as abundant and low-cost fillers for the development of halogen-free flame-retarded polyolefins. However, large filler loading levels are required in the matrix resin to achieve satisfactory fire retardant performance, which results in deteriorated processing characteristics and poor mechanical properties of compounds. Therefore, this study was aimed at improving the fire retardancy of low-density polyethylene and decreasing the total filler loading in the resin using combinations of aluminum hydroxide and a natural hydrated calcium borate, namely, colemanite mineral. Flame retardancy was studied by the mass loss calorimeter analysis, limiting oxygen index measurements, and UL94 classification. Peak heat release rate and total heat evolved were lowered by around 20% and 15%, respectively, with partial replacement of aluminum hydroxide by colemanite, which facilitated the use of lower total filler loading in the resin. Depending on colemanite content and total filler loading, limiting oxygen index was increased by 1%–4% while maintaining the UL94 V-0 rating. Fire retardant effect of colemanite used in conjunction with aluminum hydroxide was attributed to better protective character of fire residues and more effective fuel trapping in the condensed phase. Lower elastic modulus and higher ductility was obtained due to decreased total filler loading in the matrix.
Protective effect of lycopene on deltamethrin-induced histological and ultrastructural changes in kidney tissue of rats
Authors: El-Gerbed Mohamed SA
Published: August 2012

Deltamethrin is globally used in crop protection and control of malaria and other vector-borne diseases. It has a potent insecticidal activity with an appreciable safety margin. However, a number of studies have demonstrated nephrotoxicity of deltamethrin in mammalian and nonmammalian species. Lycopene, a carotenoid occurring naturally in tomatoes, has attracted considerable attention as an antioxidant. This study was focused on investigating the possible protective effect of coadministration of lycopene on deltamethrin toxicity. In this study, male albino rats were divided into four groups of 10 animals each: group I served as control, which received standard diet; group II received oral administration of deltamethrin (1.28 mg/kg per day) for 30 days; group III received both deltamethrin and lycopene (1 mg/kg per day); group IV received lycopene (1 mg/kg per day). After the experiment, the animals were anesthetized and the cytokine, tumor necrosis factor-α (TNF-α), in the serum was measured; the kidney was taken for histological and ultrastructural studies. Deltamethrin significantly increased the TNF-α. The histopathological examination of kidney showed mild necrotic changes. Ultrastructural changes in renal proximal tubules of deltamethrin-treated group included an increased number and irregular shape of mitochondria with sparse fragmented cristae, serious ultrastructural lesions in renal proximal tubular lining cells, vacuolar degeneration in the epithelial cells, increased number of lysosomes and loss of apical microvilli. In addition, focal segmental thickening and the duplication of glomerular basement membrane and podocyte changes were observed. Histopathological and ultrastructural study showed some protective effect of lycopene on kidney tissues.
Impact of probiotic-supplemented diet on the expression level of lactate dehydrogenase in the leukocytes of rabbits
Authors: Ghoneim Magdy AE , Moselhy Said S
Published: August 2012

Probiotics are known as living, nonpathogenic microorganisms that colonize the intestine and provide benefit to the host. The present study aims to measure one important energy metabolism-related enzyme activity in blood of rabbits fed on probiotics of recommended concentration. In addition, it also aims for the evaluation of the expression level of lactate dehydrogenase (LDH) enzyme using reverse transcriptase-polymerase chain reaction (RT-PCR) technique. Two groups of rabbits are used: control group receiving normal standardized diet and the other probiotic-supplemented group receiving the same diet containing probiotic, namely, Mega acidophilus (200 million cfu/kg body weight/day) for 4 weeks. The obtained results revealed that the rabbits supplemented with probiotics showed a significant decrease in the levels of serum total cholesterol (TC), triacylglycerol, high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c) when compared with control group. Risk factors detected by measuring TC/HDL-c and LDL-c/HDL-c ratios showed statistically significant decrease in probiotic-supplemented rabbits when compared with control group. In addition, blood glucose and total LDH activity were elevated in probiotic-supplemented rabbits when compared with control group. RT-PCR products of LDH-M gene produced two specific amplicons. One amplicon has the expected size of 243 bp from all samples of rabbits as revealed by GelPro software. The level of LDH-M expression was found to be increased in the probiotic-supplemented group. However, unexpected amplicons are produced at 586 bp in all the samples, which may be a dimeric form of the amplified region. It was concluded that this probiotic blend is beneficiary for the metabolic reactions of lipids in the body. Moreover, LDH expression level can be considered as a biomarker for the effect of probiotic and hence monitoring the metabolic changes as reflected from its administration.
Building School and Teacher Capacity to Eliminate the School-to-Prison Pipeline
Authors: Osher David , Coggshall Jane , Colombi Greta , Woodruff Darren , Francois Samantha , Osher Trina
Published: August 2012

The school-to-prison pipeline (STPP)—disproportionately impacting students of color— involves a set of interactions between and among children, youth, their families, school personnel, other service providers, and gatekeepers to such outcomes as incarceration or college. Educators can, through their interactions with and expectations for students, contribute significantly to negative outcomes or lead the charge toward more positive outcomes. In this article, the authors first examine four factors that amplify the pipeline to prison, which if addressed effectively by educators can reduce it while creating alternative pathways to success. They then provide concrete suggestions for bolstering educator and school capacity to eliminate the STPP and implications for teacher preparation.
Interactive Web-Based Breastfeeding Monitoring
Authors: Ahmed Azza H. , Ouzzani Mourad
Published: August 2012

Background:

Strategies that promote higher exclusive breastfeeding rate and duration are highly recommended. To date, no study has tested the feasibility of Web-based monitoring among breastfeeding mothers.

Goals:

To develop an interactive Web-based breastfeeding monitoring system (LACTOR) and examine its feasibility, usability, and acceptability among breastfeeding mothers.

Methods:

A prospective, descriptive, mixed-methods study was conducted. Mothers who met the study inclusion criteria were recruited from mother infant units in 2 Midwestern hospitals in the United States. Mothers were asked to enter their breastfeeding data daily through the system for 30 days and then submit an online exit survey. This survey consisted of a system usability scale and mothers’ perceptions form. Twenty-six mother/infant dyads completed the study.

Results:

The Feasibility of LACTOR was established by mothers’ compliance in entering their breastfeeding data. The mean was 8.87 (SD = 1.21) daily entries, and the range was 6-13 times per day. Usability scale total mean score was 3.35 (SD = 0.33; scale range 0-4). Ninety-two percent of the mothers thought that they did not need to learn many skills before they started to use LACTOR and did not need any technical support. Mothers reported that the monitoring was beneficial and gave them the chance to track their infants’ feeding patterns and detect any problems early.

Conclusions:

This study demonstrated the feasibility of LACTOR, and it was user-friendly and acceptable among mothers. Further studies to test its effect on breastfeeding outcomes are needed.
Occupational Gender Segregation, Globalization, and Gender Earnings Inequality in U.S. Metropolitan Areas
Authors: Gauchat Gordon , Kelly Maura , Wallace Michael
Published: August 2012

Previous research on gender-based economic inequality has emphasized occupational segregation as the leading explanatory factor for the gender wage gap. Yet the globalization of the U.S. economy has affected gender inequality in fundamental ways and potentially diminished the influence of occupational gender segregation. We examine whether occupational gender segregation continues to be the main determinant of gender earnings inequality and to what extent globalization processes have emerged as important determinants of inequality between women’s and men’s earnings. We study factors contributing to the gender earnings ratio as well as the median earnings of men and women for 271 U.S. metropolitan areas. The results indicate that occupational segregation is still the leading determinant of gender earnings inequality, that its effects are only slightly diminished by the presence of globalization, and that various aspects of the global economy independently influence the gender earnings gap.
Capital Accumulation and the Historical Decline of Liberal Individualism
Authors: O’Flynn Micheal
Published: August 2012

‘The individual’ has been a central feature of western political thought for 300 years. However, the continuous transformation of the capitalist system, its tendency toward monopoly, its accelerating extension of commodification into the remaining global commons, particularly into the realms of knowledge and culture, is undermining the political function of this fundamental concept. The subordination and/or elimination of the owner-entrepreneur means that claims to represent ‘the individual’ appear less and less credible. Increasingly coercive measures are required to facilitate the extraction of surplus value. The decline of liberal individualism (in its 19th-century form at least) is not temporary. Its central tenets will never again be fully embraced since they no longer offer a credible means of representing the needs of either industrial or finance capitalism in a favourable light.
Effect of temperature on the strength of a centrifugal compressor impeller for a turbocharger
Authors: Zheng Xinqian , Jin Lei , Du Tao , Gan Binlin , Liu Fenghu , Qian Huihua
Published: August 2012

High pressure ratio turbocharger technology is used to decrease fuel consumption, reduce emissions and improve power density of an internal combustion engine. The centrifugal compressor is the turbocharger’s core component. The reliability of its impeller becomes critical as the pressure ratio gets higher and the temperature starts playing an important role. In order to study the effect of the flow temperature on the reliability of a centrifugal compressor impeller, solid–fluid coupling is used to calculate the temperature distribution on the impeller surface. This temperature distribution is then applied as boundary condition in three-dimensional finite element analysis to analyze impeller stress. The results show that the percentage of impeller stress caused by thermal load remains approximately constant (about 2%) at different pressure ratios, which does not increase with increasing pressure ratio. Centrifugal load plays an absolutely critical role in the impeller stress at different pressure ratios. High pressure ratio also leads to an increase of air temperature, which causes higher material temperature and consequently the lower ultimate tensile strength of the impeller material. The maximum compressor pressure ratio which the impeller can bear decreases from 4.6 to 4.2 for the researched compressor if the effect of temperature on the ultimate tensile strength was considered. That means the effect of the temperature on compressor impeller strength and reliability at high pressure ratio should be considered while it can be ignored at low pressure ratio.
Coupled transverse vibration modeling of drillstrings subjected to torque and spatially varying axial load
Authors: Ghasemloonia Ahmad , Rideout D Geoff , Butt Stephen D
Published: August 2012

Predicting and mitigating unwanted vibration of drillstrings is an important subject for oil drilling companies. Uncontrolled vibrations cause premature failure of the drillstring and associated components. The drillstring is a long slender structure that vibrates in three primary coupled modes: torsional, axial and transverse. Among these coupled modes, the transverse mode is the major cause of drillstring failures and wellbore washout. Modal analysis of drillstrings reveals critical frequencies and helps drillers to avoid running the bit near critical modes. In this article, the coupled orthogonal modes of transverse vibration of a drillstring in the presence of torque and spatially varying axial force (due to mud hydrostatic effect, self-weight and hook load) are derived and the mode shapes and natural frequencies are determined through the expanded Galerkin method. The results are verified by the nonlinear finite element method. Modal mass participation factor, which represents how strongly a specific mode contributes to the motion in a certain direction, is used to determine the appropriate number of modes to retain so that computational efficiency can be maximized.
Analysis of annulus-shaped compliant pivot with series–parallel leaves
Authors: Bi Shusheng , Qiao Tao , Zhao Hongzhe , Yao Yanbin
Published: August 2012

Annulus-shaped compliant pivot, formed by well-proportioned compliant modules between the outer ring and inner ring, can be employed in precision mechanical systems due to good performances. Especially for the multi-series leaves in one module, the annulus-shaped compliant pivot can fulfill a large displacement range without any axial drift in theory. In the design of the annulus-shaped compliant pivot, the load–displacement behavior and the stress analysis with analytical forms are important consideration. However, in the literature, there is few detailed work. In this article, a general annulus-shaped compliant pivot model formed by series–parallel leaves is first analytically established for the load–displacement behavior and the stress prediction. These calculations are based on accurate approximation of a beam flexure. Firstly, a loaded moment is decomposed into universal loads by combining the geometric compatibility condition. The stiffness accurate approximation is then analytically obtained, which provides a simple design strategy. Furthermore, the stresses in every leaf are obtained so that the annulus-shaped compliant pivot with large motion range can be actualized by stress checking. Lastly, the analytical model has been verified by commercial finite element analysis software ANSYS.
Mathematical modeling of a generic multi-profile form milling cutter
Authors: Khan Mohammed Rajik , Tandon Puneet
Published: August 2012

In order to machine multiple sculptured surfaces with reduced machining time and high accuracy of the machined parts, shape design of a customised multi-point rotary cutting tool needs to be evolved. In the present work, a novel design of a generic multi-profile form milling cutter is developed for machining various multiple sculptured surfaces. This article describes in detail the mathematical model to design an accurate three-dimensional geometry of a generic multi-profile form milling cutter. Use of non-uniform rational B-spline curve(s) and sweep surfaces enables to control the shape of cutting flutes of the generic multi-profile form milling cutter. The article also discusses the methodology to develop a variety of cutters lying in the same conceptual family of multi-profile form milling cutter. To physically visualise the cutter and to show one of the downstream applications once a three-dimensional model of the cutter is available, one of the multi-profile form milling cutters is fabricated. The proposed methodology offers an intuitive high-quality mathematical model for a generic family of multi-profile form milling cutters, which is different from the traditional three-dimensional models.
Volumetric error modeling and compensation considering thermal effect on five-axis machine tools
Authors: Zhang Yi , Yang Jianguo , Xiang Sitong , Xiao Huixiao
Published: August 2012

This article intends to provide an error compensation system for five-axis machine tools. A volumetric error model is established with homogeneous transformation matrix method, from which compensation values of both orientation and position errors can be obtained. Thirty-seven errors on a five-axis machine tool are classified into three categories – functional, random, and negligible errors, among which the effect of the first one on volumetric accuracy is considered as great enough to be included in this model. Some typical modeling methods are discussed on positioning and straightness errors, considering both geometric and thermal effects. Then, we propose a compensation implementation technique based on the function of external machine zero point shift and Ethernet data communication protocol for machine tools. Finally, laser diagonal measurements have been conducted to validate the effectiveness of the proposed volumetric error compensation system.
Heat conduction in one-dimensional functionally graded media based on the dual-phase-lag theory
Authors: Akbarzadeh AH , Chen ZT
Published: August 2012

In this article, heat conduction in one-dimensional functionally graded media is investigated based on the dual-phase-lag theory to consider the microstructural interactions in the fast transient process of heat conduction. All material properties of the media are assumed to vary continuously according to a power-law formulation with arbitrary non-homogeneity indices except the phase lags which are taken constant for simplicity. The one-dimensional heat conduction equations based on the dual-phase-lag theory are derived in a unified form which can be used for Cartesian, cylindrical, and spherical coordinates. A semi-analytical solution for temperature and heat flux is presented using the Laplace transform to eliminate the time dependency of the problem. The results in the time domain are then given by employing a numerical Laplace inversion technique. The semi-analytical solution procedure leads to exact expressions for the thermal wave speed in one-dimensional functionally graded media with different geometries based on the dual-phase-lag and hyperbolic heat conduction theories. The transient temperature distributions have been found for various types of dynamic thermal loading. The numerical results are shown to reveal the effects of phase lags, non-homogeneity indices, and thermal boundary conditions on the thermal responses for different temporal disturbances. The results are verified with those reported in the literature for hyperbolic heat conduction in cylindrical and spherical coordinates.
Comparative investigation of tip leakage flow and its effect on stage performance in shrouded and unshrouded turbines
Authors: Gao Jie , Zheng Qun , Zhang Hai , Chen Hang
Published: August 2012

In order to provide reference for the choice of the turbine architecture in specific application, comparative investigation was conducted to investigate the shrouded and unshrouded rotor tip leakage flows by means of the commercial CFX software, which modeled the flow in a 1.5-stage turbine. Tip leakage loss production mechanisms as well as the effects of tip clearance and pitch–chord ratio on tip leakage and stage performances were discussed and compared in this article. Numerical results show that, the leakage flow at the shroud cavity inlet effectively removes the boundary layer at rotor leading edge, and then reduces the casing secondary flows inside rotor passage. There is a break-even tip clearance at which both the shrouded and unshrouded turbines have the same efficiency, and if tip clearance is less than it, the unshrouded turbine performs better than the shrouded turbine. Compared to the unshrouded turbine, the shrouded turbine can reduce the sensitivity of turbine performances to changes in tip clearance. Moreover, at the given relative change in leakage flow, the relative change in work is approximately twice the relative change in efficiency. Besides, pitch–chord ratio has the different impact on the tip leakage mixing processes in shrouded and unshrouded turbines. It is effective to achieve lower tip leakage losses by turning the leakage flows to reduce mixing losses in shrouded turbines, and by blade tip design or tip clearance treatment to reduce the tip leakage flow in unshrouded turbines.
Pulmonary Function as a Cause of Cognitive Aging
Authors: Emery Charles F. , Finkel Deborah , Pedersen Nancy L.
Published: August 2012

Human aging is associated with decline in cognitive and physical functioning. Although pulmonary function predicts long-term performance (up to 10 years) on measures of cognitive function, recent data suggest the opposite relationship: Cognitive decline predicts self-reported physical limitations. In the study reported here, we utilized dual-change-score models to determine the directional relationship between pulmonary and cognitive function. Our sample consisted of 832 participants (ages 50–85 years at baseline), who were assessed in up to seven waves of testing across 19 years as part of the longitudinal Swedish Adoption/Twin Study of Aging. Changes in pulmonary function led to subsequent changes in fluid cognitive function, specifically, in tasks reflecting psychomotor speed and spatial abilities. There was no evidence that declines in cognitive function led to subsequent declines in pulmonary function. Thus, these data indicate a directional relationship from decreased pulmonary function to decreased cognitive function, a finding that underscores the importance of maintaining pulmonary function to ensure cognitive performance.
Stabilization of fractional-order unstable delay systems by fractional-order controllers
Authors: Kheirizad Iraj , Jalali Ali Akbar , Khandani Khosro
Published: August 2012

In the present paper stabilization of a class of fractional-order unstable delay systems by fractional-order controllers is investigated. To derive the sufficient conditions for stability, an analysis based on the Nyquist stability criterion has been adopted. The analysis is carried out with fractional-order [proportional–integral] and [proportional–derivative] controllers to obtain the upper bound for the time delay. Furthermore, the paper proposes the conditions on the parameters of the controllers which must be fulfilled in order to have a stabilized process. Two illustrated examples using fractional-order controllers are presented for demonstrating the proposed approach.
Distinct phenotypes in mixed connective tissue disease: subgroups and survival
Authors: Szodoray P , Hajas A , Kardos L , Dezso B , Soos G , Zold E , Vegh J , Csipo I , Nakken B , Zeher M , Szegedi G , Bodolay E
Published: August 2012

The aim of the present study was to assess the autoantibody profile, dominant clinical symptoms and cluster characteristics of different Mixed connective tissue disease (MCTD phenotypes. Two-hundred-and-one patients with MCTD were followed-up longitudinally. Five clinical parameters, Raynaud’s phenomenon, pulmonary artery hypertension (PAH), myositis, interstitial lung disease (ILD), erosive arthritis and five auto-antibodies besides anti-U1RNP, antiendothelial cell antibodies (AECA), anti-CCP, anti-cardiolipin (anti-CL), anti-SSA/SSB and IgM rheumatoid factor (RF) were selected for cluster analysis. The mean age of patients was 52.9 ± 12.4 years and the mean follow-up of the disease was 12.5 ± 7.2 years. Patients were classified into three cluster groups. Cluster 1 with 77 patients, cluster 2 with 79 patients and cluster 3 with 45 patients. In cluster 1 the prevalence of PAH (55.8%; p < 0.001), Raynaud’s phenomenon (92.2%; p < 0.001) and livedo reticularis (24.6%, p < 0.001) was significantly greater than in cluster 2 and 3. In cluster 2, the incidence of ILD (98.7%; p < 0.001), myositis (77.2%; p < 0.001), and esophageal dysmotility (89.8%; p < 0.001) was significantly greater than that in cluster 1 and 3. In cluster 3, anti-CCP antibodies were present in 31 of 45 patients (68.8%) with erosions. Anti-CCP antibodies were present in 37 of 42 patients (88.0%) with erosions. PAH, angina, venous thrombosis was observed in cluster 1 and pulmonary fibrosis in cluster 2, musculosceletal damage, gastrointestinal symptoms and osteoporotic fractures were most frequent in cluster 3. Cumulative survival assessment indicated cluster 1 patients having the worst prognosis. Cluster analysis is valuable to differentiate among various subsets of MCTD and useful prognostic factor regarding the disease course.
Reconstruction of the boundary between climate science and politics: The IPCC in the Japanese mass media, 1988–2007
Authors: Asayama Shinichiro , Ishii Atsushi
Published: August 2012

The Intergovernmental Panel on Climate Change (IPCC) plays a significant role in bridging the boundary between climate science and politics. Media coverage is crucial for understanding how climate science is communicated and embedded in society. This study analyzes the discursive construction of the IPCC in three Japanese newspapers from 1988 to 2007 in terms of the science–politics boundary. The results show media discourses engaged in boundary-work which rhetorically separated science and politics, and constructed the iconic image of the IPCC as a pure scientific authority. In the linkages between the global and national arenas of climate change, the media “domesticate” the issue, translating the global nature of climate change into a discourse that suits the national context. We argue that the Japanese media’s boundary-work is part of the media domestication that reconstructed the boundary between climate science and politics reflecting the Japanese context.
The Association of Physical Fitness With Body Mass Index and Waist Circumference in Filipino Preadolescents
Authors: Gonzalez-Suarez Consuelo B. , Caralipio Nenita , Gambito Ephraim , Reyes Josephine Joy , Espino Reil Vinard , Macatangay Ramon
Published: August 2012

Aim. The objective of this study is are to examine the association of preadolescent obesity using body mass index (BMI) and waist circumference (WC) with health-related physical fitness components. Methods. Grades 4 to 6 students in 2 private schools in Manila were included in this study. Height, weight, WC, and BMI were obtained. Physical fitness field tests were sit-and-reach test, 1-minute sit-ups, standing broad jump, 40-m sprint, and 20-m shuttle run. Results. Obese subjects had poorer scores in the field tests except in the sit-and-reach test. BMI and WC were significantly negatively associated with all the physical fitness parameters, except for the 40-m sprint where positive correlation was observed, and in the sit-and-reach test where no correlation was seen. Conclusion. In the management of preadolescent overweight and obesity, exercise programs should therefore be designed toward enhancing these fitness parameters, while not sacrificing enjoyment and creativity.
Adverse Health Effects of Asian Dust Particles and Heavy Metals in Japan
Authors: Onishi Kazunari , Otani Shinji , Yoshida Atsushi , Mu Haosheng , Kurozawa Youichi
Published: August 2012

Asian dust events are now considered an environmental problem rather than a natural seasonal phenomenon. In this study, we evaluated the associations between daily adverse health effects and Asian dust events in Yonago, Japan. Participants included 54 healthy volunteers, who were distributed survey sheets on nasal, ocular, respiratory, and skin effects in February 2009. Moreover, we collected meteorological and air pollutant (nitric oxide, sulfur dioxide, suspended particulate matter) data and determined pollen and metallic element concentrations in total suspended particulates. Both soil-derived metals (Fe, Ca, Al) and contaminating metals (Pb, Cr, Mn, Ni, Zn) were significantly increased on Asian dust days. Multiple regression analyses showed that the score of the skin effect was significantly associated with the levels of suspended particulate matter and Ni. The results show that increased air pollutants on Asian dust days may have skin effects.
Achutha Menon Centre Diabetes Risk Score
Authors: Sathish Thirunavukkarasu , Kannan Srinivasan , Sarma P. Sankara , Thankappan Kavumpurathu Raman
Published: August 2012

The authors aimed to develop a diabetes risk score for primary care providers in rural India. They used the baseline data of 451 participants (15-64 years) of a cohort study in a rural area of Kerala, India. The new risk score with age, family history of diabetes, and waist circumference identified 40.8% for confirmatory testing, had a sensitivity of 81.0%, specificity of 68.4%, positive predictive value of 37.0%, and negative predictive value of 94.0% for an optimal cutoff ≥4 with an area under the receiver operating characteristic curve of 0.812 (95% confidence interval = 0.765-0.860). The new risk score with 3 simple, easy-to-measure, less time-consuming, and less expensive variables could be suitable for use in primary care settings of rural India.