bluuebunny/crossref_metadata_2025 huggingface dataset:
A review of snow in Britain
Authors: Kay Alison L.
Published: June 2016

Climate change is likely to have a significant effect on snow globally, with most effect where current winter temperatures are close to 0°C, including parts of upland Britain. There is evidence of decreasing trends in observations of snowfall and lying snow in Britain, and climate projections suggest a continuation of this trend. Although river flows in Britain are generally dominated by rainfall rather than snowmelt, some upland catchments have a significant snowmelt contribution. There is evidence of changes in observed and projected river flows in some catchments in Britain, linked to changes in snow, but it can be difficult to distinguish the effects of snow changes from those of other concurrent changes (climatic and non-climatic). Flow regime changes in catchments with widespread and prolonged winter snow cover usually involve increases in winter flow and decreases in spring flow, but the effect on catchments with more transient snow cover is less clear, as is the effect on high flows and water quality. Snow can also affect a number of other factors of socio-economic or environmental importance (e.g. transport and farming). There is some evidence that disruption due to snow may be less frequent in the future, but disruption from other types of weather events may increase. The impacts of snow tend to be worse in areas where events occur less frequently, due to unpreparedness, so there is a need to guard against complacency when it comes to future snow events in Britain, which can still be expected despite a likely reduction in frequency. Further modelling of the potential impacts of climate change, including modelling the influence of snow changes as well as other climatic and non-climatic changes, would aid adaptation and encourage mitigation.
Vegetation structure influences the retention of airfall tephra in a sub-Arctic landscape
Authors: Cutler Nick A. , Bailey Richard M. , Hickson Katherine T. , Streeter Richard T. , Dugmore Andrew J.
Published: June 2016

Vegetation cover mediates a number of important geomorphological processes. However, the effect of different vegetation types on the retention of fine aeolian sediment is poorly understood. We investigated this phenomenon, using the retention of fine, pyroclastic material (tephra) from the 2011 eruption of the Grímsvötn volcano, Iceland, as a case study. We set out to quantify structural variation in different vegetation types and to relate structural metrics to the thickness of recently deposited volcanic ash layers in the sedimentary section. We utilised a combination of vegetation and soil surveys, along with photogrammetric analysis of vegetation structure. We found that indices of plant community composition were a poor proxy for vegetation structure and were largely unrelated to tephra thickness. However, structural metrics, derived from photogrammetric analysis, were clearly related to variations in tephra layer thickness at a landscape scale and tephra layers under shrub patches were significantly thicker than those outside the shrub canopy. We therefore concluded that: a) vegetation cover was a critical factor in the retention of fine aeolian sediment for deposit depths up to few centimetres; b) structural variation in vegetation cover played a major role in determining the configuration of tephra deposits in the sedimentary section. These findings have implications for the analysis of ancient volcanic eruptions and archaeological/palaeoenvironmental reconstructions based on the interpretation of tephra deposits. Furthermore, they present the possibility that the detailed form of tephra layers may be used as a proxy for palaeo vegetation structure.
Determination of the bond–slip behavior of CFRP-to-steel bonded interfaces using digital image correlation
Authors: Wang Hai-Tao , Wu Gang , Dai Yun-Tong , He Xiao-Yuan
Published: June 2016

The bond–slip behavior between carbon fiber reinforced polymer (CFRP) plates and steel is crucial for predicting the structural behavior of CFRP-strengthened steel members. In this paper, the CFRP-to-steel bonded joints with different bond lengths and adhesive thicknesses were tested to investigate the bond–slip behavior of CFRP-to-steel bonded interfaces. The digital image correlation (DIC) technique was used to measure the displacement and strain data. The test results, including the failure mode, ultimate load, displacement distribution, and CFRP strain distribution, are presented and discussed. The non-linear bond–slip curves of CFRP-to-steel bonded interfaces are determined by a fitting procedure for CFRP strain distributions. A bilinear bond–slip relationship is further proposed to simplify the non-linear bond–slip curve. The test results indicate that the adhesive thickness has an influence on the failure mode, ultimate load, and bond–slip behavior. Similar to a CFRP-to-concrete bonded interface, an effective bond length also exists for a CFRP-to-steel bonded interface. The development of the interfacial shear stress is analyzed based on the determined non-linear and bilinear bond–slip curves. Finally, two theoretical models are employed for the prediction of the ultimate load, effective bond length and bond–slip curve. This study shows that the DIC method is suitable for investigating the bond–slip behavior of CFRP-to-steel bonded joints.
Effect of ply level thickness uncertainty on reliability of laminated composite panels
Authors: Zhang Shufeng , Zhang Li , Wang Yashun , Tao Junyong , Chen Xun
Published: June 2016

The present study provides a comparative investigation and discussion on the influence of laminate thickness uncertainty on reliability of laminated composite. Laminate thickness uncertainty in three different scenarios is considered: component level thickness uncertainty, fiber-dominated ply level thickness uncertainty and matrix-dominated ply level thickness uncertainty. Monte-Carlo and Markov-chain Monte-Carlo methods are employed to calculate failure probabilities of symmetric and balanced laminate panels bearing uniaxial and multiaxial loads. It is shown that conventional considerations on laminate thickness uncertainty in the component level could underestimate or overestimate the composite failure probability. Ply level thickness uncertainty primarily caused by fiber or matrix quantity may also result in very different failure probabilities. This study highlights the importance of a thorough analysis and classification of the laminate thickness uncertainty in the ply level in order to achieve confident reliability evaluation of composite structures.
Disparity Between Fusion Center Web Content and Self-Reported Activity
Authors: Carter Jeremy G. , Lewandowski Carla , May Gabrielle A.
Published: June 2016

The fusion center literature is limited and lacks consensus regarding operational focus and strategic priorities. Perhaps the lone consistent finding in this literature is the lack of awareness among outsiders regarding what fusion centers do and the capabilities they provide. Contemporary communication research indicates the Internet serves as the primary source of information to inform what they do not understand. The present study employs a mixed methods approach that combines a content analysis of fusion center web content with fusion center self-report data gleaned from a federally funded project. This study encompasses 74 of the 77 primary and officially recognized fusion centers in the United States. Results indicate that centers provide limited information online about their organization and significantly underreport their activities and capabilities online in comparison to self-reported tasks. Information available online through official fusion centers websites is poor at best. Fusion centers self-report to engage in tasks consistent with their information sharing and analytic mission. A context for the findings is provided in addition to recommendations and study limitations.
Recommendations for Replication Research in Special Education
Authors: Coyne Michael D. , Cook Bryan G. , Therrien William J.
Published: June 2016

Special education researchers conduct studies that can be considered replications. However, they do not often refer to them as replication studies. The purpose of this article is to consider the potential benefits of conceptualizing special education intervention research within a framework of systematic, conceptual replication. Specifically, we advocate for the value and importance of replication research that includes both closely aligned and distal conceptual replications. We acknowledge the challenges associated with conducting replications in applied school-based research and also provide recommendations for how to design, conduct, and report replication studies in special education research with the goal of supporting the identification of effective practices for individuals with disabilities.
Optimization design of the valve spring for abnormal noise control in a single-cylinder gasoline engine
Authors: Zheng Hao , Yan Fuwu , Lu Chihua , Xu Fengxiang , Li Qiuyue , Tian Wei
Published: June 2016

To address the abnormal noise problem of single-cylinder gasoline engines in the idle condition, acoustic spectral and intensity analysis was carried out. Then the noises were identified as valve impact noises caused by the anomalous dynamic performance of the engine valve mechanism. To improve further the dynamic performance of the mechanism by optimization of the valve spring, a multi-body dynamic model of the valve mechanism was developed on the basis of the key performance and the structure parameters of the valve spring. By using the optimization strategy, the oscillation amplitude of the valve spring and the valve impact force can be reduced by about 62.5% and 27% respectively. Finally, optimized sample pieces were produced for acoustic verification tests. The obtained results showed that the engine’s overall working noise was reduced by about 2.0 dB(A), and the sound quality of the engine was determined using both objective measurements and subjective evaluation of the noise, vibration and harshness performance. It can be concluded that the valve impact noise can be reduced by optimization of the valve springs.
A 600-year-long stratigraphic record of tsunamis in south-central Chile
Authors: Hong Isabel , Dura Tina , Ely Lisa L , Horton Benjamin P , Nelson Alan R , Cisternas Marco , Nikitina Daria , Wesson Robert L
Published: June 2016

The stratigraphy within coastal river valleys in south-central Chile clarifies and extends the region’s history of large, earthquakes and accompanying tsunamis. Our site at Quidico (38.1°S, 73.3°W) is located in an overlap zone between ruptures of magnitude 8–9 earthquakes in 1960 and 2010, and, therefore, records tsunamis originating from subduction-zone ruptures north and south of the city of Concepción. Hand-dug pits and cores in a 3-m-thick sequence of freshwater peat in an abandoned meander (a little-examined depositional environment for tsunami deposits) and exposures along the Quidico River show five sand beds that extend as much as 1.2 km inland. Evidence for deposition of the beds by tsunamis includes tabular sand beds that are laterally extensive (>100 m), well sorted, fine upward, have sharp lower contacts, and contain diatom assemblages dominated by brackish and marine taxa. Using eyewitness accounts of tsunami inundation, 137Cs analyses, and 14C dating, we matched the upper four sand beds with historical tsunamis in 2010, 1960, 1835, and 1751. The oldest prehistoric bed dates to 1445–1490 CE and correlates with lacustrine and coastal records of similar-aged earthquakes and tsunamis in south-central Chile.
Historicizing Hypertext and Web 2.0: Access, Governmentality and Cyborgs
Authors: Balakrishnan Sreepriya
Published: June 2016

This article attempts to analyze the relation between individual, the machinic systems and capitalist ideology that gets more consolidated with the digital by looking closely at the ways in which the human–machine relation gets standardized through the ‘stabilization’ of technology in what is referred to as Web 2.0. Considering certain aspects of print culture that led to what Foucault refers to as the ‘principles of exclusion’—the way in which discourses delimit itself—the larger cultural economies that involved the production and manipulation of symbols in web is critically re-examined. The print-informed relation of individual and text finds its contemporary ramifications in our understanding and usage of hypertext as HTML. The article traces the crucial stages during the establishment of World Wide Web at the turn of the century and affects the question ‘What is a blogger’ in the same vein that the question ‘What is an Author’ was asked to trace the role that weblog format played in the constitution of ‘access’ to cyberspace. The larger implication of such an enquiry would be to situate ‘cyborg’ subjectivity as one that consolidates human identities as more textual, archived and accessible. The amalgamation of human–machine capacities through the stabilization of material technologies in the digital world concern the governmentality of bodies through HTML, its ideological significations and the praxis that led to its stabilization in the turn of the millennium.
Antiarrhythmic Drug Therapy for Rhythm Control in Atrial Fibrillation
Authors: Waks Jonathan W. , Zimetbaum Peter
Published: June 2016

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and affects over 33 million people worldwide. AF is associated with stroke and systemic thromboembolism, unpleasant symptoms and reduced quality of life, heart failure, and increased mortality, and treatment of AF and its complications are associated with significant cost. Antiarrhythmic drugs (AADs) can suppress AF, allowing long-term maintenance of sinus rhythm, and have the potential to relieve symptoms and reverse or prevent adverse effects associated with AF. However, large randomized controlled studies evaluating use of AADs have not demonstrated a clear benefit to maintaining sinus rhythm, and AADs often have significant limitations, including a modest rate of overall success at maintaining sinus rhythm, frequent side effects, and potentially life-threatening toxicities. Although some of the currently available AADs have been available for almost 100 years, better tolerated and more efficacious AADs have recently been developed both for long-term maintenance of sinus rhythm and for chemical cardioversion of AF to sinus rhythm. Advances in automated AF detection with cardiac implantable electronic devices have suggested that AADs might be useful for suppressing AF to allow safe discontinuation of anticoagulation in select patients who are in sinus rhythm for prolonged periods of time. AADs may also have synergistic effects with catheter ablation of AF. This review summarizes the pharmacology and clinical use of currently available AADs for treatment of AF and discusses novel AADs and future directions for rhythm control in AF.
Economic evaluation of 5-HT3 receptor antagonists in combination with dexamethasone for the prevention of ‘overall’ nausea and vomiting following highly emetogenic chemotherapy in Chinese adult patients
Authors: Du Qiong , Zhai Qing , Zhu Bin , Xu Xiao-Le , Yu Bo
Published: June 2016

Background

Two pivotal Phase III trials compared the efficacy of palonosetron, ondansetron and granisetron, combined with dexamethasone, for the prevention of nausea and vomiting following highly emetogenic chemotherapy. However, an economic evaluation of these three regimens in the real-world setting of Chinese adult patients has not been determined.

Objectives

To estimate, from the perspective of the Chinese healthcare system, which of these frequently used strategies consisting of 0.25 mg palonosetron (0.25P), 16 mg ondansetron (Onda), and 3 mg granisetron (Gran), is the most cost-effective option in patients following highly emetogenic chemotherapy.

Methods

A Markov decision-analytic model was developed. The health and economic outcomes of the three strategies; 0.25P, Onda, and Gran were investigated. The clinical and utility data were taken from published studies. The cost data were calculated according to current local Chinese practices. Sensitivity analyses were performed to determine the impact of uncertainty regarding the results.

Results

The base-case analysis showed that the 0.25P strategy yielded maximum health benefits compared with the other two strategies. However, the probabilistic sensitivity analysis demonstrated that the Gran strategy was the most cost-effective approach when the willingness-to-pay threshold was not more than US$22,515/quality-adjusted life year. Moreover, palonosetron is not cost-effective in preventing ‘overall’ nausea and vomiting following highly emetogenic chemotherapy in Chinese patients.

Conclusions

Our analysis suggests that, compared with palonosetron and ondansetron, 3 mg granisetron may be a cost-effective treatment option in the current Chinese healthcare setting.
Conceptualizing an Ethology of Masculinities
Authors: McDonald Terrance H.
Published: June 2016

Rather than a definition or redefinition of masculinity, or masculinities, this article asks what can masculinities do? To explore this question, I map the possibilities that Deleuze and Guattari’s philosophy of immanence offer masculinities theory. Through a theoretical encounter with Deleuze, Guattari, Spinoza, and Gatens, I seek to open up an alternative conceptualization of masculinities that moves away from morality—transcendent judgments of good or bad—and toward an ethics that privileges our capacities for affecting and being affected. While masculinities studies and gender theory has proposed related notions concerning gender fluidity and resisting gender binaries, this article proposes an alternative through Deleuze’s and Gatens’ readings of Spinoza’s Ethics that radically challenges the mind–body split that informs traditional lineages of Western philosophy. What is at stake for this essay is the ability to conceive of masculinities as creative force with no allegiance to the male body other than its capacity to affect or be affected.
Epilepsy in multiple sclerosis: The role of temporal lobe damage
Authors: Calabrese M , Castellaro M , Bertoldo A , De Luca A , Pizzini FB , Ricciardi GK , Pitteri M , Zimatore S , Magliozzi R , Benedetti MD , Manganotti P , Montemezzi S , Reynolds R , Gajofatto A , Monaco S
Published: June 2016

Background:

Although temporal lobe pathology may explain some of the symptoms of multiple sclerosis (MS), its role in the pathogenesis of seizures has not been clarified yet.

Objectives:

To investigate the role of temporal lobe damage in MS patients suffering from epilepsy, by the application of advanced multimodal 3T magnetic resonance imaging (MRI) analysis.

Methods:

A total of 23 relapsing remitting MS patients who had epileptic seizures (RRMS/E) and 23 disease duration matched RRMS patients without any history of seizures were enrolled. Each patient underwent advanced 3T MRI protocol specifically conceived to evaluate grey matter (GM) damage. This includes grey matter lesions (GMLs) identification, evaluation of regional cortical thickness and indices derived from the Neurite Orientation Dispersion and Density Imaging model.

Results:

Regional analysis revealed that in RRMS/E, the regions most affected by GMLs were the hippocampus (14.2%), the lateral temporal lobe (13.5%), the cingulate (10.0%) and the insula (8.4%). Cortical thinning and alteration of diffusion metrics were observed in several regions of temporal lobe, in insular cortex and in cingulate gyrus of RRMS/E compared to RRMS ( p< 0.05 for all comparisons).

Conclusions:

Compared to RRMS, RRMS/E showed more severe damage of temporal lobe, which exceeds what would be expected on the basis of the global GM damage observed.
Realist complex intervention science: Applying realist principles across all phases of the Medical Research Council framework for developing and evaluating complex interventions
Authors: Fletcher Adam , Jamal Farah , Moore Graham , Evans Rhiannon E. , Murphy Simon , Bonell Chris
Published: June 2016

The integration of realist evaluation principles within randomised controlled trials (‘realist RCTs’) enables evaluations of complex interventions to answer questions about what works, for whom and under what circumstances. This allows evaluators to better develop and refine mid-level programme theories. However, this is only one phase in the process of developing and evaluating complex interventions. We describe and exemplify how social scientists can integrate realist principles across all phases of the Medical Research Council framework. Intervention development, modelling, and feasibility and pilot studies need to theorise the contextual conditions necessary for intervention mechanisms to be activated. Where interventions are scaled up and translated into routine practice, realist principles also have much to offer in facilitating knowledge about longer-term sustainability, benefits and harms. Integrating a realist approach across all phases of complex intervention science is vital for considering the feasibility and likely effects of interventions for different localities and population subgroups.
Realist evaluation and randomised controlled trials for testing program theory in complex social systems
Authors: Hawkins Andrew J.
Published: June 2016

Scientific evaluation seeks to develop and test theories that describe and explain the value of interventions into the world. Realist approaches to scientific evaluation tend to be strong on theory and explanation, but lack adequate tests or means of validating theory. The focus of this article is the potential for randomisation and experimentation to provide evidence for transfactual (i.e. reusable or portable) context–mechanism–outcome configurations (CMOs) in complex adaptive systems. The article is not concerned with attribution of outcomes to past programs but for developing scientific knowledge that can be used for future interventions. It seeks to elucidate the warrant that underpins the randomised controlled trial (RCT) and why it is useful in some fields of science but less so in complex social systems. Realist RCTs are considered but rejected; instead a form of propensity score matching is proposed for testing realist program theory, estimating the effect size of a purported CMO, and generating scientific knowledge for developing more effective interventions into complex social systems.
Reimbursements for telehealth services are likely to be lower than non-telehealth services in the United States
Authors: Wilson Fernando A , Rampa Sankeerth , Trout Kate E , Stimpson Jim P
Published: June 2016

Telehealth technologies promise to increase access to care, particularly in underserved communities. However, little is known about how private payer reimbursements vary between telehealth and non-telehealth services. We use the largest private claims database in the United States provided by the Health Care Cost Institute to identify telehealth claims and compare average reimbursements to non-telehealth claims. We find average reimbursements for telehealth services are significantly lower than those for non-telehealth for seven of the ten most common services. For example, telehealth reimbursements for office visits for evaluation and management of established patients with low complexity were 30% lower than the corresponding non-telehealth service. Reimbursements by clinical diagnosis code also tended to be lower for telehealth than non-telehealth claims. Widespread adoption of telehealth may be hampered by lower reimbursements for telehealth services relative to face-to-face services. This may result in lower incentives for providers to invest in telehealth technologies that do not result in significant cost savings to their practice, even if telehealth improves patient outcomes.
Professional socialization and commitment to the profession in social work students: A longitudinal study exploring the effect of attitudes, perception of the profession, teaching, training, and supervision
Authors: Freund Anat , Cohen Ayala , Blit-Cohen Edith , Dehan Nicole
Published: June 2016

The article attempts to characterize social work students in higher education institutes in Israel, regarding professional socialization and the development of commitment to the profession during their BA (undergraduate) studies, lasting three years. This longitudinal study included a sample of 450 students in four social work schools. Data was gathered throughout four time periods: during the first two weeks of the academic year and at the end of each academic year.

Findings

Students, during the first academic year, harbor certain misconceptions about the profession, leading to a sharp decrease in their commitment to the profession. However, it seems that supervisors, teachers and decisionmakers in social work schools somehow manage to bring the fantasies entertained by students at the beginning of their studies into line with reality, leading to both higher and stronger commitment to the profession by the time they complete their BA degree.

Applications

The article discusses the findings and their implications on the social work profession, in general, and on social work training, in particular, regarding the development of commitment to the profession over the years.
Dimensions of Women’s Mate Preferences
Authors: Atari Mohammad , Jamali Ramin
Published: June 2016

A large number of studies have assessed human mate preferences using lists of characteristics. To date, there is little data regarding mate preferences in Iran. The present study aimed to investigate dimensions in mate preferences among Iranian women and to validate a female-specific instrument in Iranian context. Three studies were designed and conducted. The first study was an interview-based qualitative analysis of women’s mate preferences. The second study provided a psychometrically sound list of 26 characteristics in a potential mate. The third study confirmed the five-factor structure of the instrument. In sum, five dimensions of mate preferences among Iranian women are kindness/dependability, status/resources, attractiveness/sexuality, religiosity/chastity, and education/intelligence, as measured by the newly developed 26-item scale.
Bourdieu on supply: Utilizing the ‘theory of practice’ to understand complexity and culpability in heroin and crack cocaine user-dealing
Authors: Moyle Leah , Coomber Ross
Published: June 2016

The act of user-dealing has largely been explored within criminology in conjunction with the ‘drug–crime’ link or with a focus on ethnography and subculture. Whereas it is known that many users of drugs such as heroin and crack cocaine engage in small-scale supply as a way of generating revenue, less is known about the particular interplay of social context and choice that leads them to pick this income-generating activity over other potential options. Contributing to a burgeoning literature, this article explores the constrained choices of user-dealers with reference to Bourdieu’s ‘theory of practice’ (1977). Through locating stories of failure in user-dealer narratives, we utilize this novel approach in criminology, illuminating the importance of working with all of the interrelated concepts of habitus, field and capital in appreciating user-dealing as ‘practice’. It is argued that application of this framework affords the previously unharnessed opportunity to use Bourdieusian theory to understand notions of culpability when sentencing this group.
Comprehensive and Holistic Analysis of HT-29 Colorectal Cancer Cells and Tumor-Bearing Nude Mouse Model: Interactions Among Fractions Derived From the Chinese Medicine Formula Tian Xian Liquid in Effects on Human Colorectal Carcinoma
Authors: Leigh Annballaw Bridget , Cheung Ho Pan , Lin Li-zhu , Ng Tzi Bun , Lao Lixing , Zhang Yanbo , Zhang Zhang-Jin , Tong Yao , Sze Stephen Cho Wing
Published: June 2016

The Chinese medicine formula Tian Xian Liquid (TXL) has been used clinically for cancer therapy in China for more than 25 years. However, the comprehensive and holistic effects of its bioactive fractions for various antitumor therapeutic effects have not been unraveled. This is the first study to scientifically elucidate the holistic effect of Chinese medicine formula for treating colon cancer, hence allowing a better understanding of the essence of Chinese medicine formula, through the comparison of the actions of TXL and its functional constituent fractions, including ethyl acetate (EA), butanol (BU), and aqueous (WA) fractions. Tissue-specific proliferative/antiproliferative effects of these fractions on human colorectal carcinoma HT-29 cells and splenocytes were studied by using the MTT assay. Their modulations on the expression of markers of antiproliferation, antimetastasis, reversion of multidrug resistance in treated HT-29 cells were examined with real-time polymerase chain reaction and Western blot analysis, and their modulations in a xenografted nude mouse model were examined by Western blot analysis. Results revealed that EA fraction slightly inhibited the proliferation of HT-29 cells, but tissue-specifically exerted the most potent antiproliferative effect on splenocytes. On the contrary, only TXL and BU fraction tissue-specifically contributed to the proliferation of splenocytes, but inhibited the proliferation of HT-29 cells. WA fraction exerted the most potent antiproliferative effect on HT-29 cells and also the strongest inhibitory action on tumor size in the nude mouse model in our previous study. In the HT-29 model, TXL and WA fraction exerted the most pronounced effect on upregulation of p21 mRNA and protein; TXL, and EA and WA fractions exerted the effect on downregulation of G1 phase cell cycle protein, cyclin D1 mRNA and protein; EA and BU fractions exerted the most prominent anti-invasive effect on anti-invasion via downregulation of MMP-1 mRNA; TXL potently reversed most multidrug resistance via downregulation of MDR-1 protein. In conclusion, the comprehensive and holistic effects of TXL were demonstrated with ( a) mutual accentuation and mutual enhancement, ( b) mutual counteraction and mutual suppression, and ( c) mutual antagonism among the 3 constituent fractions. Moreover, the design of the present study may lead to further development of more tissue-specific effective drugs with minimal side effects for clinical use in combating carcinoma.
Simultaneous Endovascular Treatment of Tandem Internal Carotid Lesions
Authors: Cvetic Vladimir , Dragas Marko , Colic Momcilo , Vukasinovic Ivan , Radmili Oliver , Ilic Nikola , Koncar Igor , Bascarevic Vladimir , Ristanovic Natasa , Davidovic Lazar
Published: June 2016

The incidence of concomitant extracranial carotid artery stenosis and ipsilateral intracranial carotid aneurysm has been reported to vary between 2.8% and 5%. These complex lesions may present a challenge for treatment decision-making. This case report describes an asymptomatic male patient with severe carotid bifurcation stenosis, coupled with an unruptured supraclinoid internal carotid aneurysm. Both lesions were treated simultaneously. Patient underwent carotid stenting followed by aneurysm coiling in the same setting without any complication.
Validated analytical modeling of diesel engine regulated exhaust CO emission rate
Authors: Faris Waleed F , Rakha Hesham A , Elmoselhy Salah
Published: June 2016

Albeit vehicle analytical models are often favorable for explainable mathematical trends, no analytical model has been developed of the regulated diesel exhaust CO emission rate for trucks yet. This research unprecedentedly develops and validates for trucks a model of the steady speed regulated diesel exhaust CO emission rate analytically. It has been found that the steady speed–based CO exhaust emission rate is based on (1) CO2 dissociation, (2) the water–gas shift reaction, and (3) the incomplete combustion of hydrocarbon. It has been found as well that the steady speed–based CO exhaust emission rate based on CO2 dissociation is considerably less than the rate that is based on the water–gas shift reaction. It has also been found that the steady speed–based CO exhaust emission rate based on the water–gas shift reaction is the dominant source of CO exhaust emission. The study shows that the average percentage of deviation of the steady speed–based simulated results from the corresponding field data is 1.7% for all freeway cycles with 99% coefficient of determination at the confidence level of 95%. This deviation of the simulated results from field data outperforms its counterpart of widely recognized models such as the comprehensive modal emissions model and VT-Micro for all freeway cycles.
Measurements of the laminar burning velocity for propane: Air mixtures
Authors: Ebaid Munzer SY , Al-Khishali Kutiaba JM
Published: June 2016

In this research, an experimental setup was built based on using K-type thermocouples inserted in a cylindrical vessel and coupled with a computer system to enable online reading of flame speed for propane-air mixtures. The work undertaken here has come up with data for laminar burning velocity of the propane-air mixtures based on three initial temperatures Tu = 300, 325 and 350 K, three initial pressures pu = 0.5, 1.0 and 1.5 bar over a range of equivalence ratios ϕ between 0.6 and 1.5. The results obtained gave a reasonable agreement with experimental data reported in the literature. Results showed that laminar burning velocity increases at low initial pressures and decreases at high pressures, while the opposite occurs incase of temperatures. The maximum values of the laminar burning velocity occur at T = 350 K, pu = 0.5 and ϕ = 1.0, respectively, while the minimum values of the laminar burning velocity occur at T = 300 K, pu = 1.5 and ϕ = 1.2. Also, the influence of flame stretching on laminar burning velocity was investigated and it was found that stretch effect is weak since Lewis number was below unity for all cases considered. Based on experimental results, an empirical equation has been derived to calculate the laminar burning velocity. The values of the laminar burning velocity calculated from this equation show great compatibility with the published results. Therefore, the derived empirical equation can be used to calculate the burning velocities of any gas of paraffin gas fuels in the range of mixture temperature and pressure considered.
Retina image–based optic disc segmentation
Authors: Wang Ching-Lin , Hsieh Ming-Yuan , Hung Yi-Wen , Tsai Meng-Hsiun , Chan Mao-Hsiang , Chen Jui-Ming , Tung Kwong-Chung
Published: June 2016

The change of optic disc can be used to diagnose many eye diseases, such as glaucoma, diabetic retinopathy and macular degeneration. Moreover, retinal blood vessel pattern is unique for human beings even for identical twins. It is a highly stable pattern in biometric identification. Since optic disc is the beginning of the optic nerve and main blood vessels in retina, it can be used as a reference point of identification. Therefore, optic disc segmentation is an important technique for developing a human identity recognition system and eye disease diagnostic system. This article hence presents an optic disc segmentation method to extract the optic disc from a retina image. The experimental results show that the optic disc segmentation method can give impressive results in segmenting the optic disc from a retina image.
Numerical investigation of flow around a pipeline with a spoiler near a rigid bed
Authors: Öner Ahmet Alper
Published: June 2016

Interaction of current with circular cylinders near a rigid bed is significant in the design of offshore structures, such as pipelines. Pipelines are buried to the seabed to be protected from damages caused by hydrodynamic forces or human activities. The pipeline laid on movable bed can be buried due to local scouring. A vertical plate on pipeline, called spoiler, has been developed to increase the rate and extend of scouring. In this study, the two-dimensional turbulent flow around a smooth pipeline with a spoiler was investigated at Re D = 9500 near the bed. The governing equations for the current problem were solved using ANSYS® 11.0-Flotran program package based on finite element method. The performance of the standard k–ε, standard k–ω, and shear stress transport turbulence models were examined on five computational meshes with different densities. The results obtained were compared with the published experimental measurements in literature. Present results showed that the attachment of a spoiler caused a large separation area in both upstream and downstream of the pipeline. The attachment of spoiler on top of the pipe increased the drag and decreased the lift force on pipe. Moreover, the spoiler causes non-zero downward lift. It is concluded that the k–ω turbulence model on the finest mesh is found relatively better in simulation of the flow field.
Multi-condition optimization and experimental study of impeller blades in a mixed-flow pump
Authors: Liu Houlin , Chen Xinxiang , Wang Kai , Tan Minggao , Zhou Xiaohua
Published: June 2016

On the basis of design of experiment and numerical simulation, a reliable optimization method for blades of a mixed-flow pump is proposed with the maximum weighted average efficiency at multi-conditions as optimum objective. First, the performance of the model pump was measured and the test results were used to validate the simulation method. To improve the simulation accuracy, the check of the grid independence and the comparison of different turbulence models were done in detail. Then, the method of design of experiment for key geometrical parameters was used to obtain the optimization scheme. The maximum weighted average efficiency of pump at three operation conditions was chosen as optimum objective. The optimum solution was gotten and confirmed by the experiment. The results demonstrate that efficiency of the mixed-flow pump with optimized impeller increases by 3.9%, and the high-efficiency zone is increased from 0.021 to 0.040.
Microstructure evolution in AZ61 alloy processed by equal channel angular pressing
Authors: Avvari Muralidhar , S Narendranath , Able Mashamba
Published: June 2016

Magnesium and its alloys are finding increasing use in aerospace, automobile, nuclear, electrical, and structural engineering applications because of their high strength-to-weight ratio when compared to aluminum, titanium, and steel. In this work, AZ61 wrought magnesium alloy was processed using equal channel angular pressing at three different temperatures of 483, 523, and 573 K using up to four equal channel angular pressing passes. A microstructural study was conducted by measuring the average grain size after each pass, for the three different processing temperatures. The mechanical properties of the processed samples were noted to improve due to the reduction in the grain size after each equal channel angular pressing pass. After four equal channel angular pressing passes, the average grain size of the AZ61 samples was found to be reduced to 85%, 81%, and 70% for the pressing temperatures of 483, 523, and 573 K, respectively. The tensile strength of the AZ61 alloy increased with increase in the number of equal channel angular pressing passes for each of the temperatures when compared to as-received alloy. For instance, for the processing temperatures of 483, 523, and 573 K, the tensile strength increased by 24%, 10%, and 12%, respectively, at four equal channel angular pressing passes. Also, the percentage elongation of the alloy was increased with increase in processing temperatures. Moreover, fracture topographies of the tensile surfaces are illustrated through scanning electron microcopy and reveal ductile fracture than as-received alloy for four passes at each equal channel angular pressing processing temperature.
Failure analysis and structure optimization of the connecting thread of driving shaft in positive displacement motor
Authors: Zhu Xiaohua , Lin Dian , Li Jianan
Published: June 2016

Due to high efficiency in helping breaking rocks, positive displacement motor has a widespread application in the field of oil and gas drilling engineering. However, service life of positive displacement motor becomes shorter resulting from failure of the driving shaft thread. The three-dimensional simulation model of driving shaft’s connecting thread has been developed based on the principle of virtual work, Von Mises yield criterion, and contact nonlinear theory. This article has put forward the plan to optimize structure of driving shaft with straight thread based on the design principle of double-shouldered thread; besides, fatigue life of driving shaft with straight thread before and after optimization has been assessed by resorting to the multiaxial fatigue principle and Brown–Miller critical plane rule. In line with research results, mechanical properties of driving shaft with straight thread are superior to those of driving shaft with taper thread. Under the load of axial drill pressure with fluctuation and alternating torque, fatigue life of driving shaft with straight thread after optimization is greatly improved. This article has not only provided basis for optimizing connecting thread of driving shaft but also boasts of high engineering value for improving service life of positive displacement motor.
Assessment of finite element and smoothed particles hydrodynamics methods for modeling serrated chip formation in hardened steel
Authors: Umer Usama , Mohammed Muneer Khan , Qudeiri Jaber Abu , Al-Ahmari Abdulrahman
Published: June 2016

This study aims to perform comparative analyses in modeling serrated chip morphologies using traditional finite element and smoothed particles hydrodynamics methods. Although finite element models are being employed in predicting machining performance variables for the last two decades, many drawbacks and limitations exist with the current finite element models. The problems like excessive mesh distortions, high numerical cost of adaptive meshing techniques, and need of geometric chip separation criteria hinder its practical implementation in metal cutting industries. In this study, a mesh free method, namely, smoothed particles hydrodynamics, is implemented for modeling serrated chip morphology while machining AISI H13 hardened tool steel. The smoothed particles hydrodynamics models are compared with the traditional finite element models, and it has been found that the smoothed particles hydrodynamics models have good capabilities in handling large distortions and do not need any geometric or mesh-based chip separation criterion.
Pressure fluctuation prediction in pump mode using large eddy simulation and unsteady Reynolds-averaged Navier–Stokes in a pump–turbine
Authors: Li De-You , Han Lei , Wang Hong-Jie , Gong Ru-Zhi , Wei Xian-Zhu , Qin Da-Qing
Published: June 2016

For pump–turbines, most of the instabilities couple with high-level pressure fluctuations, which are harmful to pump–turbines, even the whole units. In order to understand the causes of pressure fluctuations and reduce their amplitudes, proper numerical methods should be chosen to obtain the accurate results. The method of large eddy simulation with wall-adapting local eddy-viscosity model was chosen to predict the pressure fluctuations in pump mode of a pump–turbine compared with the method of unsteady Reynolds-averaged Navier–Stokes with two-equation turbulence model shear stress transport k–ω. Partial load operating point (0.91 QBEP) under 15-mm guide vane opening was selected to make a comparison of performance and frequency characteristics between large eddy simulation and unsteady Reynolds-averaged Navier–Stokes based on the experimental validation. Good agreement indicates that the method of large eddy simulation could be applied in the simulation of pump–turbines. Then, a detailed comparison of variation for peak-to-peak value in the whole passage was presented. Both the methods show that the highest level pressure fluctuations occur in the vaneless space. In addition, the propagation of amplitudes of blade pass frequency, 2 times of blade pass frequency, and 3 times of blade pass frequency in the circumferential and flow directions was investigated. Although the difference exists between large eddy simulation and unsteady Reynolds-averaged Navier–Stokes, the trend of variation in different parts is almost the same. Based on the analysis, using the same mesh (8 million), large eddy simulation underestimates pressure characteristics and shows a better result compared with the experiments, while unsteady Reynolds-averaged Navier–Stokes overestimates them.
Prevalence and commonalities of informed consent templates for biomedical research
Authors: Jackson Jhia LN , Larson Elaine
Published: June 2016

Improving the informed consent process is a common theme in literature regarding biomedical human subjects research. Standards for appropriate language and required information have undergone scrutiny and evolved over time. One response to the call for improvement is the provision and use of informed consent templates (ICTs) to ensure that documents have a standardized format and quality of content. Little is known, however, about the prevalence of such ICTs or their effectiveness. This article discusses the rationale for creating and using templates, describes the prevalence of and commonalities between templates, and identifies the need for an evaluation of their effectiveness in terms of their ethical and practical implications. The websites of 144 Association of American Medical Colleges (AAMC)-accredited institutions in the United States, 21 institutes in the National Institutes of Health (NIH), and the World Health Organization (WHO) were searched for the presence of ICTs. A total of 105 (72.9%) medical schools, 3 (14.2%) NIH institutes, and the WHO had at least one ICT publicly available on their websites. The templates varied in format, length, style, language, and sections included. The prevalence of ICTs, variability in their content, and lack of published research regarding their effectiveness suggest that ICTs are available, but more research into their effectiveness and standardization of their development are needed.
Eletriptan in the management of acute migraine: an update on the evidence for efficacy, safety, and consistent response
Authors: Capi Matilde , Curto Martina , Lionetto Luana , de Andrés Fernando , Gentile Giovanna , Negro Andrea , Martelletti Paolo
Published: June 2016

Migraine is a multifactorial, neurological and disabling disorder, also characterized by several autonomic symptoms. Triptans, selective serotonin 5-HT1B/1D agonists, are the first-line treatment option for moderate-to-severe headache attacks. In this paper, we review the recent data on eletriptan clinical efficacy, safety, and tolerability, and potential clinically relevant interactions with other drugs. Among triptans, eletriptan shows a consistent and significant clinical efficacy and a good tolerability profile in the treatment of migraine, especially for patients with cardiovascular risk factors without coronary artery disease. It shows the most favorable clinical response, together with sumatriptan injections, zolmitriptan and rizatriptan. Additionally, eletriptan shows the most complex pharmacokinetic/dynamic profile compared with the other triptans. It is metabolized primarily by the CYP3A4 hepatic enzyme and therefore the concomitant administration of CYP3A4-potent inhibitors should be carefully evaluated. A relatively low risk of serotonin syndrome is given by the co-administration with serotoninergic drugs. No clinically relevant interaction has been found with drugs used for migraine prophylactic treatment or other acute drugs, with the exception of ergot derivatives that should not be co-administered with eletriptan.