bluuebunny/crossref_metadata_2025 huggingface dataset:
No Evidence for Diagnostic Value of Mallampati Score in Patients Suspected of Having Obstructive Sleep Apnea Syndrome
Authors: Bins Sander , Koster Theodoor D. , de Heij Albert H. , de Vries Akkeline C. , van Pelt Anouk B. , Aarts Mark C. J. , Rovers Maroeska M. , van der Heijden Geert J. M. G.
Published: May 2011

Objective

To analyze whether the Mallampati score is reliable as a simple diagnostic test for predicting obstructive sleep apnea syndrome (OSAS).

Data Sources

A literature search was performed using PubMed, Embase, Scopus, Cochrane, and CINAHL databases.

Review Methods

Studies were ranked by their relevance and validity in a critical appraisal table. Positive and negative predictive values were obtained or recalculated from the selected articles.

Results

Eight relevant articles met the inclusion criteria. Three studies reported predictive values for a Mallampati score of 3 to 4. The prevalence (or prior probability) of OSAS in these 3 studies was 58% (95% confidence interval [CI], 50‐67), 76% (95% CI, 72‐79), and 82% (95% CI, 80‐84), respectively. With a Mallampati score of 1 to 2, the risk of OSAS decreases to 45% (95% CI, 33‐58), 74% (95% CI, 70‐78), and 81% (95% CI, 77‐86), respectively. With a Mallampati score of 3 to 4, the risk of OSAS is 69% (95% CI, 59‐80), 82% (95% CI, 74‐89), and 82% (95% CI, 79‐85), respectively. The differences between the prior and the posterior probabilities are rather small and do not reach statistical significance.

Conclusion

There is no evidence to maintain that the Mallampati score is of added value for ruling in or ruling out a diagnosis of OSAS in patients suspected for OSAS.
Can Intratympanic Dexamethasone Protect against Cisplatin Ototoxicity in Mice with Age‐Related Hearing Loss?
Authors: Parham Kourosh
Published: May 2011

Objective

To determine whether intratympanic (IT) dexamethasone ameliorates cisplatin‐induced ototoxicity in a mouse model of presbycusis.

Study Design

Controlled experimental study.

Setting

Translational science experimental laboratory.

Subjects and Methods

Auditory brainstem response (ABR) thresholds of 24‐month‐old CBA/J‐NIA mice treated with cisplatin were compared 7 days after daily IT injections of dexamethasone (24 mg/mL) or saline.

Results

Because of high (100%) mortality at 16 mg/kg, a single cisplatin dose of 14 mg/kg intraperitoneally was used. At this latter dose, pre‐IT and post‐IT treatment ABR thresholds were available in 13 of 16 mice. In IT saline–treated ears, cisplatin produced up to 9.5‐dB ABR threshold elevations. In IT dexamethasone–treated ears, little protection against cisplatin was observed at 8 or 16 kHz where mean ABR thresholds were elevated. At 24 and 32 kHz, mean ABR threshold elevations were minimal at 0.6 to 1.4 dB. This protection was statistically significant (P ≤. 02).

Conclusions

These results demonstrate, for the first time, a protective effect of a treatment against an ototoxic agent in the presence of age‐related hearing loss. In the presence of age‐related hearing loss, the protective effect of IT dexamethasone has a frequency gradient, being greatest in the high‐frequency region of the cochlea. This latter finding contrasts with our previous report in young mice, in which the protective effect of IT dexamethasone was in the low‐frequency region of the cochlea.
Effect of Aspiration of Perilymph during Stapes Surgery on the Endocochlear Potential of Guinea Pig
Authors: Ikeda Ryoukichi , Nakaya Kazuhiro , Oshima Hidetoshi , Oshima Takeshi , Kawase Tetsuaki , Kobayashi Toshimitsu
Published: May 2011

Objective

Suction applied to the vestibule through the oval window during stapes surgery is considered a primary risk for postoperative sensorineural hearing impairment. This study investigated the mechanism of acute phase change in cochlear function caused by aspiration of the opened oval window.

Study Design

Guinea pig model.

Setting

Academic hospital laboratory.

Subjects and Methods

Guinea pigs were divided into 3 groups: stapes footplate removed without suctioning (6 animals), with indirect suctioning (5 animals), and with direct suctioning of the vestibular perilymph (6 animals). Endocochlear potentials (EPs) were measured at the second turn of the cochlea, and temporal bones were examined histologically.

Results

Removal of the stapes footplate without suctioning caused little change in the EP (original value, 80.12 ± 3.52 mV), indirect suctioning caused minor decline of the EP of 9.14 ± 1.84 mV, and partial recovery ensued, whereas direct but gentle suctioning, resulting in dry vestibule, caused reduction in the EP of 16.38 ± 6.63 mV. Recovery was not observed or incomplete. No animals showed profound decrease in the EP.

Conclusion

Gentle suctioning and removal of the vestibular perilymph can cause a mild decrease in the EP even without damaging the inner ear structures. Therefore, suctioning of the perilymph should be avoided during stapes surgery because acute hearing loss can result even without damaging the inner ear structures. However, hearing loss may not be profound, if suctioning is not vigorous enough to cause damage to the inner ear structures.
RNA Interference of Transforming Growth Factor–β2 in Human Respiratory Fibroblasts
Authors: Wirtz Eric D. , Fredericks Gregory , Robitschek Jon , Cable Benjamin B.
Published: May 2011

Objective

Transforming growth factor–β2 (TGF‐β2) is a principal cytokine of interest in the pathogenesis of scar formation and is a potential target for future molecular‐based adjunctive therapies. The authors hypothesize that interfering RNA (RNAi) can be used to modulate TGF‐β2 production in cultured human respiratory fibroblasts.

Study Design

Basic science.

Setting

Laboratory.

Subjects and Methods

RNAi constructs targeted to the TGF‐β2 transcript were complexed with microsomal lipids and applied to human fibroblasts in cell culture. Transfection efficiency and cell viability were measured by fluorescence microscopy. Messenger RNA (mRNA) for TGF‐β2 was measured 48 hours posttransfection using real‐time quantitative PCR. The quantity of TGF‐β2 protein produced with increasing concentrations of RNAi was measured using enzyme‐linked immunosorbent assay. The function of RNAi‐treated fibroblasts was tested using a wound‐healing assay.

Results

Transfection efficiency of more than 80% was achieved with minimal induced cell death. Treated cells showed selective knockdown of 80% of TGF‐β2 mRNA, which was confirmed with negative controls. As the concentration of RNAi was increased, an incremental decrease in TGF‐β2 protein was measured.

Conclusion

RNAi technology is an effective means of localized and transient gene silencing in cultured human fibroblasts. Transfection can be achieved using microsome complexed RNAi with minimal induced cell death. This preliminary result shows promise for future in vitro studies.
Sacred Sociology
Authors: Turner Charles
Published: May 2011

The writings of Philip Rieff present a challenge to the social sciences along three fronts: the nature of theorizing, the meaning of ‘culture’, and the sources of social order. Here I outline the main themes of his life’s work, including the ‘sacred sociology’ that he announced in his later writings. I suggest that the broad cultural diagnosis that he had developed by the 1960s remains pertinent today, but that his more detailed substantive statements — particularly about art, science, politics and sexuality — are of mixed quality; the reason for this is that, while Rieff developed a very clear view of the meaning and purpose of theorizing, his methods of cultural analysis were less well thought through, and his work haunted by a series of ambivalences that he never resolved, notably between the demands of the critical and the affirmative intellect, and between credal and psychological Jewishness.
Domain-specific treatment effects in children with language and/or working memory impairments: A pilot study
Authors: Wener Sarah E , Archibald Lisa MD
Published: May 2011

This pilot study with an n-of-1 design examined whether children with a specific language impairment without working memory impairment (SLI), a specific working memory impairment without language impairment (SWMI), or mixed language and working memory impairments (L&WMI) may respond differently to treatment targeting verbal or visuospatial strategies. Nine 7- to 9-year-old children (3 SLI, 2 SWMI, 4 L&WMI) completed two 4-week intervention periods focused either on verbal or visuospatial strategies. Three probe tasks were measured throughout all study phases: picture recall, sentence formulation, and geometric puzzle completion. Standardized measures of language and working memory were completed before and after each treatment phase, and 4 months post. Results revealed a domain-specific treatment effect. The verbally-focused treatment resulted in improved performance on the picture recall task whereas the visuospatial focus was associated with positive outcomes on the geometric puzzle probe. Additionally, children with working memory impairment improved on working memory measures while most children with language impairment improved on a grammatical measure.
Between and beyond data: How analogue field experience informs the interpretation of remote data sources in petroleum reservoir geology
Authors: Almklov Petter G. , Hepsø Vidar
Published: May 2011

This paper explores how experience from field trips to geological analogues informs the interpretation of remote data sources in petroleum reservoir geology. It is based on observations of a group of petroleum geologists on a field trip to an analogue field and descriptions of the typical office work of such professionals in the same company. Special attention is given to representational artefacts and data types employed in the different settings. Field trips are experiences in which the geologists develop skills in handling the relationship between geological and physical structures experienced in the field and conventional representations of them. When trying to make sense of the offshore reservoirs deep beneath the seabed, they have to make do with fragmentary data from remote sensor arrangements. When creating integrated ideas of a reservoir based on sparse remote data sources, petroleum geologists draw analogies to the patterns observed in the field and draw from the skills developed when performing similar extrapolations in the field.
Picasso’s migraine: Illusory cubist splitting or illusion?
Authors: Haan Joost , Ferrari Michel D
Published: May 2011

It is widely believed that Pablo Picasso suffered from migraine. The main cause for this is our suggestion made 10 years ago that some of Picasso’s paintings resemble migraine auras. Here we critically look back at our own hypothesis. We conclude that, although the idea is still fascinating, there is no proof of Picasso suffering from migraine with aura.
Differences in sensory processing between chronic cervical zygapophysial joint pain patients with and without cervicogenic headache
Authors: Chua Nicholas H L , van Suijlekom Hans A , Vissers Kris C , Arendt-Nielsen Lars , Wilder-Smith Oliver H
Published: May 2011

Background: It is not known why some patients with underlying chronic nociceptive sources in the neck develop cervicogenic headache (CEH) and why others do not. This quantitative sensory testing (QST) study systematically explores the differences in sensory pain processing in 17 CEH patients with underlying chronic cervical zygapophysial joint pain compared to 10 patients with chronic cervical zygapophysial joint pain but without CEH.

Methods: The QST protocol comprises pressure pain threshold testing, thermal detection threshold testing, electrical pain threshold testing and measurement of descending inhibitory modulation using the conditioned pain modulation (CPM) paradigm.

Results: The main difference between patients with or without CEH was the lateralization of pressure hyperalgesia to the painful side of the head of CEH patients, accompanied by cold as well as warm relative hyperesthesia on the painful side of the head and neck.

Discussion: From this hypothesis-generating study, our results suggest that rostral neuraxial spread of central sensitization, probably to the trigeminal spinal nucleus, plays a major role in the development of CEH.
Is the Fundamental Science of Macroeconomics Sound?
Authors: Colander David
Published: May 2011

Recently, Ben Bernanke has argued that in the events leading up to the financial crisis, mistakes were made, but they were primarily engineering or management mistakes, not mistakes in the fundamental science of macroeconomics, which he sees as sound. This paper argues that Bernanke is wrong and that standard macroeconomics has not recognized, and still does not recognize, the limits of science and of formal modeling when studying something as complex as the macro economy. This failure to recognize, and adequately convey to policy makers, the limits of our scientific understanding of the macro economy, has led standard macroeconomics to combine fundamental science and policy applications in ways that undermine both. This paper advocates a classical methodological approach, which Keynes followed as well, that strictly separates fundamental science from policy analysis. Policy does not directly follow from models; it follows from reasoned analysis which uses models, but which combines models with institutional knowledge, intuition, and common sense.

JEL classification: A11, B22, E0, E60
Macroeconomic Theory After the Crisis
Authors: Dutt Amitava Krishna
Published: May 2011

Mainstream macroeconomic theory, especially as synthesized in the New Neoclassical Synthesis, is argued to have many problematic aspects, problems which have been especially underscored by the recent economic crisis, and which relate to its method, its views of the economy, and its goals and its policy implications. These failings call for greater pluralism in macroeconomic theory and greater acceptance of alternative approaches. One of these—which is based on accounting identities and behavioral and institutional relations, which stresses the importance of uncertainty and power, emphasizes the goals of reducing unemployment and distributional fairness, and views policymaking as an art—is particularly worthy of attention.

JEL classification: B22, B41, E00
Workers’ Participation in Management, Workers’ Control of Production
Authors: Gunn Christopher
Published: May 2011

For several decades workers’ participation in management was a persistent demand of the left. In the neoliberal era it became, in a twisted way, a reality for some workers. Team organization of production, reduction of supervisory staffing, and a constant drive for productivity improvement became the norm, requiring broader managerial involvement by workers in their activities. Workers’ control of production remains on the radical agenda, but with broader implications. Workers’ control of production implies dramatic changes in the relationship between capital and labor, and with them development of alternative forms of production and distribution.

JEL classification: J54, B51, L23
The Role of Workers in Management
Authors: Campbell Al
Published: May 2011

Independent of whatever other advantages it might have for the workers, worker ownership has repeatedly demonstrated in the real world that it is no guarantee for worker participation in management. The participation of workers in management as a first step toward worker self-management requires institutions and practices that will both allow such participation and promote it. This paper considers, in the frame of four standard issues in worker self-management, six specific institutions and practices common to the collection of co-ops that constitute the Mondragón complex that have generated meaningful worker participation in management in this large corporation.

JEL classification: J54, L29, M19
Global Restructuring, Social Distancing, and a Community-Based Worker’s Center Response
Authors: Ji Minsun
Published: May 2011

This paper addresses the impacts of global “social distancing” on employers and workers and examines community-based worker center strategies to mitigate those impacts. Through a case study of El Centro Humanitario, Denver’s human rights center for immigrant day laborers, the paper addresses how community organizations can respond to social distancing by “organizing the unorganized,” and crafting strategies such as worker-owned cooperatives to promote workers’ rights while reconnecting workers to their work and to each other.

JEL classification: L31, L33, P32
Race in Early Tobacco Advertising
Authors: Goldstein Jonathan P.
Published: May 2011

This paper analyzes the inclusion/exclusion and portrayal of minorities (African and Native American) in one early form of tobacco advertising: American tobacco cards from 1880-1911. I test hypotheses related to: 1) attempts to hide the accomplishments/lifestyle of minorities; 2) the inclusion of minorities for exploitative purposes; 3) the role of competition on discrimination; and 4) the existence of progressive undercurrents in this form of advertising. My econometric analysis shows that American tobacco cards contributed via exclusion to the hidden from view treatment of minority lifestyles. The majority of minority inclusions was exploitative in nature promoting racial stereotyping and niche audience marketing, yet a limited progressive undercurrent of treatment, particularly for Native Americans, did emerge.

JEL classification: B500, J150, N310
A Novel Sporadic 614-Kb Duplication of the 22q11.2 Chromosome in a Child With Amyoplasia
Authors: Liewluck Teerin , Sacharow Stephanie J. , Fan YaoShan , Lopez-Alberola Roberto
Published: May 2011

Arthrogryposis is a rare congenital disorder characterized by multiple fixed joint contractures. Decreased fetal movement, regardless of etiology, causes an immobilization of the affected joints and subsequent contractures. Amyoplasia refers to the most common variant of arthrogryposis in which patients develop symmetrical limb contractures because of muscle underdevelopment. It is a sporadic condition with no known genetic abnormality being linked to this syndrome. The authors report a 4-month-old boy with amyoplasia carrying a novel de novo 614-Kb duplication of the 22q11.2 region. Amyoplasia has not been reported in patients with 22q11.2 microduplication syndrome. This particular 614-Kb duplicated segment contains 7 genes located within the typical 22q11.2 duplication region and 2 genes, TUBA8 and USP18, mapping outside of the typical region. This patient broadens the phenotypic spectrum of the 22q11.2 microduplication syndrome and raises the possibility that TUBA8 and USP18 may play an important role in the pathogenesis of amyoplasia.
Complex Regional Pain Syndrome Type 1 in a Child With Migraine
Authors: Ray Munni , Singhi P. D.
Published: May 2011

Complex regional pain syndrome type 1 is a rare painful syndrome in children involving an extremity which consists of pain out of proportion to the cause, loss of function, and significant evidence of autonomic dysfunction. We report a child, a known case of migraine who presented with spontaneous onset pain and sudomotor changes in an extremity not preceded by any trauma. A good clinical eye is required for the identification and diagnosis of this underreported condition to prevent doing extensive investigations. The coexistence of migraine and complex regional pain syndrome type 1 in a patient is interesting and is probably due to the common underlying pathophysiological abnormalities involving central serotonin activity and neurogenic inflammatory mechanisms.
Clinical and Imaging Observations in Isolated Sulfite Oxidase Deficiency
Authors: Bindu Parayil Sankaran , Christopher Rita , Mahadevan Anita , Bharath Rose Dawn
Published: May 2011

Isolated sulfite oxidase deficiency is a rare neurometabolic disorder that closely mimics hypoxic ischemic encephalopathy both clinically and radiologically. Phenotypic and imaging observations in 2 children (aged 14 months and 8 years) with this disease are described. Both had profound mental retardation, microcephaly, spastic quadriparesis, and uncontrolled seizures from the neonatal period. Diagnosis was established by demonstrating the presence of sulfites in urine and genetic analysis. Magnetic resonance imaging of the brain revealed severe cystic leukomalacia, cortical atrophy with ulegyric pattern, and cerebellar hypoplasia that progressed over time in both the patients. Early diagnosis of this devastating disorder will provide an opportunity for genetic counseling and prenatal testing.
Infantile-Onset Disorders of Mitochondrial Replication and Protein Synthesis
Authors: Nogueira Célia , Carrozzo Rosalba , Vilarinho Laura , Santorelli Filippo M.
Published: May 2011

Most inherited mitochondrial diseases in infants result from mutations in nuclear genes encoding proteins with specific functions targeted to the mitochondria rather than primary mutations in the mitochondrial DNA (mtDNA) itself. In the past decade, a growing number of syndromes associated with dysfunction resulting from tissue-specific depletion of mtDNA have been reported in infants. MtDNA depletion syndrome is transmitted as an autosomal recessive trait and causes respiratory chain dysfunction with prominent neurological, muscular, and hepatic involvement. Mendelian diseases characterized by defective mitochondrial protein synthesis and combined respiratory chain defects have also been described in infants and are associated with mutations in nuclear genes that encode components of the translational machinery. In the present work, we reviewed current knowledge of clinical phenotypes, their relative frequency, spectrum of mutations, and possible pathogenic mechanisms responsible for infantile disorders of oxidative metabolism involved in correct mtDNA maintenance and protein production.
Thigh Muscle Volume Measured by Magnetic Resonance Imaging Is Stable Over a 6-Month Interval in Spinal Muscular Atrophy
Authors: Sproule Douglas M. , Montgomery Megan J. , Punyanitya Mark , Shen Wei , Dashnaw Stephen , Montes Jacqueline , Dunaway Sally , Finkel Richard , Darras Basil , Vivo Darryl C. De , Kaufmann Petra
Published: May 2011

Changes in thigh muscle volume over 6 months were assessed using magnetic resonance imaging in 11 subjects aged 6 to 47 years with spinal muscular atrophy (4 type 2 and 7 type 3; 4 ambulatory and 3 nonambulatory). Muscle volume with normal and abnormal signal was measured using blinded, semiautomated analysis of reconstructed data. Volumes at baseline and 6 months were correlated with clinical function at each epoch. There was minimal increase in normal (0.3 ± 1.4 mL/cm) and total (0.1 ± 1.3 mL/cm) muscle. Muscle volume correlated closely with clinical function. Minimal interval change in muscle volume is consistent with the established clinical history of minimal disease progression over intervals shorter than 1 year. Relative constancy of muscle volume estimation and correlation with established functional measures suggest a role for segmental magnetic resonance imaging as a biomarker of treatment effect in future therapeutic trials.
Laboratory and Clinical Correlates for Magnetic Resonance Imaging (MRI) Abnormalities in Pediatric Sickle Cell Anemia
Authors: Lebensburger Jeffrey D. , Hilliard Lee M. , McGrath Tony M. , Fineberg Naomi S. , Howard Thomas H.
Published: May 2011

Children with sickle cell anemia are at risk for brain injury. Physicians obtain brain magnetic resonance imaging (MRI) for clinical indications to determine if a patient has developed a brain injury. Controversy exists whether all children with sickle cell anemia should undergo MRI screening. This retrospective study evaluates the clinical and laboratory correlates for brain injury in 124 MRIs obtained for a variety of clinical indications. Seizure, sensory, or motor events were statistically associated with the highest risk for brain injury while less specific neurologic complaints of headache or poor school performance were not associated. Children with high systolic blood pressure, leukocytosis, and severe anemia demonstrate a higher probability for brain injury. These results indicate that brain MRI should be obtained on all children with seizure, sensory, or motor events. These data suggest that less specific neurologic symptoms should be screened if physical findings or abnormal lab or vital signs exist.
Focal Central White Matter Lesions in Alexander Disease
Authors: Barreau Pauline , Prust Morgan J. , Crane Jeremy , Loewenstein Johanna , Kadom Nadja , Vanderver Adeline
Published: May 2011

Alexander disease is a neurodegenerative disorder of the central white matter caused by dominant mutations in GFAP, the gene encoding glial fibrillary acidic protein. Magnetic resonance imaging pattern recognition studies have established characteristic radiologic phenotypes for this disorder. In some cases, however, genetically confirmed cases do not express these features, and several reports have identified “atypical” radiologic findings in Alexander disease patients. Here, the authors report 3 genetically confirmed Alexander disease cases with focal central white matter lesions that, upon longitudinal clinical and radiologic evaluation, appear to reflect an atypical Alexander disease magnetic resonance imaging phenotype and not another pathophysiologic process such as encephalitis, infarction, or neoplasm.
The Effect of Recurrent Severe Hypoglycemia on Cognitive Performance in Children With Type 1 Diabetes
Authors: Blasetti Annalisa , Chiuri Rosa Maria , Tocco Anna Maria , Giulio Concetta Di , Mattei Peter A. , Ballone Enzo , Chiarelli Francesco , Verrotti Alberto
Published: May 2011

The purpose of this study was to investigate the existence and extent of cognitive impairment in type 1 diabetic children with episodes of recurrent severe hypoglycemia, using meta-analysis to synthesize data across studies. The meta-analysis sample included: 441 children with diabetes and recurrent severe hypoglycemia, 560 children with diabetes and without recurrent severe hypoglycemia. Overall, children with type 1 diabetes and recurrent severe hypoglycemia had slightly lower performance than diabetic children without severe hypoglycemia, only in some cognitive domains: intelligence, memory, learning, and verbal fluency/language. Greater impairment was found in memory and learning. No impairment was found for motor speed. Our results seem to confirm the hypothesis that recurrent severe hypoglycemia has a selective negative effect on the children’s cognitive functions. However, these results must be considered with caution taking into account factors such as small sample sizes, the different definitions of severe hypoglycemia, and the variety of neuropsychological tests used.
Hyponatremia and the Use of Vasopressin Receptor Antagonists In Critically Ill Patients
Authors: Lehrich Ruediger W. , Greenberg Arthur
Published: May 2011

Hyponatremia in critically ill patients is a common and challenging problem. Increased levels of arginine vasopressin almost always contribute to the etiology. Inhibition of the vasopressin receptor with a vasopressin receptor antagonist (vaptan) is a novel approach to the treatment of hyponatremia. Vaptans are well suited to the treatment of chronic hyponatremia associated with syndrome of inappropriate anti-diuretic hormone secretion (SIADH) and hypervolemic states like cirrhosis or congestive heart failure. No data are available on the use of vaptans in acute hyponatremia, and they are not indicated in hypovolemic hyponatremia. The focus of this review is the treatment of critically ill patients with hyponatremia with vaptans and other measures.
Why Diversity Became Orthodox in Higher Education, and How it Changed the Meaning of Race on Campus
Authors: Berrey Ellen C.
Published: May 2011

Using qualitative data about University of Michigan between 1965 and 2005, this article shows how administrators’ diversity discourse and programs have defined race as a cultural identity, expressed through interaction, which provides instrumental benefits. It also explains three major reasons why, starting in the mid-1980s, university administrators adopted this racial orthodoxy of “diversity”: to signal compliance with—and also to redefine—law and institutional norms while still practicing race-based affirmative admissions; to frame inclusion in more complex terms than a racial binary or numerical representation amidst growing campus multiculturalism; and to market the university, especially to white students. The article advances racial formation theory by developing the concept of a racial orthodoxy. It shows that diversity discourse and programs have sometimes advanced the goal of racial minority inclusion, but at the cost of downplaying problems of racial inequality and misrepresenting racial minorities’ campus experiences.
Comparison of shape memory polyurethanes and polyurethane-ureas having crystalline reversible phase
Authors: Ji Feng Long , Hu Jin Lian
Published: May 2011

Shape memory polyurethanes (SMPUs) have been extensively investigated but shape memory polyurethane-ureas (SMPUUs) with aromatic diamines as chain extenders have been rarely reported. In the present study, a series of SMPUs and SMPUUs having crystalline reversible phase were prepared. The shape memory properties including shape recovery, shape fixity and recovery stress of the SMPUs and the SMPUUs were compared systematically. When hard-segment content (HSC) was 30% the polyurethane-urea exhibited higher shape recovery than its polyurethane analogue. With the increase of HSC the shape recoveries of both the SMPUs and the SMPUUs decreased but those of the SMPUUs decreased more apparently. When HSC was 40%, the shape recovery of the polyurethane-urea was lower than that of the polyurethane. This is because the great increase of physical cross-linking density of SMPUUs resulted in significant increase of irreversible deformation. In comparison with those of the SMPUs, the shape recovery curves of SMPUUs shift to lower temperatures. This is because the higher physical cross-link density of the SMPUUs results in more decrease of the melting temperature of soft phase. Moreover, the shape fixities of the SMPUUs were lower than those of the SMPUs with identical HSC also because of their higher physical cross-link density. The recovery stresses of the SMPUs and the SMPUUs increased with the increase of HSC. The recovery stress of a polyurethane-urea was higher than that of its polyurethane analogue by over 100%. Hence it is possible to produce SMPUUs with much larger recovery stress and higher shape recovery without sacrificing much shape fixity by controlling appropriate HSC.
Modelling diesel engines with a variable-geometry turbocharger and exhaust gas recirculation by optimization of model parameters for capturing non-linear system dynamics
Authors: Wahlström J , Eriksson L
Published: May 2011

A mean-value model of a diesel engine with a variable-geometry turbocharger (VGT) and exhaust gas recirculation (EGR) is developed, parameterized, and validated. The intended model applications are system analysis, simulation, and development of model-based control systems. The goal is to construct a model that describes the gas flow dynamics including the dynamics in the manifold pressures, turbocharger, EGR, and actuators with few states in order to obtain short simulation times. An investigation of model complexity and descriptive capabilities is performed, resulting in a model that has only eight states. A Simulink implementation including a complete set of parameters of the model are available for download. To tune and validate the model, stationary and dynamic measurements have been performed in an engine laboratory. All the model parameters are estimated automatically using weighted least-squares optimization and it is shown that it is important to tune both the submodels and the complete model and not only the submodels or not only the complete model. In static and dynamic validations of the entire model, it is shown that the mean relative errors are 5.8 per cent or lower for all measured variables. The validations also show that the proposed model captures the system properties that are important for control design, i.e. a non-minimum phase behaviour in the channel EGR valve to the intake manifold pressure and a non-minimum phase behaviour, an overshoot, and a sign reversal in the VGT to the compressor mass flow channel, as well as couplings between channels.
An assessment of the robustness of gauge repeatability and reproducibility analysis in automotive components
Authors: Osma A
Published: May 2011

Measurement system analysis is a vital component of many continuous improvement initiatives. In the manufacturing industry, variation in a measurement system is a key characteristic to be assessed and improved upon. Measurement systems are commonly evaluated by performing a gauge repeatability and reproducibility (gauge R&R) study, which analyses any variations between measurements by a gauge (repeatability) and between results obtained by different appraisers (reproducibility). To determine the preferred method for gauge R&R analysis; average and range, and two-way analysis of variance were applied to data taken from four real case studies from the automotive industry (a stabilizer clamp bracket, a coated steel sheet, a steel sheet body panel, and a brake disc). Possible differences in gauge R&R characteristics were compared, and residual diagnosis was used to discern violations in two-way ANOVA. To develop a robust road map for gauge R&R analysis, interactions between gauge R&R parameters, residual diagnosis, and number of distinct categories were analysed.
Comparisons of the simulated emissions and fuel efficiencies of diesel and gasoline hybrid electric vehicles
Authors: Gao Z , Chakravarthy V K , Daw C S
Published: May 2011

This paper presents results from gasoline- and diesel-powered hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) that account for the interaction of drive cycle transients and engine start–stop events with after-treatment devices and their associated fuel penalties. These simulations were conducted using the Powertrain Systems Analysis Toolkit software combined with after-treatment component models developed at Oak Ridge National Laboratory. The present authors employed a three-way catalyst model for gasoline emissions control and a lean nitrogen oxide (NO x) trap model to simulate diesel exhaust NO x reduction. A previously reported methodology based on experimentally calibrated corrections to steady state maps was used to simulate engine-out emissions and thermal variations. As expected, the simulations indicate a higher baseline fuel efficiency for diesel-powered hybrid vehicles, but this advantage is reduced by about a third for both HEVs and PHEVs when the fuel penalty for the lean NO x trap is included. These preliminary studies demonstrate that existing engine and exhaust systems models can capture important features of the highly transient engine operation in hybrid vehicles and can provide useful comparisons between advanced hybrid vehicle engine options.
Review of data mining for multi-disciplinary design optimization
Authors: Jeong S , Shimoyama K
Published: May 2011

One of the difficulties in multi-disciplinary design optimization lies in the complicated interactions between large numbers of objective functions, design variables, and constraints. This difficulty often leads to an unsuitable formulation of design problems. Data mining is often used to address these challenges. Data mining provides insight into the design of complicated systems. The information obtained from data mining can be used to support (a) formulation of design problems, (b) decision making, and (c) design steering. This report presents a review of recent developments and applications of data mining techniques in the engineering design field, and introduces real-world examples of state-of-the-art data mining techniques.
Information literacy, learning, and the public library: A study of Danish high school students
Authors: Nielsen Bo Gerner , Borlund Pia
Published: May 2011

The paper reports on a study of 12 Danish high school students’ perceptions of public libraries’ role in learning, user education, information literacy, and librarians’ information competencies. The study is undertaken by use of literature review and interviews with a purposive select sample of public library users in Denmark. The study demonstrates that public libraries are considered an important place for learning. The high school students view the public librarians as very competent and as good at helping them to develop their information needs, identify sources, and support the students in the information search processes. The high school students show rather good critical skills, but poor information need developing skills. The study further shows that concepts of information literacy and lifelong learning are not very well understood by the users, i.e. the high school students. The results have a range of implications, both for pedagogical praxis in the public library and for Library and Information Science (LIS).
Are Universities Creating Millennial Narcissistic Employees? An Empirical Examination of Narcissism in Business Students and Its Implications
Authors: Westerman James W. , Bergman Jacqueline Z. , Bergman Shawn M. , Daly Joseph P.
Published: May 2011

The authors investigate whether narcissism levels are significantly higher in undergraduate business students than psychology students, whether business schools are reinforcing narcissism in the classroom, and whether narcissism is influencing student salary and career expectations. Data were collected from Millennial students ( n = 536) and faculty at an AACSB-accredited comprehensive state university. Results indicate that the current generation of college students has significantly higher levels of narcissism than college students of the past, business students possess significantly higher levels of narcissism than psychology students, narcissism does not have a significant (positive or negative) relationship with business school classroom outcomes, and narcissists expect to have significantly more career success in terms of ease of finding a job, salary, and promotions. Considering the well-documented and profoundly negative implications of narcissism for workplace environments, this finding suggests a need for future research on the impact of increasing student narcissism in business students and on successful intervention strategies.
Understanding the Sociostructural Correlates of Terrorism in Turkey
Authors: Akyuz Kadir , Armstrong Todd
Published: May 2011

Social disorganization theory was used to frame a test of the sociostructural correlates of terrorism across 81 provinces in Turkey. Zero-inflated negative binomial regression (ZINB) models were used to estimate the relationship between terrorism and poverty, residential mobility, and ethnic heterogeneity. Initial regression models found that measures of poverty and residential mobility were predictive of terrorism. Subsequent models found ethnic heterogeneity was predictive of terrorism, while controlling for the influence of poverty and residential mobility.
A Five-Factor Measure of Schizotypal Personality Traits
Authors: Edmundson Maryanne , Lynam Donald R. , Miller Joshua D. , Gore Whitney L. , Widiger Thomas A.
Published: May 2011

The current study provides convergent, discriminant, and incremental validity data for a new measure of schizotypy from the perspective of the five-factor model (FFM) of general personality structure. Nine schizotypy scales were constructed as maladaptive variants of respective facets of the FFM (e.g., Aberrant Ideas as a maladaptive variant of FFM Openness to Ideas). On the basis of data from 143 undergraduates, the convergent validity of these nine scales was tested with respect to seven established measures of schizotypy and the respective facets of the FFM. Discriminant validity was tested with respect to facets from other FFM domains and components of schizotypy. Incremental validity was tested with respect to the ability of the FFM schizotypy scales to account for variance in two established measures of schizotypy, after variance accounted for by respective FFM facets and other established measures of schizotypy were first removed. The findings support the validity of these new scales as measures of schizotypal traits and as maladaptive variants of the FFM.
The Measurement of Boredom
Authors: Mercer-Lynn Kimberley B. , Flora David B. , Fahlman Shelley A. , Eastwood John D.
Published: May 2011

There are two commonly used measures of boredom: the Boredom Proneness Scale (BPS) and the Boredom Susceptibility Scale (ZBS). Although both were designed to measure the propensity to experience boredom (i.e., trait boredom), there are reasons to think they may not measure the same construct. The present research sought to evaluate this proposition in several stages. Specifically, relationships between the BPS, ZBS, and important causal (Study 1, N = 837), correlational (Study 2, N = 233), and outcome variables (Study 3, N = 137) were examined in university students. Taken together, results support the notion that the BPS and ZBS do not measure the same construct. Specifically, higher BPS scores were associated with higher levels of neuroticism, experiential avoidance, attentional and nonplanning impulsivity, anxiety, depression, dysphoria, and emotional eating. Conversely, higher ZBS scores were associated with higher levels of motor impulsivity, sensitivity to reward, gambling, and alcohol use and lower levels of neuroticism, experiential avoidance, and sensitivity to punishment.
Exceptional Abilities in the Spatial Representation of Numbers and Time
Authors: Kadosh Roi Cohen , Gertner Limor , Terhune Devin Blair
Published: May 2011

In the study of basic and high-level cognitive functions, neuroscientists, psychologists, and philosophers have tended to focus on normal psychological processes and on deficits in these processes, whereas the study of exceptional abilities has been largely neglected. Here the authors emphasize the value of researching exceptional abilities. They make the case that studies of exceptional representations, such as of time, number, and space in synesthesia, can provide us with insights regarding the nature of the neurocognitive mechanisms of these dimensions, as well as their developmental, evolutionary, and cultural origins.
Cyclosporine A, 2.5 mg/kg, Does Not Reduce Myocardial Infarct Size in a Porcine Model of Ischemia and Reperfusion
Authors: Karlsson Lars O. , Bergh Niklas , Grip Lars
Published: May 2011

Background: In recent years, cyclosporine A (CsA) has emerged as a promising therapy to limit myocardial ischemic–reperfusion injury, presumably by inhibiting the opening of the mitochondrial permeability transition pore. Results from different large animal models are conflicting, however, with failure to prove beneficial effects of 10 mg/kg CsA administered at reperfusion. Recently, a small clinical study using a bolus of 2.5 mg/kg CsA showed promising but not unequivocal results. The aim of the present study was to estimate the magnitude of a possible infarct reduction with the use of the latter regimen in a closed-chest porcine model for ischemia and reperfusion. Materials and Methods: Pigs underwent catheterization with balloon occlusion of the left descending coronary artery for 40 minutes, followed by reperfusion for 4 hours. They were randomized to receive an intravenous bolus 7 minutes before reperfusion of either 2.5 mg/kg CsA (n = 12) or saline (control, n = 11). Hearts were stained to quantify area at risk and infarct size. Results: Throughout the experiment, there were no differences between the groups in baseline characteristics or hemodynamic variables. CsA treatment did not reduce infarct size as a proportion of area at risk compared with control (51% ± 6% and 54% ± 6%, respectively, P = .75). Conclusion: In a closed-chest porcine model for myocardial ischemia and reperfusion injury, 2.5 mg/kg CsA administered before reperfusion did not reduce infarct size.
Preventing Sexual Aggression Among College Men: An Evaluation of a Social Norms and Bystander Intervention Program
Authors: Gidycz Christine A. , Orchowski Lindsay M. , Berkowitz Alan D.
Published: May 2011

Men and women living in randomly selected 1st-year dormitories participated in tailored single-sex sexual assault prevention or risk-reduction programs, respectively. An evaluation of the men’s project is presented ( N = 635). The program incorporated social norms and bystander intervention education and had an impact on self-reported sexual aggression and an effect on men’s perceptions that their peers would intervene when they encountered inappropriate behavior in others. Relative to the control group, participants also reported less reinforcement for engaging in sexually aggressive behavior, reported fewer associations with sexually aggressive peers, and indicated less exposure to sexually explicit media.
The Men’s Program: Does It Impact College Men’s Self-Reported Bystander Efficacy and Willingness to Intervene?
Authors: Langhinrichsen-Rohling Jennifer , Foubert John D. , Brasfield Hope M. , Hill Brent , Shelley-Tremblay Shannon
Published: May 2011

This study considered whether a rape prevention program could reduce men’s rape myth acceptance, enhance the perceived effectiveness of college men’s bystander behavior, and increase men’s willingness to intervene as bystanders in potentially dangerous situations. As predicted, college men who experienced The Men’s Program significantly increased their self-reported willingness to help as a bystander and their perceived bystander efficacy in comparison to college men who experienced the comparison condition. Men’s Program participants also significantly decreased their self-reported rape myth acceptance in comparison with comparison condition participants. The college policy and rape prevention program planning implications of these findings are discussed.
Mechanics of membrane–membrane adhesion
Authors: Agrawal Ashutosh
Published: May 2011

Curvature elasticity is used to derive the equilibrium conditions that govern the mechanics of membrane–membrane adhesion. These include the Euler–Lagrange equations and the interface conditions which are derived here for the most general class of strain energies permissible for fluid surfaces. The theory is specialized for homogeneous membranes with quadratic ‘Helfrich’-type energies with non-uniform spontaneous curvatures. The results are employed to solve four-point boundary value problems that simulate the equilibrium shapes of lipid vesicles that adhere to each other. Numerical studies are conducted to investigate the effect of relative sizes, osmotic pressures, and adhesion-induced spontaneous curvature on the morphology of adhered vesicles.
Could Polyunsaturated Fatty Acids Deficiency Explain Some Dysfunctions Found in ADHD? Hypotheses From Animal Research
Authors: Transler Catherine , Mitchell Siobhan , Eilander Ans
Published: May 2011

Objectives: The objective is to evaluate possible mechanisms explaining the link between polyunsaturated fatty acid (PUFA) deficiencies and ADHD, based on findings from animal research. Method: The authors consulted peer-reviewed publications from the last 10 years (Medline and resulting reference lists). Results: PUFA deficiency in rodents results in behavioral changes (increased motor activity and decreased learning abilities) and dysregulations of monoamine neurotransmission. Behavioral improvement following a PUFA recovery diet is observed, but recovery of brain monoamine dysregulation is not fully demonstrated. Anti-inflammatory processes could damage neural membranes, but the direct link with ADHD model is not documented. Synaptic growth and neurogenesis impairment could account for working memory dysregulations, but research is at its early start. Conclusion: Induced PUFA deficiencies in animals show several noteworthy similarities with brain dysregulations seen in ADHD human children. However, the mechanisms of partial recovery after PUFA supplementation are not fully understood, and rigorous clinical trials have yet to show PUFA supplementation is an effective complementary treatment for ADHD.