bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of nonsteroidal anti‐inflammatory drugs and analgesics by liver transplant recipients
Authors: Mulka‐Gierek Maria , Foroncewicz Bartosz , Florczak Michał , Pączek Leszek , Krawczyk Marek , Mucha Krzysztof
Published: February 2016

Aims and objectives

This study aimed to assess the reasons and the frequency of the use of over‐the‐counter (OTC) nonsteroidal anti‐inflammatory drugs (NSAIDs) or analgesics by liver transplant recipients (LTR). Patient awareness of possible drug‐related side‐effects was also assessed.

Background

NSAIDs and analgesics available without prescription belong to the most commonly used class of drugs. However, use of these drugs might be complicated by toxic adverse effects (AEs). Patients at risk for AEs include the transplant recipients.

Design/methods

This was a descriptive study. An anonymous survey was carried out in 73 randomly selected LTR, who represented 10% of all LTR at our centre.

Results

There were 64% of the patients who confirmed taking NSAIDs or analgesics; 16% of these patients took these drugs at least several times a week and 10% took them daily. For 39% of patients, the only way to manage their pain were OTC NSAIDs or analgesics. As many as 36% of patients were unaware of the risks associated with the use of these drugs. Ninety per cent of LTR consider physicians the most trusted source of drugs information.

Conclusions

Our study shows that two‐thirds of LTR take OTC NSAIDs or analgesics and one‐third are unaware of the AEs associated with these drugs. Therefore, both transplant nurses and doctors should educate their patients about the use and possible AE of these drugs.

Relevance to clinical practice

Considering the high NSAIDs consumption rates, the side effects of these drugs should always be suspected. Especially in patients taking these drugs and referring to medical advisors with specific symptoms, such as: abdominal pain, anaemia, elevated serum creatinine concentration or liver enzymes activity. Awareness of the scale of the problem enables health professionals to cooperate in educating patients. Such practices may reduce uncontrolled abuse of these drugs and related health care costs.
Difficulties in using interpreters in clinical encounters as experienced by immigrants living in Sweden
Authors: Krupic Ferid , Hellström Mikael , Biscevic Mirza , Sadic Sahmir , Fatahi Nabi
Published: February 2016

Aims and objectives

To study a group of immigrants' experiences regarding interactions with primary health care through an interpreter.

Background

Approximately, 230 million people are resettled outside of their own home country. Thus, more than 3% of the world's population are migrants. It is a major challenge for health care providers to satisfy immigrants' needs for individualised health care services.

Design

Qualitative study.

Methods

Focus group interviews were conducted with four groups of immigrants (n = 24) from Bosnia and Herzegovina, Croatia, Kosovo and Somalia. The group interviews were audio recorded, transcribed and analysed, and the text was categorised using the content analysis method.

Results

Participants′ expectations of the interpreter‐mediated consultations were high, but not always fulfilled. Interpreters being late, lacking professionalism or lacking knowledge in medical terminology and the use of health care professionals or relatives as interpreters were some of the problems raised.

Conclusion

A well‐organised, disciplined interpreter service with professional and competent interpreters is needed to overcome problems regarding clinical consultations involving interpreters. A satisfactory language bridge has a significant impact on the quality of communications.

Clinical implication

Interpreter services should be well organised, and interpreters should be linguistically, culturally and socially competent, as these factors may have a significant impact on consultation outcomes. Using relatives or staff as interpreters can sometimes be a solution but often results in an unsatisfactory clinical consultation.
Does the Medicare Part D Decision‐Making Experience Differ by Rural/Urban Location?
Authors: Henning‐Smith Carrie , Casey Michelle , Moscovice Ira
Published: February 2016

Purpose

Although much has been written about Medicare Part D enrollment, much less is known about beneficiaries’ personal experiences with choosing a Part D plan, especially among rural residents. This study sought to address this gap by examining geographic differences in Part D enrollees’ perceptions of the plan decision‐making process, including their confidence in their choice, their knowledge about the program, and their satisfaction with available information.

Methods

We used data from the 2012 Medicare Current Beneficiary Survey and included adults ages 65 and older who were enrolled in Part D at the time of the survey (n = 3,706). We used ordered logistic regression to model 4 outcomes based on beneficiaries’ perceptions of the Part D decision‐making and enrollment process, first accounting only for differences by rurality, then adjusting for sociodemographic, health, and coverage characteristics.

Findings

Overall, half of all beneficiaries were not very confident in their Part D knowledge. Rural beneficiaries had lower odds of being confident in the plan they chose and in being satisfied with the amount of information available to them during the decision‐making process. After adjusting for all covariates, micropolitan residents continued to have lower odds of being confident in the plan that they chose.

Conclusions

Policy‐makers should pay particular attention to making information about Part D easily accessible for all beneficiaries and to addressing unique barriers that rural residents have in accessing information while making decisions, such as reduced Internet availability. Furthermore, confidence in the decision‐making process may be improved by simplifying the Part D program.
Dietary restrictions, bone density, and bone quality
Authors: Huang Tsang‐hai , Ables Gene P.
Published: February 2016

Caloric restriction (CR), protein restriction (PR), and specific amino acid restriction (e.g., methionine restriction (MR)) are different dietary interventions that have been confirmed with regard to their comprehensive benefits to metabolism and health. Based on bone densitometric measurements, weight loss induced by dietary restriction is known to be accompanied by reduced areal bone mineral density, bone mass, and/or bone size, and it is considered harmful to bone health. However, because of technological advancements in bone densitometric instruments (e.g., high‐resolution X‐ray tomography), dietary restrictions have been found to cause a reduction in bone mass/size rather than volumetric bone mineral density. Furthermore, when considering bone quality, bone health consists of diverse indices that cannot be fully represented by densitometric measurements alone. Indeed, there is evidence that moderate dietary restrictions do not impair intrinsic bone material properties, despite the reduction in whole‐bone strength because of a smaller bone size. In the present review, we integrate research evidence from traditional densitometric measurements, metabolic status assays (e.g., energy metabolism, oxidative stresses, and inflammatory responses), and biomaterial analyses to provide revised conclusions regarding the effects of CR, PR, and MR on the skeleton.
Interactions of individual perceived barriers and neighbourhood destinations with obesity‐related behaviours in Europe
Authors: Mackenbach J. D. , Lakerveld J. , Van Lenthe F. J. , Teixeira P. J. , Compernolle S. , De Bourdeaudhuij I. , Charreire H. , Oppert J.‐M. , Bárdos H. , Glonti K. , Rutter H. , McKee M. , Nijpels G. , Brug J.
Published: February 2016

Perceived barriers towards physical activity and healthy eating as well as local availability of opportunities (destinations in the neighbourhood) are important determinants of obesity‐related behaviours in adults. Little is known, however, about how these factors interact with the behaviours.

Data were analysed from 5,205 participants of the SPOTLIGHT survey, conducted in 60 neighbourhoods in urban regions of five different countries across Europe. A virtual audit was conducted to collect data on the presence of destinations in each neighbourhood. Direct associations of, and interactions between, the number of individual perceived barriers and presence of destinations with obesity‐related behaviours (physical activity and dietary behaviours) were analysed using multilevel regression analyses, adjusted for key covariates.

Perceiving more individual barriers towards physical activity and healthy eating was associated with lower odds of physical activity and healthy eating. The presence of destinations such as bicycle lanes, parks and supermarkets was associated with higher levels of physical activity and healthier dietary behaviours. Analyses of additive interaction terms suggested that the interaction of destinations and barriers was competitive, such that the presence of destinations influenced obesity‐related behaviours most among those perceiving more barriers.

These explorative findings emphasize the interest and importance of combining objective (e.g. virtual neighbourhood audit) methods and subjective (e.g. individual perceived barriers collected in a survey) to better understand how the characteristics of the residential built environment can shape obesity‐related behaviours depending on individual characteristics. © 2015 World Obesity
Neighbourhood typology based on virtual audit of environmental obesogenic characteristics
Authors: Feuillet T. , Charreire H. , Roda C. , Ben Rebah M. , Mackenbach J. D. , Compernolle S. , Glonti K. , Bárdos H. , Rutter H. , De Bourdeaudhuij I. , McKee M. , Brug J. , Lakerveld J. , Oppert J.‐M.
Published: February 2016

Virtual audit (using tools such as Google Street View) can help assess multiple characteristics of the physical environment. This exposure assessment can then be associated with health outcomes such as obesity. Strengths of virtual audit include collection of large amount of data, from various geographical contexts, following standard protocols. Using data from a virtual audit of obesity‐related features carried out in five urban European regions, the current study aimed to (i) describe this international virtual audit dataset and (ii) identify neighbourhood patterns that can synthesize the complexity of such data and compare patterns across regions. Data were obtained from 4,486 street segments across urban regions in Belgium, France, Hungary, the Netherlands and the UK. We used multiple factor analysis and hierarchical clustering on principal components to build a typology of neighbourhoods and to identify similar/dissimilar neighbourhoods, regardless of region. Four neighbourhood clusters emerged, which differed in terms of food environment, recreational facilities and active mobility features, i.e. the three indicators derived from factor analysis. Clusters were unequally distributed across urban regions. Neighbourhoods mostly characterized by a high level of outdoor recreational facilities were predominantly located in Greater London, whereas neighbourhoods characterized by high urban density and large amounts of food outlets were mostly located in Paris. Neighbourhoods in the Randstad conurbation, Ghent and Budapest appeared to be very similar, characterized by relatively lower residential densities, greener areas and a very low percentage of streets offering food and recreational facility items. These results provide multidimensional constructs of obesogenic characteristics that may help target at‐risk neighbourhoods more effectively than isolated features.
The child and adolescent with HIV in resource poor countries
Authors: Yengopal V , Kolisa Y , Thekiso MD , Molete MP
Published: February 2016

Although sub‐Saharan Africa caries the burden of paediatric and adult HIV/AIDS infections, the epidemic is spreading most rapidly in the Middle East and North Africa Region where between 2005 and 2013, AIDS‐related deaths increased by 66% in comparison with a worldwide fall of 35%. For the first time, in 2011, more than half of people in need of antiretroviral drugs were receiving them, with coverage reaching 54%; yet only 28% of children have access to HIV treatment. This review sought to provide an update of paediatric and adolescent oral HIV/AIDS issues in resource poor countries.

Objectives

To review the literature on paediatric & adolescent HIV with a focus on oral lesions as predictors of HIV infection; as markers of the efficacy of HAART and quality of life; caries risk; management of oral lesions; and epidemiological tests for clinical significance of oral lesions.

Methods

A search strategy was developed for PubMed to identify papers on paediatric oral HIV. Publications in English were selected on the basis that their titles and abstracts were relevant to the review objectives. The reference lists of included papers were screened for additional articles. The time‐search for publications was limited from 2009 to 15 October 2014.

Results

Papers on the prevalence of oral lesions lacked standardization in diagnostic criteria and the introduction of HAART had significantly reduced prevalence; oral lesions remain useful predictors for HIV infection and as markers for the efficacy of HAART. Evidence suggest that caries risk is increased with HIV infection; management of oral lesions is inconsistent with available resources and surprisingly little recent information has been published in the past 5 years. Revised case definitions are proposed for large‐scale epidemiologic studies with the development of an oral lesion index showing promise. Oral health quality of life indicators for children and adolescents are becoming important as more of these indicators are being developed and their negative oral impacts in individuals with oral lesions are now well established.

Conclusions

Paediatric and adolescent oral HIV research needs to be prioritized as current studies are few and are characterized by poor quality study designs, small study samples and a lack of multicentre collaborations. There is a lack of high quality evidence for a number of interventions available for management of oral lesions.
Karl Kraus on Stage
Authors: Martens Gunther
Published: February 2016

Little attention has been paid to Karl Kraus's performance as a public speaker. While his poetics and his contemporaries tell us wildly divergent stories of how he shaped a larger‐than‐life public persona as a cantankerous and infallible moral authority, this article proposes to take a look at the media that were involved in Kraus's staging of his polemical satires. These media include not only recording techniques, but also a specific rhetorical habitus influenced by traditions of pronunciation. In a second step, we discuss the political and intercultural ramifications of Kraus's spoken‐word performance by comparing it with Thomas Mann's speeches. This double outlook allows us to see to what extent Kraus's strong scenic strategy anticipates anti‐illusionistic directing strategies.
„Mag dies ein Illusionismus sein…“
Authors: Philipsen Bart , Rys Michiel
Published: February 2016

Stefan Zweig hielt 1932 in Florenz eine Rede, in der er sich über die aktuelle Idee einer von ihm erwünschten europäischen Einheit äußerte. Anhand eines die ganze Kulturgeschichte umfassenden historischen Abrisses und eines zum Teil auf Freud rekurrierenden kulturpsycho(patho)logischen Vokabulars untermauert Zweig in „Der europäische Gedanke in seiner historischen Entwicklung“ seine zentrale These. Die Rede entspricht dem politischen Selbstverständnis Zweigs und zeugt von einem Krisenbewusstsein, das aus einem Konflikt von Ideal (europäischem Kosmopolitismus bzw. Übernationalismus) und politisch‐gesellschaftlicher Wirklichkeit (nationalistischen Tendenzen) hervorgeht. Zweigs Rede bringt mythische, historische, künstlerisch‐ästhetische und technisch‐wissenschaftliche Diskurse in ein spannungsreiches dialektisches und interdiskursives Verhältnis. Die interdiskursive Literarität macht plausibel, dass die im Vortragstext offensichtlich vorhandenen rhetorischen Spannungen bei einer ersten Lektüre oder einem Zuhören unbemerkt bleiben. Der Beitrag will aber solche rhetorischen Strategien und Widersprüche aufdecken, um auf diese Weise die literarische Komplexität dieser spezifischen Rede hervorzuheben; es soll dargelegt werden, wie der Redner die spezifische kommunikative Situation eines Vortrags ausnutzt, um seine nicht immer konsistenten Argumente zu entwickeln.
The Use of Ultrasound to Improve Axillary Vein Access and Minimize Complications during Pacemaker Implantation
Authors: ESMAIEL ABDULLAH , HASSAN JEREMY , BLENKHORN FAY , MARDIGYAN VARTAN
Published: February 2016

Background

The Agency for Healthcare Research and Quality in the United States recommends the use of ultrasound (US) for central venous access to improve patient outcomes. However, in a recent publication, US is still underutilized for axillary vein access during pacemaker implantation.

Objective

We sought to describe a technique for US‐guided axillary vein access during pacemaker implantation and to report complication rates and success rate.

Methods

Retrospective data collection included success rate and complications on all pacemaker implants by one operator since implementing the systematic use of US at our institution, from November 2012 to January 2015. For the last 59 cases, data were collected prospectively to include time of venous access and number of attempts.

Results

A total of 403 consecutive patients were included in the analysis. Two leads were implanted in 255 cases and one lead was implanted in 148 cases. The rate of successful US‐guided access was 99.25%. There were no access‐related complications. The average number of venipuncture attempts was 1.18 per patient. The average time to obtain venous access was 2.24 minutes including the time to apply the sterile US sleeve.

Conclusion

The described technique has the potential to improve the success rate of axillary vein access and minimize complications during pacemaker implantation.
The Relationships Between Parasympathetic Function and Pain Perception: The Role of Anxiety
Authors: Nahman‐Averbuch Hadas , Sprecher Elliot , Jacob Giris , Yarnitsky David
Published: February 2016

Background

Previous studies have identified relationships between autonomic function and pain perception. Anxiety was found to influence both autonomic and pain responses. We examined the effect of anxiety level on parasympathetic function and pain perception as well as on the relationships between these 2 systems.

Methods

Thirty healthy females were divided into high‐ and low‐anxiety groups according to their trait anxiety levels. Parasympathetic function was obtained using heart rate variability, deep breathing, and Valsalva ratios. Pain perception parameters of heat pain thresholds, pain rating of supra‐thresholds stimulus, mechanical temporal summation, and conditioned pain modulation response were examined.

Results

The low‐anxiety and high‐anxiety groups exhibited no significant differences in the parasympathetic function and pain perception parameters. Assessment of the associations revealed that in the high‐anxiety group, higher mean ratings of the tonic heat pain stimulus were significantly correlated with higher rMSSD (r2 = 0.358, P = 0.019), but this was not found for the low‐anxiety group (P = 0.282). In addition, in the high‐anxiety group, efficient conditioned pain modulation response was correlated with higher deep breathing ratio (r2 = 0.363, P = 0.023); however, in the low‐anxiety group, the correlation did not reach significance (P = 0.109).

Conclusions

This study demonstrates the role of anxiety level on the relationships between parasympathetic function and pain perception. We suggest that a situation of high anxiety leads to higher norepinephrine levels that can influence both parasympathetic function and pain perception, thus explaining the significant relationships found between these 2 systems only in subjects with high anxiety.
Dynamic Mechanical Allodynia—One Clinical Sign, Several Mechanisms: Five Illustrative Cases
Authors: Buonocore Michelangelo , Demartini Laura , Aloisi Anna Maria , Bonezzi Cesare
Published: February 2016

Pain evoked by tangential movement across the skin is usually defined as dynamic mechanical allodynia (DMA). Some patients complain of DMA as troublesome as spontaneous pain and refer a marked interfering with activities of daily living and sleep. Pathophysiology of DMA is complex and can be related to several mechanisms, both nociceptive and neuropathic. Five exemplificative clinical cases of DMA are presented, each associated to a possible specific mechanism: injured skin DMA, peri‐injured skin DMA, far injury DMA, nerve‐confined DMA and fear DMA (pseudo allodynia). The identification of these subcategories of DMA can stimulate further studies aimed at evaluating the usefulness of a mechanism‐based therapy for the different clinical forms of DMA.
Understanding Local Policy Elites’ Perceptions on the Benefits and Risks Associated with High‐Voltage Power Line Installations in the State of Arkansas
Authors: Moyer Rachael M. , Song Geoboo
Published: February 2016

Recently, a controversial policy debate has arisen concerning the installation of high‐voltage power lines in northwest Arkansas. While proponents argue that such an installation is inevitable to efficiently and reliably support the identified electric load in the region, opponents claim that the lines will degrade the natural environment and hamper the tourism‐based local economy in affected regions, notably in Ozark Mountain areas. Of particular interest is to understand how local policy elites perceive the benefits and risks associated with such divisive proposals, which is critical for comprehending the formation and changes of related government policies. Based upon the dual process theory of judgment, this study systematically investigates the triadic relationships between (a) more profound personal value predispositions, (b) affects and feelings, and (c) perceived benefits and risks related to the proposed installation of high‐voltage power lines among local policy elites in the state of Arkansas. In doing so, we analyze original data collected from a statewide Internet survey of 420 local leaders and key policymakers about their opinions on the related issues, while considering other factors claimed by previous literature to influence risk perceptions, including trust, knowledge level, and demographic characteristics. Analytical results suggest that grid‐group cultural predispositions, as deeply held core values within local policy elites’ individual belief systems, both directly and indirectly—through affective feelings—shape perceived utility associated with the installation of high‐voltage power lines. We conclude this article by suggesting some practical considerations for better designing policy addressing controversial issues of this nature.
Lung Cancer Risk from Radon in Marcellus Shale Gas in Northeast U.S. Homes
Authors: Mitchell Austin L. , Griffin W. Michael , Casman Elizabeth A.
Published: February 2016

The amount of radon in natural gas varies with its source. Little has been published about the radon from shale gas to date, making estimates of its impact on radon‐induced lung cancer speculative. We measured radon in natural gas pipelines carrying gas from the Marcellus Shale in Pennsylvania and West Virginia. Radon concentrations ranged from 1,520 to 2,750 Bq/m3(41–74 pCi/L), and the throughput‐weighted average was 1,983 Bq/m3(54 pCi/L). Potential radon exposure due to the use of Marcellus Shale gas for cooking and space heating using vent‐free heaters or gas ranges in northeastern U.S. homes and apartments was assessed. Though the measured radon concentrations are higher than what has been previously reported, it is unlikely that exposure from natural gas cooking would exceed 1.2 Bq/m3(<1% of the U.S. Environmental Protection Agency's action level). Using worst‐case assumptions, we estimate the excess lifetime (70 years) lung cancer risk associated with cooking to be 1.8×10−4(interval spanning 95% of simulation results: 8.5×10−5, 3.4×10−4). The risk profile for supplemental heating with unvented gas appliances is similar. Individuals using unvented gas appliances to provide primary heating may face lifetime risks as high as 3.9×10−3. Under current housing stock and gas consumption assumptions, expected levels of residential radon exposure due to unvented combustion of Marcellus Shale natural gas in the Northeast United States do not result in a detectable change in the lung cancer death rates.
Insights into the Societal Risk of Nuclear Power Plant Accidents
Authors: Denning Richard , Mubayi Vinod
Published: February 2016

The elements of societal risk from a nuclear power plant accident are clearly illustrated by the Fukushima accident: land contamination, long‐term relocation of large numbers of people, loss of productive farm area, loss of industrial production, and significant loss of electric capacity. NUREG‐1150 and other studies have provided compelling evidence that the individual health risk of nuclear power plant accidents is effectively negligible relative to other comparable risks, even for people living in close proximity to a plant. The objective of this study is to compare the societal risk of nuclear power plant accidents to that of other events to which the public is exposed. We have characterized the monetized societal risk in the United States from major societally disruptive events, such as hurricanes, in the form of a complementary cumulative distribution function. These risks are compared with nuclear power plant risks, based on NUREG‐1150 analyses and new MACCS code calculations to account for differences in source terms determined in the more recent SOARCA study. A candidate quantitative societal objective is discussed for potential adoption by the NRC. The results are also interpreted with regard to the acceptability of nuclear power as a major source of future energy supply.
Determining performance characteristics of an NGS‐based HLA typing method for clinical applications
Authors: Duke J. L. , Lind C. , Mackiewicz K. , Ferriola D. , Papazoglou A. , Gasiewski A. , Heron S. , Huynh A. , McLaughlin L. , Rogers M. , Slavich L. , Walker R. , Monos D. S.
Published: February 2016

This study presents performance specifications of an in‐house developed human leukocyte antigen (HLA) typing assay using next‐generation sequencing (NGS) on the Illumina MiSeq platform. A total of 253 samples, previously characterized for HLA‐A, ‐B, ‐C, ‐DRB1 and ‐DQB1 were included in this study, which were typed at high‐resolution using a combination of Sanger sequencing, sequence‐specific primer (SSP) and sequence‐specific oligonucleotide probe (SSOP) technologies and recorded at the two‐field level. Samples were selected with alleles that cover a high percentage of HLA specificities in each of five different race/ethnic groups: European, African‐American, Asian Pacific Islander, Hispanic and Native American. Sequencing data were analyzed by two software programs, Omixon's target and GenDx's NGSengine. A number of metrics including allele balance, sensitivity, specificity, precision, accuracy and remaining ambiguity were assessed. Data analyzed by the two software systems are shown independently. The majority of alleles were identical in the exonic sequences (third field) with both programs for HLA‐A, ‐B, ‐C and ‐DQB1 in 97.7% of allele determinations. Among the remaining discrepant genotype calls at least one of the analysis programs agreed with the reference typing. Upon additional manual analysis 100% of the 2530 alleles were concordant with the reference HLA genotypes; the remaining ambiguities did not exceed 0.8%. The results demonstrate the feasibility and significant benefit of HLA typing by NGS as this technology is highly accurate, eliminates virtually all ambiguities, provides complete sequencing information for the length of the HLA gene and forms the basis for utilizing a single methodology for HLA typing in the immunogenetics labs.
Carbon dioxide‐mediated vasomotion of extra‐cranial cerebral arteries in humans: a role for prostaglandins?
Authors: Hoiland Ryan L. , Tymko Michael M. , Bain Anthony R. , Wildfong Kevin W. , Monteleone Brad , Ainslie Philip N.
Published: February 2016

Key points

Cerebral blood flow increases during hypercapnia and decreases during hypocapnia; it is unknown if vasomotion of the internal carotid artery is implicated in these responses.

Indomethacin, a non‐selective cyclooxygenase inhibitor (used to inhibit prostaglandin synthesis), has a unique ability to blunt cerebrovascular carbon dioxide reactivity, while other cyclooxygenase inhibitors have no effect.

We show significant dilatation and constriction of the internal carotid artery during hypercapnia and hypocapnia, respectively.

Indomethacin, but not ketorolac or naproxen, reduced the dilatatory response of the internal carotid artery to hypercapnia

The differential effect of indomethacin compared to ketorolac and naproxen suggests that indomethacin inhibits vasomotion of the internal carotid artery independent of prostaglandin synthesis inhibition.

Extra‐cranial cerebral blood vessels are implicated in the regulation of cerebral blood flow during changes in arterial CO2; however, the mechanisms governing CO2‐mediated vasomotion of these vessels in humans remain unclear. We determined if cyclooxygenase inhibition with indomethacin (INDO) reduces the vasomotor response of the internal carotid artery (ICA) to changes in end‐tidal CO2 (). Using a randomized single‐blinded placebo‐controlled study, participants (n = 10) were tested on two occasions, before and 90 min following oral INDO (1.2 mg kg–1) or placebo. Concurrent measurements of beat‐by‐beat velocity, diameter and blood flow of the ICA were made at rest and during steady‐state stages (4 min) of iso‐oxic hypercapnia (+3, +6, +9 mmHg ) and hypocapnia (−3, −6, −9 mmHg ). To examine if INDO affects ICA vasomotion independent of cyclooxygenase inhibition, two participant subsets (each n = 5) were tested before and following oral ketorolac (post 45 min, 0.25 mg kg–1) or naproxen (post 90 min, 4.2 mg kg–1). During pre‐drug testing in the INDO trial, the ICA dilatated during hypercapnia at +6 mmHg (4.72 ± 0.45 vs. 4.95 ± 0.51 mm; P < 0.001) and +9 mmHg (4.72 ± 0.45 mm vs. 5.12 ± 0.47 mm; P < 0.001), and constricted during hypocapnia at −6 mmHg (4.95 ± 0.33 vs. 4.88 ± 0.27 mm; P < 0.05) and −9 mmHg (4.95 ± 0.33 vs. 4.82 ± 0.27 mm; P < 0.001). Following INDO, vasomotor responsiveness of the ICA to hypercapnia was reduced by 67 ± 28% (0.045 ± 0.015 vs. 0.015 ± 0.012 mm mmHg −1). There was no effect of the drug in the ketorolac and naproxen trials. We conclude that: (1) INDO markedly reduces the vasomotor response of the ICA to changes in ; and (2) INDO may be reducing CO2‐mediated vasomotion via a mechanism(s) independent of cyclooxygenase inhibition.
Effect of High Freestream Turbulence on Flowfields of Shaped Film Cooling Holes
Authors: Schroeder Robert P. , Thole Karen A.
Published: February 2016

Shaped film cooling holes have become a standard geometry for protecting gas turbine components. Few studies, however, have reported flowfield measurements for moderately expanded shaped holes and even fewer have reported on the effects of high freestream turbulence intensity relevant to gas turbine airfoils. This study presents detailed flowfield and adiabatic effectiveness measurements for a shaped hole at freestream turbulence intensities of 0.5% and 13%. Test conditions included blowing ratios of 1.5 and 3 at a density ratio of 1.5. Measured flowfields revealed a counter-rotating vortex pair (CRVP) and high jet penetration into the mainstream at the blowing ratio of 3. Elevated freestream turbulence had a minimal effect on mean velocities and rather acted by increasing turbulence intensity around the coolant jet, resulting in increased lateral spreading of coolant.
Experimental Investigation on Flows in a Corrugated Channel
Authors: Ünal Efe , Ahn Hojin , Sorguven Esra
Published: February 2016

Flows in a corrugated channel are investigated by a high-speed camera and a particle image velocimetry (PIV) system. The bottom wall of the rectangular channel was corrugated with periodic grooves while the top wall and two sidewalls were flat plates made of Plexiglas. Flow visualization data from the high-speed camera determine the critical Reynolds number to be around 1500 by examining the stability of the vortex in the groove as well as fluid ejection from the groove. The visualization data for turbulent flow also show how a vortex evolves within the groove and triggers another vortex formation in the subsequent groove, and how fluid ejected from the groove triggers another ejection from the subsequent groove. Thus, strong hydrodynamic interactions are observed between successive corrugations. In addition, PIV data provide the profiles of velocities and Reynolds stresses as a function of Reynolds number. Time-averaged streamlines show that a large, stable vortex exists in the groove for laminar flow. On the other hand, for turbulent flow, the vortex is unstable inside the groove, often prompting fluid ejection which interacts with the bulk flow. Especially the Reynolds stress of the square of velocity fluctuation in the direction normal to the bulk flow significantly increases as the fluid ejection from the groove intensifies with increasing Reynolds number.
Interfacial Pressure Coefficient for Ellipsoids and Its Effect on the Two-Fluid Model Eigenvalues
Authors: Vaidheeswaran Avinash , de Bertodano Martin Lopez
Published: February 2016

Analytical expressions for interfacial pressure coefficients are obtained based on the geometry of the bubbles occurring in two-phase flows. It is known that the shape of the bubbles affects the virtual mass and interfacial pressure coefficients, which in turn determines the cutoff void fraction for the well-posedness of two-fluid model (TFM). The coefficient used in the interfacial pressure difference correlation is derived assuming potential flow around a perfect sphere. In reality, the bubbles seen in two-phase flows get deformed, and hence, it is required to estimate the coefficients for nonspherical geometries. Oblate and prolate ellipsoids are considered, and their respective coefficients are determined. It is seen that the well-posedness limit of the TFM is determined by the combination of virtual mass and interfacial pressure coefficient used. The effect of flow separation on the coefficient values is also analyzed.
Protofold II: Enhanced Model and Implementation for Kinetostatic Protein Folding1
Authors: Tavousi Pouya , Behandish Morad , Ilieş Horea T. , Kazerounian Kazem
Published: February 2016

A reliable prediction of three-dimensional (3D) protein structures from sequence data remains a big challenge due to both theoretical and computational difficulties. We have previously shown that our kinetostatic compliance method (KCM) implemented into the Protofold package can overcome some of the key difficulties faced by other de novo structure prediction methods, such as the very small time steps required by the molecular dynamics (MD) approaches or the very large number of samples needed by the Monte Carlo (MC) sampling techniques. In this paper, we improve the free energy formulation used in Protofold by including the typically underrated entropic effects, imparted due to differences in hydrophobicity of the chemical groups, which dominate the folding of most water-soluble proteins. In addition to the model enhancement, we revisit the numerical implementation by redesigning the algorithms and introducing efficient data structures that reduce the expected complexity from quadratic to linear. Moreover, we develop and optimize parallel implementations of the algorithms on both central and graphics processing units (CPU/GPU) achieving speed-ups up to two orders of magnitude on the GPU. Our simulations are consistent with the general behavior observed in the folding process in aqueous solvent, confirming the effectiveness of model improvements. We report on the folding process at multiple levels, namely, the formation of secondary structural elements and tertiary interactions between secondary elements or across larger domains. We also observe significant enhancements in running times that make the folding simulation tractable for large molecules.
Magnetohydrodynamics Mixed Convection in a Lid-Driven Cavity Having a Corrugated Bottom Wall and Filled With a Non-Newtonian Power-Law Fluid Under the Influence of an Inclined Magnetic Field
Authors: Selimefendigil Fatih , Chamkha Ali J.
Published: February 2016

In this study, the problem of magnetohydrodynamics (MHD) mixed convection of lid-driven cavity with a triangular-wave shaped corrugated bottom wall filled with a non-Newtonian power-law fluid is numerically studied. The bottom corrugated wall of the cavity is heated and the top moving wall is kept at a constant lower temperature while the vertical walls of the enclosure are considered to be adiabatic. The governing equations are solved by the Galerkin weighted residual finite element formulation. The influence of the Richardson number (between 0.01 and 100), Hartmann number (between 0 and 50), inclination angle of the magnetic field (between 0 deg and 90 deg), and the power-law index (between 0.6 and 1.4) on the fluid flow and heat transfer characteristics are numerically investigated. It is observed that the effects of free convection are more pronounced for a shear-thinning fluid and the buoyancy force is weaker for the dilatant fluid flow compared to that of the Newtonian fluid. The averaged heat transfer decreases with increasing values of the Richardson number and enhancement is more effective for a shear-thickening fluid. At the highest value of the Hartmann number, the averaged heat transfer is the lowest for a pseudoplastic fluid. As the inclination angle of the magnetic field increases, the averaged Nusselt number generally enhances.
Numerical Solution of Time-Fractional Klein–Gordon Equation by Using the Decomposition Methods
Authors: Jafari Hossein
Published: February 2016

In this paper, we apply two decomposition methods, the Adomian decomposition method (ADM) and a well-established iterative method, to solve time-fractional Klein–Gordon type equation. We compare these methods and discuss the convergence of them. The obtained results reveal that these methods are very accurate and effective.
Modeling on Microdroplet Formation for Cell Printing Based on Alternating Viscous-Inertial Force Jetting
Authors: Zhao Long , Yan Karen Chang , Yao Rui , Lin Feng , Sun Wei
Published: February 2016

Drop-on-demand (DOD) microdroplet jetting technology has diverse applications ranging from additive manufacturing (AM) and the integrated circuit (IC) industry to cell printing. An engineering model of droplet formation can provide insights for optimizing the process and ensuring its controllability and reproducibility. This paper reports a development of an engineering model on the fluid outflow and microdroplet formation based on alternating viscous-inertial force jetting (AVIFJ). The model provides a fundamental understanding on the mechanism of droplet formation driven by the alternating viscous force and inetial force. Furthermore, the model studies the fluid acceleration, velocity, and displacement under the conditions of a uniform cylindrical nozzle and a nonuniform cylindrical nozzle. In conjunction with an energy-based criterion for droplet formation, the model is applied to predict the formability of single microdroplets and the volume and velocity of formed microdroplets. A series of experiments was conducted to validate the developed model. The results show that the model predictions agree well with the experimental results. Specifically, comparing the model prediction and experimental results, the maximum difference of drop diameter is 4 μm, and the maximum difference of drop velocity is 0.3 m/s. These results suggest that the developed theoretical model will provide guidance to the subsequent cell printing applications.
Effects of Process Parameters on White Layer Formation and Morphology in Hard Turning of AISI52100 Steel
Authors: Zhang Xiao-Ming , Chen Li , Ding Han
Published: February 2016

Hard turning is becoming increasingly considered by industry as a potential substitute for grinding. However, it is greatly hurdled by surface integrity problems such as tensile residual stress and white layer, which are generally found to have negative effects on the stress corrosion, wear resistance, and fatigue life of the machined parts. This paper investigates white layer formation and morphology in hard turning process using various process parameters, taking into account the effects of heat treatment which results in microstructure and hardness differences on bulk materials. Samples undergone three typical heat treatment processes are prepared and then machined using different cutting speeds and radial feed rates. Optical microscope, scanning electron microscope (SEM), and X-ray diffraction (XRD) are employed to analyze the microstructures of white layer and bulk materials after varies heat treatments and cutting processes. Through the studies, we find the existence of a cutting speed threshold, below which no white layer forms for both the low and medium-temperature tempering. The threshold value increases; however, the white layer thickness decreases under the same cutting conditions, for the low and medium-temperature tempering, respectively. Also, we find that the white layer thickness and the scattering of it along the cutting direction on the surface increases with cutting speed and radial feed rate. White layer with wavy morphology can be found in samples after quenching at high cutting speed. We first discover that the pitch of the white layer with wavy morphology is similar to the displacement of tool at the time a segment of the serrated chips forms. Also, the surface residual stresses of the samples are measured. Relationship between white layer and residual stresses is presented. Based on the relationship we reveal that high temperature is more dominant than volume expansion for white layer formation.
Performance of a Composite Repair System for Externally Corroded Metallic Pipe Using Numerical Model
Authors: Arif Abul Fazal M. , Anis M. , Al-Omari A.
Published: February 2016

Traditionally, corroded pipelines with metal loss defects have been repaired by replacing the defective areas with metallic pipe segments or by welding on metallic sleeves. Considering the technical and economic advantages of composite materials, literature shows that these defects can be repaired or reinforced with a composite sleeve system. In these systems, epoxy filler is used to fill the corrosion defect followed by wrapping the piping segment with concentric coils of composite material. However several challenges need to be met to obtain the desired repair quality. The major considerations are surface preparation, reduction in operating pressure for the repair, the duration required (e.g. for curing of the composite material) for the composite repair to share the load from the pipe, and the most important is the in-field quality assessment and to ensure consistency between several repairs. In this work, a numerical model is developed to investigate the performance of composite repair systems and compare with the traditional metallic welded sleeve. The effect of fiber orientation, repair sleeve thickness, material and installation pressure have been studied. Results show the potential of composite repair system in replacing the existing welded metallic non-pressure containing sleeve for metallic pipelines.
Mesh Selection for Progressive Failure Modeling of Carbon Fiber Panels in Mode III Shear Using an Explicit Finite Element Solver
Authors: Daniels Mitchell A. , Hyder Imran , Suryan Levi J. , Parmigiani John P.
Published: February 2016

Modeling progressive failure of composite materials can be a challenging task. It is further complicated by mesh dependency of finite element solvers when implementing the Hashin criterion. As one continues to refine the mesh, the finite element analysis (FEA) continues to yield varying solutions; hence there is no converged solution for continuous mesh refinement. This is due to mesh dependency when modeling strain softening. The FEA package Abaqus attempts to mitigate this but the issue is not eliminated.

Methods that address mesh dependency include experimental validation and numerical analysis. Experimental validation tailors the mesh to match a specific result. This mesh would then be applicable to other configurations with the same geometry and loading; however, experimental validation with increasingly complex parts for FEA is costly and time consuming. Numerical approaches to mesh selection do not require experimental validation; however, these methods may be computationally expensive depending on the analysis. A mesh selection strategy that does not require experimental validation, while computationally efficient, should be implemented for design purposes.

This study investigates a mesh selection strategy based on a converged elastic solution; the coarsest mesh that converges to a solution in the linear-elastic portion of the material response is chosen for analysis. Previous studies using an implicit solver yielded good results for out-of-plane loading conditions; however this procedure has not been implemented for explicit solvers. In this study, an investigation was conducted to determine the appropriate mesh to model progressive damage for notched, carbon fiber composite panels in out-of-plane shear (mode III) using an explicit solver in Abaqus/Explicit. This study analyzed 20 ply thick panels and considered three stacking sequences: 10%, 30%, and 50% zero degree plies. The procedure initially disabled damage and identified the coarsest mesh that approached a converged elastic solution. Using this mesh, damage was enabled and the models were run with loading proceeding through damage initiation until failure. The panels’ material response were extracted from the finite element (FE) model and filtered in order to determine their maximum load-carrying ability. The FE predicted maximum loads were then compared to corresponding experimental data in order to validate the mesh selection procedure. This process is not limited to out-of-plane shear; the potential for this mesh selection method would allow for progressive failure simulation to be more applicable in the design process of composite structures instead of post-damage analysis.
Three-Dimensional Compliant Cellular Materials: A Mechanism Based Material Design
Authors: Kim Kwangwon , Ju Jaehyung , Kim Doo-Man
Published: February 2016

Cellular materials have two important properties: structures and mechanisms. These properties have important applications in materials design; in particular, they’re used to determine the modulus and yield strain. The objective of this study is to gain a better understanding of these two properties and to explore the synthesis of three-dimensional (3D) compliant cellular materials (CCMs) with compliant porous structures (CPSes) generated from modified hexagonal honeycombs. An orthotropic constitutive CCM model in the Cartesian coordinate system is constructed using the strain energy method, which uses the deformation of hinges around holes and the rotation of links. A finite element (FE) based simulation is conducted to validate the analytical model. The moduli and yield strains of the 3D CCMs with an aluminum alloy are about 1.2GPa and 0.4% in the longitudinal direction and about 0.08MPa and 30% in the lateral direction. The CCMs have extremely high positive and negative Poisson’s ratios νxy*∼±30 due to the large rotation of the link member in the transverse direction caused by an input displacement in the longitudinal direction. This paper demonstrates that compliant me so structures can be used for next generation materials design in tailoring mechanical properties such as moduli, strength, strain, and Poisson’s ratios.